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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- E X P _ A T 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 Aspects; use Aspects;
with Atree; use Atree;
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 Exp_Atag; use Exp_Atag;
with Exp_Ch3; use Exp_Ch3;
with Exp_Ch6; use Exp_Ch6;
with Exp_Ch9; use Exp_Ch9;
with Exp_Dist; use Exp_Dist;
with Exp_Imgv; use Exp_Imgv;
with Exp_Pakd; use Exp_Pakd;
with Exp_Strm; use Exp_Strm;
with Exp_Put_Image;
with Exp_Tss; use Exp_Tss;
with Exp_Util; use Exp_Util;
with Expander; use Expander;
with Freeze; use Freeze;
with Gnatvsn; use Gnatvsn;
with Itypes; use Itypes;
with Lib; use Lib;
with Namet; use Namet;
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_Ch6; use Sem_Ch6;
with Sem_Ch7; use Sem_Ch7;
with Sem_Ch8; use Sem_Ch8;
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 Stringt; use Stringt;
with Strub; use Strub;
with Tbuild; use Tbuild;
with Ttypes; use Ttypes;
with Uintp; use Uintp;
with Uname; use Uname;
with Urealp; use Urealp;
with Validsw; use Validsw;
package body Exp_Attr is
-----------------------
-- Local Subprograms --
-----------------------
function Build_Array_VS_Func
(Attr : Node_Id;
Formal_Typ : Entity_Id;
Array_Typ : Entity_Id) return Entity_Id;
-- Validate the components of an array type by means of a function. Return
-- the entity of the validation function. The parameters are as follows:
--
-- * Attr - the 'Valid_Scalars attribute for which the function is
-- generated.
--
-- * Formal_Typ - the type of the generated function's only formal
-- parameter.
--
-- * Array_Typ - the array type whose components are to be validated
function Build_Disp_Get_Task_Id_Call (Actual : Node_Id) return Node_Id;
-- Build a call to Disp_Get_Task_Id, passing Actual as actual parameter
function Build_Record_VS_Func
(Attr : Node_Id;
Formal_Typ : Entity_Id;
Rec_Typ : Entity_Id) return Entity_Id;
-- Validate the components, discriminants, and variants of a record type by
-- means of a function. Return the entity of the validation function. The
-- parameters are as follows:
--
-- * Attr - the 'Valid_Scalars attribute for which the function is
-- generated.
--
-- * Formal_Typ - the type of the generated function's only formal
-- parameter.
--
-- * Rec_Typ - the record type whose internals are to be validated
procedure Compile_Stream_Body_In_Scope
(N : Node_Id;
Decl : Node_Id;
Arr : Entity_Id);
-- The body for a stream subprogram may be generated outside of the scope
-- of the type. If the type is fully private, it may depend on the full
-- view of other types (e.g. indexes) that are currently private as well.
-- We install the declarations of the package in which the type is declared
-- before compiling the body in what is its proper environment. The Check
-- parameter indicates if checks are to be suppressed for the stream body.
-- We suppress checks for array/record reads, since the rule is that these
-- are like assignments, out of range values due to uninitialized storage,
-- or other invalid values do NOT cause a Constraint_Error to be raised.
-- If we are within an instance body all visibility has been established
-- already and there is no need to install the package.
-- This mechanism is now extended to the component types of the array type,
-- when the component type is not in scope and is private, to handle
-- properly the case when the full view has defaulted discriminants.
-- This special processing is ultimately caused by the fact that the
-- compiler lacks a well-defined phase when full views are visible
-- everywhere. Having such a separate pass would remove much of the
-- special-case code that shuffles partial and full views in the middle
-- of semantic analysis and expansion.
function Default_Streaming_Unavailable (Typ : Entity_Id) return Boolean;
--
-- In most cases, references to unavailable streaming attributes
-- are rejected at compile time. In some obscure cases involving
-- generics and formal derived types, the problem is dealt with at runtime.
procedure Expand_Access_To_Protected_Op
(N : Node_Id;
Pref : Node_Id;
Typ : Entity_Id);
-- An attribute reference to a protected subprogram is transformed into
-- a pair of pointers: one to the object, and one to the operations.
-- This expansion is performed for 'Access and for 'Unrestricted_Access.
procedure Expand_Fpt_Attribute
(N : Node_Id;
Pkg : RE_Id;
Nam : Name_Id;
Args : List_Id);
-- This procedure expands a call to a floating-point attribute function.
-- N is the attribute reference node, and Args is a list of arguments to
-- be passed to the function call. Pkg identifies the package containing
-- the appropriate instantiation of System.Fat_Gen. Float arguments in Args
-- have already been converted to the floating-point type for which Pkg was
-- instantiated. The Nam argument is the relevant attribute processing
-- routine to be called. This is the same as the attribute name.
procedure Expand_Fpt_Attribute_R (N : Node_Id);
-- This procedure expands a call to a floating-point attribute function
-- that takes a single floating-point argument. The function to be called
-- is always the same as the attribute name.
procedure Expand_Fpt_Attribute_RI (N : Node_Id);
-- This procedure expands a call to a floating-point attribute function
-- that takes one floating-point argument and one integer argument. The
-- function to be called is always the same as the attribute name.
procedure Expand_Fpt_Attribute_RR (N : Node_Id);
-- This procedure expands a call to a floating-point attribute function
-- that takes two floating-point arguments. The function to be called
-- is always the same as the attribute name.
procedure Expand_Loop_Entry_Attribute (N : Node_Id);
-- Handle the expansion of attribute 'Loop_Entry. As a result, the related
-- loop may be converted into a conditional block. See body for details.
procedure Expand_Min_Max_Attribute (N : Node_Id);
-- Handle the expansion of attributes 'Max and 'Min, including expanding
-- then out if we are in Modify_Tree_For_C mode.
procedure Expand_Pred_Succ_Attribute (N : Node_Id);
-- Handles expansion of Pred or Succ attributes for case of non-real
-- operand with overflow checking required.
procedure Expand_Update_Attribute (N : Node_Id);
-- Handle the expansion of attribute Update
procedure Find_Fat_Info
(T : Entity_Id;
Fat_Type : out Entity_Id;
Fat_Pkg : out RE_Id);
-- Given a floating-point type T, identifies the package containing the
-- attributes for this type (returned in Fat_Pkg), and the corresponding
-- type for which this package was instantiated from Fat_Gen. Error if T
-- is not a floating-point type.
function Find_Stream_Subprogram
(Typ : Entity_Id;
Nam : TSS_Name_Type) return Entity_Id;
-- Returns the stream-oriented subprogram attribute for Typ. For tagged
-- types, the corresponding primitive operation is looked up, else the
-- appropriate TSS from the type itself, or from its closest ancestor
-- defining it, is returned. In both cases, inheritance of representation
-- aspects is thus taken into account.
function Full_Base (T : Entity_Id) return Entity_Id;
-- The stream functions need to examine the underlying representation of
-- composite types. In some cases T may be non-private but its base type
-- is, in which case the function returns the corresponding full view.
function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id;
-- Given a type, find a corresponding stream convert pragma that applies to
-- the implementation base type of this type (Typ). If found, return the
-- pragma node, otherwise return Empty if no pragma is found.
function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean;
-- Utility for array attributes, returns true on packed constrained
-- arrays, and on access to same.
function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean;
-- Returns true iff the given node refers to an attribute call that
-- can be expanded directly by the back end and does not need front end
-- expansion. Typically used for rounding and truncation attributes that
-- appear directly inside a conversion to integer.
-------------------------
-- Build_Array_VS_Func --
-------------------------
function Build_Array_VS_Func
(Attr : Node_Id;
Formal_Typ : Entity_Id;
Array_Typ : Entity_Id) return Entity_Id
is
Loc : constant Source_Ptr := Sloc (Attr);
Comp_Typ : constant Entity_Id :=
Validated_View (Component_Type (Array_Typ));
function Validate_Component
(Obj_Id : Entity_Id;
Indexes : List_Id) return Node_Id;
-- Process a single component denoted by indexes Indexes. Obj_Id denotes
-- the entity of the validation parameter. Return the check associated
-- with the component.
function Validate_Dimension
(Obj_Id : Entity_Id;
Dim : Int;
Indexes : List_Id) return Node_Id;
-- Process dimension Dim of the array type. Obj_Id denotes the entity
-- of the validation parameter. Indexes is a list where each dimension
-- deposits its loop variable, which will later identify a component.
-- Return the loop associated with the current dimension.
------------------------
-- Validate_Component --
------------------------
function Validate_Component
(Obj_Id : Entity_Id;
Indexes : List_Id) return Node_Id
is
Attr_Nam : Name_Id;
begin
if Is_Scalar_Type (Comp_Typ) then
Attr_Nam := Name_Valid;
else
Attr_Nam := Name_Valid_Scalars;
end if;
-- Generate:
-- if not Array_Typ (Obj_Id) (Indexes)'Valid[_Scalars] then
-- return False;
-- end if;
return
Make_If_Statement (Loc,
Condition =>
Make_Op_Not (Loc,
Right_Opnd =>
Make_Attribute_Reference (Loc,
Prefix =>
Make_Indexed_Component (Loc,
Prefix =>
Unchecked_Convert_To (Array_Typ,
New_Occurrence_Of (Obj_Id, Loc)),
Expressions => Indexes),
Attribute_Name => Attr_Nam)),
Then_Statements => New_List (
Make_Simple_Return_Statement (Loc,
Expression => New_Occurrence_Of (Standard_False, Loc))));
end Validate_Component;
------------------------
-- Validate_Dimension --
------------------------
function Validate_Dimension
(Obj_Id : Entity_Id;
Dim : Int;
Indexes : List_Id) return Node_Id
is
Index : Entity_Id;
begin
-- Validate the component once all dimensions have produced their
-- individual loops.
if Dim > Number_Dimensions (Array_Typ) then
return Validate_Component (Obj_Id, Indexes);
-- Process the current dimension
else
Index :=
Make_Defining_Identifier (Loc, New_External_Name ('J', Dim));
Append_To (Indexes, New_Occurrence_Of (Index, Loc));
-- Generate:
-- for J1 in Array_Typ (Obj_Id)'Range (1) loop
-- for JN in Array_Typ (Obj_Id)'Range (N) loop
-- if not Array_Typ (Obj_Id) (Indexes)'Valid[_Scalars]
-- then
-- return False;
-- end if;
-- end loop;
-- end loop;
return
Make_Implicit_Loop_Statement (Attr,
Identifier => Empty,
Iteration_Scheme =>
Make_Iteration_Scheme (Loc,
Loop_Parameter_Specification =>
Make_Loop_Parameter_Specification (Loc,
Defining_Identifier => Index,
Discrete_Subtype_Definition =>
Make_Attribute_Reference (Loc,
Prefix =>
Unchecked_Convert_To (Array_Typ,
New_Occurrence_Of (Obj_Id, Loc)),
Attribute_Name => Name_Range,
Expressions => New_List (
Make_Integer_Literal (Loc, Dim))))),
Statements => New_List (
Validate_Dimension (Obj_Id, Dim + 1, Indexes)));
end if;
end Validate_Dimension;
-- Local variables
Func_Id : constant Entity_Id := Make_Temporary (Loc, 'V');
Indexes : constant List_Id := New_List;
Obj_Id : constant Entity_Id := Make_Temporary (Loc, 'A');
Stmts : List_Id;
-- Start of processing for Build_Array_VS_Func
begin
Stmts := New_List (Validate_Dimension (Obj_Id, 1, Indexes));
-- Generate:
-- return True;
Append_To (Stmts,
Make_Simple_Return_Statement (Loc,
Expression => New_Occurrence_Of (Standard_True, Loc)));
-- Generate:
-- function Func_Id (Obj_Id : Formal_Typ) return Boolean is
-- begin
-- Stmts
-- end Func_Id;
Mutate_Ekind (Func_Id, E_Function);
Set_Is_Internal (Func_Id);
Set_Is_Pure (Func_Id);
if not Debug_Generated_Code then
Set_Debug_Info_Off (Func_Id);
end if;
Insert_Action (Attr,
Make_Subprogram_Body (Loc,
Specification =>
Make_Function_Specification (Loc,
Defining_Unit_Name => Func_Id,
Parameter_Specifications => New_List (
Make_Parameter_Specification (Loc,
Defining_Identifier => Obj_Id,
Parameter_Type => New_Occurrence_Of (Formal_Typ, Loc))),
Result_Definition =>
New_Occurrence_Of (Standard_Boolean, Loc)),
Declarations => New_List,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Stmts)));
return Func_Id;
end Build_Array_VS_Func;
---------------------------------
-- Build_Disp_Get_Task_Id_Call --
---------------------------------
function Build_Disp_Get_Task_Id_Call (Actual : Node_Id) return Node_Id is
Loc : constant Source_Ptr := Sloc (Actual);
Typ : constant Entity_Id := Etype (Actual);
Subp : constant Entity_Id := Find_Prim_Op (Typ, Name_uDisp_Get_Task_Id);
begin
-- Generate:
-- _Disp_Get_Task_Id (Actual)
return
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Subp, Loc),
Parameter_Associations => New_List (Actual));
end Build_Disp_Get_Task_Id_Call;
--------------------------
-- Build_Record_VS_Func --
--------------------------
function Build_Record_VS_Func
(Attr : Node_Id;
Formal_Typ : Entity_Id;
Rec_Typ : Entity_Id) return Entity_Id
is
-- NOTE: The logic of Build_Record_VS_Func is intentionally passive.
-- It generates code only when there are components, discriminants,
-- or variant parts to validate.
-- NOTE: The routines within Build_Record_VS_Func are intentionally
-- unnested to avoid deep indentation of code.
Loc : constant Source_Ptr := Sloc (Attr);
procedure Validate_Component_List
(Obj_Id : Entity_Id;
Comp_List : Node_Id;
Stmts : in out List_Id);
-- Process all components and variant parts of component list Comp_List.
-- Obj_Id denotes the entity of the validation parameter. All new code
-- is added to list Stmts.
procedure Validate_Field
(Obj_Id : Entity_Id;
Field : Node_Id;
Cond : in out Node_Id);
-- Process component declaration or discriminant specification Field.
-- Obj_Id denotes the entity of the validation parameter. Cond denotes
-- an "or else" conditional expression which contains the new code (if
-- any).
procedure Validate_Fields
(Obj_Id : Entity_Id;
Fields : List_Id;
Stmts : in out List_Id);
-- Process component declarations or discriminant specifications in list
-- Fields. Obj_Id denotes the entity of the validation parameter. All
-- new code is added to list Stmts.
procedure Validate_Variant
(Obj_Id : Entity_Id;
Var : Node_Id;
Alts : in out List_Id);
-- Process variant Var. Obj_Id denotes the entity of the validation
-- parameter. Alts denotes a list of case statement alternatives which
-- contains the new code (if any).
procedure Validate_Variant_Part
(Obj_Id : Entity_Id;
Var_Part : Node_Id;
Stmts : in out List_Id);
-- Process variant part Var_Part. Obj_Id denotes the entity of the
-- validation parameter. All new code is added to list Stmts.
-----------------------------
-- Validate_Component_List --
-----------------------------
procedure Validate_Component_List
(Obj_Id : Entity_Id;
Comp_List : Node_Id;
Stmts : in out List_Id)
is
Var_Part : constant Node_Id := Variant_Part (Comp_List);
begin
-- Validate all components
Validate_Fields
(Obj_Id => Obj_Id,
Fields => Component_Items (Comp_List),
Stmts => Stmts);
-- Validate the variant part
if Present (Var_Part) then
Validate_Variant_Part
(Obj_Id => Obj_Id,
Var_Part => Var_Part,
Stmts => Stmts);
end if;
end Validate_Component_List;
--------------------
-- Validate_Field --
--------------------
procedure Validate_Field
(Obj_Id : Entity_Id;
Field : Node_Id;
Cond : in out Node_Id)
is
Field_Id : constant Entity_Id := Defining_Entity (Field);
Field_Nam : constant Name_Id := Chars (Field_Id);
Field_Typ : constant Entity_Id := Validated_View (Etype (Field_Id));
Attr_Nam : Name_Id;
begin
-- Do not process internally-generated fields. Note that checking for
-- Comes_From_Source is not correct because this will eliminate the
-- components within the corresponding record of a protected type.
if Field_Nam in Name_uObject | Name_uParent | Name_uTag then
null;
-- Do not process fields without any scalar components
elsif not Scalar_Part_Present (Field_Typ) then
null;
-- Otherwise the field needs to be validated. Use Make_Identifier
-- rather than New_Occurrence_Of to identify the field because the
-- wrong entity may be picked up when private types are involved.
-- Generate:
-- [or else] not Rec_Typ (Obj_Id).Item_Nam'Valid[_Scalars]
else
if Is_Scalar_Type (Field_Typ) then
Attr_Nam := Name_Valid;
else
Attr_Nam := Name_Valid_Scalars;
end if;
Evolve_Or_Else (Cond,
Make_Op_Not (Loc,
Right_Opnd =>
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix =>
Unchecked_Convert_To (Rec_Typ,
New_Occurrence_Of (Obj_Id, Loc)),
Selector_Name => Make_Identifier (Loc, Field_Nam)),
Attribute_Name => Attr_Nam)));
end if;
end Validate_Field;
---------------------
-- Validate_Fields --
---------------------
procedure Validate_Fields
(Obj_Id : Entity_Id;
Fields : List_Id;
Stmts : in out List_Id)
is
Cond : Node_Id;
Field : Node_Id;
begin
-- Assume that none of the fields are eligible for verification
Cond := Empty;
-- Validate all fields
Field := First_Non_Pragma (Fields);
while Present (Field) loop
Validate_Field
(Obj_Id => Obj_Id,
Field => Field,
Cond => Cond);
Next_Non_Pragma (Field);
end loop;
-- Generate:
-- if not Rec_Typ (Obj_Id).Item_Nam_1'Valid[_Scalars]
-- or else not Rec_Typ (Obj_Id).Item_Nam_N'Valid[_Scalars]
-- then
-- return False;
-- end if;
if Present (Cond) then
Append_New_To (Stmts,
Make_Implicit_If_Statement (Attr,
Condition => Cond,
Then_Statements => New_List (
Make_Simple_Return_Statement (Loc,
Expression => New_Occurrence_Of (Standard_False, Loc)))));
end if;
end Validate_Fields;
----------------------
-- Validate_Variant --
----------------------
procedure Validate_Variant
(Obj_Id : Entity_Id;
Var : Node_Id;
Alts : in out List_Id)
is
Stmts : List_Id;
begin
-- Assume that none of the components and variants are eligible for
-- verification.
Stmts := No_List;
-- Validate components
Validate_Component_List
(Obj_Id => Obj_Id,
Comp_List => Component_List (Var),
Stmts => Stmts);
-- Generate a null statement in case none of the components were
-- verified because this will otherwise eliminate an alternative
-- from the variant case statement and render the generated code
-- illegal.
if No (Stmts) then
Append_New_To (Stmts, Make_Null_Statement (Loc));
end if;
-- Generate:
-- when Discrete_Choices =>
-- Stmts
Append_New_To (Alts,
Make_Case_Statement_Alternative (Loc,
Discrete_Choices =>
New_Copy_List_Tree (Discrete_Choices (Var)),
Statements => Stmts));
end Validate_Variant;
---------------------------
-- Validate_Variant_Part --
---------------------------
procedure Validate_Variant_Part
(Obj_Id : Entity_Id;
Var_Part : Node_Id;
Stmts : in out List_Id)
is
Vars : constant List_Id := Variants (Var_Part);
Alts : List_Id;
Var : Node_Id;
begin
-- Assume that none of the variants are eligible for verification
Alts := No_List;
-- Validate variants
Var := First_Non_Pragma (Vars);
while Present (Var) loop
Validate_Variant
(Obj_Id => Obj_Id,
Var => Var,
Alts => Alts);
Next_Non_Pragma (Var);
end loop;
-- Even though individual variants may lack eligible components, the
-- alternatives must still be generated.
pragma Assert (Present (Alts));
-- Generate:
-- case Rec_Typ (Obj_Id).Discriminant is
-- when Discrete_Choices_1 =>
-- Stmts_1
-- when Discrete_Choices_N =>
-- Stmts_N
-- end case;
Append_New_To (Stmts,
Make_Case_Statement (Loc,
Expression =>
Make_Selected_Component (Loc,
Prefix =>
Unchecked_Convert_To (Rec_Typ,
New_Occurrence_Of (Obj_Id, Loc)),
Selector_Name => New_Copy_Tree (Name (Var_Part))),
Alternatives => Alts));
end Validate_Variant_Part;
-- Local variables
Func_Id : constant Entity_Id := Make_Temporary (Loc, 'V');
Obj_Id : constant Entity_Id := Make_Temporary (Loc, 'R');
Comps : Node_Id;
Stmts : List_Id;
Typ : Entity_Id;
Typ_Decl : Node_Id;
Typ_Def : Node_Id;
Typ_Ext : Node_Id;
-- Start of processing for Build_Record_VS_Func
begin
Typ := Validated_View (Rec_Typ);
-- Use the root type when dealing with a class-wide type
if Is_Class_Wide_Type (Typ) then
Typ := Validated_View (Root_Type (Typ));
end if;
Typ_Decl := Declaration_Node (Typ);
Typ_Def := Type_Definition (Typ_Decl);
-- The components of a derived type are located in the extension part
if Nkind (Typ_Def) = N_Derived_Type_Definition then
Typ_Ext := Record_Extension_Part (Typ_Def);
if Present (Typ_Ext) then
Comps := Component_List (Typ_Ext);
else
Comps := Empty;
end if;
-- Otherwise the components are available in the definition
else
Comps := Component_List (Typ_Def);
end if;
-- The code generated by this routine is as follows:
--
-- function Func_Id (Obj_Id : Formal_Typ) return Boolean is
-- begin
-- if not Rec_Typ (Obj_Id).Discriminant_1'Valid[_Scalars]
-- or else not Rec_Typ (Obj_Id).Discriminant_N'Valid[_Scalars]
-- then
-- return False;
-- end if;
--
-- if not Rec_Typ (Obj_Id).Component_1'Valid[_Scalars]
-- or else not Rec_Typ (Obj_Id).Component_N'Valid[_Scalars]
-- then
-- return False;
-- end if;
--
-- case Discriminant_1 is
-- when Choice_1 =>
-- if not Rec_Typ (Obj_Id).Component_1'Valid[_Scalars]
-- or else not Rec_Typ (Obj_Id).Component_N'Valid[_Scalars]
-- then
-- return False;
-- end if;
--
-- case Discriminant_N is
-- ...
-- when Choice_N =>
-- ...
-- end case;
--
-- return True;
-- end Func_Id;
-- Assume that the record type lacks eligible components, discriminants,
-- and variant parts.
Stmts := No_List;
-- Validate the discriminants
if not Is_Unchecked_Union (Rec_Typ) then
Validate_Fields
(Obj_Id => Obj_Id,
Fields => Discriminant_Specifications (Typ_Decl),
Stmts => Stmts);
end if;
-- Validate the components and variant parts
Validate_Component_List
(Obj_Id => Obj_Id,
Comp_List => Comps,
Stmts => Stmts);
-- Generate:
-- return True;
Append_New_To (Stmts,
Make_Simple_Return_Statement (Loc,
Expression => New_Occurrence_Of (Standard_True, Loc)));
-- Generate:
-- function Func_Id (Obj_Id : Formal_Typ) return Boolean is
-- begin
-- Stmts
-- end Func_Id;
Mutate_Ekind (Func_Id, E_Function);
Set_Is_Internal (Func_Id);
Set_Is_Pure (Func_Id);
if not Debug_Generated_Code then
Set_Debug_Info_Off (Func_Id);
end if;
Insert_Action (Attr,
Make_Subprogram_Body (Loc,
Specification =>
Make_Function_Specification (Loc,
Defining_Unit_Name => Func_Id,
Parameter_Specifications => New_List (
Make_Parameter_Specification (Loc,
Defining_Identifier => Obj_Id,
Parameter_Type => New_Occurrence_Of (Formal_Typ, Loc))),
Result_Definition =>
New_Occurrence_Of (Standard_Boolean, Loc)),
Declarations => New_List,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Stmts)),
Suppress => Discriminant_Check);
return Func_Id;
end Build_Record_VS_Func;
----------------------------------
-- Compile_Stream_Body_In_Scope --
----------------------------------
procedure Compile_Stream_Body_In_Scope
(N : Node_Id;
Decl : Node_Id;
Arr : Entity_Id)
is
C_Type : constant Entity_Id := Base_Type (Component_Type (Arr));
Curr : constant Entity_Id := Current_Scope;
Install : Boolean := False;
Scop : Entity_Id := Scope (Arr);
begin
if Is_Hidden (Arr)
and then not In_Open_Scopes (Scop)
and then Ekind (Scop) = E_Package
then
Install := True;
else
-- The component type may be private, in which case we install its
-- full view to compile the subprogram.
-- The component type may be private, in which case we install its
-- full view to compile the subprogram. We do not do this if the
-- type has a Stream_Convert pragma, which indicates that there are
-- special stream-processing operations for that type (for example
-- Unbounded_String and its wide varieties).
Scop := Scope (C_Type);
if Is_Private_Type (C_Type)
and then Present (Full_View (C_Type))
and then not In_Open_Scopes (Scop)
and then Ekind (Scop) = E_Package
and then No (Get_Stream_Convert_Pragma (C_Type))
then
Install := True;
end if;
end if;
-- If we are within an instance body, then all visibility has been
-- established already and there is no need to install the package.
if Install and then not In_Instance_Body then
Push_Scope (Scop);
Install_Visible_Declarations (Scop);
Install_Private_Declarations (Scop);
-- The entities in the package are now visible, but the generated
-- stream entity must appear in the current scope (usually an
-- enclosing stream function) so that itypes all have their proper
-- scopes.
Push_Scope (Curr);
else
Install := False;
end if;
Insert_Action (N, Decl);
if Install then
-- Remove extra copy of current scope, and package itself
Pop_Scope;
End_Package_Scope (Scop);
end if;
end Compile_Stream_Body_In_Scope;
-----------------------------------
-- Default_Streaming_Unavailable --
-----------------------------------
function Default_Streaming_Unavailable (Typ : Entity_Id) return Boolean is
Btyp : constant Entity_Id := Implementation_Base_Type (Typ);
begin
if Is_Immutably_Limited_Type (Btyp)
and then not Is_Tagged_Type (Btyp)
and then not (Ekind (Btyp) = E_Record_Type
and then Present (Corresponding_Concurrent_Type (Btyp)))
then
pragma Assert (In_Instance_Body);
return True;
end if;
return False;
end Default_Streaming_Unavailable;
-----------------------------------
-- Expand_Access_To_Protected_Op --
-----------------------------------
procedure Expand_Access_To_Protected_Op
(N : Node_Id;
Pref : Node_Id;
Typ : Entity_Id)
is
-- The value of the attribute_reference is a record containing two
-- fields: an access to the protected object, and an access to the
-- subprogram itself. The prefix is an identifier or a selected
-- component.
function Has_By_Protected_Procedure_Prefixed_View return Boolean;
-- Determine whether Pref denotes the prefixed class-wide interface
-- view of a procedure with synchronization kind By_Protected_Procedure.
----------------------------------------------
-- Has_By_Protected_Procedure_Prefixed_View --
----------------------------------------------
function Has_By_Protected_Procedure_Prefixed_View return Boolean is
begin
return Nkind (Pref) = N_Selected_Component
and then Nkind (Prefix (Pref)) in N_Has_Entity
and then Present (Entity (Prefix (Pref)))
and then Is_Class_Wide_Type (Etype (Entity (Prefix (Pref))))
and then (Is_Synchronized_Interface (Etype (Entity (Prefix (Pref))))
or else
Is_Protected_Interface (Etype (Entity (Prefix (Pref)))))
and then Is_By_Protected_Procedure (Entity (Selector_Name (Pref)));
end Has_By_Protected_Procedure_Prefixed_View;
-- Local variables
Loc : constant Source_Ptr := Sloc (N);
Agg : Node_Id;
Btyp : constant Entity_Id := Base_Type (Typ);
Sub : Entity_Id := Empty;
Sub_Ref : Node_Id;
E_T : constant Entity_Id := Equivalent_Type (Btyp);
Acc : constant Entity_Id :=
Etype (Next_Component (First_Component (E_T)));
Obj_Ref : Node_Id;
Curr : Entity_Id;
-- Start of processing for Expand_Access_To_Protected_Op
begin
-- Within the body of the protected type, the prefix designates a local
-- operation, and the object is the first parameter of the corresponding
-- protected body of the current enclosing operation.
if Is_Entity_Name (Pref) then
-- All indirect calls are external calls, so must do locking and
-- barrier reevaluation, even if the 'Access occurs within the
-- protected body. Hence the call to External_Subprogram, as opposed
-- to Protected_Body_Subprogram, below. See RM-9.5(5). This means
-- that indirect calls from within the same protected body will
-- deadlock, as allowed by RM-9.5.1(8,15,17).
Sub := New_Occurrence_Of (External_Subprogram (Entity (Pref)), Loc);
-- Don't traverse the scopes when the attribute occurs within an init
-- proc, because we directly use the _init formal of the init proc in
-- that case.
Curr := Current_Scope;
if not Is_Init_Proc (Curr) then
pragma Assert (In_Open_Scopes (Scope (Entity (Pref))));
while Scope (Curr) /= Scope (Entity (Pref)) loop
Curr := Scope (Curr);
end loop;
end if;
-- In case of protected entries the first formal of its Protected_
-- Body_Subprogram is the address of the object.
if Ekind (Curr) = E_Entry then
Obj_Ref :=
New_Occurrence_Of
(First_Formal
(Protected_Body_Subprogram (Curr)), Loc);
-- If the current scope is an init proc, then use the address of the
-- _init formal as the object reference.
elsif Is_Init_Proc (Curr) then
Obj_Ref :=
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (First_Formal (Curr), Loc),
Attribute_Name => Name_Address);
-- In case of protected subprograms the first formal of its
-- Protected_Body_Subprogram is the object and we get its address.
else
Obj_Ref :=
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of
(First_Formal
(Protected_Body_Subprogram (Curr)), Loc),
Attribute_Name => Name_Address);
end if;
elsif Has_By_Protected_Procedure_Prefixed_View then
Obj_Ref :=
Make_Attribute_Reference (Loc,
Prefix => Relocate_Node (Prefix (Pref)),
Attribute_Name => Name_Address);
-- Analyze the object address with expansion disabled. Required
-- because its expansion would displace the pointer to the object,
-- which is not correct at this stage since the object type is a
-- class-wide interface type and we are dispatching a call to a
-- thunk (which would erroneously displace the pointer again).
