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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- E X P _ C H 9 --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2021, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
-- for more details. You should have received a copy of the GNU General --
-- Public License distributed with GNAT; see file COPYING3. If not, go to --
-- http://www.gnu.org/licenses for a complete copy of the license. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
with Atree; use Atree;
with Aspects; use Aspects;
with Checks; use Checks;
with Einfo; use Einfo;
with Einfo.Entities; use Einfo.Entities;
with Einfo.Utils; use Einfo.Utils;
with Elists; use Elists;
with Errout; use Errout;
with Exp_Ch3; use Exp_Ch3;
with Exp_Ch6; use Exp_Ch6;
with Exp_Ch11; use Exp_Ch11;
with Exp_Dbug; use Exp_Dbug;
with Exp_Sel; use Exp_Sel;
with Exp_Smem; use Exp_Smem;
with Exp_Tss; use Exp_Tss;
with Exp_Util; use Exp_Util;
with Freeze; use Freeze;
with Hostparm;
with Itypes; use Itypes;
with Namet; use Namet;
with Nlists; use Nlists;
with Nmake; use Nmake;
with Opt; use Opt;
with Restrict; use Restrict;
with Rident; use Rident;
with Rtsfind; use Rtsfind;
with Sem; use Sem;
with Sem_Aux; use Sem_Aux;
with Sem_Ch5; use Sem_Ch5;
with Sem_Ch6; use Sem_Ch6;
with Sem_Ch8; use Sem_Ch8;
with Sem_Ch9; use Sem_Ch9;
with Sem_Ch11; use Sem_Ch11;
with Sem_Ch13; use Sem_Ch13;
with Sem_Elab; use Sem_Elab;
with Sem_Eval; use Sem_Eval;
with Sem_Res; use Sem_Res;
with Sem_Util; use Sem_Util;
with Sinfo; use Sinfo;
with Sinfo.Nodes; use Sinfo.Nodes;
with Sinfo.Utils; use Sinfo.Utils;
with Snames; use Snames;
with Stand; use Stand;
with Targparm; use Targparm;
with Tbuild; use Tbuild;
with Uintp; use Uintp;
with Validsw; use Validsw;
package body Exp_Ch9 is
-- The following constant establishes the upper bound for the index of
-- an entry family. It is used to limit the allocated size of protected
-- types with defaulted discriminant of an integer type, when the bound
-- of some entry family depends on a discriminant. The limitation to entry
-- families of 128K should be reasonable in all cases, and is a documented
-- implementation restriction.
Entry_Family_Bound : constant Pos := 2**16;
-----------------------
-- Local Subprograms --
-----------------------
function Actual_Index_Expression
(Sloc : Source_Ptr;
Ent : Entity_Id;
Index : Node_Id;
Tsk : Entity_Id) return Node_Id;
-- Compute the index position for an entry call. Tsk is the target task. If
-- the bounds of some entry family depend on discriminants, the expression
-- computed by this function uses the discriminants of the target task.
procedure Add_Object_Pointer
(Loc : Source_Ptr;
Conc_Typ : Entity_Id;
Decls : List_Id);
-- Prepend an object pointer declaration to the declaration list Decls.
-- This object pointer is initialized to a type conversion of the System.
-- Address pointer passed to entry barrier functions and entry body
-- procedures.
procedure Add_Formal_Renamings
(Spec : Node_Id;
Decls : List_Id;
Ent : Entity_Id;
Loc : Source_Ptr);
-- Create renaming declarations for the formals, inside the procedure that
-- implements an entry body. The renamings make the original names of the
-- formals accessible to gdb, and serve no other purpose.
-- Spec is the specification of the procedure being built.
-- Decls is the list of declarations to be enhanced.
-- Ent is the entity for the original entry body.
function Build_Accept_Body (Astat : Node_Id) return Node_Id;
-- Transform accept statement into a block with added exception handler.
-- Used both for simple accept statements and for accept alternatives in
-- select statements. Astat is the accept statement.
function Build_Barrier_Function
(N : Node_Id;
Ent : Entity_Id;
Pid : Entity_Id) return Node_Id;
-- Build the function body returning the value of the barrier expression
-- for the specified entry body.
function Build_Barrier_Function_Specification
(Loc : Source_Ptr;
Def_Id : Entity_Id) return Node_Id;
-- Build a specification for a function implementing the protected entry
-- barrier of the specified entry body.
procedure Build_Contract_Wrapper (E : Entity_Id; Decl : Node_Id);
-- Build the body of a wrapper procedure for an entry or entry family that
-- has contract cases, preconditions, or postconditions. The body gathers
-- the executable contract items and expands them in the usual way, and
-- performs the entry call itself. This way preconditions are evaluated
-- before the call is queued. E is the entry in question, and Decl is the
-- enclosing synchronized type declaration at whose freeze point the
-- generated body is analyzed.
function Build_Corresponding_Record
(N : Node_Id;
Ctyp : Entity_Id;
Loc : Source_Ptr) return Node_Id;
-- Common to tasks and protected types. Copy discriminant specifications,
-- build record declaration. N is the type declaration, Ctyp is the
-- concurrent entity (task type or protected type).
function Build_Dispatching_Tag_Check
(K : Entity_Id;
N : Node_Id) return Node_Id;
-- Utility to create the tree to check whether the dispatching call in
-- a timed entry call, a conditional entry call, or an asynchronous
-- transfer of control is a call to a primitive of a non-synchronized type.
-- K is the temporary that holds the tagged kind of the target object, and
-- N is the enclosing construct.
function Build_Entry_Count_Expression
(Concurrent_Type : Node_Id;
Component_List : List_Id;
Loc : Source_Ptr) return Node_Id;
-- Compute number of entries for concurrent object. This is a count of
-- simple entries, followed by an expression that computes the length
-- of the range of each entry family. A single array with that size is
-- allocated for each concurrent object of the type.
function Build_Find_Body_Index (Typ : Entity_Id) return Node_Id;
-- Build the function that translates the entry index in the call
-- (which depends on the size of entry families) into an index into the
-- Entry_Bodies_Array, to determine the body and barrier function used
-- in a protected entry call. A pointer to this function appears in every
-- protected object.
function Build_Find_Body_Index_Spec (Typ : Entity_Id) return Node_Id;
-- Build subprogram declaration for previous one
function Build_Lock_Free_Protected_Subprogram_Body
(N : Node_Id;
Prot_Typ : Node_Id;
Unprot_Spec : Node_Id) return Node_Id;
-- N denotes a subprogram body of protected type Prot_Typ. Unprot_Spec is
-- the subprogram specification of the unprotected version of N. Transform
-- N such that it invokes the unprotected version of the body.
function Build_Lock_Free_Unprotected_Subprogram_Body
(N : Node_Id;
Prot_Typ : Node_Id) return Node_Id;
-- N denotes a subprogram body of protected type Prot_Typ. Build a version
-- of N where the original statements of N are synchronized through atomic
-- actions such as compare and exchange. Prior to invoking this routine, it
-- has been established that N can be implemented in a lock-free fashion.
function Build_Parameter_Block
(Loc : Source_Ptr;
Actuals : List_Id;
Formals : List_Id;
Decls : List_Id) return Entity_Id;
-- Generate an access type for each actual parameter in the list Actuals.
-- Create an encapsulating record that contains all the actuals and return
-- its type. Generate:
-- type Ann1 is access all <actual1-type>
-- ...
-- type AnnN is access all <actualN-type>
-- type Pnn is record
-- <formal1> : Ann1;
-- ...
-- <formalN> : AnnN;
-- end record;
function Build_Protected_Entry
(N : Node_Id;
Ent : Entity_Id;
Pid : Node_Id) return Node_Id;
-- Build the procedure implementing the statement sequence of the specified
-- entry body.
function Build_Protected_Entry_Specification
(Loc : Source_Ptr;
Def_Id : Entity_Id;
Ent_Id : Entity_Id) return Node_Id;
-- Build a specification for the procedure implementing the statements of
-- the specified entry body. Add attributes associating it with the entry
-- defining identifier Ent_Id.
function Build_Protected_Spec
(N : Node_Id;
Obj_Type : Entity_Id;
Ident : Entity_Id;
Unprotected : Boolean := False) return List_Id;
-- Utility shared by Build_Protected_Sub_Spec and Expand_Access_Protected_
-- Subprogram_Type. Builds signature of protected subprogram, adding the
-- formal that corresponds to the object itself. For an access to protected
-- subprogram, there is no object type to specify, so the parameter has
-- type Address and mode In. An indirect call through such a pointer will
-- convert the address to a reference to the actual object. The object is
-- a limited record and therefore a by_reference type.
function Build_Protected_Subprogram_Body
(N : Node_Id;
Pid : Node_Id;
N_Op_Spec : Node_Id) return Node_Id;
-- This function is used to construct the protected version of a protected
-- subprogram. Its statement sequence first defers abort, then locks the
-- associated protected object, and then enters a block that contains a
-- call to the unprotected version of the subprogram (for details, see
-- Build_Unprotected_Subprogram_Body). This block statement requires a
-- cleanup handler that unlocks the object in all cases. For details,
-- see Exp_Ch7.Expand_Cleanup_Actions.
function Build_Renamed_Formal_Declaration
(New_F : Entity_Id;
Formal : Entity_Id;
Comp : Entity_Id;
Renamed_Formal : Node_Id) return Node_Id;
-- Create a renaming declaration for a formal, within a protected entry
-- body or an accept body. The renamed object is a component of the
-- parameter block that is a parameter in the entry call.
--
-- In Ada 2012, if the formal is an incomplete tagged type, the renaming
-- does not dereference the corresponding component to prevent an illegal
-- use of the incomplete type (AI05-0151).
function Build_Selected_Name
(Prefix : Entity_Id;
Selector : Entity_Id;
Append_Char : Character := ' ') return Name_Id;
-- Build a name in the form of Prefix__Selector, with an optional character
-- appended. This is used for internal subprograms generated for operations
-- of protected types, including barrier functions. For the subprograms
-- generated for entry bodies and entry barriers, the generated name
-- includes a sequence number that makes names unique in the presence of
-- entry overloading. This is necessary because entry body procedures and
-- barrier functions all have the same signature.
procedure Build_Simple_Entry_Call
(N : Node_Id;
Concval : Node_Id;
Ename : Node_Id;
Index : Node_Id);
-- Build the call corresponding to the task entry call. N is the task entry
-- call, Concval is the concurrent object, Ename is the entry name and
-- Index is the entry family index.
-- Note that N might be expanded into an N_Block_Statement if it gets
-- inlined.
function Build_Task_Proc_Specification (T : Entity_Id) return Node_Id;
-- This routine constructs a specification for the procedure that we will
-- build for the task body for task type T. The spec has the form:
--
-- procedure tnameB (_Task : access tnameV);
--
-- where name is the character name taken from the task type entity that
-- is passed as the argument to the procedure, and tnameV is the task
-- value type that is associated with the task type.
function Build_Unprotected_Subprogram_Body
(N : Node_Id;
Pid : Node_Id) return Node_Id;
-- This routine constructs the unprotected version of a protected
-- subprogram body, which contains all of the code in the original,
-- unexpanded body. This is the version of the protected subprogram that is
-- called from all protected operations on the same object, including the
-- protected version of the same subprogram.
procedure Build_Wrapper_Bodies
(Loc : Source_Ptr;
Typ : Entity_Id;
N : Node_Id);
-- Ada 2005 (AI-345): Typ is either a concurrent type or the corresponding
-- record of a concurrent type. N is the insertion node where all bodies
-- will be placed. This routine builds the bodies of the subprograms which
-- serve as an indirection mechanism to overriding primitives of concurrent
-- types, entries and protected procedures. Any new body is analyzed.
procedure Build_Wrapper_Specs
(Loc : Source_Ptr;
Typ : Entity_Id;
N : in out Node_Id);
-- Ada 2005 (AI-345): Typ is either a concurrent type or the corresponding
-- record of a concurrent type. N is the insertion node where all specs
-- will be placed. This routine builds the specs of the subprograms which
-- serve as an indirection mechanism to overriding primitives of concurrent
-- types, entries and protected procedures. Any new spec is analyzed.
procedure Collect_Entry_Families
(Loc : Source_Ptr;
Cdecls : List_Id;
Current_Node : in out Node_Id;
Conctyp : Entity_Id);
-- For each entry family in a concurrent type, create an anonymous array
-- type of the right size, and add a component to the corresponding_record.
function Concurrent_Object
(Spec_Id : Entity_Id;
Conc_Typ : Entity_Id) return Entity_Id;
-- Given a subprogram entity Spec_Id and concurrent type Conc_Typ, return
-- the entity associated with the concurrent object in the Protected_Body_
-- Subprogram or the Task_Body_Procedure of Spec_Id. The returned entity
-- denotes formal parameter _O, _object or _task.
function Copy_Result_Type (Res : Node_Id) return Node_Id;
-- Copy the result type of a function specification, when building the
-- internal operation corresponding to a protected function, or when
-- expanding an access to protected function. If the result is an anonymous
-- access to subprogram itself, we need to create a new signature with the
-- same parameter names and the same resolved types, but with new entities
-- for the formals.
function Create_Secondary_Stack_For_Task (T : Node_Id) return Boolean;
-- Return whether a secondary stack for the task T should be created by the
-- expander. The secondary stack for a task will be created by the expander
-- if the size of the stack has been specified by the Secondary_Stack_Size
-- representation aspect and either the No_Implicit_Heap_Allocations or
-- No_Implicit_Task_Allocations restrictions are in effect and the
-- No_Secondary_Stack restriction is not.
procedure Debug_Private_Data_Declarations (Decls : List_Id);
-- Decls is a list which may contain the declarations created by Install_
-- Private_Data_Declarations. All generated entities are marked as needing
-- debug info and debug nodes are manually generation where necessary. This
-- step of the expansion must to be done after private data has been moved
-- to its final resting scope to ensure proper visibility of debug objects.
procedure Ensure_Statement_Present (Loc : Source_Ptr; Alt : Node_Id);
-- If control flow optimizations are suppressed, and Alt is an accept,
-- delay, or entry call alternative with no trailing statements, insert
-- a null trailing statement with the given Loc (which is the sloc of
-- the accept, delay, or entry call statement). There might not be any
-- generated code for the accept, delay, or entry call itself (the effect
-- of these statements is part of the general processing done for the
-- enclosing selective accept, timed entry call, or asynchronous select),
-- and the null statement is there to carry the sloc of that statement to
-- the back-end for trace-based coverage analysis purposes.
procedure Extract_Dispatching_Call
(N : Node_Id;
Call_Ent : out Entity_Id;
Object : out Entity_Id;
Actuals : out List_Id;
Formals : out List_Id);
-- Given a dispatching call, extract the entity of the name of the call,
-- its actual dispatching object, its actual parameters and the formal
-- parameters of the overridden interface-level version. If the type of
-- the dispatching object is an access type then an explicit dereference
-- is returned in Object.
procedure Extract_Entry
(N : Node_Id;
Concval : out Node_Id;
Ename : out Node_Id;
Index : out Node_Id);
-- Given an entry call, returns the associated concurrent object, the entry
-- name, and the entry family index.
function Family_Offset
(Loc : Source_Ptr;
Hi : Node_Id;
Lo : Node_Id;
Ttyp : Entity_Id;
Cap : Boolean) return Node_Id;
-- Compute (Hi - Lo) for two entry family indexes. Hi is the index in an
-- accept statement, or the upper bound in the discrete subtype of an entry
-- declaration. Lo is the corresponding lower bound. Ttyp is the concurrent
-- type of the entry. If Cap is true, the result is capped according to
-- Entry_Family_Bound.
function Family_Size
(Loc : Source_Ptr;
Hi : Node_Id;
Lo : Node_Id;
Ttyp : Entity_Id;
Cap : Boolean) return Node_Id;
-- Compute (Hi - Lo) + 1 Max 0, to determine the number of entries in a
-- family, and handle properly the superflat case. This is equivalent to
-- the use of 'Length on the index type, but must use Family_Offset to
-- handle properly the case of bounds that depend on discriminants. If
-- Cap is true, the result is capped according to Entry_Family_Bound.
procedure Find_Enclosing_Context
(N : Node_Id;
Context : out Node_Id;
Context_Id : out Entity_Id;
Context_Decls : out List_Id);
-- Subsidiary routine to procedures Build_Activation_Chain_Entity and
-- Build_Master_Entity. Given an arbitrary node in the tree, find the
-- nearest enclosing body, block, package, or return statement and return
-- its constituents. Context is the enclosing construct, Context_Id is
-- the scope of Context_Id and Context_Decls is the declarative list of
-- Context.
function Index_Object (Spec_Id : Entity_Id) return Entity_Id;
-- Given a subprogram identifier, return the entity which is associated
-- with the protection entry index in the Protected_Body_Subprogram or
-- the Task_Body_Procedure of Spec_Id. The returned entity denotes formal
-- parameter _E.
function Is_Potentially_Large_Family
(Base_Index : Entity_Id;
Conctyp : Entity_Id;
Lo : Node_Id;
Hi : Node_Id) return Boolean;
-- Determine whether an entry family is potentially large because one of
-- its bounds denotes a discrminant.
function Is_Private_Primitive_Subprogram (Id : Entity_Id) return Boolean;
-- Determine whether Id is a function or a procedure and is marked as a
-- private primitive.
function Null_Statements (Stats : List_Id) return Boolean;
-- Used to check DO-END sequence. Checks for equivalent of DO NULL; END.
-- Allows labels, and pragma Warnings/Unreferenced in the sequence as well
-- to still count as null. Returns True for a null sequence. The argument
-- is the list of statements from the DO-END sequence.
function Parameter_Block_Pack
(Loc : Source_Ptr;
Blk_Typ : Entity_Id;
Actuals : List_Id;
Formals : List_Id;
Decls : List_Id;
Stmts : List_Id) return Entity_Id;
-- Set the components of the generated parameter block with the values
-- of the actual parameters. Generate aliased temporaries to capture the
-- values for types that are passed by copy. Otherwise generate a reference
-- to the actual's value. Return the address of the aggregate block.
-- Generate:
-- Jnn1 : alias <formal-type1>;
-- Jnn1 := <actual1>;
-- ...
-- P : Blk_Typ := (
-- Jnn1'unchecked_access;
-- <actual2>'reference;
-- ...);
function Parameter_Block_Unpack
(Loc : Source_Ptr;
P : Entity_Id;
Actuals : List_Id;
Formals : List_Id) return List_Id;
-- Retrieve the values of the components from the parameter block and
-- assign then to the original actual parameters. Generate:
-- <actual1> := P.<formal1>;
-- ...
-- <actualN> := P.<formalN>;
procedure Reset_Scopes_To (Bod : Node_Id; E : Entity_Id);
-- Reset the scope of declarations and blocks at the top level of Bod to
-- be E. Bod is either a block or a subprogram body. Used after expanding
-- various kinds of entry bodies into their corresponding constructs. This
-- is needed during unnesting to determine whether a body generated for an
-- entry or an accept alternative includes uplevel references.
function Trivial_Accept_OK return Boolean;
-- If there is no DO-END block for an accept, or if the DO-END block has
-- only null statements, then it is possible to do the Rendezvous with much
-- less overhead using the Accept_Trivial routine in the run-time library.
-- However, this is not always a valid optimization. Whether it is valid or
-- not depends on the Task_Dispatching_Policy. The issue is whether a full
-- rescheduling action is required or not. In FIFO_Within_Priorities, such
-- a rescheduling is required, so this optimization is not allowed. This
-- function returns True if the optimization is permitted.
-----------------------------
-- Actual_Index_Expression --
-----------------------------
function Actual_Index_Expression
(Sloc : Source_Ptr;
Ent : Entity_Id;
Index : Node_Id;
Tsk : Entity_Id) return Node_Id
is
Ttyp : constant Entity_Id := Etype (Tsk);
Expr : Node_Id;
Num : Node_Id;
Lo : Node_Id;
Hi : Node_Id;
Prev : Entity_Id;
S : Node_Id;
function Actual_Family_Offset (Hi, Lo : Node_Id) return Node_Id;
-- Compute difference between bounds of entry family
--------------------------
-- Actual_Family_Offset --
--------------------------
function Actual_Family_Offset (Hi, Lo : Node_Id) return Node_Id is
function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id;
-- Replace a reference to a discriminant with a selected component
-- denoting the discriminant of the target task.
-----------------------------
-- Actual_Discriminant_Ref --
-----------------------------
function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id is
Typ : constant Entity_Id := Etype (Bound);
B : Node_Id;
begin
if not Is_Entity_Name (Bound)
or else Ekind (Entity (Bound)) /= E_Discriminant
then
if Nkind (Bound) = N_Attribute_Reference then
return Bound;
else
B := New_Copy_Tree (Bound);
end if;
else
B :=
Make_Selected_Component (Sloc,
Prefix => New_Copy_Tree (Tsk),
Selector_Name => New_Occurrence_Of (Entity (Bound), Sloc));
Analyze_And_Resolve (B, Typ);
end if;
return
Make_Attribute_Reference (Sloc,
Attribute_Name => Name_Pos,
Prefix => New_Occurrence_Of (Etype (Bound), Sloc),
Expressions => New_List (B));
end Actual_Discriminant_Ref;
-- Start of processing for Actual_Family_Offset
begin
return
Make_Op_Subtract (Sloc,
Left_Opnd => Actual_Discriminant_Ref (Hi),
Right_Opnd => Actual_Discriminant_Ref (Lo));
end Actual_Family_Offset;
-- Start of processing for Actual_Index_Expression
begin
-- The queues of entries and entry families appear in textual order in
-- the associated record. The entry index is computed as the sum of the
-- number of queues for all entries that precede the designated one, to
-- which is added the index expression, if this expression denotes a
-- member of a family.
-- The following is a place holder for the count of simple entries
Num := Make_Integer_Literal (Sloc, 1);
-- We construct an expression which is a series of addition operations.
-- See comments in Entry_Index_Expression, which is identical in
-- structure.
if Present (Index) then
S := Entry_Index_Type (Ent);
-- First make sure the index is in range if requested. The index type
-- has been directly set on the prefix, see Resolve_Entry.
if Do_Range_Check (Index) then
Generate_Range_Check
(Index, Etype (Prefix (Parent (Index))), CE_Range_Check_Failed);
end if;
Expr :=
Make_Op_Add (Sloc,
Left_Opnd => Num,
Right_Opnd =>
Actual_Family_Offset (
Make_Attribute_Reference (Sloc,
Attribute_Name => Name_Pos,
Prefix => New_Occurrence_Of (Base_Type (S), Sloc),
Expressions => New_List (Relocate_Node (Index))),
Type_Low_Bound (S)));
else
Expr := Num;
end if;
-- Now add lengths of preceding entries and entry families
Prev := First_Entity (Ttyp);
while Chars (Prev) /= Chars (Ent)
or else (Ekind (Prev) /= Ekind (Ent))
or else not Sem_Ch6.Type_Conformant (Ent, Prev)
loop
if Ekind (Prev) = E_Entry then
Set_Intval (Num, Intval (Num) + 1);
elsif Ekind (Prev) = E_Entry_Family then
S := Entry_Index_Type (Prev);
-- The need for the following full view retrieval stems from this
-- complex case of nested generics and tasking:
-- generic
-- type Formal_Index is range <>;
-- ...
-- package Outer is
-- type Index is private;
-- generic
-- ...
-- package Inner is
-- procedure P;
-- end Inner;
-- private
-- type Index is new Formal_Index range 1 .. 10;
-- end Outer;
-- package body Outer is
-- task type T is
-- entry Fam (Index); -- (2)
-- entry E;
-- end T;
-- package body Inner is -- (3)
-- procedure P is
-- begin
-- T.E; -- (1)
-- end P;
-- end Inner;
-- ...
-- We are currently building the index expression for the entry
-- call "T.E" (1). Part of the expansion must mention the range
-- of the discrete type "Index" (2) of entry family "Fam".
-- However only the private view of type "Index" is available to
-- the inner generic (3) because there was no prior mention of
-- the type inside "Inner". This visibility requirement is
-- implicit and cannot be detected during the construction of
-- the generic trees and needs special handling.
if In_Instance_Body
and then Is_Private_Type (S)
and then Present (Full_View (S))
then
S := Full_View (S);
end if;
Lo := Type_Low_Bound (S);
Hi := Type_High_Bound (S);
Expr :=
Make_Op_Add (Sloc,
Left_Opnd => Expr,
Right_Opnd =>
Make_Op_Add (Sloc,
Left_Opnd => Actual_Family_Offset (Hi, Lo),
Right_Opnd => Make_Integer_Literal (Sloc, 1)));
-- Other components are anonymous types to be ignored
else
null;
end if;
Next_Entity (Prev);
end loop;
return Expr;
end Actual_Index_Expression;
--------------------------
-- Add_Formal_Renamings --
--------------------------
procedure Add_Formal_Renamings
(Spec : Node_Id;
Decls : List_Id;
Ent : Entity_Id;
Loc : Source_Ptr)
is
Ptr : constant Entity_Id :=
Defining_Identifier
(Next (First (Parameter_Specifications (Spec))));
-- The name of the formal that holds the address of the parameter block
-- for the call.
Comp : Entity_Id;
Decl : Node_Id;
Formal : Entity_Id;
New_F : Entity_Id;
Renamed_Formal : Node_Id;
begin
Formal := First_Formal (Ent);
while Present (Formal) loop
Comp := Entry_Component (Formal);
New_F :=
Make_Defining_Identifier (Sloc (Formal),
Chars => Chars (Formal));
Set_Etype (New_F, Etype (Formal));
Set_Scope (New_F, Ent);
-- Now we set debug info needed on New_F even though it does not come
-- from source, so that the debugger will get the right information
-- for these generated names.
Set_Debug_Info_Needed (New_F);
if Ekind (Formal) = E_In_Parameter then
Mutate_Ekind (New_F, E_Constant);
else
Mutate_Ekind (New_F, E_Variable);
Set_Extra_Constrained (New_F, Extra_Constrained (Formal));
end if;
Set_Actual_Subtype (New_F, Actual_Subtype (Formal));
Renamed_Formal :=
Make_Selected_Component (Loc,
Prefix =>
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (Entry_Parameters_Type (Ent),
Make_Identifier (Loc, Chars (Ptr)))),
Selector_Name => New_Occurrence_Of (Comp, Loc));
Decl :=
Build_Renamed_Formal_Declaration
(New_F, Formal, Comp, Renamed_Formal);
Append (Decl, Decls);
Set_Renamed_Object (Formal, New_F);
Next_Formal (Formal);
end loop;
end Add_Formal_Renamings;
------------------------
-- Add_Object_Pointer --
------------------------
procedure Add_Object_Pointer
(Loc : Source_Ptr;
Conc_Typ : Entity_Id;
Decls : List_Id)
is
Rec_Typ : constant Entity_Id := Corresponding_Record_Type (Conc_Typ);
Decl : Node_Id;
Obj_Ptr : Node_Id;
begin
-- Create the renaming declaration for the Protection object of a
-- protected type. _Object is used by Complete_Entry_Body.
-- ??? An attempt to make this a renaming was unsuccessful.
-- Build the entity for the access type
Obj_Ptr :=
Make_Defining_Identifier (Loc,
New_External_Name (Chars (Rec_Typ), 'P'));
-- Generate:
-- _object : poVP := poVP!O;
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Make_Defining_Identifier (Loc, Name_uObject),
Object_Definition => New_Occurrence_Of (Obj_Ptr, Loc),
Expression =>
Unchecked_Convert_To (Obj_Ptr, Make_Identifier (Loc, Name_uO)));
Set_Debug_Info_Needed (Defining_Identifier (Decl));
Prepend_To (Decls, Decl);
-- Generate:
-- type poVP is access poV;
Decl :=
Make_Full_Type_Declaration (Loc,
Defining_Identifier =>
Obj_Ptr,
Type_Definition =>
Make_Access_To_Object_Definition (Loc,
Subtype_Indication =>
New_Occurrence_Of (Rec_Typ, Loc)));
Set_Debug_Info_Needed (Defining_Identifier (Decl));
Prepend_To (Decls, Decl);
end Add_Object_Pointer;
-----------------------
-- Build_Accept_Body --
-----------------------
function Build_Accept_Body (Astat : Node_Id) return Node_Id is
Loc : constant Source_Ptr := Sloc (Astat);
Stats : constant Node_Id := Handled_Statement_Sequence (Astat);
New_S : Node_Id;
Hand : Node_Id;
Call : Node_Id;
Ohandle : Node_Id;
begin
-- At the end of the statement sequence, Complete_Rendezvous is called.
-- A label skipping the Complete_Rendezvous, and all other accept
-- processing, has already been added for the expansion of requeue
-- statements. The Sloc is copied from the last statement since it
-- is really part of this last statement.
Call :=
Build_Runtime_Call
(Sloc (Last (Statements (Stats))), RE_Complete_Rendezvous);
Insert_Before (Last (Statements (Stats)), Call);
Analyze (Call);
-- Ada 2022 (AI12-0279)
if Has_Yield_Aspect (Entity (Entry_Direct_Name (Astat)))
and then RTE_Available (RE_Yield)
then
Insert_Action_After (Call,
Make_Procedure_Call_Statement (Loc,
New_Occurrence_Of (RTE (RE_Yield), Loc)));
end if;
-- If exception handlers are present, then append Complete_Rendezvous
-- calls to the handlers, and construct the required outer block. As
-- above, the Sloc is copied from the last statement in the sequence.
if Present (Exception_Handlers (Stats)) then
Hand := First (Exception_Handlers (Stats));
while Present (Hand) loop
Call :=
Build_Runtime_Call
(Sloc (Last (Statements (Hand))), RE_Complete_Rendezvous);
Append (Call, Statements (Hand));
Analyze (Call);
-- Ada 2022 (AI12-0279)
if Has_Yield_Aspect (Entity (Entry_Direct_Name (Astat)))
and then RTE_Available (RE_Yield)
then
Insert_Action_After (Call,
Make_Procedure_Call_Statement (Loc,
New_Occurrence_Of (RTE (RE_Yield), Loc)));
end if;
Next (Hand);
end loop;
New_S :=
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (
Make_Block_Statement (Loc,
Handled_Statement_Sequence => Stats)));
else
New_S := Stats;
end if;
-- At this stage we know that the new statement sequence does
-- not have an exception handler part, so we supply one to call
-- Exceptional_Complete_Rendezvous. This handler is
-- when all others =>
-- Exceptional_Complete_Rendezvous (Get_GNAT_Exception);
-- We handle Abort_Signal to make sure that we properly catch the abort
-- case and wake up the caller.
Call :=
Make_Procedure_Call_Statement (Sloc (Stats),
Name => New_Occurrence_Of (
RTE (RE_Exceptional_Complete_Rendezvous), Sloc (Stats)),
Parameter_Associations => New_List (
Make_Function_Call (Sloc (Stats),
Name =>
New_Occurrence_Of
(RTE (RE_Get_GNAT_Exception), Sloc (Stats)))));
Ohandle := Make_Others_Choice (Loc);
Set_All_Others (Ohandle);
Set_Exception_Handlers (New_S,
New_List (
Make_Implicit_Exception_Handler (Loc,
Exception_Choices => New_List (Ohandle),
Statements => New_List (Call))));
-- Ada 2022 (AI12-0279)
if Has_Yield_Aspect (Entity (Entry_Direct_Name (Astat)))
and then RTE_Available (RE_Yield)
then
Insert_Action_After (Call,
Make_Procedure_Call_Statement (Loc,
New_Occurrence_Of (RTE (RE_Yield), Loc)));
end if;
Set_Parent (New_S, Astat); -- temp parent for Analyze call
Analyze_Exception_Handlers (Exception_Handlers (New_S));
Expand_Exception_Handlers (New_S);
-- Exceptional_Complete_Rendezvous must be called with abort still
-- deferred, which is the case for a "when all others" handler.
return New_S;
end Build_Accept_Body;
-----------------------------------
-- Build_Activation_Chain_Entity --
-----------------------------------
procedure Build_Activation_Chain_Entity (N : Node_Id) is
function Has_Activation_Chain (Stmt : Node_Id) return Boolean;
-- Determine whether an extended return statement has activation chain
--------------------------
-- Has_Activation_Chain --
--------------------------
function Has_Activation_Chain (Stmt : Node_Id) return Boolean is
Decl : Node_Id;
begin
Decl := First (Return_Object_Declarations (Stmt));
while Present (Decl) loop
if Nkind (Decl) = N_Object_Declaration
and then Chars (Defining_Identifier (Decl)) = Name_uChain
then
return True;
end if;
Next (Decl);
end loop;
return False;
end Has_Activation_Chain;
-- Local variables
Context : Node_Id;
Context_Id : Entity_Id;
Decls : List_Id;
-- Start of processing for Build_Activation_Chain_Entity
begin
-- No action needed if the run-time has no tasking support
if Global_No_Tasking then
return;
end if;
-- Activation chain is never used for sequential elaboration policy, see
-- comment for Create_Restricted_Task_Sequential in s-tarest.ads).
if Partition_Elaboration_Policy = 'S' then
return;
end if;
Find_Enclosing_Context (N, Context, Context_Id, Decls);
-- If activation chain entity has not been declared already, create one
if Nkind (Context) = N_Extended_Return_Statement
or else No (Activation_Chain_Entity (Context))
then
-- Since extended return statements do not store the entity of the
-- chain, examine the return object declarations to avoid creating
-- a duplicate.
if Nkind (Context) = N_Extended_Return_Statement
and then Has_Activation_Chain (Context)
then
return;
end if;
declare
Loc : constant Source_Ptr := Sloc (Context);
Chain : Entity_Id;
Decl : Node_Id;
begin
Chain := Make_Defining_Identifier (Sloc (N), Name_uChain);
-- Note: An extended return statement is not really a task
-- activator, but it does have an activation chain on which to
-- store the tasks temporarily. On successful return, the tasks
-- on this chain are moved to the chain passed in by the caller.
-- We do not build an Activation_Chain_Entity for an extended
-- return statement, because we do not want to build a call to
-- Activate_Tasks. Task activation is the responsibility of the
-- caller.
if Nkind (Context) /= N_Extended_Return_Statement then
Set_Activation_Chain_Entity (Context, Chain);
end if;
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Chain,
Aliased_Present => True,
Object_Definition =>
New_Occurrence_Of (RTE (RE_Activation_Chain), Loc));
Prepend_To (Decls, Decl);
-- Ensure that _chain appears in the proper scope of the context
if Context_Id /= Current_Scope then
Push_Scope (Context_Id);
Analyze (Decl);
Pop_Scope;
else
Analyze (Decl);
end if;
end;
end if;
end Build_Activation_Chain_Entity;
----------------------------
-- Build_Barrier_Function --
----------------------------
function Build_Barrier_Function
(N : Node_Id;
Ent : Entity_Id;
Pid : Entity_Id) return Node_Id
is
Ent_Formals : constant Node_Id := Entry_Body_Formal_Part (N);
Cond : constant Node_Id := Condition (Ent_Formals);
Loc : constant Source_Ptr := Sloc (Cond);
Func_Id : constant Entity_Id := Barrier_Function (Ent);
Op_Decls : constant List_Id := New_List;
Stmt : Node_Id;
Func_Body : Node_Id;
begin
-- Add a declaration for the Protection object, renaming declarations
-- for the discriminals and privals and finally a declaration for the
-- entry family index (if applicable).
Install_Private_Data_Declarations (Sloc (N),
Spec_Id => Func_Id,
Conc_Typ => Pid,
Body_Nod => N,
Decls => Op_Decls,
Barrier => True,
Family => Ekind (Ent) = E_Entry_Family);
-- If compiling with -fpreserve-control-flow, make sure we insert an
-- IF statement so that the back-end knows to generate a conditional
-- branch instruction, even if the condition is just the name of a
-- boolean object. Note that Expand_N_If_Statement knows to preserve
-- such redundant IF statements under -fpreserve-control-flow
-- (whether coming from this routine, or directly from source).
if Opt.Suppress_Control_Flow_Optimizations then
Stmt :=
Make_Implicit_If_Statement (Cond,
Condition => Cond,
Then_Statements => New_List (
Make_Simple_Return_Statement (Loc,
New_Occurrence_Of (Standard_True, Loc))),
Else_Statements => New_List (
Make_Simple_Return_Statement (Loc,
New_Occurrence_Of (Standard_False, Loc))));
else
Stmt := Make_Simple_Return_Statement (Loc, Cond);
end if;
-- Note: the condition in the barrier function needs to be properly
-- processed for the C/Fortran boolean possibility, but this happens
-- automatically since the return statement does this normalization.
Func_Body :=
Make_Subprogram_Body (Loc,
Specification =>
Build_Barrier_Function_Specification (Loc,
Make_Defining_Identifier (Loc, Chars (Func_Id))),
Declarations => Op_Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (Stmt)));
Set_Is_Entry_Barrier_Function (Func_Body);
return Func_Body;
end Build_Barrier_Function;
------------------------------------------
-- Build_Barrier_Function_Specification --
------------------------------------------
function Build_Barrier_Function_Specification
(Loc : Source_Ptr;
Def_Id : Entity_Id) return Node_Id
is
begin
Set_Debug_Info_Needed (Def_Id);
return
Make_Function_Specification (Loc,
Defining_Unit_Name => Def_Id,
Parameter_Specifications => New_List (
Make_Parameter_Specification (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uO),
Parameter_Type =>
New_Occurrence_Of (RTE (RE_Address), Loc)),
Make_Parameter_Specification (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uE),
Parameter_Type =>
New_Occurrence_Of (RTE (RE_Protected_Entry_Index), Loc))),
Result_Definition =>
New_Occurrence_Of (Standard_Boolean, Loc));
end Build_Barrier_Function_Specification;
--------------------------
-- Build_Call_With_Task --
--------------------------
function Build_Call_With_Task
(N : Node_Id;
E : Entity_Id) return Node_Id
is
Loc : constant Source_Ptr := Sloc (N);
begin
return
Make_Function_Call (Loc,
Name => New_Occurrence_Of (E, Loc),
Parameter_Associations => New_List (Concurrent_Ref (N)));
end Build_Call_With_Task;
-----------------------------
-- Build_Class_Wide_Master --
-----------------------------
procedure Build_Class_Wide_Master (Typ : Entity_Id) is
Loc : constant Source_Ptr := Sloc (Typ);
Master_Decl : Node_Id;
Master_Id : Entity_Id;
Master_Scope : Entity_Id;
Name_Id : Node_Id;
Related_Node : Node_Id;
Ren_Decl : Node_Id;
begin
-- No action needed if the run-time has no tasking support
if Global_No_Tasking then
return;
end if;
-- Find the declaration that created the access type, which is either a
-- type declaration, or an object declaration with an access definition,
-- in which case the type is anonymous.
if Is_Itype (Typ) then
Related_Node := Associated_Node_For_Itype (Typ);
else
Related_Node := Parent (Typ);
end if;
Master_Scope := Find_Master_Scope (Typ);
-- Nothing to do if the master scope already contains a _master entity.
-- The only exception to this is the following scenario:
-- Source_Scope
-- Transient_Scope_1
-- _master
-- Transient_Scope_2
-- use of master
-- In this case the source scope is marked as having the master entity
-- even though the actual declaration appears inside an inner scope. If
-- the second transient scope requires a _master, it cannot use the one
-- already declared because the entity is not visible.
Name_Id := Make_Identifier (Loc, Name_uMaster);
Master_Decl := Empty;
if not Has_Master_Entity (Master_Scope)
or else No (Current_Entity_In_Scope (Name_Id))
then
declare
Ins_Nod : Node_Id;
begin
Set_Has_Master_Entity (Master_Scope);
Master_Decl := Build_Master_Declaration (Loc);
-- Ensure that the master declaration is placed before its use
Ins_Nod := Find_Hook_Context (Related_Node);
while not Is_List_Member (Ins_Nod) loop
Ins_Nod := Parent (Ins_Nod);
end loop;
Insert_Before (First (List_Containing (Ins_Nod)), Master_Decl);
Analyze (Master_Decl);
-- Mark the containing scope as a task master. Masters associated
-- with return statements are already marked at this stage (see
-- Analyze_Subprogram_Body).
if Ekind (Current_Scope) /= E_Return_Statement then
declare
Par : Node_Id := Related_Node;
begin
while Nkind (Par) /= N_Compilation_Unit loop
Par := Parent (Par);
-- If we fall off the top, we are at the outer level,
-- and the environment task is our effective master,
-- so nothing to mark.
if Nkind (Par) in
N_Block_Statement | N_Subprogram_Body | N_Task_Body
then
Set_Is_Task_Master (Par);
exit;
end if;
end loop;
end;
end if;
end;
end if;
Master_Id :=
Make_Defining_Identifier (Loc, New_External_Name (Chars (Typ), 'M'));
-- Generate:
-- typeMnn renames _master;
Ren_Decl :=
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier => Master_Id,
Subtype_Mark => New_Occurrence_Of (Standard_Integer, Loc),
Name => Name_Id);
-- If the master is declared locally, add the renaming declaration
-- immediately after it, to prevent access-before-elaboration in the
-- back-end.
if Present (Master_Decl) then
Insert_After (Master_Decl, Ren_Decl);
Analyze (Ren_Decl);
else
Insert_Action (Related_Node, Ren_Decl);
end if;
Set_Master_Id (Typ, Master_Id);
end Build_Class_Wide_Master;
----------------------------
-- Build_Contract_Wrapper --
----------------------------
procedure Build_Contract_Wrapper (E : Entity_Id; Decl : Node_Id) is
Conc_Typ : constant Entity_Id := Scope (E);
Loc : constant Source_Ptr := Sloc (E);
procedure Add_Discriminant_Renamings
(Obj_Id : Entity_Id;
Decls : List_Id);
-- Add renaming declarations for all discriminants of concurrent type
-- Conc_Typ. Obj_Id is the entity of the wrapper formal parameter which
-- represents the concurrent object.
procedure Add_Matching_Formals
(Formals : List_Id;
Actuals : in out List_Id);
-- Add formal parameters that match those of entry E to list Formals.
-- The routine also adds matching actuals for the new formals to list
-- Actuals.
procedure Transfer_Pragma (Prag : Node_Id; To : in out List_Id);
-- Relocate pragma Prag to list To. The routine creates a new list if
-- To does not exist.
--------------------------------
-- Add_Discriminant_Renamings --
--------------------------------
procedure Add_Discriminant_Renamings
(Obj_Id : Entity_Id;
Decls : List_Id)
is
Discr : Entity_Id;
begin
-- Inspect the discriminants of the concurrent type and generate a
-- renaming for each one.
if Has_Discriminants (Conc_Typ) then
Discr := First_Discriminant (Conc_Typ);
while Present (Discr) loop
Prepend_To (Decls,
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Chars (Discr)),
Subtype_Mark =>
New_Occurrence_Of (Etype (Discr), Loc),
Name =>
Make_Selected_Component (Loc,
Prefix => New_Occurrence_Of (Obj_Id, Loc),
Selector_Name =>
Make_Identifier (Loc, Chars (Discr)))));
Next_Discriminant (Discr);
end loop;
end if;
end Add_Discriminant_Renamings;
--------------------------
-- Add_Matching_Formals --
--------------------------
procedure Add_Matching_Formals
(Formals : List_Id;
Actuals : in out List_Id)
is
Formal : Entity_Id;
New_Formal : Entity_Id;
begin
-- Inspect the formal parameters of the entry and generate a new
-- matching formal with the same name for the wrapper. A reference
-- to the new formal becomes an actual in the entry call.
Formal := First_Formal (E);
while Present (Formal) loop
New_Formal := Make_Defining_Identifier (Loc, Chars (Formal));
Append_To (Formals,
Make_Parameter_Specification (Loc,
Defining_Identifier => New_Formal,
In_Present => In_Present (Parent (Formal)),
Out_Present => Out_Present (Parent (Formal)),
Parameter_Type =>
New_Occurrence_Of (Etype (Formal), Loc)));
if No (Actuals) then
Actuals := New_List;
end if;
Append_To (Actuals, New_Occurrence_Of (New_Formal, Loc));
Next_Formal (Formal);
end loop;
end Add_Matching_Formals;
---------------------
-- Transfer_Pragma --
---------------------
procedure Transfer_Pragma (Prag : Node_Id; To : in out List_Id) is
New_Prag : Node_Id;
begin
if No (To) then
To := New_List;
end if;
New_Prag := Relocate_Node (Prag);
Set_Analyzed (New_Prag, False);
Append (New_Prag, To);
end Transfer_Pragma;
-- Local variables
Items : constant Node_Id := Contract (E);
Actuals : List_Id := No_List;
Call : Node_Id;
Call_Nam : Node_Id;
Decls : List_Id := No_List;
Formals : List_Id;
Has_Pragma : Boolean := False;
Index_Id : Entity_Id;
Obj_Id : Entity_Id;
Prag : Node_Id;
Wrapper_Id : Entity_Id;
-- Start of processing for Build_Contract_Wrapper
begin
-- This routine generates a specialized wrapper for a protected or task
-- entry [family] which implements precondition/postcondition semantics.
-- Preconditions and case guards of contract cases are checked before
-- the protected action or rendezvous takes place. Postconditions and
-- consequences of contract cases are checked after the protected action
-- or rendezvous takes place. The structure of the generated wrapper is
-- as follows:
-- procedure Wrapper
-- (Obj_Id : Conc_Typ; -- concurrent object
-- [Index : Index_Typ;] -- index of entry family
-- [Formal_1 : ...; -- parameters of original entry
-- Formal_N : ...])
-- is
-- [Discr_1 : ... renames Obj_Id.Discr_1; -- discriminant
-- Discr_N : ... renames Obj_Id.Discr_N;] -- renamings
-- <precondition checks>
-- <case guard checks>
-- procedure _Postconditions is
-- begin
-- <postcondition checks>
-- <consequence checks>
-- end _Postconditions;
-- begin
-- Entry_Call (Obj_Id, [Index,] [Formal_1, Formal_N]);
-- _Postconditions;
-- end Wrapper;
-- Create the wrapper only when the entry has at least one executable
-- contract item such as contract cases, precondition or postcondition.
if Present (Items) then
-- Inspect the list of pre/postconditions and transfer all available
-- pragmas to the declarative list of the wrapper.
Prag := Pre_Post_Conditions (Items);
while Present (Prag) loop
if Pragma_Name_Unmapped (Prag) in Name_Postcondition
| Name_Precondition
and then Is_Checked (Prag)
then
Has_Pragma := True;
Transfer_Pragma (Prag, To => Decls);
end if;
Prag := Next_Pragma (Prag);
end loop;
-- Inspect the list of test/contract cases and transfer only contract
-- cases pragmas to the declarative part of the wrapper.
Prag := Contract_Test_Cases (Items);
while Present (Prag) loop
if Pragma_Name (Prag) = Name_Contract_Cases
and then Is_Checked (Prag)
then
Has_Pragma := True;
Transfer_Pragma (Prag, To => Decls);
end if;
Prag := Next_Pragma (Prag);
end loop;
end if;
-- The entry lacks executable contract items and a wrapper is not needed
if not Has_Pragma then
return;
end if;
-- Create the profile of the wrapper. The first formal parameter is the
-- concurrent object.
Obj_Id :=
Make_Defining_Identifier (Loc,
Chars => New_External_Name (Chars (Conc_Typ), 'A'));
Formals := New_List (
Make_Parameter_Specification (Loc,
Defining_Identifier => Obj_Id,
Out_Present => True,
In_Present => True,
Parameter_Type => New_Occurrence_Of (Conc_Typ, Loc)));
-- Construct the call to the original entry. The call will be gradually
-- augmented with an optional entry index and extra parameters.
Call_Nam :=
Make_Selected_Component (Loc,
Prefix => New_Occurrence_Of (Obj_Id, Loc),
Selector_Name => New_Occurrence_Of (E, Loc));
-- When creating a wrapper for an entry family, the second formal is the
-- entry index.
if Ekind (E) = E_Entry_Family then
Index_Id := Make_Defining_Identifier (Loc, Name_I);
Append_To (Formals,
Make_Parameter_Specification (Loc,
Defining_Identifier => Index_Id,
Parameter_Type =>
New_Occurrence_Of (Entry_Index_Type (E), Loc)));
-- The call to the original entry becomes an indexed component to
-- accommodate the entry index.
Call_Nam :=
Make_Indexed_Component (Loc,
Prefix => Call_Nam,
Expressions => New_List (New_Occurrence_Of (Index_Id, Loc)));
end if;
-- Add formal parameters to match those of the entry and build actuals
-- for the entry call.
Add_Matching_Formals (Formals, Actuals);
Call :=
Make_Procedure_Call_Statement (Loc,
Name => Call_Nam,
Parameter_Associations => Actuals);
-- Add renaming declarations for the discriminants of the enclosing type
-- as the various contract items may reference them.
Add_Discriminant_Renamings (Obj_Id, Decls);
Wrapper_Id :=
Make_Defining_Identifier (Loc, New_External_Name (Chars (E), 'E'));
Set_Contract_Wrapper (E, Wrapper_Id);
Set_Is_Entry_Wrapper (Wrapper_Id);
-- The wrapper body is analyzed when the enclosing type is frozen
Append_Freeze_Action (Defining_Entity (Decl),
Make_Subprogram_Body (Loc,
Specification =>
Make_Procedure_Specification (Loc,
Defining_Unit_Name => Wrapper_Id,
Parameter_Specifications => Formals),
Declarations => Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (Call))));
end Build_Contract_Wrapper;
--------------------------------
-- Build_Corresponding_Record --
--------------------------------
function Build_Corresponding_Record
(N : Node_Id;
Ctyp : Entity_Id;
Loc : Source_Ptr) return Node_Id
is
Rec_Ent : constant Entity_Id :=
Make_Defining_Identifier
(Loc, New_External_Name (Chars (Ctyp), 'V'));
Disc : Entity_Id;
Dlist : List_Id;
New_Disc : Entity_Id;
Cdecls : List_Id;
begin
Set_Corresponding_Record_Type (Ctyp, Rec_Ent);
Mutate_Ekind (Rec_Ent, E_Record_Type);
Set_Has_Delayed_Freeze (Rec_Ent, Has_Delayed_Freeze (Ctyp));
Set_Is_Concurrent_Record_Type (Rec_Ent, True);
Set_Corresponding_Concurrent_Type (Rec_Ent, Ctyp);
Set_Stored_Constraint (Rec_Ent, No_Elist);
Cdecls := New_List;
-- Use discriminals to create list of discriminants for record, and
-- create new discriminals for use in default expressions, etc. It is
-- worth noting that a task discriminant gives rise to 5 entities;
-- a) The original discriminant.
-- b) The discriminal for use in the task.
-- c) The discriminant of the corresponding record.
-- d) The discriminal for the init proc of the corresponding record.
-- e) The local variable that renames the discriminant in the procedure
-- for the task body.
-- In fact the discriminals b) are used in the renaming declarations
-- for e). See details in einfo (Handling of Discriminants).
if Present (Discriminant_Specifications (N)) then
Dlist := New_List;
Disc := First_Discriminant (Ctyp);
while Present (Disc) loop
New_Disc := CR_Discriminant (Disc);
Append_To (Dlist,
Make_Discriminant_Specification (Loc,
Defining_Identifier => New_Disc,
Discriminant_Type =>
New_Occurrence_Of (Etype (Disc), Loc),
Expression =>
New_Copy (Discriminant_Default_Value (Disc))));
Next_Discriminant (Disc);
end loop;
else
Dlist := No_List;
end if;
-- Now we can construct the record type declaration. Note that this
-- record is "limited tagged". It is "limited" to reflect the underlying
-- limitedness of the task or protected object that it represents, and
-- ensuring for example that it is properly passed by reference. It is
-- "tagged" to give support to dispatching calls through interfaces. We
-- propagate here the list of interfaces covered by the concurrent type
-- (Ada 2005: AI-345).
return
Make_Full_Type_Declaration (Loc,
Defining_Identifier => Rec_Ent,
Discriminant_Specifications => Dlist,
Type_Definition =>
Make_Record_Definition (Loc,
Component_List =>
Make_Component_List (Loc, Component_Items => Cdecls),
Tagged_Present =>
Ada_Version >= Ada_2005 and then Is_Tagged_Type (Ctyp),
Interface_List => Interface_List (N),
Limited_Present => True));
end Build_Corresponding_Record;
---------------------------------
-- Build_Dispatching_Tag_Check --
---------------------------------
function Build_Dispatching_Tag_Check
(K : Entity_Id;
N : Node_Id) return Node_Id
is
Loc : constant Source_Ptr := Sloc (N);
begin
return
Make_Op_Or (Loc,
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (K, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_TK_Limited_Tagged), Loc)),
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (K, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_TK_Tagged), Loc)));
end Build_Dispatching_Tag_Check;
----------------------------------
-- Build_Entry_Count_Expression --
----------------------------------
function Build_Entry_Count_Expression
(Concurrent_Type : Node_Id;
Component_List : List_Id;
Loc : Source_Ptr) return Node_Id
is
Eindx : Nat;
Ent : Entity_Id;
Ecount : Node_Id;
Comp : Node_Id;
Lo : Node_Id;
Hi : Node_Id;
Typ : Entity_Id;
Large : Boolean;
begin
-- Count number of non-family entries
Eindx := 0;
Ent := First_Entity (Concurrent_Type);
while Present (Ent) loop
if Ekind (Ent) = E_Entry then
Eindx := Eindx + 1;
end if;
Next_Entity (Ent);
end loop;
Ecount := Make_Integer_Literal (Loc, Eindx);
-- Loop through entry families building the addition nodes
Ent := First_Entity (Concurrent_Type);
Comp := First (Component_List);
while Present (Ent) loop
if Ekind (Ent) = E_Entry_Family then
while Chars (Ent) /= Chars (Defining_Identifier (Comp)) loop
Next (Comp);
end loop;
Typ := Entry_Index_Type (Ent);
Hi := Type_High_Bound (Typ);
Lo := Type_Low_Bound (Typ);
Large := Is_Potentially_Large_Family
(Base_Type (Typ), Concurrent_Type, Lo, Hi);
Ecount :=
Make_Op_Add (Loc,
Left_Opnd => Ecount,
Right_Opnd =>
Family_Size (Loc, Hi, Lo, Concurrent_Type, Large));
end if;
Next_Entity (Ent);
end loop;
return Ecount;
end Build_Entry_Count_Expression;
------------------------------
-- Build_Master_Declaration --
------------------------------
function Build_Master_Declaration (Loc : Source_Ptr) return Node_Id is
Master_Decl : Node_Id;
begin
-- Generate a dummy master if tasks or tasking hierarchies are
-- prohibited.
