1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Aspects; use Aspects;
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Exp_Atag; use Exp_Atag;
32 with Exp_Ch2; use Exp_Ch2;
33 with Exp_Ch3; use Exp_Ch3;
34 with Exp_Ch6; use Exp_Ch6;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Dist; use Exp_Dist;
37 with Exp_Imgv; use Exp_Imgv;
38 with Exp_Pakd; use Exp_Pakd;
39 with Exp_Strm; use Exp_Strm;
40 with Exp_Tss; use Exp_Tss;
41 with Exp_Util; use Exp_Util;
42 with Fname; use Fname;
43 with Freeze; use Freeze;
44 with Gnatvsn; use Gnatvsn;
45 with Itypes; use Itypes;
47 with Namet; use Namet;
48 with Nmake; use Nmake;
49 with Nlists; use Nlists;
51 with Restrict; use Restrict;
52 with Rident; use Rident;
53 with Rtsfind; use Rtsfind;
55 with Sem_Aux; use Sem_Aux;
56 with Sem_Ch6; use Sem_Ch6;
57 with Sem_Ch7; use Sem_Ch7;
58 with Sem_Ch8; use Sem_Ch8;
59 with Sem_Eval; use Sem_Eval;
60 with Sem_Res; use Sem_Res;
61 with Sem_Util; use Sem_Util;
62 with Sinfo; use Sinfo;
63 with Snames; use Snames;
64 with Stand; use Stand;
65 with Stringt; use Stringt;
66 with Targparm; use Targparm;
67 with Tbuild; use Tbuild;
68 with Ttypes; use Ttypes;
69 with Uintp; use Uintp;
70 with Uname; use Uname;
71 with Validsw; use Validsw;
73 package body Exp_Attr is
75 -----------------------
76 -- Local Subprograms --
77 -----------------------
79 function Build_Array_VS_Func
81 Nod : Node_Id) return Entity_Id;
82 -- Build function to test Valid_Scalars for array type A_Type. Nod is the
83 -- Valid_Scalars attribute node, used to insert the function body, and the
84 -- value returned is the entity of the constructed function body. We do not
85 -- bother to generate a separate spec for this subprogram.
87 function Build_Record_VS_Func
89 Nod : Node_Id) return Entity_Id;
90 -- Build function to test Valid_Scalars for record type A_Type. Nod is the
91 -- Valid_Scalars attribute node, used to insert the function body, and the
92 -- value returned is the entity of the constructed function body. We do not
93 -- bother to generate a separate spec for this subprogram.
95 procedure Compile_Stream_Body_In_Scope
100 -- The body for a stream subprogram may be generated outside of the scope
101 -- of the type. If the type is fully private, it may depend on the full
102 -- view of other types (e.g. indexes) that are currently private as well.
103 -- We install the declarations of the package in which the type is declared
104 -- before compiling the body in what is its proper environment. The Check
105 -- parameter indicates if checks are to be suppressed for the stream body.
106 -- We suppress checks for array/record reads, since the rule is that these
107 -- are like assignments, out of range values due to uninitialized storage,
108 -- or other invalid values do NOT cause a Constraint_Error to be raised.
109 -- If we are within an instance body all visibility has been established
110 -- already and there is no need to install the package.
112 procedure Expand_Access_To_Protected_Op
116 -- An attribute reference to a protected subprogram is transformed into
117 -- a pair of pointers: one to the object, and one to the operations.
118 -- This expansion is performed for 'Access and for 'Unrestricted_Access.
120 procedure Expand_Fpt_Attribute
125 -- This procedure expands a call to a floating-point attribute function.
126 -- N is the attribute reference node, and Args is a list of arguments to
127 -- be passed to the function call. Pkg identifies the package containing
128 -- the appropriate instantiation of System.Fat_Gen. Float arguments in Args
129 -- have already been converted to the floating-point type for which Pkg was
130 -- instantiated. The Nam argument is the relevant attribute processing
131 -- routine to be called. This is the same as the attribute name, except in
132 -- the Unaligned_Valid case.
134 procedure Expand_Fpt_Attribute_R (N : Node_Id);
135 -- This procedure expands a call to a floating-point attribute function
136 -- that takes a single floating-point argument. The function to be called
137 -- is always the same as the attribute name.
139 procedure Expand_Fpt_Attribute_RI (N : Node_Id);
140 -- This procedure expands a call to a floating-point attribute function
141 -- that takes one floating-point argument and one integer argument. The
142 -- function to be called is always the same as the attribute name.
144 procedure Expand_Fpt_Attribute_RR (N : Node_Id);
145 -- This procedure expands a call to a floating-point attribute function
146 -- that takes two floating-point arguments. The function to be called
147 -- is always the same as the attribute name.
149 procedure Expand_Loop_Entry_Attribute (N : Node_Id);
150 -- Handle the expansion of attribute 'Loop_Entry. As a result, the related
151 -- loop may be converted into a conditional block. See body for details.
153 procedure Expand_Min_Max_Attribute (N : Node_Id);
154 -- Handle the expansion of attributes 'Max and 'Min, including expanding
155 -- then out if we are in Modify_Tree_For_C mode.
157 procedure Expand_Pred_Succ_Attribute (N : Node_Id);
158 -- Handles expansion of Pred or Succ attributes for case of non-real
159 -- operand with overflow checking required.
161 procedure Expand_Update_Attribute (N : Node_Id);
162 -- Handle the expansion of attribute Update
164 function Get_Index_Subtype (N : Node_Id) return Entity_Id;
165 -- Used for Last, Last, and Length, when the prefix is an array type.
166 -- Obtains the corresponding index subtype.
168 procedure Find_Fat_Info
170 Fat_Type : out Entity_Id;
171 Fat_Pkg : out RE_Id);
172 -- Given a floating-point type T, identifies the package containing the
173 -- attributes for this type (returned in Fat_Pkg), and the corresponding
174 -- type for which this package was instantiated from Fat_Gen. Error if T
175 -- is not a floating-point type.
177 function Find_Stream_Subprogram
179 Nam : TSS_Name_Type) return Entity_Id;
180 -- Returns the stream-oriented subprogram attribute for Typ. For tagged
181 -- types, the corresponding primitive operation is looked up, else the
182 -- appropriate TSS from the type itself, or from its closest ancestor
183 -- defining it, is returned. In both cases, inheritance of representation
184 -- aspects is thus taken into account.
186 function Full_Base (T : Entity_Id) return Entity_Id;
187 -- The stream functions need to examine the underlying representation of
188 -- composite types. In some cases T may be non-private but its base type
189 -- is, in which case the function returns the corresponding full view.
191 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id;
192 -- Given a type, find a corresponding stream convert pragma that applies to
193 -- the implementation base type of this type (Typ). If found, return the
194 -- pragma node, otherwise return Empty if no pragma is found.
196 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean;
197 -- Utility for array attributes, returns true on packed constrained
198 -- arrays, and on access to same.
200 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean;
201 -- Returns true iff the given node refers to an attribute call that
202 -- can be expanded directly by the back end and does not need front end
203 -- expansion. Typically used for rounding and truncation attributes that
204 -- appear directly inside a conversion to integer.
206 -------------------------
207 -- Build_Array_VS_Func --
208 -------------------------
210 function Build_Array_VS_Func
212 Nod : Node_Id) return Entity_Id
214 Loc : constant Source_Ptr := Sloc (Nod);
215 Func_Id : constant Entity_Id := Make_Temporary (Loc, 'V');
216 Comp_Type : constant Entity_Id := Component_Type (A_Type);
217 Body_Stmts : List_Id;
218 Index_List : List_Id;
221 function Test_Component return List_Id;
222 -- Create one statement to test validity of one component designated by
223 -- a full set of indexes. Returns statement list containing test.
225 function Test_One_Dimension (N : Int) return List_Id;
226 -- Create loop to test one dimension of the array. The single statement
227 -- in the loop body tests the inner dimensions if any, or else the
228 -- single component. Note that this procedure is called recursively,
229 -- with N being the dimension to be initialized. A call with N greater
230 -- than the number of dimensions simply generates the component test,
231 -- terminating the recursion. Returns statement list containing tests.
237 function Test_Component return List_Id is
243 Make_Indexed_Component (Loc,
244 Prefix => Make_Identifier (Loc, Name_uA),
245 Expressions => Index_List);
247 if Is_Scalar_Type (Comp_Type) then
250 Anam := Name_Valid_Scalars;
254 Make_If_Statement (Loc,
258 Make_Attribute_Reference (Loc,
259 Attribute_Name => Anam,
261 Then_Statements => New_List (
262 Make_Simple_Return_Statement (Loc,
263 Expression => New_Occurrence_Of (Standard_False, Loc)))));
266 ------------------------
267 -- Test_One_Dimension --
268 ------------------------
270 function Test_One_Dimension (N : Int) return List_Id is
274 -- If all dimensions dealt with, we simply test the component
276 if N > Number_Dimensions (A_Type) then
277 return Test_Component;
279 -- Here we generate the required loop
283 Make_Defining_Identifier (Loc, New_External_Name ('J', N));
285 Append (New_Occurrence_Of (Index, Loc), Index_List);
288 Make_Implicit_Loop_Statement (Nod,
291 Make_Iteration_Scheme (Loc,
292 Loop_Parameter_Specification =>
293 Make_Loop_Parameter_Specification (Loc,
294 Defining_Identifier => Index,
295 Discrete_Subtype_Definition =>
296 Make_Attribute_Reference (Loc,
297 Prefix => Make_Identifier (Loc, Name_uA),
298 Attribute_Name => Name_Range,
299 Expressions => New_List (
300 Make_Integer_Literal (Loc, N))))),
301 Statements => Test_One_Dimension (N + 1)),
302 Make_Simple_Return_Statement (Loc,
303 Expression => New_Occurrence_Of (Standard_True, Loc)));
305 end Test_One_Dimension;
307 -- Start of processing for Build_Array_VS_Func
310 Index_List := New_List;
311 Body_Stmts := Test_One_Dimension (1);
313 -- Parameter is always (A : A_Typ)
315 Formals := New_List (
316 Make_Parameter_Specification (Loc,
317 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uA),
319 Out_Present => False,
320 Parameter_Type => New_Occurrence_Of (A_Type, Loc)));
324 Set_Ekind (Func_Id, E_Function);
325 Set_Is_Internal (Func_Id);
328 Make_Subprogram_Body (Loc,
330 Make_Function_Specification (Loc,
331 Defining_Unit_Name => Func_Id,
332 Parameter_Specifications => Formals,
334 New_Occurrence_Of (Standard_Boolean, Loc)),
335 Declarations => New_List,
336 Handled_Statement_Sequence =>
337 Make_Handled_Sequence_Of_Statements (Loc,
338 Statements => Body_Stmts)));
340 if not Debug_Generated_Code then
341 Set_Debug_Info_Off (Func_Id);
344 Set_Is_Pure (Func_Id);
346 end Build_Array_VS_Func;
348 --------------------------
349 -- Build_Record_VS_Func --
350 --------------------------
354 -- function _Valid_Scalars (X : T) return Boolean is
356 -- -- Check discriminants
358 -- if not X.D1'Valid_Scalars or else
359 -- not X.D2'Valid_Scalars or else
365 -- -- Check components
367 -- if not X.C1'Valid_Scalars or else
368 -- not X.C2'Valid_Scalars or else
374 -- -- Check variant part
378 -- if not X.C2'Valid_Scalars or else
379 -- not X.C3'Valid_Scalars or else
386 -- if not X.Cn'Valid_Scalars or else
394 -- end _Valid_Scalars;
396 function Build_Record_VS_Func
398 Nod : Node_Id) return Entity_Id
400 Loc : constant Source_Ptr := Sloc (R_Type);
401 Func_Id : constant Entity_Id := Make_Temporary (Loc, 'V');
402 X : constant Entity_Id := Make_Defining_Identifier (Loc, Name_X);
404 function Make_VS_Case
407 Discrs : Elist_Id := New_Elmt_List) return List_Id;
408 -- Building block for variant valid scalars. Given a Component_List node
409 -- CL, it generates an 'if' followed by a 'case' statement that compares
410 -- all components of local temporaries named X and Y (that are declared
411 -- as formals at some upper level). E provides the Sloc to be used for
412 -- the generated code.
416 L : List_Id) return Node_Id;
417 -- Building block for variant validate scalars. Given the list, L, of
418 -- components (or discriminants) L, it generates a return statement that
419 -- compares all components of local temporaries named X and Y (that are
420 -- declared as formals at some upper level). E provides the Sloc to be
421 -- used for the generated code.
