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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- E X P _ I N T R --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-2022, 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 Expander; use Expander;
with Exp_Atag; use Exp_Atag;
with Exp_Ch6; use Exp_Ch6;
with Exp_Ch7; use Exp_Ch7;
with Exp_Ch11; use Exp_Ch11;
with Exp_Code; use Exp_Code;
with Exp_Fixd; use Exp_Fixd;
with Exp_Util; use Exp_Util;
with Freeze; use Freeze;
with Inline; use Inline;
with Nmake; use Nmake;
with Nlists; use Nlists;
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_Eval; use Sem_Eval;
with Sem_Res; use Sem_Res;
with Sem_Type; use Sem_Type;
with Sem_Util; use Sem_Util;
with Sinfo; use Sinfo;
with Sinfo.Nodes; use Sinfo.Nodes;
with Sinfo.Utils; use Sinfo.Utils;
with Sinput; use Sinput;
with Snames; use Snames;
with Stand; use Stand;
with Tbuild; use Tbuild;
with Uintp; use Uintp;
package body Exp_Intr is
-----------------------
-- Local Subprograms --
-----------------------
procedure Expand_Binary_Operator_Call (N : Node_Id);
-- Expand a call to an intrinsic arithmetic operator when the operand
-- types or sizes are not identical.
procedure Expand_Dispatching_Constructor_Call (N : Node_Id);
-- Expand a call to an instantiation of Generic_Dispatching_Constructor
-- into a dispatching call to the actual subprogram associated with the
-- Constructor formal subprogram, passing it the Parameters actual of
-- the call to the instantiation and dispatching based on call's Tag
-- parameter.
procedure Expand_Exception_Call (N : Node_Id; Ent : RE_Id);
-- Expand a call to Exception_Information/Message/Name. The first
-- parameter, N, is the node for the function call, and Ent is the
-- entity for the corresponding routine in the Ada.Exceptions package.
procedure Expand_Import_Call (N : Node_Id);
-- Expand a call to Import_Address/Longest_Integer/Value. The parameter
-- N is the node for the function call.
procedure Expand_Shift (N : Node_Id; E : Entity_Id; K : Node_Kind);
-- Expand an intrinsic shift operation, N and E are from the call to
-- Expand_Intrinsic_Call (call node and subprogram spec entity) and
-- K is the kind for the shift node
procedure Expand_Unc_Conversion (N : Node_Id; E : Entity_Id);
-- Expand a call to an instantiation of Unchecked_Conversion into a node
-- N_Unchecked_Type_Conversion.
procedure Expand_Unc_Deallocation (N : Node_Id);
-- Expand a call to an instantiation of Unchecked_Deallocation into a node
-- N_Free_Statement and appropriate context.
procedure Expand_To_Address (N : Node_Id);
procedure Expand_To_Pointer (N : Node_Id);
-- Expand a call to corresponding function, declared in an instance of
-- System.Address_To_Access_Conversions.
procedure Expand_Source_Info (N : Node_Id; Nam : Name_Id);
-- Rewrite the node as the appropriate string literal or positive
-- constant. Nam is the name of one of the intrinsics declared in
-- GNAT.Source_Info; see g-souinf.ads for documentation of these
-- intrinsics.
---------------------
-- Add_Source_Info --
---------------------
procedure Add_Source_Info
(Buf : in out Bounded_String;
Loc : Source_Ptr;
Nam : Name_Id)
is
begin
case Nam is
when Name_Line =>
Append (Buf, Nat (Get_Logical_Line_Number (Loc)));
when Name_File =>
Append (Buf, Reference_Name (Get_Source_File_Index (Loc)));
when Name_Source_Location =>
Build_Location_String (Buf, Loc);
when Name_Enclosing_Entity =>
-- Skip enclosing blocks to reach enclosing unit
declare
Ent : Entity_Id := Current_Scope;
begin
while Present (Ent) loop
exit when Ekind (Ent) not in E_Block | E_Loop;
Ent := Scope (Ent);
end loop;
-- Ent now points to the relevant defining entity
Append_Entity_Name (Buf, Ent);
end;
when Name_Compilation_ISO_Date =>
Append (Buf, Opt.Compilation_Time (1 .. 10));
when Name_Compilation_Date =>
declare
subtype S13 is String (1 .. 3);
Months : constant array (1 .. 12) of S13 :=
("Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec");
M1 : constant Character := Opt.Compilation_Time (6);
M2 : constant Character := Opt.Compilation_Time (7);
MM : constant Natural range 1 .. 12 :=
(Character'Pos (M1) - Character'Pos ('0')) * 10 +
(Character'Pos (M2) - Character'Pos ('0'));
begin
-- Reformat ISO date into MMM DD YYYY (__DATE__) format
Append (Buf, Months (MM));
Append (Buf, ' ');
Append (Buf, Opt.Compilation_Time (9 .. 10));
Append (Buf, ' ');
Append (Buf, Opt.Compilation_Time (1 .. 4));
end;
when Name_Compilation_Time =>
Append (Buf, Opt.Compilation_Time (12 .. 19));
when others =>
raise Program_Error;
end case;
end Add_Source_Info;
---------------------------------
-- Expand_Binary_Operator_Call --
---------------------------------
procedure Expand_Binary_Operator_Call (N : Node_Id) is
T1 : constant Entity_Id := Underlying_Type (Etype (Left_Opnd (N)));
T2 : constant Entity_Id := Underlying_Type (Etype (Right_Opnd (N)));
TR : constant Entity_Id := Etype (N);
T3 : Entity_Id;
Res : Node_Id;
Siz : constant Uint := UI_Max (RM_Size (T1), RM_Size (T2));
-- Maximum of operand sizes
begin
-- Nothing to do if the operands have the same modular type
if Base_Type (T1) = Base_Type (T2)
and then Is_Modular_Integer_Type (T1)
then
return;
end if;
-- Use the appropriate type for the size
if Siz <= 32 then
T3 := RTE (RE_Unsigned_32);
elsif Siz <= 64 then
T3 := RTE (RE_Unsigned_64);
else pragma Assert (Siz <= 128);
T3 := RTE (RE_Unsigned_128);
end if;
-- Copy operator node, and reset type and entity fields, for
-- subsequent reanalysis.