-- _Master : constant Integer := Library_Task_Level;
if not Tasking_Allowed
or else Restrictions.Set (No_Task_Hierarchy)
or else not RTE_Available (RE_Current_Master)
then
Master_Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uMaster),
Constant_Present => True,
Object_Definition =>
New_Occurrence_Of (Standard_Integer, Loc),
Expression =>
Make_Integer_Literal (Loc, Library_Task_Level));
-- Generate:
-- _master : constant Integer := Current_Master.all;
else
Master_Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uMaster),
Constant_Present => True,
Object_Definition =>
New_Occurrence_Of (Standard_Integer, Loc),
Expression =>
Make_Explicit_Dereference (Loc,
New_Occurrence_Of (RTE (RE_Current_Master), Loc)));
end if;
return Master_Decl;
end Build_Master_Declaration;
---------------------------
-- Build_Parameter_Block --
---------------------------
function Build_Parameter_Block
(Loc : Source_Ptr;
Actuals : List_Id;
Formals : List_Id;
Decls : List_Id) return Entity_Id
is
Actual : Entity_Id;
Comp_Nam : Node_Id;
Comps : List_Id;
Formal : Entity_Id;
Has_Comp : Boolean := False;
Rec_Nam : Node_Id;
begin
Actual := First (Actuals);
Comps := New_List;
Formal := Defining_Identifier (First (Formals));
while Present (Actual) loop
if not Is_Controlling_Actual (Actual) then
-- Generate:
-- type Ann is access all <actual-type>
Comp_Nam := Make_Temporary (Loc, 'A');
Set_Is_Param_Block_Component_Type (Comp_Nam);
Append_To (Decls,
Make_Full_Type_Declaration (Loc,
Defining_Identifier => Comp_Nam,
Type_Definition =>
Make_Access_To_Object_Definition (Loc,
All_Present => True,
Constant_Present => Ekind (Formal) = E_In_Parameter,
Subtype_Indication =>
New_Occurrence_Of (Etype (Actual), Loc))));
-- Generate:
-- Param : Ann;
Append_To (Comps,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Chars (Formal)),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present =>
False,
Subtype_Indication =>
New_Occurrence_Of (Comp_Nam, Loc))));
Has_Comp := True;
end if;
Next_Actual (Actual);
Next_Formal_With_Extras (Formal);
end loop;
Rec_Nam := Make_Temporary (Loc, 'P');
if Has_Comp then
-- Generate:
-- type Pnn is record
-- Param1 : Ann1;
-- ...
-- ParamN : AnnN;
-- where Pnn is a parameter wrapping record, Param1 .. ParamN are
-- the original parameter names and Ann1 .. AnnN are the access to
-- actual types.
Append_To (Decls,
Make_Full_Type_Declaration (Loc,
Defining_Identifier =>
Rec_Nam,
Type_Definition =>
Make_Record_Definition (Loc,
Component_List =>
Make_Component_List (Loc, Comps))));
else
-- Generate:
-- type Pnn is null record;
Append_To (Decls,
Make_Full_Type_Declaration (Loc,
Defining_Identifier =>
Rec_Nam,
Type_Definition =>
Make_Record_Definition (Loc,
Null_Present => True,
Component_List => Empty)));
end if;
return Rec_Nam;
end Build_Parameter_Block;
--------------------------------------
-- Build_Renamed_Formal_Declaration --
--------------------------------------
function Build_Renamed_Formal_Declaration
(New_F : Entity_Id;
Formal : Entity_Id;
Comp : Entity_Id;
Renamed_Formal : Node_Id) return Node_Id
is
Loc : constant Source_Ptr := Sloc (New_F);
Decl : Node_Id;
begin
-- If the formal is a tagged incomplete type, it is already passed
-- by reference, so it is sufficient to rename the pointer component
-- that corresponds to the actual. Otherwise we need to dereference
-- the pointer component to obtain the actual.
if Is_Incomplete_Type (Etype (Formal))
and then Is_Tagged_Type (Etype (Formal))
then
Decl :=
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier => New_F,
Subtype_Mark => New_Occurrence_Of (Etype (Comp), Loc),
Name => Renamed_Formal);
else
Decl :=
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier => New_F,
Subtype_Mark => New_Occurrence_Of (Etype (Formal), Loc),
Name =>
Make_Explicit_Dereference (Loc, Renamed_Formal));
end if;
return Decl;
end Build_Renamed_Formal_Declaration;
--------------------------
-- Build_Wrapper_Bodies --
--------------------------
procedure Build_Wrapper_Bodies
(Loc : Source_Ptr;
Typ : Entity_Id;
N : Node_Id)
is
Rec_Typ : Entity_Id;
function Build_Wrapper_Body
(Loc : Source_Ptr;
Subp_Id : Entity_Id;
Obj_Typ : Entity_Id;
Formals : List_Id) return Node_Id;
-- Ada 2005 (AI-345): Build the body that wraps a primitive operation
-- associated with a protected or task type. Subp_Id is the subprogram
-- name which will be wrapped. Obj_Typ is the type of the new formal
-- parameter which handles dispatching and object notation. Formals are
-- the original formals of Subp_Id which will be explicitly replicated.
------------------------
-- Build_Wrapper_Body --
------------------------
function Build_Wrapper_Body
(Loc : Source_Ptr;
Subp_Id : Entity_Id;
Obj_Typ : Entity_Id;
Formals : List_Id) return Node_Id
is
Body_Spec : Node_Id;
begin
Body_Spec := Build_Wrapper_Spec (Subp_Id, Obj_Typ, Formals);
-- The subprogram is not overriding or is not a primitive declared
-- between two views.
if No (Body_Spec) then
return Empty;
end if;
declare
Actuals : List_Id := No_List;
Conv_Id : Node_Id;
First_Form : Node_Id;
Formal : Node_Id;
Nam : Node_Id;
begin
-- Map formals to actuals. Use the list built for the wrapper
-- spec, skipping the object notation parameter.
First_Form := First (Parameter_Specifications (Body_Spec));
Formal := First_Form;
Next (Formal);
if Present (Formal) then
Actuals := New_List;
while Present (Formal) loop
Append_To (Actuals,
Make_Identifier (Loc,
Chars => Chars (Defining_Identifier (Formal))));
Next (Formal);
end loop;
end if;
-- Special processing for primitives declared between a private
-- type and its completion: the wrapper needs a properly typed
-- parameter if the wrapped operation has a controlling first
-- parameter. Note that this might not be the case for a function
-- with a controlling result.
if Is_Private_Primitive_Subprogram (Subp_Id) then
if No (Actuals) then
Actuals := New_List;
end if;
if Is_Controlling_Formal (First_Formal (Subp_Id)) then
Prepend_To (Actuals,
Unchecked_Convert_To
(Corresponding_Concurrent_Type (Obj_Typ),
Make_Identifier (Loc, Name_uO)));
else
Prepend_To (Actuals,
Make_Identifier (Loc,
Chars => Chars (Defining_Identifier (First_Form))));
end if;
Nam := New_Occurrence_Of (Subp_Id, Loc);
else
-- An access-to-variable object parameter requires an explicit
-- dereference in the unchecked conversion. This case occurs
-- when a protected entry wrapper must override an interface
-- level procedure with interface access as first parameter.
-- O.all.Subp_Id (Formal_1, ..., Formal_N)
if Nkind (Parameter_Type (First_Form)) =
N_Access_Definition
then
Conv_Id :=
Make_Explicit_Dereference (Loc,
Prefix => Make_Identifier (Loc, Name_uO));
else
Conv_Id := Make_Identifier (Loc, Name_uO);
end if;
Nam :=
Make_Selected_Component (Loc,
Prefix =>
Unchecked_Convert_To
(Corresponding_Concurrent_Type (Obj_Typ), Conv_Id),
Selector_Name => New_Occurrence_Of (Subp_Id, Loc));
end if;
-- Create the subprogram body. For a function, the call to the
-- actual subprogram has to be converted to the corresponding
-- record if it is a controlling result.
if Ekind (Subp_Id) = E_Function then
declare
Res : Node_Id;
begin
Res :=
Make_Function_Call (Loc,
Name => Nam,
Parameter_Associations => Actuals);
if Has_Controlling_Result (Subp_Id) then
Res :=
Unchecked_Convert_To
(Corresponding_Record_Type (Etype (Subp_Id)), Res);
end if;
return
Make_Subprogram_Body (Loc,
Specification => Body_Spec,
Declarations => Empty_List,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (
Make_Simple_Return_Statement (Loc, Res))));
end;
else
return
Make_Subprogram_Body (Loc,
Specification => Body_Spec,
Declarations => Empty_List,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (
Make_Procedure_Call_Statement (Loc,
Name => Nam,
Parameter_Associations => Actuals))));
end if;
end;
end Build_Wrapper_Body;
-- Start of processing for Build_Wrapper_Bodies
begin
if Is_Concurrent_Type (Typ) then
Rec_Typ := Corresponding_Record_Type (Typ);
else
Rec_Typ := Typ;
end if;
-- Generate wrapper bodies for a concurrent type which implements an
-- interface.
if Present (Interfaces (Rec_Typ)) then
declare
Insert_Nod : Node_Id;
Prim : Entity_Id;
Prim_Elmt : Elmt_Id;
Prim_Decl : Node_Id;
Subp : Entity_Id;
Wrap_Body : Node_Id;
Wrap_Id : Entity_Id;
begin
Insert_Nod := N;
-- Examine all primitive operations of the corresponding record
-- type, looking for wrapper specs. Generate bodies in order to
-- complete them.
Prim_Elmt := First_Elmt (Primitive_Operations (Rec_Typ));
while Present (Prim_Elmt) loop
Prim := Node (Prim_Elmt);
if (Ekind (Prim) = E_Function
or else Ekind (Prim) = E_Procedure)
and then Is_Primitive_Wrapper (Prim)
then
Subp := Wrapped_Entity (Prim);
Prim_Decl := Parent (Parent (Prim));
Wrap_Body :=
Build_Wrapper_Body (Loc,
Subp_Id => Subp,
Obj_Typ => Rec_Typ,
Formals => Parameter_Specifications (Parent (Subp)));
Wrap_Id := Defining_Unit_Name (Specification (Wrap_Body));
Set_Corresponding_Spec (Wrap_Body, Prim);
Set_Corresponding_Body (Prim_Decl, Wrap_Id);
Insert_After (Insert_Nod, Wrap_Body);
Insert_Nod := Wrap_Body;
Analyze (Wrap_Body);
end if;
Next_Elmt (Prim_Elmt);
end loop;
end;
end if;
end Build_Wrapper_Bodies;
------------------------
-- Build_Wrapper_Spec --
------------------------
function Build_Wrapper_Spec
(Subp_Id : Entity_Id;
Obj_Typ : Entity_Id;
Formals : List_Id) return Node_Id
is
function Overriding_Possible
(Iface_Op : Entity_Id;
Wrapper : Entity_Id) return Boolean;
-- Determine whether a primitive operation can be overridden by Wrapper.
-- Iface_Op is the candidate primitive operation of an interface type,
-- Wrapper is the generated entry wrapper.
function Replicate_Formals
(Loc : Source_Ptr;
Formals : List_Id) return List_Id;
-- An explicit parameter replication is required due to the Is_Entry_
-- Formal flag being set for all the formals of an entry. The explicit
-- replication removes the flag that would otherwise cause a different
-- path of analysis.
-------------------------
-- Overriding_Possible --
-------------------------
function Overriding_Possible
(Iface_Op : Entity_Id;
Wrapper : Entity_Id) return Boolean
is
Iface_Op_Spec : constant Node_Id := Parent (Iface_Op);
Wrapper_Spec : constant Node_Id := Parent (Wrapper);
function Type_Conformant_Parameters
(Iface_Op_Params : List_Id;
Wrapper_Params : List_Id) return Boolean;
-- Determine whether the parameters of the generated entry wrapper
-- and those of a primitive operation are type conformant. During
-- this check, the first parameter of the primitive operation is
-- skipped if it is a controlling argument: protected functions
-- may have a controlling result.
--------------------------------
-- Type_Conformant_Parameters --
--------------------------------
function Type_Conformant_Parameters
(Iface_Op_Params : List_Id;
Wrapper_Params : List_Id) return Boolean
is
Iface_Op_Param : Node_Id;
Iface_Op_Typ : Entity_Id;
Wrapper_Param : Node_Id;
Wrapper_Typ : Entity_Id;
begin
-- Skip the first (controlling) parameter of primitive operation
Iface_Op_Param := First (Iface_Op_Params);
if Present (First_Formal (Iface_Op))
and then Is_Controlling_Formal (First_Formal (Iface_Op))
then
Next (Iface_Op_Param);
end if;
Wrapper_Param := First (Wrapper_Params);
while Present (Iface_Op_Param)
and then Present (Wrapper_Param)
loop
Iface_Op_Typ := Find_Parameter_Type (Iface_Op_Param);
Wrapper_Typ := Find_Parameter_Type (Wrapper_Param);
-- The two parameters must be mode conformant
if not Conforming_Types
(Iface_Op_Typ, Wrapper_Typ, Mode_Conformant)
then
return False;
end if;
Next (Iface_Op_Param);
Next (Wrapper_Param);
end loop;
-- One of the lists is longer than the other
if Present (Iface_Op_Param) or else Present (Wrapper_Param) then
return False;
end if;
return True;
end Type_Conformant_Parameters;
-- Start of processing for Overriding_Possible
begin
if Chars (Iface_Op) /= Chars (Wrapper) then
return False;
end if;
-- If an inherited subprogram is implemented by a protected procedure
-- or an entry, then the first parameter of the inherited subprogram
-- must be of mode OUT or IN OUT, or access-to-variable parameter.
if Ekind (Iface_Op) = E_Procedure
and then Present (Parameter_Specifications (Iface_Op_Spec))
then
declare
Obj_Param : constant Node_Id :=
First (Parameter_Specifications (Iface_Op_Spec));
begin
if not Out_Present (Obj_Param)
and then Nkind (Parameter_Type (Obj_Param)) /=
N_Access_Definition
then
return False;
end if;
end;
end if;
return
Type_Conformant_Parameters
(Parameter_Specifications (Iface_Op_Spec),
Parameter_Specifications (Wrapper_Spec));
end Overriding_Possible;
-----------------------
-- Replicate_Formals --
-----------------------
function Replicate_Formals
(Loc : Source_Ptr;
Formals : List_Id) return List_Id
is
New_Formals : constant List_Id := New_List;
Formal : Node_Id;
Param_Type : Node_Id;
begin
Formal := First (Formals);
-- Skip the object parameter when dealing with primitives declared
-- between two views.
if Is_Private_Primitive_Subprogram (Subp_Id)
and then not Has_Controlling_Result (Subp_Id)
then
Next (Formal);
end if;
while Present (Formal) loop
-- Create an explicit copy of the entry parameter
-- When creating the wrapper subprogram for a primitive operation
-- of a protected interface we must construct an equivalent
-- signature to that of the overriding operation. For regular
-- parameters we can just use the type of the formal, but for
-- access to subprogram parameters we need to reanalyze the
-- parameter type to create local entities for the signature of
-- the subprogram type. Using the entities of the overriding
-- subprogram will result in out-of-scope errors in the back-end.
if Nkind (Parameter_Type (Formal)) = N_Access_Definition then
Param_Type := Copy_Separate_Tree (Parameter_Type (Formal));
else
Param_Type :=
New_Occurrence_Of (Etype (Parameter_Type (Formal)), Loc);
end if;
Append_To (New_Formals,
Make_Parameter_Specification (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc,
Chars => Chars (Defining_Identifier (Formal))),
In_Present => In_Present (Formal),
Out_Present => Out_Present (Formal),
Null_Exclusion_Present => Null_Exclusion_Present (Formal),
Parameter_Type => Param_Type));
Next (Formal);
end loop;
return New_Formals;
end Replicate_Formals;
-- Local variables
Loc : constant Source_Ptr := Sloc (Subp_Id);
First_Param : Node_Id := Empty;
Iface : Entity_Id;
Iface_Elmt : Elmt_Id;
Iface_Op : Entity_Id;
Iface_Op_Elmt : Elmt_Id;
Overridden_Subp : Entity_Id;
-- Start of processing for Build_Wrapper_Spec
begin
-- No point in building wrappers for untagged concurrent types
pragma Assert (Is_Tagged_Type (Obj_Typ));
-- Check if this subprogram has a profile that matches some interface
-- primitive.
Check_Synchronized_Overriding (Subp_Id, Overridden_Subp);
if Present (Overridden_Subp) then
First_Param :=
First (Parameter_Specifications (Parent (Overridden_Subp)));
-- An entry or a protected procedure can override a routine where the
-- controlling formal is either IN OUT, OUT or is of access-to-variable
-- type. Since the wrapper must have the exact same signature as that of
-- the overridden subprogram, we try to find the overriding candidate
-- and use its controlling formal.
-- Check every implemented interface
elsif Present (Interfaces (Obj_Typ)) then
Iface_Elmt := First_Elmt (Interfaces (Obj_Typ));
Search : while Present (Iface_Elmt) loop
Iface := Node (Iface_Elmt);
-- Check every interface primitive
if Present (Primitive_Operations (Iface)) then
Iface_Op_Elmt := First_Elmt (Primitive_Operations (Iface));
while Present (Iface_Op_Elmt) loop
Iface_Op := Node (Iface_Op_Elmt);
-- Ignore predefined primitives
if not Is_Predefined_Dispatching_Operation (Iface_Op) then
Iface_Op := Ultimate_Alias (Iface_Op);
-- The current primitive operation can be overridden by
-- the generated entry wrapper.
if Overriding_Possible (Iface_Op, Subp_Id) then
First_Param :=
First (Parameter_Specifications (Parent (Iface_Op)));
exit Search;
end if;
end if;
Next_Elmt (Iface_Op_Elmt);
end loop;
end if;
Next_Elmt (Iface_Elmt);
end loop Search;
end if;
-- Do not generate the wrapper if no interface primitive is covered by
-- the subprogram and it is not a primitive declared between two views
-- (see Process_Full_View).
if No (First_Param)
and then not Is_Private_Primitive_Subprogram (Subp_Id)
then
return Empty;
end if;
declare
Wrapper_Id : constant Entity_Id :=
Make_Defining_Identifier (Loc, Chars (Subp_Id));
New_Formals : List_Id;
Obj_Param : Node_Id;
Obj_Param_Typ : Entity_Id;
begin
-- Minimum decoration is needed to catch the entity in
-- Sem_Ch6.Override_Dispatching_Operation.
if Ekind (Subp_Id) = E_Function then
Mutate_Ekind (Wrapper_Id, E_Function);
else
Mutate_Ekind (Wrapper_Id, E_Procedure);
end if;
Set_Is_Primitive_Wrapper (Wrapper_Id);
Set_Wrapped_Entity (Wrapper_Id, Subp_Id);
Set_Is_Private_Primitive (Wrapper_Id,
Is_Private_Primitive_Subprogram (Subp_Id));
-- Process the formals
New_Formals := Replicate_Formals (Loc, Formals);
-- A function with a controlling result and no first controlling
-- formal needs no additional parameter.
if Has_Controlling_Result (Subp_Id)
and then
(No (First_Formal (Subp_Id))
or else not Is_Controlling_Formal (First_Formal (Subp_Id)))
then
null;
-- Routine Subp_Id has been found to override an interface primitive.
-- If the interface operation has an access parameter, create a copy
-- of it, with the same null exclusion indicator if present.
elsif Present (First_Param) then
if Nkind (Parameter_Type (First_Param)) = N_Access_Definition then
Obj_Param_Typ :=
Make_Access_Definition (Loc,
Subtype_Mark =>
New_Occurrence_Of (Obj_Typ, Loc),
Null_Exclusion_Present =>
Null_Exclusion_Present (Parameter_Type (First_Param)),
Constant_Present =>
Constant_Present (Parameter_Type (First_Param)));
else
Obj_Param_Typ := New_Occurrence_Of (Obj_Typ, Loc);
end if;
Obj_Param :=
Make_Parameter_Specification (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc,
Chars => Name_uO),
In_Present => In_Present (First_Param),
Out_Present => Out_Present (First_Param),
Parameter_Type => Obj_Param_Typ);
Prepend_To (New_Formals, Obj_Param);
-- If we are dealing with a primitive declared between two views,
-- implemented by a synchronized operation, we need to create
-- a default parameter. The mode of the parameter must match that
-- of the primitive operation.
else
pragma Assert (Is_Private_Primitive_Subprogram (Subp_Id));
Obj_Param :=
Make_Parameter_Specification (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uO),
In_Present =>
In_Present (Parent (First_Entity (Subp_Id))),
Out_Present => Ekind (Subp_Id) /= E_Function,
Parameter_Type => New_Occurrence_Of (Obj_Typ, Loc));
Prepend_To (New_Formals, Obj_Param);
end if;
-- Build the final spec. If it is a function with a controlling
-- result, it is a primitive operation of the corresponding
-- record type, so mark the spec accordingly.
if Ekind (Subp_Id) = E_Function then
declare
Res_Def : Node_Id;
begin
if Has_Controlling_Result (Subp_Id) then
Res_Def :=
New_Occurrence_Of
(Corresponding_Record_Type (Etype (Subp_Id)), Loc);
else
Res_Def := New_Copy (Result_Definition (Parent (Subp_Id)));
end if;
return
Make_Function_Specification (Loc,
Defining_Unit_Name => Wrapper_Id,
Parameter_Specifications => New_Formals,
Result_Definition => Res_Def);
end;
else
return
Make_Procedure_Specification (Loc,
Defining_Unit_Name => Wrapper_Id,
Parameter_Specifications => New_Formals);
end if;
end;
end Build_Wrapper_Spec;
-------------------------
-- Build_Wrapper_Specs --
-------------------------
procedure Build_Wrapper_Specs
(Loc : Source_Ptr;
Typ : Entity_Id;
N : in out Node_Id)
is
Def : Node_Id;
Rec_Typ : Entity_Id;
procedure Scan_Declarations (L : List_Id);
-- Common processing for visible and private declarations
-- of a protected type.
procedure Scan_Declarations (L : List_Id) is
Decl : Node_Id;
Wrap_Decl : Node_Id;
Wrap_Spec : Node_Id;
begin
if No (L) then
return;
end if;
Decl := First (L);
while Present (Decl) loop
Wrap_Spec := Empty;
if Nkind (Decl) = N_Entry_Declaration
and then Ekind (Defining_Identifier (Decl)) = E_Entry
then
Wrap_Spec :=
Build_Wrapper_Spec
(Subp_Id => Defining_Identifier (Decl),
Obj_Typ => Rec_Typ,
Formals => Parameter_Specifications (Decl));
elsif Nkind (Decl) = N_Subprogram_Declaration then
Wrap_Spec :=
Build_Wrapper_Spec
(Subp_Id => Defining_Unit_Name (Specification (Decl)),
Obj_Typ => Rec_Typ,
Formals =>
Parameter_Specifications (Specification (Decl)));
end if;
if Present (Wrap_Spec) then
Wrap_Decl :=
Make_Subprogram_Declaration (Loc,
Specification => Wrap_Spec);
Insert_After (N, Wrap_Decl);
N := Wrap_Decl;
Analyze (Wrap_Decl);
end if;
Next (Decl);
end loop;
end Scan_Declarations;
-- start of processing for Build_Wrapper_Specs
begin
if Is_Protected_Type (Typ) then
Def := Protected_Definition (Parent (Typ));
else pragma Assert (Is_Task_Type (Typ));
Def := Task_Definition (Parent (Typ));
end if;
Rec_Typ := Corresponding_Record_Type (Typ);
-- Generate wrapper specs for a concurrent type which implements an
-- interface. Operations in both the visible and private parts may
-- implement progenitor operations.
if Present (Interfaces (Rec_Typ)) and then Present (Def) then
Scan_Declarations (Visible_Declarations (Def));
Scan_Declarations (Private_Declarations (Def));
end if;
end Build_Wrapper_Specs;
---------------------------
-- Build_Find_Body_Index --
---------------------------
function Build_Find_Body_Index (Typ : Entity_Id) return Node_Id is
Loc : constant Source_Ptr := Sloc (Typ);
Ent : Entity_Id;
E_Typ : Entity_Id;
Has_F : Boolean := False;
Index : Nat;
If_St : Node_Id := Empty;
Lo : Node_Id;
Hi : Node_Id;
Decls : List_Id := New_List;
Ret : Node_Id := Empty;
Spec : Node_Id;
Siz : Node_Id := Empty;
procedure Add_If_Clause (Expr : Node_Id);
-- Add test for range of current entry
function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id;
-- If a bound of an entry is given by a discriminant, retrieve the
-- actual value of the discriminant from the enclosing object.
-------------------
-- Add_If_Clause --
-------------------
procedure Add_If_Clause (Expr : Node_Id) is
Cond : Node_Id;
Stats : constant List_Id :=
New_List (
Make_Simple_Return_Statement (Loc,
Expression => Make_Integer_Literal (Loc, Index + 1)));
begin
-- Index for current entry body
Index := Index + 1;
-- Compute total length of entry queues so far
if No (Siz) then
Siz := Expr;
else
Siz :=
Make_Op_Add (Loc,
Left_Opnd => Siz,
Right_Opnd => Expr);
end if;
Cond :=
Make_Op_Le (Loc,
Left_Opnd => Make_Identifier (Loc, Name_uE),
Right_Opnd => Siz);
-- Map entry queue indexes in the range of the current family
-- into the current index, that designates the entry body.
if No (If_St) then
If_St :=
Make_Implicit_If_Statement (Typ,
Condition => Cond,
Then_Statements => Stats,
Elsif_Parts => New_List);
Ret := If_St;
else
Append_To (Elsif_Parts (If_St),
Make_Elsif_Part (Loc,
Condition => Cond,
Then_Statements => Stats));
end if;
end Add_If_Clause;
------------------------------
-- Convert_Discriminant_Ref --
------------------------------
function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id is
B : Node_Id;
begin
if Is_Entity_Name (Bound)
and then Ekind (Entity (Bound)) = E_Discriminant
then
B :=
Make_Selected_Component (Loc,
Prefix =>
Unchecked_Convert_To (Corresponding_Record_Type (Typ),
Make_Explicit_Dereference (Loc,
Make_Identifier (Loc, Name_uObject))),
Selector_Name => Make_Identifier (Loc, Chars (Bound)));
Set_Etype (B, Etype (Entity (Bound)));
else
B := New_Copy_Tree (Bound);
end if;
return B;
end Convert_Discriminant_Ref;
-- Start of processing for Build_Find_Body_Index
begin
Spec := Build_Find_Body_Index_Spec (Typ);
Ent := First_Entity (Typ);
while Present (Ent) loop
if Ekind (Ent) = E_Entry_Family then
Has_F := True;
exit;
end if;
Next_Entity (Ent);
end loop;
if not Has_F then
-- If the protected type has no entry families, there is a one-one
-- correspondence between entry queue and entry body.
Ret :=
Make_Simple_Return_Statement (Loc,
Expression => Make_Identifier (Loc, Name_uE));
else
-- Suppose entries e1, e2, ... have size l1, l2, ... we generate
-- the following:
-- if E <= l1 then return 1;
-- elsif E <= l1 + l2 then return 2;
-- ...
Index := 0;
Siz := Empty;
Ent := First_Entity (Typ);
Add_Object_Pointer (Loc, Typ, Decls);
while Present (Ent) loop
if Ekind (Ent) = E_Entry then
Add_If_Clause (Make_Integer_Literal (Loc, 1));
elsif Ekind (Ent) = E_Entry_Family then
E_Typ := Entry_Index_Type (Ent);
Hi := Convert_Discriminant_Ref (Type_High_Bound (E_Typ));
Lo := Convert_Discriminant_Ref (Type_Low_Bound (E_Typ));
Add_If_Clause (Family_Size (Loc, Hi, Lo, Typ, False));
end if;
Next_Entity (Ent);
end loop;
if Index = 1 then
Decls := New_List;
Ret :=
Make_Simple_Return_Statement (Loc,
Expression => Make_Integer_Literal (Loc, 1));
else
pragma Assert (Present (Ret));
if Nkind (Ret) = N_If_Statement then
-- Ranges are in increasing order, so last one doesn't need
-- guard.
declare
Nod : constant Node_Id := Last (Elsif_Parts (Ret));
begin
Remove (Nod);
Set_Else_Statements (Ret, Then_Statements (Nod));
end;
end if;
end if;
end if;
return
Make_Subprogram_Body (Loc,
Specification => Spec,
Declarations => Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (Ret)));
end Build_Find_Body_Index;
--------------------------------
-- Build_Find_Body_Index_Spec --
--------------------------------
function Build_Find_Body_Index_Spec (Typ : Entity_Id) return Node_Id is
Loc : constant Source_Ptr := Sloc (Typ);
Id : constant Entity_Id :=
Make_Defining_Identifier (Loc,
Chars => New_External_Name (Chars (Typ), 'F'));
Parm1 : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uO);
Parm2 : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uE);
begin
return
Make_Function_Specification (Loc,
Defining_Unit_Name => Id,
Parameter_Specifications => New_List (
Make_Parameter_Specification (Loc,
Defining_Identifier => Parm1,
Parameter_Type =>
New_Occurrence_Of (RTE (RE_Address), Loc)),
Make_Parameter_Specification (Loc,
Defining_Identifier => Parm2,
Parameter_Type =>
New_Occurrence_Of (RTE (RE_Protected_Entry_Index), Loc))),
Result_Definition => New_Occurrence_Of (
RTE (RE_Protected_Entry_Index), Loc));
end Build_Find_Body_Index_Spec;
-----------------------------------------------
-- Build_Lock_Free_Protected_Subprogram_Body --
-----------------------------------------------
function Build_Lock_Free_Protected_Subprogram_Body
(N : Node_Id;
Prot_Typ : Node_Id;
Unprot_Spec : Node_Id) return Node_Id
is
Actuals : constant List_Id := New_List;
Loc : constant Source_Ptr := Sloc (N);
Spec : constant Node_Id := Specification (N);
Unprot_Id : constant Entity_Id := Defining_Unit_Name (Unprot_Spec);
Formal : Node_Id;
Prot_Spec : Node_Id;
Stmt : Node_Id;
begin
-- Create the protected version of the body
Prot_Spec :=
Build_Protected_Sub_Specification (N, Prot_Typ, Protected_Mode);
-- Build the actual parameters which appear in the call to the
-- unprotected version of the body.
Formal := First (Parameter_Specifications (Prot_Spec));
while Present (Formal) loop
Append_To (Actuals,
Make_Identifier (Loc, Chars (Defining_Identifier (Formal))));
Next (Formal);
end loop;
-- Function case, generate:
-- return <Unprot_Func_Call>;
if Nkind (Spec) = N_Function_Specification then
Stmt :=
Make_Simple_Return_Statement (Loc,
Expression =>
Make_Function_Call (Loc,
Name =>
Make_Identifier (Loc, Chars (Unprot_Id)),
Parameter_Associations => Actuals));
-- Procedure case, call the unprotected version
else
Stmt :=
Make_Procedure_Call_Statement (Loc,
Name =>
Make_Identifier (Loc, Chars (Unprot_Id)),
Parameter_Associations => Actuals);
end if;
return
Make_Subprogram_Body (Loc,
Declarations => Empty_List,
Specification => Prot_Spec,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (Stmt)));
end Build_Lock_Free_Protected_Subprogram_Body;
-------------------------------------------------
-- Build_Lock_Free_Unprotected_Subprogram_Body --
-------------------------------------------------
-- Procedures which meet the lock-free implementation requirements and
-- reference a unique scalar component Comp are expanded in the following
-- manner:
-- procedure P (...) is
-- Expected_Comp : constant Comp_Type :=
-- Comp_Type
-- (System.Atomic_Primitives.Lock_Free_Read_N
-- (_Object.Comp'Address));
-- begin
-- loop
-- declare
-- <original declarations before the object renaming declaration
-- of Comp>
--
-- Desired_Comp : Comp_Type := Expected_Comp;
-- Comp : Comp_Type renames Desired_Comp;
--
-- <original delarations after the object renaming declaration
-- of Comp>
--
-- begin
-- <original statements>
-- exit when System.Atomic_Primitives.Lock_Free_Try_Write_N
-- (_Object.Comp'Address,
-- Interfaces.Unsigned_N (Expected_Comp),
-- Interfaces.Unsigned_N (Desired_Comp));
-- end;
-- end loop;
-- end P;
-- Each return and raise statement of P is transformed into an atomic
-- status check:
-- if System.Atomic_Primitives.Lock_Free_Try_Write_N
-- (_Object.Comp'Address,
-- Interfaces.Unsigned_N (Expected_Comp),
-- Interfaces.Unsigned_N (Desired_Comp));
-- then
-- <original statement>
-- else
-- goto L0;
-- end if;
-- Functions which meet the lock-free implementation requirements and
-- reference a unique scalar component Comp are expanded in the following
-- manner:
-- function F (...) return ... is
-- <original declarations before the object renaming declaration
-- of Comp>
--
-- Expected_Comp : constant Comp_Type :=
-- Comp_Type
-- (System.Atomic_Primitives.Lock_Free_Read_N
-- (_Object.Comp'Address));
-- Comp : Comp_Type renames Expected_Comp;
--
-- <original delarations after the object renaming declaration of
-- Comp>
--
-- begin
-- <original statements>
-- end F;
function Build_Lock_Free_Unprotected_Subprogram_Body
(N : Node_Id;
Prot_Typ : Node_Id) return Node_Id
is
function Referenced_Component (N : Node_Id) return Entity_Id;
-- Subprograms which meet the lock-free implementation criteria are
-- allowed to reference only one unique component. Return the prival
-- of the said component.
--------------------------
-- Referenced_Component --
--------------------------
function Referenced_Component (N : Node_Id) return Entity_Id is
Comp : Entity_Id;
Decl : Node_Id;
Source_Comp : Entity_Id := Empty;
begin
-- Find the unique source component which N references in its
-- statements.
for Index in 1 .. Lock_Free_Subprogram_Table.Last loop
declare
Element : Lock_Free_Subprogram renames
Lock_Free_Subprogram_Table.Table (Index);
begin
if Element.Sub_Body = N then
Source_Comp := Element.Comp_Id;
exit;
end if;
end;
end loop;
if No (Source_Comp) then
return Empty;
end if;
-- Find the prival which corresponds to the source component within
-- the declarations of N.
Decl := First (Declarations (N));
while Present (Decl) loop
-- Privals appear as object renamings
if Nkind (Decl) = N_Object_Renaming_Declaration then
Comp := Defining_Identifier (Decl);
if Present (Prival_Link (Comp))
and then Prival_Link (Comp) = Source_Comp
then
return Comp;
end if;
end if;
Next (Decl);
end loop;
return Empty;
end Referenced_Component;
-- Local variables
Comp : constant Entity_Id := Referenced_Component (N);
Loc : constant Source_Ptr := Sloc (N);
Hand_Stmt_Seq : Node_Id := Handled_Statement_Sequence (N);
Decls : List_Id := Declarations (N);
-- Start of processing for Build_Lock_Free_Unprotected_Subprogram_Body
begin
-- Add renamings for the protection object, discriminals, privals, and
-- the entry index constant for use by debugger.
Debug_Private_Data_Declarations (Decls);
-- Perform the lock-free expansion when the subprogram references a
-- protected component.
if Present (Comp) then
Protected_Component_Ref : declare
Comp_Decl : constant Node_Id := Parent (Comp);
Comp_Sel_Nam : constant Node_Id := Name (Comp_Decl);
Comp_Type : constant Entity_Id := Etype (Comp);
Is_Procedure : constant Boolean :=
Ekind (Corresponding_Spec (N)) = E_Procedure;
-- Indicates if N is a protected procedure body
Block_Decls : List_Id := No_List;
Try_Write : Entity_Id;
Desired_Comp : Entity_Id;
Decl : Node_Id;
Label : Node_Id;
Label_Id : Entity_Id := Empty;
Read : Entity_Id;
Expected_Comp : Entity_Id;
Stmt : Node_Id;
Stmts : List_Id :=
New_Copy_List (Statements (Hand_Stmt_Seq));
Typ_Size : Int;
Unsigned : Entity_Id;
function Process_Node (N : Node_Id) return Traverse_Result;
-- Transform a single node if it is a return statement, a raise
-- statement or a reference to Comp.
procedure Process_Stmts (Stmts : List_Id);
-- Given a statement sequence Stmts, wrap any return or raise
-- statements in the following manner:
--
-- if System.Atomic_Primitives.Lock_Free_Try_Write_N
-- (_Object.Comp'Address,
-- Interfaces.Unsigned_N (Expected_Comp),
-- Interfaces.Unsigned_N (Desired_Comp))
-- then
-- <Stmt>;
-- else
-- goto L0;
-- end if;
------------------
-- Process_Node --
------------------
function Process_Node (N : Node_Id) return Traverse_Result is
procedure Wrap_Statement (Stmt : Node_Id);
-- Wrap an arbitrary statement inside an if statement where the
-- condition does an atomic check on the state of the object.
--------------------
-- Wrap_Statement --
--------------------
procedure Wrap_Statement (Stmt : Node_Id) is
begin
-- The first time through, create the declaration of a label
-- which is used to skip the remainder of source statements
-- if the state of the object has changed.
if No (Label_Id) then
Label_Id :=
Make_Identifier (Loc, New_External_Name ('L', 0));
Set_Entity (Label_Id,
Make_Defining_Identifier (Loc, Chars (Label_Id)));
end if;
-- Generate:
-- if System.Atomic_Primitives.Lock_Free_Try_Write_N
-- (_Object.Comp'Address,
-- Interfaces.Unsigned_N (Expected_Comp),
-- Interfaces.Unsigned_N (Desired_Comp))
-- then
-- <Stmt>;
-- else
-- goto L0;
-- end if;
Rewrite (Stmt,
Make_Implicit_If_Statement (N,
Condition =>
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (Try_Write, Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => Relocate_Node (Comp_Sel_Nam),
Attribute_Name => Name_Address),
Unchecked_Convert_To (Unsigned,
New_Occurrence_Of (Expected_Comp, Loc)),
Unchecked_Convert_To (Unsigned,
New_Occurrence_Of (Desired_Comp, Loc)))),
Then_Statements => New_List (Relocate_Node (Stmt)),
Else_Statements => New_List (
Make_Goto_Statement (Loc,
Name =>
New_Occurrence_Of (Entity (Label_Id), Loc)))));
end Wrap_Statement;
-- Start of processing for Process_Node
begin
-- Wrap each return and raise statement that appear inside a
-- procedure. Skip the last return statement which is added by
-- default since it is transformed into an exit statement.
if Is_Procedure
and then ((Nkind (N) = N_Simple_Return_Statement
and then N /= Last (Stmts))
or else Nkind (N) = N_Extended_Return_Statement
or else (Nkind (N) in
N_Raise_xxx_Error | N_Raise_Statement
and then Comes_From_Source (N)))
then
Wrap_Statement (N);
return Skip;
end if;
-- Force reanalysis
Set_Analyzed (N, False);
return OK;
end Process_Node;
procedure Process_Nodes is new Traverse_Proc (Process_Node);
-------------------
-- Process_Stmts --
-------------------
procedure Process_Stmts (Stmts : List_Id) is
Stmt : Node_Id;
begin
Stmt := First (Stmts);
while Present (Stmt) loop
Process_Nodes (Stmt);
Next (Stmt);
end loop;
end Process_Stmts;
-- Start of processing for Protected_Component_Ref
begin
-- Get the type size
if Known_Static_Esize (Comp_Type) then
Typ_Size := UI_To_Int (Esize (Comp_Type));
-- If the Esize (Object_Size) is unknown at compile time, look at
-- the RM_Size (Value_Size) since it may have been set by an
-- explicit representation clause.
elsif Known_Static_RM_Size (Comp_Type) then
Typ_Size := UI_To_Int (RM_Size (Comp_Type));
-- Should not happen since this has already been checked in
-- Allows_Lock_Free_Implementation (see Sem_Ch9).
else
raise Program_Error;
end if;
-- Retrieve all relevant atomic routines and types
case Typ_Size is
when 8 =>
Try_Write := RTE (RE_Lock_Free_Try_Write_8);
Read := RTE (RE_Lock_Free_Read_8);
Unsigned := RTE (RE_Uint8);
when 16 =>
Try_Write := RTE (RE_Lock_Free_Try_Write_16);
Read := RTE (RE_Lock_Free_Read_16);
Unsigned := RTE (RE_Uint16);
when 32 =>
Try_Write := RTE (RE_Lock_Free_Try_Write_32);
Read := RTE (RE_Lock_Free_Read_32);
Unsigned := RTE (RE_Uint32);
when 64 =>
Try_Write := RTE (RE_Lock_Free_Try_Write_64);
Read := RTE (RE_Lock_Free_Read_64);
Unsigned := RTE (RE_Uint64);
when others =>
raise Program_Error;
end case;
-- Generate:
-- Expected_Comp : constant Comp_Type :=
-- Comp_Type
-- (System.Atomic_Primitives.Lock_Free_Read_N
-- (_Object.Comp'Address));
Expected_Comp :=
Make_Defining_Identifier (Loc,
New_External_Name (Chars (Comp), Suffix => "_saved"));
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Expected_Comp,
Object_Definition => New_Occurrence_Of (Comp_Type, Loc),
Constant_Present => True,
Expression =>
Unchecked_Convert_To (Comp_Type,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Read, Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => Relocate_Node (Comp_Sel_Nam),
Attribute_Name => Name_Address)))));
-- Protected procedures
if Is_Procedure then
-- Move the original declarations inside the generated block
Block_Decls := Decls;
-- Reset the declarations list of the protected procedure to
-- contain only Decl.
Decls := New_List (Decl);
-- Generate:
-- Desired_Comp : Comp_Type := Expected_Comp;
Desired_Comp :=
Make_Defining_Identifier (Loc,
New_External_Name (Chars (Comp), Suffix => "_current"));
-- Insert the declarations of Expected_Comp and Desired_Comp in
-- the block declarations right before the renaming of the
-- protected component.
Insert_Before (Comp_Decl,
Make_Object_Declaration (Loc,
Defining_Identifier => Desired_Comp,
Object_Definition => New_Occurrence_Of (Comp_Type, Loc),
Expression =>
New_Occurrence_Of (Expected_Comp, Loc)));
-- Protected function
else
Desired_Comp := Expected_Comp;
-- Insert the declaration of Expected_Comp in the function
-- declarations right before the renaming of the protected
-- component.
Insert_Before (Comp_Decl, Decl);
end if;
-- Rewrite the protected component renaming declaration to be a
-- renaming of Desired_Comp.
-- Generate:
-- Comp : Comp_Type renames Desired_Comp;
Rewrite (Comp_Decl,
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier =>
Defining_Identifier (Comp_Decl),
Subtype_Mark =>
New_Occurrence_Of (Comp_Type, Loc),
Name =>
New_Occurrence_Of (Desired_Comp, Loc)));
-- Wrap any return or raise statements in Stmts in same the manner
-- described in Process_Stmts.
Process_Stmts (Stmts);
-- Generate:
-- exit when System.Atomic_Primitives.Lock_Free_Try_Write_N
-- (_Object.Comp'Address,
-- Interfaces.Unsigned_N (Expected_Comp),
-- Interfaces.Unsigned_N (Desired_Comp))
if Is_Procedure then
Stmt :=
Make_Exit_Statement (Loc,
Condition =>
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (Try_Write, Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => Relocate_Node (Comp_Sel_Nam),
Attribute_Name => Name_Address),
Unchecked_Convert_To (Unsigned,
New_Occurrence_Of (Expected_Comp, Loc)),
Unchecked_Convert_To (Unsigned,
New_Occurrence_Of (Desired_Comp, Loc)))));
-- Small optimization: transform the default return statement
-- of a procedure into the atomic exit statement.
if Nkind (Last (Stmts)) = N_Simple_Return_Statement then
Rewrite (Last (Stmts), Stmt);
else
Append_To (Stmts, Stmt);
end if;
end if;
-- Create the declaration of the label used to skip the rest of
-- the source statements when the object state changes.
if Present (Label_Id) then
Label := Make_Label (Loc, Label_Id);
Append_To (Decls,
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier => Entity (Label_Id),
Label_Construct => Label));
Append_To (Stmts, Label);
end if;
-- Generate:
-- loop
-- declare
-- <Decls>
-- begin
-- <Stmts>
-- end;
-- end loop;
if Is_Procedure then
Stmts :=
New_List (
Make_Loop_Statement (Loc,
Statements => New_List (
Make_Block_Statement (Loc,
Declarations => Block_Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Stmts))),
End_Label => Empty));
end if;
Hand_Stmt_Seq :=
Make_Handled_Sequence_Of_Statements (Loc, Statements => Stmts);
end Protected_Component_Ref;
end if;
-- Make an unprotected version of the subprogram for use within the same
-- object, with new name and extra parameter representing the object.
return
Make_Subprogram_Body (Loc,
Specification =>
Build_Protected_Sub_Specification (N, Prot_Typ, Unprotected_Mode),
Declarations => Decls,
Handled_Statement_Sequence => Hand_Stmt_Seq);
end Build_Lock_Free_Unprotected_Subprogram_Body;
-------------------------
-- Build_Master_Entity --
-------------------------
procedure Build_Master_Entity (Obj_Or_Typ : Entity_Id) is
Loc : constant Source_Ptr := Sloc (Obj_Or_Typ);
Context : Node_Id;
Context_Id : Entity_Id;
Decl : Node_Id;
Decls : List_Id;
Par : Node_Id;
begin
-- No action needed if the run-time has no tasking support
if Global_No_Tasking then
return;
end if;
if Is_Itype (Obj_Or_Typ) then
Par := Associated_Node_For_Itype (Obj_Or_Typ);
else
Par := Parent (Obj_Or_Typ);
end if;
-- For transient scopes check if the master entity is already defined
if Is_Type (Obj_Or_Typ)
and then Ekind (Scope (Obj_Or_Typ)) = E_Block
and then Is_Internal (Scope (Obj_Or_Typ))
then
declare
Master_Scope : constant Entity_Id :=
Find_Master_Scope (Obj_Or_Typ);
begin
if Has_Master_Entity (Master_Scope)
or else Is_Finalizer (Master_Scope)
then
return;
end if;
if Present (Current_Entity_In_Scope (Name_uMaster)) then
return;
end if;
end;
end if;
-- When creating a master for a record component which is either a task
-- or access-to-task, the enclosing record is the master scope and the
-- proper insertion point is the component list.
if Is_Record_Type (Current_Scope) then
Context := Par;
Context_Id := Current_Scope;
Decls := List_Containing (Context);
-- Default case for object declarations and access types. Note that the
-- context is updated to the nearest enclosing body, block, package, or
-- return statement.
else
Find_Enclosing_Context (Par, Context, Context_Id, Decls);
end if;
-- Nothing to do if the context already has a master; internally built
-- finalizers don't need a master.
if Has_Master_Entity (Context_Id)
or else Is_Finalizer (Context_Id)
then
return;
end if;
Decl := Build_Master_Declaration (Loc);
-- The master is inserted at the start of the declarative list of the
-- context.
Prepend_To (Decls, Decl);
-- In certain cases where transient scopes are involved, the immediate
-- scope is not always the proper master scope. Ensure that the master
-- declaration and entity appear in the same context.
if Context_Id /= Current_Scope then
Push_Scope (Context_Id);
Analyze (Decl);
Pop_Scope;
else
Analyze (Decl);
end if;
-- Mark the enclosing scope and its associated construct as being task
-- masters.
Set_Has_Master_Entity (Context_Id);
while Present (Context)
and then Nkind (Context) /= N_Compilation_Unit
loop
if Nkind (Context) in
N_Block_Statement | N_Subprogram_Body | N_Task_Body
then
Set_Is_Task_Master (Context);
exit;
elsif Nkind (Parent (Context)) = N_Subunit then
Context := Corresponding_Stub (Parent (Context));
end if;
Context := Parent (Context);
end loop;
end Build_Master_Entity;
---------------------------
-- Build_Master_Renaming --
---------------------------
procedure Build_Master_Renaming
(Ptr_Typ : Entity_Id;
Ins_Nod : Node_Id := Empty)
is
Loc : constant Source_Ptr := Sloc (Ptr_Typ);
Context : Node_Id;
Master_Decl : Node_Id;
Master_Id : Entity_Id;
begin
-- No action needed if the run-time has no tasking support
if Global_No_Tasking then
return;
end if;
-- Determine the proper context to insert the master renaming
if Present (Ins_Nod) then
Context := Ins_Nod;
elsif Is_Itype (Ptr_Typ) then
Context := Associated_Node_For_Itype (Ptr_Typ);
-- When the context references a discriminant or a component of a
-- private type and we are processing declarations in the private
-- part of the enclosing package, we must insert the master renaming
-- before the full declaration of the private type; otherwise the
-- master renaming would be inserted in the public part of the
-- package (and hence before the declaration of _master).
if In_Private_Part (Current_Scope) then
declare
Ctx : Node_Id := Context;
begin
if Nkind (Context) = N_Discriminant_Specification then
Ctx := Parent (Ctx);
else
while Nkind (Ctx) in
N_Component_Declaration | N_Component_List
loop
Ctx := Parent (Ctx);
end loop;
end if;
if Nkind (Ctx) in N_Private_Type_Declaration
| N_Private_Extension_Declaration
then
Context := Parent (Full_View (Defining_Identifier (Ctx)));
end if;
end;
end if;
else
Context := Parent (Ptr_Typ);
end if;
-- Generate:
-- <Ptr_Typ>M : Master_Id renames _Master;
-- and add a numeric suffix to the name to ensure that it is
-- unique in case other access types in nested constructs
-- are homonyms of this one.
Master_Id :=
Make_Defining_Identifier (Loc,
New_External_Name (Chars (Ptr_Typ), 'M', -1));
Master_Decl :=
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier => Master_Id,
Subtype_Mark =>
New_Occurrence_Of (Standard_Integer, Loc),
Name => Make_Identifier (Loc, Name_uMaster));
Insert_Action (Context, Master_Decl);
-- The renamed master now services the access type
Set_Master_Id (Ptr_Typ, Master_Id);
end Build_Master_Renaming;
---------------------------
-- Build_Protected_Entry --
---------------------------
function Build_Protected_Entry
(N : Node_Id;
Ent : Entity_Id;
Pid : Node_Id) return Node_Id
is
Bod_Decls : constant List_Id := New_List;
Decls : constant List_Id := Declarations (N);
End_Lab : constant Node_Id :=
End_Label (Handled_Statement_Sequence (N));
End_Loc : constant Source_Ptr :=
Sloc (Last (Statements (Handled_Statement_Sequence (N))));
-- Used for the generated call to Complete_Entry_Body
Loc : constant Source_Ptr := Sloc (N);
Bod_Id : Entity_Id;
Bod_Spec : Node_Id;
Bod_Stmts : List_Id;
Complete : Node_Id;
Ohandle : Node_Id;
Proc_Body : Node_Id;
EH_Loc : Source_Ptr;
-- Used for the exception handler, inserted at end of the body
begin
-- Set the source location on the exception handler only when debugging
-- the expanded code (see Make_Implicit_Exception_Handler).
if Debug_Generated_Code then
EH_Loc := End_Loc;
-- Otherwise the inserted code should not be visible to the debugger
else
EH_Loc := No_Location;
end if;
Bod_Id :=
Make_Defining_Identifier (Loc,
Chars => Chars (Protected_Body_Subprogram (Ent)));
Bod_Spec := Build_Protected_Entry_Specification (Loc, Bod_Id, Empty);
-- Add the following declarations:
-- type poVP is access poV;
-- _object : poVP := poVP (_O);
-- where _O is the formal parameter associated with the concurrent
-- object. These declarations are needed for Complete_Entry_Body.