427 -- <Make_VS_If on shared components>
430 -- when V1 => <Make_VS_Case> on subcomponents
432 -- when Vn => <Make_VS_Case> on subcomponents
435 function Make_VS_Case
438 Discrs : Elist_Id := New_Elmt_List) return List_Id
440 Loc : constant Source_Ptr := Sloc (E);
441 Result : constant List_Id := New_List;
446 Append_To (Result, Make_VS_If (E, Component_Items (CL)));
448 if No (Variant_Part (CL)) then
452 Variant := First_Non_Pragma (Variants (Variant_Part (CL)));
458 Alt_List := New_List;
459 while Present (Variant) loop
461 Make_Case_Statement_Alternative (Loc,
462 Discrete_Choices => New_Copy_List (Discrete_Choices (Variant)),
464 Make_VS_Case (E, Component_List (Variant), Discrs)));
465 Next_Non_Pragma (Variant);
469 Make_Case_Statement (Loc,
471 Make_Selected_Component (Loc,
472 Prefix => Make_Identifier (Loc, Name_X),
473 Selector_Name => New_Copy (Name (Variant_Part (CL)))),
474 Alternatives => Alt_List));
486 -- not X.C1'Valid_Scalars
488 -- not X.C2'Valid_Scalars
494 -- or a null statement if the list L is empty
498 L : List_Id) return Node_Id
500 Loc : constant Source_Ptr := Sloc (E);
503 Field_Name : Name_Id;
508 return Make_Null_Statement (Loc);
513 C := First_Non_Pragma (L);
514 while Present (C) loop
515 Def_Id := Defining_Identifier (C);
516 Field_Name := Chars (Def_Id);
518 -- The tags need not be checked since they will always be valid
520 -- Note also that in the following, we use Make_Identifier for
521 -- the component names. Use of New_Occurrence_Of to identify
522 -- the components would be incorrect because wrong entities for
523 -- discriminants could be picked up in the private type case.
525 -- Don't bother with abstract parent in interface case
527 if Field_Name = Name_uParent
528 and then Is_Interface (Etype (Def_Id))
532 -- Don't bother with tag, always valid, and not scalar anyway
534 elsif Field_Name = Name_uTag then
537 -- Don't bother with component with no scalar components
539 elsif not Scalar_Part_Present (Etype (Def_Id)) then
542 -- Normal case, generate Valid_Scalars attribute reference
545 Evolve_Or_Else (Cond,
548 Make_Attribute_Reference (Loc,
550 Make_Selected_Component (Loc,
552 Make_Identifier (Loc, Name_X),
554 Make_Identifier (Loc, Field_Name)),
555 Attribute_Name => Name_Valid_Scalars)));
562 return Make_Null_Statement (Loc);
566 Make_Implicit_If_Statement (E,
568 Then_Statements => New_List (
569 Make_Simple_Return_Statement (Loc,
571 New_Occurrence_Of (Standard_False, Loc))));
576 -- Local Declarations
578 Def : constant Node_Id := Parent (R_Type);
579 Comps : constant Node_Id := Component_List (Type_Definition (Def));
580 Stmts : constant List_Id := New_List;
581 Pspecs : constant List_Id := New_List;
585 Make_Parameter_Specification (Loc,
586 Defining_Identifier => X,
587 Parameter_Type => New_Occurrence_Of (R_Type, Loc)));
590 Make_VS_If (R_Type, Discriminant_Specifications (Def)));
591 Append_List_To (Stmts, Make_VS_Case (R_Type, Comps));
594 Make_Simple_Return_Statement (Loc,
595 Expression => New_Occurrence_Of (Standard_True, Loc)));
598 Make_Subprogram_Body (Loc,
600 Make_Function_Specification (Loc,
601 Defining_Unit_Name => Func_Id,
602 Parameter_Specifications => Pspecs,
603 Result_Definition => New_Occurrence_Of (Standard_Boolean, Loc)),
604 Declarations => New_List,
605 Handled_Statement_Sequence =>
606 Make_Handled_Sequence_Of_Statements (Loc, Statements => Stmts)),
607 Suppress => Discriminant_Check);
609 if not Debug_Generated_Code then
610 Set_Debug_Info_Off (Func_Id);
613 Set_Is_Pure (Func_Id);
615 end Build_Record_VS_Func;
617 ----------------------------------
618 -- Compile_Stream_Body_In_Scope --
619 ----------------------------------
621 procedure Compile_Stream_Body_In_Scope
627 Installed : Boolean := False;
628 Scop : constant Entity_Id := Scope (Arr);
629 Curr : constant Entity_Id := Current_Scope;
633 and then not In_Open_Scopes (Scop)
634 and then Ekind (Scop) = E_Package
636 -- If we are within an instance body, then all visibility has been
637 -- established already and there is no need to install the package.
639 and then not In_Instance_Body
642 Install_Visible_Declarations (Scop);
643 Install_Private_Declarations (Scop);
646 -- The entities in the package are now visible, but the generated
647 -- stream entity must appear in the current scope (usually an
648 -- enclosing stream function) so that itypes all have their proper
655 Insert_Action (N, Decl);
657 Insert_Action (N, Decl, Suppress => All_Checks);
662 -- Remove extra copy of current scope, and package itself
665 End_Package_Scope (Scop);
667 end Compile_Stream_Body_In_Scope;
669 -----------------------------------
670 -- Expand_Access_To_Protected_Op --
671 -----------------------------------
673 procedure Expand_Access_To_Protected_Op
678 -- The value of the attribute_reference is a record containing two
679 -- fields: an access to the protected object, and an access to the
680 -- subprogram itself. The prefix is a selected component.
682 Loc : constant Source_Ptr := Sloc (N);
684 Btyp : constant Entity_Id := Base_Type (Typ);
687 E_T : constant Entity_Id := Equivalent_Type (Btyp);
688 Acc : constant Entity_Id :=
689 Etype (Next_Component (First_Component (E_T)));
693 -- Start of processing for Expand_Access_To_Protected_Op
696 -- Within the body of the protected type, the prefix designates a local
697 -- operation, and the object is the first parameter of the corresponding
698 -- protected body of the current enclosing operation.
700 if Is_Entity_Name (Pref) then
701 -- All indirect calls are external calls, so must do locking and
702 -- barrier reevaluation, even if the 'Access occurs within the
703 -- protected body. Hence the call to External_Subprogram, as opposed
704 -- to Protected_Body_Subprogram, below. See RM-9.5(5). This means
705 -- that indirect calls from within the same protected body will
706 -- deadlock, as allowed by RM-9.5.1(8,15,17).
708 Sub := New_Occurrence_Of (External_Subprogram (Entity (Pref)), Loc);
710 -- Don't traverse the scopes when the attribute occurs within an init
711 -- proc, because we directly use the _init formal of the init proc in
714 Curr := Current_Scope;
715 if not Is_Init_Proc (Curr) then
716 pragma Assert (In_Open_Scopes (Scope (Entity (Pref))));
718 while Scope (Curr) /= Scope (Entity (Pref)) loop
719 Curr := Scope (Curr);
723 -- In case of protected entries the first formal of its Protected_
724 -- Body_Subprogram is the address of the object.
726 if Ekind (Curr) = E_Entry then
730 (Protected_Body_Subprogram (Curr)), Loc);
732 -- If the current scope is an init proc, then use the address of the
733 -- _init formal as the object reference.
735 elsif Is_Init_Proc (Curr) then
737 Make_Attribute_Reference (Loc,
738 Prefix => New_Occurrence_Of (First_Formal (Curr), Loc),
739 Attribute_Name => Name_Address);
741 -- In case of protected subprograms the first formal of its
742 -- Protected_Body_Subprogram is the object and we get its address.
746 Make_Attribute_Reference (Loc,
750 (Protected_Body_Subprogram (Curr)), Loc),
751 Attribute_Name => Name_Address);
754 -- Case where the prefix is not an entity name. Find the
755 -- version of the protected operation to be called from
756 -- outside the protected object.
762 (Entity (Selector_Name (Pref))), Loc);
765 Make_Attribute_Reference (Loc,
766 Prefix => Relocate_Node (Prefix (Pref)),
767 Attribute_Name => Name_Address);
771 Make_Attribute_Reference (Loc,
773 Attribute_Name => Name_Access);
775 -- We set the type of the access reference to the already generated
776 -- access_to_subprogram type, and declare the reference analyzed, to
777 -- prevent further expansion when the enclosing aggregate is analyzed.
779 Set_Etype (Sub_Ref, Acc);
780 Set_Analyzed (Sub_Ref);
784 Expressions => New_List (Obj_Ref, Sub_Ref));
786 -- Sub_Ref has been marked as analyzed, but we still need to make sure
787 -- Sub is correctly frozen.
789 Freeze_Before (N, Entity (Sub));
792 Analyze_And_Resolve (N, E_T);
794 -- For subsequent analysis, the node must retain its type. The backend
795 -- will replace it with the equivalent type where needed.
798 end Expand_Access_To_Protected_Op;
800 --------------------------
801 -- Expand_Fpt_Attribute --
802 --------------------------
804 procedure Expand_Fpt_Attribute
810 Loc : constant Source_Ptr := Sloc (N);
811 Typ : constant Entity_Id := Etype (N);
815 -- The function name is the selected component Attr_xxx.yyy where
816 -- Attr_xxx is the package name, and yyy is the argument Nam.
818 -- Note: it would be more usual to have separate RE entries for each
819 -- of the entities in the Fat packages, but first they have identical
820 -- names (so we would have to have lots of renaming declarations to
821 -- meet the normal RE rule of separate names for all runtime entities),
822 -- and second there would be an awful lot of them.
825 Make_Selected_Component (Loc,
826 Prefix => New_Occurrence_Of (RTE (Pkg), Loc),
827 Selector_Name => Make_Identifier (Loc, Nam));
829 -- The generated call is given the provided set of parameters, and then
830 -- wrapped in a conversion which converts the result to the target type
831 -- We use the base type as the target because a range check may be
835 Unchecked_Convert_To (Base_Type (Etype (N)),
836 Make_Function_Call (Loc,
838 Parameter_Associations => Args)));
840 Analyze_And_Resolve (N, Typ);
841 end Expand_Fpt_Attribute;
843 ----------------------------
844 -- Expand_Fpt_Attribute_R --
845 ----------------------------
847 -- The single argument is converted to its root type to call the
848 -- appropriate runtime function, with the actual call being built
849 -- by Expand_Fpt_Attribute
851 procedure Expand_Fpt_Attribute_R (N : Node_Id) is
852 E1 : constant Node_Id := First (Expressions (N));
856 Find_Fat_Info (Etype (E1), Ftp, Pkg);
858 (N, Pkg, Attribute_Name (N),
859 New_List (Unchecked_Convert_To (Ftp, Relocate_Node (E1))));
860 end Expand_Fpt_Attribute_R;
862 -----------------------------
863 -- Expand_Fpt_Attribute_RI --
864 -----------------------------
866 -- The first argument is converted to its root type and the second
867 -- argument is converted to standard long long integer to call the
868 -- appropriate runtime function, with the actual call being built
869 -- by Expand_Fpt_Attribute
871 procedure Expand_Fpt_Attribute_RI (N : Node_Id) is
872 E1 : constant Node_Id := First (Expressions (N));
875 E2 : constant Node_Id := Next (E1);
877 Find_Fat_Info (Etype (E1), Ftp, Pkg);
879 (N, Pkg, Attribute_Name (N),
881 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
882 Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2))));
883 end Expand_Fpt_Attribute_RI;
885 -----------------------------
886 -- Expand_Fpt_Attribute_RR --
887 -----------------------------
889 -- The two arguments are converted to their root types to call the
890 -- appropriate runtime function, with the actual call being built
891 -- by Expand_Fpt_Attribute
893 procedure Expand_Fpt_Attribute_RR (N : Node_Id) is
894 E1 : constant Node_Id := First (Expressions (N));
895 E2 : constant Node_Id := Next (E1);
900 Find_Fat_Info (Etype (E1), Ftp, Pkg);
902 (N, Pkg, Attribute_Name (N),
904 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
905 Unchecked_Convert_To (Ftp, Relocate_Node (E2))));
906 end Expand_Fpt_Attribute_RR;
908 ---------------------------------
909 -- Expand_Loop_Entry_Attribute --
910 ---------------------------------
912 procedure Expand_Loop_Entry_Attribute (N : Node_Id) is
913 procedure Build_Conditional_Block
917 If_Stmt : out Node_Id;
918 Blk_Stmt : out Node_Id);
919 -- Create a block Blk_Stmt with an empty declarative list and a single
920 -- loop Loop_Stmt. The block is encased in an if statement If_Stmt with
921 -- condition Cond. If_Stmt is Empty when there is no condition provided.
923 function Is_Array_Iteration (N : Node_Id) return Boolean;
924 -- Determine whether loop statement N denotes an Ada 2012 iteration over
927 -----------------------------
928 -- Build_Conditional_Block --
929 -----------------------------
931 procedure Build_Conditional_Block
935 If_Stmt : out Node_Id;
936 Blk_Stmt : out Node_Id)
939 -- Do not reanalyze the original loop statement because it is simply
942 Set_Analyzed (Loop_Stmt);
945 Make_Block_Statement (Loc,
946 Declarations => New_List,
947 Handled_Statement_Sequence =>
948 Make_Handled_Sequence_Of_Statements (Loc,
949 Statements => New_List (Loop_Stmt)));
951 if Present (Cond) then
953 Make_If_Statement (Loc,
955 Then_Statements => New_List (Blk_Stmt));
959 end Build_Conditional_Block;
961 ------------------------
962 -- Is_Array_Iteration --
963 ------------------------
965 function Is_Array_Iteration (N : Node_Id) return Boolean is
966 Stmt : constant Node_Id := Original_Node (N);
970 if Nkind (Stmt) = N_Loop_Statement
971 and then Present (Iteration_Scheme (Stmt))
972 and then Present (Iterator_Specification (Iteration_Scheme (Stmt)))
974 Iter := Iterator_Specification (Iteration_Scheme (Stmt));
977 Of_Present (Iter) and then Is_Array_Type (Etype (Name (Iter)));
981 end Is_Array_Iteration;
985 Exprs : constant List_Id := Expressions (N);
986 Pref : constant Node_Id := Prefix (N);
987 Typ : constant Entity_Id := Etype (Pref);
1000 Temp_Id : Entity_Id;
1002 -- Start of processing for Expand_Loop_Entry_Attribute
1005 -- Step 1: Find the related loop
1007 -- The loop label variant of attribute 'Loop_Entry already has all the
1008 -- information in its expression.