Res := New_Copy (N);
Set_Etype (Res, T3);
case Nkind (N) is
when N_Op_And => Set_Entity (Res, Standard_Op_And);
when N_Op_Or => Set_Entity (Res, Standard_Op_Or);
when N_Op_Xor => Set_Entity (Res, Standard_Op_Xor);
when others => raise Program_Error;
end case;
-- Convert operands to large enough intermediate type
Set_Left_Opnd (Res,
Unchecked_Convert_To (T3, Relocate_Node (Left_Opnd (N))));
Set_Right_Opnd (Res,
Unchecked_Convert_To (T3, Relocate_Node (Right_Opnd (N))));
-- Analyze and resolve result formed by conversion to target type
Rewrite (N, Unchecked_Convert_To (TR, Res));
Analyze_And_Resolve (N, TR);
end Expand_Binary_Operator_Call;
-----------------------------------------
-- Expand_Dispatching_Constructor_Call --
-----------------------------------------
-- Transform a call to an instantiation of Generic_Dispatching_Constructor
-- of the form:
-- GDC_Instance (The_Tag, Parameters'Access)
-- to a class-wide conversion of a dispatching call to the actual
-- associated with the formal subprogram Construct, designating The_Tag
-- as the controlling tag of the call:
-- T'Class (Construct'Actual (Params)) -- Controlling tag is The_Tag
-- which will eventually be expanded to the following:
-- T'Class (The_Tag.all (Construct'Actual'Index).all (Params))
-- A class-wide membership test is also generated, preceding the call, to
-- ensure that the controlling tag denotes a type in T'Class.
procedure Expand_Dispatching_Constructor_Call (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Tag_Arg : constant Node_Id := First_Actual (N);
Param_Arg : constant Node_Id := Next_Actual (Tag_Arg);
Subp_Decl : constant Node_Id := Parent (Parent (Entity (Name (N))));
Inst_Pkg : constant Node_Id := Parent (Subp_Decl);
Act_Rename : Node_Id;
Act_Constr : Entity_Id;
Iface_Tag : Node_Id := Empty;
Cnstr_Call : Node_Id;
Result_Typ : Entity_Id;
begin
pragma Assert (Is_Class_Wide_Type (Etype (Entity (Name (N)))));
-- Report case where we know that the generated code is wrong; that
-- is a dispatching constructor call whose controlling type has tasks
-- but its root type does not have tasks. In such case the constructor
-- subprogram of the root type does not have extra formals but the
-- constructor of the derivation must have extra formals.
if not Global_No_Tasking
and then not No_Run_Time_Mode
and then Is_Build_In_Place_Function (Entity (Name (N)))
and then not Has_Task (Root_Type (Etype (Entity (Name (N)))))
and then not Has_Aspect (Root_Type (Etype (Entity (Name (N)))),
Aspect_No_Task_Parts)
then
-- Case 1: Explicit tag reference (which allows static check)
if Nkind (Tag_Arg) = N_Identifier
and then Present (Entity (Tag_Arg))
and then Is_Tag (Entity (Tag_Arg))
then
if Has_Task (Related_Type (Entity (Tag_Arg))) then
Error_Msg_N ("unsupported dispatching constructor call", N);
Error_Msg_NE
("\work around this problem by defining task component "
& "type& using access-to-task-type",
N, Related_Type (Entity (Tag_Arg)));
end if;
-- Case 2: Dynamic tag which may fail at run time
else
Error_Msg_N
("unsupported dispatching constructor call if the type "
& "of the built object has task components??", N);
Error_Msg_Sloc := Sloc (Root_Type (Etype (Entity (Name (N)))));
Error_Msg_NE
("\work around this by adding ''with no_task_parts'' to "
& "the declaration of the root type& defined#???",
N, Root_Type (Etype (Entity (Name (N)))));
end if;
end if;
-- Remove side effects from tag argument early, before rewriting
-- the dispatching constructor call, as Remove_Side_Effects relies
-- on Tag_Arg's Parent link properly attached to the tree (once the
-- call is rewritten, the Parent is inconsistent as it points to the
-- rewritten node, which is not the syntactic parent of the Tag_Arg
-- anymore).