Add_Object_Pointer (Loc, Pid, Bod_Decls);
-- Add renamings for all formals, the Protection object, discriminals,
-- privals and the entry index constant for use by debugger.
Add_Formal_Renamings (Bod_Spec, Bod_Decls, Ent, Loc);
Debug_Private_Data_Declarations (Decls);
-- Put the declarations and the statements from the entry
Bod_Stmts :=
New_List (
Make_Block_Statement (Loc,
Declarations => Decls,
Handled_Statement_Sequence => Handled_Statement_Sequence (N)));
-- Analyze now and reset scopes for declarations so that Scope fields
-- currently denoting the entry will now denote the block scope, and
-- the block's scope will be set to the new procedure entity.
Analyze_Statements (Bod_Stmts);
Set_Scope (Entity (Identifier (First (Bod_Stmts))), Bod_Id);
Reset_Scopes_To
(First (Bod_Stmts), Entity (Identifier (First (Bod_Stmts))));
case Corresponding_Runtime_Package (Pid) is
when System_Tasking_Protected_Objects_Entries =>
Append_To (Bod_Stmts,
Make_Procedure_Call_Statement (End_Loc,
Name =>
New_Occurrence_Of (RTE (RE_Complete_Entry_Body), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (End_Loc,
Prefix =>
Make_Selected_Component (End_Loc,
Prefix =>
Make_Identifier (End_Loc, Name_uObject),
Selector_Name =>
Make_Identifier (End_Loc, Name_uObject)),
Attribute_Name => Name_Unchecked_Access))));
when System_Tasking_Protected_Objects_Single_Entry =>
-- Historically, a call to Complete_Single_Entry_Body was
-- inserted, but it was a null procedure.
null;
when others =>
raise Program_Error;
end case;
-- When exceptions cannot be propagated, we never need to call
-- Exception_Complete_Entry_Body.
if No_Exception_Handlers_Set then
return
Make_Subprogram_Body (Loc,
Specification => Bod_Spec,
Declarations => Bod_Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Bod_Stmts,
End_Label => End_Lab));
else
Ohandle := Make_Others_Choice (Loc);
Set_All_Others (Ohandle);
case Corresponding_Runtime_Package (Pid) is
when System_Tasking_Protected_Objects_Entries =>
Complete :=
New_Occurrence_Of
(RTE (RE_Exceptional_Complete_Entry_Body), Loc);
when System_Tasking_Protected_Objects_Single_Entry =>
Complete :=
New_Occurrence_Of
(RTE (RE_Exceptional_Complete_Single_Entry_Body), Loc);
when others =>
raise Program_Error;
end case;
-- Create body of entry procedure. The renaming declarations are
-- placed ahead of the block that contains the actual entry body.
Proc_Body :=
Make_Subprogram_Body (Loc,
Specification => Bod_Spec,
Declarations => Bod_Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Bod_Stmts,
End_Label => End_Lab,
Exception_Handlers => New_List (
Make_Implicit_Exception_Handler (EH_Loc,
Exception_Choices => New_List (Ohandle),
Statements => New_List (
Make_Procedure_Call_Statement (EH_Loc,
Name => Complete,
Parameter_Associations => New_List (
Make_Attribute_Reference (EH_Loc,
Prefix =>
Make_Selected_Component (EH_Loc,
Prefix =>
Make_Identifier (EH_Loc, Name_uObject),
Selector_Name =>
Make_Identifier (EH_Loc, Name_uObject)),
Attribute_Name => Name_Unchecked_Access),
Make_Function_Call (EH_Loc,
Name =>
New_Occurrence_Of
(RTE (RE_Get_GNAT_Exception), Loc)))))))));
-- Establish link between subprogram body and source entry body
Set_Corresponding_Entry_Body (Proc_Body, N);
Reset_Scopes_To (Proc_Body, Protected_Body_Subprogram (Ent));
return Proc_Body;
end if;
end Build_Protected_Entry;
-----------------------------------------
-- Build_Protected_Entry_Specification --
-----------------------------------------
function Build_Protected_Entry_Specification
(Loc : Source_Ptr;
Def_Id : Entity_Id;
Ent_Id : Entity_Id) return Node_Id
is
P : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uP);
begin
Set_Debug_Info_Needed (Def_Id);
if Present (Ent_Id) then
Append_Elmt (P, Accept_Address (Ent_Id));
end if;
return
Make_Procedure_Specification (Loc,
Defining_Unit_Name => Def_Id,
Parameter_Specifications => New_List (
Make_Parameter_Specification (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uO),
Parameter_Type =>
New_Occurrence_Of (RTE (RE_Address), Loc)),
Make_Parameter_Specification (Loc,
Defining_Identifier => P,
Parameter_Type =>
New_Occurrence_Of (RTE (RE_Address), Loc)),
Make_Parameter_Specification (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uE),
Parameter_Type =>
New_Occurrence_Of (RTE (RE_Protected_Entry_Index), Loc))));
end Build_Protected_Entry_Specification;
--------------------------
-- Build_Protected_Spec --
--------------------------
function Build_Protected_Spec
(N : Node_Id;
Obj_Type : Entity_Id;
Ident : Entity_Id;
Unprotected : Boolean := False) return List_Id
is
Loc : constant Source_Ptr := Sloc (N);
Decl : Node_Id;
Formal : Entity_Id;
New_Plist : List_Id;
New_Param : Node_Id;
begin
New_Plist := New_List;
Formal := First_Formal (Ident);
while Present (Formal) loop
New_Param :=
Make_Parameter_Specification (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Sloc (Formal), Chars (Formal)),
Aliased_Present => Aliased_Present (Parent (Formal)),
In_Present => In_Present (Parent (Formal)),
Out_Present => Out_Present (Parent (Formal)),
Parameter_Type => New_Occurrence_Of (Etype (Formal), Loc));
if Unprotected then
Set_Protected_Formal (Formal, Defining_Identifier (New_Param));
Mutate_Ekind (Defining_Identifier (New_Param), Ekind (Formal));
end if;
Append (New_Param, New_Plist);
Next_Formal (Formal);
end loop;
-- If the subprogram is a procedure and the context is not an access
-- to protected subprogram, the parameter is in-out. Otherwise it is
-- an in parameter.
Decl :=
Make_Parameter_Specification (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uObject),
In_Present => True,
Out_Present =>
(Etype (Ident) = Standard_Void_Type
and then not Is_RTE (Obj_Type, RE_Address)),
Parameter_Type =>
New_Occurrence_Of (Obj_Type, Loc));
Set_Debug_Info_Needed (Defining_Identifier (Decl));
Prepend_To (New_Plist, Decl);
return New_Plist;
end Build_Protected_Spec;
---------------------------------------
-- Build_Protected_Sub_Specification --
---------------------------------------
function Build_Protected_Sub_Specification
(N : Node_Id;
Prot_Typ : Entity_Id;
Mode : Subprogram_Protection_Mode) return Node_Id
is
Loc : constant Source_Ptr := Sloc (N);
Decl : Node_Id;
Def_Id : Entity_Id;
New_Id : Entity_Id;
New_Plist : List_Id;
New_Spec : Node_Id;
Append_Chr : constant array (Subprogram_Protection_Mode) of Character :=
(Dispatching_Mode => ' ',
Protected_Mode => 'P',
Unprotected_Mode => 'N');
begin
if Ekind (Defining_Unit_Name (Specification (N))) = E_Subprogram_Body
then
Decl := Unit_Declaration_Node (Corresponding_Spec (N));
else
Decl := N;
end if;
Def_Id := Defining_Unit_Name (Specification (Decl));
New_Plist :=
Build_Protected_Spec
(Decl, Corresponding_Record_Type (Prot_Typ), Def_Id,
Mode = Unprotected_Mode);
New_Id :=
Make_Defining_Identifier (Loc,
Chars => Build_Selected_Name (Prot_Typ, Def_Id, Append_Chr (Mode)));
-- Reference the original nondispatching subprogram since the analysis
-- of the object.operation notation may need its original name (see
-- Sem_Ch4.Names_Match).
if Mode = Dispatching_Mode then
Mutate_Ekind (New_Id, Ekind (Def_Id));
Set_Original_Protected_Subprogram (New_Id, Def_Id);
end if;
-- Link the protected or unprotected version to the original subprogram
-- it emulates.
Mutate_Ekind (New_Id, Ekind (Def_Id));
Set_Protected_Subprogram (New_Id, Def_Id);
-- The unprotected operation carries the user code, and debugging
-- information must be generated for it, even though this spec does
-- not come from source. It is also convenient to allow gdb to step
-- into the protected operation, even though it only contains lock/
-- unlock calls.
Set_Debug_Info_Needed (New_Id);
-- If a pragma Eliminate applies to the source entity, the internal
-- subprograms will be eliminated as well.
Set_Is_Eliminated (New_Id, Is_Eliminated (Def_Id));
-- It seems we should set Has_Nested_Subprogram here, but instead we
-- currently set it in Expand_N_Protected_Body, because the entity
-- created here isn't the one that Corresponding_Spec of the body
-- will later be set to, and that's the entity where it's needed. ???
Set_Has_Nested_Subprogram (New_Id, Has_Nested_Subprogram (Def_Id));
if Nkind (Specification (Decl)) = N_Procedure_Specification then
New_Spec :=
Make_Procedure_Specification (Loc,
Defining_Unit_Name => New_Id,
Parameter_Specifications => New_Plist);
-- Create a new specification for the anonymous subprogram type
else
New_Spec :=
Make_Function_Specification (Loc,
Defining_Unit_Name => New_Id,
Parameter_Specifications => New_Plist,
Result_Definition =>
Copy_Result_Type (Result_Definition (Specification (Decl))));
Set_Return_Present (Defining_Unit_Name (New_Spec));
end if;
return New_Spec;
end Build_Protected_Sub_Specification;
-------------------------------------
-- Build_Protected_Subprogram_Body --
-------------------------------------
function Build_Protected_Subprogram_Body
(N : Node_Id;
Pid : Node_Id;
N_Op_Spec : Node_Id) return Node_Id
is
Exc_Safe : constant Boolean := not Might_Raise (N);
-- True if N cannot raise an exception
Loc : constant Source_Ptr := Sloc (N);
Op_Spec : constant Node_Id := Specification (N);
P_Op_Spec : constant Node_Id :=
Build_Protected_Sub_Specification (N, Pid, Protected_Mode);
Lock_Kind : RE_Id;
Lock_Name : Node_Id;
Lock_Stmt : Node_Id;
Object_Parm : Node_Id;
Pformal : Node_Id;
R : Node_Id;
Return_Stmt : Node_Id := Empty; -- init to avoid gcc 3 warning
Pre_Stmts : List_Id := No_List; -- init to avoid gcc 3 warning
Stmts : List_Id;
Sub_Body : Node_Id;
Uactuals : List_Id;
Unprot_Call : Node_Id;
begin
-- Build a list of the formal parameters of the protected version of
-- the subprogram to use as the actual parameters of the unprotected
-- version.
Uactuals := New_List;
Pformal := First (Parameter_Specifications (P_Op_Spec));
while Present (Pformal) loop
Append_To (Uactuals,
Make_Identifier (Loc, Chars (Defining_Identifier (Pformal))));
Next (Pformal);
end loop;
-- Make a call to the unprotected version of the subprogram built above
-- for use by the protected version built below.
if Nkind (Op_Spec) = N_Function_Specification then
if Exc_Safe then
R := Make_Temporary (Loc, 'R');
Unprot_Call :=
Make_Object_Declaration (Loc,
Defining_Identifier => R,
Constant_Present => True,
Object_Definition =>
New_Copy (Result_Definition (N_Op_Spec)),
Expression =>
Make_Function_Call (Loc,
Name =>
Make_Identifier (Loc,
Chars => Chars (Defining_Unit_Name (N_Op_Spec))),
Parameter_Associations => Uactuals));
Return_Stmt :=
Make_Simple_Return_Statement (Loc,
Expression => New_Occurrence_Of (R, Loc));
else
Unprot_Call :=
Make_Simple_Return_Statement (Loc,
Expression =>
Make_Function_Call (Loc,
Name =>
Make_Identifier (Loc,
Chars => Chars (Defining_Unit_Name (N_Op_Spec))),
Parameter_Associations => Uactuals));
end if;
if Has_Aspect (Pid, Aspect_Exclusive_Functions)
and then
(No (Find_Value_Of_Aspect (Pid, Aspect_Exclusive_Functions))
or else
Is_True (Static_Boolean (Find_Value_Of_Aspect
(Pid, Aspect_Exclusive_Functions))))
then
Lock_Kind := RE_Lock;
else
Lock_Kind := RE_Lock_Read_Only;
end if;
else
Unprot_Call :=
Make_Procedure_Call_Statement (Loc,
Name =>
Make_Identifier (Loc, Chars (Defining_Unit_Name (N_Op_Spec))),
Parameter_Associations => Uactuals);
Lock_Kind := RE_Lock;
end if;
-- Wrap call in block that will be covered by an at_end handler
if not Exc_Safe then
Unprot_Call :=
Make_Block_Statement (Loc,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (Unprot_Call)));
end if;
-- Make the protected subprogram body. This locks the protected
-- object and calls the unprotected version of the subprogram.
case Corresponding_Runtime_Package (Pid) is
when System_Tasking_Protected_Objects_Entries =>
Lock_Name := New_Occurrence_Of (RTE (RE_Lock_Entries), Loc);
when System_Tasking_Protected_Objects_Single_Entry =>
Lock_Name := New_Occurrence_Of (RTE (RE_Lock_Entry), Loc);
when System_Tasking_Protected_Objects =>
Lock_Name := New_Occurrence_Of (RTE (Lock_Kind), Loc);
when others =>
raise Program_Error;
end case;
Object_Parm :=
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uObject),
Selector_Name => Make_Identifier (Loc, Name_uObject)),
Attribute_Name => Name_Unchecked_Access);
Lock_Stmt :=
Make_Procedure_Call_Statement (Loc,
Name => Lock_Name,
Parameter_Associations => New_List (Object_Parm));
if Abort_Allowed then
Stmts := New_List (
Build_Runtime_Call (Loc, RE_Abort_Defer),
Lock_Stmt);
else
Stmts := New_List (Lock_Stmt);
end if;
if not Exc_Safe then
Append (Unprot_Call, Stmts);
else
if Nkind (Op_Spec) = N_Function_Specification then
Pre_Stmts := Stmts;
Stmts := Empty_List;
else
Append (Unprot_Call, Stmts);
end if;
-- Historical note: Previously, call to the cleanup was inserted
-- here. This is now done by Build_Protected_Subprogram_Call_Cleanup,
-- which is also shared by the 'not Exc_Safe' path.
Build_Protected_Subprogram_Call_Cleanup (Op_Spec, Pid, Loc, Stmts);
if Nkind (Op_Spec) = N_Function_Specification then
Append_To (Stmts, Return_Stmt);
Append_To (Pre_Stmts,
Make_Block_Statement (Loc,
Declarations => New_List (Unprot_Call),
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Stmts)));
Stmts := Pre_Stmts;
end if;
end if;
Sub_Body :=
Make_Subprogram_Body (Loc,
Declarations => Empty_List,
Specification => P_Op_Spec,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Statements => Stmts));
-- Mark this subprogram as a protected subprogram body so that the
-- cleanup will be inserted. This is done only in the 'not Exc_Safe'
-- path as otherwise the cleanup has already been inserted.
if not Exc_Safe then
Set_Is_Protected_Subprogram_Body (Sub_Body);
end if;
return Sub_Body;
end Build_Protected_Subprogram_Body;
-------------------------------------
-- Build_Protected_Subprogram_Call --
-------------------------------------
procedure Build_Protected_Subprogram_Call
(N : Node_Id;
Name : Node_Id;
Rec : Node_Id;
External : Boolean := True)
is
Loc : constant Source_Ptr := Sloc (N);
Sub : constant Entity_Id := Entity (Name);
New_Sub : Node_Id;
Params : List_Id;
begin
if External then
New_Sub := New_Occurrence_Of (External_Subprogram (Sub), Loc);
else
New_Sub :=
New_Occurrence_Of (Protected_Body_Subprogram (Sub), Loc);
end if;
if Present (Parameter_Associations (N)) then
Params := New_Copy_List_Tree (Parameter_Associations (N));
else
Params := New_List;
end if;
-- If the type is an untagged derived type, convert to the root type,
-- which is the one on which the operations are defined.
if Nkind (Rec) = N_Unchecked_Type_Conversion
and then not Is_Tagged_Type (Etype (Rec))
and then Is_Derived_Type (Etype (Rec))
then
Set_Etype (Rec, Root_Type (Etype (Rec)));
Set_Subtype_Mark (Rec,
New_Occurrence_Of (Root_Type (Etype (Rec)), Sloc (N)));
end if;
Prepend (Rec, Params);
if Ekind (Sub) = E_Procedure then
Rewrite (N,
Make_Procedure_Call_Statement (Loc,
Name => New_Sub,
Parameter_Associations => Params));
else
pragma Assert (Ekind (Sub) = E_Function);
Rewrite (N,
Make_Function_Call (Loc,
Name => New_Sub,
Parameter_Associations => Params));
-- Preserve type of call for subsequent processing (required for
-- call to Wrap_Transient_Expression in the case of a shared passive
-- protected).
Set_Etype (N, Etype (New_Sub));
end if;
if External
and then Nkind (Rec) = N_Unchecked_Type_Conversion
and then Is_Entity_Name (Expression (Rec))
and then Is_Shared_Passive (Entity (Expression (Rec)))
then
Add_Shared_Var_Lock_Procs (N);
end if;
end Build_Protected_Subprogram_Call;
---------------------------------------------
-- Build_Protected_Subprogram_Call_Cleanup --
---------------------------------------------
procedure Build_Protected_Subprogram_Call_Cleanup
(Op_Spec : Node_Id;
Conc_Typ : Node_Id;
Loc : Source_Ptr;
Stmts : List_Id)
is
Nam : Node_Id;
begin
-- If the associated protected object has entries, a protected
-- procedure has to service entry queues. In this case generate:
-- Service_Entries (_object._object'Access);
if Nkind (Op_Spec) = N_Procedure_Specification
and then Has_Entries (Conc_Typ)
then
case Corresponding_Runtime_Package (Conc_Typ) is
when System_Tasking_Protected_Objects_Entries =>
Nam := New_Occurrence_Of (RTE (RE_Service_Entries), Loc);
when System_Tasking_Protected_Objects_Single_Entry =>
Nam := New_Occurrence_Of (RTE (RE_Service_Entry), Loc);
when others =>
raise Program_Error;
end case;
Append_To (Stmts,
Make_Procedure_Call_Statement (Loc,
Name => Nam,
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uObject),
Selector_Name => Make_Identifier (Loc, Name_uObject)),
Attribute_Name => Name_Unchecked_Access))));
else
-- Generate:
-- Unlock (_object._object'Access);
case Corresponding_Runtime_Package (Conc_Typ) is
when System_Tasking_Protected_Objects_Entries =>
Nam := New_Occurrence_Of (RTE (RE_Unlock_Entries), Loc);
when System_Tasking_Protected_Objects_Single_Entry =>
Nam := New_Occurrence_Of (RTE (RE_Unlock_Entry), Loc);
when System_Tasking_Protected_Objects =>
Nam := New_Occurrence_Of (RTE (RE_Unlock), Loc);
when others =>
raise Program_Error;
end case;
Append_To (Stmts,
Make_Procedure_Call_Statement (Loc,
Name => Nam,
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uObject),
Selector_Name => Make_Identifier (Loc, Name_uObject)),
Attribute_Name => Name_Unchecked_Access))));
end if;
-- Generate:
-- Abort_Undefer;
if Abort_Allowed then
Append_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Undefer));
end if;
end Build_Protected_Subprogram_Call_Cleanup;
-------------------------
-- Build_Selected_Name --
-------------------------
function Build_Selected_Name
(Prefix : Entity_Id;
Selector : Entity_Id;
Append_Char : Character := ' ') return Name_Id
is
Select_Buffer : String (1 .. Hostparm.Max_Name_Length);
Select_Len : Natural;
begin
Get_Name_String (Chars (Selector));
Select_Len := Name_Len;
Select_Buffer (1 .. Select_Len) := Name_Buffer (1 .. Name_Len);
Get_Name_String (Chars (Prefix));
-- If scope is anonymous type, discard suffix to recover name of
-- single protected object. Otherwise use protected type name.
if Name_Buffer (Name_Len) = 'T' then
Name_Len := Name_Len - 1;
end if;
Add_Str_To_Name_Buffer ("__");
for J in 1 .. Select_Len loop
Add_Char_To_Name_Buffer (Select_Buffer (J));
end loop;
-- Now add the Append_Char if specified. The encoding to follow
-- depends on the type of entity. If Append_Char is either 'N' or 'P',
-- then the entity is associated to a protected type subprogram.
-- Otherwise, it is a protected type entry. For each case, the
-- encoding to follow for the suffix is documented in exp_dbug.ads.
-- It would be better to encapsulate this as a routine in Exp_Dbug ???
if Append_Char /= ' ' then
if Append_Char = 'P' or Append_Char = 'N' then
Add_Char_To_Name_Buffer (Append_Char);
return Name_Find;
else
Add_Str_To_Name_Buffer ((1 => '_', 2 => Append_Char));
return New_External_Name (Name_Find, ' ', -1);
end if;
else
return Name_Find;
end if;
end Build_Selected_Name;
-----------------------------
-- Build_Simple_Entry_Call --
-----------------------------
-- A task entry call is converted to a call to Call_Simple
-- declare
-- P : parms := (parm, parm, parm);
-- begin
-- Call_Simple (acceptor-task, entry-index, P'Address);
-- parm := P.param;
-- parm := P.param;
-- ...
-- end;
-- Here Pnn is an aggregate of the type constructed for the entry to hold
-- the parameters, and the constructed aggregate value contains either the
-- parameters or, in the case of non-elementary types, references to these
-- parameters. Then the address of this aggregate is passed to the runtime
-- routine, along with the task id value and the task entry index value.
-- Pnn is only required if parameters are present.
-- The assignments after the call are present only in the case of in-out
-- or out parameters for elementary types, and are used to assign back the
-- resulting values of such parameters.
-- Note: the reason that we insert a block here is that in the context
-- of selects, conditional entry calls etc. the entry call statement
-- appears on its own, not as an element of a list.
-- A protected entry call is converted to a Protected_Entry_Call:
-- declare
-- P : E1_Params := (param, param, param);
-- Pnn : Boolean;
-- Bnn : Communications_Block;
-- declare
-- P : E1_Params := (param, param, param);
-- Bnn : Communications_Block;
-- begin
-- Protected_Entry_Call (
-- Object => po._object'Access,
-- E => <entry index>;
-- Uninterpreted_Data => P'Address;
-- Mode => Simple_Call;
-- Block => Bnn);
-- parm := P.param;
-- parm := P.param;
-- ...
-- end;
procedure Build_Simple_Entry_Call
(N : Node_Id;
Concval : Node_Id;
Ename : Node_Id;
Index : Node_Id)
is
begin
Expand_Call (N);
-- If call has been inlined, nothing left to do
if Nkind (N) = N_Block_Statement then
return;
end if;
-- Convert entry call to Call_Simple call
declare
Loc : constant Source_Ptr := Sloc (N);
Parms : constant List_Id := Parameter_Associations (N);
Stats : constant List_Id := New_List;
Actual : Node_Id;
Call : Node_Id;
Comm_Name : Entity_Id;
Conctyp : Node_Id;
Decls : List_Id;
Ent : Entity_Id;
Ent_Acc : Entity_Id;
Formal : Node_Id;
Iface_Tag : Entity_Id;
Iface_Typ : Entity_Id;
N_Node : Node_Id;
N_Var : Node_Id;
P : Entity_Id;
Parm1 : Node_Id;
Parm2 : Node_Id;
Parm3 : Node_Id;
Pdecl : Node_Id;
Plist : List_Id;
X : Entity_Id;
Xdecl : Node_Id;
begin
-- Simple entry and entry family cases merge here
Ent := Entity (Ename);
Ent_Acc := Entry_Parameters_Type (Ent);
Conctyp := Etype (Concval);
-- Special case for protected subprogram calls
if Is_Protected_Type (Conctyp)
and then Is_Subprogram (Entity (Ename))
then
if not Is_Eliminated (Entity (Ename)) then
Build_Protected_Subprogram_Call
(N, Ename, Convert_Concurrent (Concval, Conctyp));
Analyze (N);
end if;
return;
end if;
-- First parameter is the Task_Id value from the task value or the
-- Object from the protected object value, obtained by selecting
-- the _Task_Id or _Object from the result of doing an unchecked
-- conversion to convert the value to the corresponding record type.
if Nkind (Concval) = N_Function_Call
and then Is_Task_Type (Conctyp)
and then Ada_Version >= Ada_2005
then
declare
ExpR : constant Node_Id := Relocate_Node (Concval);
Obj : constant Entity_Id := Make_Temporary (Loc, 'F', ExpR);
Decl : Node_Id;
begin
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Obj,
Object_Definition => New_Occurrence_Of (Conctyp, Loc),
Expression => ExpR);
Set_Etype (Obj, Conctyp);
Decls := New_List (Decl);
Rewrite (Concval, New_Occurrence_Of (Obj, Loc));
end;
else
Decls := New_List;
end if;
Parm1 := Concurrent_Ref (Concval);
-- Second parameter is the entry index, computed by the routine
-- provided for this purpose. The value of this expression is
-- assigned to an intermediate variable to assure that any entry
-- family index expressions are evaluated before the entry
-- parameters.
if not Is_Protected_Type (Conctyp)
or else
Corresponding_Runtime_Package (Conctyp) =
System_Tasking_Protected_Objects_Entries
then
X := Make_Defining_Identifier (Loc, Name_uX);
Xdecl :=
Make_Object_Declaration (Loc,
Defining_Identifier => X,
Object_Definition =>
New_Occurrence_Of (RTE (RE_Task_Entry_Index), Loc),
Expression => Actual_Index_Expression (
Loc, Entity (Ename), Index, Concval));
Append_To (Decls, Xdecl);
Parm2 := New_Occurrence_Of (X, Loc);
else
Xdecl := Empty;
Parm2 := Empty;
end if;
-- The third parameter is the packaged parameters. If there are
-- none, then it is just the null address, since nothing is passed.
if No (Parms) then
Parm3 := New_Occurrence_Of (RTE (RE_Null_Address), Loc);
P := Empty;
-- Case of parameters present, where third argument is the address
-- of a packaged record containing the required parameter values.
else
-- First build a list of parameter values, which are references to
-- objects of the parameter types.
Plist := New_List;
Actual := First_Actual (N);
Formal := First_Formal (Ent);
while Present (Actual) loop
-- If it is a by-copy type, copy it to a new variable. The
-- packaged record has a field that points to this variable.
if Is_By_Copy_Type (Etype (Actual)) then
N_Node :=
Make_Object_Declaration (Loc,
Defining_Identifier => Make_Temporary (Loc, 'J'),
Aliased_Present => True,
Object_Definition =>
New_Occurrence_Of (Etype (Formal), Loc));
-- Mark the object as not needing initialization since the
-- initialization is performed separately, avoiding errors
-- on cases such as formals of null-excluding access types.
Set_No_Initialization (N_Node);
-- We must make a separate assignment statement for the
-- case of limited types. We cannot assign it unless the
-- Assignment_OK flag is set first. An out formal of an
-- access type or whose type has a Default_Value must also
-- be initialized from the actual (see RM 6.4.1 (13-13.1)),
-- but no constraint, predicate, or null-exclusion check is
-- applied before the call.
if Ekind (Formal) /= E_Out_Parameter
or else Is_Access_Type (Etype (Formal))
or else
(Is_Scalar_Type (Etype (Formal))
and then
Present (Default_Aspect_Value (Etype (Formal))))
then
N_Var :=
New_Occurrence_Of (Defining_Identifier (N_Node), Loc);
Set_Assignment_OK (N_Var);
Append_To (Stats,
Make_Assignment_Statement (Loc,
Name => N_Var,
Expression => Relocate_Node (Actual)));
-- Mark the object as internal, so we don't later reset
-- No_Initialization flag in Default_Initialize_Object,
-- which would lead to needless default initialization.
-- We don't set this outside the if statement, because
-- out scalar parameters without Default_Value do require
-- default initialization if Initialize_Scalars applies.
Set_Is_Internal (Defining_Identifier (N_Node));
-- If actual is an out parameter of a null-excluding
-- access type, there is access check on entry, so set
-- Suppress_Assignment_Checks on the generated statement
-- that assigns the actual to the parameter block.
Set_Suppress_Assignment_Checks (Last (Stats));
end if;
Append (N_Node, Decls);
Append_To (Plist,
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Unchecked_Access,
Prefix =>
New_Occurrence_Of
(Defining_Identifier (N_Node), Loc)));
else
-- Interface class-wide formal
if Ada_Version >= Ada_2005
and then Ekind (Etype (Formal)) = E_Class_Wide_Type
and then Is_Interface (Etype (Formal))
then
Iface_Typ := Etype (Etype (Formal));
-- Generate:
-- formal_iface_type! (actual.iface_tag)'reference
Iface_Tag :=
Find_Interface_Tag (Etype (Actual), Iface_Typ);
pragma Assert (Present (Iface_Tag));
Append_To (Plist,
Make_Reference (Loc,
Unchecked_Convert_To (Iface_Typ,
Make_Selected_Component (Loc,
Prefix =>
Relocate_Node (Actual),
Selector_Name =>
New_Occurrence_Of (Iface_Tag, Loc)))));
else
-- Generate:
-- actual'reference
Append_To (Plist,
Make_Reference (Loc, Relocate_Node (Actual)));
end if;
end if;
Next_Actual (Actual);
Next_Formal_With_Extras (Formal);
end loop;
-- Now build the declaration of parameters initialized with the
-- aggregate containing this constructed parameter list.
P := Make_Defining_Identifier (Loc, Name_uP);
Pdecl :=
Make_Object_Declaration (Loc,
Defining_Identifier => P,
Object_Definition =>
New_Occurrence_Of (Designated_Type (Ent_Acc), Loc),
Expression =>
Make_Aggregate (Loc, Expressions => Plist));
Parm3 :=
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (P, Loc),
Attribute_Name => Name_Address);
Append (Pdecl, Decls);
end if;
-- Now we can create the call, case of protected type
if Is_Protected_Type (Conctyp) then
case Corresponding_Runtime_Package (Conctyp) is
when System_Tasking_Protected_Objects_Entries =>
-- Change the type of the index declaration
Set_Object_Definition (Xdecl,
New_Occurrence_Of (RTE (RE_Protected_Entry_Index), Loc));
-- Some additional declarations for protected entry calls
if No (Decls) then
Decls := New_List;
end if;
-- Bnn : Communications_Block;
Comm_Name := Make_Temporary (Loc, 'B');
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => Comm_Name,
Object_Definition =>
New_Occurrence_Of
(RTE (RE_Communication_Block), Loc)));
-- Some additional statements for protected entry calls
-- Protected_Entry_Call
-- (Object => po._object'Access,
-- E => <entry index>;
-- Uninterpreted_Data => P'Address;
-- Mode => Simple_Call;
-- Block => Bnn);
Call :=
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Protected_Entry_Call), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Unchecked_Access,
Prefix => Parm1),
Parm2,
Parm3,
New_Occurrence_Of (RTE (RE_Simple_Call), Loc),
New_Occurrence_Of (Comm_Name, Loc)));
when System_Tasking_Protected_Objects_Single_Entry =>
-- Protected_Single_Entry_Call
-- (Object => po._object'Access,
-- Uninterpreted_Data => P'Address);
Call :=
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of
(RTE (RE_Protected_Single_Entry_Call), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Unchecked_Access,
Prefix => Parm1),
Parm3));
when others =>
raise Program_Error;
end case;
-- Case of task type
else
Call :=
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Call_Simple), Loc),
Parameter_Associations => New_List (Parm1, Parm2, Parm3));
end if;
Append_To (Stats, Call);
-- If there are out or in/out parameters by copy add assignment
-- statements for the result values.
if Present (Parms) then
Actual := First_Actual (N);
Formal := First_Formal (Ent);
Set_Assignment_OK (Actual);
while Present (Actual) loop
if Is_By_Copy_Type (Etype (Actual))
and then Ekind (Formal) /= E_In_Parameter
then
N_Node :=
Make_Assignment_Statement (Loc,
Name => New_Copy (Actual),
Expression =>
Make_Explicit_Dereference (Loc,
Make_Selected_Component (Loc,
Prefix => New_Occurrence_Of (P, Loc),
Selector_Name =>
Make_Identifier (Loc, Chars (Formal)))));
-- In all cases (including limited private types) we want
-- the assignment to be valid.
Set_Assignment_OK (Name (N_Node));
-- If the call is the triggering alternative in an
-- asynchronous select, or the entry_call alternative of a
-- conditional entry call, the assignments for in-out
-- parameters are incorporated into the statement list that
-- follows, so that there are executed only if the entry
-- call succeeds.
if (Nkind (Parent (N)) = N_Triggering_Alternative
and then N = Triggering_Statement (Parent (N)))
or else
(Nkind (Parent (N)) = N_Entry_Call_Alternative
and then N = Entry_Call_Statement (Parent (N)))
then
if No (Statements (Parent (N))) then
Set_Statements (Parent (N), New_List);
end if;
Prepend (N_Node, Statements (Parent (N)));
else
Insert_After (Call, N_Node);
end if;
end if;
Next_Actual (Actual);
Next_Formal_With_Extras (Formal);
end loop;
end if;
-- Finally, create block and analyze it
Rewrite (N,
Make_Block_Statement (Loc,
Declarations => Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Stats)));
Analyze (N);
end;
end Build_Simple_Entry_Call;
--------------------------------
-- Build_Task_Activation_Call --
--------------------------------
procedure Build_Task_Activation_Call (N : Node_Id) is
function Activation_Call_Loc return Source_Ptr;
-- Find a suitable source location for the activation call
-------------------------
-- Activation_Call_Loc --
-------------------------
function Activation_Call_Loc return Source_Ptr is
begin
-- The activation call must carry the location of the "end" keyword
-- when the context is a package declaration.
if Nkind (N) = N_Package_Declaration then
return End_Keyword_Location (N);
-- Otherwise the activation call must carry the location of the
-- "begin" keyword.
else
return Begin_Keyword_Location (N);
end if;
end Activation_Call_Loc;
-- Local variables
Chain : Entity_Id;
Call : Node_Id;
Loc : Source_Ptr;
Name : Node_Id;
Owner : Node_Id;
Stmt : Node_Id;
-- Start of processing for Build_Task_Activation_Call
begin
-- For sequential elaboration policy, all the tasks will be activated at
-- the end of the elaboration.
if Partition_Elaboration_Policy = 'S' then
return;
-- Do not create an activation call for a package spec if the package
-- has a completing body. The activation call will be inserted after
-- the "begin" of the body.
elsif Nkind (N) = N_Package_Declaration
and then Present (Corresponding_Body (N))
then
return;
end if;
-- Obtain the activation chain entity. Block statements, entry bodies,
-- subprogram bodies, and task bodies keep the entity in their nodes.
-- Package bodies on the other hand store it in the declaration of the
-- corresponding package spec.
Owner := N;
if Nkind (Owner) = N_Package_Body then
Owner := Unit_Declaration_Node (Corresponding_Spec (Owner));
end if;
Chain := Activation_Chain_Entity (Owner);
-- Nothing to do when there are no tasks to activate. This is indicated
-- by a missing activation chain entity; also skip generating it when
-- it is a ghost entity.
if No (Chain) or else Is_Ignored_Ghost_Entity (Chain) then
return;
-- The availability of the activation chain entity does not ensure
-- that we have tasks to activate because it may have been declared
-- by the frontend to pass a required extra formal to a build-in-place
-- subprogram call. If we are within the scope of a protected type and
-- pragma Detect_Blocking is active we can assume that no tasks will be
-- activated; if tasks are created in a protected object and this pragma
-- is active then the frontend emits a warning and Program_Error is
-- raised at runtime.
elsif Detect_Blocking and then Within_Protected_Type (Current_Scope) then
return;
end if;
-- The location of the activation call must be as close as possible to
-- the intended semantic location of the activation because the ABE
-- mechanism relies heavily on accurate locations.
Loc := Activation_Call_Loc;
if Restricted_Profile then
Name := New_Occurrence_Of (RTE (RE_Activate_Restricted_Tasks), Loc);
else
Name := New_Occurrence_Of (RTE (RE_Activate_Tasks), Loc);
end if;
Call :=
Make_Procedure_Call_Statement (Loc,
Name => Name,
Parameter_Associations =>
New_List (Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Chain, Loc),
Attribute_Name => Name_Unchecked_Access)));
if Nkind (N) = N_Package_Declaration then
if Present (Private_Declarations (Specification (N))) then
Append (Call, Private_Declarations (Specification (N)));
else
Append (Call, Visible_Declarations (Specification (N)));
end if;
else
-- The call goes at the start of the statement sequence after the
-- start of exception range label if one is present.
if Present (Handled_Statement_Sequence (N)) then
Stmt := First (Statements (Handled_Statement_Sequence (N)));
-- A special case, skip exception range label if one is present
-- (from front end zcx processing).
if Nkind (Stmt) = N_Label and then Exception_Junk (Stmt) then
Next (Stmt);
end if;
-- Another special case, if the first statement is a block from
-- optimization of a local raise to a goto, then the call goes
-- inside this block.
if Nkind (Stmt) = N_Block_Statement
and then Exception_Junk (Stmt)
then
Stmt := First (Statements (Handled_Statement_Sequence (Stmt)));
end if;
-- Insertion point is after any exception label pushes, since we
-- want it covered by any local handlers.
while Nkind (Stmt) in N_Push_xxx_Label loop
Next (Stmt);
end loop;
-- Now we have the proper insertion point
Insert_Before (Stmt, Call);
else
Set_Handled_Statement_Sequence (N,
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (Call)));
end if;
end if;
Analyze (Call);
if Legacy_Elaboration_Checks then
Check_Task_Activation (N);
end if;
end Build_Task_Activation_Call;
-------------------------------
-- Build_Task_Allocate_Block --
-------------------------------
procedure Build_Task_Allocate_Block
(Actions : List_Id;
N : Node_Id;
Args : List_Id)
is
T : constant Entity_Id := Entity (Expression (N));
Init : constant Entity_Id := Base_Init_Proc (T);
Loc : constant Source_Ptr := Sloc (N);
Chain : constant Entity_Id :=
Make_Defining_Identifier (Loc, Name_uChain);
Blkent : constant Entity_Id := Make_Temporary (Loc, 'A');
Block : Node_Id;
begin
Block :=
Make_Block_Statement (Loc,
Identifier => New_Occurrence_Of (Blkent, Loc),
Declarations => New_List (
-- _Chain : Activation_Chain;
Make_Object_Declaration (Loc,
Defining_Identifier => Chain,
Aliased_Present => True,
Object_Definition =>
New_Occurrence_Of (RTE (RE_Activation_Chain), Loc))),
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (
-- Init (Args);
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (Init, Loc),
Parameter_Associations => Args),
-- Activate_Tasks (_Chain);
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Activate_Tasks), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Chain, Loc),
Attribute_Name => Name_Unchecked_Access))))),
Has_Created_Identifier => True,
Is_Task_Allocation_Block => True);
Append_To (Actions,
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier => Blkent,
Label_Construct => Block));
Append_To (Actions, Block);
Set_Activation_Chain_Entity (Block, Chain);
end Build_Task_Allocate_Block;
-----------------------------------------------
-- Build_Task_Allocate_Block_With_Init_Stmts --
-----------------------------------------------
procedure Build_Task_Allocate_Block_With_Init_Stmts
(Actions : List_Id;
N : Node_Id;
Init_Stmts : List_Id)
is
Loc : constant Source_Ptr := Sloc (N);
Chain : constant Entity_Id :=
Make_Defining_Identifier (Loc, Name_uChain);
Blkent : constant Entity_Id := Make_Temporary (Loc, 'A');
Block : Node_Id;
begin
Append_To (Init_Stmts,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Activate_Tasks), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Chain, Loc),
Attribute_Name => Name_Unchecked_Access))));
Block :=
Make_Block_Statement (Loc,
Identifier => New_Occurrence_Of (Blkent, Loc),
Declarations => New_List (
-- _Chain : Activation_Chain;
Make_Object_Declaration (Loc,
Defining_Identifier => Chain,
Aliased_Present => True,
Object_Definition =>
New_Occurrence_Of (RTE (RE_Activation_Chain), Loc))),
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Init_Stmts),
Has_Created_Identifier => True,
Is_Task_Allocation_Block => True);
Append_To (Actions,
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier => Blkent,
Label_Construct => Block));
Append_To (Actions, Block);
Set_Activation_Chain_Entity (Block, Chain);
end Build_Task_Allocate_Block_With_Init_Stmts;
-----------------------------------
-- Build_Task_Proc_Specification --
-----------------------------------
function Build_Task_Proc_Specification (T : Entity_Id) return Node_Id is
Loc : constant Source_Ptr := Sloc (T);
Spec_Id : Entity_Id;
begin
-- Case of explicit task type, suffix TB
if Comes_From_Source (T) then
Spec_Id :=
Make_Defining_Identifier (Loc, New_External_Name (Chars (T), "TB"));
-- Case of anonymous task type, suffix B
else
Spec_Id :=
Make_Defining_Identifier (Loc, New_External_Name (Chars (T), 'B'));
end if;
Set_Is_Internal (Spec_Id);
-- Associate the procedure with the task, if this is the declaration
-- (and not the body) of the procedure.
if No (Task_Body_Procedure (T)) then
Set_Task_Body_Procedure (T, Spec_Id);
end if;
return
Make_Procedure_Specification (Loc,
Defining_Unit_Name => Spec_Id,
Parameter_Specifications => New_List (
Make_Parameter_Specification (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uTask),
Parameter_Type =>
Make_Access_Definition (Loc,
Subtype_Mark =>
New_Occurrence_Of (Corresponding_Record_Type (T), Loc)))));
end Build_Task_Proc_Specification;
---------------------------------------
-- Build_Unprotected_Subprogram_Body --
---------------------------------------
function Build_Unprotected_Subprogram_Body
(N : Node_Id;
Pid : Node_Id) return Node_Id
is
Decls : constant List_Id := Declarations (N);
begin
-- Add renamings for the Protection object, discriminals, privals, and
-- the entry index constant for use by debugger.
Debug_Private_Data_Declarations (Decls);
-- Make an unprotected version of the subprogram for use within the same
-- object, with a new name and an additional parameter representing the
-- object.
return
Make_Subprogram_Body (Sloc (N),
Specification =>
Build_Protected_Sub_Specification (N, Pid, Unprotected_Mode),
Declarations => Decls,
Handled_Statement_Sequence => Handled_Statement_Sequence (N));
end Build_Unprotected_Subprogram_Body;
----------------------------
-- Collect_Entry_Families --
----------------------------
procedure Collect_Entry_Families
(Loc : Source_Ptr;
Cdecls : List_Id;
Current_Node : in out Node_Id;
Conctyp : Entity_Id)
is
Efam : Entity_Id;
Efam_Decl : Node_Id;
Efam_Type : Entity_Id;
begin
Efam := First_Entity (Conctyp);
while Present (Efam) loop
if Ekind (Efam) = E_Entry_Family then
Efam_Type := Make_Temporary (Loc, 'F');
declare
Eityp : constant Entity_Id := Entry_Index_Type (Efam);
Lo : constant Node_Id := Type_Low_Bound (Eityp);
Hi : constant Node_Id := Type_High_Bound (Eityp);
Bdecl : Node_Id;
Bityp : Entity_Id;
begin
Bityp := Base_Type (Eityp);
if Is_Potentially_Large_Family (Bityp, Conctyp, Lo, Hi) then
Bityp := Make_Temporary (Loc, 'B');
Bdecl :=
Make_Subtype_Declaration (Loc,
Defining_Identifier => Bityp,
Subtype_Indication =>
Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of (Standard_Integer, Loc),
Constraint =>
Make_Range_Constraint (Loc,
Range_Expression => Make_Range (Loc,
Make_Integer_Literal
(Loc, -Entry_Family_Bound),
Make_Integer_Literal
(Loc, Entry_Family_Bound - 1)))));
Insert_After (Current_Node, Bdecl);
Current_Node := Bdecl;
Analyze (Bdecl);
end if;
Efam_Decl :=
Make_Full_Type_Declaration (Loc,
Defining_Identifier => Efam_Type,
Type_Definition =>
Make_Unconstrained_Array_Definition (Loc,
Subtype_Marks =>
(New_List (New_Occurrence_Of (Bityp, Loc))),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication =>
New_Occurrence_Of (Standard_Character, Loc))));
end;
Insert_After (Current_Node, Efam_Decl);
Current_Node := Efam_Decl;
Analyze (Efam_Decl);
Append_To (Cdecls,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Chars (Efam)),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication =>
Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of (Efam_Type, Loc),
Constraint =>
Make_Index_Or_Discriminant_Constraint (Loc,
Constraints => New_List (
New_Occurrence_Of (Entry_Index_Type (Efam),
Loc)))))));
end if;
Next_Entity (Efam);
end loop;
end Collect_Entry_Families;
-----------------------
-- Concurrent_Object --
-----------------------
function Concurrent_Object
(Spec_Id : Entity_Id;
Conc_Typ : Entity_Id) return Entity_Id
is
begin
-- Parameter _O or _object
if Is_Protected_Type (Conc_Typ) then
return First_Formal (Protected_Body_Subprogram (Spec_Id));
-- Parameter _task
else
pragma Assert (Is_Task_Type (Conc_Typ));
return First_Formal (Task_Body_Procedure (Conc_Typ));
end if;
end Concurrent_Object;
----------------------
-- Copy_Result_Type --
----------------------
function Copy_Result_Type (Res : Node_Id) return Node_Id is
New_Res : constant Node_Id := New_Copy_Tree (Res);
Par_Spec : Node_Id;
Formal : Entity_Id;
begin
-- If the result type is an access_to_subprogram, we must create new
-- entities for its spec.
if Nkind (New_Res) = N_Access_Definition
and then Present (Access_To_Subprogram_Definition (New_Res))
then
-- Provide new entities for the formals
Par_Spec := First (Parameter_Specifications
(Access_To_Subprogram_Definition (New_Res)));
while Present (Par_Spec) loop
Formal := Defining_Identifier (Par_Spec);
Set_Defining_Identifier (Par_Spec,
Make_Defining_Identifier (Sloc (Formal), Chars (Formal)));
Next (Par_Spec);
end loop;
end if;
return New_Res;
end Copy_Result_Type;
--------------------
-- Concurrent_Ref --
--------------------
-- The expression returned for a reference to a concurrent object has the
-- form:
-- taskV!(name)._Task_Id
-- for a task, and
-- objectV!(name)._Object
-- for a protected object. For the case of an access to a concurrent
-- object, there is an extra explicit dereference:
-- taskV!(name.all)._Task_Id
-- objectV!(name.all)._Object
-- here taskV and objectV are the types for the associated records, which
-- contain the required _Task_Id and _Object fields for tasks and protected
-- objects, respectively.
-- For the case of a task type name, the expression is
-- Self;
-- i.e. a call to the Self function which returns precisely this Task_Id
-- For the case of a protected type name, the expression is
-- objectR
-- which is a renaming of the _object field of the current object
-- record, passed into protected operations as a parameter.
function Concurrent_Ref (N : Node_Id) return Node_Id is
Loc : constant Source_Ptr := Sloc (N);
Ntyp : constant Entity_Id := Etype (N);
Dtyp : Entity_Id;
Sel : Name_Id;
function Is_Current_Task (T : Entity_Id) return Boolean;
-- Check whether the reference is to the immediately enclosing task
-- type, or to an outer one (rare but legal).
---------------------
-- Is_Current_Task --
---------------------
function Is_Current_Task (T : Entity_Id) return Boolean is
Scop : Entity_Id;
begin
Scop := Current_Scope;
while Present (Scop) and then Scop /= Standard_Standard loop
if Scop = T then
return True;
elsif Is_Task_Type (Scop) then
return False;
-- If this is a procedure nested within the task type, we must
-- assume that it can be called from an inner task, and therefore
-- cannot treat it as a local reference.
elsif Is_Overloadable (Scop) and then In_Open_Scopes (T) then
return False;
else
Scop := Scope (Scop);
end if;
end loop;
-- We know that we are within the task body, so should have found it
-- in scope.
raise Program_Error;
end Is_Current_Task;
-- Start of processing for Concurrent_Ref
begin
if Is_Access_Type (Ntyp) then
Dtyp := Designated_Type (Ntyp);
if Is_Protected_Type (Dtyp) then
Sel := Name_uObject;
else
Sel := Name_uTask_Id;
end if;
return
Make_Selected_Component (Loc,
Prefix =>
Unchecked_Convert_To (Corresponding_Record_Type (Dtyp),
Make_Explicit_Dereference (Loc, N)),
Selector_Name => Make_Identifier (Loc, Sel));
elsif Is_Entity_Name (N) and then Is_Concurrent_Type (Entity (N)) then
if Is_Task_Type (Entity (N)) then
if Is_Current_Task (Entity (N)) then
return
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Self), Loc));
else
declare
Decl : Node_Id;
T_Self : constant Entity_Id := Make_Temporary (Loc, 'T');
T_Body : constant Node_Id :=
Parent (Corresponding_Body (Parent (Entity (N))));
begin
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => T_Self,
Object_Definition =>
New_Occurrence_Of (RTE (RO_ST_Task_Id), Loc),
Expression =>
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Self), Loc)));
Prepend (Decl, Declarations (T_Body));
Analyze (Decl);
Set_Scope (T_Self, Entity (N));
return New_Occurrence_Of (T_Self, Loc);
end;
end if;
else
pragma Assert (Is_Protected_Type (Entity (N)));
return
New_Occurrence_Of (Find_Protection_Object (Current_Scope), Loc);
end if;
else
if Is_Protected_Type (Ntyp) then
Sel := Name_uObject;
elsif Is_Task_Type (Ntyp) then
Sel := Name_uTask_Id;
else
raise Program_Error;
end if;
return
Make_Selected_Component (Loc,
Prefix =>
Unchecked_Convert_To (Corresponding_Record_Type (Ntyp),
New_Copy_Tree (N)),
Selector_Name => Make_Identifier (Loc, Sel));
end if;
end Concurrent_Ref;
------------------------
-- Convert_Concurrent --
------------------------
function Convert_Concurrent
(N : Node_Id;
Typ : Entity_Id) return Node_Id
is
begin
if not Is_Concurrent_Type (Typ) then
return N;
else
return
Unchecked_Convert_To
(Corresponding_Record_Type (Typ), New_Copy_Tree (N));
end if;
end Convert_Concurrent;
-------------------------------------
-- Create_Secondary_Stack_For_Task --
-------------------------------------
function Create_Secondary_Stack_For_Task (T : Node_Id) return Boolean is
begin
return
(Restriction_Active (No_Implicit_Heap_Allocations)
or else Restriction_Active (No_Implicit_Task_Allocations))
and then not Restriction_Active (No_Secondary_Stack)
and then Has_Rep_Pragma
(T, Name_Secondary_Stack_Size, Check_Parents => False);
end Create_Secondary_Stack_For_Task;
-------------------------------------
-- Debug_Private_Data_Declarations --
-------------------------------------
procedure Debug_Private_Data_Declarations (Decls : List_Id) is
Debug_Nod : Node_Id;
Decl : Node_Id;
begin
Decl := First (Decls);
while Present (Decl) and then not Comes_From_Source (Decl) loop
-- Declaration for concurrent entity _object and its access type,
-- along with the entry index subtype:
-- type prot_typVP is access prot_typV;
-- _object : prot_typVP := prot_typV (_O);
-- subtype Jnn is <Type of Index> range Low .. High;
if Nkind (Decl) in N_Full_Type_Declaration | N_Object_Declaration then
Set_Debug_Info_Needed (Defining_Identifier (Decl));
-- Declaration for the Protection object, discriminals, privals, and
-- entry index constant:
-- conc_typR : protection_typ renames _object._object;
-- discr_nameD : discr_typ renames _object.discr_name;
-- discr_nameD : discr_typ renames _task.discr_name;
-- prival_name : comp_typ renames _object.comp_name;
-- J : constant Jnn :=
-- Jnn'Val (_E - <Index expression> + Jnn'Pos (Jnn'First));
elsif Nkind (Decl) = N_Object_Renaming_Declaration then
Set_Debug_Info_Needed (Defining_Identifier (Decl));
Debug_Nod := Debug_Renaming_Declaration (Decl);
if Present (Debug_Nod) then
Insert_After (Decl, Debug_Nod);
end if;
end if;
Next (Decl);
end loop;
end Debug_Private_Data_Declarations;
------------------------------
-- Ensure_Statement_Present --
------------------------------
procedure Ensure_Statement_Present (Loc : Source_Ptr; Alt : Node_Id) is
Stmt : Node_Id;
begin
if Opt.Suppress_Control_Flow_Optimizations
and then Is_Empty_List (Statements (Alt))
then
Stmt := Make_Null_Statement (Loc);
-- Mark NULL statement as coming from source so that it is not
-- eliminated by GIGI.