Expander_Mode_Save_And_Set (False);
Analyze (Obj_Ref);
Set_Analyzed (Obj_Ref);
Expander_Mode_Restore;
-- Case where the prefix is not an entity name. Find the
-- version of the protected operation to be called from
-- outside the protected object.
else
Sub :=
New_Occurrence_Of
(External_Subprogram
(Entity (Selector_Name (Pref))), Loc);
Obj_Ref :=
Make_Attribute_Reference (Loc,
Prefix => Relocate_Node (Prefix (Pref)),
Attribute_Name => Name_Address);
end if;
if Has_By_Protected_Procedure_Prefixed_View then
declare
Ctrl_Tag : Node_Id := Duplicate_Subexpr (Prefix (Pref));
Prim_Addr : Node_Id;
Subp : constant Entity_Id := Entity (Selector_Name (Pref));
Typ : constant Entity_Id :=
Etype (Etype (Entity (Prefix (Pref))));
begin
-- The target subprogram is a thunk; retrieve its address from
-- its secondary dispatch table slot.
Build_Get_Prim_Op_Address (Loc,
Typ => Typ,
Tag_Node => Ctrl_Tag,
Position => DT_Position (Subp),
New_Node => Prim_Addr);
-- Mark the access to the target subprogram as an access to the
-- dispatch table and perform an unchecked type conversion to such
-- access type. This is required to allow the backend to properly
-- identify and handle the access to the dispatch table slot on
-- targets where the dispatch table contains descriptors (instead
-- of pointers).
Set_Is_Dispatch_Table_Entity (Acc);
Sub_Ref := Unchecked_Convert_To (Acc, Prim_Addr);
Analyze (Sub_Ref);
Agg :=
Make_Aggregate (Loc,
Expressions => New_List (Obj_Ref, Sub_Ref));
end;
-- Common case
else
Sub_Ref :=
Make_Attribute_Reference (Loc,
Prefix => Sub,
Attribute_Name => Name_Access);
-- We set the type of the access reference to the already generated
-- access_to_subprogram type, and declare the reference analyzed,
-- to prevent further expansion when the enclosing aggregate is
-- analyzed.
Set_Etype (Sub_Ref, Acc);
Set_Analyzed (Sub_Ref);
Agg :=
Make_Aggregate (Loc,
Expressions => New_List (Obj_Ref, Sub_Ref));
-- Sub_Ref has been marked as analyzed, but we still need to make
-- sure Sub is correctly frozen.
Freeze_Before (N, Entity (Sub));
end if;
Rewrite (N, Agg);
Analyze_And_Resolve (N, E_T);
-- For subsequent analysis, the node must retain its type. The backend
-- will replace it with the equivalent type where needed.
Set_Etype (N, Typ);
end Expand_Access_To_Protected_Op;
--------------------------
-- Expand_Fpt_Attribute --
--------------------------
procedure Expand_Fpt_Attribute
(N : Node_Id;
Pkg : RE_Id;
Nam : Name_Id;
Args : List_Id)
is
Loc : constant Source_Ptr := Sloc (N);
Typ : constant Entity_Id := Etype (N);
Fnm : Node_Id;
begin
-- The function name is the selected component Attr_xxx.yyy where
-- Attr_xxx is the package name, and yyy is the argument Nam.
-- Note: it would be more usual to have separate RE entries for each
-- of the entities in the Fat packages, but first they have identical
-- names (so we would have to have lots of renaming declarations to
-- meet the normal RE rule of separate names for all runtime entities),
-- and second there would be an awful lot of them.
Fnm :=
Make_Selected_Component (Loc,
Prefix => New_Occurrence_Of (RTE (Pkg), Loc),
Selector_Name => Make_Identifier (Loc, Nam));
-- The generated call is given the provided set of parameters, and then
-- wrapped in a conversion which converts the result to the target type.
Rewrite (N,
Convert_To (Typ,
Make_Function_Call (Loc,
Name => Fnm,
Parameter_Associations => Args)));
Analyze_And_Resolve (N, Typ);
end Expand_Fpt_Attribute;
----------------------------
-- Expand_Fpt_Attribute_R --
----------------------------
-- The single argument is converted to its root type to call the
-- appropriate runtime function, with the actual call being built
-- by Expand_Fpt_Attribute
procedure Expand_Fpt_Attribute_R (N : Node_Id) is
E1 : constant Node_Id := First (Expressions (N));
Ftp : Entity_Id;
Pkg : RE_Id;
begin
Find_Fat_Info (Etype (E1), Ftp, Pkg);
Expand_Fpt_Attribute
(N, Pkg, Attribute_Name (N),
New_List (Unchecked_Convert_To (Ftp, Relocate_Node (E1))));
end Expand_Fpt_Attribute_R;
-----------------------------
-- Expand_Fpt_Attribute_RI --
-----------------------------
-- The first argument is converted to its root type and the second
-- argument is converted to standard long long integer to call the
-- appropriate runtime function, with the actual call being built
-- by Expand_Fpt_Attribute
procedure Expand_Fpt_Attribute_RI (N : Node_Id) is
E1 : constant Node_Id := First (Expressions (N));
E2 : constant Node_Id := Next (E1);
Ftp : Entity_Id;
Pkg : RE_Id;
begin
Find_Fat_Info (Etype (E1), Ftp, Pkg);
Expand_Fpt_Attribute
(N, Pkg, Attribute_Name (N),
New_List (
Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2))));
end Expand_Fpt_Attribute_RI;
-----------------------------
-- Expand_Fpt_Attribute_RR --
-----------------------------
-- The two arguments are converted to their root types to call the
-- appropriate runtime function, with the actual call being built
-- by Expand_Fpt_Attribute
procedure Expand_Fpt_Attribute_RR (N : Node_Id) is
E1 : constant Node_Id := First (Expressions (N));
E2 : constant Node_Id := Next (E1);
Ftp : Entity_Id;
Pkg : RE_Id;
begin
Find_Fat_Info (Etype (E1), Ftp, Pkg);
Expand_Fpt_Attribute
(N, Pkg, Attribute_Name (N),
New_List (
Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
Unchecked_Convert_To (Ftp, Relocate_Node (E2))));
end Expand_Fpt_Attribute_RR;
---------------------------------
-- Expand_Loop_Entry_Attribute --
---------------------------------
procedure Expand_Loop_Entry_Attribute (N : Node_Id) is
procedure Build_Conditional_Block
(Loc : Source_Ptr;
Cond : Node_Id;
Loop_Stmt : Node_Id;
If_Stmt : out Node_Id;
Blk_Stmt : out Node_Id);
-- Create a block Blk_Stmt with an empty declarative list and a single
-- loop Loop_Stmt. The block is encased in an if statement If_Stmt with
-- condition Cond. If_Stmt is Empty when there is no condition provided.
function Is_Array_Iteration (N : Node_Id) return Boolean;
-- Determine whether loop statement N denotes an Ada 2012 iteration over
-- an array object.
-----------------------------
-- Build_Conditional_Block --
-----------------------------
procedure Build_Conditional_Block
(Loc : Source_Ptr;
Cond : Node_Id;
Loop_Stmt : Node_Id;
If_Stmt : out Node_Id;
Blk_Stmt : out Node_Id)
is
begin
-- Do not reanalyze the original loop statement because it is simply
-- being relocated.
Set_Analyzed (Loop_Stmt);
Blk_Stmt :=
Make_Block_Statement (Loc,
Declarations => New_List,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => New_List (Loop_Stmt)));
if Present (Cond) then
If_Stmt :=
Make_If_Statement (Loc,
Condition => Cond,
Then_Statements => New_List (Blk_Stmt));
else
If_Stmt := Empty;
end if;
end Build_Conditional_Block;
------------------------
-- Is_Array_Iteration --
------------------------
function Is_Array_Iteration (N : Node_Id) return Boolean is
Stmt : constant Node_Id := Original_Node (N);
Iter : Node_Id;
begin
if Nkind (Stmt) = N_Loop_Statement
and then Present (Iteration_Scheme (Stmt))
and then Present (Iterator_Specification (Iteration_Scheme (Stmt)))
then
Iter := Iterator_Specification (Iteration_Scheme (Stmt));
return
Of_Present (Iter) and then Is_Array_Type (Etype (Name (Iter)));
end if;
return False;
end Is_Array_Iteration;
-- Local variables
Pref : constant Node_Id := Prefix (N);
Base_Typ : constant Entity_Id := Base_Type (Etype (Pref));
Exprs : constant List_Id := Expressions (N);
Aux_Decl : Node_Id;
Blk : Node_Id := Empty;
Decls : List_Id;
Installed : Boolean;
Loc : Source_Ptr;
Loop_Id : Entity_Id;
Loop_Stmt : Node_Id;
Result : Node_Id := Empty;
Scheme : Node_Id;
Temp_Decl : Node_Id;
Temp_Id : Entity_Id;
-- Start of processing for Expand_Loop_Entry_Attribute
begin
-- Step 1: Find the related loop
-- The loop label variant of attribute 'Loop_Entry already has all the
-- information in its expression.
if Present (Exprs) then
Loop_Id := Entity (First (Exprs));
Loop_Stmt := Label_Construct (Parent (Loop_Id));
-- Climb the parent chain to find the nearest enclosing loop. Skip
-- all internally generated loops for quantified expressions and for
-- element iterators over multidimensional arrays because the pragma
-- applies to source loop.
else
Loop_Stmt := N;
while Present (Loop_Stmt) loop
if Nkind (Loop_Stmt) = N_Loop_Statement
and then Nkind (Original_Node (Loop_Stmt)) = N_Loop_Statement
and then Comes_From_Source (Original_Node (Loop_Stmt))
then
exit;
end if;
Loop_Stmt := Parent (Loop_Stmt);
end loop;
Loop_Id := Entity (Identifier (Loop_Stmt));
end if;
Loc := Sloc (Loop_Stmt);
-- Step 2: Transform the loop
-- The loop has already been transformed during the expansion of a prior
-- 'Loop_Entry attribute. Retrieve the declarative list of the block.
if Has_Loop_Entry_Attributes (Loop_Id) then
-- When the related loop name appears as the argument of attribute
-- Loop_Entry, the corresponding label construct is the generated
-- block statement. This is because the expander reuses the label.
if Nkind (Loop_Stmt) = N_Block_Statement then
Decls := Declarations (Loop_Stmt);
-- In all other cases, the loop must appear in the handled sequence
-- of statements of the generated block.
else
pragma Assert
(Nkind (Parent (Loop_Stmt)) = N_Handled_Sequence_Of_Statements
and then
Nkind (Parent (Parent (Loop_Stmt))) = N_Block_Statement);
Decls := Declarations (Parent (Parent (Loop_Stmt)));
end if;
-- Transform the loop into a conditional block
else
Set_Has_Loop_Entry_Attributes (Loop_Id);
Scheme := Iteration_Scheme (Loop_Stmt);
-- Infinite loops are transformed into:
-- declare
-- Temp1 : constant <type of Pref1> := <Pref1>;
-- . . .
-- TempN : constant <type of PrefN> := <PrefN>;
-- begin
-- loop
-- <original source statements with attribute rewrites>
-- end loop;
-- end;
if No (Scheme) then
Build_Conditional_Block (Loc,
Cond => Empty,
Loop_Stmt => Relocate_Node (Loop_Stmt),
If_Stmt => Result,
Blk_Stmt => Blk);
Result := Blk;
-- While loops are transformed into:
-- function Fnn return Boolean is
-- begin
-- <condition actions>
-- return <condition>;
-- end Fnn;
-- if Fnn then
-- declare
-- Temp1 : constant <type of Pref1> := <Pref1>;
-- . . .
-- TempN : constant <type of PrefN> := <PrefN>;
-- begin
-- loop
-- <original source statements with attribute rewrites>
-- exit when not Fnn;
-- end loop;
-- end;
-- end if;
-- Note that loops over iterators and containers are already
-- converted into while loops.
elsif Present (Condition (Scheme)) then
declare
Func_Decl : Node_Id;
Func_Id : Entity_Id;
Stmts : List_Id;
begin
Func_Id := Make_Temporary (Loc, 'F');
-- Wrap the condition of the while loop in a Boolean function.
-- This avoids the duplication of the same code which may lead
-- to gigi issues with respect to multiple declaration of the
-- same entity in the presence of side effects or checks. Note
-- that the condition actions must also be relocated into the
-- wrapping function because they may contain itypes, e.g. in
-- the case of a comparison involving slices.
-- Generate:
-- <condition actions>
-- return <condition>;
if Present (Condition_Actions (Scheme)) then
Stmts := Condition_Actions (Scheme);
else
Stmts := New_List;
end if;
Append_To (Stmts,
Make_Simple_Return_Statement (Loc,
Expression =>
New_Copy_Tree (Condition (Scheme),
New_Scope => Func_Id)));
-- Generate:
-- function Fnn return Boolean is
-- begin
-- <Stmts>
-- end Fnn;
Func_Decl :=
Make_Subprogram_Body (Loc,
Specification =>
Make_Function_Specification (Loc,
Defining_Unit_Name => Func_Id,
Result_Definition =>
New_Occurrence_Of (Standard_Boolean, Loc)),
Declarations => Empty_List,
Handled_Statement_Sequence =>
Make_Handled_Sequence_Of_Statements (Loc,
Statements => Stmts));
-- The function is inserted before the related loop. Make sure
-- to analyze it in the context of the loop's enclosing scope.
Push_Scope (Scope (Loop_Id));
Insert_Action (Loop_Stmt, Func_Decl);
Pop_Scope;
-- The analysis of the condition may have generated entities
-- (such as itypes) that are now used within the function.
-- Adjust their scopes accordingly so that their use appears
-- in their scope of definition.
declare
Ent : Entity_Id;
begin
Ent := First_Entity (Loop_Id);
while Present (Ent) loop
-- Various entities that now occur within the function
-- need to have their scope reset, but not all entities
-- associated with Loop_Id are now inside the function.
-- The function entity itself and loop parameters can
-- be outside the function, and there may be others.
-- It's not clear how the determination of what entity
-- scopes need to be adjusted can be made accurately.
-- Perhaps it will be necessary to traverse the function
-- body to find the exact entities whose scopes need to
-- be reset to the function's Entity_Id. ???
if Ekind (Ent) /= E_Loop_Parameter
and then Ent /= Func_Id
then
Set_Scope (Ent, Func_Id);
end if;
Next_Entity (Ent);
end loop;
end;
-- Transform the original while loop into an infinite loop
-- where the last statement checks the negated condition. This
-- placement ensures that the condition will not be evaluated
-- twice on the first iteration.
Set_Iteration_Scheme (Loop_Stmt, Empty);
Scheme := Empty;
-- Generate:
-- exit when not Fnn;
Append_To (Statements (Loop_Stmt),
Make_Exit_Statement (Loc,
Condition =>
Make_Op_Not (Loc,
Right_Opnd =>
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Func_Id, Loc)))));
Build_Conditional_Block (Loc,
Cond =>
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Func_Id, Loc)),
Loop_Stmt => Relocate_Node (Loop_Stmt),
If_Stmt => Result,
Blk_Stmt => Blk);
end;
-- Ada 2012 iteration over an array is transformed into:
-- if <Array_Nam>'Length (1) > 0
-- and then <Array_Nam>'Length (N) > 0
-- then
-- declare
-- Temp1 : constant <type of Pref1> := <Pref1>;
-- . . .
-- TempN : constant <type of PrefN> := <PrefN>;
-- begin
-- for X in ... loop -- multiple loops depending on dims
-- <original source statements with attribute rewrites>
-- end loop;
-- end;
-- end if;
elsif Is_Array_Iteration (Loop_Stmt) then
declare
Array_Nam : constant Entity_Id :=
Entity (Name (Iterator_Specification
(Iteration_Scheme (Original_Node (Loop_Stmt)))));
Num_Dims : constant Pos :=
Number_Dimensions (Etype (Array_Nam));
Cond : Node_Id := Empty;
Check : Node_Id;
begin
-- Generate a check which determines whether all dimensions of
-- the array are non-null.
for Dim in 1 .. Num_Dims loop
Check :=
Make_Op_Gt (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Array_Nam, Loc),
Attribute_Name => Name_Length,
Expressions => New_List (
Make_Integer_Literal (Loc, Dim))),
Right_Opnd =>
Make_Integer_Literal (Loc, 0));
if No (Cond) then
Cond := Check;
else
Cond :=
Make_And_Then (Loc,
Left_Opnd => Cond,
Right_Opnd => Check);
end if;
end loop;
Build_Conditional_Block (Loc,
Cond => Cond,
Loop_Stmt => Relocate_Node (Loop_Stmt),
If_Stmt => Result,
Blk_Stmt => Blk);
end;
-- For loops are transformed into:
-- if <Low> <= <High> then
-- declare
-- Temp1 : constant <type of Pref1> := <Pref1>;
-- . . .
-- TempN : constant <type of PrefN> := <PrefN>;
-- begin
-- for <Def_Id> in <Low> .. <High> loop
-- <original source statements with attribute rewrites>
-- end loop;
-- end;
-- end if;
elsif Present (Loop_Parameter_Specification (Scheme)) then
declare
Loop_Spec : constant Node_Id :=
Loop_Parameter_Specification (Scheme);
Cond : Node_Id;
Subt_Def : Node_Id;
begin
Subt_Def := Discrete_Subtype_Definition (Loop_Spec);
-- When the loop iterates over a subtype indication with a
-- range, use the low and high bounds of the subtype itself.
if Nkind (Subt_Def) = N_Subtype_Indication then
Subt_Def := Scalar_Range (Etype (Subt_Def));
end if;
pragma Assert (Nkind (Subt_Def) = N_Range);
-- Generate
-- Low <= High
Cond :=
Make_Op_Le (Loc,
Left_Opnd => New_Copy_Tree (Low_Bound (Subt_Def)),
Right_Opnd => New_Copy_Tree (High_Bound (Subt_Def)));
Build_Conditional_Block (Loc,
Cond => Cond,
Loop_Stmt => Relocate_Node (Loop_Stmt),
If_Stmt => Result,
Blk_Stmt => Blk);
end;
end if;
Decls := Declarations (Blk);
end if;
-- Step 3: Create a constant to capture the value of the prefix at the
-- entry point into the loop.
Temp_Id := Make_Temporary (Loc, 'P');
-- Preserve the tag of the prefix by offering a specific view of the
-- class-wide version of the prefix.
if Is_Tagged_Type (Base_Typ) then
Tagged_Case : declare
CW_Temp : Entity_Id;
CW_Typ : Entity_Id;
begin
-- Generate:
-- CW_Temp : constant Base_Typ'Class := Base_Typ'Class (Pref);
CW_Temp := Make_Temporary (Loc, 'T');
CW_Typ := Class_Wide_Type (Base_Typ);
Aux_Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => CW_Temp,
Constant_Present => True,
Object_Definition => New_Occurrence_Of (CW_Typ, Loc),
Expression =>
Convert_To (CW_Typ, Relocate_Node (Pref)));
Append_To (Decls, Aux_Decl);
-- Generate:
-- Temp : Base_Typ renames Base_Typ (CW_Temp);
Temp_Decl :=
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier => Temp_Id,
Subtype_Mark => New_Occurrence_Of (Base_Typ, Loc),
Name =>
Convert_To (Base_Typ, New_Occurrence_Of (CW_Temp, Loc)));
Append_To (Decls, Temp_Decl);
end Tagged_Case;
-- Untagged case
else
Untagged_Case : declare
Temp_Expr : Node_Id;
begin
Aux_Decl := Empty;
-- Generate a nominal type for the constant when the prefix is of
-- a constrained type. This is achieved by setting the Etype of
-- the relocated prefix to its base type. Since the prefix is now
-- the initialization expression of the constant, its freezing
-- will produce a proper nominal type.
Temp_Expr := Relocate_Node (Pref);
Set_Etype (Temp_Expr, Base_Typ);
-- Generate:
-- Temp : constant Base_Typ := Pref;
Temp_Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Temp_Id,
Constant_Present => True,
Object_Definition => New_Occurrence_Of (Base_Typ, Loc),
Expression => Temp_Expr);
Append_To (Decls, Temp_Decl);
end Untagged_Case;
end if;
-- Step 4: Analyze all bits
Installed := Current_Scope = Scope (Loop_Id);
-- Depending on the pracement of attribute 'Loop_Entry relative to the
-- associated loop, ensure the proper visibility for analysis.
if not Installed then
Push_Scope (Scope (Loop_Id));
end if;
-- The analysis of the conditional block takes care of the constant
-- declaration.
if Present (Result) then
Rewrite (Loop_Stmt, Result);
Analyze (Loop_Stmt);
-- The conditional block was analyzed when a previous 'Loop_Entry was
-- expanded. There is no point in reanalyzing the block, simply analyze
-- the declaration of the constant.
else
if Present (Aux_Decl) then
Analyze (Aux_Decl);
end if;
Analyze (Temp_Decl);
end if;
Rewrite (N, New_Occurrence_Of (Temp_Id, Loc));
Analyze (N);
if not Installed then
Pop_Scope;
end if;
end Expand_Loop_Entry_Attribute;
------------------------------
-- Expand_Min_Max_Attribute --
------------------------------
procedure Expand_Min_Max_Attribute (N : Node_Id) is
begin
-- Min and Max are handled by the back end (except that static cases
-- have already been evaluated during semantic processing, although the
-- back end should not count on this). The one bit of special processing
-- required in the normal case is that these two attributes typically
-- generate conditionals in the code, so check the relevant restriction.
Check_Restriction (No_Implicit_Conditionals, N);
end Expand_Min_Max_Attribute;
----------------------------------
-- Expand_N_Attribute_Reference --
----------------------------------
procedure Expand_N_Attribute_Reference (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Pref : constant Node_Id := Prefix (N);
Exprs : constant List_Id := Expressions (N);
function Get_Integer_Type (Typ : Entity_Id) return Entity_Id;
-- Return a small integer type appropriate for the enumeration type
procedure Rewrite_Attribute_Proc_Call (Pname : Entity_Id);
-- Rewrites an attribute for Read, Write, Output, or Put_Image with a
-- call to the appropriate TSS procedure. Pname is the entity for the
-- procedure to call.
----------------------
-- Get_Integer_Type --
----------------------
function Get_Integer_Type (Typ : Entity_Id) return Entity_Id is
Siz : constant Uint := Esize (Base_Type (Typ));
begin
-- We need to accommodate invalid values of the base type since we
-- accept them for Enum_Rep and Pos, so we reason on the Esize.
return Small_Integer_Type_For (Siz, Uns => Is_Unsigned_Type (Typ));
end Get_Integer_Type;
---------------------------------
-- Rewrite_Attribute_Proc_Call --
---------------------------------
procedure Rewrite_Attribute_Proc_Call (Pname : Entity_Id) is
Item : constant Node_Id := Next (First (Exprs));
Item_Typ : constant Entity_Id := Etype (Item);
Formal : constant Entity_Id := Next_Formal (First_Formal (Pname));
Formal_Typ : constant Entity_Id := Etype (Formal);
Is_Written : constant Boolean := Ekind (Formal) /= E_In_Parameter;
begin
-- The expansion depends on Item, the second actual, which is
-- the object being streamed in or out.
-- If the item is a component of a packed array type, and
-- a conversion is needed on exit, we introduce a temporary to
-- hold the value, because otherwise the packed reference will
-- not be properly expanded.
if Nkind (Item) = N_Indexed_Component
and then Is_Packed (Base_Type (Etype (Prefix (Item))))
and then Base_Type (Item_Typ) /= Base_Type (Formal_Typ)
and then Is_Written
then
declare
Temp : constant Entity_Id := Make_Temporary (Loc, 'V');
Decl : Node_Id;
Assn : Node_Id;
begin
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Temp,
Object_Definition => New_Occurrence_Of (Formal_Typ, Loc));
Set_Etype (Temp, Formal_Typ);
Assn :=
Make_Assignment_Statement (Loc,
Name => New_Copy_Tree (Item),
Expression =>
Unchecked_Convert_To
(Item_Typ, New_Occurrence_Of (Temp, Loc)));
Rewrite (Item, New_Occurrence_Of (Temp, Loc));
Insert_Actions (N,
New_List (
Decl,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (Pname, Loc),
Parameter_Associations => Exprs),
Assn));
Rewrite (N, Make_Null_Statement (Loc));
return;
end;
end if;
-- For the class-wide dispatching cases, and for cases in which
-- the base type of the second argument matches the base type of
-- the corresponding formal parameter (that is to say the stream
-- operation is not inherited), we are all set, and can use the
-- argument unchanged.
if not Is_Class_Wide_Type (Entity (Pref))
and then not Is_Class_Wide_Type (Etype (Item))
and then Base_Type (Item_Typ) /= Base_Type (Formal_Typ)
then
-- Perform a view conversion when either the argument or the
-- formal parameter are of a private type.
if Is_Private_Type (Base_Type (Formal_Typ))
or else Is_Private_Type (Base_Type (Item_Typ))
then
Rewrite (Item,
Unchecked_Convert_To (Formal_Typ, Relocate_Node (Item)));
-- Otherwise perform a regular type conversion to ensure that all
-- relevant checks are installed.
else
Rewrite (Item, Convert_To (Formal_Typ, Relocate_Node (Item)));
end if;
-- For untagged derived types set Assignment_OK, to prevent
-- copies from being created when the unchecked conversion
-- is expanded (which would happen in Remove_Side_Effects
-- if Expand_N_Unchecked_Conversion were allowed to call
-- Force_Evaluation). The copy could violate Ada semantics in
-- cases such as an actual that is an out parameter. Note that
-- this approach is also used in exp_ch7 for calls to controlled
-- type operations to prevent problems with actuals wrapped in
-- unchecked conversions.
if Is_Untagged_Derivation (Etype (Expression (Item))) then
Set_Assignment_OK (Item);
end if;
end if;
-- The stream operation to call might be a renaming created by an
-- attribute definition clause, and might not be frozen yet. Ensure
-- that it has the necessary extra formals.
if not Is_Frozen (Pname) then
Create_Extra_Formals (Pname);
end if;
-- And now rewrite the call
Rewrite (N,
Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (Pname, Loc),
Parameter_Associations => Exprs));
Analyze (N);
end Rewrite_Attribute_Proc_Call;
Typ : constant Entity_Id := Etype (N);
Btyp : constant Entity_Id := Base_Type (Typ);
Ptyp : constant Entity_Id := Etype (Pref);
Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
-- Start of processing for Expand_N_Attribute_Reference
begin
-- Do required validity checking, if enabled. Do not apply check to
-- output parameters of an Asm instruction, since the value of this
-- is not set till after the attribute has been elaborated, and do
-- not apply the check to the arguments of a 'Read or 'Input attribute
-- reference since the scalar argument is an OUT scalar.
if Validity_Checks_On and then Validity_Check_Operands
and then Id /= Attribute_Asm_Output
and then Id /= Attribute_Read
and then Id /= Attribute_Input
then
declare
Expr : Node_Id;
begin
Expr := First (Expressions (N));
while Present (Expr) loop
Ensure_Valid (Expr);
Next (Expr);
end loop;
end;
end if;
-- Ada 2005 (AI-318-02): If attribute prefix is a call to a build-in-
-- place function, then a temporary return object needs to be created
-- and access to it must be passed to the function.
if Is_Build_In_Place_Function_Call (Pref) then
-- If attribute is 'Old, the context is a postcondition, and
-- the temporary must go in the corresponding subprogram, not
-- the postcondition function or any created blocks, as when
-- the attribute appears in a quantified expression. This is
-- handled below in the expansion of the attribute.
if Attribute_Name (Parent (Pref)) = Name_Old then
null;
else
Make_Build_In_Place_Call_In_Anonymous_Context (Pref);
end if;
-- Ada 2005 (AI-318-02): Specialization of the previous case for prefix
-- containing build-in-place function calls whose returned object covers
-- interface types.
elsif Present (Unqual_BIP_Iface_Function_Call (Pref)) then
Make_Build_In_Place_Iface_Call_In_Anonymous_Context (Pref);
end if;
-- If prefix is a protected type name, this is a reference to the
-- current instance of the type. For a component definition, nothing
-- to do (expansion will occur in the init proc). In other contexts,
-- rewrite into reference to current instance.
if Is_Protected_Self_Reference (Pref)
and then not
(Nkind (Parent (N)) in N_Index_Or_Discriminant_Constraint
| N_Discriminant_Association
and then Nkind (Parent (Parent (Parent (Parent (N))))) =
N_Component_Definition)
-- No action needed for these attributes since the current instance
-- will be rewritten to be the name of the _object parameter
-- associated with the enclosing protected subprogram (see below).
and then Id /= Attribute_Access
and then Id /= Attribute_Unchecked_Access
and then Id /= Attribute_Unrestricted_Access
then
Rewrite (Pref, Concurrent_Ref (Pref));
Analyze (Pref);
end if;
-- Remaining processing depends on specific attribute
-- Note: individual sections of the following case statement are
-- allowed to assume there is no code after the case statement, and
-- are legitimately allowed to execute return statements if they have
-- nothing more to do.
case Id is
-- Attributes related to Ada 2012 iterators
when Attribute_Constant_Indexing
| Attribute_Default_Iterator
| Attribute_Implicit_Dereference
| Attribute_Iterable
| Attribute_Iterator_Element
| Attribute_Variable_Indexing
=>
null;
-- Internal attributes used to deal with Ada 2012 delayed aspects. These
-- were already rejected by the parser. Thus they shouldn't appear here.
when Internal_Attribute_Id =>
raise Program_Error;
------------
-- Access --
------------
when Attribute_Access
| Attribute_Unchecked_Access
| Attribute_Unrestricted_Access
=>
Access_Cases : declare
Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
Btyp_DDT : Entity_Id;
function Enclosing_Object (N : Node_Id) return Node_Id;
-- If N denotes a compound name (selected component, indexed
-- component, or slice), returns the name of the outermost such
-- enclosing object. Otherwise returns N. If the object is a
-- renaming, then the renamed object is returned.
----------------------
-- Enclosing_Object --
----------------------
function Enclosing_Object (N : Node_Id) return Node_Id is
Obj_Name : Node_Id;
begin
Obj_Name := N;
while Nkind (Obj_Name) in N_Selected_Component
| N_Indexed_Component
| N_Slice
loop
Obj_Name := Prefix (Obj_Name);
end loop;
return Get_Referenced_Object (Obj_Name);
end Enclosing_Object;
-- Local declarations
Enc_Object : constant Node_Id := Enclosing_Object (Ref_Object);
-- Start of processing for Access_Cases
begin
Btyp_DDT := Designated_Type (Btyp);
-- Handle designated types that come from the limited view
if From_Limited_With (Btyp_DDT)
and then Has_Non_Limited_View (Btyp_DDT)
then
Btyp_DDT := Non_Limited_View (Btyp_DDT);
end if;
-- In order to improve the text of error messages, the designated
-- type of access-to-subprogram itypes is set by the semantics as
-- the associated subprogram entity (see sem_attr). Now we replace
-- such node with the proper E_Subprogram_Type itype.
if Id = Attribute_Unrestricted_Access
and then Is_Subprogram (Directly_Designated_Type (Typ))
then
-- The following conditions ensure that this special management
-- is done only for "Address!(Prim'Unrestricted_Access)" nodes.