1010 if Present (Exprs) then
1011 Loop_Id := Entity (First (Exprs));
1012 Loop_Stmt := Label_Construct (Parent (Loop_Id));
1014 -- Climb the parent chain to find the nearest enclosing loop. Skip all
1015 -- internally generated loops for quantified expressions and for
1016 -- element iterators over multidimensional arrays: pragma applies to
1021 while Present (Loop_Stmt) loop
1022 if Nkind (Loop_Stmt) = N_Loop_Statement
1023 and then Comes_From_Source (Loop_Stmt)
1028 Loop_Stmt := Parent (Loop_Stmt);
1031 Loop_Id := Entity (Identifier (Loop_Stmt));
1034 Loc := Sloc (Loop_Stmt);
1036 -- Step 2: Transform the loop
1038 -- The loop has already been transformed during the expansion of a prior
1039 -- 'Loop_Entry attribute. Retrieve the declarative list of the block.
1041 if Has_Loop_Entry_Attributes (Loop_Id) then
1043 -- When the related loop name appears as the argument of attribute
1044 -- Loop_Entry, the corresponding label construct is the generated
1045 -- block statement. This is because the expander reuses the label.
1047 if Nkind (Loop_Stmt) = N_Block_Statement then
1048 Decls := Declarations (Loop_Stmt);
1050 -- In all other cases, the loop must appear in the handled sequence
1051 -- of statements of the generated block.
1055 (Nkind (Parent (Loop_Stmt)) = N_Handled_Sequence_Of_Statements
1057 Nkind (Parent (Parent (Loop_Stmt))) = N_Block_Statement);
1059 Decls := Declarations (Parent (Parent (Loop_Stmt)));
1064 -- Transform the loop into a conditional block
1067 Set_Has_Loop_Entry_Attributes (Loop_Id);
1068 Scheme := Iteration_Scheme (Loop_Stmt);
1070 -- Infinite loops are transformed into:
1073 -- Temp1 : constant <type of Pref1> := <Pref1>;
1075 -- TempN : constant <type of PrefN> := <PrefN>;
1078 -- <original source statements with attribute rewrites>
1083 Build_Conditional_Block (Loc,
1085 Loop_Stmt => Relocate_Node (Loop_Stmt),
1091 -- While loops are transformed into:
1093 -- function Fnn return Boolean is
1095 -- <condition actions>
1096 -- return <condition>;
1101 -- Temp1 : constant <type of Pref1> := <Pref1>;
1103 -- TempN : constant <type of PrefN> := <PrefN>;
1106 -- <original source statements with attribute rewrites>
1107 -- exit when not Fnn;
1112 -- Note that loops over iterators and containers are already
1113 -- converted into while loops.
1115 elsif Present (Condition (Scheme)) then
1117 Func_Decl : Node_Id;
1118 Func_Id : Entity_Id;
1122 -- Wrap the condition of the while loop in a Boolean function.
1123 -- This avoids the duplication of the same code which may lead
1124 -- to gigi issues with respect to multiple declaration of the
1125 -- same entity in the presence of side effects or checks. Note
1126 -- that the condition actions must also be relocated to the
1127 -- wrapping function.
1130 -- <condition actions>
1131 -- return <condition>;
1133 if Present (Condition_Actions (Scheme)) then
1134 Stmts := Condition_Actions (Scheme);
1140 Make_Simple_Return_Statement (Loc,
1141 Expression => Relocate_Node (Condition (Scheme))));
1144 -- function Fnn return Boolean is
1149 Func_Id := Make_Temporary (Loc, 'F');
1151 Make_Subprogram_Body (Loc,
1153 Make_Function_Specification (Loc,
1154 Defining_Unit_Name => Func_Id,
1155 Result_Definition =>
1156 New_Occurrence_Of (Standard_Boolean, Loc)),
1157 Declarations => Empty_List,
1158 Handled_Statement_Sequence =>
1159 Make_Handled_Sequence_Of_Statements (Loc,
1160 Statements => Stmts));
1162 -- The function is inserted before the related loop. Make sure
1163 -- to analyze it in the context of the loop's enclosing scope.
1165 Push_Scope (Scope (Loop_Id));
1166 Insert_Action (Loop_Stmt, Func_Decl);
1169 -- Transform the original while loop into an infinite loop
1170 -- where the last statement checks the negated condition. This
1171 -- placement ensures that the condition will not be evaluated
1172 -- twice on the first iteration.
1174 Set_Iteration_Scheme (Loop_Stmt, Empty);
1178 -- exit when not Fnn;
1180 Append_To (Statements (Loop_Stmt),
1181 Make_Exit_Statement (Loc,
1185 Make_Function_Call (Loc,
1186 Name => New_Occurrence_Of (Func_Id, Loc)))));
1188 Build_Conditional_Block (Loc,
1190 Make_Function_Call (Loc,
1191 Name => New_Occurrence_Of (Func_Id, Loc)),
1192 Loop_Stmt => Relocate_Node (Loop_Stmt),
1197 -- Ada 2012 iteration over an array is transformed into:
1199 -- if <Array_Nam>'Length (1) > 0
1200 -- and then <Array_Nam>'Length (N) > 0
1203 -- Temp1 : constant <type of Pref1> := <Pref1>;
1205 -- TempN : constant <type of PrefN> := <PrefN>;
1207 -- for X in ... loop -- multiple loops depending on dims
1208 -- <original source statements with attribute rewrites>
1213 elsif Is_Array_Iteration (Loop_Stmt) then
1215 Array_Nam : constant Entity_Id :=
1216 Entity (Name (Iterator_Specification
1217 (Iteration_Scheme (Original_Node (Loop_Stmt)))));
1218 Num_Dims : constant Pos :=
1219 Number_Dimensions (Etype (Array_Nam));
1220 Cond : Node_Id := Empty;
1224 -- Generate a check which determines whether all dimensions of
1225 -- the array are non-null.
1227 for Dim in 1 .. Num_Dims loop
1231 Make_Attribute_Reference (Loc,
1232 Prefix => New_Occurrence_Of (Array_Nam, Loc),
1233 Attribute_Name => Name_Length,
1234 Expressions => New_List (
1235 Make_Integer_Literal (Loc, Dim))),
1237 Make_Integer_Literal (Loc, 0));
1245 Right_Opnd => Check);
1249 Build_Conditional_Block (Loc,
1251 Loop_Stmt => Relocate_Node (Loop_Stmt),
1256 -- For loops are transformed into:
1258 -- if <Low> <= <High> then
1260 -- Temp1 : constant <type of Pref1> := <Pref1>;
1262 -- TempN : constant <type of PrefN> := <PrefN>;
1264 -- for <Def_Id> in <Low> .. <High> loop
1265 -- <original source statements with attribute rewrites>
1270 elsif Present (Loop_Parameter_Specification (Scheme)) then
1272 Loop_Spec : constant Node_Id :=
1273 Loop_Parameter_Specification (Scheme);
1278 Subt_Def := Discrete_Subtype_Definition (Loop_Spec);
1280 -- When the loop iterates over a subtype indication with a
1281 -- range, use the low and high bounds of the subtype itself.
1283 if Nkind (Subt_Def) = N_Subtype_Indication then
1284 Subt_Def := Scalar_Range (Etype (Subt_Def));
1287 pragma Assert (Nkind (Subt_Def) = N_Range);
1294 Left_Opnd => New_Copy_Tree (Low_Bound (Subt_Def)),
1295 Right_Opnd => New_Copy_Tree (High_Bound (Subt_Def)));
1297 Build_Conditional_Block (Loc,
1299 Loop_Stmt => Relocate_Node (Loop_Stmt),
1305 Decls := Declarations (Blk);
1308 -- Step 3: Create a constant to capture the value of the prefix at the
1309 -- entry point into the loop.
1311 Temp_Id := Make_Temporary (Loc, 'P');
1313 -- Preserve the tag of the prefix by offering a specific view of the
1314 -- class-wide version of the prefix.
1316 if Is_Tagged_Type (Typ) then
1319 -- CW_Temp : constant Typ'Class := Typ'Class (Pref);
1321 CW_Temp := Make_Temporary (Loc, 'T');
1322 CW_Typ := Class_Wide_Type (Typ);
1325 Make_Object_Declaration (Loc,
1326 Defining_Identifier => CW_Temp,
1327 Constant_Present => True,
1328 Object_Definition => New_Occurrence_Of (CW_Typ, Loc),
1330 Convert_To (CW_Typ, Relocate_Node (Pref)));
1331 Append_To (Decls, CW_Decl);
1334 -- Temp : Typ renames Typ (CW_Temp);
1337 Make_Object_Renaming_Declaration (Loc,
1338 Defining_Identifier => Temp_Id,
1339 Subtype_Mark => New_Occurrence_Of (Typ, Loc),
1341 Convert_To (Typ, New_Occurrence_Of (CW_Temp, Loc)));
1342 Append_To (Decls, Temp_Decl);
1350 -- Temp : constant Typ := Pref;
1353 Make_Object_Declaration (Loc,
1354 Defining_Identifier => Temp_Id,
1355 Constant_Present => True,
1356 Object_Definition => New_Occurrence_Of (Typ, Loc),
1357 Expression => Relocate_Node (Pref));
1358 Append_To (Decls, Temp_Decl);
1361 -- Step 4: Analyze all bits
1363 Installed := Current_Scope = Scope (Loop_Id);
1365 -- Depending on the pracement of attribute 'Loop_Entry relative to the
1366 -- associated loop, ensure the proper visibility for analysis.
1368 if not Installed then
1369 Push_Scope (Scope (Loop_Id));
1372 -- The analysis of the conditional block takes care of the constant
1375 if Present (Result) then
1376 Rewrite (Loop_Stmt, Result);
1377 Analyze (Loop_Stmt);
1379 -- The conditional block was analyzed when a previous 'Loop_Entry was
1380 -- expanded. There is no point in reanalyzing the block, simply analyze
1381 -- the declaration of the constant.
1384 if Present (CW_Decl) then
1388 Analyze (Temp_Decl);
1391 Rewrite (N, New_Occurrence_Of (Temp_Id, Loc));
1394 if not Installed then
1397 end Expand_Loop_Entry_Attribute;
1399 ------------------------------
1400 -- Expand_Min_Max_Attribute --
1401 ------------------------------
1403 procedure Expand_Min_Max_Attribute (N : Node_Id) is
1405 -- Min and Max are handled by the back end (except that static cases
1406 -- have already been evaluated during semantic processing, although the
1407 -- back end should not count on this). The one bit of special processing
1408 -- required in the normal case is that these two attributes typically
1409 -- generate conditionals in the code, so check the relevant restriction.
1411 Check_Restriction (No_Implicit_Conditionals, N);
1413 -- In Modify_Tree_For_C mode, we rewrite as an if expression
1415 if Modify_Tree_For_C then
1417 Loc : constant Source_Ptr := Sloc (N);
1418 Typ : constant Entity_Id := Etype (N);
1419 Expr : constant Node_Id := First (Expressions (N));
1420 Left : constant Node_Id := Relocate_Node (Expr);
1421 Right : constant Node_Id := Relocate_Node (Next (Expr));
1423 function Make_Compare (Left, Right : Node_Id) return Node_Id;
1424 -- Returns Left >= Right for Max, Left <= Right for Min
1430 function Make_Compare (Left, Right : Node_Id) return Node_Id is
1432 if Attribute_Name (N) = Name_Max then
1436 Right_Opnd => Right);
1441 Right_Opnd => Right);
1445 -- Start of processing for Min_Max
1448 -- If both Left and Right are side effect free, then we can just
1449 -- use Duplicate_Expr to duplicate the references and return
1451 -- (if Left >=|<= Right then Left else Right)
1453 if Side_Effect_Free (Left) and then Side_Effect_Free (Right) then
1455 Make_If_Expression (Loc,
1456 Expressions => New_List (
1457 Make_Compare (Left, Right),
1458 Duplicate_Subexpr_No_Checks (Left),
1459 Duplicate_Subexpr_No_Checks (Right))));
1461 -- Otherwise we generate declarations to capture the values. We
1462 -- can't put these declarations inside the if expression, since
1463 -- we could end up with an N_Expression_With_Actions which has
1464 -- declarations in the actions, forbidden for Modify_Tree_For_C.