-- Another covert channel. If this is a requirement, it must be
-- documented in sinfo/einfo ???
Set_Comes_From_Source (Stmt, True);
Set_Statements (Alt, New_List (Stmt));
end if;
end Ensure_Statement_Present;
----------------------------
-- Entry_Index_Expression --
----------------------------
function Entry_Index_Expression
(Sloc : Source_Ptr;
Ent : Entity_Id;
Index : Node_Id;
Ttyp : Entity_Id) return Node_Id
is
Expr : Node_Id;
Num : Node_Id;
Lo : Node_Id;
Hi : Node_Id;
Prev : Entity_Id;
S : Node_Id;
begin
-- The queues of entries and entry families appear in textual order in
-- the associated record. The entry index is computed as the sum of the
-- number of queues for all entries that precede the designated one, to
-- which is added the index expression, if this expression denotes a
-- member of a family.
-- The following is a place holder for the count of simple entries
Num := Make_Integer_Literal (Sloc, 1);
-- We construct an expression which is a series of addition operations.
-- The first operand is the number of single entries that precede this
-- one, the second operand is the index value relative to the start of
-- the referenced family, and the remaining operands are the lengths of
-- the entry families that precede this entry, i.e. the constructed
-- expression is:
-- number_simple_entries +
-- (s'pos (index-value) - s'pos (family'first)) + 1 +
-- family'length + ...
-- where index-value is the given index value, and s is the index
-- subtype (we have to use pos because the subtype might be an
-- enumeration type preventing direct subtraction). Note that the task
-- entry array is one-indexed.
-- The upper bound of the entry family may be a discriminant, so we
-- retrieve the lower bound explicitly to compute offset, rather than
-- using the index subtype which may mention a discriminant.
if Present (Index) then
S := Entry_Index_Type (Ent);
-- First make sure the index is in range if requested. The index type
-- is the pristine Entry_Index_Type of the entry.
if Do_Range_Check (Index) then
Generate_Range_Check (Index, S, CE_Range_Check_Failed);
end if;
Expr :=
Make_Op_Add (Sloc,
Left_Opnd => Num,
Right_Opnd =>
Family_Offset
(Sloc,
Make_Attribute_Reference (Sloc,
Attribute_Name => Name_Pos,
Prefix => New_Occurrence_Of (Base_Type (S), Sloc),
Expressions => New_List (Relocate_Node (Index))),
Type_Low_Bound (S),
Ttyp,
False));
else
Expr := Num;
end if;
-- Now add lengths of preceding entries and entry families
Prev := First_Entity (Ttyp);
while Chars (Prev) /= Chars (Ent)
or else (Ekind (Prev) /= Ekind (Ent))
or else not Sem_Ch6.Type_Conformant (Ent, Prev)
loop
if Ekind (Prev) = E_Entry then
Set_Intval (Num, Intval (Num) + 1);
elsif Ekind (Prev) = E_Entry_Family then
S := Entry_Index_Type (Prev);
Lo := Type_Low_Bound (S);
Hi := Type_High_Bound (S);
Expr :=
Make_Op_Add (Sloc,
Left_Opnd => Expr,
Right_Opnd => Family_Size (Sloc, Hi, Lo, Ttyp, False));
-- Other components are anonymous types to be ignored
else
null;
end if;
Next_Entity (Prev);
end loop;
return Expr;
end Entry_Index_Expression;
---------------------------
-- Establish_Task_Master --
---------------------------
procedure Establish_Task_Master (N : Node_Id) is
Call : Node_Id;
begin
if Restriction_Active (No_Task_Hierarchy) = False then
Call := Build_Runtime_Call (Sloc (N), RE_Enter_Master);
-- The block may have no declarations (and nevertheless be a task
-- master) if it contains a call that may return an object that
-- contains tasks.
if No (Declarations (N)) then
Set_Declarations (N, New_List (Call));
else
Prepend_To (Declarations (N), Call);
end if;
Analyze (Call);
end if;
end Establish_Task_Master;
--------------------------------
-- Expand_Accept_Declarations --
--------------------------------
-- Part of the expansion of an accept statement involves the creation of
-- a declaration that can be referenced from the statement sequence of
-- the accept:
-- Ann : Address;
-- This declaration is inserted immediately before the accept statement
-- and it is important that it be inserted before the statements of the
-- statement sequence are analyzed. Thus it would be too late to create
-- this declaration in the Expand_N_Accept_Statement routine, which is
-- why there is a separate procedure to be called directly from Sem_Ch9.
-- Ann is used to hold the address of the record containing the parameters
-- (see Expand_N_Entry_Call for more details on how this record is built).
-- References to the parameters do an unchecked conversion of this address
-- to a pointer to the required record type, and then access the field that
-- holds the value of the required parameter. The entity for the address
-- variable is held as the top stack element (i.e. the last element) of the
-- Accept_Address stack in the corresponding entry entity, and this element
-- must be set in place before the statements are processed.
-- The above description applies to the case of a stand alone accept
-- statement, i.e. one not appearing as part of a select alternative.
-- For the case of an accept that appears as part of a select alternative
-- of a selective accept, we must still create the declaration right away,
-- since Ann is needed immediately, but there is an important difference:
-- The declaration is inserted before the selective accept, not before
-- the accept statement (which is not part of a list anyway, and so would
-- not accommodate inserted declarations)
-- We only need one address variable for the entire selective accept. So
-- the Ann declaration is created only for the first accept alternative,
-- and subsequent accept alternatives reference the same Ann variable.
-- We can distinguish the two cases by seeing whether the accept statement
-- is part of a list. If not, then it must be in an accept alternative.
-- To expand the requeue statement, a label is provided at the end of the
-- accept statement or alternative of which it is a part, so that the
-- statement can be skipped after the requeue is complete. This label is
-- created here rather than during the expansion of the accept statement,
-- because it will be needed by any requeue statements within the accept,
-- which are expanded before the accept.
procedure Expand_Accept_Declarations (N : Node_Id; Ent : Entity_Id) is
Loc : constant Source_Ptr := Sloc (N);
Stats : constant Node_Id := Handled_Statement_Sequence (N);
Ann : Entity_Id := Empty;
Adecl : Node_Id;
Lab : Node_Id;
Ldecl : Node_Id;
Ldecl2 : Node_Id;
begin
if Expander_Active then
-- If we have no handled statement sequence, we may need to build
-- a dummy sequence consisting of a null statement. This can be
-- skipped if the trivial accept optimization is permitted.
if not Trivial_Accept_OK
and then (No (Stats) or else Null_Statements (Statements (Stats)))
then
Set_Handled_Statement_Sequence (N,
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (Make_Null_Statement (Loc))));
end if;
-- Create and declare two labels to be placed at the end of the
-- accept statement. The first label is used to allow requeues to
-- skip the remainder of entry processing. The second label is used
-- to skip the remainder of entry processing if the rendezvous
-- completes in the middle of the accept body.
if Present (Handled_Statement_Sequence (N)) then
declare
Ent : Entity_Id;
begin
Ent := Make_Temporary (Loc, 'L');
Lab := Make_Label (Loc, New_Occurrence_Of (Ent, Loc));
Ldecl :=
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier => Ent,
Label_Construct => Lab);
Append (Lab, Statements (Handled_Statement_Sequence (N)));
Ent := Make_Temporary (Loc, 'L');
Lab := Make_Label (Loc, New_Occurrence_Of (Ent, Loc));
Ldecl2 :=
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier => Ent,
Label_Construct => Lab);
Append (Lab, Statements (Handled_Statement_Sequence (N)));
end;
else
Ldecl := Empty;
Ldecl2 := Empty;
end if;
-- Case of stand alone accept statement
if Is_List_Member (N) then
if Present (Handled_Statement_Sequence (N)) then
Ann := Make_Temporary (Loc, 'A');
Adecl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Ann,
Object_Definition =>
New_Occurrence_Of (RTE (RE_Address), Loc));
Insert_Before_And_Analyze (N, Adecl);
Insert_Before_And_Analyze (N, Ldecl);
Insert_Before_And_Analyze (N, Ldecl2);
end if;
-- Case of accept statement which is in an accept alternative
else
declare
Acc_Alt : constant Node_Id := Parent (N);
Sel_Acc : constant Node_Id := Parent (Acc_Alt);
Alt : Node_Id;
begin
pragma Assert (Nkind (Acc_Alt) = N_Accept_Alternative);
pragma Assert (Nkind (Sel_Acc) = N_Selective_Accept);
-- ??? Consider a single label for select statements
if Present (Handled_Statement_Sequence (N)) then
Prepend (Ldecl2,
Statements (Handled_Statement_Sequence (N)));
Analyze (Ldecl2);
Prepend (Ldecl,
Statements (Handled_Statement_Sequence (N)));
Analyze (Ldecl);
end if;
-- Find first accept alternative of the selective accept. A
-- valid selective accept must have at least one accept in it.
Alt := First (Select_Alternatives (Sel_Acc));
while Nkind (Alt) /= N_Accept_Alternative loop
Next (Alt);
end loop;
-- If this is the first accept statement, then we have to
-- create the Ann variable, as for the stand alone case, except
-- that it is inserted before the selective accept. Similarly,
-- a label for requeue expansion must be declared.
if N = Accept_Statement (Alt) then
Ann := Make_Temporary (Loc, 'A');
Adecl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Ann,
Object_Definition =>
New_Occurrence_Of (RTE (RE_Address), Loc));
Insert_Before_And_Analyze (Sel_Acc, Adecl);
-- If this is not the first accept statement, then find the Ann
-- variable allocated by the first accept and use it.
else
Ann :=
Node (Last_Elmt (Accept_Address
(Entity (Entry_Direct_Name (Accept_Statement (Alt))))));
end if;
end;
end if;
-- Merge here with Ann either created or referenced, and Adecl
-- pointing to the corresponding declaration. Remaining processing
-- is the same for the two cases.
if Present (Ann) then
Append_Elmt (Ann, Accept_Address (Ent));
Set_Debug_Info_Needed (Ann);
end if;
-- Create renaming declarations for the entry formals. Each reference
-- to a formal becomes a dereference of a component of the parameter
-- block, whose address is held in Ann. These declarations are
-- eventually inserted into the accept block, and analyzed there so
-- that they have the proper scope for gdb and do not conflict with
-- other declarations.
if Present (Parameter_Specifications (N))
and then Present (Handled_Statement_Sequence (N))
then
declare
Comp : Entity_Id;
Decl : Node_Id;
Formal : Entity_Id;
New_F : Entity_Id;
Renamed_Formal : Node_Id;
begin
Push_Scope (Ent);
Formal := First_Formal (Ent);
while Present (Formal) loop
Comp := Entry_Component (Formal);
New_F := Make_Defining_Identifier (Loc, Chars (Formal));
Set_Etype (New_F, Etype (Formal));
Set_Scope (New_F, Ent);
-- Now we set debug info needed on New_F even though it does
-- not come from source, so that the debugger will get the
-- right information for these generated names.
Set_Debug_Info_Needed (New_F);
if Ekind (Formal) = E_In_Parameter then
Mutate_Ekind (New_F, E_Constant);
else
Mutate_Ekind (New_F, E_Variable);
Set_Extra_Constrained (New_F, Extra_Constrained (Formal));
end if;
Set_Actual_Subtype (New_F, Actual_Subtype (Formal));
Renamed_Formal :=
Make_Selected_Component (Loc,
Prefix =>
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (
Entry_Parameters_Type (Ent),
New_Occurrence_Of (Ann, Loc))),
Selector_Name =>
New_Occurrence_Of (Comp, Loc));
Decl :=
Build_Renamed_Formal_Declaration
(New_F, Formal, Comp, Renamed_Formal);
if No (Declarations (N)) then
Set_Declarations (N, New_List);
end if;
Append (Decl, Declarations (N));
Set_Renamed_Object (Formal, New_F);
Next_Formal (Formal);
end loop;
End_Scope;
end;
end if;
end if;
end Expand_Accept_Declarations;
---------------------------------------------
-- Expand_Access_Protected_Subprogram_Type --
---------------------------------------------
procedure Expand_Access_Protected_Subprogram_Type (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
T : constant Entity_Id := Defining_Identifier (N);
D_T : constant Entity_Id := Designated_Type (T);
D_T2 : constant Entity_Id := Make_Temporary (Loc, 'D');
E_T : constant Entity_Id := Make_Temporary (Loc, 'E');
P_List : constant List_Id :=
Build_Protected_Spec (N, RTE (RE_Address), D_T, False);
Comps : List_Id;
Decl1 : Node_Id;
Decl2 : Node_Id;
Def1 : Node_Id;
begin
-- Create access to subprogram with full signature
if Etype (D_T) /= Standard_Void_Type then
Def1 :=
Make_Access_Function_Definition (Loc,
Parameter_Specifications => P_List,
Result_Definition =>
Copy_Result_Type (Result_Definition (Type_Definition (N))));
else
Def1 :=
Make_Access_Procedure_Definition (Loc,
Parameter_Specifications => P_List);
end if;
Decl1 :=
Make_Full_Type_Declaration (Loc,
Defining_Identifier => D_T2,
Type_Definition => Def1);
-- Declare the new types before the original one since the latter will
-- refer to them through the Equivalent_Type slot.
Insert_Before_And_Analyze (N, Decl1);
-- Associate the access to subprogram with its original access to
-- protected subprogram type. Needed by the backend to know that this
-- type corresponds with an access to protected subprogram type.
Set_Original_Access_Type (D_T2, T);
-- Create Equivalent_Type, a record with two components for an access to
-- object and an access to subprogram.
Comps := New_List (
Make_Component_Declaration (Loc,
Defining_Identifier => Make_Temporary (Loc, 'P'),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication =>
New_Occurrence_Of (RTE (RE_Address), Loc))),
Make_Component_Declaration (Loc,
Defining_Identifier => Make_Temporary (Loc, 'S'),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication => New_Occurrence_Of (D_T2, Loc))));
Decl2 :=
Make_Full_Type_Declaration (Loc,
Defining_Identifier => E_T,
Type_Definition =>
Make_Record_Definition (Loc,
Component_List =>
Make_Component_List (Loc, Component_Items => Comps)));
Insert_Before_And_Analyze (N, Decl2);
Set_Equivalent_Type (T, E_T);
end Expand_Access_Protected_Subprogram_Type;
--------------------------
-- Expand_Entry_Barrier --
--------------------------
procedure Expand_Entry_Barrier (N : Node_Id; Ent : Entity_Id) is
Cond : constant Node_Id := Condition (Entry_Body_Formal_Part (N));
Prot : constant Entity_Id := Scope (Ent);
Spec_Decl : constant Node_Id := Parent (Prot);
Func_Id : Entity_Id := Empty;
-- The entity of the barrier function
function Is_Global_Entity (N : Node_Id) return Traverse_Result;
-- Check whether entity in Barrier is external to protected type.
-- If so, barrier may not be properly synchronized.
function Is_Pure_Barrier (N : Node_Id) return Traverse_Result;
-- Check whether N meets the Pure_Barriers restriction. Return OK if
-- so.
function Is_Simple_Barrier (N : Node_Id) return Boolean;
-- Check whether N meets the Simple_Barriers restriction. Return OK if
-- so.
----------------------
-- Is_Global_Entity --
----------------------
function Is_Global_Entity (N : Node_Id) return Traverse_Result is
E : Entity_Id;
S : Entity_Id;
begin
if Is_Entity_Name (N) and then Present (Entity (N)) then
E := Entity (N);
S := Scope (E);
if Ekind (E) = E_Variable then
-- If the variable is local to the barrier function generated
-- during expansion, it is ok. If expansion is not performed,
-- then Func is Empty so this test cannot succeed.
if Scope (E) = Func_Id then
null;
-- A protected call from a barrier to another object is ok
elsif Ekind (Etype (E)) = E_Protected_Type then
null;
-- If the variable is within the package body we consider
-- this safe. This is a common (if dubious) idiom.
elsif S = Scope (Prot)
and then Is_Package_Or_Generic_Package (S)
and then Nkind (Parent (E)) = N_Object_Declaration
and then Nkind (Parent (Parent (E))) = N_Package_Body
then
null;
else
Error_Msg_N ("potentially unsynchronized barrier??", N);
Error_Msg_N ("\& should be private component of type??", N);
end if;
end if;
end if;
return OK;
end Is_Global_Entity;
procedure Check_Unprotected_Barrier is
new Traverse_Proc (Is_Global_Entity);
-----------------------
-- Is_Simple_Barrier --
-----------------------
function Is_Simple_Barrier (N : Node_Id) return Boolean is
Renamed : Node_Id;
begin
if Is_Static_Expression (N) then
return True;
elsif Ada_Version >= Ada_2022
and then Nkind (N) in N_Selected_Component | N_Indexed_Component
and then Statically_Names_Object (N)
then
-- Restriction relaxed in Ada 2022 to allow statically named
-- subcomponents.
return Is_Simple_Barrier (Prefix (N));
end if;
-- Check if the name is a component of the protected object. If
-- the expander is active, the component has been transformed into a
-- renaming of _object.all.component. Original_Node is needed in case
-- validity checking is enabled, in which case the simple object
-- reference will have been rewritten.
if Expander_Active then
-- The expanded name may have been constant folded in which case
-- the original node is not necessarily an entity name (e.g. an
-- indexed component).
if not Is_Entity_Name (Original_Node (N)) then
return False;
end if;
Renamed := Renamed_Object (Entity (Original_Node (N)));
return
Present (Renamed)
and then Nkind (Renamed) = N_Selected_Component
and then Chars (Prefix (Prefix (Renamed))) = Name_uObject;
elsif not Is_Entity_Name (N) then
return False;
else
return Is_Protected_Component (Entity (N));
end if;
end Is_Simple_Barrier;
---------------------
-- Is_Pure_Barrier --
---------------------
function Is_Pure_Barrier (N : Node_Id) return Traverse_Result is
begin
case Nkind (N) is
when N_Expanded_Name
| N_Identifier
=>
-- Because of N_Expanded_Name case, return Skip instead of OK.
if No (Entity (N)) then
return Abandon;
elsif Is_Numeric_Type (Entity (N)) then
return Skip;
end if;
case Ekind (Entity (N)) is
when E_Constant
| E_Discriminant
=>
return Skip;
when E_Enumeration_Literal
| E_Named_Integer
| E_Named_Real
=>
if not Is_OK_Static_Expression (N) then
return Abandon;
end if;
return Skip;
when E_Component =>
return Skip;
when E_Variable =>
if Is_Simple_Barrier (N) then
return Skip;
end if;
when E_Function =>
-- The count attribute has been transformed into run-time
-- calls.
if Is_RTE (Entity (N), RE_Protected_Count)
or else Is_RTE (Entity (N), RE_Protected_Count_Entry)
then
return Skip;
end if;
when others =>
null;
end case;
when N_Function_Call =>
-- Function call checks are carried out as part of the analysis
-- of the function call name.
return OK;
when N_Character_Literal
| N_Integer_Literal
| N_Real_Literal
=>
return OK;
when N_Op_Boolean
| N_Op_Not
=>
if Ekind (Entity (N)) = E_Operator then
return OK;
end if;
when N_Short_Circuit
| N_If_Expression
| N_Case_Expression
=>
return OK;
when N_Indexed_Component | N_Selected_Component =>
if Statically_Names_Object (N) then
return Is_Pure_Barrier (Prefix (N));
else
return Abandon;
end if;
when N_Case_Expression_Alternative =>
-- do not traverse Discrete_Choices subtree
if Is_Pure_Barrier (Expression (N)) /= Abandon then
return Skip;
end if;
when N_Expression_With_Actions =>
-- this may occur in the case of a Count attribute reference
if Original_Node (N) /= N
and then Is_Pure_Barrier (Original_Node (N)) /= Abandon
then
return Skip;
end if;
when N_Membership_Test =>
if Is_Pure_Barrier (Left_Opnd (N)) /= Abandon
and then All_Membership_Choices_Static (N)
then
return Skip;
end if;
when N_Type_Conversion =>
-- Conversions to Universal_Integer do not raise constraint
-- errors. Likewise if the expression's type is statically
-- compatible with the target's type.
if Etype (N) = Universal_Integer
or else Subtypes_Statically_Compatible
(Etype (Expression (N)), Etype (N))
then
return OK;
end if;
when N_Unchecked_Type_Conversion =>
return OK;
when others =>
null;
end case;
return Abandon;
end Is_Pure_Barrier;
function Check_Pure_Barriers is new Traverse_Func (Is_Pure_Barrier);
-- Local variables
Cond_Id : Entity_Id;
Entry_Body : Node_Id;
Func_Body : Node_Id := Empty;
-- Start of processing for Expand_Entry_Barrier
begin
if No_Run_Time_Mode then
Error_Msg_CRT ("entry barrier", N);
return;
end if;
-- Prevent cascaded errors
if Nkind (Cond) = N_Error then
return;
end if;
-- The body of the entry barrier must be analyzed in the context of the
-- protected object, but its scope is external to it, just as any other
-- unprotected version of a protected operation. The specification has
-- been produced when the protected type declaration was elaborated. We
-- build the body, insert it in the enclosing scope, but analyze it in
-- the current context. A more uniform approach would be to treat the
-- barrier just as a protected function, and discard the protected
-- version of it because it is never called.
if Expander_Active then
Func_Body := Build_Barrier_Function (N, Ent, Prot);
Func_Id := Barrier_Function (Ent);
Set_Corresponding_Spec (Func_Body, Func_Id);
Entry_Body := Parent (Corresponding_Body (Spec_Decl));
if Nkind (Parent (Entry_Body)) = N_Subunit then
Entry_Body := Corresponding_Stub (Parent (Entry_Body));
end if;
Insert_Before_And_Analyze (Entry_Body, Func_Body);
Set_Discriminals (Spec_Decl);
Set_Scope (Func_Id, Scope (Prot));
else
Analyze_And_Resolve (Cond, Any_Boolean);
end if;
-- Check Simple_Barriers and Pure_Barriers restrictions.
-- Note that it is safe to be calling Check_Restriction from here, even
-- though this is part of the expander, since Expand_Entry_Barrier is
-- called from Sem_Ch9 even in -gnatc mode.
if not Is_Simple_Barrier (Cond) then
-- flag restriction violation
Check_Restriction (Simple_Barriers, Cond);
end if;
if Check_Pure_Barriers (Cond) = Abandon then
-- flag restriction violation
Check_Restriction (Pure_Barriers, Cond);
-- Emit warning if barrier contains global entities and is thus
-- potentially unsynchronized (if Pure_Barriers restrictions
-- are met then no need to check for this).
Check_Unprotected_Barrier (Cond);
end if;
if Is_Entity_Name (Cond) then
Cond_Id := Entity (Cond);
-- Perform a small optimization of simple barrier functions. If the
-- scope of the condition's entity is not the barrier function, then
-- the condition does not depend on any of the generated renamings.
-- If this is the case, eliminate the renamings as they are useless.
-- This optimization is not performed when the condition was folded
-- and validity checks are in effect because the original condition
-- may have produced at least one check that depends on the generated
-- renamings.
if Expander_Active
and then Scope (Cond_Id) /= Func_Id
and then not Validity_Check_Operands
then
Set_Declarations (Func_Body, Empty_List);
end if;
-- Note that after analysis variables in this context will be
-- replaced by the corresponding prival, that is to say a renaming
-- of a selected component of the form _Object.Var. If expansion is
-- disabled, as within a generic, we check that the entity appears in
-- the current scope.
end if;
end Expand_Entry_Barrier;
------------------------------
-- Expand_N_Abort_Statement --
------------------------------
-- Expand abort T1, T2, .. Tn; into:
-- Abort_Tasks (Task_List'(1 => T1.Task_Id, 2 => T2.Task_Id ...))
procedure Expand_N_Abort_Statement (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Tlist : constant List_Id := Names (N);
Count : Nat;
Aggr : Node_Id;
Tasknm : Node_Id;
begin
Aggr := Make_Aggregate (Loc, Component_Associations => New_List);
Count := 0;
Tasknm := First (Tlist);
while Present (Tasknm) loop
Count := Count + 1;
-- A task interface class-wide type object is being aborted. Retrieve
-- its _task_id by calling a dispatching routine.
if Ada_Version >= Ada_2005
and then Ekind (Etype (Tasknm)) = E_Class_Wide_Type
and then Is_Interface (Etype (Tasknm))
and then Is_Task_Interface (Etype (Tasknm))
then
Append_To (Component_Associations (Aggr),
Make_Component_Association (Loc,
Choices => New_List (Make_Integer_Literal (Loc, Count)),
Expression =>
-- Task_Id (Tasknm._disp_get_task_id)
Unchecked_Convert_To
(RTE (RO_ST_Task_Id),
Make_Selected_Component (Loc,
Prefix => New_Copy_Tree (Tasknm),
Selector_Name =>
Make_Identifier (Loc, Name_uDisp_Get_Task_Id)))));
else
Append_To (Component_Associations (Aggr),
Make_Component_Association (Loc,
Choices => New_List (Make_Integer_Literal (Loc, Count)),
Expression => Concurrent_Ref (Tasknm)));
end if;
Next (Tasknm);
end loop;
Rewrite (N,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Abort_Tasks), Loc),
Parameter_Associations => New_List (
Make_Qualified_Expression (Loc,
Subtype_Mark => New_Occurrence_Of (RTE (RE_Task_List), Loc),
Expression => Aggr))));
Analyze (N);
end Expand_N_Abort_Statement;
-------------------------------
-- Expand_N_Accept_Statement --
-------------------------------
-- This procedure handles expansion of accept statements that stand alone,
-- i.e. they are not part of an accept alternative. The expansion of
-- accept statement in accept alternatives is handled by the routines
-- Expand_N_Accept_Alternative and Expand_N_Selective_Accept. The
-- following description applies only to stand alone accept statements.
-- If there is no handled statement sequence, or only null statements, then
-- this is called a trivial accept, and the expansion is:
-- Accept_Trivial (entry-index)
-- If there is a handled statement sequence, then the expansion is:
-- Ann : Address;
-- {Lnn : Label}
-- begin
-- begin
-- Accept_Call (entry-index, Ann);
-- Renaming_Declarations for formals
-- <statement sequence from N_Accept_Statement node>
-- Complete_Rendezvous;
-- <<Lnn>>
--
-- exception
-- when ... =>
-- <exception handler from N_Accept_Statement node>
-- Complete_Rendezvous;
-- when ... =>
-- <exception handler from N_Accept_Statement node>
-- Complete_Rendezvous;
-- ...
-- end;
-- exception
-- when all others =>
-- Exceptional_Complete_Rendezvous (Get_GNAT_Exception);
-- end;
-- The first three declarations were already inserted ahead of the accept
-- statement by the Expand_Accept_Declarations procedure, which was called
-- directly from the semantics during analysis of the accept statement,
-- before analyzing its contained statements.
-- The declarations from the N_Accept_Statement, as noted in Sinfo, come
-- from possible expansion activity (the original source of course does
-- not have any declarations associated with the accept statement, since
-- an accept statement has no declarative part). In particular, if the
-- expander is active, the first such declaration is the declaration of
-- the Accept_Params_Ptr entity (see Sem_Ch9.Analyze_Accept_Statement).
-- The two blocks are merged into a single block if the inner block has
-- no exception handlers, but otherwise two blocks are required, since
-- exceptions might be raised in the exception handlers of the inner
-- block, and Exceptional_Complete_Rendezvous must be called.
procedure Expand_N_Accept_Statement (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Stats : constant Node_Id := Handled_Statement_Sequence (N);
Ename : constant Node_Id := Entry_Direct_Name (N);
Eindx : constant Node_Id := Entry_Index (N);
Eent : constant Entity_Id := Entity (Ename);
Acstack : constant Elist_Id := Accept_Address (Eent);
Ann : constant Entity_Id := Node (Last_Elmt (Acstack));
Ttyp : constant Entity_Id := Etype (Scope (Eent));
Blkent : Entity_Id;
Call : Node_Id;
Block : Node_Id;
begin
-- If the accept statement is not part of a list, then its parent must
-- be an accept alternative, and, as described above, we do not do any
-- expansion for such accept statements at this level.
if not Is_List_Member (N) then
pragma Assert (Nkind (Parent (N)) = N_Accept_Alternative);
return;
-- Trivial accept case (no statement sequence, or null statements).
-- If the accept statement has declarations, then just insert them
-- before the procedure call.
elsif Trivial_Accept_OK
and then (No (Stats) or else Null_Statements (Statements (Stats)))
then
-- Remove declarations for renamings, because the parameter block
-- will not be assigned.
declare
D : Node_Id;
Next_D : Node_Id;
begin
D := First (Declarations (N));
while Present (D) loop
Next_D := Next (D);
if Nkind (D) = N_Object_Renaming_Declaration then
Remove (D);
end if;
D := Next_D;
end loop;
end;
if Present (Declarations (N)) then
Insert_Actions (N, Declarations (N));
end if;
Rewrite (N,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Accept_Trivial), Loc),
Parameter_Associations => New_List (
Entry_Index_Expression (Loc, Entity (Ename), Eindx, Ttyp))));
Analyze (N);
-- Ada 2022 (AI12-0279)
if Has_Yield_Aspect (Eent)
and then RTE_Available (RE_Yield)
then
Insert_Action_After (N,
Make_Procedure_Call_Statement (Loc,
New_Occurrence_Of (RTE (RE_Yield), Loc)));
end if;
-- Discard Entry_Address that was created for it, so it will not be
-- emitted if this accept statement is in the statement part of a
-- delay alternative.
if Present (Stats) then
Remove_Last_Elmt (Acstack);
end if;
-- Case of statement sequence present
else
-- Construct the block, using the declarations from the accept
-- statement if any to initialize the declarations of the block.
Blkent := Make_Temporary (Loc, 'A');
Mutate_Ekind (Blkent, E_Block);
Set_Etype (Blkent, Standard_Void_Type);
Set_Scope (Blkent, Current_Scope);
Block :=
Make_Block_Statement (Loc,
Identifier => New_Occurrence_Of (Blkent, Loc),
Declarations => Declarations (N),
Handled_Statement_Sequence => Build_Accept_Body (N));
-- Reset the Scope of local entities associated with the accept
-- statement (that currently reference the entry scope) to the
-- block scope, to avoid having references to the locals treated
-- as up-level references.
Reset_Scopes_To (Block, Blkent);
-- For the analysis of the generated declarations, the parent node
-- must be properly set.
Set_Parent (Block, Parent (N));
Set_Parent (Blkent, Block);
-- Prepend call to Accept_Call to main statement sequence If the
-- accept has exception handlers, the statement sequence is wrapped
-- in a block. Insert call and renaming declarations in the
-- declarations of the block, so they are elaborated before the
-- handlers.
Call :=
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Accept_Call), Loc),
Parameter_Associations => New_List (
Entry_Index_Expression (Loc, Entity (Ename), Eindx, Ttyp),
New_Occurrence_Of (Ann, Loc)));
if Parent (Stats) = N then
Prepend (Call, Statements (Stats));
else
Set_Declarations (Parent (Stats), New_List (Call));
end if;
Analyze (Call);
Push_Scope (Blkent);
declare
D : Node_Id;
Next_D : Node_Id;
Typ : Entity_Id;
begin
D := First (Declarations (N));
while Present (D) loop
Next_D := Next (D);
if Nkind (D) = N_Object_Renaming_Declaration then
-- The renaming declarations for the formals were created
-- during analysis of the accept statement, and attached to
-- the list of declarations. Place them now in the context
-- of the accept block or subprogram.
Remove (D);
Typ := Entity (Subtype_Mark (D));
Insert_After (Call, D);
Analyze (D);
-- If the formal is class_wide, it does not have an actual
-- subtype. The analysis of the renaming declaration creates
-- one, but we need to retain the class-wide nature of the
-- entity.
if Is_Class_Wide_Type (Typ) then
Set_Etype (Defining_Identifier (D), Typ);
end if;
end if;
D := Next_D;
end loop;
end;
End_Scope;
-- Replace the accept statement by the new block
Rewrite (N, Block);
Analyze (N);
-- Last step is to unstack the Accept_Address value
Remove_Last_Elmt (Acstack);
end if;
end Expand_N_Accept_Statement;
----------------------------------
-- Expand_N_Asynchronous_Select --
----------------------------------
-- This procedure assumes that the trigger statement is an entry call or
-- a dispatching procedure call. A delay alternative should already have
-- been expanded into an entry call to the appropriate delay object Wait
-- entry.
-- If the trigger is a task entry call, the select is implemented with
-- a Task_Entry_Call:
-- declare
-- B : Boolean;
-- C : Boolean;
-- P : parms := (parm, parm, parm);
-- -- Clean is added by Exp_Ch7.Expand_Cleanup_Actions
-- procedure _clean is
-- begin
-- ...
-- Cancel_Task_Entry_Call (C);
-- ...
-- end _clean;
-- begin
-- Abort_Defer;
-- Task_Entry_Call
-- (<acceptor-task>, -- Acceptor
-- <entry-index>, -- E
-- P'Address, -- Uninterpreted_Data
-- Asynchronous_Call, -- Mode
-- B); -- Rendezvous_Successful
-- begin
-- begin
-- Abort_Undefer;
-- <abortable-part>
-- at end
-- _clean; -- Added by Exp_Ch7.Expand_Cleanup_Actions
-- end;
-- exception
-- when Abort_Signal => Abort_Undefer;
-- end;
-- parm := P.param;
-- parm := P.param;
-- ...
-- if not C then
-- <triggered-statements>
-- end if;
-- end;
-- Note that Build_Simple_Entry_Call is used to expand the entry of the
-- asynchronous entry call (by Expand_N_Entry_Call_Statement procedure)
-- as follows:
-- declare
-- P : parms := (parm, parm, parm);
-- begin
-- Call_Simple (acceptor-task, entry-index, P'Address);
-- parm := P.param;
-- parm := P.param;
-- ...
-- end;
-- so the task at hand is to convert the latter expansion into the former
-- If the trigger is a protected entry call, the select is implemented
-- with Protected_Entry_Call:
-- declare
-- P : E1_Params := (param, param, param);
-- Bnn : Communications_Block;
-- begin
-- declare
-- -- Clean is added by Exp_Ch7.Expand_Cleanup_Actions
-- procedure _clean is
-- begin
-- ...
-- if Enqueued (Bnn) then
-- Cancel_Protected_Entry_Call (Bnn);
-- end if;
-- ...
-- end _clean;
-- begin
-- begin
-- Protected_Entry_Call
-- (po._object'Access, -- Object
-- <entry index>, -- E
-- P'Address, -- Uninterpreted_Data
-- Asynchronous_Call, -- Mode
-- Bnn); -- Block
-- if Enqueued (Bnn) then
-- <abortable-part>
-- end if;
-- at end
-- _clean; -- Added by Exp_Ch7.Expand_Cleanup_Actions
-- end;
-- exception
-- when Abort_Signal => Abort_Undefer;
-- end;
-- if not Cancelled (Bnn) then
-- <triggered-statements>
-- end if;
-- end;
-- Build_Simple_Entry_Call is used to expand the all to a simple protected
-- entry call:
-- declare
-- P : E1_Params := (param, param, param);
-- Bnn : Communications_Block;
-- begin
-- Protected_Entry_Call
-- (po._object'Access, -- Object
-- <entry index>, -- E
-- P'Address, -- Uninterpreted_Data
-- Simple_Call, -- Mode
-- Bnn); -- Block
-- parm := P.param;
-- parm := P.param;
-- ...
-- end;
-- Ada 2005 (AI-345): If the trigger is a dispatching call, the select is
-- expanded into:
-- declare
-- B : Boolean := False;
-- Bnn : Communication_Block;
-- C : Ada.Tags.Prim_Op_Kind;
-- D : System.Storage_Elements.Dummy_Communication_Block;
-- K : Ada.Tags.Tagged_Kind :=
-- Ada.Tags.Get_Tagged_Kind (Ada.Tags.Tag (<object>));
-- P : Parameters := (Param1 .. ParamN);
-- S : Integer;
-- U : Boolean;
-- begin
-- if K = Ada.Tags.TK_Limited_Tagged
-- or else K = Ada.Tags.TK_Tagged
-- then
-- <dispatching-call>;
-- <triggering-statements>;
-- else
-- S :=
-- Ada.Tags.Get_Offset_Index
-- (Ada.Tags.Tag (<object>), DT_Position (<dispatching-call>));
-- _Disp_Get_Prim_Op_Kind (<object>, S, C);
-- if C = POK_Protected_Entry then
-- declare
-- procedure _clean is
-- begin
-- if Enqueued (Bnn) then
-- Cancel_Protected_Entry_Call (Bnn);
-- end if;
-- end _clean;
-- begin
-- begin
-- _Disp_Asynchronous_Select
-- (<object>, S, P'Address, D, B);
-- Bnn := Communication_Block (D);
-- Param1 := P.Param1;
-- ...
-- ParamN := P.ParamN;
-- if Enqueued (Bnn) then
-- <abortable-statements>
-- end if;
-- at end
-- _clean; -- Added by Exp_Ch7.Expand_Cleanup_Actions
-- end;
-- exception
-- when Abort_Signal => Abort_Undefer;
-- end;
-- if not Cancelled (Bnn) then
-- <triggering-statements>
-- end if;
-- elsif C = POK_Task_Entry then
-- declare
-- procedure _clean is
-- begin
-- Cancel_Task_Entry_Call (U);
-- end _clean;
-- begin
-- Abort_Defer;
-- _Disp_Asynchronous_Select
-- (<object>, S, P'Address, D, B);
-- Bnn := Communication_Bloc (D);
-- Param1 := P.Param1;
-- ...
-- ParamN := P.ParamN;
-- begin
-- begin
-- Abort_Undefer;
-- <abortable-statements>
-- at end
-- _clean; -- Added by Exp_Ch7.Expand_Cleanup_Actions
-- end;
-- exception
-- when Abort_Signal => Abort_Undefer;
-- end;
-- if not U then
-- <triggering-statements>
-- end if;
-- end;
-- else
-- <dispatching-call>;
-- <triggering-statements>
-- end if;
-- end if;
-- end;
-- The job is to convert this to the asynchronous form
-- If the trigger is a delay statement, it will have been expanded into
-- a call to one of the GNARL delay procedures. This routine will convert
-- this into a protected entry call on a delay object and then continue
-- processing as for a protected entry call trigger. This requires
-- declaring a Delay_Block object and adding a pointer to this object to
-- the parameter list of the delay procedure to form the parameter list of
-- the entry call. This object is used by the runtime to queue the delay
-- request.
-- For a description of the use of P and the assignments after the call,
-- see Expand_N_Entry_Call_Statement.
procedure Expand_N_Asynchronous_Select (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Abrt : constant Node_Id := Abortable_Part (N);
Trig : constant Node_Id := Triggering_Alternative (N);
Abort_Block_Ent : Entity_Id;
Abortable_Block : Node_Id;
Actuals : List_Id;
Astats : List_Id;
Blk_Ent : constant Entity_Id := Make_Temporary (Loc, 'A');
Blk_Typ : Entity_Id;
Call : Node_Id;
Call_Ent : Entity_Id;
Cancel_Param : Entity_Id;
Cleanup_Block : Node_Id;
Cleanup_Block_Ent : Entity_Id;
Cleanup_Stmts : List_Id;
Conc_Typ_Stmts : List_Id;
Concval : Node_Id;
Dblock_Ent : Entity_Id;
Decl : Node_Id;
Decls : List_Id;
Ecall : Node_Id;
Ename : Node_Id;
Enqueue_Call : Node_Id;
Formals : List_Id;
Hdle : List_Id;
Index : Node_Id;
Lim_Typ_Stmts : List_Id;
N_Orig : Node_Id;
Obj : Entity_Id;
Param : Node_Id;
Params : List_Id;
Pdef : Entity_Id;
ProtE_Stmts : List_Id;
ProtP_Stmts : List_Id;
Stmt : Node_Id;
Stmts : List_Id;
TaskE_Stmts : List_Id;
Tstats : List_Id;
B : Entity_Id; -- Call status flag
Bnn : Entity_Id; -- Communication block
C : Entity_Id; -- Call kind
K : Entity_Id; -- Tagged kind
P : Entity_Id; -- Parameter block
S : Entity_Id; -- Primitive operation slot
T : Entity_Id; -- Additional status flag
procedure Rewrite_Abortable_Part;
-- If the trigger is a dispatching call, the expansion inserts multiple
-- copies of the abortable part. This is both inefficient, and may lead
-- to duplicate definitions that the back-end will reject, when the
-- abortable part includes loops. This procedure rewrites the abortable
-- part into a call to a generated procedure.
----------------------------
-- Rewrite_Abortable_Part --
----------------------------
procedure Rewrite_Abortable_Part is
Proc : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
Decl : Node_Id;
begin
Decl :=
Make_Subprogram_Body (Loc,
Specification =>
Make_Procedure_Specification (Loc, Defining_Unit_Name => Proc),
Declarations => New_List,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Astats));
Insert_Before (N, Decl);
Analyze (Decl);
-- Rewrite abortable part into a call to this procedure
Astats :=
New_List (
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (Proc, Loc)));
end Rewrite_Abortable_Part;
-- Start of processing for Expand_N_Asynchronous_Select
begin
-- Asynchronous select is not supported on restricted runtimes. Don't
-- try to expand.
if Restricted_Profile then
return;
end if;
Process_Statements_For_Controlled_Objects (Trig);
Process_Statements_For_Controlled_Objects (Abrt);
Ecall := Triggering_Statement (Trig);
Ensure_Statement_Present (Sloc (Ecall), Trig);
-- Retrieve Astats and Tstats now because the finalization machinery may
-- wrap them in blocks.
Astats := Statements (Abrt);
Tstats := Statements (Trig);
-- The arguments in the call may require dynamic allocation, and the
-- call statement may have been transformed into a block. The block
-- may contain additional declarations for internal entities, and the
-- original call is found by sequential search.
if Nkind (Ecall) = N_Block_Statement then
Ecall := First (Statements (Handled_Statement_Sequence (Ecall)));
while Nkind (Ecall) not in
N_Procedure_Call_Statement | N_Entry_Call_Statement
loop
Next (Ecall);
end loop;
end if;
-- This is either a dispatching call or a delay statement used as a
-- trigger which was expanded into a procedure call.
if Nkind (Ecall) = N_Procedure_Call_Statement then
if Ada_Version >= Ada_2005
and then
(No (Original_Node (Ecall))
or else Nkind (Original_Node (Ecall)) not in N_Delay_Statement)
then
Extract_Dispatching_Call (Ecall, Call_Ent, Obj, Actuals, Formals);
Rewrite_Abortable_Part;
Decls := New_List;
Stmts := New_List;
-- Call status flag processing, generate:
-- B : Boolean := False;
B := Build_B (Loc, Decls);
-- Communication block processing, generate:
-- Bnn : Communication_Block;
Bnn := Make_Temporary (Loc, 'B');
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => Bnn,
Object_Definition =>
New_Occurrence_Of (RTE (RE_Communication_Block), Loc)));
-- Call kind processing, generate:
-- C : Ada.Tags.Prim_Op_Kind;
C := Build_C (Loc, Decls);
-- Tagged kind processing, generate:
-- K : Ada.Tags.Tagged_Kind :=
-- Ada.Tags.Get_Tagged_Kind (Ada.Tags.Tag (<object>));
-- Dummy communication block, generate:
-- D : Dummy_Communication_Block;
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uD),
Object_Definition =>
New_Occurrence_Of
(RTE (RE_Dummy_Communication_Block), Loc)));
K := Build_K (Loc, Decls, Obj);
-- Parameter block processing
Blk_Typ := Build_Parameter_Block
(Loc, Actuals, Formals, Decls);
P := Parameter_Block_Pack
(Loc, Blk_Typ, Actuals, Formals, Decls, Stmts);
-- Dispatch table slot processing, generate:
-- S : Integer;
S := Build_S (Loc, Decls);
-- Additional status flag processing, generate:
-- Tnn : Boolean;
T := Make_Temporary (Loc, 'T');
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => T,
Object_Definition =>
New_Occurrence_Of (Standard_Boolean, Loc)));
------------------------------
-- Protected entry handling --
------------------------------
-- Generate:
-- Param1 := P.Param1;
-- ...
-- ParamN := P.ParamN;
Cleanup_Stmts := Parameter_Block_Unpack (Loc, P, Actuals, Formals);
-- Generate:
-- Bnn := Communication_Block (D);
Prepend_To (Cleanup_Stmts,
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (Bnn, Loc),
Expression =>
Unchecked_Convert_To
(RTE (RE_Communication_Block),
Make_Identifier (Loc, Name_uD))));
-- Generate:
-- _Disp_Asynchronous_Select (<object>, S, P'Address, D, B);
Prepend_To (Cleanup_Stmts,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of
(Find_Prim_Op
(Etype (Etype (Obj)), Name_uDisp_Asynchronous_Select),
Loc),
Parameter_Associations =>
New_List (
New_Copy_Tree (Obj), -- <object>
New_Occurrence_Of (S, Loc), -- S
Make_Attribute_Reference (Loc, -- P'Address
Prefix => New_Occurrence_Of (P, Loc),
Attribute_Name => Name_Address),
Make_Identifier (Loc, Name_uD), -- D
New_Occurrence_Of (B, Loc)))); -- B
-- Generate:
-- if Enqueued (Bnn) then
-- <abortable-statements>
-- end if;
Append_To (Cleanup_Stmts,
Make_Implicit_If_Statement (N,
Condition =>
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Enqueued), Loc),
Parameter_Associations =>
New_List (New_Occurrence_Of (Bnn, Loc))),
Then_Statements =>
New_Copy_List_Tree (Astats)));
-- Wrap the statements in a block. Exp_Ch7.Expand_Cleanup_Actions
-- will then generate a _clean for the communication block Bnn.
-- Generate:
-- declare
-- procedure _clean is
-- begin
-- if Enqueued (Bnn) then
-- Cancel_Protected_Entry_Call (Bnn);
-- end if;
-- end _clean;
-- begin
-- Cleanup_Stmts
-- at end
-- _clean;
-- end;
Cleanup_Block_Ent := Make_Temporary (Loc, 'C');
Cleanup_Block :=
Build_Cleanup_Block (Loc, Cleanup_Block_Ent, Cleanup_Stmts, Bnn);
-- Wrap the cleanup block in an exception handling block
-- Generate:
-- begin
-- Cleanup_Block
-- exception
-- when Abort_Signal => Abort_Undefer;
-- end;
Abort_Block_Ent := Make_Temporary (Loc, 'A');
ProtE_Stmts :=
New_List (
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier => Abort_Block_Ent),
Build_Abort_Block
(Loc, Abort_Block_Ent, Cleanup_Block_Ent, Cleanup_Block));
-- Generate:
-- if not Cancelled (Bnn) then
-- <triggering-statements>
-- end if;
Append_To (ProtE_Stmts,
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Not (Loc,
Right_Opnd =>
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Cancelled), Loc),
Parameter_Associations =>
New_List (New_Occurrence_Of (Bnn, Loc)))),
Then_Statements =>
New_Copy_List_Tree (Tstats)));
-------------------------
-- Task entry handling --
-------------------------
-- Generate:
-- Param1 := P.Param1;
-- ...
-- ParamN := P.ParamN;
TaskE_Stmts := Parameter_Block_Unpack (Loc, P, Actuals, Formals);
-- Generate:
-- Bnn := Communication_Block (D);
Append_To (TaskE_Stmts,
Make_Assignment_Statement (Loc,
Name =>
New_Occurrence_Of (Bnn, Loc),
Expression =>
Unchecked_Convert_To
(RTE (RE_Communication_Block),
Make_Identifier (Loc, Name_uD))));
-- Generate:
-- _Disp_Asynchronous_Select (<object>, S, P'Address, D, B);
Prepend_To (TaskE_Stmts,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of (
Find_Prim_Op (Etype (Etype (Obj)),
Name_uDisp_Asynchronous_Select),
Loc),
Parameter_Associations => New_List (
New_Copy_Tree (Obj), -- <object>
New_Occurrence_Of (S, Loc), -- S
Make_Attribute_Reference (Loc, -- P'Address
Prefix => New_Occurrence_Of (P, Loc),
Attribute_Name => Name_Address),
Make_Identifier (Loc, Name_uD), -- D
New_Occurrence_Of (B, Loc)))); -- B
-- Generate:
-- Abort_Defer;
Prepend_To (TaskE_Stmts, Build_Runtime_Call (Loc, RE_Abort_Defer));
-- Generate:
-- Abort_Undefer;
-- <abortable-statements>
Cleanup_Stmts := New_Copy_List_Tree (Astats);
Prepend_To
(Cleanup_Stmts, Build_Runtime_Call (Loc, RE_Abort_Undefer));
-- Wrap the statements in a block. Exp_Ch7.Expand_Cleanup_Actions
-- will generate a _clean for the additional status flag.
-- Generate:
-- declare
-- procedure _clean is
-- begin
-- Cancel_Task_Entry_Call (U);
-- end _clean;
-- begin
-- Cleanup_Stmts
-- at end
-- _clean;
-- end;
Cleanup_Block_Ent := Make_Temporary (Loc, 'C');
Cleanup_Block :=
Build_Cleanup_Block (Loc, Cleanup_Block_Ent, Cleanup_Stmts, T);
-- Wrap the cleanup block in an exception handling block
-- Generate:
-- begin
-- Cleanup_Block
-- exception
-- when Abort_Signal => Abort_Undefer;
-- end;
Abort_Block_Ent := Make_Temporary (Loc, 'A');
Append_To (TaskE_Stmts,
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier => Abort_Block_Ent));
Append_To (TaskE_Stmts,
Build_Abort_Block
(Loc, Abort_Block_Ent, Cleanup_Block_Ent, Cleanup_Block));
-- Generate:
-- if not T then
-- <triggering-statements>
-- end if;
Append_To (TaskE_Stmts,
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Not (Loc, Right_Opnd => New_Occurrence_Of (T, Loc)),
Then_Statements =>
New_Copy_List_Tree (Tstats)));
----------------------------------
-- Protected procedure handling --
----------------------------------
-- Generate:
-- <dispatching-call>;
-- <triggering-statements>
ProtP_Stmts := New_Copy_List_Tree (Tstats);
Prepend_To (ProtP_Stmts, New_Copy_Tree (Ecall));
-- Generate:
-- S := Ada.Tags.Get_Offset_Index
-- (Ada.Tags.Tag (<object>), DT_Position (Call_Ent));
Conc_Typ_Stmts :=
New_List (Build_S_Assignment (Loc, S, Obj, Call_Ent));
-- Generate:
-- _Disp_Get_Prim_Op_Kind (<object>, S, C);
Append_To (Conc_Typ_Stmts,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of
(Find_Prim_Op (Etype (Etype (Obj)),
Name_uDisp_Get_Prim_Op_Kind),
Loc),
Parameter_Associations =>
New_List (
New_Copy_Tree (Obj),
New_Occurrence_Of (S, Loc),
New_Occurrence_Of (C, Loc))));
-- Generate:
-- if C = POK_Procedure_Entry then
-- ProtE_Stmts
-- elsif C = POK_Task_Entry then
-- TaskE_Stmts
-- else
-- ProtP_Stmts
-- end if;
Append_To (Conc_Typ_Stmts,
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_POK_Protected_Entry), Loc)),
Then_Statements =>
ProtE_Stmts,
Elsif_Parts =>
New_List (
Make_Elsif_Part (Loc,
Condition =>
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_POK_Task_Entry), Loc)),
Then_Statements =>
TaskE_Stmts)),
Else_Statements =>
ProtP_Stmts));
-- Generate:
-- <dispatching-call>;
-- <triggering-statements>
Lim_Typ_Stmts := New_Copy_List_Tree (Tstats);
Prepend_To (Lim_Typ_Stmts, New_Copy_Tree (Ecall));
-- Generate:
-- if K = Ada.Tags.TK_Limited_Tagged
-- or else K = Ada.Tags.TK_Tagged
-- then
-- Lim_Typ_Stmts
-- else
-- Conc_Typ_Stmts
-- end if;
Append_To (Stmts,
Make_Implicit_If_Statement (N,
Condition => Build_Dispatching_Tag_Check (K, N),
Then_Statements => Lim_Typ_Stmts,
Else_Statements => Conc_Typ_Stmts));
Rewrite (N,
Make_Block_Statement (Loc,
Declarations =>
Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Stmts)));
Analyze (N);
return;
-- Delay triggering statement processing
else
-- Add a Delay_Block object to the parameter list of the delay
-- procedure to form the parameter list of the Wait entry call.