Remove_Side_Effects (Tag_Arg);
-- Check that we have a proper tag
Insert_Action (N,
Make_Implicit_If_Statement (N,
Condition => Make_Op_Eq (Loc,
Left_Opnd => New_Copy_Tree (Tag_Arg),
Right_Opnd => New_Occurrence_Of (RTE (RE_No_Tag), Loc)),
Then_Statements => New_List (
Make_Raise_Statement (Loc,
New_Occurrence_Of (RTE (RE_Tag_Error), Loc)))));
-- Check that it is not the tag of an abstract type
Insert_Action (N,
Make_Implicit_If_Statement (N,
Condition => Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Is_Abstract), Loc),
Parameter_Associations => New_List (New_Copy_Tree (Tag_Arg))),
Then_Statements => New_List (
Make_Raise_Statement (Loc,
New_Occurrence_Of (RTE (RE_Tag_Error), Loc)))));
-- The subprogram is the third actual in the instantiation, and is
-- retrieved from the corresponding renaming declaration. However,
-- freeze nodes may appear before, so we retrieve the declaration
-- with an explicit loop.
Act_Rename := First (Visible_Declarations (Inst_Pkg));
while Nkind (Act_Rename) /= N_Subprogram_Renaming_Declaration loop
Next (Act_Rename);
end loop;
Act_Constr := Entity (Name (Act_Rename));
Result_Typ := Class_Wide_Type (Etype (Act_Constr));
-- Check that the accessibility level of the tag is no deeper than that
-- of the constructor function (unless CodePeer_Mode).
if not CodePeer_Mode then
Insert_Action (N,
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Gt (Loc,
Left_Opnd =>
Build_Get_Access_Level (Loc, New_Copy_Tree (Tag_Arg)),
Right_Opnd =>
Make_Integer_Literal
(Loc, Scope_Depth_Default_0 (Act_Constr))),
Then_Statements => New_List (
Make_Raise_Statement (Loc,
New_Occurrence_Of (RTE (RE_Tag_Error), Loc)))));
end if;
if Is_Interface (Etype (Act_Constr)) then
-- If the result type is not known to be a parent of Tag_Arg then we
-- need to locate the tag of the secondary dispatch table.
if not Is_Ancestor (Etype (Result_Typ), Etype (Tag_Arg),
Use_Full_View => True)
and then Tagged_Type_Expansion
then
-- Obtain the reference to the Ada.Tags service before generating
-- the Object_Declaration node to ensure that if this service is
-- not available in the runtime then we generate a clear error.
declare
Fname : constant Node_Id :=
New_Occurrence_Of (RTE (RE_Secondary_Tag), Loc);
begin
pragma Assert (not Is_Interface (Etype (Tag_Arg)));
-- The tag is the first entry in the dispatch table of the
-- return type of the constructor.
Iface_Tag :=
Make_Object_Declaration (Loc,
Defining_Identifier => Make_Temporary (Loc, 'V'),
Object_Definition =>
New_Occurrence_Of (RTE (RE_Tag), Loc),
Expression =>
Make_Function_Call (Loc,
Name => Fname,
Parameter_Associations => New_List (
Relocate_Node (Tag_Arg),
New_Occurrence_Of
(Node (First_Elmt
(Access_Disp_Table (Etype (Act_Constr)))),
Loc))));
Insert_Action (N, Iface_Tag);
end;
end if;
end if;
-- Create the call to the actual Constructor function
Cnstr_Call :=
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Act_Constr, Loc),
Parameter_Associations => New_List (Relocate_Node (Param_Arg)));
-- Establish its controlling tag from the tag passed to the instance
-- The tag may be given by a function call, in which case a temporary
-- should be generated now, to prevent out-of-order insertions during
-- the expansion of that call when stack-checking is enabled.
if Present (Iface_Tag) then
Set_Controlling_Argument (Cnstr_Call,
New_Occurrence_Of (Defining_Identifier (Iface_Tag), Loc));
else
Set_Controlling_Argument (Cnstr_Call,
Relocate_Node (Tag_Arg));
end if;
-- Rewrite and analyze the call to the instance as a class-wide
-- conversion of the call to the actual constructor. When the result
-- type is a class-wide interface type this conversion is required to
-- force the displacement of the pointer to the object to reference the
-- corresponding dispatch table.
Rewrite (N, Convert_To (Result_Typ, Cnstr_Call));
-- Do not generate a run-time check on the built object if tag
-- checks are suppressed for the result type or tagged type expansion
-- is disabled or if CodePeer_Mode.
if Tag_Checks_Suppressed (Etype (Result_Typ))
or else not Tagged_Type_Expansion
or else CodePeer_Mode
then
null;
-- Generate a class-wide membership test to ensure that the call's tag
-- argument denotes a type within the class. We must keep separate the
-- case in which the Result_Type of the constructor function is a tagged
-- type from the case in which it is an abstract interface because the
-- run-time subprogram required to check these cases differ (and have
-- one difference in their parameters profile).
-- Call CW_Membership if the Result_Type is a tagged type to look for
-- the tag in the table of ancestor tags.
elsif not Is_Interface (Result_Typ) then
Insert_Action (N,
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Not (Loc,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_CW_Membership), Loc),
Parameter_Associations => New_List (
New_Copy_Tree (Tag_Arg),
New_Occurrence_Of (
Node (First_Elmt (Access_Disp_Table (
Root_Type (Result_Typ)))), Loc)))),
Then_Statements =>
New_List (
Make_Raise_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Tag_Error), Loc)))));
-- Call IW_Membership test if the Result_Type is an abstract interface
-- to look for the tag in the table of interface tags.