1466 -- The translation is
1468 -- T1 : styp; -- inserted high up in tree
1469 -- T2 : styp; -- inserted high up in tree
1472 -- T1 := styp!(Left);
1473 -- T2 := styp!(Right);
1475 -- (if T1 >=|<= T2 then typ!(T1) else typ!(T2))
1478 -- We insert the T1,T2 declarations with Insert_Declaration which
1479 -- inserts these declarations high up in the tree unconditionally.
1480 -- This is safe since no code is associated with the declarations.
1481 -- Here styp is a standard type whose Esize matches the size of
1482 -- our type. We do this because the actual type may be a result of
1483 -- some local declaration which would not be visible at the point
1484 -- where we insert the declarations of T1 and T2.
1488 T1 : constant Entity_Id := Make_Temporary (Loc, 'T', Left);
1489 T2 : constant Entity_Id := Make_Temporary (Loc, 'T', Left);
1490 Styp : constant Entity_Id := Matching_Standard_Type (Typ);
1493 Insert_Declaration (N,
1494 Make_Object_Declaration (Loc,
1495 Defining_Identifier => T1,
1496 Object_Definition => New_Occurrence_Of (Styp, Loc)));
1498 Insert_Declaration (N,
1499 Make_Object_Declaration (Loc,
1500 Defining_Identifier => T2,
1501 Object_Definition => New_Occurrence_Of (Styp, Loc)));
1504 Make_Expression_With_Actions (Loc,
1505 Actions => New_List (
1506 Make_Assignment_Statement (Loc,
1507 Name => New_Occurrence_Of (T1, Loc),
1508 Expression => Unchecked_Convert_To (Styp, Left)),
1509 Make_Assignment_Statement (Loc,
1510 Name => New_Occurrence_Of (T2, Loc),
1511 Expression => Unchecked_Convert_To (Styp, Right))),
1514 Make_If_Expression (Loc,
1515 Expressions => New_List (
1517 (New_Occurrence_Of (T1, Loc),
1518 New_Occurrence_Of (T2, Loc)),
1519 Unchecked_Convert_To (Typ,
1520 New_Occurrence_Of (T1, Loc)),
1521 Unchecked_Convert_To (Typ,
1522 New_Occurrence_Of (T2, Loc))))));
1526 Analyze_And_Resolve (N, Typ);
1529 end Expand_Min_Max_Attribute;
1531 ----------------------------------
1532 -- Expand_N_Attribute_Reference --
1533 ----------------------------------
1535 procedure Expand_N_Attribute_Reference (N : Node_Id) is
1536 Loc : constant Source_Ptr := Sloc (N);
1537 Typ : constant Entity_Id := Etype (N);
1538 Btyp : constant Entity_Id := Base_Type (Typ);
1539 Pref : constant Node_Id := Prefix (N);
1540 Ptyp : constant Entity_Id := Etype (Pref);
1541 Exprs : constant List_Id := Expressions (N);
1542 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
1544 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id);
1545 -- Rewrites a stream attribute for Read, Write or Output with the
1546 -- procedure call. Pname is the entity for the procedure to call.
1548 ------------------------------
1549 -- Rewrite_Stream_Proc_Call --
1550 ------------------------------
1552 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id) is
1553 Item : constant Node_Id := Next (First (Exprs));
1554 Formal : constant Entity_Id := Next_Formal (First_Formal (Pname));
1555 Formal_Typ : constant Entity_Id := Etype (Formal);
1556 Is_Written : constant Boolean := (Ekind (Formal) /= E_In_Parameter);
1559 -- The expansion depends on Item, the second actual, which is
1560 -- the object being streamed in or out.
1562 -- If the item is a component of a packed array type, and
1563 -- a conversion is needed on exit, we introduce a temporary to
1564 -- hold the value, because otherwise the packed reference will
1565 -- not be properly expanded.
1567 if Nkind (Item) = N_Indexed_Component
1568 and then Is_Packed (Base_Type (Etype (Prefix (Item))))
1569 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
1573 Temp : constant Entity_Id := Make_Temporary (Loc, 'V');
1579 Make_Object_Declaration (Loc,
1580 Defining_Identifier => Temp,
1581 Object_Definition =>
1582 New_Occurrence_Of (Formal_Typ, Loc));
1583 Set_Etype (Temp, Formal_Typ);
1586 Make_Assignment_Statement (Loc,
1587 Name => New_Copy_Tree (Item),
1589 Unchecked_Convert_To
1590 (Etype (Item), New_Occurrence_Of (Temp, Loc)));
1592 Rewrite (Item, New_Occurrence_Of (Temp, Loc));
1596 Make_Procedure_Call_Statement (Loc,
1597 Name => New_Occurrence_Of (Pname, Loc),
1598 Parameter_Associations => Exprs),
1601 Rewrite (N, Make_Null_Statement (Loc));
1606 -- For the class-wide dispatching cases, and for cases in which
1607 -- the base type of the second argument matches the base type of
1608 -- the corresponding formal parameter (that is to say the stream
1609 -- operation is not inherited), we are all set, and can use the
1610 -- argument unchanged.
1612 -- For all other cases we do an unchecked conversion of the second
1613 -- parameter to the type of the formal of the procedure we are
1614 -- calling. This deals with the private type cases, and with going
1615 -- to the root type as required in elementary type case.
1617 if not Is_Class_Wide_Type (Entity (Pref))
1618 and then not Is_Class_Wide_Type (Etype (Item))
1619 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
1622 Unchecked_Convert_To (Formal_Typ, Relocate_Node (Item)));
1624 -- For untagged derived types set Assignment_OK, to prevent
1625 -- copies from being created when the unchecked conversion
1626 -- is expanded (which would happen in Remove_Side_Effects
1627 -- if Expand_N_Unchecked_Conversion were allowed to call
1628 -- Force_Evaluation). The copy could violate Ada semantics in
1629 -- cases such as an actual that is an out parameter. Note that
1630 -- this approach is also used in exp_ch7 for calls to controlled
1631 -- type operations to prevent problems with actuals wrapped in
1632 -- unchecked conversions.
1634 if Is_Untagged_Derivation (Etype (Expression (Item))) then
1635 Set_Assignment_OK (Item);
1639 -- The stream operation to call may be a renaming created by an
1640 -- attribute definition clause, and may not be frozen yet. Ensure
1641 -- that it has the necessary extra formals.
1643 if not Is_Frozen (Pname) then
1644 Create_Extra_Formals (Pname);
1647 -- And now rewrite the call
1650 Make_Procedure_Call_Statement (Loc,
1651 Name => New_Occurrence_Of (Pname, Loc),
1652 Parameter_Associations => Exprs));
1655 end Rewrite_Stream_Proc_Call;
1657 -- Start of processing for Expand_N_Attribute_Reference
1660 -- Do required validity checking, if enabled. Do not apply check to
1661 -- output parameters of an Asm instruction, since the value of this
1662 -- is not set till after the attribute has been elaborated, and do
1663 -- not apply the check to the arguments of a 'Read or 'Input attribute
1664 -- reference since the scalar argument is an OUT scalar.
1666 if Validity_Checks_On and then Validity_Check_Operands
1667 and then Id /= Attribute_Asm_Output
1668 and then Id /= Attribute_Read
1669 and then Id /= Attribute_Input
1674 Expr := First (Expressions (N));
1675 while Present (Expr) loop
1676 Ensure_Valid (Expr);
1682 -- Ada 2005 (AI-318-02): If attribute prefix is a call to a build-in-
1683 -- place function, then a temporary return object needs to be created
1684 -- and access to it must be passed to the function. Currently we limit
1685 -- such functions to those with inherently limited result subtypes, but
1686 -- eventually we plan to expand the functions that are treated as
1687 -- build-in-place to include other composite result types.
1689 if Ada_Version >= Ada_2005
1690 and then Is_Build_In_Place_Function_Call (Pref)
1692 Make_Build_In_Place_Call_In_Anonymous_Context (Pref);
1695 -- If prefix is a protected type name, this is a reference to the
1696 -- current instance of the type. For a component definition, nothing
1697 -- to do (expansion will occur in the init proc). In other contexts,
1698 -- rewrite into reference to current instance.
1700 if Is_Protected_Self_Reference (Pref)
1702 (Nkind_In (Parent (N), N_Index_Or_Discriminant_Constraint,
1703 N_Discriminant_Association)
1704 and then Nkind (Parent (Parent (Parent (Parent (N))))) =
1705 N_Component_Definition)
1707 -- No action needed for these attributes since the current instance
1708 -- will be rewritten to be the name of the _object parameter
1709 -- associated with the enclosing protected subprogram (see below).
1711 and then Id /= Attribute_Access
1712 and then Id /= Attribute_Unchecked_Access
1713 and then Id /= Attribute_Unrestricted_Access
1715 Rewrite (Pref, Concurrent_Ref (Pref));
1719 -- Remaining processing depends on specific attribute
1721 -- Note: individual sections of the following case statement are
1722 -- allowed to assume there is no code after the case statement, and
1723 -- are legitimately allowed to execute return statements if they have
1724 -- nothing more to do.
1728 -- Attributes related to Ada 2012 iterators
1730 when Attribute_Constant_Indexing |
1731 Attribute_Default_Iterator |
1732 Attribute_Implicit_Dereference |
1733 Attribute_Iterable |
1734 Attribute_Iterator_Element |
1735 Attribute_Variable_Indexing =>
1738 -- Internal attributes used to deal with Ada 2012 delayed aspects. These
1739 -- were already rejected by the parser. Thus they shouldn't appear here.
1741 when Internal_Attribute_Id =>
1742 raise Program_Error;
1748 when Attribute_Access |
1749 Attribute_Unchecked_Access |
1750 Attribute_Unrestricted_Access =>
1752 Access_Cases : declare
1753 Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
1754 Btyp_DDT : Entity_Id;
1756 function Enclosing_Object (N : Node_Id) return Node_Id;
1757 -- If N denotes a compound name (selected component, indexed
1758 -- component, or slice), returns the name of the outermost such
1759 -- enclosing object. Otherwise returns N. If the object is a
1760 -- renaming, then the renamed object is returned.
1762 ----------------------
1763 -- Enclosing_Object --
1764 ----------------------
1766 function Enclosing_Object (N : Node_Id) return Node_Id is
1771 while Nkind_In (Obj_Name, N_Selected_Component,
1772 N_Indexed_Component,
1775 Obj_Name := Prefix (Obj_Name);
1778 return Get_Referenced_Object (Obj_Name);
1779 end Enclosing_Object;
1781 -- Local declarations
1783 Enc_Object : constant Node_Id := Enclosing_Object (Ref_Object);
1785 -- Start of processing for Access_Cases
1788 Btyp_DDT := Designated_Type (Btyp);
1790 -- Handle designated types that come from the limited view
1792 if From_Limited_With (Btyp_DDT)
1793 and then Has_Non_Limited_View (Btyp_DDT)
1795 Btyp_DDT := Non_Limited_View (Btyp_DDT);
1798 -- In order to improve the text of error messages, the designated
1799 -- type of access-to-subprogram itypes is set by the semantics as
1800 -- the associated subprogram entity (see sem_attr). Now we replace
1801 -- such node with the proper E_Subprogram_Type itype.
1803 if Id = Attribute_Unrestricted_Access
1804 and then Is_Subprogram (Directly_Designated_Type (Typ))
1806 -- The following conditions ensure that this special management
1807 -- is done only for "Address!(Prim'Unrestricted_Access)" nodes.
1808 -- At this stage other cases in which the designated type is
1809 -- still a subprogram (instead of an E_Subprogram_Type) are
1810 -- wrong because the semantics must have overridden the type of
1811 -- the node with the type imposed by the context.
1813 if Nkind (Parent (N)) = N_Unchecked_Type_Conversion
1814 and then Etype (Parent (N)) = RTE (RE_Prim_Ptr)
1816 Set_Etype (N, RTE (RE_Prim_Ptr));
1820 Subp : constant Entity_Id :=
1821 Directly_Designated_Type (Typ);
1823 Extra : Entity_Id := Empty;
1824 New_Formal : Entity_Id;
1825 Old_Formal : Entity_Id := First_Formal (Subp);
1826 Subp_Typ : Entity_Id;
1829 Subp_Typ := Create_Itype (E_Subprogram_Type, N);
1830 Set_Etype (Subp_Typ, Etype (Subp));
1831 Set_Returns_By_Ref (Subp_Typ, Returns_By_Ref (Subp));
1833 if Present (Old_Formal) then
1834 New_Formal := New_Copy (Old_Formal);
1835 Set_First_Entity (Subp_Typ, New_Formal);
1838 Set_Scope (New_Formal, Subp_Typ);
1839 Etyp := Etype (New_Formal);
1841 -- Handle itypes. There is no need to duplicate
1842 -- here the itypes associated with record types
1843 -- (i.e the implicit full view of private types).