Dblock_Ent := Make_Temporary (Loc, 'D');
Pdef := Entity (Name (Ecall));
if Is_RTE (Pdef, RO_CA_Delay_For) then
Enqueue_Call :=
New_Occurrence_Of (RTE (RE_Enqueue_Duration), Loc);
elsif Is_RTE (Pdef, RO_CA_Delay_Until) then
Enqueue_Call :=
New_Occurrence_Of (RTE (RE_Enqueue_Calendar), Loc);
else pragma Assert (Is_RTE (Pdef, RO_RT_Delay_Until));
Enqueue_Call := New_Occurrence_Of (RTE (RE_Enqueue_RT), Loc);
end if;
Append_To (Parameter_Associations (Ecall),
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Dblock_Ent, Loc),
Attribute_Name => Name_Unchecked_Access));
-- Create the inner block to protect the abortable part
Hdle := New_List (Build_Abort_Block_Handler (Loc));
Prepend_To (Astats, Build_Runtime_Call (Loc, RE_Abort_Undefer));
Abortable_Block :=
Make_Block_Statement (Loc,
Identifier => New_Occurrence_Of (Blk_Ent, Loc),
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Astats),
Has_Created_Identifier => True,
Is_Asynchronous_Call_Block => True);
-- Append call to if Enqueue (When, DB'Unchecked_Access) then
Rewrite (Ecall,
Make_Implicit_If_Statement (N,
Condition =>
Make_Function_Call (Loc,
Name => Enqueue_Call,
Parameter_Associations => Parameter_Associations (Ecall)),
Then_Statements =>
New_List (Make_Block_Statement (Loc,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier => Blk_Ent,
Label_Construct => Abortable_Block),
Abortable_Block),
Exception_Handlers => Hdle)))));
Stmts := New_List (Ecall);
-- Construct statement sequence for new block
Append_To (Stmts,
Make_Implicit_If_Statement (N,
Condition =>
Make_Function_Call (Loc,
Name => New_Occurrence_Of (
RTE (RE_Timed_Out), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Dblock_Ent, Loc),
Attribute_Name => Name_Unchecked_Access))),
Then_Statements => Tstats));
-- The result is the new block
Set_Entry_Cancel_Parameter (Blk_Ent, Dblock_Ent);
Rewrite (N,
Make_Block_Statement (Loc,
Declarations => New_List (
Make_Object_Declaration (Loc,
Defining_Identifier => Dblock_Ent,
Aliased_Present => True,
Object_Definition =>
New_Occurrence_Of (RTE (RE_Delay_Block), Loc))),
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Stmts)));
Analyze (N);
return;
end if;
else
N_Orig := N;
end if;
Extract_Entry (Ecall, Concval, Ename, Index);
Build_Simple_Entry_Call (Ecall, Concval, Ename, Index);
Stmts := Statements (Handled_Statement_Sequence (Ecall));
Decls := Declarations (Ecall);
if Is_Protected_Type (Etype (Concval)) then
-- Get the declarations of the block expanded from the entry call
Decl := First (Decls);
while Present (Decl)
and then (Nkind (Decl) /= N_Object_Declaration
or else not Is_RTE (Etype (Object_Definition (Decl)),
RE_Communication_Block))
loop
Next (Decl);
end loop;
pragma Assert (Present (Decl));
Cancel_Param := Defining_Identifier (Decl);
-- Change the mode of the Protected_Entry_Call call
-- Protected_Entry_Call (
-- Object => po._object'Access,
-- E => <entry index>;
-- Uninterpreted_Data => P'Address;
-- Mode => Asynchronous_Call;
-- Block => Bnn);
-- Skip assignments to temporaries created for in-out parameters
-- This makes unwarranted assumptions about the shape of the expanded
-- tree for the call, and should be cleaned up ???
Stmt := First (Stmts);
while Nkind (Stmt) /= N_Procedure_Call_Statement loop
Next (Stmt);
end loop;
Call := Stmt;
Param := First (Parameter_Associations (Call));
while Present (Param)
and then not Is_RTE (Etype (Param), RE_Call_Modes)
loop
Next (Param);
end loop;
pragma Assert (Present (Param));
Rewrite (Param, New_Occurrence_Of (RTE (RE_Asynchronous_Call), Loc));
Analyze (Param);
-- Append an if statement to execute the abortable part
-- Generate:
-- if Enqueued (Bnn) then
Append_To (Stmts,
Make_Implicit_If_Statement (N,
Condition =>
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Enqueued), Loc),
Parameter_Associations => New_List (
New_Occurrence_Of (Cancel_Param, Loc))),
Then_Statements => Astats));
Abortable_Block :=
Make_Block_Statement (Loc,
Identifier => New_Occurrence_Of (Blk_Ent, Loc),
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Statements => Stmts),
Has_Created_Identifier => True,
Is_Asynchronous_Call_Block => True);
Stmts := New_List (
Make_Block_Statement (Loc,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier => Blk_Ent,
Label_Construct => Abortable_Block),
Abortable_Block),
-- exception
Exception_Handlers => New_List (
Make_Implicit_Exception_Handler (Loc,
-- when Abort_Signal =>
-- null;
Exception_Choices =>
New_List (New_Occurrence_Of (Stand.Abort_Signal, Loc)),
Statements => New_List (Make_Null_Statement (Loc)))))),
-- if not Cancelled (Bnn) then
-- triggered statements
-- end if;
Make_Implicit_If_Statement (N,
Condition => Make_Op_Not (Loc,
Right_Opnd =>
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Cancelled), Loc),
Parameter_Associations => New_List (
New_Occurrence_Of (Cancel_Param, Loc)))),
Then_Statements => Tstats));
-- Asynchronous task entry call
else
if No (Decls) then
Decls := New_List;
end if;
B := Make_Defining_Identifier (Loc, Name_uB);
-- Insert declaration of B in declarations of existing block
Prepend_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => B,
Object_Definition =>
New_Occurrence_Of (Standard_Boolean, Loc)));
Cancel_Param := Make_Defining_Identifier (Loc, Name_uC);
-- Insert the declaration of C in the declarations of the existing
-- block. The variable is initialized to something (True or False,
-- does not matter) to prevent CodePeer from complaining about a
-- possible read of an uninitialized variable.
Prepend_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => Cancel_Param,
Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc),
Expression => New_Occurrence_Of (Standard_False, Loc),
Has_Init_Expression => True));
-- Remove and save the call to Call_Simple
Stmt := First (Stmts);
-- Skip assignments to temporaries created for in-out parameters.
-- This makes unwarranted assumptions about the shape of the expanded
-- tree for the call, and should be cleaned up ???
while Nkind (Stmt) /= N_Procedure_Call_Statement loop
Next (Stmt);
end loop;
Call := Stmt;
-- Create the inner block to protect the abortable part
Hdle := New_List (Build_Abort_Block_Handler (Loc));
Prepend_To (Astats, Build_Runtime_Call (Loc, RE_Abort_Undefer));
Abortable_Block :=
Make_Block_Statement (Loc,
Identifier => New_Occurrence_Of (Blk_Ent, Loc),
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Statements => Astats),
Has_Created_Identifier => True,
Is_Asynchronous_Call_Block => True);
Insert_After (Call,
Make_Block_Statement (Loc,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier => Blk_Ent,
Label_Construct => Abortable_Block),
Abortable_Block),
Exception_Handlers => Hdle)));
-- Create new call statement
Params := Parameter_Associations (Call);
Append_To (Params,
New_Occurrence_Of (RTE (RE_Asynchronous_Call), Loc));
Append_To (Params, New_Occurrence_Of (B, Loc));
Rewrite (Call,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Task_Entry_Call), Loc),
Parameter_Associations => Params));
-- Construct statement sequence for new block
Append_To (Stmts,
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Not (Loc, New_Occurrence_Of (Cancel_Param, Loc)),
Then_Statements => Tstats));
-- Protected the call against abort
Prepend_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Defer));
end if;
Set_Entry_Cancel_Parameter (Blk_Ent, Cancel_Param);
-- The result is the new block
Rewrite (N_Orig,
Make_Block_Statement (Loc,
Declarations => Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Stmts)));
Analyze (N_Orig);
end Expand_N_Asynchronous_Select;
-------------------------------------
-- Expand_N_Conditional_Entry_Call --
-------------------------------------
-- The conditional task entry call is converted to a call to
-- Task_Entry_Call:
-- declare
-- B : Boolean;
-- P : parms := (parm, parm, parm);
-- begin
-- Task_Entry_Call
-- (<acceptor-task>, -- Acceptor
-- <entry-index>, -- E
-- P'Address, -- Uninterpreted_Data
-- Conditional_Call, -- Mode
-- B); -- Rendezvous_Successful
-- parm := P.param;
-- parm := P.param;
-- ...
-- if B then
-- normal-statements
-- else
-- else-statements
-- end if;
-- end;
-- For a description of the use of P and the assignments after the call,
-- see Expand_N_Entry_Call_Statement. Note that the entry call of the
-- conditional entry call has already been expanded (by the Expand_N_Entry
-- _Call_Statement procedure) as follows:
-- declare
-- P : parms := (parm, parm, parm);
-- begin
-- ... info for in-out parameters
-- Call_Simple (acceptor-task, entry-index, P'Address);
-- parm := P.param;
-- parm := P.param;
-- ...
-- end;
-- so the task at hand is to convert the latter expansion into the former
-- The conditional protected entry call is converted to a call to
-- Protected_Entry_Call:
-- declare
-- P : parms := (parm, parm, parm);
-- Bnn : Communications_Block;
-- begin
-- Protected_Entry_Call
-- (po._object'Access, -- Object
-- <entry index>, -- E
-- P'Address, -- Uninterpreted_Data
-- Conditional_Call, -- Mode
-- Bnn); -- Block
-- parm := P.param;
-- parm := P.param;
-- ...
-- if Cancelled (Bnn) then
-- else-statements
-- else
-- normal-statements
-- end if;
-- end;
-- Ada 2005 (AI-345): A dispatching conditional entry call is converted
-- into:
-- declare
-- B : Boolean := False;
-- C : Ada.Tags.Prim_Op_Kind;
-- K : Ada.Tags.Tagged_Kind :=
-- Ada.Tags.Get_Tagged_Kind (Ada.Tags.Tag (<object>));
-- P : Parameters := (Param1 .. ParamN);
-- S : Integer;
-- begin
-- if K = Ada.Tags.TK_Limited_Tagged
-- or else K = Ada.Tags.TK_Tagged
-- then
-- <dispatching-call>;
-- <triggering-statements>
-- else
-- S :=
-- Ada.Tags.Get_Offset_Index
-- (Ada.Tags.Tag (<object>), DT_Position (<dispatching-call>));
-- _Disp_Conditional_Select (<object>, S, P'Address, C, B);
-- if C = POK_Protected_Entry
-- or else C = POK_Task_Entry
-- then
-- Param1 := P.Param1;
-- ...
-- ParamN := P.ParamN;
-- end if;
-- if B then
-- if C = POK_Procedure
-- or else C = POK_Protected_Procedure
-- or else C = POK_Task_Procedure
-- then
-- <dispatching-call>;
-- end if;
-- <triggering-statements>
-- else
-- <else-statements>
-- end if;
-- end if;
-- end;
procedure Expand_N_Conditional_Entry_Call (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Alt : constant Node_Id := Entry_Call_Alternative (N);
Blk : Node_Id := Entry_Call_Statement (Alt);
Actuals : List_Id;
Blk_Typ : Entity_Id;
Call : Node_Id;
Call_Ent : Entity_Id;
Conc_Typ_Stmts : List_Id;
Decl : Node_Id;
Decls : List_Id;
Formals : List_Id;
Lim_Typ_Stmts : List_Id;
N_Stats : List_Id;
Obj : Entity_Id;
Param : Node_Id;
Params : List_Id;
Stmt : Node_Id;
Stmts : List_Id;
Transient_Blk : Node_Id;
Unpack : List_Id;
B : Entity_Id; -- Call status flag
C : Entity_Id; -- Call kind
K : Entity_Id; -- Tagged kind
P : Entity_Id; -- Parameter block
S : Entity_Id; -- Primitive operation slot
begin
Process_Statements_For_Controlled_Objects (N);
if Ada_Version >= Ada_2005
and then Nkind (Blk) = N_Procedure_Call_Statement
then
Extract_Dispatching_Call (Blk, Call_Ent, Obj, Actuals, Formals);
Decls := New_List;
Stmts := New_List;
-- Call status flag processing, generate:
-- B : Boolean := False;
B := Build_B (Loc, Decls);
-- Call kind processing, generate:
-- C : Ada.Tags.Prim_Op_Kind;
C := Build_C (Loc, Decls);
-- Tagged kind processing, generate:
-- K : Ada.Tags.Tagged_Kind :=
-- Ada.Tags.Get_Tagged_Kind (Ada.Tags.Tag (<object>));
K := Build_K (Loc, Decls, Obj);
-- Parameter block processing
Blk_Typ := Build_Parameter_Block (Loc, Actuals, Formals, Decls);
P := Parameter_Block_Pack
(Loc, Blk_Typ, Actuals, Formals, Decls, Stmts);
-- Dispatch table slot processing, generate:
-- S : Integer;
S := Build_S (Loc, Decls);
-- Generate:
-- S := Ada.Tags.Get_Offset_Index
-- (Ada.Tags.Tag (<object>), DT_Position (Call_Ent));
Conc_Typ_Stmts :=
New_List (Build_S_Assignment (Loc, S, Obj, Call_Ent));
-- Generate:
-- _Disp_Conditional_Select (<object>, S, P'Address, C, B);
Append_To (Conc_Typ_Stmts,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of (
Find_Prim_Op (Etype (Etype (Obj)),
Name_uDisp_Conditional_Select),
Loc),
Parameter_Associations =>
New_List (
New_Copy_Tree (Obj), -- <object>
New_Occurrence_Of (S, Loc), -- S
Make_Attribute_Reference (Loc, -- P'Address
Prefix => New_Occurrence_Of (P, Loc),
Attribute_Name => Name_Address),
New_Occurrence_Of (C, Loc), -- C
New_Occurrence_Of (B, Loc)))); -- B
-- Generate:
-- if C = POK_Protected_Entry
-- or else C = POK_Task_Entry
-- then
-- Param1 := P.Param1;
-- ...
-- ParamN := P.ParamN;
-- end if;
Unpack := Parameter_Block_Unpack (Loc, P, Actuals, Formals);
-- Generate the if statement only when the packed parameters need
-- explicit assignments to their corresponding actuals.
if Present (Unpack) then
Append_To (Conc_Typ_Stmts,
Make_Implicit_If_Statement (N,
Condition =>
Make_Or_Else (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (
RE_POK_Protected_Entry), Loc)),
Right_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_POK_Task_Entry), Loc))),
Then_Statements => Unpack));
end if;
-- Generate:
-- if B then
-- if C = POK_Procedure
-- or else C = POK_Protected_Procedure
-- or else C = POK_Task_Procedure
-- then
-- <dispatching-call>
-- end if;
-- <normal-statements>
-- else
-- <else-statements>
-- end if;
N_Stats := New_Copy_Separate_List (Statements (Alt));
Prepend_To (N_Stats,
Make_Implicit_If_Statement (N,
Condition =>
Make_Or_Else (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_POK_Procedure), Loc)),
Right_Opnd =>
Make_Or_Else (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (
RE_POK_Protected_Procedure), Loc)),
Right_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (
RE_POK_Task_Procedure), Loc)))),
Then_Statements =>
New_List (Blk)));
Append_To (Conc_Typ_Stmts,
Make_Implicit_If_Statement (N,
Condition => New_Occurrence_Of (B, Loc),
Then_Statements => N_Stats,
Else_Statements => Else_Statements (N)));
-- Generate:
-- <dispatching-call>;
-- <triggering-statements>
Lim_Typ_Stmts := New_Copy_Separate_List (Statements (Alt));
Prepend_To (Lim_Typ_Stmts, New_Copy_Tree (Blk));
-- Generate:
-- if K = Ada.Tags.TK_Limited_Tagged
-- or else K = Ada.Tags.TK_Tagged
-- then
-- Lim_Typ_Stmts
-- else
-- Conc_Typ_Stmts
-- end if;
Append_To (Stmts,
Make_Implicit_If_Statement (N,
Condition => Build_Dispatching_Tag_Check (K, N),
Then_Statements => Lim_Typ_Stmts,
Else_Statements => Conc_Typ_Stmts));
Rewrite (N,
Make_Block_Statement (Loc,
Declarations =>
Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Stmts)));
-- As described above, the entry alternative is transformed into a
-- block that contains the gnulli call, and possibly assignment
-- statements for in-out parameters. The gnulli call may itself be
-- rewritten into a transient block if some unconstrained parameters
-- require it. We need to retrieve the call to complete its parameter
-- list.
else
Transient_Blk :=
First_Real_Statement (Handled_Statement_Sequence (Blk));
if Present (Transient_Blk)
and then Nkind (Transient_Blk) = N_Block_Statement
then
Blk := Transient_Blk;
end if;
Stmts := Statements (Handled_Statement_Sequence (Blk));
Stmt := First (Stmts);
while Nkind (Stmt) /= N_Procedure_Call_Statement loop
Next (Stmt);
end loop;
Call := Stmt;
Params := Parameter_Associations (Call);
if Is_RTE (Entity (Name (Call)), RE_Protected_Entry_Call) then
-- Substitute Conditional_Entry_Call for Simple_Call parameter
Param := First (Params);
while Present (Param)
and then not Is_RTE (Etype (Param), RE_Call_Modes)
loop
Next (Param);
end loop;
pragma Assert (Present (Param));
Rewrite (Param,
New_Occurrence_Of (RTE (RE_Conditional_Call), Loc));
Analyze (Param);
-- Find the Communication_Block parameter for the call to the
-- Cancelled function.
Decl := First (Declarations (Blk));
while Present (Decl)
and then not Is_RTE (Etype (Object_Definition (Decl)),
RE_Communication_Block)
loop
Next (Decl);
end loop;
-- Add an if statement to execute the else part if the call
-- does not succeed (as indicated by the Cancelled predicate).
Append_To (Stmts,
Make_Implicit_If_Statement (N,
Condition => Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Cancelled), Loc),
Parameter_Associations => New_List (
New_Occurrence_Of (Defining_Identifier (Decl), Loc))),
Then_Statements => Else_Statements (N),
Else_Statements => Statements (Alt)));
else
B := Make_Defining_Identifier (Loc, Name_uB);
-- Insert declaration of B in declarations of existing block
if No (Declarations (Blk)) then
Set_Declarations (Blk, New_List);
end if;
Prepend_To (Declarations (Blk),
Make_Object_Declaration (Loc,
Defining_Identifier => B,
Object_Definition =>
New_Occurrence_Of (Standard_Boolean, Loc)));
-- Create new call statement
Append_To (Params,
New_Occurrence_Of (RTE (RE_Conditional_Call), Loc));
Append_To (Params, New_Occurrence_Of (B, Loc));
Rewrite (Call,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Task_Entry_Call), Loc),
Parameter_Associations => Params));
-- Construct statement sequence for new block
Append_To (Stmts,
Make_Implicit_If_Statement (N,
Condition => New_Occurrence_Of (B, Loc),
Then_Statements => Statements (Alt),
Else_Statements => Else_Statements (N)));
end if;
-- The result is the new block
Rewrite (N,
Make_Block_Statement (Loc,
Declarations => Declarations (Blk),
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Stmts)));
end if;
Analyze (N);
Reset_Scopes_To (N, Entity (Identifier (N)));
end Expand_N_Conditional_Entry_Call;
---------------------------------------
-- Expand_N_Delay_Relative_Statement --
---------------------------------------
-- Delay statement is implemented as a procedure call to Delay_For
-- defined in Ada.Calendar.Delays in order to reduce the overhead of
-- simple delays imposed by the use of Protected Objects.
procedure Expand_N_Delay_Relative_Statement (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Proc : Entity_Id;
begin
-- Try to use Ada.Calendar.Delays.Delay_For if available.
if RTE_Available (RO_CA_Delay_For) then
Proc := RTE (RO_CA_Delay_For);
-- Otherwise, use System.Relative_Delays.Delay_For and emit an error
-- message if not available. This is the implementation used on
-- restricted platforms when Ada.Calendar is not available.
else
Proc := RTE (RO_RD_Delay_For);
end if;
Rewrite (N,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (Proc, Loc),
Parameter_Associations => New_List (Expression (N))));
Analyze (N);
end Expand_N_Delay_Relative_Statement;
------------------------------------
-- Expand_N_Delay_Until_Statement --
------------------------------------
-- Delay Until statement is implemented as a procedure call to
-- Delay_Until defined in Ada.Calendar.Delays and Ada.Real_Time.Delays.
procedure Expand_N_Delay_Until_Statement (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Typ : Entity_Id;
begin
if Is_RTE (Base_Type (Etype (Expression (N))), RO_CA_Time) then
Typ := RTE (RO_CA_Delay_Until);
else
Typ := RTE (RO_RT_Delay_Until);
end if;
Rewrite (N,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (Typ, Loc),
Parameter_Associations => New_List (Expression (N))));
Analyze (N);
end Expand_N_Delay_Until_Statement;
-------------------------
-- Expand_N_Entry_Body --
-------------------------
procedure Expand_N_Entry_Body (N : Node_Id) is
begin
-- Associate discriminals with the next protected operation body to be
-- expanded.
if Present (Next_Protected_Operation (N)) then
Set_Discriminals (Parent (Current_Scope));
end if;
end Expand_N_Entry_Body;
-----------------------------------
-- Expand_N_Entry_Call_Statement --
-----------------------------------
-- An entry call is expanded into GNARLI calls to implement a simple entry
-- call (see Build_Simple_Entry_Call).
procedure Expand_N_Entry_Call_Statement (N : Node_Id) is
Concval : Node_Id;
Ename : Node_Id;
Index : Node_Id;
begin
if No_Run_Time_Mode then
Error_Msg_CRT ("entry call", N);
return;
end if;
-- If this entry call is part of an asynchronous select, don't expand it
-- here; it will be expanded with the select statement. Don't expand
-- timed entry calls either, as they are translated into asynchronous
-- entry calls.
-- ??? This whole approach is questionable; it may be better to go back
-- to allowing the expansion to take place and then attempting to fix it
-- up in Expand_N_Asynchronous_Select. The tricky part is figuring out
-- whether the expanded call is on a task or protected entry.
if (Nkind (Parent (N)) /= N_Triggering_Alternative
or else N /= Triggering_Statement (Parent (N)))
and then (Nkind (Parent (N)) /= N_Entry_Call_Alternative
or else N /= Entry_Call_Statement (Parent (N))
or else Nkind (Parent (Parent (N))) /= N_Timed_Entry_Call)
then
Extract_Entry (N, Concval, Ename, Index);
Build_Simple_Entry_Call (N, Concval, Ename, Index);
end if;
end Expand_N_Entry_Call_Statement;
--------------------------------
-- Expand_N_Entry_Declaration --
--------------------------------
-- If there are parameters, then first, each of the formals is marked by
-- setting Is_Entry_Formal. Next a record type is built which is used to
-- hold the parameter values. The name of this record type is entryP where
-- entry is the name of the entry, with an additional corresponding access
-- type called entryPA. The record type has matching components for each
-- formal (the component names are the same as the formal names). For
-- elementary types, the component type matches the formal type. For
-- composite types, an access type is declared (with the name formalA)
-- which designates the formal type, and the type of the component is this
-- access type. Finally the Entry_Component of each formal is set to
-- reference the corresponding record component.
procedure Expand_N_Entry_Declaration (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Entry_Ent : constant Entity_Id := Defining_Identifier (N);
Components : List_Id;
Formal : Node_Id;
Ftype : Entity_Id;
Last_Decl : Node_Id;
Component : Entity_Id;
Ctype : Entity_Id;
Decl : Node_Id;
Rec_Ent : Entity_Id;
Acc_Ent : Entity_Id;
begin
Formal := First_Formal (Entry_Ent);
Last_Decl := N;
-- Most processing is done only if parameters are present
if Present (Formal) then
Components := New_List;
-- Loop through formals
while Present (Formal) loop
Set_Is_Entry_Formal (Formal);
Component :=
Make_Defining_Identifier (Sloc (Formal), Chars (Formal));
Set_Entry_Component (Formal, Component);
Set_Entry_Formal (Component, Formal);
Ftype := Etype (Formal);
-- Declare new access type and then append
Ctype := Make_Temporary (Loc, 'A');
Set_Is_Param_Block_Component_Type (Ctype);
Decl :=
Make_Full_Type_Declaration (Loc,
Defining_Identifier => Ctype,
Type_Definition =>
Make_Access_To_Object_Definition (Loc,
All_Present => True,
Constant_Present => Ekind (Formal) = E_In_Parameter,
Subtype_Indication => New_Occurrence_Of (Ftype, Loc)));
Insert_After (Last_Decl, Decl);
Last_Decl := Decl;
Append_To (Components,
Make_Component_Declaration (Loc,
Defining_Identifier => Component,
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication => New_Occurrence_Of (Ctype, Loc))));
Next_Formal_With_Extras (Formal);
end loop;
-- Create the Entry_Parameter_Record declaration
Rec_Ent := Make_Temporary (Loc, 'P');
Decl :=
Make_Full_Type_Declaration (Loc,
Defining_Identifier => Rec_Ent,
Type_Definition =>
Make_Record_Definition (Loc,
Component_List =>
Make_Component_List (Loc,
Component_Items => Components)));
Insert_After (Last_Decl, Decl);
Last_Decl := Decl;
-- Construct and link in the corresponding access type
Acc_Ent := Make_Temporary (Loc, 'A');
Set_Entry_Parameters_Type (Entry_Ent, Acc_Ent);
Decl :=
Make_Full_Type_Declaration (Loc,
Defining_Identifier => Acc_Ent,
Type_Definition =>
Make_Access_To_Object_Definition (Loc,
All_Present => True,
Subtype_Indication => New_Occurrence_Of (Rec_Ent, Loc)));
Insert_After (Last_Decl, Decl);
end if;
end Expand_N_Entry_Declaration;
-----------------------------
-- Expand_N_Protected_Body --
-----------------------------
-- Protected bodies are expanded to the completion of the subprograms
-- created for the corresponding protected type. These are a protected and
-- unprotected version of each protected subprogram in the object, a
-- function to calculate each entry barrier, and a procedure to execute the
-- sequence of statements of each protected entry body. For example, for
-- protected type ptype:
-- function entB
-- (O : System.Address;
-- E : Protected_Entry_Index)
-- return Boolean
-- is
-- <discriminant renamings>
-- <private object renamings>
-- begin
-- return <barrier expression>;
-- end entB;
-- procedure pprocN (_object : in out poV;...) is
-- <discriminant renamings>
-- <private object renamings>
-- begin
-- <sequence of statements>
-- end pprocN;
-- procedure pprocP (_object : in out poV;...) is
-- procedure _clean is
-- Pn : Boolean;
-- begin
-- ptypeS (_object, Pn);
-- Unlock (_object._object'Access);
-- Abort_Undefer.all;
-- end _clean;
-- begin
-- Abort_Defer.all;
-- Lock (_object._object'Access);
-- pprocN (_object;...);
-- at end
-- _clean;
-- end pproc;
-- function pfuncN (_object : poV;...) return Return_Type is
-- <discriminant renamings>
-- <private object renamings>
-- begin
-- <sequence of statements>
-- end pfuncN;
-- function pfuncP (_object : poV) return Return_Type is
-- procedure _clean is
-- begin
-- Unlock (_object._object'Access);
-- Abort_Undefer.all;
-- end _clean;
-- begin
-- Abort_Defer.all;
-- Lock (_object._object'Access);
-- return pfuncN (_object);
-- at end
-- _clean;
-- end pfunc;
-- procedure entE
-- (O : System.Address;
-- P : System.Address;
-- E : Protected_Entry_Index)
-- is
-- <discriminant renamings>
-- <private object renamings>
-- type poVP is access poV;
-- _Object : ptVP := ptVP!(O);
-- begin
-- begin
-- <statement sequence>
-- Complete_Entry_Body (_Object._Object);
-- exception
-- when all others =>
-- Exceptional_Complete_Entry_Body (
-- _Object._Object, Get_GNAT_Exception);
-- end;
-- end entE;
-- The type poV is the record created for the protected type to hold
-- the state of the protected object.
procedure Expand_N_Protected_Body (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Pid : constant Entity_Id := Corresponding_Spec (N);
Lock_Free_Active : constant Boolean := Uses_Lock_Free (Pid);
-- This flag indicates whether the lock free implementation is active
Current_Node : Node_Id;
Disp_Op_Body : Node_Id;
New_Op_Body : Node_Id;
Op_Body : Node_Id;
Op_Decl : Node_Id;
Op_Id : Entity_Id;
function Build_Dispatching_Subprogram_Body
(N : Node_Id;
Pid : Node_Id;
Prot_Bod : Node_Id) return Node_Id;
-- Build a dispatching version of the protected subprogram body. The
-- newly generated subprogram contains a call to the original protected
-- body. The following code is generated:
--
-- function <protected-function-name> (Param1 .. ParamN) return
-- <return-type> is
-- begin
-- return <protected-function-name>P (Param1 .. ParamN);
-- end <protected-function-name>;
--
-- or
--
-- procedure <protected-procedure-name> (Param1 .. ParamN) is
-- begin
-- <protected-procedure-name>P (Param1 .. ParamN);
-- end <protected-procedure-name>
---------------------------------------
-- Build_Dispatching_Subprogram_Body --
---------------------------------------
function Build_Dispatching_Subprogram_Body
(N : Node_Id;
Pid : Node_Id;
Prot_Bod : Node_Id) return Node_Id
is
Loc : constant Source_Ptr := Sloc (N);
Actuals : List_Id;
Formal : Node_Id;
Spec : Node_Id;
Stmts : List_Id;
begin
-- Generate a specification without a letter suffix in order to
-- override an interface function or procedure.
Spec := Build_Protected_Sub_Specification (N, Pid, Dispatching_Mode);
-- The formal parameters become the actuals of the protected function
-- or procedure call.
Actuals := New_List;
Formal := First (Parameter_Specifications (Spec));
while Present (Formal) loop
Append_To (Actuals,
Make_Identifier (Loc, Chars (Defining_Identifier (Formal))));
Next (Formal);
end loop;
if Nkind (Spec) = N_Procedure_Specification then
Stmts :=
New_List (
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of (Corresponding_Spec (Prot_Bod), Loc),
Parameter_Associations => Actuals));
else
pragma Assert (Nkind (Spec) = N_Function_Specification);
Stmts :=
New_List (
Make_Simple_Return_Statement (Loc,
Expression =>
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (Corresponding_Spec (Prot_Bod), Loc),
Parameter_Associations => Actuals)));
end if;
return
Make_Subprogram_Body (Loc,
Declarations => Empty_List,
Specification => Spec,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Stmts));
end Build_Dispatching_Subprogram_Body;
-- Start of processing for Expand_N_Protected_Body
begin
if No_Run_Time_Mode then
Error_Msg_CRT ("protected body", N);
return;
end if;
-- This is the proper body corresponding to a stub. The declarations
-- must be inserted at the point of the stub, which in turn is in the
-- declarative part of the parent unit.
if Nkind (Parent (N)) = N_Subunit then
Current_Node := Corresponding_Stub (Parent (N));
else
Current_Node := N;
end if;
Op_Body := First (Declarations (N));
-- The protected body is replaced with the bodies of its protected
-- operations, and the declarations for internal objects that may
-- have been created for entry family bounds.
Rewrite (N, Make_Null_Statement (Sloc (N)));
Analyze (N);
while Present (Op_Body) loop
case Nkind (Op_Body) is
when N_Subprogram_Declaration =>
null;
when N_Subprogram_Body =>
-- Do not create bodies for eliminated operations
if not Is_Eliminated (Defining_Entity (Op_Body))
and then not Is_Eliminated (Corresponding_Spec (Op_Body))
then
if Lock_Free_Active then
New_Op_Body :=
Build_Lock_Free_Unprotected_Subprogram_Body
(Op_Body, Pid);
else
New_Op_Body :=
Build_Unprotected_Subprogram_Body (Op_Body, Pid);
end if;
Insert_After (Current_Node, New_Op_Body);
Current_Node := New_Op_Body;
Analyze (New_Op_Body);
-- When the original protected body has nested subprograms,
-- the new body also has them, so set the flag accordingly
-- and reset the scopes of the top-level nested subprograms
-- and other declaration entities so that they now refer to
-- the new body's entity. (It would preferable to do this
-- within Build_Protected_Sub_Specification, which is called
-- from Build_Unprotected_Subprogram_Body, but the needed
-- subprogram entity isn't available via Corresponding_Spec
-- until after the above Analyze call.)
if Has_Nested_Subprogram (Corresponding_Spec (Op_Body)) then
Set_Has_Nested_Subprogram
(Corresponding_Spec (New_Op_Body));
Reset_Scopes_To
(New_Op_Body, Corresponding_Spec (New_Op_Body));
end if;
-- Build the corresponding protected operation. This is
-- needed only if this is a public or private operation of
-- the type.
-- Why do we need to test for Corresponding_Spec being
-- present here when it's assumed to be set further above
-- in the Is_Eliminated test???
if Present (Corresponding_Spec (Op_Body)) then
Op_Decl :=
Unit_Declaration_Node (Corresponding_Spec (Op_Body));
if Nkind (Parent (Op_Decl)) = N_Protected_Definition then
if Lock_Free_Active then
New_Op_Body :=
Build_Lock_Free_Protected_Subprogram_Body
(Op_Body, Pid, Specification (New_Op_Body));
else
New_Op_Body :=
Build_Protected_Subprogram_Body (
Op_Body, Pid, Specification (New_Op_Body));
end if;
Insert_After (Current_Node, New_Op_Body);
Analyze (New_Op_Body);
Current_Node := New_Op_Body;
-- Generate an overriding primitive operation body for
-- this subprogram if the protected type implements
-- an interface.
if Ada_Version >= Ada_2005
and then Present (Interfaces (
Corresponding_Record_Type (Pid)))
then
Disp_Op_Body :=
Build_Dispatching_Subprogram_Body (
Op_Body, Pid, New_Op_Body);
Insert_After (Current_Node, Disp_Op_Body);
Analyze (Disp_Op_Body);
Current_Node := Disp_Op_Body;
end if;
end if;
end if;
end if;
when N_Entry_Body =>
Op_Id := Defining_Identifier (Op_Body);
New_Op_Body := Build_Protected_Entry (Op_Body, Op_Id, Pid);
Insert_After (Current_Node, New_Op_Body);
Current_Node := New_Op_Body;
Analyze (New_Op_Body);
when N_Implicit_Label_Declaration =>
null;
when N_Call_Marker
| N_Itype_Reference
=>
New_Op_Body := New_Copy (Op_Body);
Insert_After (Current_Node, New_Op_Body);
Current_Node := New_Op_Body;
when N_Freeze_Entity =>
New_Op_Body := New_Copy (Op_Body);
if Present (Entity (Op_Body))
and then Freeze_Node (Entity (Op_Body)) = Op_Body
then
Set_Freeze_Node (Entity (Op_Body), New_Op_Body);
end if;
Insert_After (Current_Node, New_Op_Body);
Current_Node := New_Op_Body;
Analyze (New_Op_Body);
when N_Pragma =>
New_Op_Body := New_Copy (Op_Body);
Insert_After (Current_Node, New_Op_Body);
Current_Node := New_Op_Body;
Analyze (New_Op_Body);
when N_Object_Declaration =>
pragma Assert (not Comes_From_Source (Op_Body));
New_Op_Body := New_Copy (Op_Body);
Insert_After (Current_Node, New_Op_Body);
Current_Node := New_Op_Body;
Analyze (New_Op_Body);
when others =>
raise Program_Error;
end case;
Next (Op_Body);
end loop;
-- Finally, create the body of the function that maps an entry index
-- into the corresponding body index, except when there is no entry, or
-- in a Ravenscar-like profile.
if Corresponding_Runtime_Package (Pid) =
System_Tasking_Protected_Objects_Entries
then
New_Op_Body := Build_Find_Body_Index (Pid);
Insert_After (Current_Node, New_Op_Body);
Current_Node := New_Op_Body;
Analyze (New_Op_Body);
end if;
-- Ada 2005 (AI-345): Construct the primitive wrapper bodies after the
-- protected body. At this point all wrapper specs have been created,
-- frozen and included in the dispatch table for the protected type.
if Ada_Version >= Ada_2005 then
Build_Wrapper_Bodies (Loc, Pid, Current_Node);
end if;
end Expand_N_Protected_Body;
-----------------------------------------
-- Expand_N_Protected_Type_Declaration --
-----------------------------------------
-- First we create a corresponding record type declaration used to
-- represent values of this protected type.
-- The general form of this type declaration is
-- type poV (discriminants) is record
-- _Object : aliased <kind>Protection
-- [(<entry count> [, <handler count>])];
-- [entry_family : array (bounds) of Void;]
-- <private data fields>
-- end record;
-- The discriminants are present only if the corresponding protected type
-- has discriminants, and they exactly mirror the protected type
-- discriminants. The private data fields similarly mirror the private
-- declarations of the protected type.
-- The Object field is always present. It contains RTS specific data used
-- to control the protected object. It is declared as Aliased so that it
-- can be passed as a pointer to the RTS. This allows the protected record
-- to be referenced within RTS data structures. An appropriate Protection
-- type and discriminant are generated.
-- The Service field is present for protected objects with entries. It
-- contains sufficient information to allow the entry service procedure for
-- this object to be called when the object is not known till runtime.
-- One entry_family component is present for each entry family in the
-- task definition (see Expand_N_Task_Type_Declaration).
-- When a protected object is declared, an instance of the protected type
-- value record is created. The elaboration of this declaration creates the
-- correct bounds for the entry families, and also evaluates the priority
-- expression if needed. The initialization routine for the protected type
-- itself then calls Initialize_Protection with appropriate parameters to
-- initialize the value of the Task_Id field. Install_Handlers may be also
-- called if a pragma Attach_Handler applies.
-- Note: this record is passed to the subprograms created by the expansion
-- of protected subprograms and entries. It is an in parameter to protected
-- functions and an in out parameter to procedures and entry bodies. The
-- Entity_Id for this created record type is placed in the
-- Corresponding_Record_Type field of the associated protected type entity.
-- Next we create a procedure specifications for protected subprograms and
-- entry bodies. For each protected subprograms two subprograms are
-- created, an unprotected and a protected version. The unprotected version
-- is called from within other operations of the same protected object.
-- We also build the call to register the procedure if a pragma
-- Interrupt_Handler applies.
-- A single subprogram is created to service all entry bodies; it has an
-- additional boolean out parameter indicating that the previous entry call
-- made by the current task was serviced immediately, i.e. not by proxy.
-- The O parameter contains a pointer to a record object of the type
-- described above. An untyped interface is used here to allow this
-- procedure to be called in places where the type of the object to be
-- serviced is not known. This must be done, for example, when a call that
-- may have been requeued is cancelled; the corresponding object must be
-- serviced, but which object that is not known till runtime.
-- procedure ptypeS
-- (O : System.Address; P : out Boolean);
-- procedure pprocN (_object : in out poV);
-- procedure pproc (_object : in out poV);
-- function pfuncN (_object : poV);
-- function pfunc (_object : poV);
-- ...
-- Note that this must come after the record type declaration, since
-- the specs refer to this type.
procedure Expand_N_Protected_Type_Declaration (N : Node_Id) is
Discr_Map : constant Elist_Id := New_Elmt_List;
Loc : constant Source_Ptr := Sloc (N);
Prot_Typ : constant Entity_Id := Defining_Identifier (N);
Lock_Free_Active : constant Boolean := Uses_Lock_Free (Prot_Typ);
-- This flag indicates whether the lock free implementation is active
Pdef : constant Node_Id := Protected_Definition (N);
-- This contains two lists; one for visible and one for private decls
Current_Node : Node_Id := N;
E_Count : Int;
Entries_Aggr : Node_Id;
Rec_Decl : Node_Id;
Rec_Id : Entity_Id;
procedure Check_Inlining (Subp : Entity_Id);
-- If the original operation has a pragma Inline, propagate the flag
-- to the internal body, for possible inlining later on. The source
-- operation is invisible to the back-end and is never actually called.
procedure Expand_Entry_Declaration (Decl : Node_Id);
-- Create the entry barrier and the procedure body for entry declaration
-- Decl. All generated subprograms are added to Entry_Bodies_Array.
function Static_Component_Size (Comp : Entity_Id) return Boolean;
-- When compiling under the Ravenscar profile, private components must
-- have a static size, or else a protected object will require heap
-- allocation, violating the corresponding restriction. It is preferable
-- to make this check here, because it provides a better error message
-- than the back-end, which refers to the object as a whole.
procedure Register_Handler;
-- For a protected operation that is an interrupt handler, add the
-- freeze action that will register it as such.
procedure Replace_Access_Definition (Comp : Node_Id);
-- If a private component of the type is an access to itself, this
-- is not a reference to the current instance, but an access type out
-- of which one might construct a list. If such a component exists, we
-- create an incomplete type for the equivalent record type, and
-- a named access type for it, that replaces the access definition
-- of the original component. This is similar to what is done for
-- records in Check_Anonymous_Access_Components, but simpler, because
-- the corresponding record type has no previous declaration.
-- This needs to be done only once, even if there are several such
-- access components. The following entity stores the constructed
-- access type.
Acc_T : Entity_Id := Empty;
--------------------
-- Check_Inlining --
--------------------
procedure Check_Inlining (Subp : Entity_Id) is
begin
if Is_Inlined (Subp) then
Set_Is_Inlined (Protected_Body_Subprogram (Subp));
Set_Is_Inlined (Subp, False);
end if;
if Has_Pragma_No_Inline (Subp) then
Set_Has_Pragma_No_Inline (Protected_Body_Subprogram (Subp));
end if;
end Check_Inlining;
---------------------------
-- Static_Component_Size --
---------------------------
function Static_Component_Size (Comp : Entity_Id) return Boolean is
Typ : constant Entity_Id := Etype (Comp);
C : Entity_Id;
begin
if Is_Scalar_Type (Typ) then
return True;
elsif Is_Array_Type (Typ) then
return Compile_Time_Known_Bounds (Typ);
elsif Is_Record_Type (Typ) then
C := First_Component (Typ);
while Present (C) loop
if not Static_Component_Size (C) then
return False;
end if;
Next_Component (C);
end loop;
return True;
-- Any other type will be checked by the back-end
else
return True;
end if;
end Static_Component_Size;
------------------------------
-- Expand_Entry_Declaration --
------------------------------
procedure Expand_Entry_Declaration (Decl : Node_Id) is
Ent_Id : constant Entity_Id := Defining_Entity (Decl);
Bar_Id : Entity_Id;
Bod_Id : Entity_Id;
Subp : Node_Id;
begin
E_Count := E_Count + 1;
-- Create the protected body subprogram
Bod_Id :=
Make_Defining_Identifier (Loc,
Chars => Build_Selected_Name (Prot_Typ, Ent_Id, 'E'));
Set_Protected_Body_Subprogram (Ent_Id, Bod_Id);
Subp :=
Make_Subprogram_Declaration (Loc,
Specification =>
Build_Protected_Entry_Specification (Loc, Bod_Id, Ent_Id));
Insert_After (Current_Node, Subp);
Current_Node := Subp;
Analyze (Subp);
-- Build a wrapper procedure to handle contract cases, preconditions,
-- and postconditions.
Build_Contract_Wrapper (Ent_Id, N);
-- Create the barrier function
Bar_Id :=
Make_Defining_Identifier (Loc,
Chars => Build_Selected_Name (Prot_Typ, Ent_Id, 'B'));
Set_Barrier_Function (Ent_Id, Bar_Id);
Subp :=
Make_Subprogram_Declaration (Loc,
Specification =>
Build_Barrier_Function_Specification (Loc, Bar_Id));
Set_Is_Entry_Barrier_Function (Subp);
Insert_After (Current_Node, Subp);
Current_Node := Subp;
Analyze (Subp);
Set_Protected_Body_Subprogram (Bar_Id, Bar_Id);
Set_Scope (Bar_Id, Scope (Ent_Id));
-- Collect pointers to the protected subprogram and the barrier
-- of the current entry, for insertion into Entry_Bodies_Array.
Append_To (Expressions (Entries_Aggr),
Make_Aggregate (Loc,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Bar_Id, Loc),
Attribute_Name => Name_Unrestricted_Access),
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Bod_Id, Loc),
Attribute_Name => Name_Unrestricted_Access))));
end Expand_Entry_Declaration;
----------------------
-- Register_Handler --
----------------------
procedure Register_Handler is
-- All semantic checks already done in Sem_Prag
Prot_Proc : constant Entity_Id :=
Defining_Unit_Name (Specification (Current_Node));
Proc_Address : constant Node_Id :=
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Prot_Proc, Loc),
Attribute_Name => Name_Address);
RTS_Call : constant Entity_Id :=
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of
(RTE (RE_Register_Interrupt_Handler), Loc),
Parameter_Associations => New_List (Proc_Address));
begin
Append_Freeze_Action (Prot_Proc, RTS_Call);
end Register_Handler;
-------------------------------
-- Replace_Access_Definition --
-------------------------------
procedure Replace_Access_Definition (Comp : Node_Id) is
Loc : constant Source_Ptr := Sloc (Comp);
Inc_T : Node_Id;
Inc_D : Node_Id;
Acc_Def : Node_Id;
Acc_D : Node_Id;
begin
if No (Acc_T) then
Inc_T := Make_Defining_Identifier (Loc, Chars (Rec_Id));
Inc_D := Make_Incomplete_Type_Declaration (Loc, Inc_T);
Acc_T := Make_Temporary (Loc, 'S');
Acc_Def :=
Make_Access_To_Object_Definition (Loc,
Subtype_Indication => New_Occurrence_Of (Inc_T, Loc));
Acc_D :=
Make_Full_Type_Declaration (Loc,
Defining_Identifier => Acc_T,
Type_Definition => Acc_Def);
Insert_Before (Rec_Decl, Inc_D);
Analyze (Inc_D);
Insert_Before (Rec_Decl, Acc_D);
Analyze (Acc_D);
end if;
Set_Access_Definition (Comp, Empty);
Set_Subtype_Indication (Comp, New_Occurrence_Of (Acc_T, Loc));
end Replace_Access_Definition;
-- Local variables
Body_Arr : Node_Id;
Body_Id : Entity_Id;
Cdecls : List_Id;
Comp : Node_Id;
Expr : Node_Id;
New_Priv : Node_Id;
Obj_Def : Node_Id;
Object_Comp : Node_Id;
Priv : Node_Id;
Sub : Node_Id;
-- Start of processing for Expand_N_Protected_Type_Declaration
begin
if Present (Corresponding_Record_Type (Prot_Typ)) then
return;
else
Rec_Decl := Build_Corresponding_Record (N, Prot_Typ, Loc);
Rec_Id := Defining_Identifier (Rec_Decl);
end if;
Cdecls := Component_Items (Component_List (Type_Definition (Rec_Decl)));
Qualify_Entity_Names (N);
-- If the type has discriminants, their occurrences in the declaration
-- have been replaced by the corresponding discriminals. For components
-- that are constrained by discriminants, their homologues in the
-- corresponding record type must refer to the discriminants of that
-- record, so we must apply a new renaming to subtypes_indications:
-- protected discriminant => discriminal => record discriminant
-- This replacement is not applied to default expressions, for which
-- the discriminal is correct.
if Has_Discriminants (Prot_Typ) then
declare
Disc : Entity_Id;
Decl : Node_Id;
begin
Disc := First_Discriminant (Prot_Typ);
Decl := First (Discriminant_Specifications (Rec_Decl));
while Present (Disc) loop
Append_Elmt (Discriminal (Disc), Discr_Map);
Append_Elmt (Defining_Identifier (Decl), Discr_Map);
Next_Discriminant (Disc);
Next (Decl);
end loop;
end;
end if;
-- Fill in the component declarations
-- Add components for entry families. For each entry family, create an
-- anonymous type declaration with the same size, and analyze the type.
Collect_Entry_Families (Loc, Cdecls, Current_Node, Prot_Typ);
pragma Assert (Present (Pdef));
Insert_After (Current_Node, Rec_Decl);
Current_Node := Rec_Decl;
-- Add private field components
if Present (Private_Declarations (Pdef)) then
Priv := First (Private_Declarations (Pdef));
while Present (Priv) loop
if Nkind (Priv) = N_Component_Declaration then
if not Static_Component_Size (Defining_Identifier (Priv)) then
-- When compiling for a restricted profile, the private
-- components must have a static size. If not, this is an
-- error for a single protected declaration, and rates a
-- warning on a protected type declaration.
if not Comes_From_Source (Prot_Typ) then
-- It's ok to be checking this restriction at expansion
-- time, because this is only for the restricted profile,
-- which is not subject to strict RM conformance, so it
-- is OK to miss this check in -gnatc mode.
Check_Restriction (No_Implicit_Heap_Allocations, Priv);
Check_Restriction
(No_Implicit_Protected_Object_Allocations, Priv);
elsif Restriction_Active (No_Implicit_Heap_Allocations) then
if not Discriminated_Size (Defining_Identifier (Priv))
then
-- Any object of the type will be non-static
Error_Msg_N ("component has non-static size??", Priv);
Error_Msg_NE
("\creation of protected object of type& will "
& "violate restriction "
& "No_Implicit_Heap_Allocations??", Priv, Prot_Typ);
else
-- Object will be non-static if discriminants are
Error_Msg_NE
("creation of protected object of type& with "
& "non-static discriminants will violate "
& "restriction No_Implicit_Heap_Allocations??",
Priv, Prot_Typ);
end if;
-- Likewise for No_Implicit_Protected_Object_Allocations
elsif Restriction_Active
(No_Implicit_Protected_Object_Allocations)
then
if not Discriminated_Size (Defining_Identifier (Priv))
then
-- Any object of the type will be non-static
Error_Msg_N ("component has non-static size??", Priv);
Error_Msg_NE
("\creation of protected object of type& will "
& "violate restriction "
& "No_Implicit_Protected_Object_Allocations??",
Priv, Prot_Typ);
else
-- Object will be non-static if discriminants are
Error_Msg_NE
("creation of protected object of type& with "
& "non-static discriminants will violate "
& "restriction "
& "No_Implicit_Protected_Object_Allocations??",
Priv, Prot_Typ);
end if;
end if;
end if;
-- The component definition consists of a subtype indication,
-- or (in Ada 2005) an access definition. Make a copy of the
-- proper definition.
declare
Old_Comp : constant Node_Id := Component_Definition (Priv);
Oent : constant Entity_Id := Defining_Identifier (Priv);
Nent : constant Entity_Id :=
Make_Defining_Identifier (Sloc (Oent),
Chars => Chars (Oent));
New_Comp : Node_Id;
begin
if Present (Subtype_Indication (Old_Comp)) then
New_Comp :=
Make_Component_Definition (Sloc (Oent),
Aliased_Present => False,
Subtype_Indication =>
New_Copy_Tree
(Subtype_Indication (Old_Comp), Discr_Map));
else
New_Comp :=
Make_Component_Definition (Sloc (Oent),
Aliased_Present => False,
Access_Definition =>
New_Copy_Tree
(Access_Definition (Old_Comp), Discr_Map));
-- A self-reference in the private part becomes a
-- self-reference to the corresponding record.
if Entity (Subtype_Mark (Access_Definition (New_Comp)))
= Prot_Typ
then
Replace_Access_Definition (New_Comp);
end if;
end if;
New_Priv :=
Make_Component_Declaration (Loc,
Defining_Identifier => Nent,
Component_Definition => New_Comp,
Expression => Expression (Priv));
Set_Has_Per_Object_Constraint (Nent,
Has_Per_Object_Constraint (Oent));
Append_To (Cdecls, New_Priv);
end;
elsif Nkind (Priv) = N_Subprogram_Declaration then
-- Make the unprotected version of the subprogram available
-- for expansion of intra object calls. There is need for
-- a protected version only if the subprogram is an interrupt
-- handler, otherwise this operation can only be called from
-- within the body.