else
Insert_Action (N,
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Not (Loc,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_IW_Membership), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Copy_Tree (Tag_Arg),
Attribute_Name => Name_Address),
New_Occurrence_Of (
Node (First_Elmt (Access_Disp_Table (
Root_Type (Result_Typ)))), Loc)))),
Then_Statements =>
New_List (
Make_Raise_Statement (Loc,
Name => New_Occurrence_Of (RTE (RE_Tag_Error), Loc)))));
end if;
Analyze_And_Resolve (N, Etype (Act_Constr));
end Expand_Dispatching_Constructor_Call;
---------------------------
-- Expand_Exception_Call --
---------------------------
-- If the function call is not within an exception handler, then the call
-- is replaced by a null string. Otherwise the appropriate routine in
-- Ada.Exceptions is called passing the choice parameter specification
-- from the enclosing handler. If the enclosing handler lacks a choice
-- parameter, then one is supplied.
procedure Expand_Exception_Call (N : Node_Id; Ent : RE_Id) is
Loc : constant Source_Ptr := Sloc (N);
P : Node_Id;
E : Entity_Id;
begin
-- Climb up parents to see if we are in exception handler
P := Parent (N);
loop
-- Case of not in exception handler, replace by null string
if No (P) then
Rewrite (N,
Make_String_Literal (Loc,
Strval => ""));
exit;
-- Case of in exception handler
elsif Nkind (P) = N_Exception_Handler then
-- Handler cannot be used for a local raise, and furthermore, this
-- is a violation of the No_Exception_Propagation restriction.
Set_Local_Raise_Not_OK (P);
Check_Restriction (No_Exception_Propagation, N);
-- If no choice parameter present, then put one there. Note that
-- we do not need to put it on the entity chain, since no one will
-- be referencing it by normal visibility methods.
if No (Choice_Parameter (P)) then
E := Make_Temporary (Loc, 'E');
Set_Choice_Parameter (P, E);
Mutate_Ekind (E, E_Variable);
Set_Etype (E, RTE (RE_Exception_Occurrence));
Set_Scope (E, Current_Scope);
end if;
Rewrite (N,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (Ent), Loc),
Parameter_Associations => New_List (
New_Occurrence_Of (Choice_Parameter (P), Loc))));
exit;
-- Keep climbing
else
P := Parent (P);
end if;
end loop;
Analyze_And_Resolve (N, Standard_String);
end Expand_Exception_Call;
------------------------
-- Expand_Import_Call --
------------------------
-- The function call must have a static string as its argument. We create
-- a dummy variable which uses this string as the external name in an
-- Import pragma. The result is then obtained as the address of this
-- dummy variable, converted to the appropriate target type.
procedure Expand_Import_Call (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Ent : constant Entity_Id := Entity (Name (N));
Str : constant Node_Id := First_Actual (N);
Dum : constant Entity_Id := Make_Temporary (Loc, 'D');
begin
Insert_Actions (N, New_List (
Make_Object_Declaration (Loc,
Defining_Identifier => Dum,
Object_Definition =>
New_Occurrence_Of (Standard_Character, Loc)),
Make_Pragma (Loc,
Chars => Name_Import,
Pragma_Argument_Associations => New_List (
Make_Pragma_Argument_Association (Loc,
Expression => Make_Identifier (Loc, Name_Ada)),
Make_Pragma_Argument_Association (Loc,
Expression => Make_Identifier (Loc, Chars (Dum))),
Make_Pragma_Argument_Association (Loc,
Chars => Name_Link_Name,
Expression => Relocate_Node (Str))))));
Rewrite (N,
Unchecked_Convert_To (Etype (Ent),
Make_Attribute_Reference (Loc,
Prefix => Make_Identifier (Loc, Chars (Dum)),
Attribute_Name => Name_Address)));
Analyze_And_Resolve (N, Etype (Ent));
end Expand_Import_Call;
---------------------------
-- Expand_Intrinsic_Call --
---------------------------
procedure Expand_Intrinsic_Call (N : Node_Id; E : Entity_Id) is
Nam : Name_Id;
begin
-- If an external name is specified for the intrinsic, it is handled
-- by the back-end: leave the call node unchanged for now.
if Present (Interface_Name (E)) then
return;
end if;
-- If the intrinsic subprogram is generic, gets its original name
if Present (Parent (E))
and then Present (Generic_Parent (Parent (E)))
then
Nam := Chars (Generic_Parent (Parent (E)));
else
Nam := Chars (E);
end if;
if Nam = Name_Asm then
Expand_Asm_Call (N);
elsif Nam = Name_Divide then
Expand_Decimal_Divide_Call (N);
elsif Nam = Name_Exception_Information then
Expand_Exception_Call (N, RE_Exception_Information);
elsif Nam = Name_Exception_Message then
Expand_Exception_Call (N, RE_Exception_Message);
elsif Nam = Name_Exception_Name then
Expand_Exception_Call (N, RE_Exception_Name_Simple);
elsif Nam = Name_Generic_Dispatching_Constructor then
Expand_Dispatching_Constructor_Call (N);
elsif Nam in Name_Import_Address
| Name_Import_Largest_Value
| Name_Import_Value
then
Expand_Import_Call (N);
elsif Nam = Name_Rotate_Left then
Expand_Shift (N, E, N_Op_Rotate_Left);
elsif Nam = Name_Rotate_Right then
Expand_Shift (N, E, N_Op_Rotate_Right);
elsif Nam = Name_Shift_Left then
Expand_Shift (N, E, N_Op_Shift_Left);
elsif Nam = Name_Shift_Right then
Expand_Shift (N, E, N_Op_Shift_Right);
elsif Nam = Name_Shift_Right_Arithmetic then
Expand_Shift (N, E, N_Op_Shift_Right_Arithmetic);
elsif Nam = Name_Unchecked_Conversion then
Expand_Unc_Conversion (N, E);
elsif Nam = Name_Unchecked_Deallocation then
Expand_Unc_Deallocation (N);
elsif Nam = Name_To_Address then
Expand_To_Address (N);
elsif Nam = Name_To_Pointer then
Expand_To_Pointer (N);
elsif Nam in Name_File
| Name_Line
| Name_Source_Location
| Name_Enclosing_Entity
| Name_Compilation_ISO_Date
| Name_Compilation_Date
| Name_Compilation_Time
then
Expand_Source_Info (N, Nam);
-- If we have a renaming, expand the call to the original operation,
-- which must itself be intrinsic, since renaming requires matching
-- conventions and this has already been checked.