1846 and then Ekind (Base_Type (Etyp)) /= E_Record_Type
1848 Extra := New_Copy (Etyp);
1849 Set_Parent (Extra, New_Formal);
1850 Set_Etype (New_Formal, Extra);
1851 Set_Scope (Extra, Subp_Typ);
1854 Extra := New_Formal;
1855 Next_Formal (Old_Formal);
1856 exit when No (Old_Formal);
1858 Set_Next_Entity (New_Formal,
1859 New_Copy (Old_Formal));
1860 Next_Entity (New_Formal);
1863 Set_Next_Entity (New_Formal, Empty);
1864 Set_Last_Entity (Subp_Typ, Extra);
1867 -- Now that the explicit formals have been duplicated,
1868 -- any extra formals needed by the subprogram must be
1871 if Present (Extra) then
1872 Set_Extra_Formal (Extra, Empty);
1875 Create_Extra_Formals (Subp_Typ);
1876 Set_Directly_Designated_Type (Typ, Subp_Typ);
1881 if Is_Access_Protected_Subprogram_Type (Btyp) then
1882 Expand_Access_To_Protected_Op (N, Pref, Typ);
1884 -- If prefix is a type name, this is a reference to the current
1885 -- instance of the type, within its initialization procedure.
1887 elsif Is_Entity_Name (Pref)
1888 and then Is_Type (Entity (Pref))
1895 -- If the current instance name denotes a task type, then
1896 -- the access attribute is rewritten to be the name of the
1897 -- "_task" parameter associated with the task type's task
1898 -- procedure. An unchecked conversion is applied to ensure
1899 -- a type match in cases of expander-generated calls (e.g.
1902 if Is_Task_Type (Entity (Pref)) then
1904 First_Entity (Get_Task_Body_Procedure (Entity (Pref)));
1905 while Present (Formal) loop
1906 exit when Chars (Formal) = Name_uTask;
1907 Next_Entity (Formal);
1910 pragma Assert (Present (Formal));
1913 Unchecked_Convert_To (Typ,
1914 New_Occurrence_Of (Formal, Loc)));
1917 elsif Is_Protected_Type (Entity (Pref)) then
1919 -- No action needed for current instance located in a
1920 -- component definition (expansion will occur in the
1923 if Is_Protected_Type (Current_Scope) then
1926 -- If the current instance reference is located in a
1927 -- protected subprogram or entry then rewrite the access
1928 -- attribute to be the name of the "_object" parameter.
1929 -- An unchecked conversion is applied to ensure a type
1930 -- match in cases of expander-generated calls (e.g. init
1933 -- The code may be nested in a block, so find enclosing
1934 -- scope that is a protected operation.
1941 Subp := Current_Scope;
1942 while Ekind_In (Subp, E_Loop, E_Block) loop
1943 Subp := Scope (Subp);
1948 (Protected_Body_Subprogram (Subp));
1950 -- For a protected subprogram the _Object parameter
1951 -- is the protected record, so we create an access
1952 -- to it. The _Object parameter of an entry is an
1955 if Ekind (Subp) = E_Entry then
1957 Unchecked_Convert_To (Typ,
1958 New_Occurrence_Of (Formal, Loc)));
1963 Unchecked_Convert_To (Typ,
1964 Make_Attribute_Reference (Loc,
1965 Attribute_Name => Name_Unrestricted_Access,
1967 New_Occurrence_Of (Formal, Loc))));
1968 Analyze_And_Resolve (N);
1973 -- The expression must appear in a default expression,
1974 -- (which in the initialization procedure is the right-hand
1975 -- side of an assignment), and not in a discriminant
1980 while Present (Par) loop
1981 exit when Nkind (Par) = N_Assignment_Statement;
1983 if Nkind (Par) = N_Component_Declaration then
1987 Par := Parent (Par);
1990 if Present (Par) then
1992 Make_Attribute_Reference (Loc,
1993 Prefix => Make_Identifier (Loc, Name_uInit),
1994 Attribute_Name => Attribute_Name (N)));
1996 Analyze_And_Resolve (N, Typ);
2001 -- If the prefix of an Access attribute is a dereference of an
2002 -- access parameter (or a renaming of such a dereference, or a
2003 -- subcomponent of such a dereference) and the context is a
2004 -- general access type (including the type of an object or
2005 -- component with an access_definition, but not the anonymous
2006 -- type of an access parameter or access discriminant), then
2007 -- apply an accessibility check to the access parameter. We used
2008 -- to rewrite the access parameter as a type conversion, but that
2009 -- could only be done if the immediate prefix of the Access
2010 -- attribute was the dereference, and didn't handle cases where
2011 -- the attribute is applied to a subcomponent of the dereference,
2012 -- since there's generally no available, appropriate access type
2013 -- to convert to in that case. The attribute is passed as the
2014 -- point to insert the check, because the access parameter may
2015 -- come from a renaming, possibly in a different scope, and the
2016 -- check must be associated with the attribute itself.
2018 elsif Id = Attribute_Access
2019 and then Nkind (Enc_Object) = N_Explicit_Dereference
2020 and then Is_Entity_Name (Prefix (Enc_Object))
2021 and then (Ekind (Btyp) = E_General_Access_Type
2022 or else Is_Local_Anonymous_Access (Btyp))
2023 and then Ekind (Entity (Prefix (Enc_Object))) in Formal_Kind
2024 and then Ekind (Etype (Entity (Prefix (Enc_Object))))
2025 = E_Anonymous_Access_Type
2026 and then Present (Extra_Accessibility
2027 (Entity (Prefix (Enc_Object))))
2029 Apply_Accessibility_Check (Prefix (Enc_Object), Typ, N);
2031 -- Ada 2005 (AI-251): If the designated type is an interface we
2032 -- add an implicit conversion to force the displacement of the
2033 -- pointer to reference the secondary dispatch table.
2035 elsif Is_Interface (Btyp_DDT)
2036 and then (Comes_From_Source (N)
2037 or else Comes_From_Source (Ref_Object)
2038 or else (Nkind (Ref_Object) in N_Has_Chars
2039 and then Chars (Ref_Object) = Name_uInit))
2041 if Nkind (Ref_Object) /= N_Explicit_Dereference then
2043 -- No implicit conversion required if types match, or if
2044 -- the prefix is the class_wide_type of the interface. In
2045 -- either case passing an object of the interface type has
2046 -- already set the pointer correctly.
2048 if Btyp_DDT = Etype (Ref_Object)
2049 or else (Is_Class_Wide_Type (Etype (Ref_Object))
2051 Class_Wide_Type (Btyp_DDT) = Etype (Ref_Object))
2056 Rewrite (Prefix (N),
2057 Convert_To (Btyp_DDT,
2058 New_Copy_Tree (Prefix (N))));
2060 Analyze_And_Resolve (Prefix (N), Btyp_DDT);
2063 -- When the object is an explicit dereference, convert the
2064 -- dereference's prefix.
2068 Obj_DDT : constant Entity_Id :=
2070 (Directly_Designated_Type
2071 (Etype (Prefix (Ref_Object))));
2073 -- No implicit conversion required if designated types
2074 -- match, or if we have an unrestricted access.
2076 if Obj_DDT /= Btyp_DDT
2077 and then Id /= Attribute_Unrestricted_Access
2078 and then not (Is_Class_Wide_Type (Obj_DDT)
2079 and then Etype (Obj_DDT) = Btyp_DDT)
2083 New_Copy_Tree (Prefix (Ref_Object))));
2084 Analyze_And_Resolve (N, Typ);
2095 -- Transforms 'Adjacent into a call to the floating-point attribute
2096 -- function Adjacent in Fat_xxx (where xxx is the root type)
2098 when Attribute_Adjacent =>
2099 Expand_Fpt_Attribute_RR (N);
2105 when Attribute_Address => Address : declare
2106 Task_Proc : Entity_Id;
2109 -- If the prefix is a task or a task type, the useful address is that
2110 -- of the procedure for the task body, i.e. the actual program unit.
2111 -- We replace the original entity with that of the procedure.
2113 if Is_Entity_Name (Pref)
2114 and then Is_Task_Type (Entity (Pref))
2116 Task_Proc := Next_Entity (Root_Type (Ptyp));
2118 while Present (Task_Proc) loop
2119 exit when Ekind (Task_Proc) = E_Procedure
2120 and then Etype (First_Formal (Task_Proc)) =
2121 Corresponding_Record_Type (Ptyp);
2122 Next_Entity (Task_Proc);
2125 if Present (Task_Proc) then
2126 Set_Entity (Pref, Task_Proc);
2127 Set_Etype (Pref, Etype (Task_Proc));
2130 -- Similarly, the address of a protected operation is the address
2131 -- of the corresponding protected body, regardless of the protected
2132 -- object from which it is selected.
2134 elsif Nkind (Pref) = N_Selected_Component
2135 and then Is_Subprogram (Entity (Selector_Name (Pref)))
2136 and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref))))
2140 External_Subprogram (Entity (Selector_Name (Pref))), Loc));
2142 elsif Nkind (Pref) = N_Explicit_Dereference
2143 and then Ekind (Ptyp) = E_Subprogram_Type
2144 and then Convention (Ptyp) = Convention_Protected
2146 -- The prefix is be a dereference of an access_to_protected_
2147 -- subprogram. The desired address is the second component of
2148 -- the record that represents the access.
2151 Addr : constant Entity_Id := Etype (N);
2152 Ptr : constant Node_Id := Prefix (Pref);
2153 T : constant Entity_Id :=
2154 Equivalent_Type (Base_Type (Etype (Ptr)));
2158 Unchecked_Convert_To (Addr,
2159 Make_Selected_Component (Loc,
2160 Prefix => Unchecked_Convert_To (T, Ptr),
2161 Selector_Name => New_Occurrence_Of (
2162 Next_Entity (First_Entity (T)), Loc))));
2164 Analyze_And_Resolve (N, Addr);
2167 -- Ada 2005 (AI-251): Class-wide interface objects are always
2168 -- "displaced" to reference the tag associated with the interface
2169 -- type. In order to obtain the real address of such objects we
2170 -- generate a call to a run-time subprogram that returns the base
2171 -- address of the object.
2173 -- This processing is not needed in the VM case, where dispatching
2174 -- issues are taken care of by the virtual machine.
2176 elsif Is_Class_Wide_Type (Ptyp)
2177 and then Is_Interface (Ptyp)
2178 and then Tagged_Type_Expansion
2179 and then not (Nkind (Pref) in N_Has_Entity
2180 and then Is_Subprogram (Entity (Pref)))
2183 Make_Function_Call (Loc,
2184 Name => New_Occurrence_Of (RTE (RE_Base_Address), Loc),
2185 Parameter_Associations => New_List (
2186 Relocate_Node (N))));
2191 -- Deal with packed array reference, other cases are handled by
2194 if Involves_Packed_Array_Reference (Pref) then
2195 Expand_Packed_Address_Reference (N);
2203 when Attribute_Alignment => Alignment : declare
2207 -- For class-wide types, X'Class'Alignment is transformed into a
2208 -- direct reference to the Alignment of the class type, so that the
2209 -- back end does not have to deal with the X'Class'Alignment
2212 if Is_Entity_Name (Pref)
2213 and then Is_Class_Wide_Type (Entity (Pref))
2215 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
2218 -- For x'Alignment applied to an object of a class wide type,
2219 -- transform X'Alignment into a call to the predefined primitive
2220 -- operation _Alignment applied to X.
2222 elsif Is_Class_Wide_Type (Ptyp) then
2224 Make_Attribute_Reference (Loc,
2226 Attribute_Name => Name_Tag);
2228 New_Node := Build_Get_Alignment (Loc, New_Node);
2230 -- Case where the context is a specific integer type with which
2231 -- the original attribute was compatible. The function has a
2232 -- specific type as well, so to preserve the compatibility we
2233 -- must convert explicitly.
2235 if Typ /= Standard_Integer then
2236 New_Node := Convert_To (Typ, New_Node);
2239 Rewrite (N, New_Node);
2240 Analyze_And_Resolve (N, Typ);
2243 -- For all other cases, we just have to deal with the case of
2244 -- the fact that the result can be universal.
2247 Apply_Universal_Integer_Attribute_Checks (N);
2255 -- We compute this if a packed array reference was present, otherwise we
2256 -- leave the computation up to the back end.
2258 when Attribute_Bit =>
2259 if Involves_Packed_Array_Reference (Pref) then
2260 Expand_Packed_Bit_Reference (N);
2262 Apply_Universal_Integer_Attribute_Checks (N);
2269 -- We compute this if a component clause was present, otherwise we leave
2270 -- the computation up to the back end, since we don't know what layout
2273 -- Note that the attribute can apply to a naked record component
2274 -- in generated code (i.e. the prefix is an identifier that
2275 -- references the component or discriminant entity).
2277 when Attribute_Bit_Position => Bit_Position : declare
2281 if Nkind (Pref) = N_Identifier then
2282 CE := Entity (Pref);
2284 CE := Entity (Selector_Name (Pref));
2287 if Known_Static_Component_Bit_Offset (CE) then
2289 Make_Integer_Literal (Loc,
2290 Intval => Component_Bit_Offset (CE)));
2291 Analyze_And_Resolve (N, Typ);
2294 Apply_Universal_Integer_Attribute_Checks (N);
2302 -- A reference to P'Body_Version or P'Version is expanded to
2305 -- pragma Import (C, Vnn, "uuuuT");
2307 -- Get_Version_String (Vnn)
2309 -- where uuuu is the unit name (dots replaced by double underscore)
2310 -- and T is B for the cases of Body_Version, or Version applied to a
2311 -- subprogram acting as its own spec, and S for Version applied to a
2312 -- subprogram spec or package. This sequence of code references the
2313 -- unsigned constant created in the main program by the binder.