Sub :=
Make_Subprogram_Declaration (Loc,
Specification =>
Build_Protected_Sub_Specification
(Priv, Prot_Typ, Unprotected_Mode));
Insert_After (Current_Node, Sub);
Analyze (Sub);
Set_Protected_Body_Subprogram
(Defining_Unit_Name (Specification (Priv)),
Defining_Unit_Name (Specification (Sub)));
Check_Inlining (Defining_Unit_Name (Specification (Priv)));
Current_Node := Sub;
Sub :=
Make_Subprogram_Declaration (Loc,
Specification =>
Build_Protected_Sub_Specification
(Priv, Prot_Typ, Protected_Mode));
Insert_After (Current_Node, Sub);
Analyze (Sub);
Current_Node := Sub;
if Is_Interrupt_Handler
(Defining_Unit_Name (Specification (Priv)))
then
if not Restricted_Profile then
Register_Handler;
end if;
end if;
end if;
Next (Priv);
end loop;
end if;
-- Except for the lock-free implementation, append the _Object field
-- with the right type to the component list. We need to compute the
-- number of entries, and in some cases the number of Attach_Handler
-- pragmas.
if not Lock_Free_Active then
declare
Entry_Count_Expr : constant Node_Id :=
Build_Entry_Count_Expression
(Prot_Typ, Cdecls, Loc);
Num_Attach_Handler : Nat := 0;
Protection_Subtype : Node_Id;
Ritem : Node_Id;
begin
if Has_Attach_Handler (Prot_Typ) then
Ritem := First_Rep_Item (Prot_Typ);
while Present (Ritem) loop
if Nkind (Ritem) = N_Pragma
and then Pragma_Name (Ritem) = Name_Attach_Handler
then
Num_Attach_Handler := Num_Attach_Handler + 1;
end if;
Next_Rep_Item (Ritem);
end loop;
end if;
-- Determine the proper protection type. There are two special
-- cases: 1) when the protected type has dynamic interrupt
-- handlers, and 2) when it has static handlers and we use a
-- restricted profile.
if Has_Attach_Handler (Prot_Typ)
and then not Restricted_Profile
then
Protection_Subtype :=
Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of
(RTE (RE_Static_Interrupt_Protection), Loc),
Constraint =>
Make_Index_Or_Discriminant_Constraint (Loc,
Constraints => New_List (
Entry_Count_Expr,
Make_Integer_Literal (Loc, Num_Attach_Handler))));
elsif Has_Interrupt_Handler (Prot_Typ)
and then not Restriction_Active (No_Dynamic_Attachment)
then
Protection_Subtype :=
Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of
(RTE (RE_Dynamic_Interrupt_Protection), Loc),
Constraint =>
Make_Index_Or_Discriminant_Constraint (Loc,
Constraints => New_List (Entry_Count_Expr)));
else
case Corresponding_Runtime_Package (Prot_Typ) is
when System_Tasking_Protected_Objects_Entries =>
Protection_Subtype :=
Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of
(RTE (RE_Protection_Entries), Loc),
Constraint =>
Make_Index_Or_Discriminant_Constraint (Loc,
Constraints => New_List (Entry_Count_Expr)));
when System_Tasking_Protected_Objects_Single_Entry =>
Protection_Subtype :=
New_Occurrence_Of (RTE (RE_Protection_Entry), Loc);
when System_Tasking_Protected_Objects =>
Protection_Subtype :=
New_Occurrence_Of (RTE (RE_Protection), Loc);
when others =>
raise Program_Error;
end case;
end if;
Object_Comp :=
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uObject),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => True,
Subtype_Indication => Protection_Subtype));
end;
-- Put the _Object component after the private component so that it
-- be finalized early as required by 9.4 (20)
Append_To (Cdecls, Object_Comp);
end if;
-- Analyze the record declaration immediately after construction,
-- because the initialization procedure is needed for single object
-- declarations before the next entity is analyzed (the freeze call
-- that generates this initialization procedure is found below).
Analyze (Rec_Decl, Suppress => All_Checks);
-- Ada 2005 (AI-345): Construct the primitive entry wrappers before
-- the corresponding record is frozen. If any wrappers are generated,
-- Current_Node is updated accordingly.
if Ada_Version >= Ada_2005 then
Build_Wrapper_Specs (Loc, Prot_Typ, Current_Node);
end if;
-- Collect pointers to entry bodies and their barriers, to be placed
-- in the Entry_Bodies_Array for the type. For each entry/family we
-- add an expression to the aggregate which is the initial value of
-- this array. The array is declared after all protected subprograms.
if Has_Entries (Prot_Typ) then
Entries_Aggr := Make_Aggregate (Loc, Expressions => New_List);
else
Entries_Aggr := Empty;
end if;
-- Build two new procedure specifications for each protected subprogram;
-- one to call from outside the object and one to call from inside.
-- Build a barrier function and an entry body action procedure
-- specification for each protected entry. Initialize the entry body
-- array. If subprogram is flagged as eliminated, do not generate any
-- internal operations.
E_Count := 0;
Comp := First (Visible_Declarations (Pdef));
while Present (Comp) loop
if Nkind (Comp) = N_Subprogram_Declaration then
Sub :=
Make_Subprogram_Declaration (Loc,
Specification =>
Build_Protected_Sub_Specification
(Comp, Prot_Typ, Unprotected_Mode));
Insert_After (Current_Node, Sub);
Analyze (Sub);
Set_Protected_Body_Subprogram
(Defining_Unit_Name (Specification (Comp)),
Defining_Unit_Name (Specification (Sub)));
Check_Inlining (Defining_Unit_Name (Specification (Comp)));
-- Make the protected version of the subprogram available for
-- expansion of external calls.
Current_Node := Sub;
Sub :=
Make_Subprogram_Declaration (Loc,
Specification =>
Build_Protected_Sub_Specification
(Comp, Prot_Typ, Protected_Mode));
Insert_After (Current_Node, Sub);
Analyze (Sub);
Current_Node := Sub;
-- Generate an overriding primitive operation specification for
-- this subprogram if the protected type implements an interface
-- and Build_Wrapper_Spec did not generate its wrapper.
if Ada_Version >= Ada_2005
and then
Present (Interfaces (Corresponding_Record_Type (Prot_Typ)))
then
declare
Found : Boolean := False;
Prim_Elmt : Elmt_Id;
Prim_Op : Node_Id;
begin
Prim_Elmt :=
First_Elmt
(Primitive_Operations
(Corresponding_Record_Type (Prot_Typ)));
while Present (Prim_Elmt) loop
Prim_Op := Node (Prim_Elmt);
if Is_Primitive_Wrapper (Prim_Op)
and then Wrapped_Entity (Prim_Op) =
Defining_Entity (Specification (Comp))
then
Found := True;
exit;
end if;
Next_Elmt (Prim_Elmt);
end loop;
if not Found then
Sub :=
Make_Subprogram_Declaration (Loc,
Specification =>
Build_Protected_Sub_Specification
(Comp, Prot_Typ, Dispatching_Mode));
Insert_After (Current_Node, Sub);
Analyze (Sub);
Current_Node := Sub;
end if;
end;
end if;
-- If a pragma Interrupt_Handler applies, build and add a call to
-- Register_Interrupt_Handler to the freezing actions of the
-- protected version (Current_Node) of the subprogram:
-- system.interrupts.register_interrupt_handler
-- (prot_procP'address);
if not Restricted_Profile
and then Is_Interrupt_Handler
(Defining_Unit_Name (Specification (Comp)))
then
Register_Handler;
end if;
elsif Nkind (Comp) = N_Entry_Declaration then
Expand_Entry_Declaration (Comp);
end if;
Next (Comp);
end loop;
-- If there are some private entry declarations, expand it as if they
-- were visible entries.
if Present (Private_Declarations (Pdef)) then
Comp := First (Private_Declarations (Pdef));
while Present (Comp) loop
if Nkind (Comp) = N_Entry_Declaration then
Expand_Entry_Declaration (Comp);
end if;
Next (Comp);
end loop;
end if;
-- Create the declaration of an array object which contains the values
-- of aspect/pragma Max_Queue_Length for all entries of the protected
-- type. This object is later passed to the appropriate protected object
-- initialization routine.
if Has_Entries (Prot_Typ)
and then Corresponding_Runtime_Package (Prot_Typ) =
System_Tasking_Protected_Objects_Entries
then
declare
Count : Int;
Item : Entity_Id;
Max_Vals : Node_Id;
Maxes : List_Id;
Maxes_Id : Entity_Id;
Need_Array : Boolean := False;
begin
-- First check if there is any Max_Queue_Length pragma
Item := First_Entity (Prot_Typ);
while Present (Item) loop
if Is_Entry (Item) and then Has_Max_Queue_Length (Item) then
Need_Array := True;
exit;
end if;
Next_Entity (Item);
end loop;
-- Gather the Max_Queue_Length values of all entries in a list. A
-- value of zero indicates that the entry has no limitation on its
-- queue length.
if Need_Array then
Count := 0;
Item := First_Entity (Prot_Typ);
Maxes := New_List;
while Present (Item) loop
if Is_Entry (Item) then
Count := Count + 1;
Append_To (Maxes,
Make_Integer_Literal
(Loc, Get_Max_Queue_Length (Item)));
end if;
Next_Entity (Item);
end loop;
-- Create the declaration of the array object. Generate:
-- Maxes_Id : aliased constant
-- Protected_Entry_Queue_Max_Array
-- (1 .. Count) := (..., ...);
Maxes_Id :=
Make_Defining_Identifier (Loc,
Chars => New_External_Name (Chars (Prot_Typ), 'B'));
Max_Vals :=
Make_Object_Declaration (Loc,
Defining_Identifier => Maxes_Id,
Aliased_Present => True,
Constant_Present => True,
Object_Definition =>
Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of
(RTE (RE_Protected_Entry_Queue_Max_Array), Loc),
Constraint =>
Make_Index_Or_Discriminant_Constraint (Loc,
Constraints => New_List (
Make_Range (Loc,
Make_Integer_Literal (Loc, 1),
Make_Integer_Literal (Loc, Count))))),
Expression => Make_Aggregate (Loc, Maxes));
-- A pointer to this array will be placed in the corresponding
-- record by its initialization procedure so this needs to be
-- analyzed here.
Insert_After (Current_Node, Max_Vals);
Current_Node := Max_Vals;
Analyze (Max_Vals);
Set_Entry_Max_Queue_Lengths_Array (Prot_Typ, Maxes_Id);
end if;
end;
end if;
-- Emit declaration for Entry_Bodies_Array, now that the addresses of
-- all protected subprograms have been collected.
if Has_Entries (Prot_Typ) then
Body_Id :=
Make_Defining_Identifier (Sloc (Prot_Typ),
Chars => New_External_Name (Chars (Prot_Typ), 'A'));
case Corresponding_Runtime_Package (Prot_Typ) is
when System_Tasking_Protected_Objects_Entries =>
Expr := Entries_Aggr;
Obj_Def :=
Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of
(RTE (RE_Protected_Entry_Body_Array), Loc),
Constraint =>
Make_Index_Or_Discriminant_Constraint (Loc,
Constraints => New_List (
Make_Range (Loc,
Make_Integer_Literal (Loc, 1),
Make_Integer_Literal (Loc, E_Count)))));
when System_Tasking_Protected_Objects_Single_Entry =>
Expr := Remove_Head (Expressions (Entries_Aggr));
Obj_Def := New_Occurrence_Of (RTE (RE_Entry_Body), Loc);
when others =>
raise Program_Error;
end case;
Body_Arr :=
Make_Object_Declaration (Loc,
Defining_Identifier => Body_Id,
Aliased_Present => True,
Constant_Present => True,
Object_Definition => Obj_Def,
Expression => Expr);
-- A pointer to this array will be placed in the corresponding record
-- by its initialization procedure so this needs to be analyzed here.
Insert_After (Current_Node, Body_Arr);
Current_Node := Body_Arr;
Analyze (Body_Arr);
Set_Entry_Bodies_Array (Prot_Typ, Body_Id);
-- Finally, build the function that maps an entry index into the
-- corresponding body. A pointer to this function is placed in each
-- object of the type. Except for a ravenscar-like profile (no abort,
-- no entry queue, 1 entry)
if Corresponding_Runtime_Package (Prot_Typ) =
System_Tasking_Protected_Objects_Entries
then
Sub :=
Make_Subprogram_Declaration (Loc,
Specification => Build_Find_Body_Index_Spec (Prot_Typ));
Insert_After (Current_Node, Sub);
Analyze (Sub);
end if;
end if;
end Expand_N_Protected_Type_Declaration;
--------------------------------
-- Expand_N_Requeue_Statement --
--------------------------------
-- A nondispatching requeue statement is expanded into one of four GNARLI
-- operations, depending on the source and destination (task or protected
-- object). A dispatching requeue statement is expanded into a call to the
-- predefined primitive _Disp_Requeue. In addition, code is generated to
-- jump around the remainder of processing for the original entry and, if
-- the destination is (different) protected object, to attempt to service
-- it. The following illustrates the various cases:
-- procedure entE
-- (O : System.Address;
-- P : System.Address;
-- E : Protected_Entry_Index)
-- is
-- <discriminant renamings>
-- <private object renamings>
-- type poVP is access poV;
-- _object : ptVP := ptVP!(O);
-- begin
-- begin
-- <start of statement sequence for entry>
-- -- Requeue from one protected entry body to another protected
-- -- entry.
-- Requeue_Protected_Entry (
-- _object._object'Access,
-- new._object'Access,
-- E,
-- Abort_Present);
-- return;
-- <some more of the statement sequence for entry>
-- -- Requeue from an entry body to a task entry
-- Requeue_Protected_To_Task_Entry (
-- New._task_id,
-- E,
-- Abort_Present);
-- return;
-- <rest of statement sequence for entry>
-- Complete_Entry_Body (_object._object);
-- exception
-- when all others =>
-- Exceptional_Complete_Entry_Body (
-- _object._object, Get_GNAT_Exception);
-- end;
-- end entE;
-- Requeue of a task entry call to a task entry
-- Accept_Call (E, Ann);
-- <start of statement sequence for accept statement>
-- Requeue_Task_Entry (New._task_id, E, Abort_Present);
-- goto Lnn;
-- <rest of statement sequence for accept statement>
-- <<Lnn>>
-- Complete_Rendezvous;
-- exception
-- when all others =>
-- Exceptional_Complete_Rendezvous (Get_GNAT_Exception);
-- Requeue of a task entry call to a protected entry
-- Accept_Call (E, Ann);
-- <start of statement sequence for accept statement>
-- Requeue_Task_To_Protected_Entry (
-- new._object'Access,
-- E,
-- Abort_Present);
-- newS (new, Pnn);
-- goto Lnn;
-- <rest of statement sequence for accept statement>
-- <<Lnn>>
-- Complete_Rendezvous;
-- exception
-- when all others =>
-- Exceptional_Complete_Rendezvous (Get_GNAT_Exception);
-- Ada 2012 (AI05-0030): Dispatching requeue to an interface primitive
-- marked by pragma Implemented (XXX, By_Entry).
-- The requeue is inside a protected entry:
-- procedure entE
-- (O : System.Address;
-- P : System.Address;
-- E : Protected_Entry_Index)
-- is
-- <discriminant renamings>
-- <private object renamings>
-- type poVP is access poV;
-- _object : ptVP := ptVP!(O);
-- begin
-- begin
-- <start of statement sequence for entry>
-- _Disp_Requeue
-- (<interface class-wide object>,
-- True,
-- _object'Address,
-- Ada.Tags.Get_Offset_Index
-- (Tag (_object),
-- <interface dispatch table index of target entry>),
-- Abort_Present);
-- return;
-- <rest of statement sequence for entry>
-- Complete_Entry_Body (_object._object);
-- exception
-- when all others =>
-- Exceptional_Complete_Entry_Body (
-- _object._object, Get_GNAT_Exception);
-- end;
-- end entE;
-- The requeue is inside a task entry:
-- Accept_Call (E, Ann);
-- <start of statement sequence for accept statement>
-- _Disp_Requeue
-- (<interface class-wide object>,
-- False,
-- null,
-- Ada.Tags.Get_Offset_Index
-- (Tag (_object),
-- <interface dispatch table index of target entrt>),
-- Abort_Present);
-- newS (new, Pnn);
-- goto Lnn;
-- <rest of statement sequence for accept statement>
-- <<Lnn>>
-- Complete_Rendezvous;
-- exception
-- when all others =>
-- Exceptional_Complete_Rendezvous (Get_GNAT_Exception);
-- Ada 2012 (AI05-0030): Dispatching requeue to an interface primitive
-- marked by pragma Implemented (XXX, By_Protected_Procedure). The requeue
-- statement is replaced by a dispatching call with actual parameters taken
-- from the inner-most accept statement or entry body.
-- Target.Primitive (Param1, ..., ParamN);
-- Ada 2012 (AI05-0030): Dispatching requeue to an interface primitive
-- marked by pragma Implemented (XXX, By_Any | Optional) or not marked
-- at all.
-- declare
-- S : constant Offset_Index :=
-- Get_Offset_Index (Tag (Concval), DT_Position (Ename));
-- C : constant Prim_Op_Kind := Get_Prim_Op_Kind (Tag (Concval), S);
-- begin
-- if C = POK_Protected_Entry
-- or else C = POK_Task_Entry
-- then
-- <statements for dispatching requeue>
-- elsif C = POK_Protected_Procedure then
-- <dispatching call equivalent>
-- else
-- raise Program_Error;
-- end if;
-- end;
procedure Expand_N_Requeue_Statement (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Conc_Typ : Entity_Id;
Concval : Node_Id;
Ename : Node_Id;
Enc_Subp : Entity_Id;
Index : Node_Id;
Old_Typ : Entity_Id;
function Build_Dispatching_Call_Equivalent return Node_Id;
-- Ada 2012 (AI05-0030): N denotes a dispatching requeue statement of
-- the form Concval.Ename. It is statically known that Ename is allowed
-- to be implemented by a protected procedure. Create a dispatching call
-- equivalent of Concval.Ename taking the actual parameters from the
-- inner-most accept statement or entry body.
function Build_Dispatching_Requeue return Node_Id;
-- Ada 2012 (AI05-0030): N denotes a dispatching requeue statement of
-- the form Concval.Ename. It is statically known that Ename is allowed
-- to be implemented by a protected or a task entry. Create a call to
-- primitive _Disp_Requeue which handles the low-level actions.
function Build_Dispatching_Requeue_To_Any return Node_Id;
-- Ada 2012 (AI05-0030): N denotes a dispatching requeue statement of
-- the form Concval.Ename. Ename is either marked by pragma Implemented
-- (XXX, By_Any | Optional) or not marked at all. Create a block which
-- determines at runtime whether Ename denotes an entry or a procedure
-- and perform the appropriate kind of dispatching select.
function Build_Normal_Requeue return Node_Id;
-- N denotes a nondispatching requeue statement to either a task or a
-- protected entry. Build the appropriate runtime call to perform the
-- action.
function Build_Skip_Statement (Search : Node_Id) return Node_Id;
-- For a protected entry, create a return statement to skip the rest of
-- the entry body. Otherwise, create a goto statement to skip the rest
-- of a task accept statement. The lookup for the enclosing entry body
-- or accept statement starts from Search.
---------------------------------------
-- Build_Dispatching_Call_Equivalent --
---------------------------------------
function Build_Dispatching_Call_Equivalent return Node_Id is
Call_Ent : constant Entity_Id := Entity (Ename);
Obj : constant Node_Id := Original_Node (Concval);
Acc_Ent : Node_Id;
Actuals : List_Id;
Formal : Node_Id;
Formals : List_Id;
begin
-- Climb the parent chain looking for the inner-most entry body or
-- accept statement.
Acc_Ent := N;
while Present (Acc_Ent)
and then Nkind (Acc_Ent) not in N_Accept_Statement | N_Entry_Body
loop
Acc_Ent := Parent (Acc_Ent);
end loop;
-- A requeue statement should be housed inside an entry body or an
-- accept statement at some level. If this is not the case, then the
-- tree is malformed.
pragma Assert (Present (Acc_Ent));
-- Recover the list of formal parameters
if Nkind (Acc_Ent) = N_Entry_Body then
Acc_Ent := Entry_Body_Formal_Part (Acc_Ent);
end if;
Formals := Parameter_Specifications (Acc_Ent);
-- Create the actual parameters for the dispatching call. These are
-- simply copies of the entry body or accept statement formals in the
-- same order as they appear.
Actuals := No_List;
if Present (Formals) then
Actuals := New_List;
Formal := First (Formals);
while Present (Formal) loop
Append_To (Actuals,
Make_Identifier (Loc, Chars (Defining_Identifier (Formal))));
Next (Formal);
end loop;
end if;
-- Generate:
-- Obj.Call_Ent (Actuals);
return
Make_Procedure_Call_Statement (Loc,
Name =>
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Chars (Obj)),
Selector_Name => Make_Identifier (Loc, Chars (Call_Ent))),
Parameter_Associations => Actuals);
end Build_Dispatching_Call_Equivalent;
-------------------------------
-- Build_Dispatching_Requeue --
-------------------------------
function Build_Dispatching_Requeue return Node_Id is
Params : constant List_Id := New_List;
begin
-- Process the "with abort" parameter
Prepend_To (Params,
New_Occurrence_Of (Boolean_Literals (Abort_Present (N)), Loc));
-- Process the entry wrapper's position in the primary dispatch
-- table parameter. Generate:
-- Ada.Tags.Get_Entry_Index
-- (T => To_Tag_Ptr (Obj'Address).all,
-- Position =>
-- Ada.Tags.Get_Offset_Index
-- (Ada.Tags.Tag (Concval),
-- <interface dispatch table position of Ename>));
-- Note that Obj'Address is recursively expanded into a call to
-- Base_Address (Obj).
if Tagged_Type_Expansion then
Prepend_To (Params,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Get_Entry_Index), Loc),
Parameter_Associations => New_List (
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Tag_Ptr),
Make_Attribute_Reference (Loc,
Prefix => New_Copy_Tree (Concval),
Attribute_Name => Name_Address))),
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Get_Offset_Index), Loc),
Parameter_Associations => New_List (
Unchecked_Convert_To (RTE (RE_Tag), Concval),
Make_Integer_Literal (Loc,
DT_Position (Entity (Ename))))))));
-- VM targets
else
Prepend_To (Params,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Get_Entry_Index), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => Concval,
Attribute_Name => Name_Tag),
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Get_Offset_Index), Loc),
Parameter_Associations => New_List (
-- Obj_Tag
Make_Attribute_Reference (Loc,
Prefix => Concval,
Attribute_Name => Name_Tag),
-- Tag_Typ
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Etype (Concval), Loc),
Attribute_Name => Name_Tag),
-- Position
Make_Integer_Literal (Loc,
DT_Position (Entity (Ename))))))));
end if;
-- Specific actuals for protected to XXX requeue
if Is_Protected_Type (Old_Typ) then
Prepend_To (Params,
Make_Attribute_Reference (Loc, -- _object'Address
Prefix =>
Concurrent_Ref (New_Occurrence_Of (Old_Typ, Loc)),
Attribute_Name => Name_Address));
Prepend_To (Params, -- True
New_Occurrence_Of (Standard_True, Loc));
-- Specific actuals for task to XXX requeue
else
pragma Assert (Is_Task_Type (Old_Typ));
Prepend_To (Params, -- null
New_Occurrence_Of (RTE (RE_Null_Address), Loc));
Prepend_To (Params, -- False
New_Occurrence_Of (Standard_False, Loc));
end if;
-- Add the object parameter
Prepend_To (Params, New_Copy_Tree (Concval));
-- Generate:
-- _Disp_Requeue (<Params>);
-- Find entity for Disp_Requeue operation, which belongs to
-- the type and may not be directly visible.
declare
Elmt : Elmt_Id;
Op : Entity_Id := Empty;
begin
Elmt := First_Elmt (Primitive_Operations (Etype (Conc_Typ)));
while Present (Elmt) loop
Op := Node (Elmt);
exit when Chars (Op) = Name_uDisp_Requeue;
Next_Elmt (Elmt);
end loop;
pragma Assert (Present (Op));
return
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (Op, Loc),
Parameter_Associations => Params);
end;
end Build_Dispatching_Requeue;
--------------------------------------
-- Build_Dispatching_Requeue_To_Any --
--------------------------------------
function Build_Dispatching_Requeue_To_Any return Node_Id is
Call_Ent : constant Entity_Id := Entity (Ename);
Obj : constant Node_Id := Original_Node (Concval);
Skip : constant Node_Id := Build_Skip_Statement (N);
C : Entity_Id;
Decls : List_Id;
S : Entity_Id;
Stmts : List_Id;
begin
Decls := New_List;
Stmts := New_List;
-- Dispatch table slot processing, generate:
-- S : Integer;
S := Build_S (Loc, Decls);
-- Call kind processing, generate:
-- C : Ada.Tags.Prim_Op_Kind;
C := Build_C (Loc, Decls);
-- Generate:
-- S := Ada.Tags.Get_Offset_Index
-- (Ada.Tags.Tag (Obj), DT_Position (Call_Ent));
Append_To (Stmts, Build_S_Assignment (Loc, S, Obj, Call_Ent));
-- Generate:
-- _Disp_Get_Prim_Op_Kind (Obj, S, C);
Append_To (Stmts,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of (
Find_Prim_Op (Etype (Etype (Obj)),
Name_uDisp_Get_Prim_Op_Kind),
Loc),
Parameter_Associations => New_List (
New_Copy_Tree (Obj),
New_Occurrence_Of (S, Loc),
New_Occurrence_Of (C, Loc))));
Append_To (Stmts,
-- if C = POK_Protected_Entry
-- or else C = POK_Task_Entry
-- then
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Or (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_POK_Protected_Entry), Loc)),
Right_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_POK_Task_Entry), Loc))),
-- Dispatching requeue equivalent
Then_Statements => New_List (
Build_Dispatching_Requeue,
Skip),
-- elsif C = POK_Protected_Procedure then
Elsif_Parts => New_List (
Make_Elsif_Part (Loc,
Condition =>
Make_Op_Eq (Loc,
Left_Opnd =>
New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (
RTE (RE_POK_Protected_Procedure), Loc)),
-- Dispatching call equivalent
Then_Statements => New_List (
Build_Dispatching_Call_Equivalent))),
-- else
-- raise Program_Error;
-- end if;
Else_Statements => New_List (
Make_Raise_Program_Error (Loc,
Reason => PE_Explicit_Raise))));
-- Wrap everything into a block
return
Make_Block_Statement (Loc,
Declarations => Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Stmts));
end Build_Dispatching_Requeue_To_Any;
--------------------------
-- Build_Normal_Requeue --
--------------------------
function Build_Normal_Requeue return Node_Id is
Params : constant List_Id := New_List;
Param : Node_Id;
RT_Call : Node_Id;
begin
-- Process the "with abort" parameter
Prepend_To (Params,
New_Occurrence_Of (Boolean_Literals (Abort_Present (N)), Loc));
-- Add the index expression to the parameters. It is common among all
-- four cases.
Prepend_To (Params,
Entry_Index_Expression (Loc, Entity (Ename), Index, Conc_Typ));
if Is_Protected_Type (Old_Typ) then
declare
Self_Param : Node_Id;
begin
Self_Param :=
Make_Attribute_Reference (Loc,
Prefix =>
Concurrent_Ref (New_Occurrence_Of (Old_Typ, Loc)),
Attribute_Name =>
Name_Unchecked_Access);
-- Protected to protected requeue
if Is_Protected_Type (Conc_Typ) then
RT_Call :=
New_Occurrence_Of (
RTE (RE_Requeue_Protected_Entry), Loc);
Param :=
Make_Attribute_Reference (Loc,
Prefix =>
Concurrent_Ref (Concval),
Attribute_Name =>
Name_Unchecked_Access);
-- Protected to task requeue
else pragma Assert (Is_Task_Type (Conc_Typ));
RT_Call :=
New_Occurrence_Of (
RTE (RE_Requeue_Protected_To_Task_Entry), Loc);
Param := Concurrent_Ref (Concval);
end if;
Prepend_To (Params, Param);
Prepend_To (Params, Self_Param);
end;
else pragma Assert (Is_Task_Type (Old_Typ));
-- Task to protected requeue
if Is_Protected_Type (Conc_Typ) then
RT_Call :=
New_Occurrence_Of (
RTE (RE_Requeue_Task_To_Protected_Entry), Loc);
Param :=
Make_Attribute_Reference (Loc,
Prefix =>
Concurrent_Ref (Concval),
Attribute_Name =>
Name_Unchecked_Access);
-- Task to task requeue
else pragma Assert (Is_Task_Type (Conc_Typ));
RT_Call :=
New_Occurrence_Of (RTE (RE_Requeue_Task_Entry), Loc);
Param := Concurrent_Ref (Concval);
end if;
Prepend_To (Params, Param);
end if;
return
Make_Procedure_Call_Statement (Loc,
Name => RT_Call,
Parameter_Associations => Params);
end Build_Normal_Requeue;
--------------------------
-- Build_Skip_Statement --
--------------------------
function Build_Skip_Statement (Search : Node_Id) return Node_Id is
Skip_Stmt : Node_Id;
begin
-- Build a return statement to skip the rest of the entire body
if Is_Protected_Type (Old_Typ) then
Skip_Stmt := Make_Simple_Return_Statement (Loc);
-- If the requeue is within a task, find the end label of the
-- enclosing accept statement and create a goto statement to it.
else
declare
Acc : Node_Id;
Label : Node_Id;
begin
-- Climb the parent chain looking for the enclosing accept
-- statement.
Acc := Parent (Search);
while Present (Acc)
and then Nkind (Acc) /= N_Accept_Statement
loop
Acc := Parent (Acc);
end loop;
-- The last statement is the second label used for completing
-- the rendezvous the usual way. The label we are looking for
-- is right before it.
Label :=
Prev (Last (Statements (Handled_Statement_Sequence (Acc))));
pragma Assert (Nkind (Label) = N_Label);
-- Generate a goto statement to skip the rest of the accept
Skip_Stmt :=
Make_Goto_Statement (Loc,
Name =>
New_Occurrence_Of (Entity (Identifier (Label)), Loc));
end;
end if;
Set_Analyzed (Skip_Stmt);
return Skip_Stmt;
end Build_Skip_Statement;
-- Start of processing for Expand_N_Requeue_Statement
begin
-- Extract the components of the entry call
Extract_Entry (N, Concval, Ename, Index);
Conc_Typ := Etype (Concval);
-- Examine the scope stack in order to find nearest enclosing concurrent
-- type. This will constitute our invocation source.
Old_Typ := Current_Scope;
while Present (Old_Typ)
and then not Is_Concurrent_Type (Old_Typ)
loop
Old_Typ := Scope (Old_Typ);
end loop;
-- Obtain the innermost enclosing callable construct for use in
-- generating a dynamic accessibility check.
Enc_Subp := Current_Scope;
if Ekind (Enc_Subp) not in Entry_Kind | Subprogram_Kind then
Enc_Subp := Enclosing_Subprogram (Enc_Subp);
end if;
-- Generate a dynamic accessibility check on the target object
Insert_Before_And_Analyze (N,
Make_Raise_Program_Error (Loc,
Condition =>
Make_Op_Gt (Loc,
Left_Opnd => Accessibility_Level (Name (N), Dynamic_Level),
Right_Opnd => Make_Integer_Literal (Loc,
Scope_Depth (Enc_Subp))),
Reason => PE_Accessibility_Check_Failed));
-- Ada 2012 (AI05-0030): We have a dispatching requeue of the form
-- Concval.Ename where the type of Concval is class-wide concurrent
-- interface.
if Ada_Version >= Ada_2012
and then Present (Concval)
and then Is_Class_Wide_Type (Conc_Typ)
and then Is_Concurrent_Interface (Conc_Typ)
then
declare
Has_Impl : Boolean := False;
Impl_Kind : Name_Id := No_Name;
begin
-- Check whether the Ename is flagged by pragma Implemented
if Has_Rep_Pragma (Entity (Ename), Name_Implemented) then
Has_Impl := True;
Impl_Kind := Implementation_Kind (Entity (Ename));
end if;
-- The procedure_or_entry_NAME is guaranteed to be overridden by
-- an entry. Create a call to predefined primitive _Disp_Requeue.
if Has_Impl and then Impl_Kind = Name_By_Entry then
Rewrite (N, Build_Dispatching_Requeue);
Analyze (N);
Insert_After (N, Build_Skip_Statement (N));
-- The procedure_or_entry_NAME is guaranteed to be overridden by
-- a protected procedure. In this case the requeue is transformed
-- into a dispatching call.
elsif Has_Impl
and then Impl_Kind = Name_By_Protected_Procedure
then
Rewrite (N, Build_Dispatching_Call_Equivalent);
Analyze (N);
-- The procedure_or_entry_NAME's implementation kind is either
-- By_Any, Optional, or pragma Implemented was not applied at all.
-- In this case a runtime test determines whether Ename denotes an
-- entry or a protected procedure and performs the appropriate
-- call.
else
Rewrite (N, Build_Dispatching_Requeue_To_Any);
Analyze (N);
end if;
end;
-- Processing for regular (nondispatching) requeues
else
Rewrite (N, Build_Normal_Requeue);
Analyze (N);
Insert_After (N, Build_Skip_Statement (N));
end if;
end Expand_N_Requeue_Statement;
-------------------------------
-- Expand_N_Selective_Accept --
-------------------------------
procedure Expand_N_Selective_Accept (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Alts : constant List_Id := Select_Alternatives (N);
-- Note: in the below declarations a lot of new lists are allocated
-- unconditionally which may well not end up being used. That's not
-- a good idea since it wastes space gratuitously ???
Accept_Case : List_Id;
Accept_List : constant List_Id := New_List;
Alt : Node_Id;
Alt_List : constant List_Id := New_List;
Alt_Stats : List_Id;
Ann : Entity_Id := Empty;
Check_Guard : Boolean := True;
Decls : constant List_Id := New_List;
Stats : constant List_Id := New_List;
Body_List : constant List_Id := New_List;
Trailing_List : constant List_Id := New_List;
Choices : List_Id;
Else_Present : Boolean := False;
Terminate_Alt : Node_Id := Empty;
Select_Mode : Node_Id;
Delay_Case : List_Id;
Delay_Count : Integer := 0;
Delay_Val : Entity_Id;
Delay_Index : Entity_Id;
Delay_Min : Entity_Id;
Delay_Num : Pos := 1;
Delay_Alt_List : List_Id := New_List;
Delay_List : constant List_Id := New_List;
D : Entity_Id;
M : Entity_Id;
First_Delay : Boolean := True;
Guard_Open : Entity_Id;
End_Lab : Node_Id;
Index : Pos := 1;
Lab : Node_Id;
Num_Alts : Nat;
Num_Accept : Nat := 0;
Proc : Node_Id;
Time_Type : Entity_Id := Empty;
Select_Call : Node_Id;
Qnam : constant Entity_Id :=
Make_Defining_Identifier (Loc, New_External_Name ('S', 0));
Xnam : constant Entity_Id :=
Make_Defining_Identifier (Loc, New_External_Name ('J', 1));
-----------------------
-- Local subprograms --
-----------------------
function Accept_Or_Raise return List_Id;
-- For the rare case where delay alternatives all have guards, and
-- all of them are closed, it is still possible that there were open
-- accept alternatives with no callers. We must reexamine the
-- Accept_List, and execute a selective wait with no else if some
-- accept is open. If none, we raise program_error.
procedure Add_Accept (Alt : Node_Id);
-- Process a single accept statement in a select alternative. Build
-- procedure for body of accept, and add entry to dispatch table with
-- expression for guard, in preparation for call to run time select.
function Make_And_Declare_Label (Num : Int) return Node_Id;
-- Manufacture a label using Num as a serial number and declare it.
-- The declaration is appended to Decls. The label marks the trailing
-- statements of an accept or delay alternative.
function Make_Select_Call (Select_Mode : Entity_Id) return Node_Id;
-- Build call to Selective_Wait runtime routine
procedure Process_Delay_Alternative (Alt : Node_Id; Index : Int);
-- Add code to compare value of delay with previous values, and
-- generate case entry for trailing statements.
procedure Process_Accept_Alternative
(Alt : Node_Id;
Index : Int;
Proc : Node_Id);
-- Add code to call corresponding procedure, and branch to
-- trailing statements, if any.
---------------------
-- Accept_Or_Raise --
---------------------
function Accept_Or_Raise return List_Id is
Cond : Node_Id;
Stats : List_Id;
J : constant Entity_Id := Make_Temporary (Loc, 'J');
begin
-- We generate the following:
-- for J in q'range loop
-- if q(J).S /=null_task_entry then
-- selective_wait (simple_mode,...);
-- done := True;
-- exit;
-- end if;
-- end loop;
--
-- if no rendez_vous then
-- raise program_error;
-- end if;
-- Note that the code needs to know that the selector name
-- in an Accept_Alternative is named S.
Cond := Make_Op_Ne (Loc,
Left_Opnd =>
Make_Selected_Component (Loc,
Prefix =>
Make_Indexed_Component (Loc,
Prefix => New_Occurrence_Of (Qnam, Loc),
Expressions => New_List (New_Occurrence_Of (J, Loc))),
Selector_Name => Make_Identifier (Loc, Name_S)),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_Null_Task_Entry), Loc));
Stats := New_List (
Make_Implicit_Loop_Statement (N,
Iteration_Scheme =>
Make_Iteration_Scheme (Loc,
Loop_Parameter_Specification =>
Make_Loop_Parameter_Specification (Loc,
Defining_Identifier => J,
Discrete_Subtype_Definition =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Qnam, Loc),
Attribute_Name => Name_Range,
Expressions => New_List (
Make_Integer_Literal (Loc, 1))))),
Statements => New_List (
Make_Implicit_If_Statement (N,
Condition => Cond,
Then_Statements => New_List (
Make_Select_Call (
New_Occurrence_Of (RTE (RE_Simple_Mode), Loc)),
Make_Exit_Statement (Loc))))));
Append_To (Stats,
Make_Raise_Program_Error (Loc,
Condition => Make_Op_Eq (Loc,
Left_Opnd => New_Occurrence_Of (Xnam, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_No_Rendezvous), Loc)),
Reason => PE_All_Guards_Closed));
return Stats;
end Accept_Or_Raise;
----------------
-- Add_Accept --
----------------
procedure Add_Accept (Alt : Node_Id) is
Acc_Stm : constant Node_Id := Accept_Statement (Alt);
Ename : constant Node_Id := Entry_Direct_Name (Acc_Stm);
Eloc : constant Source_Ptr := Sloc (Ename);
Eent : constant Entity_Id := Entity (Ename);
Index : constant Node_Id := Entry_Index (Acc_Stm);
Call : Node_Id;
Expr : Node_Id;
Null_Body : Node_Id;
PB_Ent : Entity_Id;
Proc_Body : Node_Id;
-- Start of processing for Add_Accept
begin
if No (Ann) then
Ann := Node (Last_Elmt (Accept_Address (Eent)));
end if;
if Present (Condition (Alt)) then
Expr :=
Make_If_Expression (Eloc, New_List (
Condition (Alt),
Entry_Index_Expression (Eloc, Eent, Index, Scope (Eent)),
New_Occurrence_Of (RTE (RE_Null_Task_Entry), Eloc)));
else
Expr := Entry_Index_Expression (Eloc, Eent, Index, Scope (Eent));
end if;
if Present (Handled_Statement_Sequence (Accept_Statement (Alt))) then
Null_Body := New_Occurrence_Of (Standard_False, Eloc);
-- Always add call to Abort_Undefer when generating code, since
-- this is what the runtime expects (abort deferred in
-- Selective_Wait). In CodePeer mode this only confuses the
-- analysis with unknown calls, so don't do it.
if not CodePeer_Mode then
Call := Build_Runtime_Call (Loc, RE_Abort_Undefer);
Insert_Before
(First (Statements (Handled_Statement_Sequence
(Accept_Statement (Alt)))),
Call);
Analyze (Call);
end if;
PB_Ent :=
Make_Defining_Identifier (Eloc,
New_External_Name (Chars (Ename), 'A', Num_Accept));
-- Link the acceptor to the original receiving entry
Mutate_Ekind (PB_Ent, E_Procedure);
Set_Receiving_Entry (PB_Ent, Eent);
if Comes_From_Source (Alt) then
Set_Debug_Info_Needed (PB_Ent);
end if;
Proc_Body :=
Make_Subprogram_Body (Eloc,
Specification =>
Make_Procedure_Specification (Eloc,
Defining_Unit_Name => PB_Ent),
Declarations => Declarations (Acc_Stm),
Handled_Statement_Sequence =>
Build_Accept_Body (Accept_Statement (Alt)));
Reset_Scopes_To (Proc_Body, PB_Ent);
-- During the analysis of the body of the accept statement, any
-- zero cost exception handler records were collected in the
-- Accept_Handler_Records field of the N_Accept_Alternative node.
-- This is where we move them to where they belong, namely the
-- newly created procedure.
Set_Handler_Records (PB_Ent, Accept_Handler_Records (Alt));
Append (Proc_Body, Body_List);
else
Null_Body := New_Occurrence_Of (Standard_True, Eloc);
-- if accept statement has declarations, insert above, given that
-- we are not creating a body for the accept.
if Present (Declarations (Acc_Stm)) then
Insert_Actions (N, Declarations (Acc_Stm));
end if;
end if;
Append_To (Accept_List,
Make_Aggregate (Eloc, Expressions => New_List (Null_Body, Expr)));
Num_Accept := Num_Accept + 1;
end Add_Accept;
----------------------------
-- Make_And_Declare_Label --
----------------------------
function Make_And_Declare_Label (Num : Int) return Node_Id is
Lab_Id : Node_Id;
begin
Lab_Id := Make_Identifier (Loc, New_External_Name ('L', Num));
Lab :=
Make_Label (Loc, Lab_Id);
Append_To (Decls,
Make_Implicit_Label_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Chars (Lab_Id)),
Label_Construct => Lab));
return Lab;
end Make_And_Declare_Label;
----------------------
-- Make_Select_Call --
----------------------
function Make_Select_Call (Select_Mode : Entity_Id) return Node_Id is
Params : constant List_Id := New_List;
begin
Append_To (Params,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Qnam, Loc),
Attribute_Name => Name_Unchecked_Access));
Append_To (Params, Select_Mode);
Append_To (Params, New_Occurrence_Of (Ann, Loc));
Append_To (Params, New_Occurrence_Of (Xnam, Loc));
return
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Selective_Wait), Loc),
Parameter_Associations => Params);
end Make_Select_Call;
--------------------------------
-- Process_Accept_Alternative --
--------------------------------
procedure Process_Accept_Alternative
(Alt : Node_Id;
Index : Int;
Proc : Node_Id)
is
Astmt : constant Node_Id := Accept_Statement (Alt);
Alt_Stats : List_Id;
begin
Adjust_Condition (Condition (Alt));
-- Accept with body
if Present (Handled_Statement_Sequence (Astmt)) then
Alt_Stats :=
New_List (
Make_Procedure_Call_Statement (Sloc (Proc),
Name =>
New_Occurrence_Of
(Defining_Unit_Name (Specification (Proc)),
Sloc (Proc))));
-- Accept with no body (followed by trailing statements)
else
declare
Entry_Id : constant Entity_Id :=
Entity (Entry_Direct_Name (Accept_Statement (Alt)));
begin
-- Ada 2022 (AI12-0279)
if Has_Yield_Aspect (Entry_Id)
and then RTE_Available (RE_Yield)
then
Alt_Stats :=
New_List (
Make_Procedure_Call_Statement (Sloc (Proc),
New_Occurrence_Of (RTE (RE_Yield), Sloc (Proc))));
else
Alt_Stats := Empty_List;
end if;
end;
end if;
Ensure_Statement_Present (Sloc (Astmt), Alt);
-- After the call, if any, branch to trailing statements, if any.
-- We create a label for each, as well as the corresponding label
-- declaration.
if not Is_Empty_List (Statements (Alt)) then
Lab := Make_And_Declare_Label (Index);
Append (Lab, Trailing_List);
Append_List (Statements (Alt), Trailing_List);
Append_To (Trailing_List,
Make_Goto_Statement (Loc,
Name => New_Copy (Identifier (End_Lab))));
else
Lab := End_Lab;
end if;
Append_To (Alt_Stats,
Make_Goto_Statement (Loc, Name => New_Copy (Identifier (Lab))));
Append_To (Alt_List,
Make_Case_Statement_Alternative (Loc,
Discrete_Choices => New_List (Make_Integer_Literal (Loc, Index)),
Statements => Alt_Stats));
end Process_Accept_Alternative;
-------------------------------
-- Process_Delay_Alternative --
-------------------------------
procedure Process_Delay_Alternative (Alt : Node_Id; Index : Int) is
Dloc : constant Source_Ptr := Sloc (Delay_Statement (Alt));
Cond : Node_Id;
Delay_Alt : List_Id;
begin
-- Deal with C/Fortran boolean as delay condition
Adjust_Condition (Condition (Alt));
-- Determine the smallest specified delay
-- for each delay alternative generate:
-- if guard-expression then
-- Delay_Val := delay-expression;
-- Guard_Open := True;
-- if Delay_Val < Delay_Min then
-- Delay_Min := Delay_Val;
-- Delay_Index := Index;
-- end if;
-- end if;
-- The enclosing if-statement is omitted if there is no guard
if Delay_Count = 1 or else First_Delay then
First_Delay := False;
Delay_Alt := New_List (
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (Delay_Min, Loc),
Expression => Expression (Delay_Statement (Alt))));
if Delay_Count > 1 then
Append_To (Delay_Alt,
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (Delay_Index, Loc),
Expression => Make_Integer_Literal (Loc, Index)));
end if;
else
Delay_Alt := New_List (
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (Delay_Val, Loc),
Expression => Expression (Delay_Statement (Alt))));
if Time_Type = Standard_Duration then
Cond :=
Make_Op_Lt (Loc,
Left_Opnd => New_Occurrence_Of (Delay_Val, Loc),
Right_Opnd => New_Occurrence_Of (Delay_Min, Loc));
else
-- The scope of the time type must define a comparison
-- operator. The scope itself may not be visible, so we
-- construct a node with entity information to insure that
-- semantic analysis can find the proper operator.
Cond :=
Make_Function_Call (Loc,
Name => Make_Selected_Component (Loc,
Prefix =>
New_Occurrence_Of (Scope (Time_Type), Loc),
Selector_Name =>
Make_Operator_Symbol (Loc,
Chars => Name_Op_Lt,
Strval => No_String)),
Parameter_Associations =>
New_List (
New_Occurrence_Of (Delay_Val, Loc),
New_Occurrence_Of (Delay_Min, Loc)));
Set_Entity (Prefix (Name (Cond)), Scope (Time_Type));
end if;
Append_To (Delay_Alt,
Make_Implicit_If_Statement (N,
Condition => Cond,
Then_Statements => New_List (
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (Delay_Min, Loc),
Expression => New_Occurrence_Of (Delay_Val, Loc)),
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (Delay_Index, Loc),
Expression => Make_Integer_Literal (Loc, Index)))));
end if;
if Check_Guard then
Append_To (Delay_Alt,
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (Guard_Open, Loc),
Expression => New_Occurrence_Of (Standard_True, Loc)));
end if;
if Present (Condition (Alt)) then
Delay_Alt := New_List (
Make_Implicit_If_Statement (N,
Condition => Condition (Alt),
Then_Statements => Delay_Alt));
end if;
Append_List (Delay_Alt, Delay_List);
Ensure_Statement_Present (Dloc, Alt);
-- If the delay alternative has a statement part, add choice to the
-- case statements for delays.
if not Is_Empty_List (Statements (Alt)) then
if Delay_Count = 1 then
Append_List (Statements (Alt), Delay_Alt_List);
else
Append_To (Delay_Alt_List,
Make_Case_Statement_Alternative (Loc,
Discrete_Choices => New_List (
Make_Integer_Literal (Loc, Index)),
Statements => Statements (Alt)));
end if;
elsif Delay_Count = 1 then
-- If the single delay has no trailing statements, add a branch
-- to the exit label to the selective wait.
Delay_Alt_List := New_List (
Make_Goto_Statement (Loc,
Name => New_Copy (Identifier (End_Lab))));
end if;
end Process_Delay_Alternative;
-- Start of processing for Expand_N_Selective_Accept
begin
Process_Statements_For_Controlled_Objects (N);
-- First insert some declarations before the select. The first is:
-- Ann : Address
-- This variable holds the parameters passed to the accept body. This
-- declaration has already been inserted by the time we get here by
-- a call to Expand_Accept_Declarations made from the semantics when
-- processing the first accept statement contained in the select. We
-- can find this entity as Accept_Address (E), where E is any of the
-- entries references by contained accept statements.
-- The first step is to scan the list of Selective_Accept_Statements
-- to find this entity, and also count the number of accepts, and
-- determine if terminated, delay or else is present:
Num_Alts := 0;
Alt := First (Alts);
while Present (Alt) loop
Process_Statements_For_Controlled_Objects (Alt);
if Nkind (Alt) = N_Accept_Alternative then
Add_Accept (Alt);
elsif Nkind (Alt) = N_Delay_Alternative then
Delay_Count := Delay_Count + 1;
-- If the delays are relative delays, the delay expressions have
-- type Standard_Duration. Otherwise they must have some time type
-- recognized by GNAT.
if Nkind (Delay_Statement (Alt)) = N_Delay_Relative_Statement then
Time_Type := Standard_Duration;
else
Time_Type := Etype (Expression (Delay_Statement (Alt)));
if Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time)
or else Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time)
then
null;
else
-- Move this check to sem???
Error_Msg_NE (
"& is not a time type (RM 9.6(6))",
Expression (Delay_Statement (Alt)), Time_Type);
Time_Type := Standard_Duration;
Set_Etype (Expression (Delay_Statement (Alt)), Any_Type);
end if;
end if;
if No (Condition (Alt)) then
-- This guard will always be open
Check_Guard := False;
end if;
elsif Nkind (Alt) = N_Terminate_Alternative then
Adjust_Condition (Condition (Alt));
Terminate_Alt := Alt;
end if;
Num_Alts := Num_Alts + 1;
Next (Alt);
end loop;
Else_Present := Present (Else_Statements (N));
-- At the same time (see procedure Add_Accept) we build the accept list:
-- Qnn : Accept_List (1 .. num-select) := (
-- (null-body, entry-index),
-- (null-body, entry-index),
-- ..
-- (null_body, entry-index));
-- In the above declaration, null-body is True if the corresponding
-- accept has no body, and false otherwise. The entry is either the
-- entry index expression if there is no guard, or if a guard is
-- present, then an if expression of the form:
-- (if guard then entry-index else Null_Task_Entry)
-- If a guard is statically known to be false, the entry can simply
-- be omitted from the accept list.
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => Qnam,
Object_Definition => New_Occurrence_Of (RTE (RE_Accept_List), Loc),
Aliased_Present => True,
Expression =>
Make_Qualified_Expression (Loc,
Subtype_Mark =>
New_Occurrence_Of (RTE (RE_Accept_List), Loc),
Expression =>
Make_Aggregate (Loc, Expressions => Accept_List))));
-- Then we declare the variable that holds the index for the accept
-- that will be selected for service:
-- Xnn : Select_Index;
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => Xnam,
Object_Definition =>
New_Occurrence_Of (RTE (RE_Select_Index), Loc),
Expression =>
New_Occurrence_Of (RTE (RE_No_Rendezvous), Loc)));
-- After this follow procedure declarations for each accept body
-- procedure Pnn is
-- begin
-- ...
-- end;
-- where the ... are statements from the corresponding procedure body.
-- No parameters are involved, since the parameters are passed via Ann
-- and the parameter references have already been expanded to be direct
-- references to Ann (see Exp_Ch2.Expand_Entry_Parameter). Furthermore,
-- any embedded tasking statements (which would normally be illegal in
-- procedures), have been converted to calls to the tasking runtime so
-- there is no problem in putting them into procedures.
-- The original accept statement has been expanded into a block in
-- the same fashion as for simple accepts (see Build_Accept_Body).
-- Note: we don't really need to build these procedures for the case
-- where no delay statement is present, but it is just as easy to
-- build them unconditionally, and not significantly inefficient,
-- since if they are short they will be inlined anyway.
-- The procedure declarations have been assembled in Body_List
-- If delays are present, we must compute the required delay.
-- We first generate the declarations:
-- Delay_Index : Boolean := 0;
-- Delay_Min : Some_Time_Type.Time;
-- Delay_Val : Some_Time_Type.Time;
-- Delay_Index will be set to the index of the minimum delay, i.e. the
-- active delay that is actually chosen as the basis for the possible
-- delay if an immediate rendez-vous is not possible.