elsif Present (Alias (E)) then
Expand_Intrinsic_Call (N, Alias (E));
elsif Nkind (N) in N_Binary_Op then
Expand_Binary_Operator_Call (N);
-- The only other case is where an external name was specified, since
-- this is the only way that an otherwise unrecognized name could
-- escape the checking in Sem_Prag. Nothing needs to be done in such
-- a case, since we pass such a call to the back end unchanged.
else
null;
end if;
end Expand_Intrinsic_Call;
------------------
-- Expand_Shift --
------------------
-- This procedure is used to convert a call to a shift function to the
-- corresponding operator node. This conversion is not done by the usual
-- circuit for converting calls to operator functions (e.g. "+"(1,2)) to
-- operator nodes, because shifts are not predefined operators.
-- As a result, whenever a shift is used in the source program, it will
-- remain as a call until converted by this routine to the operator node
-- form which the back end is expecting to see.
-- Note: it is possible for the expander to generate shift operator nodes
-- directly, which will be analyzed in the normal manner by calling Analyze
-- and Resolve. Such shift operator nodes will not be seen by Expand_Shift.
procedure Expand_Shift (N : Node_Id; E : Entity_Id; K : Node_Kind) is
Entyp : constant Entity_Id := Etype (E);
Left : constant Node_Id := First_Actual (N);
Loc : constant Source_Ptr := Sloc (N);
Right : constant Node_Id := Next_Actual (Left);
Ltyp : constant Node_Id := Etype (Left);
Rtyp : constant Node_Id := Etype (Right);
Typ : constant Entity_Id := Etype (N);
Snode : Node_Id;
begin
Snode := New_Node (K, Loc);
Set_Right_Opnd (Snode, Relocate_Node (Right));
Set_Chars (Snode, Chars (E));
Set_Etype (Snode, Base_Type (Entyp));
Set_Entity (Snode, E);
if Compile_Time_Known_Value (Type_High_Bound (Rtyp))
and then Expr_Value (Type_High_Bound (Rtyp)) < Esize (Ltyp)
then
Set_Shift_Count_OK (Snode, True);
end if;
if Typ = Entyp then
-- Note that we don't call Analyze and Resolve on this node, because
-- it already got analyzed and resolved when it was a function call.
Set_Left_Opnd (Snode, Relocate_Node (Left));
Rewrite (N, Snode);
Set_Analyzed (N);
-- However, we do call the expander, so that the expansion for
-- rotates and shift_right_arithmetic happens if Modify_Tree_For_C
-- is set.
if Expander_Active then
Expand (N);
end if;
else
-- If the context type is not the type of the operator, it is an
-- inherited operator for a derived type. Wrap the node in a
-- conversion so that it is type-consistent for possible further
-- expansion (e.g. within a lock-free protected type).
Set_Left_Opnd (Snode,
Unchecked_Convert_To (Base_Type (Entyp), Relocate_Node (Left)));
Rewrite (N, Unchecked_Convert_To (Typ, Snode));
-- Analyze and resolve result formed by conversion to target type
Analyze_And_Resolve (N, Typ);
end if;
end Expand_Shift;
------------------------
-- Expand_Source_Info --
------------------------
procedure Expand_Source_Info (N : Node_Id; Nam : Name_Id) is
Loc : constant Source_Ptr := Sloc (N);
begin
-- Integer cases
if Nam = Name_Line then
Rewrite (N,
Make_Integer_Literal (Loc,
Intval => UI_From_Int (Int (Get_Logical_Line_Number (Loc)))));
Analyze_And_Resolve (N, Standard_Positive);
-- String cases
else
declare
Buf : Bounded_String;
begin
Add_Source_Info (Buf, Loc, Nam);
Rewrite (N, Make_String_Literal (Loc, Strval => +Buf));
Analyze_And_Resolve (N, Standard_String);
end;
end if;
Set_Is_Static_Expression (N);
end Expand_Source_Info;
---------------------------
-- Expand_Unc_Conversion --
---------------------------
procedure Expand_Unc_Conversion (N : Node_Id; E : Entity_Id) is
Func : constant Entity_Id := Entity (Name (N));
Conv : Node_Id;
Ftyp : Entity_Id;
Ttyp : Entity_Id;
begin
-- Rewrite as unchecked conversion node. Note that we must convert
-- the operand to the formal type of the input parameter of the
-- function, so that the resulting N_Unchecked_Type_Conversion
-- call indicates the correct types for Gigi.