-- At this stage other cases in which the designated type is
-- still a subprogram (instead of an E_Subprogram_Type) are
-- wrong because the semantics must have overridden the type of
-- the node with the type imposed by the context.
if Nkind (Parent (N)) = N_Unchecked_Type_Conversion
and then Is_RTE (Etype (Parent (N)), RE_Prim_Ptr)
then
Set_Etype (N, RTE (RE_Prim_Ptr));
else
declare
Subp : constant Entity_Id :=
Directly_Designated_Type (Typ);
Etyp : Entity_Id;
Extra : Entity_Id := Empty;
New_Formal : Entity_Id;
Old_Formal : Entity_Id := First_Formal (Subp);
Subp_Typ : Entity_Id;
begin
Subp_Typ := Create_Itype (E_Subprogram_Type, N);
Copy_Strub_Mode (Subp_Typ, Subp);
Set_Etype (Subp_Typ, Etype (Subp));
Set_Returns_By_Ref (Subp_Typ, Returns_By_Ref (Subp));
if Present (Old_Formal) then
New_Formal := New_Copy (Old_Formal);
Set_First_Entity (Subp_Typ, New_Formal);
loop
Set_Scope (New_Formal, Subp_Typ);
Etyp := Etype (New_Formal);
-- Handle itypes. There is no need to duplicate
-- here the itypes associated with record types
-- (i.e the implicit full view of private types).
if Is_Itype (Etyp)
and then Ekind (Base_Type (Etyp)) /= E_Record_Type
then
Extra := New_Copy (Etyp);
Set_Parent (Extra, New_Formal);
Set_Etype (New_Formal, Extra);
Set_Scope (Extra, Subp_Typ);
end if;
Extra := New_Formal;
Next_Formal (Old_Formal);
exit when No (Old_Formal);
Link_Entities (New_Formal, New_Copy (Old_Formal));
Next_Entity (New_Formal);
end loop;
Unlink_Next_Entity (New_Formal);
Set_Last_Entity (Subp_Typ, Extra);
end if;
-- Now that the explicit formals have been duplicated,
-- any extra formals needed by the subprogram must be
-- created.
if Present (Extra) then
Set_Extra_Formal (Extra, Empty);
end if;
Create_Extra_Formals (Subp_Typ);
Set_Directly_Designated_Type (Typ, Subp_Typ);
end;
end if;
end if;
if Is_Access_Protected_Subprogram_Type (Btyp) then
Expand_Access_To_Protected_Op (N, Pref, Typ);
-- If prefix is a subprogram that has class-wide preconditions and
-- an indirect-call wrapper (ICW) of such subprogram is available
-- then replace the prefix by the ICW.
elsif Is_Access_Subprogram_Type (Btyp)
and then Is_Entity_Name (Pref)
and then Present (Class_Preconditions (Entity (Pref)))
and then Present (Indirect_Call_Wrapper (Entity (Pref)))
then
Rewrite (Pref,
New_Occurrence_Of
(Indirect_Call_Wrapper (Entity (Pref)), Loc));
Analyze_And_Resolve (N, Typ);
-- If prefix is a type name, this is a reference to the current
-- instance of the type, within its initialization procedure.
elsif Is_Entity_Name (Pref)
and then Is_Type (Entity (Pref))
then
declare
Par : Node_Id;
Formal : Entity_Id;
begin
-- If the current instance name denotes a task type, then
-- the access attribute is rewritten to be the name of the
-- "_task" parameter associated with the task type's task
-- procedure. An unchecked conversion is applied to ensure
-- a type match in cases of expander-generated calls (e.g.
-- init procs).
if Is_Task_Type (Entity (Pref)) then
Formal :=
First_Entity (Get_Task_Body_Procedure (Entity (Pref)));
while Present (Formal) loop
exit when Chars (Formal) = Name_uTask;
Next_Entity (Formal);
end loop;
pragma Assert (Present (Formal));
Rewrite (N,
Unchecked_Convert_To (Typ,
New_Occurrence_Of (Formal, Loc)));
Set_Etype (N, Typ);
elsif Is_Protected_Type (Entity (Pref)) then
-- No action needed for current instance located in a
-- component definition (expansion will occur in the
-- init proc)
if Is_Protected_Type (Current_Scope) then
null;
-- If the current instance reference is located in a
-- protected subprogram or entry then rewrite the access
-- attribute to be the name of the "_object" parameter.
-- An unchecked conversion is applied to ensure a type
-- match in cases of expander-generated calls (e.g. init
-- procs).
-- The code may be nested in a block, so find enclosing
-- scope that is a protected operation.
else
declare
Subp : Entity_Id;
begin
Subp := Current_Scope;
while Ekind (Subp) in E_Loop | E_Block loop
Subp := Scope (Subp);
end loop;
Formal :=
First_Entity
(Protected_Body_Subprogram (Subp));
-- For a protected subprogram the _Object parameter
-- is the protected record, so we create an access
-- to it. The _Object parameter of an entry is an
-- address.
if Ekind (Subp) = E_Entry then
Rewrite (N,
Unchecked_Convert_To (Typ,
New_Occurrence_Of (Formal, Loc)));
Set_Etype (N, Typ);
else
Rewrite (N,
Unchecked_Convert_To (Typ,
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Unrestricted_Access,
Prefix =>
New_Occurrence_Of (Formal, Loc))));
Analyze_And_Resolve (N);
end if;
end;
end if;
-- The expression must appear in a default expression,
-- (which in the initialization procedure is the right-hand
-- side of an assignment), and not in a discriminant
-- constraint.
else
Par := Parent (N);
while Present (Par) loop
exit when Nkind (Par) = N_Assignment_Statement;
if Nkind (Par) = N_Component_Declaration then
return;
end if;
Par := Parent (Par);
end loop;
if Present (Par) then
Rewrite (N,
Make_Attribute_Reference (Loc,
Prefix => Make_Identifier (Loc, Name_uInit),
Attribute_Name => Attribute_Name (N)));
Analyze_And_Resolve (N, Typ);
end if;
end if;
end;
-- If the prefix of an Access attribute is a dereference of an
-- access parameter (or a renaming of such a dereference, or a
-- subcomponent of such a dereference) and the context is a
-- general access type (including the type of an object or
-- component with an access_definition, but not the anonymous
-- type of an access parameter or access discriminant), then
-- apply an accessibility check to the access parameter. We used
-- to rewrite the access parameter as a type conversion, but that
-- could only be done if the immediate prefix of the Access
-- attribute was the dereference, and didn't handle cases where
-- the attribute is applied to a subcomponent of the dereference,
-- since there's generally no available, appropriate access type
-- to convert to in that case. The attribute is passed as the
-- point to insert the check, because the access parameter may
-- come from a renaming, possibly in a different scope, and the
-- check must be associated with the attribute itself.
elsif Id = Attribute_Access
and then Nkind (Enc_Object) = N_Explicit_Dereference
and then Is_Entity_Name (Prefix (Enc_Object))
and then (Ekind (Btyp) = E_General_Access_Type
or else Is_Local_Anonymous_Access (Btyp))
and then Is_Formal (Entity (Prefix (Enc_Object)))
and then Ekind (Etype (Entity (Prefix (Enc_Object))))
= E_Anonymous_Access_Type
and then Present (Extra_Accessibility
(Entity (Prefix (Enc_Object))))
and then not No_Dynamic_Accessibility_Checks_Enabled (Enc_Object)
then
Apply_Accessibility_Check (Prefix (Enc_Object), Typ, N);
-- Ada 2005 (AI-251): If the designated type is an interface we
-- add an implicit conversion to force the displacement of the
-- pointer to reference the secondary dispatch table.
elsif Is_Interface (Btyp_DDT)
and then (Comes_From_Source (N)
or else Comes_From_Source (Ref_Object)
or else (Nkind (Ref_Object) in N_Has_Chars
and then Chars (Ref_Object) = Name_uInit))
then
if Nkind (Ref_Object) /= N_Explicit_Dereference then
-- No implicit conversion required if types match, or if
-- the prefix is the class_wide_type of the interface. In
-- either case passing an object of the interface type has
-- already set the pointer correctly.
if Btyp_DDT = Etype (Ref_Object)
or else (Is_Class_Wide_Type (Etype (Ref_Object))
and then
Class_Wide_Type (Btyp_DDT) = Etype (Ref_Object))
then
null;
else
Rewrite (Prefix (N),
Convert_To (Btyp_DDT,
New_Copy_Tree (Prefix (N))));
Analyze_And_Resolve (Prefix (N), Btyp_DDT);
end if;
-- When the object is an explicit dereference, convert the
-- dereference's prefix.
else
declare
Obj_DDT : constant Entity_Id :=
Base_Type
(Directly_Designated_Type
(Etype (Prefix (Ref_Object))));
begin
-- No implicit conversion required if designated types
-- match.
if Obj_DDT /= Btyp_DDT
and then not (Is_Class_Wide_Type (Obj_DDT)
and then Etype (Obj_DDT) = Btyp_DDT)
then
Rewrite (N,
Convert_To (Typ,
New_Copy_Tree (Prefix (Ref_Object))));
Analyze_And_Resolve (N, Typ);
end if;
end;
end if;
end if;
end Access_Cases;
--------------
-- Adjacent --
--------------
-- Transforms 'Adjacent into a call to the floating-point attribute
-- function Adjacent in Fat_xxx (where xxx is the root type)
when Attribute_Adjacent =>
Expand_Fpt_Attribute_RR (N);
-------------
-- Address --
-------------
when Attribute_Address => Address : declare
Task_Proc : Entity_Id;
function Is_Unnested_Component_Init (N : Node_Id) return Boolean;
-- Returns True if N is being used to initialize a component of
-- an activation record object where the component corresponds to
-- the object denoted by the prefix of the attribute N.
function Is_Unnested_Component_Init (N : Node_Id) return Boolean is
begin
return Present (Parent (N))
and then Nkind (Parent (N)) = N_Assignment_Statement
and then Is_Entity_Name (Pref)
and then Present (Activation_Record_Component (Entity (Pref)))
and then Nkind (Name (Parent (N))) = N_Selected_Component
and then Entity (Selector_Name (Name (Parent (N)))) =
Activation_Record_Component (Entity (Pref));
end Is_Unnested_Component_Init;
-- Start of processing for Address
begin
-- If the prefix is a task or a task type, the useful address is that
-- of the procedure for the task body, i.e. the actual program unit.
-- We replace the original entity with that of the procedure.
if Is_Entity_Name (Pref)
and then Is_Task_Type (Entity (Pref))
then
Task_Proc := Next_Entity (Root_Type (Ptyp));
while Present (Task_Proc) loop
exit when Ekind (Task_Proc) = E_Procedure
and then Etype (First_Formal (Task_Proc)) =
Corresponding_Record_Type (Ptyp);
Next_Entity (Task_Proc);
end loop;
if Present (Task_Proc) then
Set_Entity (Pref, Task_Proc);
Set_Etype (Pref, Etype (Task_Proc));
end if;
-- Similarly, the address of a protected operation is the address
-- of the corresponding protected body, regardless of the protected
-- object from which it is selected.
elsif Nkind (Pref) = N_Selected_Component
and then Is_Subprogram (Entity (Selector_Name (Pref)))
and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref))))
then
Rewrite (Pref,
New_Occurrence_Of (
External_Subprogram (Entity (Selector_Name (Pref))), Loc));
elsif Nkind (Pref) = N_Explicit_Dereference
and then Ekind (Ptyp) = E_Subprogram_Type
and then Convention (Ptyp) = Convention_Protected
then
-- The prefix is be a dereference of an access_to_protected_
-- subprogram. The desired address is the second component of
-- the record that represents the access.
declare
Addr : constant Entity_Id := Etype (N);
Ptr : constant Node_Id := Prefix (Pref);
T : constant Entity_Id :=
Equivalent_Type (Base_Type (Etype (Ptr)));
begin
Rewrite (N,
Unchecked_Convert_To (Addr,
Make_Selected_Component (Loc,
Prefix => Unchecked_Convert_To (T, Ptr),
Selector_Name => New_Occurrence_Of (
Next_Entity (First_Entity (T)), Loc))));
Analyze_And_Resolve (N, Addr);
end;
-- Ada 2005 (AI-251): Class-wide interface objects are always
-- "displaced" to reference the tag associated with the interface
-- type. In order to obtain the real address of such objects we
-- generate a call to a run-time subprogram that returns the base
-- address of the object. This call is not generated in cases where
-- the attribute is being used to initialize a component of an
-- activation record object where the component corresponds to
-- prefix of the attribute (for back ends that require "unnesting"
-- of nested subprograms), since the address needs to be assigned
-- as-is to such components.
elsif Is_Class_Wide_Type (Ptyp)
and then Is_Interface (Underlying_Type (Ptyp))
and then Tagged_Type_Expansion
and then not (Nkind (Pref) in N_Has_Entity
and then Is_Subprogram (Entity (Pref)))
and then not Is_Unnested_Component_Init (N)
then
Rewrite (N,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Base_Address), Loc),
Parameter_Associations => New_List (
Relocate_Node (N))));
Analyze (N);
return;
end if;
-- Deal with packed array reference, other cases are handled by
-- the back end.
if Involves_Packed_Array_Reference (Pref) then
Expand_Packed_Address_Reference (N);
end if;
end Address;
---------------
-- Alignment --
---------------
when Attribute_Alignment => Alignment : declare
New_Node : Node_Id;
begin
-- For class-wide types, X'Class'Alignment is transformed into a
-- direct reference to the Alignment of the class type, so that the
-- back end does not have to deal with the X'Class'Alignment
-- reference.
if Is_Entity_Name (Pref)
and then Is_Class_Wide_Type (Entity (Pref))
then
Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
return;
-- For x'Alignment applied to an object of a class wide type,
-- transform X'Alignment into a call to the predefined primitive
-- operation _Alignment applied to X.
elsif Is_Class_Wide_Type (Ptyp) then
New_Node :=
Make_Attribute_Reference (Loc,
Prefix => Pref,
Attribute_Name => Name_Tag);
New_Node := Build_Get_Alignment (Loc, New_Node);
-- Case where the context is an unchecked conversion to a specific
-- integer type. We directly convert from the alignment's type.
if Nkind (Parent (N)) = N_Unchecked_Type_Conversion then
Rewrite (N, New_Node);
Analyze_And_Resolve (N);
return;
-- Case where the context is a specific integer type with which
-- the original attribute was compatible. But the alignment has a
-- specific type in a-tags.ads (Standard.Natural) so, in order to
-- preserve type compatibility, we must convert explicitly.
elsif Typ /= Standard_Natural then
New_Node := Convert_To (Typ, New_Node);
end if;
Rewrite (N, New_Node);
Analyze_And_Resolve (N, Typ);
return;
-- For all other cases, we just have to deal with the case of
-- the fact that the result can be universal.
else
Apply_Universal_Integer_Attribute_Checks (N);
end if;
end Alignment;
---------------------------
-- Asm_Input, Asm_Output --
---------------------------
-- The Asm_Input and Asm_Output attributes are not expanded at this
-- stage, but will be eliminated in the expansion of the Asm call,
-- see Exp_Intr for details. So the back end will never see them.
when Attribute_Asm_Input
| Attribute_Asm_Output
=>
null;
---------
-- Bit --
---------
-- We compute this if a packed array reference was present, otherwise we
-- leave the computation up to the back end.
when Attribute_Bit =>
if Involves_Packed_Array_Reference (Pref) then
Expand_Packed_Bit_Reference (N);
else
Apply_Universal_Integer_Attribute_Checks (N);
end if;
------------------
-- Bit_Position --
------------------
-- We leave the computation up to the back end, since we don't know what
-- layout will be chosen if no component clause was specified.
when Attribute_Bit_Position =>
Apply_Universal_Integer_Attribute_Checks (N);
------------------
-- Body_Version --
------------------
-- A reference to P'Body_Version or P'Version is expanded to
-- Vnn : Unsigned;
-- pragma Import (C, Vnn, "uuuuT");
-- ...
-- Get_Version_String (Vnn)
-- where uuuu is the unit name (dots replaced by double underscore)
-- and T is B for the cases of Body_Version, or Version applied to a
-- subprogram acting as its own spec, and S for Version applied to a
-- subprogram spec or package. This sequence of code references the
-- unsigned constant created in the main program by the binder.
-- A special exception occurs for Standard, where the string returned
-- is a copy of the library string in gnatvsn.ads.
when Attribute_Body_Version
| Attribute_Version
=>
Version : declare
E : constant Entity_Id := Make_Temporary (Loc, 'V');
Pent : Entity_Id;
S : String_Id;
begin
-- If not library unit, get to containing library unit
Pent := Entity (Pref);
while Pent /= Standard_Standard
and then Scope (Pent) /= Standard_Standard
and then not Is_Child_Unit (Pent)
loop
Pent := Scope (Pent);
end loop;
-- Special case Standard and Standard.ASCII
if Pent = Standard_Standard or else Pent = Standard_ASCII then
Rewrite (N,
Make_String_Literal (Loc,
Strval => Verbose_Library_Version));
-- All other cases
else
-- Build required string constant
Get_Name_String (Get_Unit_Name (Pent));
Start_String;
for J in 1 .. Name_Len - 2 loop
if Name_Buffer (J) = '.' then
Store_String_Chars ("__");
else
Store_String_Char (Get_Char_Code (Name_Buffer (J)));
end if;
end loop;
-- Case of subprogram acting as its own spec, always use body
if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification
and then Nkind (Parent (Declaration_Node (Pent))) =
N_Subprogram_Body
and then Acts_As_Spec (Parent (Declaration_Node (Pent)))
then
Store_String_Chars ("B");
-- Case of no body present, always use spec
elsif not Unit_Requires_Body (Pent) then
Store_String_Chars ("S");
-- Otherwise use B for Body_Version, S for spec
elsif Id = Attribute_Body_Version then
Store_String_Chars ("B");
else
Store_String_Chars ("S");
end if;
S := End_String;
Lib.Version_Referenced (S);
-- Insert the object declaration
Insert_Actions (N, New_List (
Make_Object_Declaration (Loc,
Defining_Identifier => E,
Object_Definition =>
New_Occurrence_Of (RTE (RE_Unsigned), Loc))));
-- Set entity as imported with correct external name
Set_Is_Imported (E);
Set_Interface_Name (E, Make_String_Literal (Loc, S));
-- Set entity as internal to ensure proper Sprint output of its
-- implicit importation.
Set_Is_Internal (E);
-- And now rewrite original reference
Rewrite (N,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Get_Version_String), Loc),
Parameter_Associations => New_List (
New_Occurrence_Of (E, Loc))));
end if;
Analyze_And_Resolve (N, RTE (RE_Version_String));
end Version;
-------------
-- Ceiling --
-------------
-- Transforms 'Ceiling into a call to the floating-point attribute
-- function Ceiling in Fat_xxx (where xxx is the root type)
when Attribute_Ceiling =>
Expand_Fpt_Attribute_R (N);
--------------
-- Callable --
--------------
-- Transforms 'Callable attribute into a call to the Callable function
when Attribute_Callable =>
-- We have an object of a task interface class-wide type as a prefix
-- to Callable. Generate:
-- callable (Task_Id (Pref._disp_get_task_id));
if Ada_Version >= Ada_2005
and then Ekind (Ptyp) = E_Class_Wide_Type
and then Is_Interface (Ptyp)
and then Is_Task_Interface (Ptyp)
then
Rewrite (N,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Callable), Loc),
Parameter_Associations => New_List (
Unchecked_Convert_To
(RTE (RO_ST_Task_Id),
Build_Disp_Get_Task_Id_Call (Pref)))));
else
Rewrite (N, Build_Call_With_Task (Pref, RTE (RE_Callable)));
end if;
Analyze_And_Resolve (N, Standard_Boolean);
------------
-- Caller --
------------
-- Transforms 'Caller attribute into a call to either the
-- Task_Entry_Caller or the Protected_Entry_Caller function.
when Attribute_Caller => Caller : declare
Id_Kind : constant Entity_Id := RTE (RO_AT_Task_Id);
Ent : constant Entity_Id := Entity (Pref);
Conctype : constant Entity_Id := Scope (Ent);
Nest_Depth : Nat := 0;
Name : Node_Id;
S : Entity_Id;
begin
-- Protected case
if Is_Protected_Type (Conctype) then
case Corresponding_Runtime_Package (Conctype) is
when System_Tasking_Protected_Objects_Entries =>
Name :=
New_Occurrence_Of
(RTE (RE_Protected_Entry_Caller), Loc);
when System_Tasking_Protected_Objects_Single_Entry =>
Name :=
New_Occurrence_Of
(RTE (RE_Protected_Single_Entry_Caller), Loc);
when others =>
raise Program_Error;
end case;
Rewrite (N,
Unchecked_Convert_To (Id_Kind,
Make_Function_Call (Loc,
Name => Name,
Parameter_Associations => New_List (
New_Occurrence_Of
(Find_Protection_Object (Current_Scope), Loc)))));
-- Task case
else
-- Determine the nesting depth of the E'Caller attribute, that
-- is, how many accept statements are nested within the accept
-- statement for E at the point of E'Caller. The runtime uses
-- this depth to find the specified entry call.
for J in reverse 0 .. Scope_Stack.Last loop
S := Scope_Stack.Table (J).Entity;
-- We should not reach the scope of the entry, as it should
-- already have been checked in Sem_Attr that this attribute
-- reference is within a matching accept statement.
pragma Assert (S /= Conctype);
if S = Ent then
exit;
elsif Is_Entry (S) then
Nest_Depth := Nest_Depth + 1;
end if;
end loop;
Rewrite (N,
Unchecked_Convert_To (Id_Kind,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Task_Entry_Caller), Loc),
Parameter_Associations => New_List (
Make_Integer_Literal (Loc,
Intval => Nest_Depth)))));
end if;
Analyze_And_Resolve (N, Id_Kind);
end Caller;
--------------------
-- Component_Size --
--------------------
-- Component_Size is handled by the back end
when Attribute_Component_Size =>
Apply_Universal_Integer_Attribute_Checks (N);
-------------
-- Compose --
-------------
-- Transforms 'Compose into a call to the floating-point attribute
-- function Compose in Fat_xxx (where xxx is the root type)
-- Note: we strictly should have special code here to deal with the
-- case of absurdly negative arguments (less than Integer'First)
-- which will return a (signed) zero value, but it hardly seems
-- worth the effort. Absurdly large positive arguments will raise
-- constraint error which is fine.
when Attribute_Compose =>
Expand_Fpt_Attribute_RI (N);
-----------------
-- Constrained --
-----------------
when Attribute_Constrained => Constrained : declare
Formal_Ent : constant Entity_Id := Param_Entity (Pref);
begin
-- Reference to a parameter where the value is passed as an extra
-- actual, corresponding to the extra formal referenced by the
-- Extra_Constrained field of the corresponding formal. If this
-- is an entry in-parameter, it is replaced by a constant renaming
-- for which Extra_Constrained is never created.
if Present (Formal_Ent)
and then Ekind (Formal_Ent) /= E_Constant
and then Present (Extra_Constrained (Formal_Ent))
then
Rewrite (N,
New_Occurrence_Of
(Extra_Constrained (Formal_Ent), Loc));
-- If the prefix is an access to object, the attribute applies to
-- the designated object, so rewrite with an explicit dereference.
elsif Is_Access_Type (Ptyp)
and then
(not Is_Entity_Name (Pref) or else Is_Object (Entity (Pref)))
then
Rewrite (Pref,
Make_Explicit_Dereference (Loc, Relocate_Node (Pref)));
-- For variables with a Extra_Constrained field, we use the
-- corresponding entity.
elsif Nkind (Pref) = N_Identifier
and then Ekind (Entity (Pref)) = E_Variable
and then Present (Extra_Constrained (Entity (Pref)))
then
Rewrite (N,
New_Occurrence_Of
(Extra_Constrained (Entity (Pref)), Loc));
-- For all other cases, we can tell at compile time
else
-- For access type, apply access check as needed
if Is_Entity_Name (Pref)
and then not Is_Type (Entity (Pref))
and then Is_Access_Type (Ptyp)
then
Apply_Access_Check (N);
end if;
Rewrite (N,
New_Occurrence_Of
(Boolean_Literals
(Exp_Util.Attribute_Constrained_Static_Value (Pref)), Loc));
end if;
Analyze_And_Resolve (N, Standard_Boolean);
end Constrained;
---------------
-- Copy_Sign --
---------------
-- Transforms 'Copy_Sign into a call to the floating-point attribute
-- function Copy_Sign in Fat_xxx (where xxx is the root type).
when Attribute_Copy_Sign =>
Expand_Fpt_Attribute_RR (N);
-----------
-- Count --
-----------
-- Transforms 'Count attribute into a call to the Count function
when Attribute_Count => Count : declare
Call : Node_Id;
Conctyp : Entity_Id;
Entnam : Node_Id;
Entry_Id : Entity_Id;
Index : Node_Id;
Name : Node_Id;
begin
-- If the prefix is a member of an entry family, retrieve both
-- entry name and index. For a simple entry there is no index.
if Nkind (Pref) = N_Indexed_Component then
Entnam := Prefix (Pref);
Index := First (Expressions (Pref));
else
Entnam := Pref;
Index := Empty;
end if;
Entry_Id := Entity (Entnam);
-- Find the concurrent type in which this attribute is referenced
-- (there had better be one).
Conctyp := Current_Scope;
while not Is_Concurrent_Type (Conctyp) loop
Conctyp := Scope (Conctyp);
end loop;
-- Protected case
if Is_Protected_Type (Conctyp) then
-- No need to transform 'Count into a function call if the current
-- scope has been eliminated. In this case such transformation is
-- also not viable because the enclosing protected object is not
-- available.
if Is_Eliminated (Current_Scope) then
return;
end if;
case Corresponding_Runtime_Package (Conctyp) is
when System_Tasking_Protected_Objects_Entries =>
Name := New_Occurrence_Of (RTE (RE_Protected_Count), Loc);
Call :=
Make_Function_Call (Loc,
Name => Name,
Parameter_Associations => New_List (
New_Occurrence_Of
(Find_Protection_Object (Current_Scope), Loc),
Entry_Index_Expression
(Loc, Entry_Id, Index, Scope (Entry_Id))));
when System_Tasking_Protected_Objects_Single_Entry =>
Name :=
New_Occurrence_Of (RTE (RE_Protected_Count_Entry), Loc);
Call :=
Make_Function_Call (Loc,
Name => Name,
Parameter_Associations => New_List (
New_Occurrence_Of
(Find_Protection_Object (Current_Scope), Loc)));
when others =>
raise Program_Error;
end case;
-- Task case
else
Call :=
Make_Function_Call (Loc,
Name => New_Occurrence_Of (RTE (RE_Task_Count), Loc),
Parameter_Associations => New_List (
Entry_Index_Expression (Loc,
Entry_Id, Index, Scope (Entry_Id))));
end if;
-- The call returns type Natural but the context is universal integer
-- so any integer type is allowed. The attribute was already resolved
-- so its Etype is the required result type. If the base type of the
-- context type is other than Standard.Integer we put in a conversion
-- to the required type. This can be a normal typed conversion since
-- both input and output types of the conversion are integer types
if Base_Type (Typ) /= Base_Type (Standard_Integer) then
Rewrite (N, Convert_To (Typ, Call));
else
Rewrite (N, Call);
end if;
Analyze_And_Resolve (N, Typ);
end Count;
---------------------
-- Descriptor_Size --
---------------------
-- Descriptor_Size is handled by the back end
when Attribute_Descriptor_Size =>
Apply_Universal_Integer_Attribute_Checks (N);
---------------
-- Elab_Body --
---------------
-- This processing is shared by Elab_Spec
-- What we do is to insert the following declarations
-- procedure tnn;
-- pragma Import (C, enn, "name___elabb/s");
-- and then the Elab_Body/Spec attribute is replaced by a reference
-- to this defining identifier.
when Attribute_Elab_Body
| Attribute_Elab_Spec
=>
-- Leave attribute unexpanded in CodePeer mode: the gnat2scil
-- back-end knows how to handle these attributes directly.
if CodePeer_Mode then
return;
end if;
Elab_Body : declare
Ent : constant Entity_Id := Make_Temporary (Loc, 'E');
Str : String_Id;
Lang : Node_Id;
procedure Make_Elab_String (Nod : Node_Id);
-- Given Nod, an identifier, or a selected component, put the
-- image into the current string literal, with double underline
-- between components.
----------------------
-- Make_Elab_String --
----------------------
procedure Make_Elab_String (Nod : Node_Id) is
begin
if Nkind (Nod) = N_Selected_Component then
Make_Elab_String (Prefix (Nod));
Store_String_Char ('_');
Store_String_Char ('_');
Get_Name_String (Chars (Selector_Name (Nod)));
else
pragma Assert (Nkind (Nod) = N_Identifier);
Get_Name_String (Chars (Nod));
end if;
Store_String_Chars (Name_Buffer (1 .. Name_Len));
end Make_Elab_String;
-- Start of processing for Elab_Body/Elab_Spec
begin
-- First we need to prepare the string literal for the name of
-- the elaboration routine to be referenced.
Start_String;
Make_Elab_String (Pref);
Store_String_Chars ("___elab");
Lang := Make_Identifier (Loc, Name_C);
if Id = Attribute_Elab_Body then
Store_String_Char ('b');
else
Store_String_Char ('s');
end if;
Str := End_String;
Insert_Actions (N, New_List (
Make_Subprogram_Declaration (Loc,
Specification =>
Make_Procedure_Specification (Loc,
Defining_Unit_Name => Ent)),
Make_Pragma (Loc,
Chars => Name_Import,
Pragma_Argument_Associations => New_List (
Make_Pragma_Argument_Association (Loc, Expression => Lang),
Make_Pragma_Argument_Association (Loc,
Expression => Make_Identifier (Loc, Chars (Ent))),
Make_Pragma_Argument_Association (Loc,
Expression => Make_String_Literal (Loc, Str))))));
Set_Entity (N, Ent);
Rewrite (N, New_Occurrence_Of (Ent, Loc));
end Elab_Body;
--------------------
-- Elab_Subp_Body --
--------------------
-- Always ignored. In CodePeer mode, gnat2scil knows how to handle
-- this attribute directly, and if we are not in CodePeer mode it is
-- entirely ignored ???
when Attribute_Elab_Subp_Body =>
return;
----------------
-- Elaborated --
----------------
-- Elaborated is always True for preelaborated units, predefined units,
-- pure units and units which have Elaborate_Body pragmas. These units
-- have no elaboration entity.