-- In the most common case there is a single delay statement, and this
-- is handled specially.
if Delay_Count > 0 then
-- Generate the required declarations
Delay_Val :=
Make_Defining_Identifier (Loc, New_External_Name ('D', 1));
Delay_Index :=
Make_Defining_Identifier (Loc, New_External_Name ('D', 2));
Delay_Min :=
Make_Defining_Identifier (Loc, New_External_Name ('D', 3));
pragma Assert (Present (Time_Type));
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => Delay_Val,
Object_Definition => New_Occurrence_Of (Time_Type, Loc)));
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => Delay_Index,
Object_Definition => New_Occurrence_Of (Standard_Integer, Loc),
Expression => Make_Integer_Literal (Loc, 0)));
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => Delay_Min,
Object_Definition => New_Occurrence_Of (Time_Type, Loc),
Expression =>
Unchecked_Convert_To (Time_Type,
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Underlying_Type (Time_Type), Loc),
Attribute_Name => Name_Last))));
-- Create Duration and Delay_Mode objects used for passing a delay
-- value to RTS
D := Make_Temporary (Loc, 'D');
M := Make_Temporary (Loc, 'M');
declare
Discr : Entity_Id;
begin
-- Note that these values are defined in s-osprim.ads and must
-- be kept in sync:
--
-- Relative : constant := 0;
-- Absolute_Calendar : constant := 1;
-- Absolute_RT : constant := 2;
if Time_Type = Standard_Duration then
Discr := Make_Integer_Literal (Loc, 0);
elsif Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time) then
Discr := Make_Integer_Literal (Loc, 1);
else
pragma Assert
(Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time));
Discr := Make_Integer_Literal (Loc, 2);
end if;
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => D,
Object_Definition =>
New_Occurrence_Of (Standard_Duration, Loc)));
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => M,
Object_Definition =>
New_Occurrence_Of (Standard_Integer, Loc),
Expression => Discr));
end;
if Check_Guard then
Guard_Open :=
Make_Defining_Identifier (Loc, New_External_Name ('G', 1));
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => Guard_Open,
Object_Definition =>
New_Occurrence_Of (Standard_Boolean, Loc),
Expression =>
New_Occurrence_Of (Standard_False, Loc)));
end if;
-- Delay_Count is zero, don't need M and D set (suppress warning)
else
M := Empty;
D := Empty;
end if;
if Present (Terminate_Alt) then
-- If the terminate alternative guard is False, use
-- Simple_Mode; otherwise use Terminate_Mode.
if Present (Condition (Terminate_Alt)) then
Select_Mode := Make_If_Expression (Loc,
New_List (Condition (Terminate_Alt),
New_Occurrence_Of (RTE (RE_Terminate_Mode), Loc),
New_Occurrence_Of (RTE (RE_Simple_Mode), Loc)));
else
Select_Mode := New_Occurrence_Of (RTE (RE_Terminate_Mode), Loc);
end if;
elsif Else_Present or Delay_Count > 0 then
Select_Mode := New_Occurrence_Of (RTE (RE_Else_Mode), Loc);
else
Select_Mode := New_Occurrence_Of (RTE (RE_Simple_Mode), Loc);
end if;
Select_Call := Make_Select_Call (Select_Mode);
Append (Select_Call, Stats);
-- Now generate code to act on the result. There is an entry
-- in this case for each accept statement with a non-null body,
-- followed by a branch to the statements that follow the Accept.
-- In the absence of delay alternatives, we generate:
-- case X is
-- when No_Rendezvous => -- omitted if simple mode
-- goto Lab0;
-- when 1 =>
-- P1n;
-- goto Lab1;
-- when 2 =>
-- P2n;
-- goto Lab2;
-- when others =>
-- goto Exit;
-- end case;
--
-- Lab0: Else_Statements;
-- goto exit;
-- Lab1: Trailing_Statements1;
-- goto Exit;
--
-- Lab2: Trailing_Statements2;
-- goto Exit;
-- ...
-- Exit:
-- Generate label for common exit
End_Lab := Make_And_Declare_Label (Num_Alts + 1);
-- First entry is the default case, when no rendezvous is possible
Choices := New_List (New_Occurrence_Of (RTE (RE_No_Rendezvous), Loc));
if Else_Present then
-- If no rendezvous is possible, the else part is executed
Lab := Make_And_Declare_Label (0);
Alt_Stats := New_List (
Make_Goto_Statement (Loc,
Name => New_Copy (Identifier (Lab))));
Append (Lab, Trailing_List);
Append_List (Else_Statements (N), Trailing_List);
Append_To (Trailing_List,
Make_Goto_Statement (Loc,
Name => New_Copy (Identifier (End_Lab))));
else
Alt_Stats := New_List (
Make_Goto_Statement (Loc,
Name => New_Copy (Identifier (End_Lab))));
end if;
Append_To (Alt_List,
Make_Case_Statement_Alternative (Loc,
Discrete_Choices => Choices,
Statements => Alt_Stats));
-- We make use of the fact that Accept_Index is an integer type, and
-- generate successive literals for entries for each accept. Only those
-- for which there is a body or trailing statements get a case entry.
Alt := First (Select_Alternatives (N));
Proc := First (Body_List);
while Present (Alt) loop
if Nkind (Alt) = N_Accept_Alternative then
Process_Accept_Alternative (Alt, Index, Proc);
Index := Index + 1;
if Present
(Handled_Statement_Sequence (Accept_Statement (Alt)))
then
Next (Proc);
end if;
elsif Nkind (Alt) = N_Delay_Alternative then
Process_Delay_Alternative (Alt, Delay_Num);
Delay_Num := Delay_Num + 1;
end if;
Next (Alt);
end loop;
-- An others choice is always added to the main case, as well
-- as the delay case (to satisfy the compiler).
Append_To (Alt_List,
Make_Case_Statement_Alternative (Loc,
Discrete_Choices =>
New_List (Make_Others_Choice (Loc)),
Statements =>
New_List (Make_Goto_Statement (Loc,
Name => New_Copy (Identifier (End_Lab))))));
Accept_Case := New_List (
Make_Case_Statement (Loc,
Expression => New_Occurrence_Of (Xnam, Loc),
Alternatives => Alt_List));
Append_List (Trailing_List, Accept_Case);
Append_List (Body_List, Decls);
-- Construct case statement for trailing statements of delay
-- alternatives, if there are several of them.
if Delay_Count > 1 then
Append_To (Delay_Alt_List,
Make_Case_Statement_Alternative (Loc,
Discrete_Choices =>
New_List (Make_Others_Choice (Loc)),
Statements =>
New_List (Make_Null_Statement (Loc))));
Delay_Case := New_List (
Make_Case_Statement (Loc,
Expression => New_Occurrence_Of (Delay_Index, Loc),
Alternatives => Delay_Alt_List));
else
Delay_Case := Delay_Alt_List;
end if;
-- If there are no delay alternatives, we append the case statement
-- to the statement list.
if Delay_Count = 0 then
Append_List (Accept_Case, Stats);
-- Delay alternatives present
else
-- If delay alternatives are present we generate:
-- find minimum delay.
-- DX := minimum delay;
-- M := <delay mode>;
-- Timed_Selective_Wait (Q'Unchecked_Access, Delay_Mode, P,
-- DX, MX, X);
--
-- if X = No_Rendezvous then
-- case statement for delay statements.
-- else
-- case statement for accept alternatives.
-- end if;
declare
Cases : Node_Id;
Stmt : Node_Id;
Parms : List_Id;
Parm : Node_Id;
Conv : Node_Id;
begin
-- The type of the delay expression is known to be legal
if Time_Type = Standard_Duration then
Conv := New_Occurrence_Of (Delay_Min, Loc);
elsif Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time) then
Conv := Make_Function_Call (Loc,
New_Occurrence_Of (RTE (RO_CA_To_Duration), Loc),
New_List (New_Occurrence_Of (Delay_Min, Loc)));
else
pragma Assert
(Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time));
Conv := Make_Function_Call (Loc,
New_Occurrence_Of (RTE (RO_RT_To_Duration), Loc),
New_List (New_Occurrence_Of (Delay_Min, Loc)));
end if;
Stmt := Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (D, Loc),
Expression => Conv);
-- Change the value for Accept_Modes. (Else_Mode -> Delay_Mode)
Parms := Parameter_Associations (Select_Call);
Parm := First (Parms);
while Present (Parm) and then Parm /= Select_Mode loop
Next (Parm);
end loop;
pragma Assert (Present (Parm));
Rewrite (Parm, New_Occurrence_Of (RTE (RE_Delay_Mode), Loc));
Analyze (Parm);
-- Prepare two new parameters of Duration and Delay_Mode type
-- which represent the value and the mode of the minimum delay.
Next (Parm);
Insert_After (Parm, New_Occurrence_Of (M, Loc));
Insert_After (Parm, New_Occurrence_Of (D, Loc));
-- Create a call to RTS
Rewrite (Select_Call,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Timed_Selective_Wait), Loc),
Parameter_Associations => Parms));
-- This new call should follow the calculation of the minimum
-- delay.
Insert_List_Before (Select_Call, Delay_List);
if Check_Guard then
Stmt :=
Make_Implicit_If_Statement (N,
Condition => New_Occurrence_Of (Guard_Open, Loc),
Then_Statements => New_List (
New_Copy_Tree (Stmt),
New_Copy_Tree (Select_Call)),
Else_Statements => Accept_Or_Raise);
Rewrite (Select_Call, Stmt);
else
Insert_Before (Select_Call, Stmt);
end if;
Cases :=
Make_Implicit_If_Statement (N,
Condition => Make_Op_Eq (Loc,
Left_Opnd => New_Occurrence_Of (Xnam, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_No_Rendezvous), Loc)),
Then_Statements => Delay_Case,
Else_Statements => Accept_Case);
Append (Cases, Stats);
end;
end if;
Append (End_Lab, Stats);
-- Replace accept statement with appropriate block
Rewrite (N,
Make_Block_Statement (Loc,
Declarations => Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Statements => Stats)));
Analyze (N);
-- Note: have to worry more about abort deferral in above code ???
-- Final step is to unstack the Accept_Address entries for all accept
-- statements appearing in accept alternatives in the select statement
Alt := First (Alts);
while Present (Alt) loop
if Nkind (Alt) = N_Accept_Alternative then
Remove_Last_Elmt (Accept_Address
(Entity (Entry_Direct_Name (Accept_Statement (Alt)))));
end if;
Next (Alt);
end loop;
end Expand_N_Selective_Accept;
-------------------------------------------
-- Expand_N_Single_Protected_Declaration --
-------------------------------------------
-- A single protected declaration should never be present after semantic
-- analysis because it is transformed into a protected type declaration
-- and an accompanying anonymous object. This routine ensures that the
-- transformation takes place.
procedure Expand_N_Single_Protected_Declaration (N : Node_Id) is
begin
raise Program_Error;
end Expand_N_Single_Protected_Declaration;
--------------------------------------
-- Expand_N_Single_Task_Declaration --
--------------------------------------
-- A single task declaration should never be present after semantic
-- analysis because it is transformed into a task type declaration and
-- an accompanying anonymous object. This routine ensures that the
-- transformation takes place.
procedure Expand_N_Single_Task_Declaration (N : Node_Id) is
begin
raise Program_Error;
end Expand_N_Single_Task_Declaration;
------------------------
-- Expand_N_Task_Body --
------------------------
-- Given a task body
-- task body tname is
-- <declarations>
-- begin
-- <statements>
-- end x;
-- This expansion routine converts it into a procedure and sets the
-- elaboration flag for the procedure to true, to represent the fact
-- that the task body is now elaborated:
-- procedure tnameB (_Task : access tnameV) is
-- discriminal : dtype renames _Task.discriminant;
-- procedure _clean is
-- begin
-- Abort_Defer.all;
-- Complete_Task;
-- Abort_Undefer.all;
-- return;
-- end _clean;
-- begin
-- Abort_Undefer.all;
-- <declarations>
-- System.Task_Stages.Complete_Activation;
-- <statements>
-- at end
-- _clean;
-- end tnameB;
-- tnameE := True;
-- In addition, if the task body is an activator, then a call to activate
-- tasks is added at the start of the statements, before the call to
-- Complete_Activation, and if in addition the task is a master then it
-- must be established as a master. These calls are inserted and analyzed
-- in Expand_Cleanup_Actions, when the Handled_Sequence_Of_Statements is
-- expanded.
-- There is one discriminal declaration line generated for each
-- discriminant that is present to provide an easy reference point for
-- discriminant references inside the body (see Exp_Ch2.Expand_Name).
-- Note on relationship to GNARLI definition. In the GNARLI definition,
-- task body procedures have a profile (Arg : System.Address). That is
-- needed because GNARLI has to use the same access-to-subprogram type
-- for all task types. We depend here on knowing that in GNAT, passing
-- an address argument by value is identical to passing a record value
-- by access (in either case a single pointer is passed), so even though
-- this procedure has the wrong profile. In fact it's all OK, since the
-- callings sequence is identical.
procedure Expand_N_Task_Body (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Ttyp : constant Entity_Id := Corresponding_Spec (N);
Call : Node_Id;
New_N : Node_Id;
Insert_Nod : Node_Id;
-- Used to determine the proper location of wrapper body insertions
begin
-- if no task body procedure, means we had an error in configurable
-- run-time mode, and there is no point in proceeding further.
if No (Task_Body_Procedure (Ttyp)) then
return;
end if;
-- Add renaming declarations for discriminals and a declaration for the
-- entry family index (if applicable).
Install_Private_Data_Declarations
(Loc, Task_Body_Procedure (Ttyp), Ttyp, N, Declarations (N));
-- Add a call to Abort_Undefer at the very beginning of the task
-- body since this body is called with abort still deferred.
if Abort_Allowed then
Call := Build_Runtime_Call (Loc, RE_Abort_Undefer);
Insert_Before
(First (Statements (Handled_Statement_Sequence (N))), Call);
Analyze (Call);
end if;
-- The statement part has already been protected with an at_end and
-- cleanup actions. The call to Complete_Activation must be placed
-- at the head of the sequence of statements of that block. The
-- declarations have been merged in this sequence of statements but
-- the first real statement is accessible from the First_Real_Statement
-- field (which was set for exactly this purpose).
if Restricted_Profile then
Call := Build_Runtime_Call (Loc, RE_Complete_Restricted_Activation);
else
Call := Build_Runtime_Call (Loc, RE_Complete_Activation);
end if;
Insert_Before
(First_Real_Statement (Handled_Statement_Sequence (N)), Call);
Analyze (Call);
New_N :=
Make_Subprogram_Body (Loc,
Specification => Build_Task_Proc_Specification (Ttyp),
Declarations => Declarations (N),
Handled_Statement_Sequence => Handled_Statement_Sequence (N));
Set_Is_Task_Body_Procedure (New_N);
-- If the task contains generic instantiations, cleanup actions are
-- delayed until after instantiation. Transfer the activation chain to
-- the subprogram, to insure that the activation call is properly
-- generated. It the task body contains inner tasks, indicate that the
-- subprogram is a task master.
if Delay_Cleanups (Ttyp) then
Set_Activation_Chain_Entity (New_N, Activation_Chain_Entity (N));
Set_Is_Task_Master (New_N, Is_Task_Master (N));
end if;
Rewrite (N, New_N);
Analyze (N);
-- Set elaboration flag immediately after task body. If the body is a
-- subunit, the flag is set in the declarative part containing the stub.
if Nkind (Parent (N)) /= N_Subunit then
Insert_After (N,
Make_Assignment_Statement (Loc,
Name =>
Make_Identifier (Loc, New_External_Name (Chars (Ttyp), 'E')),
Expression => New_Occurrence_Of (Standard_True, Loc)));
end if;
-- Ada 2005 (AI-345): Construct the primitive entry wrapper bodies after
-- the task body. At this point all wrapper specs have been created,
-- frozen and included in the dispatch table for the task type.
if Ada_Version >= Ada_2005 then
if Nkind (Parent (N)) = N_Subunit then
Insert_Nod := Corresponding_Stub (Parent (N));
else
Insert_Nod := N;
end if;
Build_Wrapper_Bodies (Loc, Ttyp, Insert_Nod);
end if;
end Expand_N_Task_Body;
------------------------------------
-- Expand_N_Task_Type_Declaration --
------------------------------------
-- We have several things to do. First we must create a Boolean flag used
-- to mark if the body is elaborated yet. This variable gets set to True
-- when the body of the task is elaborated (we can't rely on the normal
-- ABE mechanism for the task body, since we need to pass an access to
-- this elaboration boolean to the runtime routines).
-- taskE : aliased Boolean := False;
-- Next a variable is declared to hold the task stack size (either the
-- default : Unspecified_Size, or a value that is set by a pragma
-- Storage_Size). If the value of the pragma Storage_Size is static, then
-- the variable is initialized with this value:
-- taskZ : Size_Type := Unspecified_Size;
-- or
-- taskZ : Size_Type := Size_Type (size_expression);
-- Note: No variable is needed to hold the task relative deadline since
-- its value would never be static because the parameter is of a private
-- type (Ada.Real_Time.Time_Span).
-- Next we create a corresponding record type declaration used to represent
-- values of this task. The general form of this type declaration is
-- type taskV (discriminants) is record
-- _Task_Id : Task_Id;
-- entry_family : array (bounds) of Void;
-- _Priority : Integer := priority_expression;
-- _Size : Size_Type := size_expression;
-- _Secondary_Stack_Size : Size_Type := size_expression;
-- _Task_Info : Task_Info_Type := task_info_expression;
-- _CPU : Integer := cpu_range_expression;
-- _Relative_Deadline : Time_Span := time_span_expression;
-- _Domain : Dispatching_Domain := dd_expression;
-- end record;
-- The discriminants are present only if the corresponding task type has
-- discriminants, and they exactly mirror the task type discriminants.
-- The Id field is always present. It contains the Task_Id value, as set by
-- the call to Create_Task. Note that although the task is limited, the
-- task value record type is not limited, so there is no problem in passing
-- this field as an out parameter to Create_Task.
-- One entry_family component is present for each entry family in the task
-- definition. The bounds correspond to the bounds of the entry family
-- (which may depend on discriminants). The element type is void, since we
-- only need the bounds information for determining the entry index. Note
-- that the use of an anonymous array would normally be illegal in this
-- context, but this is a parser check, and the semantics is quite prepared
-- to handle such a case.
-- The _Size field is present only if a Storage_Size pragma appears in the
-- task definition. The expression captures the argument that was present
-- in the pragma, and is used to override the task stack size otherwise
-- associated with the task type.
-- The _Secondary_Stack_Size field is present only the task entity has a
-- Secondary_Stack_Size rep item. It will be filled at the freeze point,
-- when the record init proc is built, to capture the expression of the
-- rep item (see Build_Record_Init_Proc in Exp_Ch3). Note that it cannot
-- be filled here since aspect evaluations are delayed till the freeze
-- point.
-- The _Priority field is present only if the task entity has a Priority or
-- Interrupt_Priority rep item (pragma, aspect specification or attribute
-- definition clause). It will be filled at the freeze point, when the
-- record init proc is built, to capture the expression of the rep item
-- (see Build_Record_Init_Proc in Exp_Ch3). Note that it cannot be filled
-- here since aspect evaluations are delayed till the freeze point.
-- The _Task_Info field is present only if a Task_Info pragma appears in
-- the task definition. The expression captures the argument that was
-- present in the pragma, and is used to provide the Task_Image parameter
-- to the call to Create_Task.
-- The _CPU field is present only if the task entity has a CPU rep item
-- (pragma, aspect specification or attribute definition clause). It will
-- be filled at the freeze point, when the record init proc is built, to
-- capture the expression of the rep item (see Build_Record_Init_Proc in
-- Exp_Ch3). Note that it cannot be filled here since aspect evaluations
-- are delayed till the freeze point.
-- The _Relative_Deadline field is present only if a Relative_Deadline
-- pragma appears in the task definition. The expression captures the
-- argument that was present in the pragma, and is used to provide the
-- Relative_Deadline parameter to the call to Create_Task.
-- The _Domain field is present only if the task entity has a
-- Dispatching_Domain rep item (pragma, aspect specification or attribute
-- definition clause). It will be filled at the freeze point, when the
-- record init proc is built, to capture the expression of the rep item
-- (see Build_Record_Init_Proc in Exp_Ch3). Note that it cannot be filled
-- here since aspect evaluations are delayed till the freeze point.
-- When a task is declared, an instance of the task value record is
-- created. The elaboration of this declaration creates the correct bounds
-- for the entry families, and also evaluates the size, priority, and
-- task_Info expressions if needed. The initialization routine for the task
-- type itself then calls Create_Task with appropriate parameters to
-- initialize the value of the Task_Id field.
-- Note: the address of this record is passed as the "Discriminants"
-- parameter for Create_Task. Since Create_Task merely passes this onto the
-- body procedure, it does not matter that it does not quite match the
-- GNARLI model of what is being passed (the record contains more than just
-- the discriminants, but the discriminants can be found from the record
-- value).
-- The Entity_Id for this created record type is placed in the
-- Corresponding_Record_Type field of the associated task type entity.
-- Next we create a procedure specification for the task body procedure:
-- procedure taskB (_Task : access taskV);
-- Note that this must come after the record type declaration, since
-- the spec refers to this type. It turns out that the initialization
-- procedure for the value type references the task body spec, but that's
-- fine, since it won't be generated till the freeze point for the type,
-- which is certainly after the task body spec declaration.
-- Finally, we set the task index value field of the entry attribute in
-- the case of a simple entry.
procedure Expand_N_Task_Type_Declaration (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
TaskId : constant Entity_Id := Defining_Identifier (N);
Tasktyp : constant Entity_Id := Etype (Defining_Identifier (N));
Tasknm : constant Name_Id := Chars (Tasktyp);
Taskdef : constant Node_Id := Task_Definition (N);
Body_Decl : Node_Id;
Cdecls : List_Id;
Decl_Stack : Node_Id;
Decl_SS : Node_Id;
Elab_Decl : Node_Id;
Ent_Stack : Entity_Id;
Proc_Spec : Node_Id;
Rec_Decl : Node_Id;
Rec_Ent : Entity_Id;
Size_Decl : Entity_Id;
Task_Size : Node_Id;
function Get_Relative_Deadline_Pragma (T : Node_Id) return Node_Id;
-- Searches the task definition T for the first occurrence of the pragma
-- Relative Deadline. The caller has ensured that the pragma is present
-- in the task definition. Note that this routine cannot be implemented
-- with the Rep Item chain mechanism since Relative_Deadline pragmas are
-- not chained because their expansion into a procedure call statement
-- would cause a break in the chain.
----------------------------------
-- Get_Relative_Deadline_Pragma --
----------------------------------
function Get_Relative_Deadline_Pragma (T : Node_Id) return Node_Id is
N : Node_Id;
begin
N := First (Visible_Declarations (T));
while Present (N) loop
if Nkind (N) = N_Pragma
and then Pragma_Name (N) = Name_Relative_Deadline
then
return N;
end if;
Next (N);
end loop;
N := First (Private_Declarations (T));
while Present (N) loop
if Nkind (N) = N_Pragma
and then Pragma_Name (N) = Name_Relative_Deadline
then
return N;
end if;
Next (N);
end loop;
raise Program_Error;
end Get_Relative_Deadline_Pragma;
-- Start of processing for Expand_N_Task_Type_Declaration
begin
-- If already expanded, nothing to do
if Present (Corresponding_Record_Type (Tasktyp)) then
return;
end if;
-- Here we will do the expansion
Rec_Decl := Build_Corresponding_Record (N, Tasktyp, Loc);
Rec_Ent := Defining_Identifier (Rec_Decl);
Cdecls := Component_Items (Component_List
(Type_Definition (Rec_Decl)));
Qualify_Entity_Names (N);
-- First create the elaboration variable
Elab_Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Sloc (Tasktyp),
Chars => New_External_Name (Tasknm, 'E')),
Aliased_Present => True,
Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc),
Expression => New_Occurrence_Of (Standard_False, Loc));
Insert_After (N, Elab_Decl);
-- Next create the declaration of the size variable (tasknmZ)
Set_Storage_Size_Variable (Tasktyp,
Make_Defining_Identifier (Sloc (Tasktyp),
Chars => New_External_Name (Tasknm, 'Z')));
if Present (Taskdef)
and then Has_Storage_Size_Pragma (Taskdef)
and then
Is_OK_Static_Expression
(Expression
(First (Pragma_Argument_Associations
(Get_Rep_Pragma (TaskId, Name_Storage_Size)))))
then
Size_Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Storage_Size_Variable (Tasktyp),
Object_Definition =>
New_Occurrence_Of (RTE (RE_Size_Type), Loc),
Expression =>
Convert_To (RTE (RE_Size_Type),
Relocate_Node
(Expression (First (Pragma_Argument_Associations
(Get_Rep_Pragma
(TaskId, Name_Storage_Size)))))));
else
Size_Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Storage_Size_Variable (Tasktyp),
Object_Definition =>
New_Occurrence_Of (RTE (RE_Size_Type), Loc),
Expression =>
New_Occurrence_Of (RTE (RE_Unspecified_Size), Loc));
end if;
Insert_After (Elab_Decl, Size_Decl);
-- Next build the rest of the corresponding record declaration. This is
-- done last, since the corresponding record initialization procedure
-- will reference the previously created entities.
-- Fill in the component declarations -- first the _Task_Id field
Append_To (Cdecls,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uTask_Id),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication => New_Occurrence_Of (RTE (RO_ST_Task_Id),
Loc))));
-- Declare static ATCB (that is, created by the expander) if we are
-- using the Restricted run time.
if Restricted_Profile then
Append_To (Cdecls,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uATCB),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => True,
Subtype_Indication => Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of (RTE (RE_Ada_Task_Control_Block), Loc),
Constraint =>
Make_Index_Or_Discriminant_Constraint (Loc,
Constraints =>
New_List (Make_Integer_Literal (Loc, 0)))))));
end if;
-- Declare static stack (that is, created by the expander) if we are
-- using the Restricted run time on a bare board configuration.
if Restricted_Profile and then Preallocated_Stacks_On_Target then
-- First we need to extract the appropriate stack size
Ent_Stack := Make_Defining_Identifier (Loc, Name_uStack);
if Present (Taskdef) and then Has_Storage_Size_Pragma (Taskdef) then
declare
Expr_N : constant Node_Id :=
Expression (First (
Pragma_Argument_Associations (
Get_Rep_Pragma (TaskId, Name_Storage_Size))));
Etyp : constant Entity_Id := Etype (Expr_N);
P : constant Node_Id := Parent (Expr_N);
begin
-- The stack is defined inside the corresponding record.
-- Therefore if the size of the stack is set by means of
-- a discriminant, we must reference the discriminant of the
-- corresponding record type.
if Nkind (Expr_N) in N_Has_Entity
and then Present (Discriminal_Link (Entity (Expr_N)))
then
Task_Size :=
New_Occurrence_Of
(CR_Discriminant (Discriminal_Link (Entity (Expr_N))),
Loc);
Set_Parent (Task_Size, P);
Set_Etype (Task_Size, Etyp);
Set_Analyzed (Task_Size);
else
Task_Size := New_Copy_Tree (Expr_N);
end if;
end;
else
Task_Size :=
New_Occurrence_Of (RTE (RE_Default_Stack_Size), Loc);
end if;
Decl_Stack := Make_Component_Declaration (Loc,
Defining_Identifier => Ent_Stack,
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => True,
Subtype_Indication => Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of (RTE (RE_Storage_Array), Loc),
Constraint =>
Make_Index_Or_Discriminant_Constraint (Loc,
Constraints => New_List (Make_Range (Loc,
Low_Bound => Make_Integer_Literal (Loc, 1),
High_Bound => Convert_To (RTE (RE_Storage_Offset),
Task_Size)))))));
Append_To (Cdecls, Decl_Stack);
-- The appropriate alignment for the stack is ensured by the run-time
-- code in charge of task creation.
end if;
-- Declare a static secondary stack if the conditions for a statically
-- generated stack are met.
if Create_Secondary_Stack_For_Task (TaskId) then
declare
Size_Expr : constant Node_Id :=
Expression (First (
Pragma_Argument_Associations (
Get_Rep_Pragma (TaskId,
Name_Secondary_Stack_Size))));
Stack_Size : Node_Id;
begin
-- The secondary stack is defined inside the corresponding
-- record. Therefore if the size of the stack is set by means
-- of a discriminant, we must reference the discriminant of the
-- corresponding record type.
if Nkind (Size_Expr) in N_Has_Entity
and then Present (Discriminal_Link (Entity (Size_Expr)))
then
Stack_Size :=
New_Occurrence_Of
(CR_Discriminant (Discriminal_Link (Entity (Size_Expr))),
Loc);
Set_Parent (Stack_Size, Parent (Size_Expr));
Set_Etype (Stack_Size, Etype (Size_Expr));
Set_Analyzed (Stack_Size);
else
Stack_Size := New_Copy_Tree (Size_Expr);
end if;
-- Create the secondary stack for the task
Decl_SS :=
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uSecondary_Stack),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => True,
Subtype_Indication =>
Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of (RTE (RE_SS_Stack), Loc),
Constraint =>
Make_Index_Or_Discriminant_Constraint (Loc,
Constraints => New_List (
Convert_To (RTE (RE_Size_Type),
Stack_Size))))));
Append_To (Cdecls, Decl_SS);
end;
end if;
-- Add components for entry families
Collect_Entry_Families (Loc, Cdecls, Size_Decl, Tasktyp);
-- Add the _Priority component if a Interrupt_Priority or Priority rep
-- item is present.
if Has_Rep_Item (TaskId, Name_Priority, Check_Parents => False) then
Append_To (Cdecls,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uPriority),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication =>
New_Occurrence_Of (Standard_Integer, Loc))));
end if;
-- Add the _Size component if a Storage_Size pragma is present
if Present (Taskdef) and then Has_Storage_Size_Pragma (Taskdef) then
Append_To (Cdecls,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uSize),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication =>
New_Occurrence_Of (RTE (RE_Size_Type), Loc)),
Expression =>
Convert_To (RTE (RE_Size_Type),
New_Copy_Tree (
Expression (First (
Pragma_Argument_Associations (
Get_Rep_Pragma (TaskId, Name_Storage_Size))))))));
end if;
-- Add the _Secondary_Stack_Size component if a Secondary_Stack_Size
-- pragma is present.
if Has_Rep_Pragma
(TaskId, Name_Secondary_Stack_Size, Check_Parents => False)
then
Append_To (Cdecls,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uSecondary_Stack_Size),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication =>
New_Occurrence_Of (RTE (RE_Size_Type), Loc))));
end if;
-- Add the _Task_Info component if a Task_Info pragma is present
if Has_Rep_Pragma (TaskId, Name_Task_Info, Check_Parents => False) then
Append_To (Cdecls,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uTask_Info),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication =>
New_Occurrence_Of (RTE (RE_Task_Info_Type), Loc)),
Expression => New_Copy (
Expression (First (
Pragma_Argument_Associations (
Get_Rep_Pragma
(TaskId, Name_Task_Info, Check_Parents => False)))))));
end if;
-- Add the _CPU component if a CPU rep item is present
if Has_Rep_Item (TaskId, Name_CPU, Check_Parents => False) then
Append_To (Cdecls,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uCPU),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication =>
New_Occurrence_Of (RTE (RE_CPU_Range), Loc))));
end if;
-- Add the _Relative_Deadline component if a Relative_Deadline pragma is
-- present. If we are using a restricted run time this component will
-- not be added (deadlines are not allowed by the Ravenscar profile),
-- unless the task dispatching policy is EDF (for GNAT_Ravenscar_EDF
-- profile).
if (not Restricted_Profile or else Task_Dispatching_Policy = 'E')
and then Present (Taskdef)
and then Has_Relative_Deadline_Pragma (Taskdef)
then
Append_To (Cdecls,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uRelative_Deadline),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication =>
New_Occurrence_Of (RTE (RE_Time_Span), Loc)),
Expression =>
Convert_To (RTE (RE_Time_Span),
New_Copy_Tree (
Expression (First (
Pragma_Argument_Associations (
Get_Relative_Deadline_Pragma (Taskdef))))))));
end if;
-- Add the _Dispatching_Domain component if a Dispatching_Domain rep
-- item is present. If we are using a restricted run time this component
-- will not be added (dispatching domains are not allowed by the
-- Ravenscar profile).
if not Restricted_Profile
and then
Has_Rep_Item
(TaskId, Name_Dispatching_Domain, Check_Parents => False)
then
Append_To (Cdecls,
Make_Component_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uDispatching_Domain),
Component_Definition =>
Make_Component_Definition (Loc,
Aliased_Present => False,
Subtype_Indication =>
New_Occurrence_Of
(RTE (RE_Dispatching_Domain_Access), Loc))));
end if;
Insert_After (Size_Decl, Rec_Decl);
-- Analyze the record declaration immediately after construction,
-- because the initialization procedure is needed for single task
-- declarations before the next entity is analyzed.
Analyze (Rec_Decl);
-- Create the declaration of the task body procedure
Proc_Spec := Build_Task_Proc_Specification (Tasktyp);
Body_Decl :=
Make_Subprogram_Declaration (Loc,
Specification => Proc_Spec);
Set_Is_Task_Body_Procedure (Body_Decl);
Insert_After (Rec_Decl, Body_Decl);
-- The subprogram does not comes from source, so we have to indicate the
-- need for debugging information explicitly.
if Comes_From_Source (Original_Node (N)) then
Set_Debug_Info_Needed (Defining_Entity (Proc_Spec));
end if;
-- Ada 2005 (AI-345): Construct the primitive entry wrapper specs before
-- the corresponding record has been frozen.
if Ada_Version >= Ada_2005 then
Build_Wrapper_Specs (Loc, Tasktyp, Rec_Decl);
end if;
-- Ada 2005 (AI-345): We must defer freezing to allow further
-- declaration of primitive subprograms covering task interfaces
if Ada_Version <= Ada_95 then
-- Now we can freeze the corresponding record. This needs manually
-- freezing, since it is really part of the task type, and the task
-- type is frozen at this stage. We of course need the initialization
-- procedure for this corresponding record type and we won't get it
-- in time if we don't freeze now.
declare
L : constant List_Id := Freeze_Entity (Rec_Ent, N);
begin
if Is_Non_Empty_List (L) then
Insert_List_After (Body_Decl, L);
end if;
end;
end if;
-- Complete the expansion of access types to the current task type, if
-- any were declared.
Expand_Previous_Access_Type (Tasktyp);
-- Create wrappers for entries that have contract cases, preconditions
-- and postconditions.
declare
Ent : Entity_Id;
begin
Ent := First_Entity (Tasktyp);
while Present (Ent) loop
if Ekind (Ent) in E_Entry | E_Entry_Family then
Build_Contract_Wrapper (Ent, N);
end if;
Next_Entity (Ent);
end loop;
end;
end Expand_N_Task_Type_Declaration;
-------------------------------
-- Expand_N_Timed_Entry_Call --
-------------------------------
-- A timed entry call in normal case is not implemented using ATC mechanism
-- anymore for efficiency reason.
-- select
-- T.E;
-- S1;
-- or
-- delay D;
-- S2;
-- end select;
-- is expanded as follows:
-- 1) When T.E is a task entry_call;
-- declare
-- B : Boolean;
-- X : Task_Entry_Index := <entry index>;
-- DX : Duration := To_Duration (D);
-- M : Delay_Mode := <discriminant>;
-- P : parms := (parm, parm, parm);
-- begin
-- Timed_Protected_Entry_Call
-- (<acceptor-task>, X, P'Address, DX, M, B);
-- if B then
-- S1;
-- else
-- S2;
-- end if;
-- end;
-- 2) When T.E is a protected entry_call;
-- declare
-- B : Boolean;
-- X : Protected_Entry_Index := <entry index>;
-- DX : Duration := To_Duration (D);
-- M : Delay_Mode := <discriminant>;
-- P : parms := (parm, parm, parm);
-- begin
-- Timed_Protected_Entry_Call
-- (<object>'unchecked_access, X, P'Address, DX, M, B);
-- if B then
-- S1;
-- else
-- S2;
-- end if;
-- end;
-- 3) Ada 2005 (AI-345): When T.E is a dispatching procedure call, there
-- is no delay and the triggering statements are executed. We first
-- determine the kind of the triggering call and then execute a
-- synchronized operation or a direct call.
-- declare
-- B : Boolean := False;
-- C : Ada.Tags.Prim_Op_Kind;
-- DX : Duration := To_Duration (D)
-- K : Ada.Tags.Tagged_Kind :=
-- Ada.Tags.Get_Tagged_Kind (Ada.Tags.Tag (<object>));
-- M : Integer :=...;
-- P : Parameters := (Param1 .. ParamN);
-- S : Integer;
-- begin
-- if K = Ada.Tags.TK_Limited_Tagged
-- or else K = Ada.Tags.TK_Tagged
-- then
-- <dispatching-call>;
-- B := True;
-- else
-- S :=
-- Ada.Tags.Get_Offset_Index
-- (Ada.Tags.Tag (<object>), DT_Position (<dispatching-call>));
-- _Disp_Timed_Select (<object>, S, P'Address, DX, M, C, B);
-- if C = POK_Protected_Entry
-- or else C = POK_Task_Entry
-- then
-- Param1 := P.Param1;
-- ...
-- ParamN := P.ParamN;
-- end if;
-- if B then
-- if C = POK_Procedure
-- or else C = POK_Protected_Procedure
-- or else C = POK_Task_Procedure
-- then
-- <dispatching-call>;
-- end if;
-- end if;
-- end if;
-- if B then
-- <triggering-statements>
-- else
-- <timed-statements>
-- end if;
-- end;
-- The triggering statement and the sequence of timed statements have not
-- been analyzed yet (see Analyzed_Timed_Entry_Call), but they may contain
-- global references if within an instantiation.
procedure Expand_N_Timed_Entry_Call (N : Node_Id) is
Actuals : List_Id;
Blk_Typ : Entity_Id;
Call : Node_Id;
Call_Ent : Entity_Id;
Conc_Typ_Stmts : List_Id;
Concval : Node_Id := Empty; -- init to avoid warning
D_Alt : constant Node_Id := Delay_Alternative (N);
D_Conv : Node_Id;
D_Disc : Node_Id;
D_Stat : Node_Id := Delay_Statement (D_Alt);
D_Stats : List_Id;
D_Type : Entity_Id;
Decls : List_Id;
Dummy : Node_Id;
E_Alt : constant Node_Id := Entry_Call_Alternative (N);
E_Call : Node_Id := Entry_Call_Statement (E_Alt);
E_Stats : List_Id;
Ename : Node_Id;
Formals : List_Id;
Index : Node_Id;
Is_Disp_Select : Boolean;
Lim_Typ_Stmts : List_Id;
Loc : constant Source_Ptr := Sloc (D_Stat);
N_Stats : List_Id;
Obj : Entity_Id;
Param : Node_Id;
Params : List_Id;
Stmt : Node_Id;
Stmts : List_Id;
Unpack : List_Id;
B : Entity_Id; -- Call status flag
C : Entity_Id; -- Call kind
D : Entity_Id; -- Delay
K : Entity_Id; -- Tagged kind
M : Entity_Id; -- Delay mode
P : Entity_Id; -- Parameter block
S : Entity_Id; -- Primitive operation slot
-- Start of processing for Expand_N_Timed_Entry_Call
begin
-- Under the Ravenscar profile, timed entry calls are excluded. An error
-- was already reported on spec, so do not attempt to expand the call.
if Restriction_Active (No_Select_Statements) then
return;
end if;
Process_Statements_For_Controlled_Objects (E_Alt);
Process_Statements_For_Controlled_Objects (D_Alt);
Ensure_Statement_Present (Sloc (D_Stat), D_Alt);
-- Retrieve E_Stats and D_Stats now because the finalization machinery
-- may wrap them in blocks.
E_Stats := Statements (E_Alt);
D_Stats := Statements (D_Alt);
-- The arguments in the call may require dynamic allocation, and the
-- call statement may have been transformed into a block. The block
-- may contain additional declarations for internal entities, and the
-- original call is found by sequential search.
if Nkind (E_Call) = N_Block_Statement then
E_Call := First (Statements (Handled_Statement_Sequence (E_Call)));
while Nkind (E_Call) not in
N_Procedure_Call_Statement | N_Entry_Call_Statement
loop
Next (E_Call);
end loop;
end if;
Is_Disp_Select :=
Ada_Version >= Ada_2005
and then Nkind (E_Call) = N_Procedure_Call_Statement;
if Is_Disp_Select then
Extract_Dispatching_Call (E_Call, Call_Ent, Obj, Actuals, Formals);
Decls := New_List;
Stmts := New_List;
-- Generate:
-- B : Boolean := False;
B := Build_B (Loc, Decls);
-- Generate:
-- C : Ada.Tags.Prim_Op_Kind;
C := Build_C (Loc, Decls);
-- Because the analysis of all statements was disabled, manually
-- analyze the delay statement.
Analyze (D_Stat);
D_Stat := Original_Node (D_Stat);
else
-- Build an entry call using Simple_Entry_Call
Extract_Entry (E_Call, Concval, Ename, Index);
Build_Simple_Entry_Call (E_Call, Concval, Ename, Index);
Decls := Declarations (E_Call);
Stmts := Statements (Handled_Statement_Sequence (E_Call));
if No (Decls) then
Decls := New_List;
end if;
-- Generate:
-- B : Boolean;
B := Make_Defining_Identifier (Loc, Name_uB);
Prepend_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => B,
Object_Definition =>
New_Occurrence_Of (Standard_Boolean, Loc)));
end if;
-- Duration and mode processing
D_Type := Base_Type (Etype (Expression (D_Stat)));
-- Use the type of the delay expression (Calendar or Real_Time) to
-- generate the appropriate conversion.
if Nkind (D_Stat) = N_Delay_Relative_Statement then
D_Disc := Make_Integer_Literal (Loc, 0);
D_Conv := Relocate_Node (Expression (D_Stat));
elsif Is_RTE (D_Type, RO_CA_Time) then
D_Disc := Make_Integer_Literal (Loc, 1);
D_Conv :=
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RO_CA_To_Duration), Loc),
Parameter_Associations =>
New_List (New_Copy (Expression (D_Stat))));
else pragma Assert (Is_RTE (D_Type, RO_RT_Time));
D_Disc := Make_Integer_Literal (Loc, 2);
D_Conv :=
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RO_RT_To_Duration), Loc),
Parameter_Associations =>
New_List (New_Copy (Expression (D_Stat))));
end if;
D := Make_Temporary (Loc, 'D');
-- Generate:
-- D : Duration;
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => D,
Object_Definition => New_Occurrence_Of (Standard_Duration, Loc)));
M := Make_Temporary (Loc, 'M');
-- Generate:
-- M : Integer := (0 | 1 | 2);
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => M,
Object_Definition => New_Occurrence_Of (Standard_Integer, Loc),
Expression => D_Disc));
-- Parameter block processing
-- Manually create the parameter block for dispatching calls. In the
-- case of entries, the block has already been created during the call
-- to Build_Simple_Entry_Call.
if Is_Disp_Select then
-- Compute the delay at this stage because the evaluation of its
-- expression must not occur earlier (see ACVC C97302A).
Append_To (Stmts,
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (D, Loc),
Expression => D_Conv));
-- Tagged kind processing, generate:
-- K : Ada.Tags.Tagged_Kind :=
-- Ada.Tags.Get_Tagged_Kind (Ada.Tags.Tag <object>));
K := Build_K (Loc, Decls, Obj);
Blk_Typ := Build_Parameter_Block (Loc, Actuals, Formals, Decls);
P :=
Parameter_Block_Pack (Loc, Blk_Typ, Actuals, Formals, Decls, Stmts);
-- Dispatch table slot processing, generate:
-- S : Integer;
S := Build_S (Loc, Decls);
-- Generate:
-- S := Ada.Tags.Get_Offset_Index
-- (Ada.Tags.Tag (<object>), DT_Position (Call_Ent));
Conc_Typ_Stmts :=
New_List (Build_S_Assignment (Loc, S, Obj, Call_Ent));
-- Generate:
-- _Disp_Timed_Select (<object>, S, P'Address, D, M, C, B);
-- where Obj is the controlling formal parameter, S is the dispatch
-- table slot number of the dispatching operation, P is the wrapped
-- parameter block, D is the duration, M is the duration mode, C is
-- the call kind and B is the call status.
Params := New_List;
Append_To (Params, New_Copy_Tree (Obj));
Append_To (Params, New_Occurrence_Of (S, Loc));
Append_To (Params,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (P, Loc),
Attribute_Name => Name_Address));
Append_To (Params, New_Occurrence_Of (D, Loc));
Append_To (Params, New_Occurrence_Of (M, Loc));
Append_To (Params, New_Occurrence_Of (C, Loc));
Append_To (Params, New_Occurrence_Of (B, Loc));
Append_To (Conc_Typ_Stmts,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of
(Find_Prim_Op
(Etype (Etype (Obj)), Name_uDisp_Timed_Select), Loc),
Parameter_Associations => Params));
-- Generate:
-- if C = POK_Protected_Entry
-- or else C = POK_Task_Entry
-- then
-- Param1 := P.Param1;
-- ...
-- ParamN := P.ParamN;
-- end if;
Unpack := Parameter_Block_Unpack (Loc, P, Actuals, Formals);
-- Generate the if statement only when the packed parameters need
-- explicit assignments to their corresponding actuals.
if Present (Unpack) then
Append_To (Conc_Typ_Stmts,
Make_Implicit_If_Statement (N,
Condition =>
Make_Or_Else (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd => New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of
(RTE (RE_POK_Protected_Entry), Loc)),
Right_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd => New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_POK_Task_Entry), Loc))),
Then_Statements => Unpack));
end if;
-- Generate:
-- if B then
-- if C = POK_Procedure
-- or else C = POK_Protected_Procedure
-- or else C = POK_Task_Procedure
-- then
-- <dispatching-call>
-- end if;
-- end if;
N_Stats := New_List (
Make_Implicit_If_Statement (N,
Condition =>
Make_Or_Else (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd => New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (RE_POK_Procedure), Loc)),
Right_Opnd =>
Make_Or_Else (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd => New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of (RTE (
RE_POK_Protected_Procedure), Loc)),
Right_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd => New_Occurrence_Of (C, Loc),
Right_Opnd =>
New_Occurrence_Of
(RTE (RE_POK_Task_Procedure), Loc)))),
Then_Statements => New_List (E_Call)));
Append_To (Conc_Typ_Stmts,
Make_Implicit_If_Statement (N,
Condition => New_Occurrence_Of (B, Loc),
Then_Statements => N_Stats));
-- Generate:
-- <dispatching-call>;
-- B := True;
Lim_Typ_Stmts :=
New_List (New_Copy_Tree (E_Call),
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (B, Loc),
Expression => New_Occurrence_Of (Standard_True, Loc)));
-- Generate:
-- if K = Ada.Tags.TK_Limited_Tagged
-- or else K = Ada.Tags.TK_Tagged
-- then
-- Lim_Typ_Stmts
-- else
-- Conc_Typ_Stmts
-- end if;
Append_To (Stmts,
Make_Implicit_If_Statement (N,
Condition => Build_Dispatching_Tag_Check (K, N),
Then_Statements => Lim_Typ_Stmts,
Else_Statements => Conc_Typ_Stmts));
-- Generate:
-- if B then
-- <triggering-statements>
-- else
-- <timed-statements>
-- end if;
Append_To (Stmts,
Make_Implicit_If_Statement (N,
Condition => New_Occurrence_Of (B, Loc),
Then_Statements => E_Stats,
Else_Statements => D_Stats));
else
-- Simple case of a nondispatching trigger. Skip assignments to
-- temporaries created for in-out parameters.
-- This makes unwarranted assumptions about the shape of the expanded
-- tree for the call, and should be cleaned up ???
Stmt := First (Stmts);
while Nkind (Stmt) /= N_Procedure_Call_Statement loop
Next (Stmt);
end loop;
-- Compute the delay at this stage because the evaluation of
-- its expression must not occur earlier (see ACVC C97302A).
Insert_Before (Stmt,
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (D, Loc),
Expression => D_Conv));
Call := Stmt;
Params := Parameter_Associations (Call);
-- For a protected type, we build a Timed_Protected_Entry_Call
if Is_Protected_Type (Etype (Concval)) then
-- Create a new call statement
Param := First (Params);
while Present (Param)
and then not Is_RTE (Etype (Param), RE_Call_Modes)
loop
Next (Param);
end loop;
Dummy := Remove_Next (Next (Param));
-- Remove garbage is following the Cancel_Param if present
Dummy := Next (Param);
-- Remove the mode of the Protected_Entry_Call call, then remove
-- the Communication_Block of the Protected_Entry_Call call, and
-- finally add Duration and a Delay_Mode parameter
pragma Assert (Present (Param));
Rewrite (Param, New_Occurrence_Of (D, Loc));
Rewrite (Dummy, New_Occurrence_Of (M, Loc));
-- Add a Boolean flag for successful entry call
Append_To (Params, New_Occurrence_Of (B, Loc));
case Corresponding_Runtime_Package (Etype (Concval)) is
when System_Tasking_Protected_Objects_Entries =>
Rewrite (Call,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of
(RTE (RE_Timed_Protected_Entry_Call), Loc),
Parameter_Associations => Params));
when others =>
raise Program_Error;
end case;
-- For the task case, build a Timed_Task_Entry_Call
else
-- Create a new call statement
Append_To (Params, New_Occurrence_Of (D, Loc));
Append_To (Params, New_Occurrence_Of (M, Loc));
Append_To (Params, New_Occurrence_Of (B, Loc));
Rewrite (Call,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Timed_Task_Entry_Call), Loc),
Parameter_Associations => Params));
end if;
Append_To (Stmts,
Make_Implicit_If_Statement (N,
Condition => New_Occurrence_Of (B, Loc),
Then_Statements => E_Stats,
Else_Statements => D_Stats));
end if;
Rewrite (N,
Make_Block_Statement (Loc,
Declarations => Decls,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc, Stmts)));
Analyze (N);
-- Some items in Decls used to be in the N_Block in E_Call that is
-- constructed in Expand_Entry_Call, and are now in the new Block
-- into which N has been rewritten. Adjust their scopes to reflect that.
if Nkind (E_Call) = N_Block_Statement then
Obj := First_Entity (Entity (Identifier (E_Call)));
while Present (Obj) loop
Set_Scope (Obj, Entity (Identifier (N)));
Next_Entity (Obj);
end loop;
end if;
Reset_Scopes_To (N, Entity (Identifier (N)));
end Expand_N_Timed_Entry_Call;
----------------------------------------
-- Expand_Protected_Body_Declarations --
----------------------------------------
procedure Expand_Protected_Body_Declarations
(N : Node_Id;
Spec_Id : Entity_Id)
is
begin
if No_Run_Time_Mode then
Error_Msg_CRT ("protected body", N);
return;
elsif Expander_Active then
-- Associate discriminals with the first subprogram or entry body to
-- be expanded.
if Present (First_Protected_Operation (Declarations (N))) then
Set_Discriminals (Parent (Spec_Id));
end if;
end if;
end Expand_Protected_Body_Declarations;
-------------------------
-- External_Subprogram --
-------------------------
function External_Subprogram (E : Entity_Id) return Entity_Id is
Subp : constant Entity_Id := Protected_Body_Subprogram (E);
begin
-- The internal and external subprograms follow each other on the entity
-- chain. Note that previously private operations had no separate
-- external subprogram. We now create one in all cases, because a
-- private operation may actually appear in an external call, through
-- a 'Access reference used for a callback.
-- If the operation is a function that returns an anonymous access type,
-- the corresponding itype appears before the operation, and must be
-- skipped.