-- Right now, we only do this if a scalar type is involved. It is
-- not clear if it is needed in other cases. If we do attempt to
-- do the conversion unconditionally, it crashes 3411-018. To be
-- investigated further ???
Conv := Relocate_Node (First_Actual (N));
Ftyp := Etype (First_Formal (Func));
if Is_Scalar_Type (Ftyp) then
Conv := Convert_To (Ftyp, Conv);
Set_Parent (Conv, N);
Analyze_And_Resolve (Conv);
end if;
-- The instantiation of Unchecked_Conversion creates a wrapper package,
-- and the target type is declared as a subtype of the actual. Recover
-- the actual, which is the subtype indic. in the subtype declaration
-- for the target type. This is semantically correct, and avoids
-- anomalies with access subtypes. For entities, leave type as is.
-- We do the analysis here, because we do not want the compiler
-- to try to optimize or otherwise reorganize the unchecked
-- conversion node.
Ttyp := Etype (E);
if Is_Entity_Name (Conv) then
null;
elsif Nkind (Parent (Ttyp)) = N_Subtype_Declaration then
Ttyp := Entity (Subtype_Indication (Parent (Etype (E))));
elsif Is_Itype (Ttyp) then
Ttyp :=
Entity (Subtype_Indication (Associated_Node_For_Itype (Ttyp)));
else
raise Program_Error;
end if;
Rewrite (N, Unchecked_Convert_To (Ttyp, Conv));
Analyze_And_Resolve (N, Ttyp);
end Expand_Unc_Conversion;
-----------------------------
-- Expand_Unc_Deallocation --
-----------------------------
procedure Expand_Unc_Deallocation (N : Node_Id) is
Arg : constant Node_Id := First_Actual (N);
Loc : constant Source_Ptr := Sloc (N);
Typ : constant Entity_Id := Etype (Arg);
Desig_Typ : constant Entity_Id :=
Available_View (Designated_Type (Typ));
Needs_Fin : constant Boolean := Needs_Finalization (Desig_Typ);
Root_Typ : constant Entity_Id := Underlying_Type (Root_Type (Typ));
Pool : constant Entity_Id := Associated_Storage_Pool (Root_Typ);
Stmts : constant List_Id := New_List;
Arg_Known_Non_Null : constant Boolean := Known_Non_Null (N);
-- This captures whether we know the argument to be non-null so that
-- we can avoid the test. The reason that we need to capture this is
-- that we analyze some generated statements before properly attaching
-- them to the tree, and that can disturb current value settings.
Exceptions_OK : constant Boolean :=
not Restriction_Active (No_Exception_Propagation);
Abrt_Blk : Node_Id := Empty;
Abrt_Blk_Id : Entity_Id;
Abrt_HSS : Node_Id;
AUD : Entity_Id;
Fin_Blk : Node_Id;
Fin_Call : Node_Id;
Fin_Data : Finalization_Exception_Data;
Free_Arg : Node_Id;
Free_Nod : Node_Id;
Gen_Code : Node_Id;
Obj_Ref : Node_Id;
begin
-- Nothing to do if we know the argument is null
if Known_Null (N) then
return;
end if;
-- Processing for pointer to controlled types. Generate:
-- Abrt : constant Boolean := ...;
-- Ex : Exception_Occurrence;
-- Raised : Boolean := False;
-- begin
-- Abort_Defer;
-- begin
-- [Deep_]Finalize (Obj_Ref);
-- exception
-- when others =>
-- if not Raised then
-- Raised := True;
-- Save_Occurrence (Ex, Get_Current_Excep.all.all);
-- end;
-- at end
-- Abort_Undefer_Direct;
-- end;
-- Depending on whether exception propagation is enabled and/or aborts
-- are allowed, the generated code may lack block statements.
if Needs_Fin then
-- Ada 2005 (AI-251): In case of abstract interface type we displace
-- the pointer to reference the base of the object to deallocate its
-- memory, unless we're targetting a VM, in which case no special
-- processing is required.
if Is_Interface (Directly_Designated_Type (Typ))
and then Tagged_Type_Expansion
then
Obj_Ref :=
Make_Explicit_Dereference (Loc,
Prefix =>
Unchecked_Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Base_Address), Loc),
Parameter_Associations => New_List (
Unchecked_Convert_To (RTE (RE_Address),
Duplicate_Subexpr_No_Checks (Arg))))));
else
Obj_Ref :=
Make_Explicit_Dereference (Loc,
Prefix => Duplicate_Subexpr_No_Checks (Arg));
end if;
-- If the designated type is tagged, the finalization call must
-- dispatch because the designated type may not be the actual type
-- of the object. If the type is synchronized, the deallocation
-- applies to the corresponding record type.
if Is_Tagged_Type (Desig_Typ) then
if Is_Concurrent_Type (Desig_Typ) then
Obj_Ref :=
Unchecked_Convert_To
(Class_Wide_Type (Corresponding_Record_Type (Desig_Typ)),
Obj_Ref);
elsif not Is_Class_Wide_Type (Desig_Typ) then
Obj_Ref :=
Unchecked_Convert_To (Class_Wide_Type (Desig_Typ), Obj_Ref);
end if;
-- Otherwise the designated type is untagged. Set the type of the
-- dereference explicitly to force a conversion when needed given
-- that [Deep_]Finalize may be inherited from a parent type.