-- Note: The Elaborated attribute is never passed to the back end
when Attribute_Elaborated => Elaborated : declare
Elab_Id : constant Entity_Id := Elaboration_Entity (Entity (Pref));
begin
if Present (Elab_Id) then
Rewrite (N,
Make_Op_Ne (Loc,
Left_Opnd => New_Occurrence_Of (Elab_Id, Loc),
Right_Opnd => Make_Integer_Literal (Loc, Uint_0)));
Analyze_And_Resolve (N, Typ);
else
Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
end if;
end Elaborated;
--------------
-- Enum_Rep --
--------------
when Attribute_Enum_Rep => Enum_Rep : declare
Expr : Node_Id;
begin
-- Get the expression, which is X for Enum_Type'Enum_Rep (X) or
-- X'Enum_Rep.
if Is_Non_Empty_List (Exprs) then
Expr := First (Exprs);
else
Expr := Pref;
end if;
-- If not constant-folded, Enum_Type'Enum_Rep (X) or X'Enum_Rep
-- expands to
-- target-type!(X)
-- This is an unchecked conversion from the enumeration type to the
-- target integer type, which is treated by the back end as a normal
-- integer conversion, treating the enumeration type as an integer,
-- which is exactly what we want. Unlike for the Pos attribute, we
-- cannot use a regular conversion since the associated check would
-- involve comparing the converted bounds, i.e. would involve the use
-- of 'Pos instead 'Enum_Rep for these bounds.
-- However the target type is universal integer in most cases, which
-- is a very large type, so in the case of an enumeration type, we
-- first convert to a small signed integer type in order not to lose
-- the size information.
if Is_Enumeration_Type (Ptyp) then
Rewrite (N, Unchecked_Convert_To (Get_Integer_Type (Ptyp), Expr));
Convert_To_And_Rewrite (Typ, N);
-- Deal with integer types (replace by conversion)
else
Rewrite (N, Convert_To (Typ, Expr));
end if;
Analyze_And_Resolve (N, Typ);
end Enum_Rep;
--------------
-- Enum_Val --
--------------
when Attribute_Enum_Val => Enum_Val : declare
Expr : Node_Id;
Btyp : constant Entity_Id := Base_Type (Ptyp);
begin
-- X'Enum_Val (Y) expands to
-- [constraint_error when _rep_to_pos (Y, False) = -1, msg]
-- X!(Y);
Expr := Unchecked_Convert_To (Ptyp, First (Exprs));
-- Ensure that the expression is not truncated since the "bad" bits
-- are desired.
if Nkind (Expr) = N_Unchecked_Type_Conversion then
Set_No_Truncation (Expr);
end if;
Insert_Action (N,
Make_Raise_Constraint_Error (Loc,
Condition =>
Make_Op_Eq (Loc,
Left_Opnd =>
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (TSS (Btyp, TSS_Rep_To_Pos), Loc),
Parameter_Associations => New_List (
Relocate_Node (Duplicate_Subexpr (Expr)),
New_Occurrence_Of (Standard_False, Loc))),
Right_Opnd => Make_Integer_Literal (Loc, -1)),
Reason => CE_Range_Check_Failed));
Rewrite (N, Expr);
Analyze_And_Resolve (N, Ptyp);
end Enum_Val;
--------------
-- Exponent --
--------------
-- Transforms 'Exponent into a call to the floating-point attribute
-- function Exponent in Fat_xxx (where xxx is the root type)
when Attribute_Exponent =>
Expand_Fpt_Attribute_R (N);
------------------
-- External_Tag --
------------------
-- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
when Attribute_External_Tag =>
Rewrite (N,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_External_Tag), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Tag,
Prefix => Prefix (N)))));
Analyze_And_Resolve (N, Standard_String);
-----------------------
-- Finalization_Size --
-----------------------
when Attribute_Finalization_Size => Finalization_Size : declare
function Calculate_Header_Size return Node_Id;
-- Generate a runtime call to calculate the size of the hidden header
-- along with any added padding which would precede a heap-allocated
-- object of the prefix type.
---------------------------
-- Calculate_Header_Size --
---------------------------
function Calculate_Header_Size return Node_Id is
begin
-- Generate:
-- Typ (Header_Size_With_Padding (Pref'Alignment))
return
Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Header_Size_With_Padding), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Copy_Tree (Pref),
Attribute_Name => Name_Alignment))));
end Calculate_Header_Size;
-- Local variables
Size : Entity_Id;
-- Start of processing for Finalization_Size
begin
-- An object of a class-wide type first requires a runtime check to
-- determine whether it is actually controlled or not. Depending on
-- the outcome of this check, the Finalization_Size of the object
-- may be zero or some positive value.
--
-- In this scenario, Pref'Finalization_Size is expanded into
--
-- Size : Integer := 0;
--
-- if Needs_Finalization (Pref'Tag) then
-- Size := Integer (Header_Size_With_Padding (Pref'Alignment));
-- end if;
--
-- and the attribute reference is replaced with a reference to Size.
if Is_Class_Wide_Type (Ptyp) then
Size := Make_Temporary (Loc, 'S');
Insert_Actions (N, New_List (
-- Generate:
-- Size : Integer := 0;
Make_Object_Declaration (Loc,
Defining_Identifier => Size,
Object_Definition =>
New_Occurrence_Of (Standard_Integer, Loc),
Expression => Make_Integer_Literal (Loc, 0)),
-- Generate:
-- if Needs_Finalization (Pref'Tag) then
-- Size :=
-- Integer (Header_Size_With_Padding (Pref'Alignment));
-- end if;
Make_If_Statement (Loc,
Condition =>
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Needs_Finalization), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Copy_Tree (Pref),
Attribute_Name => Name_Tag))),
Then_Statements => New_List (
Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (Size, Loc),
Expression =>
Convert_To
(Standard_Integer, Calculate_Header_Size))))));
Rewrite (N, New_Occurrence_Of (Size, Loc));
-- The prefix is known to be controlled at compile time. Calculate
-- Finalization_Size by calling function Header_Size_With_Padding.
elsif Needs_Finalization (Ptyp) then
Rewrite (N, Calculate_Header_Size);
-- The prefix is not an object with controlled parts, so its
-- Finalization_Size is zero.
else
Rewrite (N, Make_Integer_Literal (Loc, 0));
end if;
-- Due to cases where the entity type of the attribute is already
-- resolved the rewritten N must get re-resolved to its appropriate
-- type.
Analyze_And_Resolve (N, Typ);
end Finalization_Size;
-----------------
-- First, Last --
-----------------
when Attribute_First
| Attribute_Last
=>
-- If the prefix type is a constrained packed array type which
-- already has a Packed_Array_Impl_Type representation defined, then
-- replace this attribute with a direct reference to the attribute of
-- the appropriate index subtype (since otherwise the back end will
-- try to give us the value of 'First for this implementation type).
-- Do not do this if Ptyp depends on a discriminant as its bounds
-- are only available through N.
if Is_Constrained_Packed_Array (Ptyp)
and then not Size_Depends_On_Discriminant (Ptyp)
then
Rewrite (N,
Make_Attribute_Reference (Loc,
Attribute_Name => Attribute_Name (N),
Prefix =>
New_Occurrence_Of (Get_Index_Subtype (N), Loc)));
Analyze_And_Resolve (N, Typ);
-- For a constrained array type, if the bound is a reference to an
-- entity which is not a discriminant, just replace with a direct
-- reference. Note that this must be in keeping with what is done
-- for scalar types in order for range checks to be elided in loops.
-- However, avoid doing it if the array type is public because, in
-- this case, we effectively rely on the back end to create public
-- symbols with consistent names across units for the array bounds.
elsif Is_Array_Type (Ptyp)
and then Is_Constrained (Ptyp)
and then not Is_Public (Ptyp)
then
declare
Bnd : Node_Id;
begin
if Id = Attribute_First then
Bnd := Type_Low_Bound (Get_Index_Subtype (N));
else
Bnd := Type_High_Bound (Get_Index_Subtype (N));
end if;
if Is_Entity_Name (Bnd)
and then Ekind (Entity (Bnd)) /= E_Discriminant
then
Rewrite (N, New_Occurrence_Of (Entity (Bnd), Loc));
end if;
end;
-- For access type, apply access check as needed
elsif Is_Access_Type (Ptyp) then
Apply_Access_Check (N);
-- For scalar type, if the bound is a reference to an entity, just
-- replace with a direct reference. Note that we can only have a
-- reference to a constant entity at this stage, anything else would
-- have already been rewritten.
elsif Is_Scalar_Type (Ptyp) then
declare
Bnd : Node_Id;
begin
if Id = Attribute_First then
Bnd := Type_Low_Bound (Ptyp);
else
Bnd := Type_High_Bound (Ptyp);
end if;
if Is_Entity_Name (Bnd) then
Rewrite (N, New_Occurrence_Of (Entity (Bnd), Loc));
end if;
end;
end if;
---------------
-- First_Bit --
---------------
-- We leave the computation up to the back end, since we don't know what
-- layout will be chosen if no component clause was specified.
when Attribute_First_Bit =>
Apply_Universal_Integer_Attribute_Checks (N);
--------------------------------
-- Fixed_Value, Integer_Value --
--------------------------------
-- We transform
-- fixtype'Fixed_Value (integer-value)
-- inttype'Integer_Value (fixed-value)
-- into
-- fixtype (integer-value)
-- inttype (fixed-value)
-- respectively.
-- We set Conversion_OK on the conversion because we do not want it
-- to go through the fixed-point conversion circuits.
when Attribute_Fixed_Value
| Attribute_Integer_Value
=>
Rewrite (N, OK_Convert_To (Entity (Pref), First (Exprs)));
-- Note that it might appear that a properly analyzed unchecked
-- conversion would be just fine here, but that's not the case,
-- since the full range checks performed by the following calls
-- are critical.
Apply_Type_Conversion_Checks (N);
-- Note that Apply_Type_Conversion_Checks only deals with the
-- overflow checks on conversions involving fixed-point types
-- so we must apply range checks manually on them and expand.
Apply_Scalar_Range_Check
(Expression (N), Etype (N), Fixed_Int => True);
Set_Analyzed (N);
Expand (N);
-----------
-- Floor --
-----------
-- Transforms 'Floor into a call to the floating-point attribute
-- function Floor in Fat_xxx (where xxx is the root type)
when Attribute_Floor =>
Expand_Fpt_Attribute_R (N);
----------
-- Fore --
----------
-- For the fixed-point type Typ:
-- Typ'Fore
-- expands into
-- System.Fore_xx (ftyp (Typ'First), ftyp (Typ'Last) [,pm])
-- For decimal fixed-point types
-- xx = Decimal{32,64,128}
-- ftyp = Integer_{32,64,128}
-- pm = Typ'Scale
-- For the most common ordinary fixed-point types
-- xx = Fixed{32,64,128}
-- ftyp = Integer_{32,64,128}
-- pm = numerator of Typ'Small
-- denominator of Typ'Small
-- min (scale of Typ'Small, 0)
-- For other ordinary fixed-point types
-- xx = Fixed
-- ftyp = Long_Float
-- pm = none
-- Note that we know that the type is a nonstatic subtype, or Fore would
-- have been computed statically in Eval_Attribute.
when Attribute_Fore =>
declare
Arg_List : List_Id;
Fid : RE_Id;
Ftyp : Entity_Id;
begin
if Is_Decimal_Fixed_Point_Type (Ptyp) then
if Esize (Ptyp) <= 32 then
Fid := RE_Fore_Decimal32;
Ftyp := RTE (RE_Integer_32);
elsif Esize (Ptyp) <= 64 then
Fid := RE_Fore_Decimal64;
Ftyp := RTE (RE_Integer_64);
else
Fid := RE_Fore_Decimal128;
Ftyp := RTE (RE_Integer_128);
end if;
else
declare
Num : constant Uint := Norm_Num (Small_Value (Ptyp));
Den : constant Uint := Norm_Den (Small_Value (Ptyp));
Max : constant Uint := UI_Max (Num, Den);
Min : constant Uint := UI_Min (Num, Den);
Siz : constant Uint := Esize (Ptyp);
begin
if Siz <= 32
and then Max <= Uint_2 ** 31
and then (Min = Uint_1
or else Num < Den
or else Num < Uint_10 ** 8)
then
Fid := RE_Fore_Fixed32;
Ftyp := RTE (RE_Integer_32);
elsif Siz <= 64
and then Max <= Uint_2 ** 63
and then (Min = Uint_1
or else Num < Den
or else Num < Uint_10 ** 17)
then
Fid := RE_Fore_Fixed64;
Ftyp := RTE (RE_Integer_64);
elsif System_Max_Integer_Size = 128
and then Max <= Uint_2 ** 127
and then (Min = Uint_1
or else Num < Den
or else Num < Uint_10 ** 37)
then
Fid := RE_Fore_Fixed128;
Ftyp := RTE (RE_Integer_128);
else
Fid := RE_Fore_Fixed;
Ftyp := Standard_Long_Float;
end if;
end;
end if;
Arg_List := New_List (
Convert_To (Ftyp,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ptyp, Loc),
Attribute_Name => Name_First)));
Append_To (Arg_List,
Convert_To (Ftyp,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ptyp, Loc),
Attribute_Name => Name_Last)));
-- For decimal, append Scale and also set to do literal conversion
if Is_Decimal_Fixed_Point_Type (Ptyp) then
Set_Conversion_OK (First (Arg_List));
Set_Conversion_OK (Next (First (Arg_List)));
Append_To (Arg_List,
Make_Integer_Literal (Loc, Scale_Value (Ptyp)));
-- For ordinary fixed-point types, append Num, Den and Scale
-- parameters and also set to do literal conversion
elsif Fid /= RE_Fore_Fixed then
Set_Conversion_OK (First (Arg_List));
Set_Conversion_OK (Next (First (Arg_List)));
Append_To (Arg_List,
Make_Integer_Literal (Loc, -Norm_Num (Small_Value (Ptyp))));
Append_To (Arg_List,
Make_Integer_Literal (Loc, -Norm_Den (Small_Value (Ptyp))));
declare
Val : Ureal := Small_Value (Ptyp);
Scale : Int := 0;
begin
while Val >= Ureal_10 loop
Val := Val / Ureal_10;
Scale := Scale - 1;
end loop;
Append_To (Arg_List,
Make_Integer_Literal (Loc, UI_From_Int (Scale)));
end;
end if;
Rewrite (N,
Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (Fid), Loc),
Parameter_Associations => Arg_List)));
Analyze_And_Resolve (N, Typ);
end;
--------------
-- Fraction --
--------------
-- Transforms 'Fraction into a call to the floating-point attribute
-- function Fraction in Fat_xxx (where xxx is the root type)
when Attribute_Fraction =>
Expand_Fpt_Attribute_R (N);
--------------
-- From_Any --
--------------
when Attribute_From_Any => From_Any : declare
Decls : constant List_Id := New_List;
begin
Rewrite (N,
Build_From_Any_Call (Ptyp,
Relocate_Node (First (Exprs)),
Decls));
Insert_Actions (N, Decls);
Analyze_And_Resolve (N, Ptyp);
end From_Any;
----------------------
-- Has_Same_Storage --
----------------------
when Attribute_Has_Same_Storage => Has_Same_Storage : declare
Loc : constant Source_Ptr := Sloc (N);
X : constant Node_Id := Prefix (N);
Y : constant Node_Id := First (Expressions (N));
-- The arguments
X_Addr : Node_Id;
Y_Addr : Node_Id;
-- Rhe expressions for their addresses
X_Size : Node_Id;
Y_Size : Node_Id;
-- Rhe expressions for their sizes
begin
-- The attribute is expanded as:
-- (X'address = Y'address)
-- and then (X'Size = Y'Size)
-- and then (X'Size /= 0) (AI12-0077)
-- If both arguments have the same Etype the second conjunct can be
-- omitted.
X_Addr :=
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => New_Copy_Tree (X));
Y_Addr :=
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => New_Copy_Tree (Y));
X_Size :=
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Size,
Prefix => New_Copy_Tree (X));
if Etype (X) = Etype (Y) then
Rewrite (N,
Make_And_Then (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd => X_Addr,
Right_Opnd => Y_Addr),
Right_Opnd =>
Make_Op_Ne (Loc,
Left_Opnd => X_Size,
Right_Opnd => Make_Integer_Literal (Loc, 0))));
else
Y_Size :=
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Size,
Prefix => New_Copy_Tree (Y));
Rewrite (N,
Make_And_Then (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd => X_Addr,
Right_Opnd => Y_Addr),
Right_Opnd =>
Make_And_Then (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd => X_Size,
Right_Opnd => Y_Size),
Right_Opnd =>
Make_Op_Ne (Loc,
Left_Opnd => New_Copy_Tree (X_Size),
Right_Opnd => Make_Integer_Literal (Loc, 0)))));
end if;
Analyze_And_Resolve (N, Standard_Boolean);
end Has_Same_Storage;
--------------
-- Identity --
--------------
-- For an exception returns a reference to the exception data:
-- Exception_Id!(Prefix'Reference)
-- For a task it returns a reference to the _task_id component of
-- corresponding record:
-- taskV!(Prefix)._Task_Id, converted to the type Task_Id defined
-- in Ada.Task_Identification
when Attribute_Identity => Identity : declare
Id_Kind : Entity_Id;
begin
if Ptyp = Standard_Exception_Type then
Id_Kind := RTE (RE_Exception_Id);
if Present (Renamed_Entity (Entity (Pref))) then
Set_Entity (Pref, Renamed_Entity (Entity (Pref)));
end if;
Rewrite (N,
Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref)));
else
Id_Kind := RTE (RO_AT_Task_Id);
-- If the prefix is a task interface, the Task_Id is obtained
-- dynamically through a dispatching call, as for other task
-- attributes applied to interfaces.
if Ada_Version >= Ada_2005
and then Ekind (Ptyp) = E_Class_Wide_Type
and then Is_Interface (Ptyp)
and then Is_Task_Interface (Ptyp)
then
Rewrite (N,
Unchecked_Convert_To
(Id_Kind, Build_Disp_Get_Task_Id_Call (Pref)));
else
Rewrite (N,
Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
end if;
end if;
Analyze_And_Resolve (N, Id_Kind);
end Identity;
-----------
-- Image --
-----------
when Attribute_Image =>
-- Leave attribute unexpanded in CodePeer mode: the gnat2scil
-- back-end knows how to handle this attribute directly.
if CodePeer_Mode then
return;
end if;
Exp_Imgv.Expand_Image_Attribute (N);
---------
-- Img --
---------
-- X'Img is expanded to typ'Image (X), where typ is the type of X
when Attribute_Img =>
Exp_Imgv.Expand_Image_Attribute (N);
-----------------
-- Initialized --
-----------------
-- For execution, we could either implement an approximation of this
-- aspect, or use Valid_Scalars as a first approximation. For now we do
-- the latter.
when Attribute_Initialized =>
-- Do not expand 'Initialized in CodePeer mode, it will be handled
-- by the back-end directly.
if CodePeer_Mode then
return;
end if;
Rewrite
(N,
Make_Attribute_Reference
(Sloc => Loc,
Prefix => Pref,
Attribute_Name => Name_Valid_Scalars,
Expressions => Exprs));
Analyze_And_Resolve (N);
-----------
-- Input --
-----------
when Attribute_Input => Input : declare
P_Type : constant Entity_Id := Entity (Pref);
B_Type : constant Entity_Id := Base_Type (P_Type);
U_Type : constant Entity_Id := Underlying_Type (P_Type);
Strm : constant Node_Id := First (Exprs);
Fname : Entity_Id;
Decl : Node_Id;
Call : Node_Id;
Prag : Node_Id;
Arg2 : Node_Id;
Rfunc : Node_Id;
Cntrl : Node_Id := Empty;
-- Value for controlling argument in call. Always Empty except in
-- the dispatching (class-wide type) case, where it is a reference
-- to the dummy object initialized to the right internal tag.
procedure Freeze_Stream_Subprogram (F : Entity_Id);
-- The expansion of the attribute reference may generate a call to
-- a user-defined stream subprogram that is frozen by the call. This
-- can lead to access-before-elaboration problem if the reference
-- appears in an object declaration and the subprogram body has not
-- been seen. The freezing of the subprogram requires special code
-- because it appears in an expanded context where expressions do
-- not freeze their constituents.
------------------------------
-- Freeze_Stream_Subprogram --
------------------------------
procedure Freeze_Stream_Subprogram (F : Entity_Id) is
Decl : constant Node_Id := Unit_Declaration_Node (F);
Bod : Node_Id;
begin
-- If this is user-defined subprogram, the corresponding
-- stream function appears as a renaming-as-body, and the
-- user subprogram must be retrieved by tree traversal.
if Present (Decl)
and then Nkind (Decl) = N_Subprogram_Declaration
and then Present (Corresponding_Body (Decl))
then
Bod := Corresponding_Body (Decl);
if Nkind (Unit_Declaration_Node (Bod)) =
N_Subprogram_Renaming_Declaration
then
Set_Is_Frozen (Entity (Name (Unit_Declaration_Node (Bod))));
end if;
end if;
end Freeze_Stream_Subprogram;
-- Start of processing for Input
begin
-- If no underlying type, we have an error that will be diagnosed
-- elsewhere, so here we just completely ignore the expansion.
if No (U_Type) then
return;
end if;
-- Stream operations can appear in user code even if the restriction
-- No_Streams is active (for example, when instantiating a predefined
-- container). In that case rewrite the attribute as a Raise to
-- prevent any run-time use.
if Restriction_Active (No_Streams) then
Rewrite (N,
Make_Raise_Program_Error (Sloc (N),
Reason => PE_Stream_Operation_Not_Allowed));
Set_Etype (N, B_Type);
return;
end if;
-- If there is a TSS for Input, just call it
Fname := Find_Stream_Subprogram (P_Type, TSS_Stream_Input);
if Present (Fname) then
null;
else
-- If there is a Stream_Convert pragma, use it, we rewrite
-- sourcetyp'Input (stream)
-- as
-- sourcetyp (streamread (strmtyp'Input (stream)));
-- where streamread is the given Read function that converts an
-- argument of type strmtyp to type sourcetyp or a type from which
-- it is derived (extra conversion required for the derived case).
Prag := Get_Stream_Convert_Pragma (P_Type);
if Present (Prag) then
Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
Rfunc := Entity (Expression (Arg2));
Rewrite (N,
Convert_To (B_Type,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Rfunc, Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of
(Etype (First_Formal (Rfunc)), Loc),
Attribute_Name => Name_Input,
Expressions => Exprs)))));
Analyze_And_Resolve (N, B_Type);
return;
-- Limited types
elsif Default_Streaming_Unavailable (U_Type) then
-- Do the same thing here as is done above in the
-- case where a No_Streams restriction is active.
Rewrite (N,
Make_Raise_Program_Error (Sloc (N),
Reason => PE_Stream_Operation_Not_Allowed));
Set_Etype (N, B_Type);
return;
-- Elementary types
elsif Is_Elementary_Type (U_Type) then
-- A special case arises if we have a defined _Read routine,
-- since in this case we are required to call this routine.
if Present (Find_Inherited_TSS (P_Type, TSS_Stream_Read)) then
Build_Record_Or_Elementary_Input_Function
(Loc, P_Type, Decl, Fname);
Insert_Action (N, Decl);
-- For normal cases, we call the I_xxx routine directly
else
Rewrite (N, Build_Elementary_Input_Call (N));
Analyze_And_Resolve (N, P_Type);
return;
end if;
-- Array type case
elsif Is_Array_Type (U_Type) then
Build_Array_Input_Function (Loc, U_Type, Decl, Fname);
Compile_Stream_Body_In_Scope (N, Decl, U_Type);
-- Dispatching case with class-wide type
elsif Is_Class_Wide_Type (P_Type) then
-- No need to do anything else compiling under restriction
-- No_Dispatching_Calls. During the semantic analysis we
-- already notified such violation.
if Restriction_Active (No_Dispatching_Calls) then
return;
end if;
declare
Rtyp : constant Entity_Id := Root_Type (P_Type);
Expr : Node_Id; -- call to Descendant_Tag
Get_Tag : Node_Id; -- expression to read the 'Tag
begin
-- Read the internal tag (RM 13.13.2(34)) and use it to
-- initialize a dummy tag value. We used to unconditionally
-- generate:
--
-- Descendant_Tag (String'Input (Strm), P_Type);
--
-- which turns into a call to String_Input_Blk_IO. However,
-- if the input is malformed, that could try to read an
-- enormous String, causing chaos. So instead we call
-- String_Input_Tag, which does the same thing as
-- String_Input_Blk_IO, except that if the String is
-- absurdly long, it raises an exception.
--
-- However, if the No_Stream_Optimizations restriction
-- is active, we disable this unnecessary attempt at
-- robustness; we really need to read the string
-- character-by-character.
--
-- This value is used only to provide a controlling
-- argument for the eventual _Input call. Descendant_Tag is
-- called rather than Internal_Tag to ensure that we have a
-- tag for a type that is descended from the prefix type and
-- declared at the same accessibility level (the exception
-- Tag_Error will be raised otherwise). The level check is
-- required for Ada 2005 because tagged types can be
-- extended in nested scopes (AI-344).
-- Note: we used to generate an explicit declaration of a
-- constant Ada.Tags.Tag object, and use an occurrence of
-- this constant in Cntrl, but this caused a secondary stack
-- leak.
if Restriction_Active (No_Stream_Optimizations) then
Get_Tag :=
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Standard_String, Loc),
Attribute_Name => Name_Input,
Expressions => New_List (
Relocate_Node (Duplicate_Subexpr (Strm))));
else
Get_Tag :=
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of
(RTE (RE_String_Input_Tag), Loc),
Parameter_Associations => New_List (
Relocate_Node (Duplicate_Subexpr (Strm))));
end if;
Expr :=
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Descendant_Tag), Loc),
Parameter_Associations => New_List (
Get_Tag,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (P_Type, Loc),
Attribute_Name => Name_Tag)));
Set_Etype (Expr, RTE (RE_Tag));
-- Now we need to get the entity for the call, and construct
-- a function call node, where we preset a reference to Dnn
-- as the controlling argument (doing an unchecked convert
-- to the class-wide tagged type to make it look like a real
-- tagged object).
Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input);
Cntrl := Unchecked_Convert_To (P_Type, Expr);
Set_Etype (Cntrl, P_Type);
Set_Parent (Cntrl, N);
end;
-- For tagged types, use the primitive Input function
elsif Is_Tagged_Type (U_Type) then
Fname := Find_Prim_Op (U_Type, TSS_Stream_Input);
-- All other record type cases, including protected records. The
-- latter only arise for expander generated code for handling
-- shared passive partition access.
else
pragma Assert
(Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
-- Ada 2005 (AI-216): Program_Error is raised executing default
-- implementation of the Input attribute of an unchecked union
-- type if the type lacks default discriminant values.
if Is_Unchecked_Union (Base_Type (U_Type))
and then
No (Discriminant_Default_Value (First_Discriminant (U_Type)))
then
Rewrite (N,
Make_Raise_Program_Error (Loc,
Reason => PE_Unchecked_Union_Restriction));
Set_Etype (N, B_Type);
return;
end if;
-- Build the type's Input function, passing the subtype rather
-- than its base type, because checks are needed in the case of
-- constrained discriminants (see Ada 2012 AI05-0192).
Build_Record_Or_Elementary_Input_Function
(Loc, U_Type, Decl, Fname);
Insert_Action (N, Decl);
if Nkind (Parent (N)) = N_Object_Declaration
and then Is_Record_Type (U_Type)
then
-- The stream function may contain calls to user-defined
-- Read procedures for individual components.
declare
Comp : Entity_Id;
Func : Entity_Id;
begin
Comp := First_Component (U_Type);
while Present (Comp) loop
Func :=
Find_Stream_Subprogram
(Etype (Comp), TSS_Stream_Read);
if Present (Func) then
Freeze_Stream_Subprogram (Func);
end if;
Next_Component (Comp);
end loop;
end;
end if;
end if;
end if;
-- If we fall through, Fname is the function to be called. The result
-- is obtained by calling the appropriate function, then converting
-- the result. The conversion does a subtype check.
Call :=
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Fname, Loc),
Parameter_Associations => New_List (
Relocate_Node (Strm)));
Set_Controlling_Argument (Call, Cntrl);
Rewrite (N, Unchecked_Convert_To (P_Type, Call));
Analyze_And_Resolve (N, P_Type);
if Nkind (Parent (N)) = N_Object_Declaration then
Freeze_Stream_Subprogram (Fname);
end if;
end Input;
-------------------
-- Invalid_Value --
-------------------
when Attribute_Invalid_Value =>
Rewrite (N, Get_Simple_Init_Val (Ptyp, N));
-- The value produced may be a conversion of a literal, which must be
-- resolved to establish its proper type.
Analyze_And_Resolve (N);
--------------
-- Last_Bit --
--------------
-- We leave the computation up to the back end, since we don't know what
-- layout will be chosen if no component clause was specified.
when Attribute_Last_Bit =>
Apply_Universal_Integer_Attribute_Checks (N);
------------------
-- Leading_Part --
------------------
-- Transforms 'Leading_Part into a call to the floating-point attribute
-- function Leading_Part in Fat_xxx (where xxx is the root type)
-- Note: strictly, we should generate special case code to deal with
-- absurdly large positive arguments (greater than Integer'Last), which
-- result in returning the first argument unchanged, but it hardly seems
-- worth the effort. We raise constraint error for absurdly negative
-- arguments which is fine.
when Attribute_Leading_Part =>
Expand_Fpt_Attribute_RI (N);
------------
-- Length --
------------
when Attribute_Length => Length : declare
Ityp : Entity_Id;
Xnum : Uint;
begin
-- Processing for packed array types
if Is_Packed_Array (Ptyp) then
Ityp := Get_Index_Subtype (N);
-- If the index type, Ityp, is an enumeration type with holes,
-- then we calculate X'Length explicitly using
-- Typ'Max
-- (0, Ityp'Pos (X'Last (N)) -
-- Ityp'Pos (X'First (N)) + 1);
-- Since the bounds in the template are the representation values
-- and the back end would get the wrong value.
if Is_Enumeration_Type (Ityp)
and then Present (Enum_Pos_To_Rep (Base_Type (Ityp)))
then
if No (Exprs) then
Xnum := Uint_1;
else
Xnum := Expr_Value (First (Expressions (N)));
end if;
Rewrite (N,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Typ, Loc),
Attribute_Name => Name_Max,
Expressions => New_List
(Make_Integer_Literal (Loc, 0),
Make_Op_Add (Loc,
Left_Opnd =>
Make_Op_Subtract (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ityp, Loc),
Attribute_Name => Name_Pos,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix => Duplicate_Subexpr (Pref),
Attribute_Name => Name_Last,
Expressions => New_List (
Make_Integer_Literal (Loc, Xnum))))),
Right_Opnd =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ityp, Loc),
Attribute_Name => Name_Pos,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
Duplicate_Subexpr_No_Checks (Pref),
Attribute_Name => Name_First,
Expressions => New_List (
Make_Integer_Literal (Loc, Xnum)))))),
Right_Opnd => Make_Integer_Literal (Loc, 1)))));
Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
return;
-- If the prefix type is a constrained packed array type which
-- already has a Packed_Array_Impl_Type representation defined,
-- then replace this attribute with a reference to 'Range_Length
-- of the appropriate index subtype (since otherwise the
-- back end will try to give us the value of 'Length for
-- this implementation type).s
elsif Is_Constrained (Ptyp) then
Rewrite (N,
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Range_Length,
Prefix => New_Occurrence_Of (Ityp, Loc)));
Analyze_And_Resolve (N, Typ);
end if;
-- Access type case
elsif Is_Access_Type (Ptyp) then
Apply_Access_Check (N);
-- If the designated type is a packed array type, then we convert
-- the reference to:
-- typ'Max (0, 1 +
-- xtyp'Pos (Pref'Last (Expr)) -
-- xtyp'Pos (Pref'First (Expr)));
-- This is a bit complex, but it is the easiest thing to do that
-- works in all cases including enum types with holes xtyp here
-- is the appropriate index type.
declare
Dtyp : constant Entity_Id := Designated_Type (Ptyp);
Xtyp : Entity_Id;
begin
if Is_Packed_Array (Dtyp) then
Xtyp := Get_Index_Subtype (N);
Rewrite (N,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Typ, Loc),
Attribute_Name => Name_Max,
Expressions => New_List (
Make_Integer_Literal (Loc, 0),
Make_Op_Add (Loc,
Make_Integer_Literal (Loc, 1),
Make_Op_Subtract (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Xtyp, Loc),
Attribute_Name => Name_Pos,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix => Duplicate_Subexpr (Pref),
Attribute_Name => Name_Last,
Expressions =>
New_Copy_List (Exprs)))),
Right_Opnd =>
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Xtyp, Loc),
Attribute_Name => Name_Pos,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
Duplicate_Subexpr_No_Checks (Pref),
Attribute_Name => Name_First,
Expressions =>
New_Copy_List (Exprs)))))))));
Analyze_And_Resolve (N, Typ);
end if;
end;
-- Otherwise leave it to the back end
else
Apply_Universal_Integer_Attribute_Checks (N);
end if;
end Length;
-- Attribute Loop_Entry is replaced with a reference to a constant value
-- which captures the prefix at the entry point of the related loop. The
-- loop itself may be transformed into a conditional block.
when Attribute_Loop_Entry =>
Expand_Loop_Entry_Attribute (N);
-------------
-- Machine --
-------------
-- Transforms 'Machine into a call to the floating-point attribute
-- function Machine in Fat_xxx (where xxx is the root type).