-- This mechanism is fragile, there should be a real link between the
-- two versions of the operation, but there is no place to put it ???
if Is_Access_Type (Next_Entity (Subp)) then
return Next_Entity (Next_Entity (Subp));
else
return Next_Entity (Subp);
end if;
end External_Subprogram;
------------------------------
-- Extract_Dispatching_Call --
------------------------------
procedure Extract_Dispatching_Call
(N : Node_Id;
Call_Ent : out Entity_Id;
Object : out Entity_Id;
Actuals : out List_Id;
Formals : out List_Id)
is
Call_Nam : Node_Id;
begin
pragma Assert (Nkind (N) = N_Procedure_Call_Statement);
if Present (Original_Node (N)) then
Call_Nam := Name (Original_Node (N));
else
Call_Nam := Name (N);
end if;
-- Retrieve the name of the dispatching procedure. It contains the
-- dispatch table slot number.
loop
case Nkind (Call_Nam) is
when N_Identifier =>
exit;
when N_Selected_Component =>
Call_Nam := Selector_Name (Call_Nam);
when others =>
raise Program_Error;
end case;
end loop;
Actuals := Parameter_Associations (N);
Call_Ent := Entity (Call_Nam);
Formals := Parameter_Specifications (Parent (Call_Ent));
Object := First (Actuals);
if Present (Original_Node (Object)) then
Object := Original_Node (Object);
end if;
-- If the type of the dispatching object is an access type then return
-- an explicit dereference of a copy of the object, and note that this
-- is the controlling actual of the call.
if Is_Access_Type (Etype (Object)) then
Object :=
Make_Explicit_Dereference (Sloc (N), New_Copy_Tree (Object));
Analyze (Object);
Set_Is_Controlling_Actual (Object);
end if;
end Extract_Dispatching_Call;
-------------------
-- Extract_Entry --
-------------------
procedure Extract_Entry
(N : Node_Id;
Concval : out Node_Id;
Ename : out Node_Id;
Index : out Node_Id)
is
Nam : constant Node_Id := Name (N);
begin
-- For a simple entry, the name is a selected component, with the
-- prefix being the task value, and the selector being the entry.
if Nkind (Nam) = N_Selected_Component then
Concval := Prefix (Nam);
Ename := Selector_Name (Nam);
Index := Empty;
-- For a member of an entry family, the name is an indexed component
-- where the prefix is a selected component, whose prefix in turn is
-- the task value, and whose selector is the entry family. The single
-- expression in the expressions list of the indexed component is the
-- subscript for the family.
else pragma Assert (Nkind (Nam) = N_Indexed_Component);
Concval := Prefix (Prefix (Nam));
Ename := Selector_Name (Prefix (Nam));
Index := First (Expressions (Nam));
end if;
-- Through indirection, the type may actually be a limited view of a
-- concurrent type. When compiling a call, the non-limited view of the
-- type is visible.
if From_Limited_With (Etype (Concval)) then
Set_Etype (Concval, Non_Limited_View (Etype (Concval)));
end if;
end Extract_Entry;
-------------------
-- Family_Offset --
-------------------
function Family_Offset
(Loc : Source_Ptr;
Hi : Node_Id;
Lo : Node_Id;
Ttyp : Entity_Id;
Cap : Boolean) return Node_Id
is
Ityp : Entity_Id;
Real_Hi : Node_Id;
Real_Lo : Node_Id;
function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id;
-- If one of the bounds is a reference to a discriminant, replace with
-- corresponding discriminal of type. Within the body of a task retrieve
-- the renamed discriminant by simple visibility, using its generated
-- name. Within a protected object, find the original discriminant and
-- replace it with the discriminal of the current protected operation.
------------------------------
-- Convert_Discriminant_Ref --
------------------------------
function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id is
Loc : constant Source_Ptr := Sloc (Bound);
B : Node_Id;
D : Entity_Id;
begin
if Is_Entity_Name (Bound)
and then Ekind (Entity (Bound)) = E_Discriminant
then
if Is_Task_Type (Ttyp) and then Has_Completion (Ttyp) then
B := Make_Identifier (Loc, Chars (Entity (Bound)));
Find_Direct_Name (B);
elsif Is_Protected_Type (Ttyp) then
D := First_Discriminant (Ttyp);
while Chars (D) /= Chars (Entity (Bound)) loop
Next_Discriminant (D);
end loop;
B := New_Occurrence_Of (Discriminal (D), Loc);
else
B := New_Occurrence_Of (Discriminal (Entity (Bound)), Loc);
end if;
elsif Nkind (Bound) = N_Attribute_Reference then
return Bound;
else
B := New_Copy_Tree (Bound);
end if;
return
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Pos,
Prefix => New_Occurrence_Of (Etype (Bound), Loc),
Expressions => New_List (B));
end Convert_Discriminant_Ref;
-- Start of processing for Family_Offset
begin
Real_Hi := Convert_Discriminant_Ref (Hi);
Real_Lo := Convert_Discriminant_Ref (Lo);
if Cap then
if Is_Task_Type (Ttyp) then
Ityp := RTE (RE_Task_Entry_Index);
else
Ityp := RTE (RE_Protected_Entry_Index);
end if;
Real_Hi :=
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ityp, Loc),
Attribute_Name => Name_Min,
Expressions => New_List (
Real_Hi,
Make_Integer_Literal (Loc, Entry_Family_Bound - 1)));
Real_Lo :=
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ityp, Loc),
Attribute_Name => Name_Max,
Expressions => New_List (
Real_Lo,
Make_Integer_Literal (Loc, -Entry_Family_Bound)));
end if;
return Make_Op_Subtract (Loc, Real_Hi, Real_Lo);
end Family_Offset;
-----------------
-- Family_Size --
-----------------
function Family_Size
(Loc : Source_Ptr;
Hi : Node_Id;
Lo : Node_Id;
Ttyp : Entity_Id;
Cap : Boolean) return Node_Id
is
Ityp : Entity_Id;
begin
if Is_Task_Type (Ttyp) then
Ityp := RTE (RE_Task_Entry_Index);
else
Ityp := RTE (RE_Protected_Entry_Index);
end if;
return
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ityp, Loc),
Attribute_Name => Name_Max,
Expressions => New_List (
Make_Op_Add (Loc,
Left_Opnd => Family_Offset (Loc, Hi, Lo, Ttyp, Cap),
Right_Opnd => Make_Integer_Literal (Loc, 1)),
Make_Integer_Literal (Loc, 0)));
end Family_Size;
----------------------------
-- Find_Enclosing_Context --
----------------------------
procedure Find_Enclosing_Context
(N : Node_Id;
Context : out Node_Id;
Context_Id : out Entity_Id;
Context_Decls : out List_Id)
is
begin
-- Traverse the parent chain looking for an enclosing body, block,
-- package or return statement.
Context := Parent (N);
while Present (Context) loop
if Nkind (Context) in N_Entry_Body
| N_Extended_Return_Statement
| N_Package_Body
| N_Package_Declaration
| N_Subprogram_Body
| N_Task_Body
then
exit;
-- Do not consider block created to protect a list of statements with
-- an Abort_Defer / Abort_Undefer_Direct pair.
elsif Nkind (Context) = N_Block_Statement
and then not Is_Abort_Block (Context)
then
exit;
end if;
Context := Parent (Context);
end loop;
pragma Assert (Present (Context));
-- Extract the constituents of the context
if Nkind (Context) = N_Extended_Return_Statement then
Context_Decls := Return_Object_Declarations (Context);
Context_Id := Return_Statement_Entity (Context);
-- Package declarations and bodies use a common library-level activation
-- chain or task master, therefore return the package declaration as the
-- proper carrier for the appropriate flag.
elsif Nkind (Context) = N_Package_Body then
Context_Decls := Declarations (Context);
Context_Id := Corresponding_Spec (Context);
Context := Parent (Context_Id);
if Nkind (Context) = N_Defining_Program_Unit_Name then
Context := Parent (Parent (Context));
else
Context := Parent (Context);
end if;
elsif Nkind (Context) = N_Package_Declaration then
Context_Decls := Visible_Declarations (Specification (Context));
Context_Id := Defining_Unit_Name (Specification (Context));
if Nkind (Context_Id) = N_Defining_Program_Unit_Name then
Context_Id := Defining_Identifier (Context_Id);
end if;
else
if Nkind (Context) = N_Block_Statement then
Context_Id := Entity (Identifier (Context));
if No (Declarations (Context)) then
Set_Declarations (Context, New_List);
end if;
elsif Nkind (Context) = N_Entry_Body then
Context_Id := Defining_Identifier (Context);
elsif Nkind (Context) = N_Subprogram_Body then
if Present (Corresponding_Spec (Context)) then
Context_Id := Corresponding_Spec (Context);
else
Context_Id := Defining_Unit_Name (Specification (Context));
if Nkind (Context_Id) = N_Defining_Program_Unit_Name then
Context_Id := Defining_Identifier (Context_Id);
end if;
end if;
elsif Nkind (Context) = N_Task_Body then
Context_Id := Corresponding_Spec (Context);
else
raise Program_Error;
end if;
Context_Decls := Declarations (Context);
end if;
pragma Assert (Present (Context_Id));
pragma Assert (Present (Context_Decls));
end Find_Enclosing_Context;
-----------------------
-- Find_Master_Scope --
-----------------------
function Find_Master_Scope (E : Entity_Id) return Entity_Id is
S : Entity_Id;
begin
-- In Ada 2005, the master is the innermost enclosing scope that is not
-- transient. If the enclosing block is the rewriting of a call or the
-- scope is an extended return statement this is valid master. The
-- master in an extended return is only used within the return, and is
-- subsequently overwritten in Move_Activation_Chain, but it must exist
-- now before that overwriting occurs.
S := Scope (E);
if Ada_Version >= Ada_2005 then
while Is_Internal (S) loop
if Nkind (Parent (S)) = N_Block_Statement
and then Has_Master_Entity (S)
then
exit;
elsif Ekind (S) = E_Return_Statement then
exit;
else
S := Scope (S);
end if;
end loop;
end if;
return S;
end Find_Master_Scope;
-------------------------------
-- First_Protected_Operation --
-------------------------------
function First_Protected_Operation (D : List_Id) return Node_Id is
First_Op : Node_Id;
begin
First_Op := First (D);
while Present (First_Op)
and then Nkind (First_Op) not in N_Subprogram_Body | N_Entry_Body
loop
Next (First_Op);
end loop;
return First_Op;
end First_Protected_Operation;
---------------------------------------
-- Install_Private_Data_Declarations --
---------------------------------------
procedure Install_Private_Data_Declarations
(Loc : Source_Ptr;
Spec_Id : Entity_Id;
Conc_Typ : Entity_Id;
Body_Nod : Node_Id;
Decls : List_Id;
Barrier : Boolean := False;
Family : Boolean := False)
is
Is_Protected : constant Boolean := Is_Protected_Type (Conc_Typ);
Decl : Node_Id;
Def : Node_Id;
Insert_Node : Node_Id := Empty;
Obj_Ent : Entity_Id;
procedure Add (Decl : Node_Id);
-- Add a single declaration after Insert_Node. If this is the first
-- addition, Decl is added to the front of Decls and it becomes the
-- insertion node.
function Replace_Bound (Bound : Node_Id) return Node_Id;
-- The bounds of an entry index may depend on discriminants, create a
-- reference to the corresponding prival. Otherwise return a duplicate
-- of the original bound.
---------
-- Add --
---------
procedure Add (Decl : Node_Id) is
begin
if No (Insert_Node) then
Prepend_To (Decls, Decl);
else
Insert_After (Insert_Node, Decl);
end if;
Insert_Node := Decl;
end Add;
-------------------
-- Replace_Bound --
-------------------
function Replace_Bound (Bound : Node_Id) return Node_Id is
begin
if Nkind (Bound) = N_Identifier
and then Is_Discriminal (Entity (Bound))
then
return Make_Identifier (Loc, Chars (Entity (Bound)));
else
return Duplicate_Subexpr (Bound);
end if;
end Replace_Bound;
-- Start of processing for Install_Private_Data_Declarations
begin
-- Step 1: Retrieve the concurrent object entity. Obj_Ent can denote
-- formal parameter _O, _object or _task depending on the context.
Obj_Ent := Concurrent_Object (Spec_Id, Conc_Typ);
-- Special processing of _O for barrier functions, protected entries
-- and families.
if Barrier
or else
(Is_Protected
and then
(Ekind (Spec_Id) = E_Entry
or else Ekind (Spec_Id) = E_Entry_Family))
then
declare
Conc_Rec : constant Entity_Id :=
Corresponding_Record_Type (Conc_Typ);
Typ_Id : constant Entity_Id :=
Make_Defining_Identifier (Loc,
New_External_Name (Chars (Conc_Rec), 'P'));
begin
-- Generate:
-- type prot_typVP is access prot_typV;
Decl :=
Make_Full_Type_Declaration (Loc,
Defining_Identifier => Typ_Id,
Type_Definition =>
Make_Access_To_Object_Definition (Loc,
Subtype_Indication =>
New_Occurrence_Of (Conc_Rec, Loc)));
Add (Decl);
-- Generate:
-- _object : prot_typVP := prot_typV (_O);
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier =>
Make_Defining_Identifier (Loc, Name_uObject),
Object_Definition => New_Occurrence_Of (Typ_Id, Loc),
Expression =>
Unchecked_Convert_To (Typ_Id,
New_Occurrence_Of (Obj_Ent, Loc)));
Add (Decl);
-- Set the reference to the concurrent object
Obj_Ent := Defining_Identifier (Decl);
end;
end if;
-- Step 2: Create the Protection object and build its declaration for
-- any protected entry (family) of subprogram. Note for the lock-free
-- implementation, the Protection object is not needed anymore.
if Is_Protected and then not Uses_Lock_Free (Conc_Typ) then
declare
Prot_Ent : constant Entity_Id := Make_Temporary (Loc, 'R');
Prot_Typ : RE_Id;
begin
Set_Protection_Object (Spec_Id, Prot_Ent);
-- Determine the proper protection type
if Has_Attach_Handler (Conc_Typ)
and then not Restricted_Profile
then
Prot_Typ := RE_Static_Interrupt_Protection;
elsif Has_Interrupt_Handler (Conc_Typ)
and then not Restriction_Active (No_Dynamic_Attachment)
then
Prot_Typ := RE_Dynamic_Interrupt_Protection;
else
case Corresponding_Runtime_Package (Conc_Typ) is
when System_Tasking_Protected_Objects_Entries =>
Prot_Typ := RE_Protection_Entries;
when System_Tasking_Protected_Objects_Single_Entry =>
Prot_Typ := RE_Protection_Entry;
when System_Tasking_Protected_Objects =>
Prot_Typ := RE_Protection;
when others =>
raise Program_Error;
end case;
end if;
-- Generate:
-- conc_typR : protection_typ renames _object._object;
Decl :=
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier => Prot_Ent,
Subtype_Mark =>
New_Occurrence_Of (RTE (Prot_Typ), Loc),
Name =>
Make_Selected_Component (Loc,
Prefix => New_Occurrence_Of (Obj_Ent, Loc),
Selector_Name => Make_Identifier (Loc, Name_uObject)));
Add (Decl);
end;
end if;
-- Step 3: Add discriminant renamings (if any)
if Has_Discriminants (Conc_Typ) then
declare
D : Entity_Id;
begin
D := First_Discriminant (Conc_Typ);
while Present (D) loop
-- Adjust the source location
Set_Sloc (Discriminal (D), Loc);
-- Generate:
-- discr_name : discr_typ renames _object.discr_name;
-- or
-- discr_name : discr_typ renames _task.discr_name;
Decl :=
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier => Discriminal (D),
Subtype_Mark => New_Occurrence_Of (Etype (D), Loc),
Name =>
Make_Selected_Component (Loc,
Prefix => New_Occurrence_Of (Obj_Ent, Loc),
Selector_Name => Make_Identifier (Loc, Chars (D))));
Add (Decl);
-- Set debug info needed on this renaming declaration even
-- though it does not come from source, so that the debugger
-- will get the right information for these generated names.
Set_Debug_Info_Needed (Discriminal (D));
Next_Discriminant (D);
end loop;
end;
end if;
-- Step 4: Add private component renamings (if any)
if Is_Protected then
Def := Protected_Definition (Parent (Conc_Typ));
if Present (Private_Declarations (Def)) then
declare
Comp : Node_Id;
Comp_Id : Entity_Id;
Decl_Id : Entity_Id;
Nam : Name_Id;
begin
Comp := First (Private_Declarations (Def));
while Present (Comp) loop
if Nkind (Comp) = N_Component_Declaration then
Comp_Id := Defining_Identifier (Comp);
Nam := Chars (Comp_Id);
Decl_Id := Make_Defining_Identifier (Sloc (Comp_Id), Nam);
-- Minimal decoration
if Ekind (Spec_Id) = E_Function then
Mutate_Ekind (Decl_Id, E_Constant);
else
Mutate_Ekind (Decl_Id, E_Variable);
end if;
Set_Prival (Comp_Id, Decl_Id);
Set_Prival_Link (Decl_Id, Comp_Id);
Set_Is_Aliased (Decl_Id, Is_Aliased (Comp_Id));
Set_Is_Independent (Decl_Id, Is_Independent (Comp_Id));
-- Copy the Comes_From_Source flag of the component, as
-- the renaming may be the only entity directly seen by
-- the user in the context, but do not warn for it.
Set_Comes_From_Source
(Decl_Id, Comes_From_Source (Comp_Id));
Set_Warnings_Off (Decl_Id);
-- Generate:
-- comp_name : comp_typ renames _object.comp_name;
Decl :=
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier => Decl_Id,
Subtype_Mark =>
New_Occurrence_Of (Etype (Comp_Id), Loc),
Name =>
Make_Selected_Component (Loc,
Prefix => New_Occurrence_Of (Obj_Ent, Loc),
Selector_Name => Make_Identifier (Loc, Nam)));
Add (Decl);
end if;
Next (Comp);
end loop;
end;
end if;
end if;
-- Step 5: Add the declaration of the entry index and the associated
-- type for barrier functions and entry families.
if (Barrier and Family) or else Ekind (Spec_Id) = E_Entry_Family then
declare
E : constant Entity_Id := Index_Object (Spec_Id);
Index : constant Entity_Id :=
Defining_Identifier
(Entry_Index_Specification
(Entry_Body_Formal_Part (Body_Nod)));
Index_Con : constant Entity_Id :=
Make_Defining_Identifier (Loc, Chars (Index));
High : Node_Id;
Index_Typ : Entity_Id;
Low : Node_Id;
begin
-- Minimal decoration
Mutate_Ekind (Index_Con, E_Constant);
Set_Entry_Index_Constant (Index, Index_Con);
Set_Discriminal_Link (Index_Con, Index);
-- Retrieve the bounds of the entry family
High := Type_High_Bound (Etype (Index));
Low := Type_Low_Bound (Etype (Index));
-- In the simple case the entry family is given by a subtype mark
-- and the index constant has the same type.
if Is_Entity_Name (Original_Node (
Discrete_Subtype_Definition (Parent (Index))))
then
Index_Typ := Etype (Index);
-- Otherwise a new subtype declaration is required
else
High := Replace_Bound (High);
Low := Replace_Bound (Low);
Index_Typ := Make_Temporary (Loc, 'J');
-- Generate:
-- subtype Jnn is <Etype of Index> range Low .. High;
Decl :=
Make_Subtype_Declaration (Loc,
Defining_Identifier => Index_Typ,
Subtype_Indication =>
Make_Subtype_Indication (Loc,
Subtype_Mark =>
New_Occurrence_Of (Base_Type (Etype (Index)), Loc),
Constraint =>
Make_Range_Constraint (Loc,
Range_Expression =>
Make_Range (Loc, Low, High))));
Add (Decl);
end if;
Set_Etype (Index_Con, Index_Typ);
-- Create the object which designates the index:
-- J : constant Jnn :=
-- Jnn'Val (_E - <index expr> + Jnn'Pos (Jnn'First));
--
-- where Jnn is the subtype created above or the original type of
-- the index, _E is a formal of the protected body subprogram and
-- <index expr> is the index of the first family member.
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Index_Con,
Constant_Present => True,
Object_Definition =>
New_Occurrence_Of (Index_Typ, Loc),
Expression =>
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Index_Typ, Loc),
Attribute_Name => Name_Val,
Expressions => New_List (
Make_Op_Add (Loc,
Left_Opnd =>
Make_Op_Subtract (Loc,
Left_Opnd => New_Occurrence_Of (E, Loc),
Right_Opnd =>
Entry_Index_Expression (Loc,
Defining_Identifier (Body_Nod),
Empty, Conc_Typ)),
Right_Opnd =>
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Index_Typ, Loc),
Attribute_Name => Name_Pos,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Index_Typ, Loc),
Attribute_Name => Name_First)))))));
Add (Decl);
end;
end if;
end Install_Private_Data_Declarations;
---------------------------------
-- Is_Potentially_Large_Family --
---------------------------------
function Is_Potentially_Large_Family
(Base_Index : Entity_Id;
Conctyp : Entity_Id;
Lo : Node_Id;
Hi : Node_Id) return Boolean
is
begin
return Scope (Base_Index) = Standard_Standard
and then Base_Index = Base_Type (Standard_Integer)
and then Has_Defaulted_Discriminants (Conctyp)
and then
(Denotes_Discriminant (Lo, True)
or else
Denotes_Discriminant (Hi, True));
end Is_Potentially_Large_Family;
-------------------------------------
-- Is_Private_Primitive_Subprogram --
-------------------------------------
function Is_Private_Primitive_Subprogram (Id : Entity_Id) return Boolean is
begin
return
(Ekind (Id) = E_Function or else Ekind (Id) = E_Procedure)
and then Is_Private_Primitive (Id);
end Is_Private_Primitive_Subprogram;
------------------
-- Index_Object --
------------------
function Index_Object (Spec_Id : Entity_Id) return Entity_Id is
Bod_Subp : constant Entity_Id := Protected_Body_Subprogram (Spec_Id);
Formal : Entity_Id;
begin
Formal := First_Formal (Bod_Subp);
while Present (Formal) loop
-- Look for formal parameter _E
if Chars (Formal) = Name_uE then
return Formal;
end if;
Next_Formal (Formal);
end loop;
-- A protected body subprogram should always have the parameter in
-- question.
raise Program_Error;
end Index_Object;
--------------------------------
-- Make_Initialize_Protection --
--------------------------------
function Make_Initialize_Protection
(Protect_Rec : Entity_Id) return List_Id
is
Loc : constant Source_Ptr := Sloc (Protect_Rec);
P_Arr : Entity_Id;
Pdec : Node_Id;
Ptyp : constant Node_Id :=
Corresponding_Concurrent_Type (Protect_Rec);
Args : List_Id;
L : constant List_Id := New_List;
Has_Entry : constant Boolean := Has_Entries (Ptyp);
Prio_Type : Entity_Id;
Prio_Var : Entity_Id := Empty;
Restricted : constant Boolean := Restricted_Profile;
begin
-- We may need two calls to properly initialize the object, one to
-- Initialize_Protection, and possibly one to Install_Handlers if we
-- have a pragma Attach_Handler.
-- Get protected declaration. In the case of a task type declaration,
-- this is simply the parent of the protected type entity. In the single
-- protected object declaration, this parent will be the implicit type,
-- and we can find the corresponding single protected object declaration
-- by searching forward in the declaration list in the tree.
-- Is the test for N_Single_Protected_Declaration needed here??? Nodes
-- of this type should have been removed during semantic analysis.
Pdec := Parent (Ptyp);
while Nkind (Pdec) not in
N_Protected_Type_Declaration | N_Single_Protected_Declaration
loop
Next (Pdec);
end loop;
-- Build the parameter list for the call. Note that _Init is the name
-- of the formal for the object to be initialized, which is the task
-- value record itself.
Args := New_List;
-- For lock-free implementation, skip initializations of the Protection
-- object.
if not Uses_Lock_Free (Defining_Identifier (Pdec)) then
-- Object parameter. This is a pointer to the object of type
-- Protection used by the GNARL to control the protected object.
Append_To (Args,
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name => Make_Identifier (Loc, Name_uObject)),
Attribute_Name => Name_Unchecked_Access));
-- Priority parameter. Set to Unspecified_Priority unless there is a
-- Priority rep item, in which case we take the value from the pragma
-- or attribute definition clause, or there is an Interrupt_Priority
-- rep item and no Priority rep item, and we set the ceiling to
-- Interrupt_Priority'Last, an implementation-defined value, see
-- (RM D.3(10)).
if Has_Rep_Item (Ptyp, Name_Priority, Check_Parents => False) then
declare
Prio_Clause : constant Node_Id :=
Get_Rep_Item
(Ptyp, Name_Priority, Check_Parents => False);
Prio : Node_Id;
begin
-- Pragma Priority
if Nkind (Prio_Clause) = N_Pragma then
Prio :=
Expression
(First (Pragma_Argument_Associations (Prio_Clause)));
-- Get_Rep_Item returns either priority pragma
if Pragma_Name (Prio_Clause) = Name_Priority then
Prio_Type := RTE (RE_Any_Priority);
else
Prio_Type := RTE (RE_Interrupt_Priority);
end if;
-- Attribute definition clause Priority
else
if Chars (Prio_Clause) = Name_Priority then
Prio_Type := RTE (RE_Any_Priority);
else
Prio_Type := RTE (RE_Interrupt_Priority);
end if;
Prio := Expression (Prio_Clause);
end if;
-- Always create a locale variable to capture the priority.
-- The priority is also passed to Install_Restriced_Handlers.
-- Note that it is really necessary to create this variable
-- explicitly. It might be thought that removing side effects
-- would the appropriate approach, but that could generate
-- declarations improperly placed in the enclosing scope.
Prio_Var := Make_Temporary (Loc, 'R', Prio);
Append_To (L,
Make_Object_Declaration (Loc,
Defining_Identifier => Prio_Var,
Object_Definition => New_Occurrence_Of (Prio_Type, Loc),
Expression => Relocate_Node (Prio)));
Append_To (Args, New_Occurrence_Of (Prio_Var, Loc));
end;
-- When no priority is specified but an xx_Handler pragma is, we
-- default to System.Interrupts.Default_Interrupt_Priority, see
-- D.3(10).
elsif Has_Attach_Handler (Ptyp)
or else Has_Interrupt_Handler (Ptyp)
then
Append_To (Args,
New_Occurrence_Of (RTE (RE_Default_Interrupt_Priority), Loc));
-- Normal case, no priority or xx_Handler specified, default priority
else
Append_To (Args,
New_Occurrence_Of (RTE (RE_Unspecified_Priority), Loc));
end if;
-- Deadline_Floor parameter for GNAT_Ravenscar_EDF runtimes
if Restricted_Profile and Task_Dispatching_Policy = 'E' then
Deadline_Floor : declare
Item : constant Node_Id :=
Get_Rep_Item
(Ptyp, Name_Deadline_Floor, Check_Parents => False);
Deadline : Node_Id;
begin
if Present (Item) then
-- Pragma Deadline_Floor
if Nkind (Item) = N_Pragma then
Deadline :=
Expression
(First (Pragma_Argument_Associations (Item)));
-- Attribute definition clause Deadline_Floor
else
pragma Assert
(Nkind (Item) = N_Attribute_Definition_Clause);
Deadline := Expression (Item);
end if;
Append_To (Args, Deadline);
-- Unusual case: default deadline
else
Append_To (Args,
New_Occurrence_Of (RTE (RE_Time_Span_Zero), Loc));
end if;
end Deadline_Floor;
end if;
-- Test for Compiler_Info parameter. This parameter allows entry body
-- procedures and barrier functions to be called from the runtime. It
-- is a pointer to the record generated by the compiler to represent
-- the protected object.
-- A protected type without entries that covers an interface and
-- overrides the abstract routines with protected procedures is
-- considered equivalent to a protected type with entries in the
-- context of dispatching select statements.
-- Protected types with interrupt handlers (when not using a
-- restricted profile) are also considered equivalent to protected
-- types with entries.
-- The types which are used (Static_Interrupt_Protection and
-- Dynamic_Interrupt_Protection) are derived from Protection_Entries.
declare
Pkg_Id : constant RTU_Id := Corresponding_Runtime_Package (Ptyp);
Called_Subp : RE_Id;
begin
case Pkg_Id is
when System_Tasking_Protected_Objects_Entries =>
Called_Subp := RE_Initialize_Protection_Entries;
-- Argument Compiler_Info
Append_To (Args,
Make_Attribute_Reference (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Attribute_Name => Name_Address));
when System_Tasking_Protected_Objects_Single_Entry =>
Called_Subp := RE_Initialize_Protection_Entry;
-- Argument Compiler_Info
Append_To (Args,
Make_Attribute_Reference (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Attribute_Name => Name_Address));
when System_Tasking_Protected_Objects =>
Called_Subp := RE_Initialize_Protection;
when others =>
raise Program_Error;
end case;
-- Entry_Queue_Maxes parameter. This is an access to an array of
-- naturals representing the entry queue maximums for each entry
-- in the protected type. Zero represents no max. The access is
-- null if there is no limit for all entries (usual case).
if Has_Entry
and then Pkg_Id = System_Tasking_Protected_Objects_Entries
then
if Present (Entry_Max_Queue_Lengths_Array (Ptyp)) then
Append_To (Args,
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of
(Entry_Max_Queue_Lengths_Array (Ptyp), Loc),
Attribute_Name => Name_Unrestricted_Access));
else
Append_To (Args, Make_Null (Loc));
end if;
-- Edge cases exist where entry initialization functions are
-- called, but no entries exist, so null is appended.
elsif Pkg_Id = System_Tasking_Protected_Objects_Entries then
Append_To (Args, Make_Null (Loc));
end if;
-- Entry_Bodies parameter. This is a pointer to an array of
-- pointers to the entry body procedures and barrier functions of
-- the object. If the protected type has no entries this object
-- will not exist, in this case, pass a null (it can happen when
-- there are protected interrupt handlers or interfaces).
if Has_Entry then
P_Arr := Entry_Bodies_Array (Ptyp);
-- Argument Entry_Body (for single entry) or Entry_Bodies (for
-- multiple entries).
Append_To (Args,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (P_Arr, Loc),
Attribute_Name => Name_Unrestricted_Access));
if Pkg_Id = System_Tasking_Protected_Objects_Entries then
-- Find index mapping function (clumsy but ok for now)
while Ekind (P_Arr) /= E_Function loop
Next_Entity (P_Arr);
end loop;
Append_To (Args,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (P_Arr, Loc),
Attribute_Name => Name_Unrestricted_Access));
end if;
elsif Pkg_Id = System_Tasking_Protected_Objects_Single_Entry then
-- This is the case where we have a protected object with
-- interfaces and no entries, and the single entry restriction
-- is in effect. We pass a null pointer for the entry
-- parameter because there is no actual entry.
Append_To (Args, Make_Null (Loc));
elsif Pkg_Id = System_Tasking_Protected_Objects_Entries then
-- This is the case where we have a protected object with no
-- entries and:
-- - either interrupt handlers with non restricted profile,
-- - or interfaces
-- Note that the types which are used for interrupt handlers
-- (Static/Dynamic_Interrupt_Protection) are derived from
-- Protection_Entries. We pass two null pointers because there
-- is no actual entry, and the initialization procedure needs
-- both Entry_Bodies and Find_Body_Index.
Append_To (Args, Make_Null (Loc));
Append_To (Args, Make_Null (Loc));
end if;
Append_To (L,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of (RTE (Called_Subp), Loc),
Parameter_Associations => Args));
end;
end if;
if Has_Attach_Handler (Ptyp) then
-- We have a list of N Attach_Handler (ProcI, ExprI), and we have to
-- make the following call:
-- Install_Handlers (_object,
-- ((Expr1, Proc1'access), ...., (ExprN, ProcN'access));
-- or, in the case of Ravenscar:
-- Install_Restricted_Handlers
-- (Prio, ((Expr1, Proc1'access), ...., (ExprN, ProcN'access)));
declare
Args : constant List_Id := New_List;
Table : constant List_Id := New_List;
Ritem : Node_Id := First_Rep_Item (Ptyp);
begin
-- Build the Priority parameter (only for ravenscar)
if Restricted then
-- Priority comes from a pragma
if Present (Prio_Var) then
Append_To (Args, New_Occurrence_Of (Prio_Var, Loc));
-- Priority is the default one
else
Append_To (Args,
New_Occurrence_Of
(RTE (RE_Default_Interrupt_Priority), Loc));
end if;
end if;
-- Build the Attach_Handler table argument
while Present (Ritem) loop
if Nkind (Ritem) = N_Pragma
and then Pragma_Name (Ritem) = Name_Attach_Handler
then
declare
Handler : constant Node_Id :=
First (Pragma_Argument_Associations (Ritem));
Interrupt : constant Node_Id := Next (Handler);
Expr : constant Node_Id := Expression (Interrupt);
begin
Append_To (Table,
Make_Aggregate (Loc, Expressions => New_List (
Unchecked_Convert_To
(RTE (RE_System_Interrupt_Id), Expr),
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix =>
Make_Identifier (Loc, Name_uInit),
Selector_Name =>
Duplicate_Subexpr_No_Checks
(Expression (Handler))),
Attribute_Name => Name_Access))));
end;
end if;
Next_Rep_Item (Ritem);
end loop;
-- Append the table argument we just built
Append_To (Args, Make_Aggregate (Loc, Table));
-- Append the Install_Handlers (or Install_Restricted_Handlers)
-- call to the statements.
if Restricted then
-- Call a simplified version of Install_Handlers to be used
-- when the Ravenscar restrictions are in effect
-- (Install_Restricted_Handlers).
Append_To (L,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of
(RTE (RE_Install_Restricted_Handlers), Loc),
Parameter_Associations => Args));
else
if not Uses_Lock_Free (Defining_Identifier (Pdec)) then
-- First, prepends the _object argument
Prepend_To (Args,
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name =>
Make_Identifier (Loc, Name_uObject)),
Attribute_Name => Name_Unchecked_Access));
end if;
-- Then, insert call to Install_Handlers
Append_To (L,
Make_Procedure_Call_Statement (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Install_Handlers), Loc),
Parameter_Associations => Args));
end if;
end;
end if;
return L;
end Make_Initialize_Protection;
---------------------------
-- Make_Task_Create_Call --
---------------------------
function Make_Task_Create_Call (Task_Rec : Entity_Id) return Node_Id is
Loc : constant Source_Ptr := Sloc (Task_Rec);
Args : List_Id;
Ecount : Node_Id;
Name : Node_Id;
Tdec : Node_Id;
Tdef : Node_Id;
Tnam : Name_Id;
Ttyp : Node_Id;
begin
Ttyp := Corresponding_Concurrent_Type (Task_Rec);
Tnam := Chars (Ttyp);
-- Get task declaration. In the case of a task type declaration, this is
-- simply the parent of the task type entity. In the single task
-- declaration, this parent will be the implicit type, and we can find
-- the corresponding single task declaration by searching forward in the
-- declaration list in the tree.
-- Is the test for N_Single_Task_Declaration needed here??? Nodes of
-- this type should have been removed during semantic analysis.
Tdec := Parent (Ttyp);
while Nkind (Tdec) not in
N_Task_Type_Declaration | N_Single_Task_Declaration
loop
Next (Tdec);
end loop;
-- Now we can find the task definition from this declaration
Tdef := Task_Definition (Tdec);
-- Build the parameter list for the call. Note that _Init is the name
-- of the formal for the object to be initialized, which is the task
-- value record itself.
Args := New_List;
-- Priority parameter. Set to Unspecified_Priority unless there is a
-- Priority rep item, in which case we take the value from the rep item.
-- Not used on Ravenscar_EDF profile.
if not (Restricted_Profile and then Task_Dispatching_Policy = 'E') then
if Has_Rep_Item (Ttyp, Name_Priority, Check_Parents => False) then
Append_To (Args,
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name => Make_Identifier (Loc, Name_uPriority)));
else
Append_To (Args,
New_Occurrence_Of (RTE (RE_Unspecified_Priority), Loc));
end if;
end if;
-- Optional Stack parameter
if Restricted_Profile then
-- If the stack has been preallocated by the expander then
-- pass its address. Otherwise, pass a null address.
if Preallocated_Stacks_On_Target then
Append_To (Args,
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name => Make_Identifier (Loc, Name_uStack)),
Attribute_Name => Name_Address));
else
Append_To (Args,
New_Occurrence_Of (RTE (RE_Null_Address), Loc));
end if;
end if;
-- Size parameter. If no Storage_Size pragma is present, then
-- the size is taken from the taskZ variable for the type, which
-- is either Unspecified_Size, or has been reset by the use of
-- a Storage_Size attribute definition clause. If a pragma is
-- present, then the size is taken from the _Size field of the
-- task value record, which was set from the pragma value.
if Present (Tdef) and then Has_Storage_Size_Pragma (Tdef) then
Append_To (Args,
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name => Make_Identifier (Loc, Name_uSize)));
else
Append_To (Args,
New_Occurrence_Of (Storage_Size_Variable (Ttyp), Loc));
end if;
-- Secondary_Stack parameter used for restricted profiles
if Restricted_Profile then
-- If the secondary stack has been allocated by the expander then
-- pass its access pointer. Otherwise, pass null.
if Create_Secondary_Stack_For_Task (Ttyp) then
Append_To (Args,
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name =>
Make_Identifier (Loc, Name_uSecondary_Stack)),
Attribute_Name => Name_Unrestricted_Access));
else
Append_To (Args, Make_Null (Loc));
end if;
end if;
-- Secondary_Stack_Size parameter. Set RE_Unspecified_Size unless there
-- is a Secondary_Stack_Size pragma, in which case take the value from
-- the pragma. If the restriction No_Secondary_Stack is active then a
-- size of 0 is passed regardless to prevent the allocation of the
-- unused stack.
if Restriction_Active (No_Secondary_Stack) then
Append_To (Args, Make_Integer_Literal (Loc, 0));
elsif Has_Rep_Pragma
(Ttyp, Name_Secondary_Stack_Size, Check_Parents => False)
then
Append_To (Args,
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name =>
Make_Identifier (Loc, Name_uSecondary_Stack_Size)));
else
Append_To (Args,
New_Occurrence_Of (RTE (RE_Unspecified_Size), Loc));
end if;
-- Task_Info parameter. Set to Unspecified_Task_Info unless there is a
-- Task_Info pragma, in which case we take the value from the pragma.
if Has_Rep_Pragma (Ttyp, Name_Task_Info, Check_Parents => False) then
Append_To (Args,
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name => Make_Identifier (Loc, Name_uTask_Info)));
else
Append_To (Args,
New_Occurrence_Of (RTE (RE_Unspecified_Task_Info), Loc));
end if;
-- CPU parameter. Set to Unspecified_CPU unless there is a CPU rep item,
-- in which case we take the value from the rep item. The parameter is
-- passed as an Integer because in the case of unspecified CPU the
-- value is not in the range of CPU_Range.
if Has_Rep_Item (Ttyp, Name_CPU, Check_Parents => False) then
Append_To (Args,
Convert_To (Standard_Integer,
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name => Make_Identifier (Loc, Name_uCPU))));
else
Append_To (Args,
New_Occurrence_Of (RTE (RE_Unspecified_CPU), Loc));
end if;
if not Restricted_Profile or else Task_Dispatching_Policy = 'E' then
-- Deadline parameter. If no Relative_Deadline pragma is present,
-- then the deadline is Time_Span_Zero. If a pragma is present, then
-- the deadline is taken from the _Relative_Deadline field of the
-- task value record, which was set from the pragma value. Note that
-- this parameter must not be generated for the restricted profiles
-- since Ravenscar does not allow deadlines.
-- Case where pragma Relative_Deadline applies: use given value
if Present (Tdef) and then Has_Relative_Deadline_Pragma (Tdef) then
Append_To (Args,
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name =>
Make_Identifier (Loc, Name_uRelative_Deadline)));
-- No pragma Relative_Deadline apply to the task
else
Append_To (Args,
New_Occurrence_Of (RTE (RE_Time_Span_Zero), Loc));
end if;
end if;
if not Restricted_Profile then
-- Dispatching_Domain parameter. If no Dispatching_Domain rep item is
-- present, then the dispatching domain is null. If a rep item is
-- present, then the dispatching domain is taken from the
-- _Dispatching_Domain field of the task value record, which was set
-- from the rep item value.
-- Case where Dispatching_Domain rep item applies: use given value
if Has_Rep_Item
(Ttyp, Name_Dispatching_Domain, Check_Parents => False)
then
Append_To (Args,
Make_Selected_Component (Loc,
Prefix =>
Make_Identifier (Loc, Name_uInit),
Selector_Name =>
Make_Identifier (Loc, Name_uDispatching_Domain)));
-- No pragma or aspect Dispatching_Domain applies to the task
else
Append_To (Args, Make_Null (Loc));
end if;
-- Number of entries. This is an expression of the form:
-- n + _Init.a'Length + _Init.a'B'Length + ...
-- where a,b... are the entry family names for the task definition
Ecount :=
Build_Entry_Count_Expression
(Ttyp,
Component_Items
(Component_List
(Type_Definition
(Parent (Corresponding_Record_Type (Ttyp))))),
Loc);
Append_To (Args, Ecount);
-- Master parameter. This is a reference to the _Master parameter of
-- the initialization procedure, except in the case of the pragma
-- Restrictions (No_Task_Hierarchy) where the value is fixed to
-- System.Tasking.Library_Task_Level.
if Restriction_Active (No_Task_Hierarchy) = False then
Append_To (Args, Make_Identifier (Loc, Name_uMaster));
else
Append_To (Args, Make_Integer_Literal (Loc, Library_Task_Level));
end if;
end if;
-- State parameter. This is a pointer to the task body procedure. The
-- required value is obtained by taking 'Unrestricted_Access of the task
-- body procedure and converting it (with an unchecked conversion) to
-- the type required by the task kernel. For further details, see the
-- description of Expand_N_Task_Body. We use 'Unrestricted_Access rather
-- than 'Address in order to avoid creating trampolines.
declare
Body_Proc : constant Node_Id := Get_Task_Body_Procedure (Ttyp);
Subp_Ptr_Typ : constant Node_Id :=
Create_Itype (E_Access_Subprogram_Type, Tdec);
Ref : constant Node_Id := Make_Itype_Reference (Loc);
begin
Set_Directly_Designated_Type (Subp_Ptr_Typ, Body_Proc);
Set_Etype (Subp_Ptr_Typ, Subp_Ptr_Typ);
-- Be sure to freeze a reference to the access-to-subprogram type,
-- otherwise gigi will complain that it's in the wrong scope, because
-- it's actually inside the init procedure for the record type that
-- corresponds to the task type.
Set_Itype (Ref, Subp_Ptr_Typ);
Append_Freeze_Action (Task_Rec, Ref);
Append_To (Args,
Unchecked_Convert_To (RTE (RE_Task_Procedure_Access),
Make_Qualified_Expression (Loc,
Subtype_Mark => New_Occurrence_Of (Subp_Ptr_Typ, Loc),
Expression =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Body_Proc, Loc),
Attribute_Name => Name_Unrestricted_Access))));
end;
-- Discriminants parameter. This is just the address of the task
-- value record itself (which contains the discriminant values
Append_To (Args,
Make_Attribute_Reference (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Attribute_Name => Name_Address));
-- Elaborated parameter. This is an access to the elaboration Boolean
Append_To (Args,
Make_Attribute_Reference (Loc,
Prefix => Make_Identifier (Loc, New_External_Name (Tnam, 'E')),
Attribute_Name => Name_Unchecked_Access));
-- Add Chain parameter (not done for sequential elaboration policy, see
-- comment for Create_Restricted_Task_Sequential in s-tarest.ads).
if Partition_Elaboration_Policy /= 'S' then
Append_To (Args, Make_Identifier (Loc, Name_uChain));
end if;
-- Task name parameter. Take this from the _Task_Id parameter to the
-- init call unless there is a Task_Name pragma, in which case we take
-- the value from the pragma.
if Has_Rep_Pragma (Ttyp, Name_Task_Name, Check_Parents => False) then
-- Copy expression in full, because it may be dynamic and have
-- side effects.
Append_To (Args,
New_Copy_Tree
(Expression
(First
(Pragma_Argument_Associations
(Get_Rep_Pragma
(Ttyp, Name_Task_Name, Check_Parents => False))))));
else
Append_To (Args, Make_Identifier (Loc, Name_uTask_Name));
end if;
-- Created_Task parameter. This is the _Task_Id field of the task
-- record value
Append_To (Args,
Make_Selected_Component (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Selector_Name => Make_Identifier (Loc, Name_uTask_Id)));
declare
Create_RE : RE_Id;
begin
if Restricted_Profile then
if Partition_Elaboration_Policy = 'S' then
Create_RE := RE_Create_Restricted_Task_Sequential;
else
Create_RE := RE_Create_Restricted_Task;
end if;
else
Create_RE := RE_Create_Task;
end if;
Name := New_Occurrence_Of (RTE (Create_RE), Loc);
end;
return
Make_Procedure_Call_Statement (Loc,
Name => Name,
Parameter_Associations => Args);
end Make_Task_Create_Call;
------------------------------
-- Next_Protected_Operation --
------------------------------
function Next_Protected_Operation (N : Node_Id) return Node_Id is
Next_Op : Node_Id;
begin
-- Check whether there is a subsequent body for a protected operation
-- in the current protected body. In Ada2012 that includes expression
-- functions that are completions.
Next_Op := Next (N);
while Present (Next_Op)
and then Nkind (Next_Op) not in
N_Subprogram_Body | N_Entry_Body | N_Expression_Function
loop
Next (Next_Op);
end loop;
return Next_Op;
end Next_Protected_Operation;
---------------------
-- Null_Statements --
---------------------
function Null_Statements (Stats : List_Id) return Boolean is
Stmt : Node_Id;
begin
Stmt := First (Stats);
while Nkind (Stmt) /= N_Empty
and then (Nkind (Stmt) in N_Null_Statement | N_Label
or else
(Nkind (Stmt) = N_Pragma
and then
Pragma_Name_Unmapped (Stmt) in Name_Unreferenced
| Name_Unmodified
| Name_Warnings))
loop
Next (Stmt);
end loop;
return Nkind (Stmt) = N_Empty;
end Null_Statements;
--------------------------
-- Parameter_Block_Pack --
--------------------------
function Parameter_Block_Pack
(Loc : Source_Ptr;
Blk_Typ : Entity_Id;
Actuals : List_Id;
Formals : List_Id;
Decls : List_Id;
Stmts : List_Id) return Entity_Id
is
Actual : Entity_Id;
Expr : Node_Id := Empty;
Formal : Entity_Id;
Has_Param : Boolean := False;
P : Entity_Id;
Params : List_Id;
Temp_Asn : Node_Id;
Temp_Nam : Node_Id;
begin
Actual := First (Actuals);
Formal := Defining_Identifier (First (Formals));
Params := New_List;
while Present (Actual) loop
if Is_By_Copy_Type (Etype (Actual)) then
-- Generate:
-- Jnn : aliased <formal-type>
Temp_Nam := Make_Temporary (Loc, 'J');
Append_To (Decls,
Make_Object_Declaration (Loc,
Aliased_Present => True,
Defining_Identifier => Temp_Nam,
Object_Definition =>
New_Occurrence_Of (Etype (Formal), Loc)));
-- The object is initialized with an explicit assignment
-- later. Indicate that it does not need an initialization
-- to prevent spurious warnings if the type excludes null.
Set_No_Initialization (Last (Decls));
if Ekind (Formal) /= E_Out_Parameter then
-- Generate:
-- Jnn := <actual>
Temp_Asn :=
New_Occurrence_Of (Temp_Nam, Loc);
Set_Assignment_OK (Temp_Asn);
Append_To (Stmts,
Make_Assignment_Statement (Loc,
Name => Temp_Asn,
Expression => New_Copy_Tree (Actual)));
end if;
-- If the actual is not controlling, generate:
-- Jnn'unchecked_access
-- and add it to aggegate for access to formals. Note that the
-- actual may be by-copy but still be a controlling actual if it
-- is an access to class-wide interface.
if not Is_Controlling_Actual (Actual) then
Append_To (Params,
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Unchecked_Access,
Prefix => New_Occurrence_Of (Temp_Nam, Loc)));
Has_Param := True;
end if;
-- The controlling parameter is omitted
else
if not Is_Controlling_Actual (Actual) then
Append_To (Params,
Make_Reference (Loc, New_Copy_Tree (Actual)));
Has_Param := True;
end if;
end if;
Next_Actual (Actual);
Next_Formal_With_Extras (Formal);
end loop;
if Has_Param then
Expr := Make_Aggregate (Loc, Params);
end if;
-- Generate:
-- P : Ann := (
-- J1'unchecked_access;
-- <actual2>'reference;
-- ...);
P := Make_Temporary (Loc, 'P');
Append_To (Decls,
Make_Object_Declaration (Loc,
Defining_Identifier => P,
Object_Definition => New_Occurrence_Of (Blk_Typ, Loc),
Expression => Expr));
return P;
end Parameter_Block_Pack;
----------------------------
-- Parameter_Block_Unpack --
----------------------------
function Parameter_Block_Unpack
(Loc : Source_Ptr;
P : Entity_Id;
Actuals : List_Id;
Formals : List_Id) return List_Id
is
Actual : Entity_Id;
Asnmt : Node_Id;
Formal : Entity_Id;
Has_Asnmt : Boolean := False;
Result : constant List_Id := New_List;
begin
Actual := First (Actuals);
Formal := Defining_Identifier (First (Formals));
while Present (Actual) loop
if Is_By_Copy_Type (Etype (Actual))
and then Ekind (Formal) /= E_In_Parameter
then
-- Generate:
-- <actual> := P.<formal>;
Asnmt :=
Make_Assignment_Statement (Loc,
Name =>
New_Copy (Actual),
Expression =>
Make_Explicit_Dereference (Loc,
Make_Selected_Component (Loc,
Prefix =>
New_Occurrence_Of (P, Loc),
Selector_Name =>
Make_Identifier (Loc, Chars (Formal)))));
Set_Assignment_OK (Name (Asnmt));
Append_To (Result, Asnmt);
Has_Asnmt := True;
end if;
Next_Actual (Actual);
Next_Formal_With_Extras (Formal);
end loop;
if Has_Asnmt then
return Result;
else
return New_List (Make_Null_Statement (Loc));
end if;
end Parameter_Block_Unpack;
---------------------
-- Reset_Scopes_To --
---------------------
procedure Reset_Scopes_To (Bod : Node_Id; E : Entity_Id) is
function Reset_Scope (N : Node_Id) return Traverse_Result;
-- Temporaries may have been declared during expansion of the procedure
-- created for an entry body or an accept alternative. Indicate that
-- their scope is the new body, to ensure proper generation of uplevel
-- references where needed during unnesting.
procedure Reset_Scopes is new Traverse_Proc (Reset_Scope);
-----------------
-- Reset_Scope --
-----------------
function Reset_Scope (N : Node_Id) return Traverse_Result is
Decl : Node_Id;
begin
-- If this is a block statement with an Identifier, it forms a scope,
-- so we want to reset its scope but not look inside.
if N /= Bod
and then Nkind (N) = N_Block_Statement
and then Present (Identifier (N))
then
Set_Scope (Entity (Identifier (N)), E);
return Skip;
-- Ditto for a package declaration or a full type declaration, etc.
elsif (Nkind (N) = N_Package_Declaration
and then N /= Specification (N))
or else Nkind (N) in N_Declaration
or else Nkind (N) in N_Renaming_Declaration
then
Set_Scope (Defining_Entity (N), E);
return Skip;
elsif N = Bod then
-- Scan declarations in new body. Declarations in the statement
-- part will be handled during later traversal.
Decl := First (Declarations (N));
while Present (Decl) loop
Reset_Scopes (Decl);
Next (Decl);
end loop;
elsif Nkind (N) = N_Freeze_Entity then
-- Scan the actions associated with a freeze node, which may
-- actually be declarations with entities that need to have
-- their scopes reset.
Decl := First (Actions (N));
while Present (Decl) loop
Reset_Scopes (Decl);
Next (Decl);
end loop;
elsif N /= Bod and then Nkind (N) in N_Proper_Body then
-- A subprogram without a separate declaration may be encountered,
-- and we need to reset the subprogram's entity's scope.
if Nkind (N) = N_Subprogram_Body then
Set_Scope (Defining_Entity (Specification (N)), E);
end if;
return Skip;
end if;
return OK;
end Reset_Scope;
-- Start of processing for Reset_Scopes_To
begin
Reset_Scopes (Bod);
end Reset_Scopes_To;
----------------------
-- Set_Discriminals --
----------------------
procedure Set_Discriminals (Dec : Node_Id) is
D : Entity_Id;
Pdef : Entity_Id;
D_Minal : Entity_Id;
begin
pragma Assert (Nkind (Dec) = N_Protected_Type_Declaration);
Pdef := Defining_Identifier (Dec);
if Has_Discriminants (Pdef) then
D := First_Discriminant (Pdef);
while Present (D) loop
D_Minal :=
Make_Defining_Identifier (Sloc (D),
Chars => New_External_Name (Chars (D), 'D'));
Mutate_Ekind (D_Minal, E_Constant);
Set_Etype (D_Minal, Etype (D));
Set_Scope (D_Minal, Pdef);
Set_Discriminal (D, D_Minal);
Set_Discriminal_Link (D_Minal, D);
Next_Discriminant (D);
end loop;
end if;
end Set_Discriminals;
-----------------------
-- Trivial_Accept_OK --
-----------------------
function Trivial_Accept_OK return Boolean is
begin
case Opt.Task_Dispatching_Policy is
-- If we have the default task dispatching policy in effect, we can
-- definitely do the optimization (one way of looking at this is to
-- think of the formal definition of the default policy being allowed
-- to run any task it likes after a rendezvous, so even if notionally
-- a full rescheduling occurs, we can say that our dispatching policy
-- (i.e. the default dispatching policy) reorders the queue to be the
-- same as just before the call.
when ' ' =>
return True;
-- FIFO_Within_Priorities certainly does not permit this
-- optimization since the Rendezvous is a scheduling action that may
-- require some other task to be run.
when 'F' =>
return False;
-- For now, disallow the optimization for all other policies. This
-- may be over-conservative, but it is certainly not incorrect.
when others =>
return False;
end case;
end Trivial_Accept_OK;
end Exp_Ch9;