else
Set_Etype (Obj_Ref, Desig_Typ);
end if;
-- Generate:
-- [Deep_]Finalize (Obj_Ref);
Fin_Call := Make_Final_Call (Obj_Ref => Obj_Ref, Typ => Desig_Typ);
-- Generate:
-- Abrt : constant Boolean := ...;
-- Ex : Exception_Occurrence;
-- Raised : Boolean := False;
-- begin
-- <Fin_Call>
-- exception
-- when others =>
-- if not Raised then
-- Raised := True;
-- Save_Occurrence (Ex, Get_Current_Excep.all.all);
-- end;
if Exceptions_OK then
Build_Object_Declarations (Fin_Data, Stmts, Loc);
Fin_Blk :=
Make_Block_Statement (Loc,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (Fin_Call),
Exception_Handlers => New_List (
Build_Exception_Handler (Fin_Data))));
-- Otherwise exception propagation is not allowed
else
Fin_Blk := Fin_Call;
end if;
-- The finalization action must be protected by an abort defer and
-- undefer pair when aborts are allowed. Generate:
-- begin
-- Abort_Defer;
-- <Fin_Blk>
-- at end
-- Abort_Undefer_Direct;
-- end;
if Abort_Allowed then
AUD := RTE (RE_Abort_Undefer_Direct);
Abrt_HSS :=
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (
Build_Runtime_Call (Loc, RE_Abort_Defer),
Fin_Blk),
At_End_Proc => New_Occurrence_Of (AUD, Loc));
Abrt_Blk :=
Make_Block_Statement (Loc,
Handled_Statement_Sequence => Abrt_HSS);
Add_Block_Identifier (Abrt_Blk, Abrt_Blk_Id);
Expand_At_End_Handler (Abrt_HSS, Abrt_Blk_Id);
-- Present the Abort_Undefer_Direct function to the backend so
-- that it can inline the call to the function.
Add_Inlined_Body (AUD, N);
-- Otherwise aborts are not allowed
else
Abrt_Blk := Fin_Blk;
end if;
Append_To (Stmts, Abrt_Blk);
end if;
-- For a task type, call Free_Task before freeing the ATCB. We used to
-- detect the case of Abort followed by a Free here, because the Free
-- wouldn't actually free if it happens before the aborted task actually
-- terminates. The warning was removed, because Free now works properly
-- (the task will be freed once it terminates).
if Is_Task_Type (Desig_Typ) then
Append_To (Stmts,
Cleanup_Task (N, Duplicate_Subexpr_No_Checks (Arg)));
-- For composite types that contain tasks, recurse over the structure
-- to build the selectors for the task subcomponents.
elsif Has_Task (Desig_Typ) then
if Is_Array_Type (Desig_Typ) then
Append_List_To (Stmts, Cleanup_Array (N, Arg, Desig_Typ));
elsif Is_Record_Type (Desig_Typ) then
Append_List_To (Stmts, Cleanup_Record (N, Arg, Desig_Typ));
end if;
end if;
-- Same for simple protected types. Eventually call Finalize_Protection
-- before freeing the PO for each protected component.
if Is_Simple_Protected_Type (Desig_Typ) then
Append_To (Stmts,
Cleanup_Protected_Object (N, Duplicate_Subexpr_No_Checks (Arg)));
elsif Has_Simple_Protected_Object (Desig_Typ) then
if Is_Array_Type (Desig_Typ) then
Append_List_To (Stmts, Cleanup_Array (N, Arg, Desig_Typ));
elsif Is_Record_Type (Desig_Typ) then
Append_List_To (Stmts, Cleanup_Record (N, Arg, Desig_Typ));
end if;
end if;
-- Normal processing for non-controlled types. The argument to free is
-- a renaming rather than a constant to ensure that the original context
-- is always set to null after the deallocation takes place.
Free_Arg := Duplicate_Subexpr_No_Checks (Arg, Renaming_Req => True);
Free_Nod := Make_Free_Statement (Loc, Empty);
Append_To (Stmts, Free_Nod);
Set_Storage_Pool (Free_Nod, Pool);
-- Attach to tree before analysis of generated subtypes below
Set_Parent (Stmts, Parent (N));
-- Deal with storage pool
if Present (Pool) then
-- Freeing the secondary stack is meaningless
if Is_RTE (Pool, RE_SS_Pool) then
null;
-- If the pool object is of a simple storage pool type, then attempt
-- to locate the type's Deallocate procedure, if any, and set the
-- free operation's procedure to call. If the type doesn't have a
-- Deallocate (which is allowed), then the actual will simply be set
-- to null.
elsif Present
(Get_Rep_Pragma (Etype (Pool), Name_Simple_Storage_Pool_Type))
then
declare
Pool_Typ : constant Entity_Id := Base_Type (Etype (Pool));
Dealloc : Entity_Id;
begin
Dealloc := Get_Name_Entity_Id (Name_Deallocate);
while Present (Dealloc) loop
if Scope (Dealloc) = Scope (Pool_Typ)
and then Present (First_Formal (Dealloc))
and then Etype (First_Formal (Dealloc)) = Pool_Typ
then
Set_Procedure_To_Call (Free_Nod, Dealloc);
exit;
else
Dealloc := Homonym (Dealloc);
end if;
end loop;
end;
-- Case of a class-wide pool type: make a dispatching call to
-- Deallocate through the class-wide Deallocate_Any.
elsif Is_Class_Wide_Type (Etype (Pool)) then
Set_Procedure_To_Call (Free_Nod, RTE (RE_Deallocate_Any));
-- Case of a specific pool type: make a statically bound call
else
Set_Procedure_To_Call
(Free_Nod, Find_Storage_Op (Etype (Pool), Name_Deallocate));
end if;
end if;
if Present (Procedure_To_Call (Free_Nod)) then
-- For all cases of a Deallocate call, the back-end needs to be able
-- to compute the size of the object being freed. This may require
-- some adjustments for objects of dynamic size.