-- Expansion is avoided for cases the back end can handle directly.
when Attribute_Machine =>
if not Is_Inline_Floating_Point_Attribute (N) then
Expand_Fpt_Attribute_R (N);
end if;
----------------------
-- Machine_Rounding --
----------------------
-- Transforms 'Machine_Rounding into a call to the floating-point
-- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
-- type). Expansion is avoided for cases the back end can handle
-- directly.
when Attribute_Machine_Rounding =>
if not Is_Inline_Floating_Point_Attribute (N) then
Expand_Fpt_Attribute_R (N);
end if;
------------------
-- Machine_Size --
------------------
-- Machine_Size is equivalent to Object_Size, so transform it into
-- Object_Size and that way the back end never sees Machine_Size.
when Attribute_Machine_Size =>
Rewrite (N,
Make_Attribute_Reference (Loc,
Prefix => Prefix (N),
Attribute_Name => Name_Object_Size));
Analyze_And_Resolve (N, Typ);
--------------
-- Mantissa --
--------------
-- The only case that can get this far is the dynamic case of the old
-- Ada 83 Mantissa attribute for the fixed-point case. For this case,
-- we expand:
-- typ'Mantissa
-- into
-- ityp (System.Mantissa.Mantissa_Value
-- (Integer'Integer_Value (typ'First),
-- Integer'Integer_Value (typ'Last)));
when Attribute_Mantissa =>
Rewrite (N,
Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Standard_Integer, Loc),
Attribute_Name => Name_Integer_Value,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ptyp, Loc),
Attribute_Name => Name_First))),
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Standard_Integer, Loc),
Attribute_Name => Name_Integer_Value,
Expressions => New_List (
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ptyp, Loc),
Attribute_Name => Name_Last)))))));
Analyze_And_Resolve (N, Typ);
---------
-- Max --
---------
when Attribute_Max =>
Expand_Min_Max_Attribute (N);
----------------------------------
-- Max_Size_In_Storage_Elements --
----------------------------------
when Attribute_Max_Size_In_Storage_Elements => declare
Typ : constant Entity_Id := Etype (N);
begin
-- If the prefix is X'Class, we transform it into a direct reference
-- to the class-wide type, because the back end must not see a 'Class
-- reference. See also 'Size.
if Is_Entity_Name (Pref)
and then Is_Class_Wide_Type (Entity (Pref))
then
Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
return;
end if;
-- Heap-allocated controlled objects contain two extra pointers which
-- are not part of the actual type. Transform the attribute reference
-- into a runtime expression to add the size of the hidden header.
if Needs_Finalization (Ptyp) and then not Header_Size_Added (N) then
Set_Header_Size_Added (N);
-- Generate:
-- P'Max_Size_In_Storage_Elements +
-- Typ (Header_Size_With_Padding (Ptyp'Alignment))
Rewrite (N,
Make_Op_Add (Loc,
Left_Opnd => Relocate_Node (N),
Right_Opnd =>
Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of
(RTE (RE_Header_Size_With_Padding), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Ptyp, Loc),
Attribute_Name => Name_Alignment))))));
Analyze_And_Resolve (N, Typ);
return;
end if;
-- In the other cases apply the required checks
Apply_Universal_Integer_Attribute_Checks (N);
end;
--------------------
-- Mechanism_Code --
--------------------
when Attribute_Mechanism_Code =>
-- We must replace the prefix in the renamed case
if Is_Entity_Name (Pref)
and then Present (Alias (Entity (Pref)))
then
Set_Renamed_Subprogram (Pref, Alias (Entity (Pref)));
end if;
---------
-- Min --
---------
when Attribute_Min =>
Expand_Min_Max_Attribute (N);
---------
-- Mod --
---------
when Attribute_Mod => Mod_Case : declare
Arg : constant Node_Id := Relocate_Node (First (Exprs));
Hi : constant Node_Id := Type_High_Bound (Base_Type (Etype (Arg)));
Modv : constant Uint := Modulus (Btyp);
begin
-- This is not so simple. The issue is what type to use for the
-- computation of the modular value. In addition we need to use
-- the base type as above to retrieve a static bound for the
-- comparisons that follow.
-- The easy case is when the modulus value is within the bounds
-- of the signed integer type of the argument. In this case we can
-- just do the computation in that signed integer type, and then
-- do an ordinary conversion to the target type.
if Modv <= Expr_Value (Hi) then
Rewrite (N,
Convert_To (Btyp,
Make_Op_Mod (Loc,
Left_Opnd => Arg,
Right_Opnd => Make_Integer_Literal (Loc, Modv))));
-- Here we know that the modulus is larger than type'Last of the
-- integer type. There are two cases to consider:
-- a) The integer value is non-negative. In this case, it is
-- returned as the result (since it is less than the modulus).
-- b) The integer value is negative. In this case, we know that the
-- result is modulus + value, where the value might be as small as
-- -modulus. The trouble is what type do we use to do the subtract.
-- No type will do, since modulus can be as big as 2**128, and no
-- integer type accommodates this value. Let's do bit of algebra
-- modulus + value
-- = modulus - (-value)
-- = (modulus - 1) - (-value - 1)
-- Now modulus - 1 is certainly in range of the modular type.
-- -value is in the range 1 .. modulus, so -value -1 is in the
-- range 0 .. modulus-1 which is in range of the modular type.
-- Furthermore, (-value - 1) can be expressed as -(value + 1)
-- which we can compute using the integer base type.
-- Once this is done we analyze the if expression without range
-- checks, because we know everything is in range, and we want
-- to prevent spurious warnings on either branch.
else
Rewrite (N,
Make_If_Expression (Loc,
Expressions => New_List (
Make_Op_Ge (Loc,
Left_Opnd => Duplicate_Subexpr (Arg),
Right_Opnd => Make_Integer_Literal (Loc, 0)),
Convert_To (Btyp,
Duplicate_Subexpr_No_Checks (Arg)),
Make_Op_Subtract (Loc,
Left_Opnd =>
Make_Integer_Literal (Loc,
Intval => Modv - 1),
Right_Opnd =>
Convert_To (Btyp,
Make_Op_Minus (Loc,
Right_Opnd =>
Make_Op_Add (Loc,
Left_Opnd => Duplicate_Subexpr_No_Checks (Arg),
Right_Opnd =>
Make_Integer_Literal (Loc,
Intval => 1))))))));
end if;
Analyze_And_Resolve (N, Btyp, Suppress => All_Checks);
end Mod_Case;
-----------
-- Model --
-----------
-- Transforms 'Model into a call to the floating-point attribute
-- function Model in Fat_xxx (where xxx is the root type).
-- Expansion is avoided for cases the back end can handle directly.
when Attribute_Model =>
if not Is_Inline_Floating_Point_Attribute (N) then
Expand_Fpt_Attribute_R (N);
end if;
-----------------
-- Object_Size --
-----------------
-- The processing for Object_Size shares the processing for Size
---------
-- Old --
---------
when Attribute_Old => Old : declare
Typ : constant Entity_Id := Etype (N);
CW_Temp : Entity_Id;
CW_Typ : Entity_Id;
Decl : Node_Id;
Ins_Nod : Node_Id;
Subp : Node_Id;
Temp : Entity_Id;
use Old_Attr_Util.Conditional_Evaluation;
use Old_Attr_Util.Indirect_Temps;
begin
-- Generating C code we don't need to expand this attribute when
-- we are analyzing the internally built nested postconditions
-- procedure since it will be expanded inline (and later it will
-- be removed by Expand_N_Subprogram_Body). It this expansion is
-- performed in such case then the compiler generates unreferenced
-- extra temporaries.
if Modify_Tree_For_C
and then Chars (Current_Scope) = Name_uPostconditions
then
return;
end if;
-- Climb the parent chain looking for subprogram _Postconditions
Subp := N;
while Present (Subp) loop
exit when Nkind (Subp) = N_Subprogram_Body
and then Chars (Defining_Entity (Subp)) = Name_uPostconditions;
-- If assertions are disabled, no need to create the declaration
-- that preserves the value. The postcondition pragma in which
-- 'Old appears will be checked or disabled according to the
-- current policy in effect.
if Nkind (Subp) = N_Pragma and then not Is_Checked (Subp) then
return;
end if;
Subp := Parent (Subp);
end loop;
-- 'Old can only appear in a postcondition, the generated body of
-- _Postconditions must be in the tree (or inlined if we are
-- generating C code).
pragma Assert
(Present (Subp)
or else (Modify_Tree_For_C and then In_Inlined_Body));
Temp := Make_Temporary (Loc, 'T', Pref);
-- Set the entity kind now in order to mark the temporary as a
-- handler of attribute 'Old's prefix.
Mutate_Ekind (Temp, E_Constant);
Set_Stores_Attribute_Old_Prefix (Temp);
-- Push the scope of the related subprogram where _Postcondition
-- resides as this ensures that the object will be analyzed in the
-- proper context.
if Present (Subp) then
Push_Scope (Scope (Defining_Entity (Subp)));
-- No need to push the scope when generating C code since the
-- _Postcondition procedure has been inlined.
else pragma Assert (Modify_Tree_For_C);
pragma Assert (In_Inlined_Body);
null;
end if;
-- Locate the insertion place of the internal temporary that saves
-- the 'Old value.
if Present (Subp) then
Ins_Nod := Subp;
-- Generating C, the postcondition procedure has been inlined and the
-- temporary is added before the first declaration of the enclosing
-- subprogram.
else pragma Assert (Modify_Tree_For_C);
Ins_Nod := N;
while Nkind (Ins_Nod) /= N_Subprogram_Body loop
Ins_Nod := Parent (Ins_Nod);
end loop;
Ins_Nod := First (Declarations (Ins_Nod));
end if;
if Eligible_For_Conditional_Evaluation (N) then
declare
Eval_Stmts : constant List_Id := New_List;
procedure Append_For_Indirect_Temp
(N : Node_Id; Is_Eval_Stmt : Boolean);
-- Append either a declaration (which is to be elaborated
-- unconditionally) or an evaluation statement (which is
-- to be executed conditionally).
-------------------------------
-- Append_For_Indirect_Temp --
-------------------------------
procedure Append_For_Indirect_Temp
(N : Node_Id; Is_Eval_Stmt : Boolean)
is
begin
if Is_Eval_Stmt then
Append_To (Eval_Stmts, N);
else
Insert_Before_And_Analyze (Ins_Nod, N);
end if;
end Append_For_Indirect_Temp;
procedure Declare_Indirect_Temporary is new
Declare_Indirect_Temp
(Append_Item => Append_For_Indirect_Temp);
begin
Declare_Indirect_Temporary
(Attr_Prefix => Pref, Indirect_Temp => Temp);
Insert_Before_And_Analyze (
Ins_Nod,
Make_If_Statement
(Sloc => Loc,
Condition => Conditional_Evaluation_Condition (N),
Then_Statements => Eval_Stmts));
Rewrite (N, Indirect_Temp_Value
(Temp => Temp,
Typ => Etype (Pref),
Loc => Loc));
if Present (Subp) then
Pop_Scope;
end if;
return;
end;
-- Preserve the tag of the prefix by offering a specific view of the
-- class-wide version of the prefix.
elsif Is_Tagged_Type (Typ) then
-- Generate:
-- CW_Temp : constant Typ'Class := Typ'Class (Pref);
CW_Temp := Make_Temporary (Loc, 'T');
CW_Typ := Class_Wide_Type (Typ);
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => CW_Temp,
Constant_Present => True,
Object_Definition => New_Occurrence_Of (CW_Typ, Loc),
Expression =>
Convert_To (CW_Typ, Relocate_Node (Pref)));
Insert_Before_And_Analyze (Ins_Nod, Decl);
-- Generate:
-- Temp : Typ renames Typ (CW_Temp);
Insert_Before_And_Analyze (Ins_Nod,
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier => Temp,
Subtype_Mark => New_Occurrence_Of (Typ, Loc),
Name =>
Convert_To (Typ, New_Occurrence_Of (CW_Temp, Loc))));
Set_Stores_Attribute_Old_Prefix (CW_Temp);
-- Non-tagged case
else
-- Generate:
-- Temp : constant Typ := Pref;
Decl :=
Make_Object_Declaration (Loc,
Defining_Identifier => Temp,
Constant_Present => True,
Object_Definition => New_Occurrence_Of (Typ, Loc),
Expression => Relocate_Node (Pref));
Insert_Before_And_Analyze (Ins_Nod, Decl);
end if;
if Present (Subp) then
Pop_Scope;
end if;
-- Ensure that the prefix of attribute 'Old is valid. The check must
-- be inserted after the expansion of the attribute has taken place
-- to reflect the new placement of the prefix.
if Validity_Checks_On and then Validity_Check_Operands then
Ensure_Valid (Expression (Decl));
end if;
Rewrite (N, New_Occurrence_Of (Temp, Loc));
end Old;
----------------------
-- Overlaps_Storage --
----------------------
when Attribute_Overlaps_Storage => Overlaps_Storage : declare
Loc : constant Source_Ptr := Sloc (N);
X : constant Node_Id := Prefix (N);
Y : constant Node_Id := First (Expressions (N));
-- The arguments
X_Addr, Y_Addr : Node_Id;
-- The expressions for their integer addresses
X_Size, Y_Size : Node_Id;
-- The expressions for their sizes
Cond : Node_Id;
begin
-- Attribute expands into:
-- (if X'Size = 0 or else Y'Size = 0 then
-- False
-- else
-- (if X'Address <= Y'Address then
-- (X'Address + X'Size - 1) >= Y'Address
-- else
-- (Y'Address + Y'Size - 1) >= X'Address))
-- with the proper address operations. We convert addresses to
-- integer addresses to use predefined arithmetic. The size is
-- expressed in storage units. We add copies of X_Addr and Y_Addr
-- to prevent the appearance of the same node in two places in
-- the tree.
X_Addr :=
Unchecked_Convert_To (RTE (RE_Integer_Address),
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => New_Copy_Tree (X)));
Y_Addr :=
Unchecked_Convert_To (RTE (RE_Integer_Address),
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Address,
Prefix => New_Copy_Tree (Y)));
X_Size :=
Make_Op_Divide (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Size,
Prefix => New_Copy_Tree (X)),
Right_Opnd =>
Make_Integer_Literal (Loc, System_Storage_Unit));
Y_Size :=
Make_Op_Divide (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Size,
Prefix => New_Copy_Tree (Y)),
Right_Opnd =>
Make_Integer_Literal (Loc, System_Storage_Unit));
Cond :=
Make_Op_Le (Loc,
Left_Opnd => X_Addr,
Right_Opnd => Y_Addr);
-- Perform the rewriting
Rewrite (N,
Make_If_Expression (Loc, New_List (
-- Generate a check for zero-sized things like a null record with
-- size zero or an array with zero length since they have no
-- opportunity of overlapping.
-- Without this check, a zero-sized object can trigger a false
-- runtime result if it's compared against another object in
-- its declarative region, due to the zero-sized object having
-- the same address.
Make_Or_Else (Loc,
Left_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Size,
Prefix => New_Copy_Tree (X)),
Right_Opnd => Make_Integer_Literal (Loc, 0)),
Right_Opnd =>
Make_Op_Eq (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Size,
Prefix => New_Copy_Tree (Y)),
Right_Opnd => Make_Integer_Literal (Loc, 0))),
New_Occurrence_Of (Standard_False, Loc),
-- Non-zero-size overlap check
Make_If_Expression (Loc, New_List (
Cond,
Make_Op_Ge (Loc,
Left_Opnd =>
Make_Op_Add (Loc,
Left_Opnd => New_Copy_Tree (X_Addr),
Right_Opnd =>
Make_Op_Subtract (Loc,
Left_Opnd => X_Size,
Right_Opnd => Make_Integer_Literal (Loc, 1))),
Right_Opnd => Y_Addr),
Make_Op_Ge (Loc,
Left_Opnd =>
Make_Op_Add (Loc,
Left_Opnd => New_Copy_Tree (Y_Addr),
Right_Opnd =>
Make_Op_Subtract (Loc,
Left_Opnd => Y_Size,
Right_Opnd => Make_Integer_Literal (Loc, 1))),
Right_Opnd => X_Addr))))));
Analyze_And_Resolve (N, Standard_Boolean);
end Overlaps_Storage;
------------
-- Output --
------------
when Attribute_Output => Output : declare
P_Type : constant Entity_Id := Entity (Pref);
U_Type : constant Entity_Id := Underlying_Type (P_Type);
Pname : Entity_Id;
Decl : Node_Id;
Prag : Node_Id;
Arg3 : Node_Id;
Wfunc : Node_Id;
begin
-- If no underlying type, we have an error that will be diagnosed
-- elsewhere, so here we just completely ignore the expansion.
if No (U_Type) then
return;
end if;
-- Stream operations can appear in user code even if the restriction
-- No_Streams is active (for example, when instantiating a predefined
-- container). In that case rewrite the attribute as a Raise to
-- prevent any run-time use.
if Restriction_Active (No_Streams) then
Rewrite (N,
Make_Raise_Program_Error (Sloc (N),
Reason => PE_Stream_Operation_Not_Allowed));
Set_Etype (N, Standard_Void_Type);
return;
end if;
-- If TSS for Output is present, just call it
Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output);
if Present (Pname) then
null;
else
-- If there is a Stream_Convert pragma, use it, we rewrite
-- sourcetyp'Output (stream, Item)
-- as
-- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
-- where strmwrite is the given Write function that converts an
-- argument of type sourcetyp or a type acctyp, from which it is
-- derived to type strmtyp. The conversion to acttyp is required
-- for the derived case.
Prag := Get_Stream_Convert_Pragma (P_Type);
if Present (Prag) then
Arg3 :=
Next (Next (First (Pragma_Argument_Associations (Prag))));
Wfunc := Entity (Expression (Arg3));
Rewrite (N,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
Attribute_Name => Name_Output,
Expressions => New_List (
Relocate_Node (First (Exprs)),
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Wfunc, Loc),
Parameter_Associations => New_List (
OK_Convert_To (Etype (First_Formal (Wfunc)),
Relocate_Node (Next (First (Exprs)))))))));
Analyze (N);
return;
-- Limited types
elsif Default_Streaming_Unavailable (U_Type) then
-- Do the same thing here as is done above in the
-- case where a No_Streams restriction is active.
Rewrite (N,
Make_Raise_Program_Error (Sloc (N),
Reason => PE_Stream_Operation_Not_Allowed));
Set_Etype (N, Standard_Void_Type);
return;
-- For elementary types, we call the W_xxx routine directly. Note
-- that the effect of Write and Output is identical for the case
-- of an elementary type (there are no discriminants or bounds).
elsif Is_Elementary_Type (U_Type) then
-- A special case arises if we have a defined _Write routine,
-- since in this case we are required to call this routine.
if Present (Find_Inherited_TSS (P_Type, TSS_Stream_Write)) then
Build_Record_Or_Elementary_Output_Procedure
(Loc, P_Type, Decl, Pname);
Insert_Action (N, Decl);
-- For normal cases, we call the W_xxx routine directly
else
Rewrite (N, Build_Elementary_Write_Call (N));
Analyze (N);
return;
end if;
-- Array type case
elsif Is_Array_Type (U_Type) then
Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname);
Compile_Stream_Body_In_Scope (N, Decl, U_Type);
-- Class-wide case, first output external tag, then dispatch
-- to the appropriate primitive Output function (RM 13.13.2(31)).
elsif Is_Class_Wide_Type (P_Type) then
-- No need to do anything else compiling under restriction
-- No_Dispatching_Calls. During the semantic analysis we
-- already notified such violation.
if Restriction_Active (No_Dispatching_Calls) then
return;
end if;
Tag_Write : declare
Strm : constant Node_Id := First (Exprs);
Item : constant Node_Id := Next (Strm);
begin
-- Ada 2005 (AI-344): Check that the accessibility level
-- of the type of the output object is not deeper than
-- that of the attribute's prefix type.
-- if Get_Access_Level (Item'Tag)
-- /= Get_Access_Level (P_Type'Tag)
-- then
-- raise Tag_Error;
-- end if;
-- String'Output (Strm, External_Tag (Item'Tag));
-- We cannot figure out a practical way to implement this
-- accessibility check on virtual machines, so we omit it.
if Ada_Version >= Ada_2005
and then Tagged_Type_Expansion
then
Insert_Action (N,
Make_Implicit_If_Statement (N,
Condition =>
Make_Op_Ne (Loc,
Left_Opnd =>
Build_Get_Access_Level (Loc,
Make_Attribute_Reference (Loc,
Prefix =>
Relocate_Node (
Duplicate_Subexpr (Item,
Name_Req => True)),
Attribute_Name => Name_Tag)),
Right_Opnd =>
Make_Integer_Literal (Loc,
Type_Access_Level (P_Type))),
Then_Statements =>
New_List (Make_Raise_Statement (Loc,
New_Occurrence_Of (
RTE (RE_Tag_Error), Loc)))));
end if;
Insert_Action (N,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Standard_String, Loc),
Attribute_Name => Name_Output,
Expressions => New_List (
Relocate_Node (Duplicate_Subexpr (Strm)),
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_External_Tag), Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
Relocate_Node
(Duplicate_Subexpr (Item, Name_Req => True)),
Attribute_Name => Name_Tag))))));
end Tag_Write;
Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
-- Tagged type case, use the primitive Output function
elsif Is_Tagged_Type (U_Type) then
Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
-- All other record type cases, including protected records.
-- The latter only arise for expander generated code for
-- handling shared passive partition access.
else
pragma Assert
(Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
-- Ada 2005 (AI-216): Program_Error is raised when executing
-- the default implementation of the Output attribute of an
-- unchecked union type if the type lacks default discriminant
-- values.
if Is_Unchecked_Union (Base_Type (U_Type))
and then
No (Discriminant_Default_Value (First_Discriminant (U_Type)))
then
Rewrite (N,
Make_Raise_Program_Error (Loc,
Reason => PE_Unchecked_Union_Restriction));
Set_Etype (N, Standard_Void_Type);
return;
end if;
Build_Record_Or_Elementary_Output_Procedure
(Loc, Base_Type (U_Type), Decl, Pname);
Insert_Action (N, Decl);
end if;
end if;
-- If we fall through, Pname is the name of the procedure to call
Rewrite_Attribute_Proc_Call (Pname);
end Output;
---------
-- Pos --
---------
-- For enumeration types, with a non-standard representation we generate
-- a call to the _Rep_To_Pos function created when the type was frozen.
-- The call has the form:
-- _rep_to_pos (expr, flag)
-- The parameter flag is True if range checks are enabled, causing
-- Program_Error to be raised if the expression has an invalid
-- representation, and False if range checks are suppressed.
-- For enumeration types with a standard representation, Pos can be
-- rewritten as a simple conversion with Conversion_OK set.
-- For integer types, Pos is equivalent to a simple integer conversion
-- and we rewrite it as such.
when Attribute_Pos => Pos : declare
Expr : constant Node_Id := First (Exprs);
Etyp : Entity_Id := Base_Type (Ptyp);
begin
-- Deal with zero/non-zero boolean values
if Is_Boolean_Type (Etyp) then
Adjust_Condition (Expr);
Etyp := Standard_Boolean;
Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc));
end if;
-- Case of enumeration type
if Is_Enumeration_Type (Etyp) then
-- Non-standard enumeration type (generate call)
if Present (Enum_Pos_To_Rep (Etyp)) then
Append_To (Exprs, Rep_To_Pos_Flag (Etyp, Loc));
Rewrite (N,
Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (TSS (Etyp, TSS_Rep_To_Pos), Loc),
Parameter_Associations => Exprs)));
-- Standard enumeration type (replace by conversion)
-- This is simply a direct conversion from the enumeration type to
-- the target integer type, which is treated by the back end as a
-- normal integer conversion, treating the enumeration type as an
-- integer, which is exactly what we want. We set Conversion_OK to
-- make sure that the analyzer does not complain about what might
-- be an illegal conversion.
-- However the target type is universal integer in most cases,
-- which is a very large type, so we first convert to a small
-- signed integer type in order not to lose the size information.
else
Rewrite (N, OK_Convert_To (Get_Integer_Type (Ptyp), Expr));
Convert_To_And_Rewrite (Typ, N);
end if;
-- Deal with integer types (replace by conversion)
else
Rewrite (N, Convert_To (Typ, Expr));
end if;
Analyze_And_Resolve (N, Typ);
end Pos;
--------------
-- Position --
--------------
-- We leave the computation up to the back end, since we don't know what
-- layout will be chosen if no component clause was specified.
when Attribute_Position =>
Apply_Universal_Integer_Attribute_Checks (N);
----------
-- Pred --
----------
-- 1. Deal with enumeration types with holes.
-- 2. For floating-point, generate call to attribute function.
-- 3. For other cases, deal with constraint checking.
when Attribute_Pred => Pred : declare
Etyp : constant Entity_Id := Base_Type (Ptyp);
begin
-- For enumeration types with non-standard representations, we
-- expand typ'Pred (x) into:
-- Pos_To_Rep (Rep_To_Pos (x) - 1)
-- if the representation is non-contiguous, and just x - 1 if it is
-- after having dealt with constraint checking.
if Is_Enumeration_Type (Etyp)
and then Present (Enum_Pos_To_Rep (Etyp))
then
if Has_Contiguous_Rep (Etyp) then
if not Range_Checks_Suppressed (Ptyp) then
Set_Do_Range_Check (First (Exprs), False);
Expand_Pred_Succ_Attribute (N);
end if;
Rewrite (N,
Unchecked_Convert_To (Etyp,
Make_Op_Subtract (Loc,
Left_Opnd =>
Unchecked_Convert_To (
Integer_Type_For
(Esize (Etyp), Is_Unsigned_Type (Etyp)),
First (Exprs)),
Right_Opnd =>
Make_Integer_Literal (Loc, 1))));
else
-- Add Boolean parameter True, to request program error if
-- we have a bad representation on our hands. If checks are
-- suppressed, then add False instead
Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
Rewrite (N,
Make_Indexed_Component (Loc,
Prefix =>
New_Occurrence_Of
(Enum_Pos_To_Rep (Etyp), Loc),
Expressions => New_List (
Make_Op_Subtract (Loc,
Left_Opnd =>
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of
(TSS (Etyp, TSS_Rep_To_Pos), Loc),
Parameter_Associations => Exprs),
Right_Opnd => Make_Integer_Literal (Loc, 1)))));
end if;
-- Suppress checks since they have all been done above
Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
-- For floating-point, we transform 'Pred into a call to the Pred
-- floating-point attribute function in Fat_xxx (xxx is root type).
-- Note that this function takes care of the overflow case.
elsif Is_Floating_Point_Type (Ptyp) then
Expand_Fpt_Attribute_R (N);
Analyze_And_Resolve (N, Typ);
-- For modular types, nothing to do (no overflow, since wraps)
elsif Is_Modular_Integer_Type (Ptyp) then
null;
-- For other types, if argument is marked as needing a range check or
-- overflow checking is enabled, we must generate a check.
elsif not Overflow_Checks_Suppressed (Ptyp)
or else Do_Range_Check (First (Exprs))
then
Set_Do_Range_Check (First (Exprs), False);
Expand_Pred_Succ_Attribute (N);
end if;
end Pred;
----------------------------------
-- Preelaborable_Initialization --
----------------------------------
when Attribute_Preelaborable_Initialization =>
-- This attribute should already be folded during analysis, but if
-- for some reason it hasn't been, we fold it now.