2315 -- A special exception occurs for Standard, where the string returned
2316 -- is a copy of the library string in gnatvsn.ads.
2318 when Attribute_Body_Version | Attribute_Version => Version : declare
2319 E : constant Entity_Id := Make_Temporary (Loc, 'V');
2324 -- If not library unit, get to containing library unit
2326 Pent := Entity (Pref);
2327 while Pent /= Standard_Standard
2328 and then Scope (Pent) /= Standard_Standard
2329 and then not Is_Child_Unit (Pent)
2331 Pent := Scope (Pent);
2334 -- Special case Standard and Standard.ASCII
2336 if Pent = Standard_Standard or else Pent = Standard_ASCII then
2338 Make_String_Literal (Loc,
2339 Strval => Verbose_Library_Version));
2344 -- Build required string constant
2346 Get_Name_String (Get_Unit_Name (Pent));
2349 for J in 1 .. Name_Len - 2 loop
2350 if Name_Buffer (J) = '.' then
2351 Store_String_Chars ("__");
2353 Store_String_Char (Get_Char_Code (Name_Buffer (J)));
2357 -- Case of subprogram acting as its own spec, always use body
2359 if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification
2360 and then Nkind (Parent (Declaration_Node (Pent))) =
2362 and then Acts_As_Spec (Parent (Declaration_Node (Pent)))
2364 Store_String_Chars ("B");
2366 -- Case of no body present, always use spec
2368 elsif not Unit_Requires_Body (Pent) then
2369 Store_String_Chars ("S");
2371 -- Otherwise use B for Body_Version, S for spec
2373 elsif Id = Attribute_Body_Version then
2374 Store_String_Chars ("B");
2376 Store_String_Chars ("S");
2380 Lib.Version_Referenced (S);
2382 -- Insert the object declaration
2384 Insert_Actions (N, New_List (
2385 Make_Object_Declaration (Loc,
2386 Defining_Identifier => E,
2387 Object_Definition =>
2388 New_Occurrence_Of (RTE (RE_Unsigned), Loc))));
2390 -- Set entity as imported with correct external name
2392 Set_Is_Imported (E);
2393 Set_Interface_Name (E, Make_String_Literal (Loc, S));
2395 -- Set entity as internal to ensure proper Sprint output of its
2396 -- implicit importation.
2398 Set_Is_Internal (E);
2400 -- And now rewrite original reference
2403 Make_Function_Call (Loc,
2404 Name => New_Occurrence_Of (RTE (RE_Get_Version_String), Loc),
2405 Parameter_Associations => New_List (
2406 New_Occurrence_Of (E, Loc))));
2409 Analyze_And_Resolve (N, RTE (RE_Version_String));
2416 -- Transforms 'Ceiling into a call to the floating-point attribute
2417 -- function Ceiling in Fat_xxx (where xxx is the root type)
2419 when Attribute_Ceiling =>
2420 Expand_Fpt_Attribute_R (N);
2426 -- Transforms 'Callable attribute into a call to the Callable function
2428 when Attribute_Callable => Callable :
2430 -- We have an object of a task interface class-wide type as a prefix
2431 -- to Callable. Generate:
2432 -- callable (Task_Id (Pref._disp_get_task_id));
2434 if Ada_Version >= Ada_2005
2435 and then Ekind (Ptyp) = E_Class_Wide_Type
2436 and then Is_Interface (Ptyp)
2437 and then Is_Task_Interface (Ptyp)
2440 Make_Function_Call (Loc,
2442 New_Occurrence_Of (RTE (RE_Callable), Loc),
2443 Parameter_Associations => New_List (
2444 Make_Unchecked_Type_Conversion (Loc,
2446 New_Occurrence_Of (RTE (RO_ST_Task_Id), Loc),
2448 Make_Selected_Component (Loc,
2450 New_Copy_Tree (Pref),
2452 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
2456 Build_Call_With_Task (Pref, RTE (RE_Callable)));
2459 Analyze_And_Resolve (N, Standard_Boolean);
2466 -- Transforms 'Caller attribute into a call to either the
2467 -- Task_Entry_Caller or the Protected_Entry_Caller function.
2469 when Attribute_Caller => Caller : declare
2470 Id_Kind : constant Entity_Id := RTE (RO_AT_Task_Id);
2471 Ent : constant Entity_Id := Entity (Pref);
2472 Conctype : constant Entity_Id := Scope (Ent);
2473 Nest_Depth : Integer := 0;
2480 if Is_Protected_Type (Conctype) then
2481 case Corresponding_Runtime_Package (Conctype) is
2482 when System_Tasking_Protected_Objects_Entries =>
2485 (RTE (RE_Protected_Entry_Caller), Loc);
2487 when System_Tasking_Protected_Objects_Single_Entry =>
2490 (RTE (RE_Protected_Single_Entry_Caller), Loc);
2493 raise Program_Error;
2497 Unchecked_Convert_To (Id_Kind,
2498 Make_Function_Call (Loc,
2500 Parameter_Associations => New_List (
2502 (Find_Protection_Object (Current_Scope), Loc)))));
2507 -- Determine the nesting depth of the E'Caller attribute, that
2508 -- is, how many accept statements are nested within the accept
2509 -- statement for E at the point of E'Caller. The runtime uses
2510 -- this depth to find the specified entry call.
2512 for J in reverse 0 .. Scope_Stack.Last loop
2513 S := Scope_Stack.Table (J).Entity;
2515 -- We should not reach the scope of the entry, as it should
2516 -- already have been checked in Sem_Attr that this attribute
2517 -- reference is within a matching accept statement.
2519 pragma Assert (S /= Conctype);
2524 elsif Is_Entry (S) then
2525 Nest_Depth := Nest_Depth + 1;
2530 Unchecked_Convert_To (Id_Kind,
2531 Make_Function_Call (Loc,
2533 New_Occurrence_Of (RTE (RE_Task_Entry_Caller), Loc),
2534 Parameter_Associations => New_List (
2535 Make_Integer_Literal (Loc,
2536 Intval => Int (Nest_Depth))))));
2539 Analyze_And_Resolve (N, Id_Kind);
2546 -- Transforms 'Compose into a call to the floating-point attribute
2547 -- function Compose in Fat_xxx (where xxx is the root type)
2549 -- Note: we strictly should have special code here to deal with the
2550 -- case of absurdly negative arguments (less than Integer'First)
2551 -- which will return a (signed) zero value, but it hardly seems
2552 -- worth the effort. Absurdly large positive arguments will raise
2553 -- constraint error which is fine.
2555 when Attribute_Compose =>
2556 Expand_Fpt_Attribute_RI (N);
2562 when Attribute_Constrained => Constrained : declare
2563 Formal_Ent : constant Entity_Id := Param_Entity (Pref);
2565 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean;
2566 -- Ada 2005 (AI-363): Returns True if the object name Obj denotes a
2567 -- view of an aliased object whose subtype is constrained.
2569 ---------------------------------
2570 -- Is_Constrained_Aliased_View --
2571 ---------------------------------
2573 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean is
2577 if Is_Entity_Name (Obj) then
2580 if Present (Renamed_Object (E)) then
2581 return Is_Constrained_Aliased_View (Renamed_Object (E));
2583 return Is_Aliased (E) and then Is_Constrained (Etype (E));
2587 return Is_Aliased_View (Obj)
2589 (Is_Constrained (Etype (Obj))
2591 (Nkind (Obj) = N_Explicit_Dereference
2593 not Object_Type_Has_Constrained_Partial_View
2594 (Typ => Base_Type (Etype (Obj)),
2595 Scop => Current_Scope)));
2597 end Is_Constrained_Aliased_View;
2599 -- Start of processing for Constrained
2602 -- Reference to a parameter where the value is passed as an extra
2603 -- actual, corresponding to the extra formal referenced by the
2604 -- Extra_Constrained field of the corresponding formal. If this
2605 -- is an entry in-parameter, it is replaced by a constant renaming
2606 -- for which Extra_Constrained is never created.
2608 if Present (Formal_Ent)
2609 and then Ekind (Formal_Ent) /= E_Constant
2610 and then Present (Extra_Constrained (Formal_Ent))
2614 (Extra_Constrained (Formal_Ent), Sloc (N)));
2616 -- For variables with a Extra_Constrained field, we use the
2617 -- corresponding entity.
2619 elsif Nkind (Pref) = N_Identifier
2620 and then Ekind (Entity (Pref)) = E_Variable
2621 and then Present (Extra_Constrained (Entity (Pref)))
2625 (Extra_Constrained (Entity (Pref)), Sloc (N)));
2627 -- For all other entity names, we can tell at compile time
2629 elsif Is_Entity_Name (Pref) then
2631 Ent : constant Entity_Id := Entity (Pref);
2635 -- (RM J.4) obsolescent cases
2637 if Is_Type (Ent) then
2641 if Is_Private_Type (Ent) then
2642 Res := not Has_Discriminants (Ent)
2643 or else Is_Constrained (Ent);
2645 -- It not a private type, must be a generic actual type
2646 -- that corresponded to a private type. We know that this
2647 -- correspondence holds, since otherwise the reference
2648 -- within the generic template would have been illegal.
2651 if Is_Composite_Type (Underlying_Type (Ent)) then
2652 Res := Is_Constrained (Ent);
2658 -- If the prefix is not a variable or is aliased, then
2659 -- definitely true; if it's a formal parameter without an
2660 -- associated extra formal, then treat it as constrained.
2662 -- Ada 2005 (AI-363): An aliased prefix must be known to be
2663 -- constrained in order to set the attribute to True.
2665 elsif not Is_Variable (Pref)
2666 or else Present (Formal_Ent)
2667 or else (Ada_Version < Ada_2005
2668 and then Is_Aliased_View (Pref))
2669 or else (Ada_Version >= Ada_2005
2670 and then Is_Constrained_Aliased_View (Pref))
2674 -- Variable case, look at type to see if it is constrained.
2675 -- Note that the one case where this is not accurate (the
2676 -- procedure formal case), has been handled above.
2678 -- We use the Underlying_Type here (and below) in case the
2679 -- type is private without discriminants, but the full type
2680 -- has discriminants. This case is illegal, but we generate it
2681 -- internally for passing to the Extra_Constrained parameter.
2684 -- In Ada 2012, test for case of a limited tagged type, in
2685 -- which case the attribute is always required to return
2686 -- True. The underlying type is tested, to make sure we also
2687 -- return True for cases where there is an unconstrained
2688 -- object with an untagged limited partial view which has
2689 -- defaulted discriminants (such objects always produce a
2690 -- False in earlier versions of Ada). (Ada 2012: AI05-0214)
2692 Res := Is_Constrained (Underlying_Type (Etype (Ent)))
2694 (Ada_Version >= Ada_2012
2695 and then Is_Tagged_Type (Underlying_Type (Ptyp))
2696 and then Is_Limited_Type (Ptyp));
2699 Rewrite (N, New_Occurrence_Of (Boolean_Literals (Res), Loc));
2702 -- Prefix is not an entity name. These are also cases where we can
2703 -- always tell at compile time by looking at the form and type of the
2704 -- prefix. If an explicit dereference of an object with constrained
2705 -- partial view, this is unconstrained (Ada 2005: AI95-0363). If the
2706 -- underlying type is a limited tagged type, then Constrained is
2707 -- required to always return True (Ada 2012: AI05-0214).
2713 not Is_Variable (Pref)
2715 (Nkind (Pref) = N_Explicit_Dereference
2717 not Object_Type_Has_Constrained_Partial_View
2718 (Typ => Base_Type (Ptyp),
2719 Scop => Current_Scope))
2720 or else Is_Constrained (Underlying_Type (Ptyp))
2721 or else (Ada_Version >= Ada_2012
2722 and then Is_Tagged_Type (Underlying_Type (Ptyp))
2723 and then Is_Limited_Type (Ptyp))),
2727 Analyze_And_Resolve (N, Standard_Boolean);
2734 -- Transforms 'Copy_Sign into a call to the floating-point attribute
2735 -- function Copy_Sign in Fat_xxx (where xxx is the root type)
2737 when Attribute_Copy_Sign =>
2738 Expand_Fpt_Attribute_RR (N);
2744 -- Transforms 'Count attribute into a call to the Count function
2746 when Attribute_Count => Count : declare
2748 Conctyp : Entity_Id;
2750 Entry_Id : Entity_Id;
2755 -- If the prefix is a member of an entry family, retrieve both
2756 -- entry name and index. For a simple entry there is no index.
2758 if Nkind (Pref) = N_Indexed_Component then
2759 Entnam := Prefix (Pref);
2760 Index := First (Expressions (Pref));
2766 Entry_Id := Entity (Entnam);
2768 -- Find the concurrent type in which this attribute is referenced
2769 -- (there had better be one).