--
-- If the type is class wide, we generate an implicit type with the
-- right dynamic size, so that the deallocate call gets the right
-- size parameter computed by GIGI. Same for an access to
-- unconstrained packed array.
if Is_Class_Wide_Type (Desig_Typ)
or else
(Is_Packed_Array (Desig_Typ)
and then not Is_Constrained (Desig_Typ))
then
declare
Deref : constant Node_Id :=
Make_Explicit_Dereference (Loc,
Duplicate_Subexpr_No_Checks (Arg));
D_Subtyp : Node_Id;
D_Type : Entity_Id;
begin
-- Perform minor decoration as it is needed by the side effect
-- removal mechanism.
Set_Etype (Deref, Desig_Typ);
Set_Parent (Deref, Free_Nod);
D_Subtyp := Make_Subtype_From_Expr (Deref, Desig_Typ);
if Nkind (D_Subtyp) in N_Has_Entity then
D_Type := Entity (D_Subtyp);
else
D_Type := Make_Temporary (Loc, 'A');
Insert_Action (Deref,
Make_Subtype_Declaration (Loc,
Defining_Identifier => D_Type,
Subtype_Indication => D_Subtyp));
end if;
-- Force freezing at the point of the dereference. For the
-- class wide case, this avoids having the subtype frozen
-- before the equivalent type.
Freeze_Itype (D_Type, Deref);
Set_Actual_Designated_Subtype (Free_Nod, D_Type);
end;
end if;
end if;
-- Ada 2005 (AI-251): In case of abstract interface type we must
-- displace the pointer to reference the base of the object to
-- deallocate its memory, unless we're targetting a VM, in which case
-- no special processing is required.
-- Generate:
-- free (Base_Address (Obj_Ptr))
if Is_Interface (Directly_Designated_Type (Typ))
and then Tagged_Type_Expansion
then
Set_Expression (Free_Nod,
Unchecked_Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Base_Address), Loc),
Parameter_Associations => New_List (
Unchecked_Convert_To (RTE (RE_Address), Free_Arg)))));
-- Generate:
-- free (Obj_Ptr)
else
Set_Expression (Free_Nod, Free_Arg);
end if;
-- Only remaining step is to set result to null, or generate a raise of
-- Constraint_Error if the target object is "not null".
if Can_Never_Be_Null (Etype (Arg)) then
Append_To (Stmts,
Make_Raise_Constraint_Error (Loc,
Reason => CE_Access_Check_Failed));
else
declare
Lhs : constant Node_Id := Duplicate_Subexpr_No_Checks (Arg);
begin
Set_Assignment_OK (Lhs);
Append_To (Stmts,
Make_Assignment_Statement (Loc,
Name => Lhs,
Expression => Make_Null (Loc)));
end;
end if;
-- Generate a test of whether any earlier finalization raised an
-- exception, and in that case raise Program_Error with the previous
-- exception occurrence.
-- Generate:
-- if Raised and then not Abrt then
-- raise Program_Error; -- for restricted RTS
-- <or>
-- Raise_From_Controlled_Operation (E); -- all other cases
-- end if;
if Needs_Fin and then Exceptions_OK then
Append_To (Stmts, Build_Raise_Statement (Fin_Data));
end if;
-- If we know the argument is non-null, then make a block statement
-- that contains the required statements, no need for a test.
if Arg_Known_Non_Null then
Gen_Code :=
Make_Block_Statement (Loc,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Stmts));
-- If the argument may be null, wrap the statements inside an IF that
-- does an explicit test to exclude the null case.
else
Gen_Code :=
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Ne (Loc,
Left_Opnd => Duplicate_Subexpr (Arg),
Right_Opnd => Make_Null (Loc)),
Then_Statements => Stmts);
end if;
-- Rewrite the call
Rewrite (N, Gen_Code);
Analyze (N);
end Expand_Unc_Deallocation;
-----------------------
-- Expand_To_Address --
-----------------------
procedure Expand_To_Address (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Arg : constant Node_Id := First_Actual (N);
Obj : Node_Id;
begin
Remove_Side_Effects (Arg);
Obj := Make_Explicit_Dereference (Loc, Relocate_Node (Arg));
Rewrite (N,
Make_If_Expression (Loc,
Expressions => New_List (
Make_Op_Eq (Loc,
Left_Opnd => New_Copy_Tree (Arg),
Right_Opnd => Make_Null (Loc)),
New_Occurrence_Of (RTE (RE_Null_Address), Loc),
Make_Attribute_Reference (Loc,
Prefix => Obj,
Attribute_Name => Name_Address))));
Analyze_And_Resolve (N, RTE (RE_Address));
end Expand_To_Address;
-----------------------
-- Expand_To_Pointer --
-----------------------
procedure Expand_To_Pointer (N : Node_Id) is
Arg : constant Node_Id := First_Actual (N);
begin
Rewrite (N, Unchecked_Convert_To (Etype (N), Arg));
Analyze (N);
end Expand_To_Pointer;
end Exp_Intr;