Fold_Uint
(N,
UI_From_Int
(Boolean'Pos (Has_Preelaborable_Initialization (Ptyp))),
Static => False);
--------------
-- Priority --
--------------
-- Ada 2005 (AI-327): Dynamic ceiling priorities
-- We rewrite X'Priority as the following run-time call:
-- Get_Ceiling (X._Object)
-- Note that although X'Priority is notionally an object, it is quite
-- deliberately not defined as an aliased object in the RM. This means
-- that it works fine to rewrite it as a call, without having to worry
-- about complications that would other arise from X'Priority'Access,
-- which is illegal, because of the lack of aliasing.
when Attribute_Priority => Priority : declare
Call : Node_Id;
Conctyp : Entity_Id;
New_Itype : Entity_Id;
Object_Parm : Node_Id;
Subprg : Entity_Id;
RT_Subprg_Name : Node_Id;
begin
-- Look for the enclosing concurrent type
Conctyp := Current_Scope;
while not Is_Concurrent_Type (Conctyp) loop
Conctyp := Scope (Conctyp);
end loop;
pragma Assert (Is_Protected_Type (Conctyp));
-- Generate the actual of the call
Subprg := Current_Scope;
while not Present (Protected_Body_Subprogram (Subprg)) loop
Subprg := Scope (Subprg);
end loop;
-- Use of 'Priority inside protected entries and barriers (in both
-- cases the type of the first formal of their expanded subprogram
-- is Address)
if Etype (First_Entity (Protected_Body_Subprogram (Subprg))) =
RTE (RE_Address)
then
-- In the expansion of protected entries the type of the first
-- formal of the Protected_Body_Subprogram is an Address. In order
-- to reference the _object component we generate:
-- type T is access p__ptTV;
-- freeze T []
New_Itype := Create_Itype (E_Access_Type, N);
Set_Etype (New_Itype, New_Itype);
Set_Directly_Designated_Type (New_Itype,
Corresponding_Record_Type (Conctyp));
Freeze_Itype (New_Itype, N);
-- Generate:
-- T!(O)._object'unchecked_access
Object_Parm :=
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix =>
Unchecked_Convert_To (New_Itype,
New_Occurrence_Of
(First_Entity (Protected_Body_Subprogram (Subprg)),
Loc)),
Selector_Name => Make_Identifier (Loc, Name_uObject)),
Attribute_Name => Name_Unchecked_Access);
-- Use of 'Priority inside a protected subprogram
else
Object_Parm :=
Make_Attribute_Reference (Loc,
Prefix =>
Make_Selected_Component (Loc,
Prefix =>
New_Occurrence_Of
(First_Entity (Protected_Body_Subprogram (Subprg)),
Loc),
Selector_Name => Make_Identifier (Loc, Name_uObject)),
Attribute_Name => Name_Unchecked_Access);
end if;
-- Select the appropriate run-time subprogram
if Number_Entries (Conctyp) = 0 then
RT_Subprg_Name := New_Occurrence_Of (RTE (RE_Get_Ceiling), Loc);
else
RT_Subprg_Name := New_Occurrence_Of (RTE (RO_PE_Get_Ceiling), Loc);
end if;
Call :=
Make_Function_Call (Loc,
Name => RT_Subprg_Name,
Parameter_Associations => New_List (Object_Parm));
Rewrite (N, Call);
-- Avoid the generation of extra checks on the pointer to the
-- protected object.
Analyze_And_Resolve (N, Typ, Suppress => Access_Check);
end Priority;
---------------
-- Put_Image --
---------------
when Attribute_Put_Image => Put_Image : declare
use Exp_Put_Image;
U_Type : constant Entity_Id := Underlying_Type (Entity (Pref));
Pname : Entity_Id;
Decl : Node_Id;
begin
-- If no underlying type, we have an error that will be diagnosed
-- elsewhere, so here we just completely ignore the expansion.
if No (U_Type) then
return;
end if;
-- If there is a TSS for Put_Image, just call it. This is true for
-- tagged types (if enabled) and if there is a user-specified
-- Put_Image.
Pname := TSS (U_Type, TSS_Put_Image);
if No (Pname) then
if Is_Tagged_Type (U_Type) and then Is_Derived_Type (U_Type) then
Pname := Find_Optional_Prim_Op (U_Type, TSS_Put_Image);
else
Pname := Find_Inherited_TSS (U_Type, TSS_Put_Image);
end if;
end if;
if No (Pname) then
-- If Put_Image is disabled, call the "unknown" version
if not Enable_Put_Image (U_Type) then
Rewrite (N, Build_Unknown_Put_Image_Call (N));
Analyze (N);
return;
-- For elementary types, we call the routine in System.Put_Images
-- directly.
elsif Is_Elementary_Type (U_Type) then
Rewrite (N, Build_Elementary_Put_Image_Call (N));
Analyze (N);
return;
elsif Is_Standard_String_Type (U_Type) then
Rewrite (N, Build_String_Put_Image_Call (N));
Analyze (N);
return;
elsif Is_Array_Type (U_Type) then
Build_Array_Put_Image_Procedure (N, U_Type, Decl, Pname);
Insert_Action (N, Decl);
-- Tagged type case, use the primitive Put_Image function. Note
-- that this will dispatch in the class-wide case which is what we
-- want.
elsif Is_Tagged_Type (U_Type) then
Pname := Find_Optional_Prim_Op (U_Type, TSS_Put_Image);
-- ????Need Find_Optional_Prim_Op instead of Find_Prim_Op,
-- because we might be deriving from a predefined type, which
-- currently has Enable_Put_Image False.
if No (Pname) then
Rewrite (N, Build_Unknown_Put_Image_Call (N));
Analyze (N);
return;
end if;
elsif Is_Protected_Type (U_Type) then
Rewrite (N, Build_Protected_Put_Image_Call (N));
Analyze (N);
return;
elsif Is_Task_Type (U_Type) then
Rewrite (N, Build_Task_Put_Image_Call (N));
Analyze (N);
return;
-- All other record type cases
else
pragma Assert (Is_Record_Type (U_Type));
Build_Record_Put_Image_Procedure
(Loc, Full_Base (U_Type), Decl, Pname);
Insert_Action (N, Decl);
end if;
end if;
-- If we fall through, Pname is the procedure to be called
Rewrite_Attribute_Proc_Call (Pname);
end Put_Image;
------------------
-- Range_Length --
------------------
when Attribute_Range_Length =>
-- The only special processing required is for the case where
-- Range_Length is applied to an enumeration type with holes.
-- In this case we transform
-- X'Range_Length
-- to
-- X'Pos (X'Last) - X'Pos (X'First) + 1
-- So that the result reflects the proper Pos values instead
-- of the underlying representations.
if Is_Enumeration_Type (Ptyp)
and then Has_Non_Standard_Rep (Ptyp)
then
Rewrite (N,
Make_Op_Add (Loc,
Left_Opnd =>
Make_Op_Subtract (Loc,
Left_Opnd =>
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Pos,
Prefix => New_Occurrence_Of (Ptyp, Loc),
Expressions => New_List (
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Last,
Prefix =>
New_Occurrence_Of (Ptyp, Loc)))),
Right_Opnd =>
Make_Attribute_Reference (Loc,
Attribute_Name => Name_Pos,
Prefix => New_Occurrence_Of (Ptyp, Loc),
Expressions => New_List (
Make_Attribute_Reference (Loc,
Attribute_Name => Name_First,
Prefix =>
New_Occurrence_Of (Ptyp, Loc))))),
Right_Opnd => Make_Integer_Literal (Loc, 1)));
Analyze_And_Resolve (N, Typ);
-- For all other cases, the attribute is handled by the back end, but
-- we need to deal with the case of the range check on a universal
-- integer.
else
Apply_Universal_Integer_Attribute_Checks (N);
end if;
------------
-- Reduce --
------------
when Attribute_Reduce =>
declare
Loc : constant Source_Ptr := Sloc (N);
E1 : constant Node_Id := First (Expressions (N));
E2 : constant Node_Id := Next (E1);
Bnn : constant Entity_Id := Make_Temporary (Loc, 'B', N);
Typ : constant Entity_Id := Etype (N);
New_Loop : Node_Id;
Stat : Node_Id;
function Build_Stat (Comp : Node_Id) return Node_Id;
-- The reducer can be a function, a procedure whose first
-- parameter is in-out, or an attribute that is a function,
-- which (for now) can only be Min/Max. This subprogram
-- builds the corresponding computation for the generated loop.
----------------
-- Build_Stat --
----------------
function Build_Stat (Comp : Node_Id) return Node_Id is
begin
if Nkind (E1) = N_Attribute_Reference then
Stat := Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (Bnn, Loc),
Expression => Make_Attribute_Reference (Loc,
Attribute_Name => Attribute_Name (E1),
Prefix => New_Copy (Prefix (E1)),
Expressions => New_List (
New_Occurrence_Of (Bnn, Loc),
Comp)));
elsif Ekind (Entity (E1)) = E_Procedure then
Stat := Make_Procedure_Call_Statement (Loc,
Name => New_Occurrence_Of (Entity (E1), Loc),
Parameter_Associations => New_List (
New_Occurrence_Of (Bnn, Loc),
Comp));
else
Stat := Make_Assignment_Statement (Loc,
Name => New_Occurrence_Of (Bnn, Loc),
Expression => Make_Function_Call (Loc,
Name => New_Occurrence_Of (Entity (E1), Loc),
Parameter_Associations => New_List (
New_Occurrence_Of (Bnn, Loc),
Comp)));
end if;
return Stat;
end Build_Stat;
-- If the prefix is an aggregate, its unique component is an
-- Iterated_Element, and we create a loop out of its iterator.
-- The iterated_component_association is parsed as a loop parameter
-- specification with "in" or as a container iterator with "of".
begin
if Nkind (Prefix (N)) = N_Aggregate then
declare
Stream : constant Node_Id :=
First (Component_Associations (Prefix (N)));
Expr : constant Node_Id := Expression (Stream);
Id : constant Node_Id := Defining_Identifier (Stream);
It_Spec : constant Node_Id :=
Iterator_Specification (Stream);
Ch : Node_Id;
Iter : Node_Id;
begin
-- Iteration may be given by an element iterator:
if Nkind (Stream) = N_Iterated_Component_Association
and then Present (It_Spec)
and then Of_Present (It_Spec)
then
Iter :=
Make_Iteration_Scheme (Loc,
Iterator_Specification =>
Relocate_Node (It_Spec),
Loop_Parameter_Specification => Empty);
else
Ch := First (Discrete_Choices (Stream));
Iter :=
Make_Iteration_Scheme (Loc,
Iterator_Specification => Empty,
Loop_Parameter_Specification =>
Make_Loop_Parameter_Specification (Loc,
Defining_Identifier => New_Copy (Id),
Discrete_Subtype_Definition =>
Relocate_Node (Ch)));
end if;
New_Loop := Make_Loop_Statement (Loc,
Iteration_Scheme => Iter,
End_Label => Empty,
Statements =>
New_List (Build_Stat (Relocate_Node (Expr))));
end;
else
-- If the prefix is a name, we construct an element iterator
-- over it. Its expansion will verify that it is an array or
-- a container with the proper aspects.
declare
Iter : Node_Id;
Elem : constant Entity_Id := Make_Temporary (Loc, 'E', N);
begin
Iter :=
Make_Iterator_Specification (Loc,
Defining_Identifier => Elem,
Name => Relocate_Node (Prefix (N)),
Subtype_Indication => Empty);
Set_Of_Present (Iter);
New_Loop := Make_Loop_Statement (Loc,
Iteration_Scheme =>
Make_Iteration_Scheme (Loc,
Iterator_Specification => Iter,
Loop_Parameter_Specification => Empty),
End_Label => Empty,
Statements => New_List (
Build_Stat (New_Occurrence_Of (Elem, Loc))));
end;
end if;
Rewrite (N,
Make_Expression_With_Actions (Loc,
Actions => New_List (
Make_Object_Declaration (Loc,
Defining_Identifier => Bnn,
Object_Definition =>
New_Occurrence_Of (Typ, Loc),
Expression => Relocate_Node (E2)), New_Loop),
Expression => New_Occurrence_Of (Bnn, Loc)));
Analyze_And_Resolve (N, Typ);
end;
----------
-- Read --
----------
when Attribute_Read => Read : declare
P_Type : constant Entity_Id := Entity (Pref);
B_Type : constant Entity_Id := Base_Type (P_Type);
U_Type : constant Entity_Id := Underlying_Type (P_Type);
Pname : Entity_Id;
Decl : Node_Id;
Prag : Node_Id;
Arg2 : Node_Id;
Rfunc : Node_Id;
Lhs : Node_Id;
Rhs : Node_Id;
begin
-- If no underlying type, we have an error that will be diagnosed
-- elsewhere, so here we just completely ignore the expansion.
if No (U_Type) then
return;
end if;
-- Stream operations can appear in user code even if the restriction
-- No_Streams is active (for example, when instantiating a predefined
-- container). In that case rewrite the attribute as a Raise to
-- prevent any run-time use.
if Restriction_Active (No_Streams) then
Rewrite (N,
Make_Raise_Program_Error (Sloc (N),
Reason => PE_Stream_Operation_Not_Allowed));
Set_Etype (N, B_Type);
return;
end if;
-- The simple case, if there is a TSS for Read, just call it
Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Read);
if Present (Pname) then
null;
else
-- If there is a Stream_Convert pragma, use it, we rewrite
-- sourcetyp'Read (stream, Item)
-- as
-- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
-- where strmread is the given Read function that converts an
-- argument of type strmtyp to type sourcetyp or a type from which
-- it is derived. The conversion to sourcetyp is required in the
-- latter case.
-- A special case arises if Item is a type conversion in which
-- case, we have to expand to:
-- Itemx := typex (strmread (strmtyp'Input (Stream)));
-- where Itemx is the expression of the type conversion (i.e.
-- the actual object), and typex is the type of Itemx.
Prag := Get_Stream_Convert_Pragma (P_Type);
if Present (Prag) then
Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
Rfunc := Entity (Expression (Arg2));
Lhs := Relocate_Node (Next (First (Exprs)));
Rhs :=
OK_Convert_To (B_Type,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Rfunc, Loc),
Parameter_Associations => New_List (
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of
(Etype (First_Formal (Rfunc)), Loc),
Attribute_Name => Name_Input,
Expressions => New_List (
Relocate_Node (First (Exprs)))))));
if Nkind (Lhs) = N_Type_Conversion then
Lhs := Expression (Lhs);
Rhs := Convert_To (Etype (Lhs), Rhs);
end if;
Rewrite (N,
Make_Assignment_Statement (Loc,
Name => Lhs,
Expression => Rhs));
Set_Assignment_OK (Lhs);
Analyze (N);
return;
-- Limited types
elsif Default_Streaming_Unavailable (U_Type) then
-- Do the same thing here as is done above in the
-- case where a No_Streams restriction is active.
Rewrite (N,
Make_Raise_Program_Error (Sloc (N),
Reason => PE_Stream_Operation_Not_Allowed));
Set_Etype (N, B_Type);
return;
-- For elementary types, we call the I_xxx routine using the first
-- parameter and then assign the result into the second parameter.
-- We set Assignment_OK to deal with the conversion case.
elsif Is_Elementary_Type (U_Type) then
declare
Lhs : Node_Id;
Rhs : Node_Id;
begin
Lhs := Relocate_Node (Next (First (Exprs)));
Rhs := Build_Elementary_Input_Call (N);
if Nkind (Lhs) = N_Type_Conversion then
Lhs := Expression (Lhs);
Rhs := Convert_To (Etype (Lhs), Rhs);
end if;
Set_Assignment_OK (Lhs);
Rewrite (N,
Make_Assignment_Statement (Loc,
Name => Lhs,
Expression => Rhs));
Analyze (N);
return;
end;
-- Array type case
elsif Is_Array_Type (U_Type) then
Build_Array_Read_Procedure (N, U_Type, Decl, Pname);
Compile_Stream_Body_In_Scope (N, Decl, U_Type);
-- Tagged type case, use the primitive Read function. Note that
-- this will dispatch in the class-wide case which is what we want
elsif Is_Tagged_Type (U_Type) then
Pname := Find_Prim_Op (U_Type, TSS_Stream_Read);
-- All other record type cases, including protected records. The
-- latter only arise for expander generated code for handling
-- shared passive partition access.
else
pragma Assert
(Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
-- Ada 2005 (AI-216): Program_Error is raised when executing
-- the default implementation of the Read attribute of an
-- Unchecked_Union type. We replace the attribute with a
-- raise statement (rather than inserting it before) to handle
-- properly the case of an unchecked union that is a record
-- component.
if Is_Unchecked_Union (Base_Type (U_Type)) then
Rewrite (N,
Make_Raise_Program_Error (Loc,
Reason => PE_Unchecked_Union_Restriction));
Set_Etype (N, B_Type);
return;
end if;
if Has_Defaulted_Discriminants (U_Type) then
Build_Mutable_Record_Read_Procedure
(Loc, Full_Base (U_Type), Decl, Pname);
else
Build_Record_Read_Procedure
(Loc, Full_Base (U_Type), Decl, Pname);
end if;
Insert_Action (N, Decl);
end if;
end if;
Rewrite_Attribute_Proc_Call (Pname);
end Read;
---------
-- Ref --
---------
-- Ref is identical to To_Address, see To_Address for processing
---------------
-- Remainder --
---------------
-- Transforms 'Remainder into a call to the floating-point attribute
-- function Remainder in Fat_xxx (where xxx is the root type)
when Attribute_Remainder =>
Expand_Fpt_Attribute_RR (N);
------------
-- Result --
------------
-- Transform 'Result into reference to _Result formal. At the point
-- where a legal 'Result attribute is expanded, we know that we are in
-- the context of a _Postcondition function with a _Result parameter.
when Attribute_Result =>
Rewrite (N, Make_Identifier (Loc, Chars => Name_uResult));
Analyze_And_Resolve (N, Typ);
-----------
-- Round --
-----------
-- The handling of the Round attribute is delicate when the operand is
-- universal fixed. In this case, the processing in Sem_Attr introduced
-- a conversion to universal real, reflecting the semantics of Round,
-- but we do not want anything to do with universal real at run time,
-- since this corresponds to using floating-point arithmetic.
-- What we have now is that the Etype of the Round attribute correctly
-- indicates the final result type. The operand of the Round is the
-- conversion to universal real, described above, and the operand of
-- this conversion is the actual operand of Round, which may be the
-- special case of a fixed point multiplication or division.
-- The expander will expand first the operand of the conversion, then
-- the conversion, and finally the round attribute itself, since we
-- always work inside out. But we cannot simply process naively in this
-- order. In the semantic world where universal fixed and real really
-- exist and have infinite precision, there is no problem, but in the
-- implementation world, where universal real is a floating-point type,
-- we would get the wrong result.
-- So the approach is as follows. When expanding a multiply or divide
-- whose type is universal fixed, Fixup_Universal_Fixed_Operation will
-- look up and skip the conversion to universal real if its parent is
-- a Round attribute, taking information from this attribute node. In
-- the other cases, Expand_N_Type_Conversion does the same by looking
-- at its parent to see if it is a Round attribute, before calling the
-- fixed-point expansion routine.
-- This means that by the time we get to expanding the Round attribute
-- itself, the Round is nothing more than a type conversion (and will
-- often be a null type conversion), so we just replace it with the
-- appropriate conversion operation.
when Attribute_Round =>
if Etype (First (Exprs)) = Etype (N) then
Rewrite (N, Relocate_Node (First (Exprs)));
else
Rewrite (N, Convert_To (Etype (N), First (Exprs)));
Set_Rounded_Result (N);
end if;
Analyze_And_Resolve (N);
--------------
-- Rounding --
--------------
-- Transforms 'Rounding into a call to the floating-point attribute
-- function Rounding in Fat_xxx (where xxx is the root type)
-- Expansion is avoided for cases the back end can handle directly.
when Attribute_Rounding =>
if not Is_Inline_Floating_Point_Attribute (N) then
Expand_Fpt_Attribute_R (N);
end if;
-------------
-- Scaling --
-------------
-- Transforms 'Scaling into a call to the floating-point attribute
-- function Scaling in Fat_xxx (where xxx is the root type)
when Attribute_Scaling =>
Expand_Fpt_Attribute_RI (N);
----------------------------------------
-- Simple_Storage_Pool & Storage_Pool --
----------------------------------------
when Attribute_Simple_Storage_Pool | Attribute_Storage_Pool =>
Rewrite (N,
Make_Type_Conversion (Loc,
Subtype_Mark => New_Occurrence_Of (Etype (N), Loc),
Expression => New_Occurrence_Of (Entity (N), Loc)));
Analyze_And_Resolve (N, Typ);
----------
-- Size --
----------
when Attribute_Object_Size
| Attribute_Size
| Attribute_Value_Size
| Attribute_VADS_Size
=>
Size : declare
New_Node : Node_Id;
begin
-- Processing for VADS_Size case. Note that this processing
-- removes all traces of VADS_Size from the tree, and completes
-- all required processing for VADS_Size by translating the
-- attribute reference to an appropriate Size or Object_Size
-- reference.
if Id = Attribute_VADS_Size
or else (Use_VADS_Size and then Id = Attribute_Size)
then
-- If the size is specified, then we simply use the specified
-- size. This applies to both types and objects. The size of an
-- object can be specified in the following ways:
-- An explicit size clause is given for an object
-- A component size is specified for an indexed component
-- A component clause is specified for a selected component
-- The object is a component of a packed composite object
-- If the size is specified, then VADS_Size of an object
if (Is_Entity_Name (Pref)
and then Present (Size_Clause (Entity (Pref))))
or else
(Nkind (Pref) = N_Component_Clause
and then (Present (Component_Clause
(Entity (Selector_Name (Pref))))
or else Is_Packed (Etype (Prefix (Pref)))))
or else
(Nkind (Pref) = N_Indexed_Component
and then (Known_Component_Size (Etype (Prefix (Pref)))
or else Is_Packed (Etype (Prefix (Pref)))))
then
Set_Attribute_Name (N, Name_Size);
-- Otherwise if we have an object rather than a type, then
-- the VADS_Size attribute applies to the type of the object,
-- rather than the object itself. This is one of the respects
-- in which VADS_Size differs from Size.
else
if (not Is_Entity_Name (Pref)
or else not Is_Type (Entity (Pref)))
and then (Is_Scalar_Type (Ptyp)
or else Is_Constrained (Ptyp))
then
Rewrite (Pref, New_Occurrence_Of (Ptyp, Loc));
end if;
-- For a scalar type for which no size was explicitly given,
-- VADS_Size means Object_Size. This is the other respect in
-- which VADS_Size differs from Size.
if Is_Scalar_Type (Ptyp)
and then No (Size_Clause (Ptyp))
then
Set_Attribute_Name (N, Name_Object_Size);
-- In all other cases, Size and VADS_Size are the same
else
Set_Attribute_Name (N, Name_Size);
end if;
end if;
end if;
-- If the prefix is X'Class, transform it into a direct reference
-- to the class-wide type, because the back end must not see a
-- 'Class reference.
if Is_Entity_Name (Pref)
and then Is_Class_Wide_Type (Entity (Pref))
then
Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
return;
-- For X'Size applied to an object of a class-wide type, transform
-- X'Size into a call to the primitive operation _Size applied to
-- X.
elsif Is_Class_Wide_Type (Ptyp) then
-- No need to do anything else compiling under restriction
-- No_Dispatching_Calls. During the semantic analysis we
-- already noted this restriction violation.
if Restriction_Active (No_Dispatching_Calls) then
return;
end if;
New_Node :=
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (Find_Prim_Op (Ptyp, Name_uSize), Loc),
Parameter_Associations => New_List (Pref));
if Typ /= Standard_Long_Long_Integer then
-- The context is a specific integer type with which the
-- original attribute was compatible. The function has a
-- specific type as well, so to preserve the compatibility
-- we must convert explicitly.
New_Node := Convert_To (Typ, New_Node);
end if;
Rewrite (N, New_Node);
Analyze_And_Resolve (N, Typ);
return;
end if;
-- Call Expand_Size_Attribute to do the final part of the
-- expansion which is shared with GNATprove expansion.
Expand_Size_Attribute (N);
end Size;
------------------
-- Storage_Size --
------------------
when Attribute_Storage_Size => Storage_Size : declare
Alloc_Op : Entity_Id := Empty;
begin
-- Access type case, always go to the root type
-- The case of access types results in a value of zero for the case
-- where no storage size attribute clause has been given. If a
-- storage size has been given, then the attribute is converted
-- to a reference to the variable used to hold this value.
if Is_Access_Type (Ptyp) then
if Present (Storage_Size_Variable (Root_Type (Ptyp))) then
Rewrite (N,
Convert_To (Typ,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of
(Etype (Storage_Size_Variable (Root_Type (Ptyp))), Loc),
Attribute_Name => Name_Max,
Expressions => New_List (
Make_Integer_Literal (Loc, 0),
New_Occurrence_Of
(Storage_Size_Variable (Root_Type (Ptyp)), Loc)))));
elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then
-- If the access type is associated with a simple storage pool
-- object, then attempt to locate the optional Storage_Size
-- function of the simple storage pool type. If not found,
-- then the result will default to zero.
if Present (Get_Rep_Pragma (Root_Type (Ptyp),
Name_Simple_Storage_Pool_Type))
then
declare
Pool_Type : constant Entity_Id :=
Base_Type (Etype (Entity (N)));
begin
Alloc_Op := Get_Name_Entity_Id (Name_Storage_Size);
while Present (Alloc_Op) loop
if Scope (Alloc_Op) = Scope (Pool_Type)
and then Present (First_Formal (Alloc_Op))
and then Etype (First_Formal (Alloc_Op)) = Pool_Type
then
exit;
end if;
Alloc_Op := Homonym (Alloc_Op);
end loop;
end;
-- In the normal Storage_Pool case, retrieve the primitive
-- function associated with the pool type.
else
Alloc_Op :=
Find_Prim_Op
(Etype (Associated_Storage_Pool (Root_Type (Ptyp))),
Attribute_Name (N));
end if;
-- If Storage_Size wasn't found (can only occur in the simple
-- storage pool case), then simply use zero for the result.
if not Present (Alloc_Op) then
Rewrite (N, Make_Integer_Literal (Loc, 0));
-- Otherwise, rewrite the allocator as a call to pool type's
-- Storage_Size function.
else
Rewrite (N,
Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (Alloc_Op, Loc),
Parameter_Associations => New_List (
New_Occurrence_Of
(Associated_Storage_Pool
(Root_Type (Ptyp)), Loc)))));
end if;
else
Rewrite (N, Make_Integer_Literal (Loc, 0));
end if;
Analyze_And_Resolve (N, Typ);
-- For tasks, we retrieve the size directly from the TCB. The
-- size may depend on a discriminant of the type, and therefore
-- can be a per-object expression, so type-level information is
-- not sufficient in general. There are four cases to consider:
-- a) If the attribute appears within a task body, the designated
-- TCB is obtained by a call to Self.
-- b) If the prefix of the attribute is the name of a task object,
-- the designated TCB is the one stored in the corresponding record.
-- c) If the prefix is a task type, the size is obtained from the
-- size variable created for each task type
-- d) If no Storage_Size was specified for the type, there is no
-- size variable, and the value is a system-specific default.
else
if In_Open_Scopes (Ptyp) then
-- Storage_Size (Self)
Rewrite (N,
Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
Parameter_Associations =>
New_List (
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Self), Loc))))));
elsif not Is_Entity_Name (Pref)
or else not Is_Type (Entity (Pref))
then
-- Storage_Size (Rec (Obj).Size)
Rewrite (N,
Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
Parameter_Associations =>
New_List (
Make_Selected_Component (Loc,
Prefix =>
Unchecked_Convert_To (
Corresponding_Record_Type (Ptyp),
New_Copy_Tree (Pref)),
Selector_Name =>
Make_Identifier (Loc, Name_uTask_Id))))));
elsif Present (Storage_Size_Variable (Ptyp)) then
-- Static Storage_Size pragma given for type: retrieve value
-- from its allocated storage variable.
Rewrite (N,
Convert_To (Typ,
Make_Function_Call (Loc,
Name => New_Occurrence_Of (
RTE (RE_Adjust_Storage_Size), Loc),
Parameter_Associations =>
New_List (
New_Occurrence_Of (
Storage_Size_Variable (Ptyp), Loc)))));
else
-- Get system default
Rewrite (N,
Convert_To (Typ,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (
RTE (RE_Default_Stack_Size), Loc))));
end if;
Analyze_And_Resolve (N, Typ);
end if;
end Storage_Size;
-----------------
-- Stream_Size --
-----------------
when Attribute_Stream_Size =>
Rewrite (N,
Make_Integer_Literal (Loc, Intval => Get_Stream_Size (Ptyp)));
Analyze_And_Resolve (N, Typ);
----------
-- Succ --
----------
-- 1. Deal with enumeration types with holes.
-- 2. For floating-point, generate call to attribute function.
-- 3. For other cases, deal with constraint checking.
when Attribute_Succ => Succ : declare
Etyp : constant Entity_Id := Base_Type (Ptyp);
begin
-- For enumeration types with non-standard representations, we
-- expand typ'Pred (x) into:
-- Pos_To_Rep (Rep_To_Pos (x) + 1)
-- if the representation is non-contiguous, and just x + 1 if it is
-- after having dealt with constraint checking.
if Is_Enumeration_Type (Etyp)
and then Present (Enum_Pos_To_Rep (Etyp))
then
if Has_Contiguous_Rep (Etyp) then
if not Range_Checks_Suppressed (Ptyp) then
Set_Do_Range_Check (First (Exprs), False);
Expand_Pred_Succ_Attribute (N);
end if;
Rewrite (N,
Unchecked_Convert_To (Etyp,
Make_Op_Add (Loc,
Left_Opnd =>
Unchecked_Convert_To (
Integer_Type_For
(Esize (Etyp), Is_Unsigned_Type (Etyp)),
First (Exprs)),
Right_Opnd =>
Make_Integer_Literal (Loc, 1))));
else
-- Add Boolean parameter True, to request program error if
-- we have a bad representation on our hands. Add False if
-- checks are suppressed.
Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
Rewrite (N,
Make_Indexed_Component (Loc,
Prefix =>
New_Occurrence_Of
(Enum_Pos_To_Rep (Etyp), Loc),
Expressions => New_List (
Make_Op_Add (Loc,
Left_Opnd =>
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of
(TSS (Etyp, TSS_Rep_To_Pos), Loc),
Parameter_Associations => Exprs),
Right_Opnd => Make_Integer_Literal (Loc, 1)))));
end if;
-- Suppress checks since they have all been done above
Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
-- For floating-point, we transform 'Succ into a call to the Succ
-- floating-point attribute function in Fat_xxx (xxx is root type)
elsif Is_Floating_Point_Type (Ptyp) then
Expand_Fpt_Attribute_R (N);
Analyze_And_Resolve (N, Typ);
-- For modular types, nothing to do (no overflow, since wraps)
elsif Is_Modular_Integer_Type (Ptyp) then
null;
-- For other types, if argument is marked as needing a range check or
-- overflow checking is enabled, we must generate a check.
elsif not Overflow_Checks_Suppressed (Ptyp)
or else Do_Range_Check (First (Exprs))
then
Set_Do_Range_Check (First (Exprs), False);
Expand_Pred_Succ_Attribute (N);
end if;
end Succ;
---------
-- Tag --
---------
-- Transforms X'Tag into a direct reference to the tag of X
when Attribute_Tag => Tag : declare
Ttyp : Entity_Id;
Prefix_Is_Type : Boolean;
begin
if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then
Ttyp := Entity (Pref);
Prefix_Is_Type := True;
else
Ttyp := Ptyp;
Prefix_Is_Type := False;
end if;
if Is_Class_Wide_Type (Ttyp) then
Ttyp := Root_Type (Ttyp);
end if;
Ttyp := Underlying_Type (Ttyp);
-- Ada 2005: The type may be a synchronized tagged type, in which
-- case the tag information is stored in the corresponding record.
if Is_Concurrent_Type (Ttyp) then
Ttyp := Corresponding_Record_Type (Ttyp);
end if;
if Prefix_Is_Type then
-- For VMs we leave the type attribute unexpanded because
-- there's not a dispatching table to reference.
if Tagged_Type_Expansion then
Rewrite (N,
Unchecked_Convert_To (RTE (RE_Tag),
New_Occurrence_Of
(Node (First_Elmt (Access_Disp_Table (Ttyp))), Loc)));
Analyze_And_Resolve (N, RTE (RE_Tag));
end if;
-- Ada 2005 (AI-251): The use of 'Tag in the sources always
-- references the primary tag of the actual object. If 'Tag is
-- applied to class-wide interface objects we generate code that
-- displaces "this" to reference the base of the object.
elsif Comes_From_Source (N)
and then Is_Class_Wide_Type (Etype (Prefix (N)))
and then Is_Interface (Underlying_Type (Etype (Prefix (N))))
then
-- Generate:
-- (To_Tag_Ptr (Prefix'Address)).all
-- Note that Prefix'Address is recursively expanded into a call
-- to Base_Address (Obj.Tag)
-- Not needed for VM targets, since all handled by the VM
if Tagged_Type_Expansion then
Rewrite (N,
Make_Explicit_Dereference (Loc,
Unchecked_Convert_To (RTE (RE_Tag_Ptr),
Make_Attribute_Reference (Loc,
Prefix => Relocate_Node (Pref),
Attribute_Name => Name_Address))));
Analyze_And_Resolve (N, RTE (RE_Tag));
end if;
else
Rewrite (N,
Make_Selected_Component (Loc,
Prefix => Relocate_Node (Pref),
Selector_Name =>
New_Occurrence_Of (First_Tag_Component (Ttyp), Loc)));
Analyze_And_Resolve (N, RTE (RE_Tag));
end if;
end Tag;
----------------
-- Terminated --
----------------
-- Transforms 'Terminated attribute into a call to Terminated function
when Attribute_Terminated => Terminated : begin
-- The prefix of Terminated is of a task interface class-wide type.