2771 Conctyp := Current_Scope;
2772 while not Is_Concurrent_Type (Conctyp) loop
2773 Conctyp := Scope (Conctyp);
2778 if Is_Protected_Type (Conctyp) then
2779 case Corresponding_Runtime_Package (Conctyp) is
2780 when System_Tasking_Protected_Objects_Entries =>
2781 Name := New_Occurrence_Of (RTE (RE_Protected_Count), Loc);
2784 Make_Function_Call (Loc,
2786 Parameter_Associations => New_List (
2788 (Find_Protection_Object (Current_Scope), Loc),
2789 Entry_Index_Expression
2790 (Loc, Entry_Id, Index, Scope (Entry_Id))));
2792 when System_Tasking_Protected_Objects_Single_Entry =>
2794 New_Occurrence_Of (RTE (RE_Protected_Count_Entry), Loc);
2797 Make_Function_Call (Loc,
2799 Parameter_Associations => New_List (
2801 (Find_Protection_Object (Current_Scope), Loc)));
2804 raise Program_Error;
2811 Make_Function_Call (Loc,
2812 Name => New_Occurrence_Of (RTE (RE_Task_Count), Loc),
2813 Parameter_Associations => New_List (
2814 Entry_Index_Expression (Loc,
2815 Entry_Id, Index, Scope (Entry_Id))));
2818 -- The call returns type Natural but the context is universal integer
2819 -- so any integer type is allowed. The attribute was already resolved
2820 -- so its Etype is the required result type. If the base type of the
2821 -- context type is other than Standard.Integer we put in a conversion
2822 -- to the required type. This can be a normal typed conversion since
2823 -- both input and output types of the conversion are integer types
2825 if Base_Type (Typ) /= Base_Type (Standard_Integer) then
2826 Rewrite (N, Convert_To (Typ, Call));
2831 Analyze_And_Resolve (N, Typ);
2834 ---------------------
2835 -- Descriptor_Size --
2836 ---------------------
2838 when Attribute_Descriptor_Size =>
2840 -- Attribute Descriptor_Size is handled by the back end when applied
2841 -- to an unconstrained array type.
2843 if Is_Array_Type (Ptyp)
2844 and then not Is_Constrained (Ptyp)
2846 Apply_Universal_Integer_Attribute_Checks (N);
2848 -- For any other type, the descriptor size is 0 because there is no
2849 -- actual descriptor, but the result is not formally static.
2852 Rewrite (N, Make_Integer_Literal (Loc, 0));
2854 Set_Is_Static_Expression (N, False);
2861 -- This processing is shared by Elab_Spec
2863 -- What we do is to insert the following declarations
2866 -- pragma Import (C, enn, "name___elabb/s");
2868 -- and then the Elab_Body/Spec attribute is replaced by a reference
2869 -- to this defining identifier.
2871 when Attribute_Elab_Body |
2872 Attribute_Elab_Spec =>
2874 -- Leave attribute unexpanded in CodePeer mode: the gnat2scil
2875 -- back-end knows how to handle these attributes directly.
2877 if CodePeer_Mode then
2882 Ent : constant Entity_Id := Make_Temporary (Loc, 'E');
2886 procedure Make_Elab_String (Nod : Node_Id);
2887 -- Given Nod, an identifier, or a selected component, put the
2888 -- image into the current string literal, with double underline
2889 -- between components.
2891 ----------------------
2892 -- Make_Elab_String --
2893 ----------------------
2895 procedure Make_Elab_String (Nod : Node_Id) is
2897 if Nkind (Nod) = N_Selected_Component then
2898 Make_Elab_String (Prefix (Nod));
2899 Store_String_Char ('_');
2900 Store_String_Char ('_');
2901 Get_Name_String (Chars (Selector_Name (Nod)));
2904 pragma Assert (Nkind (Nod) = N_Identifier);
2905 Get_Name_String (Chars (Nod));
2908 Store_String_Chars (Name_Buffer (1 .. Name_Len));
2909 end Make_Elab_String;
2911 -- Start of processing for Elab_Body/Elab_Spec
2914 -- First we need to prepare the string literal for the name of
2915 -- the elaboration routine to be referenced.
2918 Make_Elab_String (Pref);
2919 Store_String_Chars ("___elab");
2920 Lang := Make_Identifier (Loc, Name_C);
2922 if Id = Attribute_Elab_Body then
2923 Store_String_Char ('b');
2925 Store_String_Char ('s');
2930 Insert_Actions (N, New_List (
2931 Make_Subprogram_Declaration (Loc,
2933 Make_Procedure_Specification (Loc,
2934 Defining_Unit_Name => Ent)),
2937 Chars => Name_Import,
2938 Pragma_Argument_Associations => New_List (
2939 Make_Pragma_Argument_Association (Loc, Expression => Lang),
2941 Make_Pragma_Argument_Association (Loc,
2942 Expression => Make_Identifier (Loc, Chars (Ent))),
2944 Make_Pragma_Argument_Association (Loc,
2945 Expression => Make_String_Literal (Loc, Str))))));
2947 Set_Entity (N, Ent);
2948 Rewrite (N, New_Occurrence_Of (Ent, Loc));
2951 --------------------
2952 -- Elab_Subp_Body --
2953 --------------------
2955 -- Always ignored. In CodePeer mode, gnat2scil knows how to handle
2956 -- this attribute directly, and if we are not in CodePeer mode it is
2957 -- entirely ignored ???
2959 when Attribute_Elab_Subp_Body =>
2966 -- Elaborated is always True for preelaborated units, predefined units,
2967 -- pure units and units which have Elaborate_Body pragmas. These units
2968 -- have no elaboration entity.
2970 -- Note: The Elaborated attribute is never passed to the back end
2972 when Attribute_Elaborated => Elaborated : declare
2973 Ent : constant Entity_Id := Entity (Pref);
2976 if Present (Elaboration_Entity (Ent)) then
2980 New_Occurrence_Of (Elaboration_Entity (Ent), Loc),
2982 Make_Integer_Literal (Loc, Uint_0)));
2983 Analyze_And_Resolve (N, Typ);
2985 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
2993 when Attribute_Enum_Rep => Enum_Rep :
2995 -- X'Enum_Rep (Y) expands to
2999 -- This is simply a direct conversion from the enumeration type to
3000 -- the target integer type, which is treated by the back end as a
3001 -- normal integer conversion, treating the enumeration type as an
3002 -- integer, which is exactly what we want. We set Conversion_OK to
3003 -- make sure that the analyzer does not complain about what otherwise
3004 -- might be an illegal conversion.
3006 if Is_Non_Empty_List (Exprs) then
3008 OK_Convert_To (Typ, Relocate_Node (First (Exprs))));
3010 -- X'Enum_Rep where X is an enumeration literal is replaced by
3011 -- the literal value.
3013 elsif Ekind (Entity (Pref)) = E_Enumeration_Literal then
3015 Make_Integer_Literal (Loc, Enumeration_Rep (Entity (Pref))));
3017 -- If this is a renaming of a literal, recover the representation
3020 elsif Ekind (Entity (Pref)) = E_Constant
3021 and then Present (Renamed_Object (Entity (Pref)))
3023 Ekind (Entity (Renamed_Object (Entity (Pref))))
3024 = E_Enumeration_Literal
3027 Make_Integer_Literal (Loc,
3028 Enumeration_Rep (Entity (Renamed_Object (Entity (Pref))))));
3030 -- X'Enum_Rep where X is an object does a direct unchecked conversion
3031 -- of the object value, as described for the type case above.
3035 OK_Convert_To (Typ, Relocate_Node (Pref)));
3039 Analyze_And_Resolve (N, Typ);
3046 when Attribute_Enum_Val => Enum_Val : declare
3048 Btyp : constant Entity_Id := Base_Type (Ptyp);
3051 -- X'Enum_Val (Y) expands to
3053 -- [constraint_error when _rep_to_pos (Y, False) = -1, msg]
3056 Expr := Unchecked_Convert_To (Ptyp, First (Exprs));
3059 Make_Raise_Constraint_Error (Loc,
3063 Make_Function_Call (Loc,
3065 New_Occurrence_Of (TSS (Btyp, TSS_Rep_To_Pos), Loc),
3066 Parameter_Associations => New_List (
3067 Relocate_Node (Duplicate_Subexpr (Expr)),
3068 New_Occurrence_Of (Standard_False, Loc))),
3070 Right_Opnd => Make_Integer_Literal (Loc, -1)),
3071 Reason => CE_Range_Check_Failed));
3074 Analyze_And_Resolve (N, Ptyp);
3081 -- Transforms 'Exponent into a call to the floating-point attribute
3082 -- function Exponent in Fat_xxx (where xxx is the root type)
3084 when Attribute_Exponent =>
3085 Expand_Fpt_Attribute_R (N);
3091 -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
3093 when Attribute_External_Tag => External_Tag :
3096 Make_Function_Call (Loc,
3097 Name => New_Occurrence_Of (RTE (RE_External_Tag), Loc),
3098 Parameter_Associations => New_List (
3099 Make_Attribute_Reference (Loc,
3100 Attribute_Name => Name_Tag,
3101 Prefix => Prefix (N)))));
3103 Analyze_And_Resolve (N, Standard_String);
3110 when Attribute_First =>
3112 -- If the prefix type is a constrained packed array type which
3113 -- already has a Packed_Array_Impl_Type representation defined, then
3114 -- replace this attribute with a direct reference to 'First of the
3115 -- appropriate index subtype (since otherwise the back end will try
3116 -- to give us the value of 'First for this implementation type).
3118 if Is_Constrained_Packed_Array (Ptyp) then
3120 Make_Attribute_Reference (Loc,
3121 Attribute_Name => Name_First,
3123 New_Occurrence_Of (Get_Index_Subtype (N), Loc)));
3124 Analyze_And_Resolve (N, Typ);
3126 -- For access type, apply access check as needed
3128 elsif Is_Access_Type (Ptyp) then
3129 Apply_Access_Check (N);
3131 -- For scalar type, if low bound is a reference to an entity, just
3132 -- replace with a direct reference. Note that we can only have a
3133 -- reference to a constant entity at this stage, anything else would
3134 -- have already been rewritten.
3136 elsif Is_Scalar_Type (Ptyp) then
3138 Lo : constant Node_Id := Type_Low_Bound (Ptyp);
3140 if Is_Entity_Name (Lo) then
3141 Rewrite (N, New_Occurrence_Of (Entity (Lo), Loc));
3150 -- Compute this if component clause was present, otherwise we leave the
3151 -- computation to be completed in the back-end, since we don't know what
3152 -- layout will be chosen.
3154 when Attribute_First_Bit => First_Bit_Attr : declare
3155 CE : constant Entity_Id := Entity (Selector_Name (Pref));
3158 -- In Ada 2005 (or later) if we have the non-default bit order, then
3159 -- we return the original value as given in the component clause
3160 -- (RM 2005 13.5.2(3/2)).
3162 if Present (Component_Clause (CE))
3163 and then Ada_Version >= Ada_2005
3164 and then Reverse_Bit_Order (Scope (CE))
3167 Make_Integer_Literal (Loc,
3168 Intval => Expr_Value (First_Bit (Component_Clause (CE)))));
3169 Analyze_And_Resolve (N, Typ);
3171 -- Otherwise (Ada 83/95 or Ada 2005 or later with default bit order),
3172 -- rewrite with normalized value if we know it statically.
3174 elsif Known_Static_Component_Bit_Offset (CE) then
3176 Make_Integer_Literal (Loc,
3177 Component_Bit_Offset (CE) mod System_Storage_Unit));
3178 Analyze_And_Resolve (N, Typ);
3180 -- Otherwise left to back end, just do universal integer checks
3183 Apply_Universal_Integer_Attribute_Checks (N);
3193 -- fixtype'Fixed_Value (integer-value)
3197 -- fixtype(integer-value)
3199 -- We do all the required analysis of the conversion here, because we do
3200 -- not want this to go through the fixed-point conversion circuits. Note
3201 -- that the back end always treats fixed-point as equivalent to the
3202 -- corresponding integer type anyway.
3204 when Attribute_Fixed_Value => Fixed_Value :
3207 Make_Type_Conversion (Loc,
3208 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
3209 Expression => Relocate_Node (First (Exprs))));
3210 Set_Etype (N, Entity (Pref));
3213 -- Note: it might appear that a properly analyzed unchecked conversion
3214 -- would be just fine here, but that's not the case, since the full
3215 -- range checks performed by the following call are critical.
3217 Apply_Type_Conversion_Checks (N);
3224 -- Transforms 'Floor into a call to the floating-point attribute
3225 -- function Floor in Fat_xxx (where xxx is the root type)
3227 when Attribute_Floor =>
3228 Expand_Fpt_Attribute_R (N);
3234 -- For the fixed-point type Typ:
3240 -- Result_Type (System.Fore (Universal_Real (Type'First)),
3241 -- Universal_Real (Type'Last))
3243 -- Note that we know that the type is a non-static subtype, or Fore
3244 -- would have itself been computed dynamically in Eval_Attribute.