-- Generate:
-- terminated (Task_Id (_disp_get_task_id (Pref)));
if Ada_Version >= Ada_2005
and then Ekind (Ptyp) = E_Class_Wide_Type
and then Is_Interface (Ptyp)
and then Is_Task_Interface (Ptyp)
then
Rewrite (N,
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Terminated), Loc),
Parameter_Associations => New_List (
Unchecked_Convert_To
(RTE (RO_ST_Task_Id),
Build_Disp_Get_Task_Id_Call (Pref)))));
elsif Restricted_Profile then
Rewrite (N,
Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated)));
else
Rewrite (N,
Build_Call_With_Task (Pref, RTE (RE_Terminated)));
end if;
Analyze_And_Resolve (N, Standard_Boolean);
end Terminated;
----------------
-- To_Address --
----------------
-- Transforms System'To_Address (X) and System.Address'Ref (X) into
-- unchecked conversion from (integral) type of X to type address. If
-- the To_Address is a static expression, the transformed expression
-- also needs to be static, because we do some legality checks (e.g.
-- for Thread_Local_Storage) after this transformation.
when Attribute_Ref
| Attribute_To_Address
=>
To_Address : declare
Is_Static : constant Boolean := Is_Static_Expression (N);
begin
Rewrite (N,
Unchecked_Convert_To (RTE (RE_Address),
Relocate_Node (First (Exprs))));
Set_Is_Static_Expression (N, Is_Static);
Analyze_And_Resolve (N, RTE (RE_Address));
end To_Address;
------------
-- To_Any --
------------
when Attribute_To_Any => To_Any : declare
Decls : constant List_Id := New_List;
begin
Rewrite (N,
Build_To_Any_Call
(Loc,
Convert_To (Ptyp,
Relocate_Node (First (Exprs))), Decls));
Insert_Actions (N, Decls);
Analyze_And_Resolve (N, RTE (RE_Any));
end To_Any;
----------------
-- Truncation --
----------------
-- Transforms 'Truncation into a call to the floating-point attribute
-- function Truncation in Fat_xxx (where xxx is the root type).
-- Expansion is avoided for cases the back end can handle directly.
when Attribute_Truncation =>
if not Is_Inline_Floating_Point_Attribute (N) then
Expand_Fpt_Attribute_R (N);
end if;
--------------
-- TypeCode --
--------------
when Attribute_TypeCode => TypeCode : declare
Decls : constant List_Id := New_List;
begin
Rewrite (N, Build_TypeCode_Call (Loc, Ptyp, Decls));
Insert_Actions (N, Decls);
Analyze_And_Resolve (N, RTE (RE_TypeCode));
end TypeCode;
-----------------------
-- Unbiased_Rounding --
-----------------------
-- Transforms 'Unbiased_Rounding into a call to the floating-point
-- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
-- root type). Expansion is avoided for cases the back end can handle
-- directly.
when Attribute_Unbiased_Rounding =>
if not Is_Inline_Floating_Point_Attribute (N) then
Expand_Fpt_Attribute_R (N);
end if;
------------
-- Update --
------------
when Attribute_Update =>
Expand_Update_Attribute (N);
---------------
-- VADS_Size --
---------------
-- The processing for VADS_Size is shared with Size
---------
-- Val --
---------
-- For enumeration types with a non-standard representation we use the
-- _Pos_To_Rep array that was created when the type was frozen, unless
-- the representation is contiguous in which case we use an addition.
-- For enumeration types with a standard representation, Val can be
-- rewritten as a simple conversion with Conversion_OK set.
-- For integer types, Val is equivalent to a simple integer conversion
-- and we rewrite it as such.
when Attribute_Val => Val : declare
Etyp : constant Entity_Id := Base_Type (Ptyp);
Expr : constant Node_Id := First (Exprs);
Rtyp : Entity_Id;
begin
-- Case of enumeration type
if Is_Enumeration_Type (Etyp) then
-- Non-contiguous non-standard enumeration type
if Present (Enum_Pos_To_Rep (Etyp))
and then not Has_Contiguous_Rep (Etyp)
then
Rewrite (N,
Make_Indexed_Component (Loc,
Prefix =>
New_Occurrence_Of (Enum_Pos_To_Rep (Etyp), Loc),
Expressions => New_List (
Convert_To (Standard_Integer, Expr))));
Analyze_And_Resolve (N, Typ);
-- Standard or contiguous non-standard enumeration type
else
-- If the argument is marked as requiring a range check then
-- generate it here, after looking through a conversion to
-- universal integer, if any.
if Do_Range_Check (Expr) then
if Present (Enum_Pos_To_Rep (Etyp)) then
Rtyp := Enum_Pos_To_Rep (Etyp);
else
Rtyp := Etyp;
end if;
if Nkind (Expr) = N_Type_Conversion
and then Entity (Subtype_Mark (Expr)) = Universal_Integer
then
Generate_Range_Check
(Expression (Expr), Rtyp, CE_Range_Check_Failed);
else
Generate_Range_Check (Expr, Rtyp, CE_Range_Check_Failed);
end if;
Set_Do_Range_Check (Expr, False);
end if;
-- Contiguous non-standard enumeration type
if Present (Enum_Pos_To_Rep (Etyp)) then
Rewrite (N,
Unchecked_Convert_To (Etyp,
Make_Op_Add (Loc,
Left_Opnd =>
Make_Integer_Literal (Loc,
Enumeration_Rep (First_Literal (Etyp))),
Right_Opnd =>
Unchecked_Convert_To (
Integer_Type_For
(Esize (Etyp), Is_Unsigned_Type (Etyp)),
Expr))));
-- Standard enumeration type
else
Rewrite (N, OK_Convert_To (Typ, Expr));
end if;
-- Suppress checks since the range check was done above
-- and it guarantees that the addition cannot overflow.
Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
end if;
-- Deal with integer types
elsif Is_Integer_Type (Etyp) then
Rewrite (N, Convert_To (Typ, Expr));
Analyze_And_Resolve (N, Typ);
end if;
end Val;
-----------
-- Valid --
-----------
-- The code for valid is dependent on the particular types involved.
-- See separate sections below for the generated code in each case.
when Attribute_Valid => Valid : declare
PBtyp : Entity_Id := Base_Type (Ptyp);
Save_Validity_Checks_On : constant Boolean := Validity_Checks_On;
-- Save the validity checking mode. We always turn off validity
-- checking during process of 'Valid since this is one place
-- where we do not want the implicit validity checks to interfere
-- with the explicit validity check that the programmer is doing.
function Make_Range_Test return Node_Id;
-- Build the code for a range test of the form
-- PBtyp!(Pref) in PBtyp!(Ptyp'First) .. PBtyp!(Ptyp'Last)
---------------------
-- Make_Range_Test --
---------------------
function Make_Range_Test return Node_Id is
Temp : Node_Id;
begin
-- The prefix of attribute 'Valid should always denote an object
-- reference. The reference is either coming directly from source
-- or is produced by validity check expansion. The object may be
-- wrapped in a conversion in which case the call to Unqual_Conv
-- will yield it.
-- If the prefix denotes a variable which captures the value of
-- an object for validation purposes, use the variable in the
-- range test. This ensures that no extra copies or extra reads
-- are produced as part of the test. Generate:
-- Temp : ... := Object;
-- if not Temp in ... then
if Is_Validation_Variable_Reference (Pref) then
Temp := New_Occurrence_Of (Entity (Unqual_Conv (Pref)), Loc);
-- Otherwise the prefix is either a source object or a constant
-- produced by validity check expansion. Generate:
-- Temp : constant ... := Pref;
-- if not Temp in ... then
else
Temp := Duplicate_Subexpr (Pref);
end if;
return
Make_In (Loc,
Left_Opnd => Unchecked_Convert_To (PBtyp, Temp),
Right_Opnd =>
Make_Range (Loc,
Low_Bound =>
Unchecked_Convert_To (PBtyp,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ptyp, Loc),
Attribute_Name => Name_First)),
High_Bound =>
Unchecked_Convert_To (PBtyp,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ptyp, Loc),
Attribute_Name => Name_Last))));
end Make_Range_Test;
-- Local variables
Tst : Node_Id;
-- Start of processing for Attribute_Valid
begin
-- Do not expand sourced code 'Valid reference in CodePeer mode,
-- will be handled by the back-end directly.
if CodePeer_Mode and then Comes_From_Source (N) then
return;
end if;
-- Turn off validity checks. We do not want any implicit validity
-- checks to intefere with the explicit check from the attribute
Validity_Checks_On := False;
-- Retrieve the base type. Handle the case where the base type is a
-- private enumeration type.
if Is_Private_Type (PBtyp) and then Present (Full_View (PBtyp)) then
PBtyp := Full_View (PBtyp);
end if;
-- Floating-point case. This case is handled by the Valid attribute
-- code in the floating-point attribute run-time library.
if Is_Floating_Point_Type (Ptyp) then
Float_Valid : declare
Pkg : RE_Id;
Ftp : Entity_Id;
function Get_Fat_Entity (Nam : Name_Id) return Entity_Id;
-- Return entity for Pkg.Nam
--------------------
-- Get_Fat_Entity --
--------------------
function Get_Fat_Entity (Nam : Name_Id) return Entity_Id is
Exp_Name : constant Node_Id :=
Make_Selected_Component (Loc,
Prefix => New_Occurrence_Of (RTE (Pkg), Loc),
Selector_Name => Make_Identifier (Loc, Nam));
begin
Find_Selected_Component (Exp_Name);
return Entity (Exp_Name);
end Get_Fat_Entity;
-- Start of processing for Float_Valid
begin
-- The C back end handles Valid for floating-point types
if Modify_Tree_For_C then
Analyze_And_Resolve (Pref, Ptyp);
Set_Etype (N, Standard_Boolean);
Set_Analyzed (N);
else
Find_Fat_Info (Ptyp, Ftp, Pkg);
-- If the prefix is a reverse SSO component, or is possibly
-- unaligned, first create a temporary copy that is in
-- native SSO, and properly aligned. Make it Volatile to
-- prevent folding in the back-end. Note that we use an
-- intermediate constrained string type to initialize the
-- temporary, as the value at hand might be invalid, and in
-- that case it cannot be copied using a floating point
-- register.
if In_Reverse_Storage_Order_Object (Pref)
or else Is_Possibly_Unaligned_Object (Pref)
then
declare
Temp : constant Entity_Id :=
Make_Temporary (Loc, 'F');
Fat_S : constant Entity_Id :=
Get_Fat_Entity (Name_S);
-- Constrained string subtype of appropriate size
Fat_P : constant Entity_Id :=
Get_Fat_Entity (Name_P);
-- Access to Fat_S
Decl : constant Node_Id :=
Make_Object_Declaration (Loc,
Defining_Identifier => Temp,
Aliased_Present => True,
Object_Definition =>
New_Occurrence_Of (Ptyp, Loc));
begin
Set_Aspect_Specifications (Decl, New_List (
Make_Aspect_Specification (Loc,
Identifier =>
Make_Identifier (Loc, Name_Volatile))));
Insert_Actions (N,
New_List (
Decl,
Make_Assignment_Statement (Loc,
Name =>
Make_Explicit_Dereference (Loc,
Prefix =>
Unchecked_Convert_To (Fat_P,
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Temp, Loc),
Attribute_Name =>
Name_Unrestricted_Access))),
Expression =>
Unchecked_Convert_To (Fat_S,
Relocate_Node (Pref)))),
Suppress => All_Checks);
Rewrite (Pref, New_Occurrence_Of (Temp, Loc));
end;
end if;
-- We now have an object of the proper endianness and
-- alignment, and can construct a Valid attribute.
-- We make sure the prefix of this valid attribute is
-- marked as not coming from source, to avoid losing
-- warnings from 'Valid looking like a possible update.
Set_Comes_From_Source (Pref, False);
Expand_Fpt_Attribute
(N, Pkg, Name_Valid,
New_List (
Make_Attribute_Reference (Loc,
Prefix => Unchecked_Convert_To (Ftp, Pref),
Attribute_Name => Name_Unrestricted_Access)));
end if;
-- One more task, we still need a range check. Required
-- only if we have a constraint, since the Valid routine
-- catches infinities properly (infinities are never valid).
-- The way we do the range check is simply to create the
-- expression: Valid (N) and then Base_Type(Pref) in Typ.
if not Subtypes_Statically_Match (Ptyp, PBtyp) then
Rewrite (N,
Make_And_Then (Loc,
Left_Opnd => Relocate_Node (N),
Right_Opnd =>
Make_In (Loc,
Left_Opnd => Convert_To (PBtyp, Pref),
Right_Opnd => New_Occurrence_Of (Ptyp, Loc))));
end if;
end Float_Valid;
-- Enumeration type with holes
-- For enumeration types with holes, the Pos value constructed by
-- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
-- second argument of False returns minus one for an invalid value,
-- and the non-negative pos value for a valid value, so the
-- expansion of X'Valid is simply:
-- type(X)'Pos (X) >= 0
-- We can't quite generate it that way because of the requirement
-- for the non-standard second argument of False in the resulting
-- rep_to_pos call, so we have to explicitly create:
-- _rep_to_pos (X, False) >= 0
-- If we have an enumeration subtype, we also check that the
-- value is in range:
-- _rep_to_pos (X, False) >= 0
-- and then
-- (X >= type(X)'First and then type(X)'Last <= X)
elsif Is_Enumeration_Type (Ptyp)
and then Present (Enum_Pos_To_Rep (PBtyp))
then
Tst :=
Make_Op_Ge (Loc,
Left_Opnd =>
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (TSS (PBtyp, TSS_Rep_To_Pos), Loc),
Parameter_Associations => New_List (
Pref,
New_Occurrence_Of (Standard_False, Loc))),
Right_Opnd => Make_Integer_Literal (Loc, 0));
if Ptyp /= PBtyp
and then
(Type_Low_Bound (Ptyp) /= Type_Low_Bound (PBtyp)
or else
Type_High_Bound (Ptyp) /= Type_High_Bound (PBtyp))
then
-- The call to Make_Range_Test will create declarations
-- that need a proper insertion point, but Pref is now
-- attached to a node with no ancestor. Attach to tree
-- even if it is to be rewritten below.
Set_Parent (Tst, Parent (N));
Tst :=
Make_And_Then (Loc,
Left_Opnd => Make_Range_Test,
Right_Opnd => Tst);
end if;
Rewrite (N, Tst);
-- Fortran convention booleans
-- For the very special case of Fortran convention booleans, the
-- value is always valid, since it is an integer with the semantics
-- that non-zero is true, and any value is permissible.
elsif Is_Boolean_Type (Ptyp)
and then Convention (Ptyp) = Convention_Fortran
then
Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
-- For biased representations, we will be doing an unchecked
-- conversion without unbiasing the result. That means that the range
-- test has to take this into account, and the proper form of the
-- test is:
-- PBtyp!(Pref) < PBtyp!(Ptyp'Range_Length)
elsif Has_Biased_Representation (Ptyp) then
PBtyp := RTE (RE_Unsigned_32);
Rewrite (N,
Make_Op_Lt (Loc,
Left_Opnd =>
Unchecked_Convert_To (PBtyp, Duplicate_Subexpr (Pref)),
Right_Opnd =>
Unchecked_Convert_To (PBtyp,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Ptyp, Loc),
Attribute_Name => Name_Range_Length))));
-- For all other scalar types, what we want logically is a
-- range test:
-- X in type(X)'First .. type(X)'Last
-- But that's precisely what won't work because of possible
-- unwanted optimization (and indeed the basic motivation for
-- the Valid attribute is exactly that this test does not work).
-- What will work is:
-- PBtyp!(X) >= PBtyp!(type(X)'First)
-- and then
-- PBtyp!(X) <= PBtyp!(type(X)'Last)
-- where PBtyp is an integer type large enough to cover the full
-- range of possible stored values (i.e. it is chosen on the basis
-- of the size of the type, not the range of the values). We write
-- this as two tests, rather than a range check, so that static
-- evaluation will easily remove either or both of the checks if
-- they can be statically determined to be true (this happens
-- when the type of X is static and the range extends to the full
-- range of stored values).
-- Unsigned types. Note: it is safe to consider only whether the
-- subtype is unsigned, since we will in that case be doing all
-- unsigned comparisons based on the subtype range. Since we use the
-- actual subtype object size, this is appropriate.
-- For example, if we have
-- subtype x is integer range 1 .. 200;
-- for x'Object_Size use 8;
-- Now the base type is signed, but objects of this type are bits
-- unsigned, and doing an unsigned test of the range 1 to 200 is
-- correct, even though a value greater than 127 looks signed to a
-- signed comparison.
else
declare
Uns : constant Boolean :=
Is_Unsigned_Type (Ptyp)
or else (Is_Private_Type (Ptyp)
and then Is_Unsigned_Type (Btyp));
Size : Uint;
P : Node_Id := Pref;
begin
-- If the prefix is an object, use the Esize from this object
-- to handle in a more user friendly way the case of objects
-- or components with a large Size aspect: if a Size aspect is
-- specified, we want to read a scalar value as large as the
-- Size, unless the Size is larger than
-- System_Max_Integer_Size.
if Nkind (P) = N_Selected_Component then
P := Selector_Name (P);
end if;
if Nkind (P) in N_Has_Entity
and then Present (Entity (P))
and then Is_Object (Entity (P))
and then Known_Esize (Entity (P))
then
if Esize (Entity (P)) <= System_Max_Integer_Size then
Size := Esize (Entity (P));
else
Size := UI_From_Int (System_Max_Integer_Size);
end if;
else
Size := Esize (Ptyp);
end if;
PBtyp := Small_Integer_Type_For (Size, Uns);
Rewrite (N, Make_Range_Test);
end;
end if;
-- If a predicate is present, then we do the predicate test, even if
-- within the predicate function (infinite recursion is warned about
-- in Sem_Attr in that case).
declare
Pred_Func : constant Entity_Id := Predicate_Function (Ptyp);
begin
if Present (Pred_Func) then
Rewrite (N,
Make_And_Then (Loc,
Left_Opnd => Relocate_Node (N),
Right_Opnd => Make_Predicate_Call (Ptyp, Pref)));
end if;
end;
Analyze_And_Resolve (N, Standard_Boolean);
Validity_Checks_On := Save_Validity_Checks_On;
end Valid;
-----------------
-- Valid_Value --
-----------------
when Attribute_Valid_Value =>
Exp_Imgv.Expand_Valid_Value_Attribute (N);
-------------------
-- Valid_Scalars --
-------------------
when Attribute_Valid_Scalars => Valid_Scalars : declare
Val_Typ : constant Entity_Id := Validated_View (Ptyp);
Expr : Node_Id;
begin
-- Assume that the prefix does not need validation
Expr := Empty;
-- Attribute 'Valid_Scalars is not supported on private tagged types;
-- see a detailed explanation where this attribute is analyzed.
if Is_Private_Type (Ptyp) and then Is_Tagged_Type (Ptyp) then
null;
-- Attribute 'Valid_Scalars evaluates to True when the type lacks
-- scalars.
elsif not Scalar_Part_Present (Val_Typ) then
null;
-- Attribute 'Valid_Scalars is the same as attribute 'Valid when the
-- validated type is a scalar type. Generate:
-- Val_Typ (Pref)'Valid
elsif Is_Scalar_Type (Val_Typ) then
Expr :=
Make_Attribute_Reference (Loc,
Prefix =>
Unchecked_Convert_To (Val_Typ, New_Copy_Tree (Pref)),
Attribute_Name => Name_Valid);
-- Required by LLVM although the sizes are the same???
if Nkind (Prefix (Expr)) = N_Unchecked_Type_Conversion then
Set_No_Truncation (Prefix (Expr));
end if;
-- Validate the scalar components of an array by iterating over all
-- dimensions of the array while checking individual components.
elsif Is_Array_Type (Val_Typ) then
Expr :=
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of
(Build_Array_VS_Func
(Attr => N,
Formal_Typ => Ptyp,
Array_Typ => Val_Typ),
Loc),
Parameter_Associations => New_List (Pref));
-- Validate the scalar components, discriminants of a record type by
-- examining the structure of a record type.
elsif Is_Record_Type (Val_Typ) then
Expr :=
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of
(Build_Record_VS_Func
(Attr => N,
Formal_Typ => Ptyp,
Rec_Typ => Val_Typ),
Loc),
Parameter_Associations => New_List (Pref));
end if;
-- Default the attribute to True when the type of the prefix does not
-- need validation.
if No (Expr) then
Expr := New_Occurrence_Of (Standard_True, Loc);
end if;
Rewrite (N, Expr);
Analyze_And_Resolve (N, Standard_Boolean);
Set_Is_Static_Expression (N, False);
end Valid_Scalars;
-----------
-- Value --
-----------
when Attribute_Value =>
Exp_Imgv.Expand_Value_Attribute (N);
-----------------
-- Value_Size --
-----------------
-- The processing for Value_Size shares the processing for Size
-------------
-- Version --
-------------
-- The processing for Version shares the processing for Body_Version
----------------
-- Wide_Image --
----------------
when Attribute_Wide_Image =>
-- Leave attribute unexpanded in CodePeer mode: the gnat2scil
-- back-end knows how to handle this attribute directly.
if CodePeer_Mode then
return;
end if;
Exp_Imgv.Expand_Wide_Image_Attribute (N);
---------------------
-- Wide_Wide_Image --
---------------------
when Attribute_Wide_Wide_Image =>
-- Leave attribute unexpanded in CodePeer mode: the gnat2scil
-- back-end knows how to handle this attribute directly.
if CodePeer_Mode then
return;
end if;
Exp_Imgv.Expand_Wide_Wide_Image_Attribute (N);
----------------
-- Wide_Value --
----------------
-- We expand typ'Wide_Value (X) into
-- typ'Value
-- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
-- Wide_String_To_String is a runtime function that converts its wide
-- string argument to String, converting any non-translatable characters
-- into appropriate escape sequences. This preserves the required
-- semantics of Wide_Value in all cases, and results in a very simple
-- implementation approach.
-- Note: for this approach to be fully standard compliant for the cases
-- where typ is Wide_Character and Wide_Wide_Character, the encoding
-- method must cover the entire character range (e.g. UTF-8). But that
-- is a reasonable requirement when dealing with encoded character
-- sequences. Presumably if one of the restrictive encoding mechanisms
-- is in use such as Shift-JIS, then characters that cannot be
-- represented using this encoding will not appear in any case.
when Attribute_Wide_Value =>
Rewrite (N,
Make_Attribute_Reference (Loc,
Prefix => Pref,
Attribute_Name => Name_Value,
Expressions => New_List (
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of (RTE (RE_Wide_String_To_String), Loc),
Parameter_Associations => New_List (
Relocate_Node (First (Exprs)),
Make_Integer_Literal (Loc,
Intval => Int (Wide_Character_Encoding_Method)))))));
Analyze_And_Resolve (N, Typ);
---------------------
-- Wide_Wide_Value --
---------------------
-- We expand typ'Wide_Value_Value (X) into
-- typ'Value
-- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
-- See Wide_Value for more information. This is not quite right where
-- typ = Wide_Wide_Character, because the encoding method may not cover
-- the whole character type.
when Attribute_Wide_Wide_Value =>
Rewrite (N,
Make_Attribute_Reference (Loc,
Prefix => Pref,
Attribute_Name => Name_Value,
Expressions => New_List (
Make_Function_Call (Loc,
Name =>
New_Occurrence_Of
(RTE (RE_Wide_Wide_String_To_String), Loc),
Parameter_Associations => New_List (
Relocate_Node (First (Exprs)),
Make_Integer_Literal (Loc,
Intval => Int (Wide_Character_Encoding_Method)))))));
Analyze_And_Resolve (N, Typ);
---------------------
-- Wide_Wide_Width --
---------------------
when Attribute_Wide_Wide_Width =>
Exp_Imgv.Expand_Width_Attribute (N, Wide_Wide);
----------------
-- Wide_Width --
----------------
when Attribute_Wide_Width =>
Exp_Imgv.Expand_Width_Attribute (N, Wide);
-----------
-- Width --
-----------
when Attribute_Width =>
Exp_Imgv.Expand_Width_Attribute (N, Normal);
-----------
-- Write --
-----------
when Attribute_Write => Write : declare
P_Type : constant Entity_Id := Entity (Pref);
U_Type : constant Entity_Id := Underlying_Type (P_Type);
Pname : Entity_Id;
Decl : Node_Id;
Prag : Node_Id;
Arg3 : Node_Id;
Wfunc : Node_Id;
begin
-- If no underlying type, we have an error that will be diagnosed
-- elsewhere, so here we just completely ignore the expansion.
if No (U_Type) then
return;
end if;
-- Stream operations can appear in user code even if the restriction
-- No_Streams is active (for example, when instantiating a predefined
-- container). In that case rewrite the attribute as a Raise to
-- prevent any run-time use.
if Restriction_Active (No_Streams) then
Rewrite (N,
Make_Raise_Program_Error (Sloc (N),
Reason => PE_Stream_Operation_Not_Allowed));
Set_Etype (N, U_Type);
return;
end if;
-- The simple case, if there is a TSS for Write, just call it
Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Write);
if Present (Pname) then
null;
else
-- If there is a Stream_Convert pragma, use it, we rewrite
-- sourcetyp'Output (stream, Item)
-- as
-- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
-- where strmwrite is the given Write function that converts an
-- argument of type sourcetyp or a type acctyp, from which it is
-- derived to type strmtyp. The conversion to acttyp is required
-- for the derived case.
Prag := Get_Stream_Convert_Pragma (P_Type);
if Present (Prag) then
Arg3 :=
Next (Next (First (Pragma_Argument_Associations (Prag))));
Wfunc := Entity (Expression (Arg3));
Rewrite (N,
Make_Attribute_Reference (Loc,
Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
Attribute_Name => Name_Output,
Expressions => New_List (
Relocate_Node (First (Exprs)),
Make_Function_Call (Loc,
Name => New_Occurrence_Of (Wfunc, Loc),
Parameter_Associations => New_List (
OK_Convert_To (Etype (First_Formal (Wfunc)),
Relocate_Node (Next (First (Exprs)))))))));
Analyze (N);
return;
-- Limited types
elsif Default_Streaming_Unavailable (U_Type) then
-- Do the same thing here as is done above in the
-- case where a No_Streams restriction is active.
Rewrite (N,
Make_Raise_Program_Error (Sloc (N),
Reason => PE_Stream_Operation_Not_Allowed));
Set_Etype (N, U_Type);
return;
-- For elementary types, we call the W_xxx routine directly
elsif Is_Elementary_Type (U_Type) then
Rewrite (N, Build_Elementary_Write_Call (N));
Analyze (N);
return;
-- Array type case
elsif Is_Array_Type (U_Type) then
Build_Array_Write_Procedure (N, U_Type, Decl, Pname);
Compile_Stream_Body_In_Scope (N, Decl, U_Type);
-- Tagged type case, use the primitive Write function. Note that
-- this will dispatch in the class-wide case which is what we want
elsif Is_Tagged_Type (U_Type) then
Pname := Find_Prim_Op (U_Type, TSS_Stream_Write);
-- All other record type cases, including protected records.
-- The latter only arise for expander generated code for
-- handling shared passive partition access.
else
pragma Assert
(Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
-- Ada 2005 (AI-216): Program_Error is raised when executing
-- the default implementation of the Write attribute of an
-- Unchecked_Union type. However, if the 'Write reference is
-- within the generated Output stream procedure, Write outputs
-- the components, and the default values of the discriminant
-- are streamed by the Output procedure itself. If there are
-- no default values this is also erroneous.
if Is_Unchecked_Union (Base_Type (U_Type)) then
if (not Is_TSS (Current_Scope, TSS_Stream_Output)
and not Is_TSS (Current_Scope, TSS_Stream_Write))
or else No (Discriminant_Default_Value
(First_Discriminant (U_Type)))
then
Rewrite (N,
Make_Raise_Program_Error (Loc,
Reason => PE_Unchecked_Union_Restriction));
Set_Etype (N, U_Type);
return;
end if;
end if;
if Has_Defaulted_Discriminants (U_Type) then
Build_Mutable_Record_Write_Procedure
(Loc, Full_Base (U_Type), Decl, Pname);
else
Build_Record_Write_Procedure
(Loc, Full_Base (U_Type), Decl, Pname);
end if;
Insert_Action (N, Decl);
end if;
end if;
-- If we fall through, Pname is the procedure to be called
Rewrite_Attribute_Proc_Call (Pname);
end Write;
-- The following attributes are handled by the back end (except that
-- static cases have already been evaluated during semantic processing,
-- but in any case the back end should not count on this).
when Attribute_Code_Address
| Attribute_Deref
| Attribute_Null_Parameter
| Attribute_Passed_By_Reference
| Attribute_Pool_Address
=>
null;
-- The following attributes should not appear at this stage, since they
-- have already been handled by the analyzer (and properly rewritten
-- with corresponding values or entities to represent the right values).
when Attribute_Abort_Signal
| Attribute_Address_Size
| Attribute_Aft
| Attribute_Atomic_Always_Lock_Free
| Attribute_Base
| Attribute_Bit_Order
| Attribute_Class
| Attribute_Compiler_Version
| Attribute_Default_Bit_Order
| Attribute_Default_Scalar_Storage_Order
| Attribute_Definite
| Attribute_Delta
| Attribute_Denorm
| Attribute_Digits
| Attribute_Emax
| Attribute_Enabled
| Attribute_Epsilon
| Attribute_Fast_Math
| Attribute_First_Valid
| Attribute_Has_Access_Values
| Attribute_Has_Discriminants
| Attribute_Has_Tagged_Values
| Attribute_Large
| Attribute_Last_Valid
| Attribute_Library_Level
| Attribute_Lock_Free
| Attribute_Machine_Emax
| Attribute_Machine_Emin
| Attribute_Machine_Mantissa
| Attribute_Machine_Overflows
| Attribute_Machine_Radix
| Attribute_Machine_Rounds
| Attribute_Max_Alignment_For_Allocation
| Attribute_Max_Integer_Size
| Attribute_Maximum_Alignment
| Attribute_Model_Emin
| Attribute_Model_Epsilon
| Attribute_Model_Mantissa
| Attribute_Model_Small
| Attribute_Modulus
| Attribute_Partition_ID
| Attribute_Range
| Attribute_Restriction_Set
| Attribute_Safe_Emax
| Attribute_Safe_First
| Attribute_Safe_Large
| Attribute_Safe_Last
| Attribute_Safe_Small
| Attribute_Scalar_Storage_Order
| Attribute_Scale
| Attribute_Signed_Zeros
| Attribute_Small
| Attribute_Small_Denominator
| Attribute_Small_Numerator
| Attribute_Storage_Unit
| Attribute_Stub_Type
| Attribute_System_Allocator_Alignment
| Attribute_Target_Name
| Attribute_Type_Class
| Attribute_Type_Key
| Attribute_Unconstrained_Array
| Attribute_Universal_Literal_String
| Attribute_Wchar_T_Size
| Attribute_Word_Size
=>
raise Program_Error;
end case;
-- Note: as mentioned earlier, individual sections of the above case
-- statement assume there is no code after the case statement, and are
-- legitimately allowed to execute return statements if they have nothing
-- more to do, so DO NOT add code at this point.
exception
when RE_Not_Available =>
return;
end Expand_N_Attribute_Reference;
--------------------------------
-- Expand_Pred_Succ_Attribute --
--------------------------------
-- For typ'Pred (exp), we generate the check
-- [constraint_error when exp = typ'Base'First]
-- Similarly, for typ'Succ (exp), we generate the check
-- [constraint_error when exp = typ'Base'Last]
-- These checks are not generated for modular types, since the proper
-- semantics for Succ and Pred on modular types is to wrap, not raise CE.
-- We also suppress these checks if we are the right side of an assignment
-- statement or the expression of an object declaration, where the flag
-- Suppress_Assignment_Checks is set for the assignment/declaration.
procedure Expand_Pred_Succ_Attribute (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
P : constant Node_Id := Parent (N);
Cnam : Name_Id;
begin
if Attribute_Name (N) = Name_Pred then
Cnam := Name_First;
else
Cnam := Name_Last;
end if;
if Nkind (P) not in N_Assignment_Statement | N_Object_Declaration
or else not Suppress_Assignment_Checks (P)
then
Insert_Action (N,
Make_Raise_Constraint_Error (Loc,
Condition =>
Make_Op_Eq (Loc,
Left_Opnd =>
Duplicate_Subexpr_Move_Checks (First (Expressions (N))),
Right_Opnd =>
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Base_Type (Etype (Prefix (N))), Loc),
Attribute_Name => Cnam)),
Reason => CE_Overflow_Check_Failed));
end if;
end Expand_Pred_Succ_Attribute;
---------------------------
-- Expand_Size_Attribute --
---------------------------
procedure Expand_Size_Attribute (N : Node_Id) is
Loc : constant Source_Ptr := Sloc (N);
Typ : constant Entity_Id := Etype (N);
Pref : constant Node_Id := Prefix (N);
Ptyp : constant Entity_Id := Etype (Pref);
Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
Siz : Uint;
begin
-- Case of known RM_Size of a type
if Id in Attribute_Size | Attribute_Value_Size
and then Is_Entity_Name (Pref)
and then Is_Type (Entity (Pref))
and then Known_Static_RM_Size (Entity (Pref))
then
Siz := RM_Size (Entity (Pref));
-- Case of known Esize of a type
elsif Id = Attribute_Object_Size
and then Is_Entity_Name (Pref)
and then Is_Type (Entity (Pref))
and then Known_Static_Esize (Entity (Pref))
then
Siz := Esize (Entity (Pref));
-- Case of known size of object
elsif Id = Attribute_Size
and then Is_Entity_Name (Pref)
and then Is_Object (Entity (Pref))
and then Known_Static_Esize (Entity (Pref))
then
Siz := Esize (Entity (Pref));
-- For an array component, we can do Size in the front end if the
-- component_size of the array is set.
elsif Nkind (Pref) = N_Indexed_Component then
Siz := Component_Size (Etype (Prefix (Pref)));
-- For a record component, we can do Size in the front end if there is a
-- component clause, or if the record is packed and the component's size
-- is known at compile time.
elsif Nkind (Pref) = N_Selected_Component then
declare
Rec : constant Entity_Id := Etype (Prefix (Pref));
Comp : constant Entity_Id := Entity (Selector_Name (Pref));
begin
if Present (Component_Clause (Comp)) then
Siz := Esize (Comp);
elsif Is_Packed (Rec) then
Siz := RM_Size (Ptyp);
else
Apply_Universal_Integer_Attribute_Checks (N);
return;
end if;
end;
-- All other cases are handled by the back end
else
-- If Size is applied to a formal parameter that is of a packed
-- array subtype, then apply Size to the actual subtype.
if Is_Entity_Name (Pref)
and then Is_Formal (Entity (Pref))
and then Is_Packed_Array (Ptyp)
then
Rewrite (N,
Make_Attribute_Reference (Loc,
Prefix =>
New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc),
Attribute_Name => Name_Size));
Analyze_And_Resolve (N, Typ);
-- If Size is applied to a dereference of an access to unconstrained
-- packed array, the back end needs to see its unconstrained nominal
-- type, but also a hint to the actual constrained type.
elsif Nkind (Pref) = N_Explicit_Dereference
and then Is_Packed_Array (Ptyp)
and then not Is_Constrained (Ptyp)
then
Set_Actual_Designated_Subtype (Pref, Get_Actual_Subtype (Pref));
-- If Size was applied to a slice of a bit-packed array, we rewrite
-- it into the product of Length and Component_Size. We need to do so
-- because bit-packed arrays are represented internally as arrays of
-- System.Unsigned_Types.Packed_Byte for code generation purposes so
-- the size is always rounded up in the back end.
elsif Nkind (Pref) = N_Slice and then Is_Bit_Packed_Array (Ptyp) then
Rewrite (N,
Make_Op_Multiply (Loc,
Make_Attribute_Reference (Loc,
Prefix => Duplicate_Subexpr (Pref, True),
Attribute_Name => Name_Length),
Make_Attribute_Reference (Loc,
Prefix => Duplicate_Subexpr (Pref, True),
Attribute_Name => Name_Component_Size)));
Analyze_And_Resolve (N, Typ);
end if;
-- Apply the required checks last, after rewriting has taken place
Apply_Universal_Integer_Attribute_Checks (N);
return;
end if;
-- Common processing for record and array component case
if Present (Siz) and then Siz /= 0 then
declare
CS : constant Boolean := Comes_From_Source (N);
begin
Rewrite (N, Make_Integer_Literal (Loc, Siz));
-- This integer literal is not a static expression. We do not
-- call Analyze_And_Resolve here, because this would activate
-- the circuit for deciding that a static value was out of range,
-- and we don't want that.
-- So just manually set the type, mark the expression as
-- nonstatic, and then ensure that the result is checked
-- properly if the attribute comes from source (if it was
-- internally generated, we never need a constraint check).
Set_Etype (N, Typ);
Set_Is_Static_Expression (N, False);
if CS then
Apply_Constraint_Check (N, Typ);
end if;
end;
end if;
end Expand_Size_Attribute;
-----------------------------
-- Expand_Update_Attribute --
-----------------------------
procedure Expand_Update_Attribute (N : Node_Id) is
procedure Process_Component_Or_Element_Update
(Temp : Entity_Id;
Comp : Node_Id;
Expr : Node_Id;
Typ : Entity_Id);
-- Generate the statements necessary to update a single component or an
-- element of the prefix. The code is inserted before the attribute N.
-- Temp denotes the entity of the anonymous object created to reflect
-- the changes in values. Comp is the component/index expression to be
-- updated. Expr is an expression yielding the new value of Comp. Typ
-- is the type of the prefix of attribute Update.
procedure Process_Range_Update
(Temp : Entity_Id;
Comp : Node_Id;
Expr : Node_Id;
Typ : Entity_Id);
-- Generate the statements necessary to update a slice of the prefix.
-- The code is inserted before the attribute N. Temp denotes the entity
-- of the anonymous object created to reflect the changes in values.
-- Comp is range of the slice to be updated. Expr is an expression
-- yielding the new value of Comp. Typ is the type of the prefix of
-- attribute Update.
-----------------------------------------
-- Process_Component_Or_Element_Update --
-----------------------------------------
procedure Process_Component_Or_Element_Update
(Temp : Entity_Id;
Comp : Node_Id;
Expr : Node_Id;
Typ : Entity_Id)
is
Loc : constant Source_Ptr := Sloc (Comp);
Exprs : List_Id;
LHS : Node_Id;
begin
-- An array element may be modified by the following relations
-- depending on the number of dimensions:
-- 1 => Expr -- one dimensional update
-- (1, ..., N) => Expr -- multi dimensional update
-- The above forms are converted in assignment statements where the
-- left hand side is an indexed component:
-- Temp (1) := Expr; -- one dimensional update
-- Temp (1, ..., N) := Expr; -- multi dimensional update
if Is_Array_Type (Typ) then
-- The index expressions of a multi dimensional array update
-- appear as an aggregate.
if Nkind (Comp) = N_Aggregate then
Exprs := New_Copy_List_Tree (Expressions (Comp));
else
Exprs := New_List (Relocate_Node (Comp));
end if;
LHS :=
Make_Indexed_Component (Loc,
Prefix => New_Occurrence_Of (Temp, Loc),
Expressions => Exprs);
-- A record component update appears in the following form:
-- Comp => Expr
-- The above relation is transformed into an assignment statement
-- where the left hand side is a selected component:
-- Temp.Comp := Expr;
else pragma Assert (Is_Record_Type (Typ));
LHS :=
Make_Selected_Component (Loc,
Prefix => New_Occurrence_Of (Temp, Loc),
Selector_Name => Relocate_Node (Comp));
end if;
Insert_Action (N,
Make_Assignment_Statement (Loc,
Name => LHS,
Expression => Relocate_Node (Expr)));
end Process_Component_Or_Element_Update;
--------------------------
-- Process_Range_Update --
--------------------------
procedure Process_Range_Update
(Temp : Entity_Id;
Comp : Node_Id;
Expr : Node_Id;
Typ : Entity_Id)
is
Index_Typ : constant Entity_Id := Etype (First_Index (Typ));
Loc : constant Source_Ptr := Sloc (Comp);
Index : Entity_Id;
begin
-- A range update appears as
-- (Low .. High => Expr)
-- The above construct is transformed into a loop that iterates over
-- the given range and modifies the corresponding array values to the
-- value of Expr:
-- for Index in Low .. High loop
-- Temp (<Index_Typ> (Index)) := Expr;
-- end loop;
Index := Make_Temporary (Loc, 'I');
Insert_Action (N,
Make_Loop_Statement (Loc,
Iteration_Scheme =>
Make_Iteration_Scheme (Loc,
Loop_Parameter_Specification =>
Make_Loop_Parameter_Specification (Loc,
Defining_Identifier => Index,
Discrete_Subtype_Definition => Relocate_Node (Comp))),
Statements => New_List (
Make_Assignment_Statement (Loc,
Name =>
Make_Indexed_Component (Loc,
Prefix => New_Occurrence_Of (Temp, Loc),
Expressions => New_List (
Convert_To (Index_Typ,
New_Occurrence_Of (Index, Loc)))),
Expression => Relocate_Node (Expr))),
End_Label => Empty));
end Process_Range_Update;
-- Local variables
Aggr : constant Node_Id := First (Expressions (N));
Loc : constant Source_Ptr := Sloc (N);
Pref : constant Node_Id := Prefix (N);
Typ : constant Entity_Id := Etype (Pref);
Assoc : Node_Id;
Comp : Node_Id;
CW_Temp : Entity_Id;
CW_Typ : Entity_Id;
Expr : Node_Id;
Temp : Entity_Id;
-- Start of processing for Expand_Update_Attribute
begin
-- Create the anonymous object to store the value of the prefix and
-- capture subsequent changes in value.
Temp := Make_Temporary (Loc, 'T', Pref);
-- Preserve the tag of the prefix by offering a specific view of the
-- class-wide version of the prefix.
if Is_Tagged_Type (Typ) then
-- Generate:
-- CW_Temp : Typ'Class := Typ'Class (Pref);
CW_Temp := Make_Temporary (Loc, 'T');
CW_Typ := Class_Wide_Type (Typ);
Insert_Action (N,
Make_Object_Declaration (Loc,
Defining_Identifier => CW_Temp,
Object_Definition => New_Occurrence_Of (CW_Typ, Loc),
Expression =>
Convert_To (CW_Typ, Relocate_Node (Pref))));
-- Generate:
-- Temp : Typ renames Typ (CW_Temp);
Insert_Action (N,
Make_Object_Renaming_Declaration (Loc,
Defining_Identifier => Temp,
Subtype_Mark => New_Occurrence_Of (Typ, Loc),
Name =>
Convert_To (Typ, New_Occurrence_Of (CW_Temp, Loc))));
-- Non-tagged case
else
-- Generate:
-- Temp : Typ := Pref;
Insert_Action (N,
Make_Object_Declaration (Loc,
Defining_Identifier => Temp,
Object_Definition => New_Occurrence_Of (Typ, Loc),
Expression => Relocate_Node (Pref)));
end if;
-- Process the update aggregate
Assoc := First (Component_Associations (Aggr));
while Present (Assoc) loop
Comp := First (Choices (Assoc));
Expr := Expression (Assoc);
while Present (Comp) loop
if Nkind (Comp) = N_Range then
Process_Range_Update (Temp, Comp, Expr, Typ);
elsif Nkind (Comp) = N_Subtype_Indication then
Process_Range_Update
(Temp, Range_Expression (Constraint (Comp)), Expr, Typ);
else
Process_Component_Or_Element_Update (Temp, Comp, Expr, Typ);
end if;
Next (Comp);
end loop;
Next (Assoc);
end loop;
-- The attribute is replaced by a reference to the anonymous object
Rewrite (N, New_Occurrence_Of (Temp, Loc));
Analyze (N);
end Expand_Update_Attribute;
-------------------
-- Find_Fat_Info --
-------------------
procedure Find_Fat_Info
(T : Entity_Id;
Fat_Type : out Entity_Id;
Fat_Pkg : out RE_Id)
is
Rtyp : constant Entity_Id := Root_Type (T);
begin
-- All we do is use the root type (historically this dealt with
-- VAX-float .. to be cleaned up further later ???)
if Rtyp = Standard_Short_Float or else Rtyp = Standard_Float then
Fat_Type := Standard_Float;
Fat_Pkg := RE_Attr_Float;
elsif Rtyp = Standard_Long_Float then
Fat_Type := Standard_Long_Float;
Fat_Pkg := RE_Attr_Long_Float;
elsif Rtyp = Standard_Long_Long_Float then
Fat_Type := Standard_Long_Long_Float;
Fat_Pkg := RE_Attr_Long_Long_Float;
-- Universal real (which is its own root type) is treated as being
-- equivalent to Standard.Long_Long_Float, since it is defined to
-- have the same precision as the longest Float type.
elsif Rtyp = Universal_Real then
Fat_Type := Standard_Long_Long_Float;
Fat_Pkg := RE_Attr_Long_Long_Float;
else
raise Program_Error;
end if;
end Find_Fat_Info;
----------------------------
-- Find_Stream_Subprogram --
----------------------------
function Find_Stream_Subprogram
(Typ : Entity_Id;
Nam : TSS_Name_Type) return Entity_Id
is
Base_Typ : constant Entity_Id := Base_Type (Typ);
Ent : constant Entity_Id := TSS (Typ, Nam);
begin
if Present (Ent) then
return Ent;
end if;
-- Stream attributes for strings are expanded into library calls. The
-- following checks are disabled when the run-time is not available or
-- when compiling predefined types due to bootstrap issues. As a result,
-- the compiler will generate in-place stream routines for string types
-- that appear in GNAT's library, but will generate calls via rtsfind
-- to library routines for user code.
-- Note: In the case of using a configurable run time, it is very likely
-- that stream routines for string types are not present (they require
-- file system support). In this case, the specific stream routines for
-- strings are not used, relying on the regular stream mechanism
-- instead. That is why we include the test RTE_Available when dealing
-- with these cases.
if not Is_Predefined_Unit (Current_Sem_Unit) then
-- Storage_Array as defined in package System.Storage_Elements
if Is_RTE (Base_Typ, RE_Storage_Array) then
-- Case of No_Stream_Optimizations restriction active
if Restriction_Active (No_Stream_Optimizations) then
if Nam = TSS_Stream_Input
and then RTE_Available (RE_Storage_Array_Input)
then
return RTE (RE_Storage_Array_Input);
elsif Nam = TSS_Stream_Output
and then RTE_Available (RE_Storage_Array_Output)
then
return RTE (RE_Storage_Array_Output);
elsif Nam = TSS_Stream_Read
and then RTE_Available (RE_Storage_Array_Read)
then
return RTE (RE_Storage_Array_Read);
elsif Nam = TSS_Stream_Write
and then RTE_Available (RE_Storage_Array_Write)
then
return RTE (RE_Storage_Array_Write);
elsif Nam /= TSS_Stream_Input and then
Nam /= TSS_Stream_Output and then
Nam /= TSS_Stream_Read and then
Nam /= TSS_Stream_Write
then
raise Program_Error;
end if;
-- Restriction No_Stream_Optimizations is not set, so we can go
-- ahead and optimize using the block IO forms of the routines.
else
if Nam = TSS_Stream_Input
and then RTE_Available (RE_Storage_Array_Input_Blk_IO)
then
return RTE (RE_Storage_Array_Input_Blk_IO);
elsif Nam = TSS_Stream_Output
and then RTE_Available (RE_Storage_Array_Output_Blk_IO)
then
return RTE (RE_Storage_Array_Output_Blk_IO);
elsif Nam = TSS_Stream_Read
and then RTE_Available (RE_Storage_Array_Read_Blk_IO)
then
return RTE (RE_Storage_Array_Read_Blk_IO);
elsif Nam = TSS_Stream_Write
and then RTE_Available (RE_Storage_Array_Write_Blk_IO)
then
return RTE (RE_Storage_Array_Write_Blk_IO);
elsif Nam /= TSS_Stream_Input and then
Nam /= TSS_Stream_Output and then
Nam /= TSS_Stream_Read and then
Nam /= TSS_Stream_Write
then
raise Program_Error;
end if;
end if;
-- Stream_Element_Array as defined in package Ada.Streams
elsif Is_RTE (Base_Typ, RE_Stream_Element_Array) then
-- Case of No_Stream_Optimizations restriction active
if Restriction_Active (No_Stream_Optimizations) then
if Nam = TSS_Stream_Input
and then RTE_Available (RE_Stream_Element_Array_Input)
then
return RTE (RE_Stream_Element_Array_Input);
elsif Nam = TSS_Stream_Output
and then RTE_Available (RE_Stream_Element_Array_Output)
then
return RTE (RE_Stream_Element_Array_Output);
elsif Nam = TSS_Stream_Read
and then RTE_Available (RE_Stream_Element_Array_Read)
then
return RTE (RE_Stream_Element_Array_Read);
elsif Nam = TSS_Stream_Write
and then RTE_Available (RE_Stream_Element_Array_Write)
then
return RTE (RE_Stream_Element_Array_Write);
elsif Nam /= TSS_Stream_Input and then
Nam /= TSS_Stream_Output and then
Nam /= TSS_Stream_Read and then
Nam /= TSS_Stream_Write
then
raise Program_Error;
end if;
-- Restriction No_Stream_Optimizations is not set, so we can go
-- ahead and optimize using the block IO forms of the routines.
else
if Nam = TSS_Stream_Input
and then RTE_Available (RE_Stream_Element_Array_Input_Blk_IO)
then
return RTE (RE_Stream_Element_Array_Input_Blk_IO);
elsif Nam = TSS_Stream_Output
and then RTE_Available (RE_Stream_Element_Array_Output_Blk_IO)
then
return RTE (RE_Stream_Element_Array_Output_Blk_IO);
elsif Nam = TSS_Stream_Read
and then RTE_Available (RE_Stream_Element_Array_Read_Blk_IO)
then
return RTE (RE_Stream_Element_Array_Read_Blk_IO);
elsif Nam = TSS_Stream_Write
and then RTE_Available (RE_Stream_Element_Array_Write_Blk_IO)
then
return RTE (RE_Stream_Element_Array_Write_Blk_IO);
elsif Nam /= TSS_Stream_Input and then
Nam /= TSS_Stream_Output and then
Nam /= TSS_Stream_Read and then
Nam /= TSS_Stream_Write
then
raise Program_Error;
end if;
end if;
-- String as defined in package Ada
elsif Base_Typ = Standard_String then
-- Case of No_Stream_Optimizations restriction active
if Restriction_Active (No_Stream_Optimizations) then
if Nam = TSS_Stream_Input
and then RTE_Available (RE_String_Input)
then
return RTE (RE_String_Input);
elsif Nam = TSS_Stream_Output
and then RTE_Available (RE_String_Output)
then
return RTE (RE_String_Output);
elsif Nam = TSS_Stream_Read
and then RTE_Available (RE_String_Read)
then
return RTE (RE_String_Read);
elsif Nam = TSS_Stream_Write
and then RTE_Available (RE_String_Write)
then
return RTE (RE_String_Write);
elsif Nam /= TSS_Stream_Input and then
Nam /= TSS_Stream_Output and then
Nam /= TSS_Stream_Read and then
Nam /= TSS_Stream_Write
then
raise Program_Error;
end if;
-- Restriction No_Stream_Optimizations is not set, so we can go
-- ahead and optimize using the block IO forms of the routines.
else
if Nam = TSS_Stream_Input
and then RTE_Available (RE_String_Input_Blk_IO)
then
return RTE (RE_String_Input_Blk_IO);
elsif Nam = TSS_Stream_Output
and then RTE_Available (RE_String_Output_Blk_IO)
then
return RTE (RE_String_Output_Blk_IO);
elsif Nam = TSS_Stream_Read
and then RTE_Available (RE_String_Read_Blk_IO)
then
return RTE (RE_String_Read_Blk_IO);
elsif Nam = TSS_Stream_Write
and then RTE_Available (RE_String_Write_Blk_IO)
then
return RTE (RE_String_Write_Blk_IO);
elsif Nam /= TSS_Stream_Input and then
Nam /= TSS_Stream_Output and then
Nam /= TSS_Stream_Read and then
Nam /= TSS_Stream_Write
then
raise Program_Error;
end if;
end if;
-- Wide_String as defined in package Ada
elsif Base_Typ = Standard_Wide_String then
-- Case of No_Stream_Optimizations restriction active
if Restriction_Active (No_Stream_Optimizations) then
if Nam = TSS_Stream_Input
and then RTE_Available (RE_Wide_String_Input)
then
return RTE (RE_Wide_String_Input);
elsif Nam = TSS_Stream_Output
and then RTE_Available (RE_Wide_String_Output)
then
return RTE (RE_Wide_String_Output);
elsif Nam = TSS_Stream_Read
and then RTE_Available (RE_Wide_String_Read)
then
return RTE (RE_Wide_String_Read);
elsif Nam = TSS_Stream_Write
and then RTE_Available (RE_Wide_String_Write)
then
return RTE (RE_Wide_String_Write);
elsif Nam /= TSS_Stream_Input and then
Nam /= TSS_Stream_Output and then
Nam /= TSS_Stream_Read and then
Nam /= TSS_Stream_Write
then
raise Program_Error;
end if;
-- Restriction No_Stream_Optimizations is not set, so we can go
-- ahead and optimize using the block IO forms of the routines.
else
if Nam = TSS_Stream_Input
and then RTE_Available (RE_Wide_String_Input_Blk_IO)
then
return RTE (RE_Wide_String_Input_Blk_IO);
elsif Nam = TSS_Stream_Output
and then RTE_Available (RE_Wide_String_Output_Blk_IO)
then
return RTE (RE_Wide_String_Output_Blk_IO);
elsif Nam = TSS_Stream_Read
and then RTE_Available (RE_Wide_String_Read_Blk_IO)
then
return RTE (RE_Wide_String_Read_Blk_IO);
elsif Nam = TSS_Stream_Write
and then RTE_Available (RE_Wide_String_Write_Blk_IO)
then
return RTE (RE_Wide_String_Write_Blk_IO);
elsif Nam /= TSS_Stream_Input and then
Nam /= TSS_Stream_Output and then
Nam /= TSS_Stream_Read and then
Nam /= TSS_Stream_Write
then
raise Program_Error;
end if;
end if;
-- Wide_Wide_String as defined in package Ada
elsif Base_Typ = Standard_Wide_Wide_String then
-- Case of No_Stream_Optimizations restriction active
if Restriction_Active (No_Stream_Optimizations) then
if Nam = TSS_Stream_Input
and then RTE_Available (RE_Wide_Wide_String_Input)
then
return RTE (RE_Wide_Wide_String_Input);
elsif Nam = TSS_Stream_Output
and then RTE_Available (RE_Wide_Wide_String_Output)
then
return RTE (RE_Wide_Wide_String_Output);
elsif Nam = TSS_Stream_Read
and then RTE_Available (RE_Wide_Wide_String_Read)
then
return RTE (RE_Wide_Wide_String_Read);
elsif Nam = TSS_Stream_Write
and then RTE_Available (RE_Wide_Wide_String_Write)
then
return RTE (RE_Wide_Wide_String_Write);
elsif Nam /= TSS_Stream_Input and then
Nam /= TSS_Stream_Output and then
Nam /= TSS_Stream_Read and then
Nam /= TSS_Stream_Write
then
raise Program_Error;
end if;
-- Restriction No_Stream_Optimizations is not set, so we can go
-- ahead and optimize using the block IO forms of the routines.
else
if Nam = TSS_Stream_Input
and then RTE_Available (RE_Wide_Wide_String_Input_Blk_IO)
then
return RTE (RE_Wide_Wide_String_Input_Blk_IO);
elsif Nam = TSS_Stream_Output
and then RTE_Available (RE_Wide_Wide_String_Output_Blk_IO)
then
return RTE (RE_Wide_Wide_String_Output_Blk_IO);
elsif Nam = TSS_Stream_Read
and then RTE_Available (RE_Wide_Wide_String_Read_Blk_IO)
then
return RTE (RE_Wide_Wide_String_Read_Blk_IO);
elsif Nam = TSS_Stream_Write
and then RTE_Available (RE_Wide_Wide_String_Write_Blk_IO)
then
return RTE (RE_Wide_Wide_String_Write_Blk_IO);
elsif Nam /= TSS_Stream_Input and then
Nam /= TSS_Stream_Output and then
Nam /= TSS_Stream_Read and then
Nam /= TSS_Stream_Write
then
raise Program_Error;
end if;
end if;
end if;
end if;
if Is_Tagged_Type (Typ) and then Is_Derived_Type (Typ) then
return Find_Prim_Op (Typ, Nam);
else
return Find_Inherited_TSS (Typ, Nam);
end if;
end Find_Stream_Subprogram;
---------------
-- Full_Base --
---------------
function Full_Base (T : Entity_Id) return Entity_Id is
BT : Entity_Id;
begin
BT := Base_Type (T);
if Is_Private_Type (BT)
and then Present (Full_View (BT))
then
BT := Full_View (BT);
end if;
return BT;
end Full_Base;
-------------------------------
-- Get_Stream_Convert_Pragma --
-------------------------------
function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id is
Typ : Entity_Id;
N : Node_Id;
begin
-- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
-- that a stream convert pragma for a tagged type is not inherited from
-- its parent. Probably what is wrong here is that it is basically
-- incorrect to consider a stream convert pragma to be a representation
-- pragma at all ???
N := First_Rep_Item (Implementation_Base_Type (T));
while Present (N) loop
if Nkind (N) = N_Pragma
and then Pragma_Name (N) = Name_Stream_Convert
then
-- For tagged types this pragma is not inherited, so we
-- must verify that it is defined for the given type and
-- not an ancestor.
Typ :=
Entity (Expression (First (Pragma_Argument_Associations (N))));
if not Is_Tagged_Type (T)
or else T = Typ
or else (Is_Private_Type (Typ) and then T = Full_View (Typ))
then
return N;
end if;
end if;
Next_Rep_Item (N);
end loop;
return Empty;
end Get_Stream_Convert_Pragma;
---------------------------------
-- Is_Constrained_Packed_Array --
---------------------------------
function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is
Arr : Entity_Id := Typ;
begin
if Is_Access_Type (Arr) then
Arr := Designated_Type (Arr);
end if;
return Is_Array_Type (Arr)
and then Is_Constrained (Arr)
and then Present (Packed_Array_Impl_Type (Arr));
end Is_Constrained_Packed_Array;
----------------------------------------
-- Is_Inline_Floating_Point_Attribute --
----------------------------------------
function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean is
Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
function Is_GCC_Target return Boolean;
-- Return True if we are using a GCC target/back-end
-- ??? Note: the implementation is kludgy/fragile
-------------------
-- Is_GCC_Target --
-------------------
function Is_GCC_Target return Boolean is
begin
return not CodePeer_Mode
and then not Modify_Tree_For_C;
end Is_GCC_Target;
-- Start of processing for Is_Inline_Floating_Point_Attribute
begin
-- Machine and Model can be expanded by the GCC back end only
if Id = Attribute_Machine or else Id = Attribute_Model then
return Is_GCC_Target;
-- Remaining cases handled by all back ends are Rounding and Truncation
-- when appearing as the operand of a conversion to some integer type.
elsif Nkind (Parent (N)) /= N_Type_Conversion
or else not Is_Integer_Type (Etype (Parent (N)))
then
return False;
end if;
-- Here we are in the integer conversion context. We reuse Rounding for
-- Machine_Rounding as System.Fat_Gen, which is a permissible behavior.
return
Id = Attribute_Rounding
or else Id = Attribute_Machine_Rounding
or else Id = Attribute_Truncation;
end Is_Inline_Floating_Point_Attribute;
end Exp_Attr;