3246 when Attribute_Fore => Fore : begin
3249 Make_Function_Call (Loc,
3250 Name => New_Occurrence_Of (RTE (RE_Fore), Loc),
3252 Parameter_Associations => New_List (
3253 Convert_To (Universal_Real,
3254 Make_Attribute_Reference (Loc,
3255 Prefix => New_Occurrence_Of (Ptyp, Loc),
3256 Attribute_Name => Name_First)),
3258 Convert_To (Universal_Real,
3259 Make_Attribute_Reference (Loc,
3260 Prefix => New_Occurrence_Of (Ptyp, Loc),
3261 Attribute_Name => Name_Last))))));
3263 Analyze_And_Resolve (N, Typ);
3270 -- Transforms 'Fraction into a call to the floating-point attribute
3271 -- function Fraction in Fat_xxx (where xxx is the root type)
3273 when Attribute_Fraction =>
3274 Expand_Fpt_Attribute_R (N);
3280 when Attribute_From_Any => From_Any : declare
3281 P_Type : constant Entity_Id := Etype (Pref);
3282 Decls : constant List_Id := New_List;
3285 Build_From_Any_Call (P_Type,
3286 Relocate_Node (First (Exprs)),
3288 Insert_Actions (N, Decls);
3289 Analyze_And_Resolve (N, P_Type);
3292 ----------------------
3293 -- Has_Same_Storage --
3294 ----------------------
3296 when Attribute_Has_Same_Storage => Has_Same_Storage : declare
3297 Loc : constant Source_Ptr := Sloc (N);
3299 X : constant Node_Id := Prefix (N);
3300 Y : constant Node_Id := First (Expressions (N));
3303 X_Addr, Y_Addr : Node_Id;
3304 -- Rhe expressions for their addresses
3306 X_Size, Y_Size : Node_Id;
3307 -- Rhe expressions for their sizes
3310 -- The attribute is expanded as:
3312 -- (X'address = Y'address)
3313 -- and then (X'Size = Y'Size)
3315 -- If both arguments have the same Etype the second conjunct can be
3319 Make_Attribute_Reference (Loc,
3320 Attribute_Name => Name_Address,
3321 Prefix => New_Copy_Tree (X));
3324 Make_Attribute_Reference (Loc,
3325 Attribute_Name => Name_Address,
3326 Prefix => New_Copy_Tree (Y));
3329 Make_Attribute_Reference (Loc,
3330 Attribute_Name => Name_Size,
3331 Prefix => New_Copy_Tree (X));
3334 Make_Attribute_Reference (Loc,
3335 Attribute_Name => Name_Size,
3336 Prefix => New_Copy_Tree (Y));
3338 if Etype (X) = Etype (Y) then
3341 Left_Opnd => X_Addr,
3342 Right_Opnd => Y_Addr)));
3348 Left_Opnd => X_Addr,
3349 Right_Opnd => Y_Addr),
3352 Left_Opnd => X_Size,
3353 Right_Opnd => Y_Size)));
3356 Analyze_And_Resolve (N, Standard_Boolean);
3357 end Has_Same_Storage;
3363 -- For an exception returns a reference to the exception data:
3364 -- Exception_Id!(Prefix'Reference)
3366 -- For a task it returns a reference to the _task_id component of
3367 -- corresponding record:
3369 -- taskV!(Prefix)._Task_Id, converted to the type Task_Id defined
3371 -- in Ada.Task_Identification
3373 when Attribute_Identity => Identity : declare
3374 Id_Kind : Entity_Id;
3377 if Ptyp = Standard_Exception_Type then
3378 Id_Kind := RTE (RE_Exception_Id);
3380 if Present (Renamed_Object (Entity (Pref))) then
3381 Set_Entity (Pref, Renamed_Object (Entity (Pref)));
3385 Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref)));
3387 Id_Kind := RTE (RO_AT_Task_Id);
3389 -- If the prefix is a task interface, the Task_Id is obtained
3390 -- dynamically through a dispatching call, as for other task
3391 -- attributes applied to interfaces.
3393 if Ada_Version >= Ada_2005
3394 and then Ekind (Ptyp) = E_Class_Wide_Type
3395 and then Is_Interface (Ptyp)
3396 and then Is_Task_Interface (Ptyp)
3399 Unchecked_Convert_To (Id_Kind,
3400 Make_Selected_Component (Loc,
3402 New_Copy_Tree (Pref),
3404 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))));
3408 Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
3412 Analyze_And_Resolve (N, Id_Kind);
3419 -- Image attribute is handled in separate unit Exp_Imgv
3421 when Attribute_Image =>
3422 Exp_Imgv.Expand_Image_Attribute (N);
3428 -- X'Img is expanded to typ'Image (X), where typ is the type of X
3430 when Attribute_Img => Img :
3433 Make_Attribute_Reference (Loc,
3434 Prefix => New_Occurrence_Of (Ptyp, Loc),
3435 Attribute_Name => Name_Image,
3436 Expressions => New_List (Relocate_Node (Pref))));
3438 Analyze_And_Resolve (N, Standard_String);
3445 when Attribute_Input => Input : declare
3446 P_Type : constant Entity_Id := Entity (Pref);
3447 B_Type : constant Entity_Id := Base_Type (P_Type);
3448 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3449 Strm : constant Node_Id := First (Exprs);
3457 Cntrl : Node_Id := Empty;
3458 -- Value for controlling argument in call. Always Empty except in
3459 -- the dispatching (class-wide type) case, where it is a reference
3460 -- to the dummy object initialized to the right internal tag.
3462 procedure Freeze_Stream_Subprogram (F : Entity_Id);
3463 -- The expansion of the attribute reference may generate a call to
3464 -- a user-defined stream subprogram that is frozen by the call. This
3465 -- can lead to access-before-elaboration problem if the reference
3466 -- appears in an object declaration and the subprogram body has not
3467 -- been seen. The freezing of the subprogram requires special code
3468 -- because it appears in an expanded context where expressions do
3469 -- not freeze their constituents.
3471 ------------------------------
3472 -- Freeze_Stream_Subprogram --
3473 ------------------------------
3475 procedure Freeze_Stream_Subprogram (F : Entity_Id) is
3476 Decl : constant Node_Id := Unit_Declaration_Node (F);
3480 -- If this is user-defined subprogram, the corresponding
3481 -- stream function appears as a renaming-as-body, and the
3482 -- user subprogram must be retrieved by tree traversal.
3485 and then Nkind (Decl) = N_Subprogram_Declaration
3486 and then Present (Corresponding_Body (Decl))
3488 Bod := Corresponding_Body (Decl);
3490 if Nkind (Unit_Declaration_Node (Bod)) =
3491 N_Subprogram_Renaming_Declaration
3493 Set_Is_Frozen (Entity (Name (Unit_Declaration_Node (Bod))));
3496 end Freeze_Stream_Subprogram;
3498 -- Start of processing for Input
3501 -- If no underlying type, we have an error that will be diagnosed
3502 -- elsewhere, so here we just completely ignore the expansion.
3508 -- Stream operations can appear in user code even if the restriction
3509 -- No_Streams is active (for example, when instantiating a predefined
3510 -- container). In that case rewrite the attribute as a Raise to
3511 -- prevent any run-time use.
3513 if Restriction_Active (No_Streams) then
3515 Make_Raise_Program_Error (Sloc (N),
3516 Reason => PE_Stream_Operation_Not_Allowed));
3517 Set_Etype (N, B_Type);
3521 -- If there is a TSS for Input, just call it
3523 Fname := Find_Stream_Subprogram (P_Type, TSS_Stream_Input);
3525 if Present (Fname) then
3529 -- If there is a Stream_Convert pragma, use it, we rewrite
3531 -- sourcetyp'Input (stream)
3535 -- sourcetyp (streamread (strmtyp'Input (stream)));
3537 -- where streamread is the given Read function that converts an
3538 -- argument of type strmtyp to type sourcetyp or a type from which
3539 -- it is derived (extra conversion required for the derived case).
3541 Prag := Get_Stream_Convert_Pragma (P_Type);
3543 if Present (Prag) then
3544 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
3545 Rfunc := Entity (Expression (Arg2));
3549 Make_Function_Call (Loc,
3550 Name => New_Occurrence_Of (Rfunc, Loc),
3551 Parameter_Associations => New_List (
3552 Make_Attribute_Reference (Loc,
3555 (Etype (First_Formal (Rfunc)), Loc),
3556 Attribute_Name => Name_Input,
3557 Expressions => Exprs)))));
3559 Analyze_And_Resolve (N, B_Type);
3564 elsif Is_Elementary_Type (U_Type) then
3566 -- A special case arises if we have a defined _Read routine,
3567 -- since in this case we are required to call this routine.
3569 if Present (TSS (Base_Type (U_Type), TSS_Stream_Read)) then
3570 Build_Record_Or_Elementary_Input_Function
3571 (Loc, U_Type, Decl, Fname);
3572 Insert_Action (N, Decl);
3574 -- For normal cases, we call the I_xxx routine directly
3577 Rewrite (N, Build_Elementary_Input_Call (N));
3578 Analyze_And_Resolve (N, P_Type);
3584 elsif Is_Array_Type (U_Type) then
3585 Build_Array_Input_Function (Loc, U_Type, Decl, Fname);
3586 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3588 -- Dispatching case with class-wide type
3590 elsif Is_Class_Wide_Type (P_Type) then
3592 -- No need to do anything else compiling under restriction
3593 -- No_Dispatching_Calls. During the semantic analysis we
3594 -- already notified such violation.
3596 if Restriction_Active (No_Dispatching_Calls) then
3601 Rtyp : constant Entity_Id := Root_Type (P_Type);
3605 -- Read the internal tag (RM 13.13.2(34)) and use it to
3606 -- initialize a dummy tag value:
3608 -- Descendant_Tag (String'Input (Strm), P_Type);
3610 -- This value is used only to provide a controlling
3611 -- argument for the eventual _Input call. Descendant_Tag is
3612 -- called rather than Internal_Tag to ensure that we have a
3613 -- tag for a type that is descended from the prefix type and
3614 -- declared at the same accessibility level (the exception
3615 -- Tag_Error will be raised otherwise). The level check is
3616 -- required for Ada 2005 because tagged types can be
3617 -- extended in nested scopes (AI-344).
3619 -- Note: we used to generate an explicit declaration of a
3620 -- constant Ada.Tags.Tag object, and use an occurrence of
3621 -- this constant in Cntrl, but this caused a secondary stack
3625 Make_Function_Call (Loc,
3627 New_Occurrence_Of (RTE (RE_Descendant_Tag), Loc),
3628 Parameter_Associations => New_List (
3629 Make_Attribute_Reference (Loc,
3631 New_Occurrence_Of (Standard_String, Loc),
3632 Attribute_Name => Name_Input,
3633 Expressions => New_List (
3634 Relocate_Node (Duplicate_Subexpr (Strm)))),
3635 Make_Attribute_Reference (Loc,
3636 Prefix => New_Occurrence_Of (P_Type, Loc),
3637 Attribute_Name => Name_Tag)));
3638 Set_Etype (Expr, RTE (RE_Tag));
3640 -- Now we need to get the entity for the call, and construct
3641 -- a function call node, where we preset a reference to Dnn
3642 -- as the controlling argument (doing an unchecked convert
3643 -- to the class-wide tagged type to make it look like a real
3646 Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input);
3647 Cntrl := Unchecked_Convert_To (P_Type, Expr);
3648 Set_Etype (Cntrl, P_Type);
3649 Set_Parent (Cntrl, N);
3652 -- For tagged types, use the primitive Input function
3654 elsif Is_Tagged_Type (U_Type) then
3655 Fname := Find_Prim_Op (U_Type, TSS_Stream_Input);
3657 -- All other record type cases, including protected records. The
3658 -- latter only arise for expander generated code for handling
3659 -- shared passive partition access.
3663 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3665 -- Ada 2005 (AI-216): Program_Error is raised executing default
3666 -- implementation of the Input attribute of an unchecked union
3667 -- type if the type lacks default discriminant values.
3669 if Is_Unchecked_Union (Base_Type (U_Type))
3670 and then No (Discriminant_Constraint (U_Type))
3673 Make_Raise_Program_Error (Loc,
3674 Reason => PE_Unchecked_Union_Restriction));
3679 -- Build the type's Input function, passing the subtype rather
3680 -- than its base type, because checks are needed in the case of
3681 -- constrained discriminants (see Ada 2012 AI05-0192).
3683 Build_Record_Or_Elementary_Input_Function
3684 (Loc, U_Type, Decl, Fname);
3685 Insert_Action (N, Decl);
3687 if Nkind (Parent (N)) = N_Object_Declaration
3688 and then Is_Record_Type (U_Type)
3690 -- The stream function may contain calls to user-defined
3691 -- Read procedures for individual components.
3698 Comp := First_Component (U_Type);
3699 while Present (Comp) loop
3701 Find_Stream_Subprogram
3702 (Etype (Comp), TSS_Stream_Read);
3704 if Present (Func) then
3705 Freeze_Stream_Subprogram (Func);
3708 Next_Component (Comp);
3715 -- If we fall through, Fname is the function to be called. The result
3716 -- is obtained by calling the appropriate function, then converting
3717 -- the result. The conversion does a subtype check.
3720 Make_Function_Call (Loc,
3721 Name => New_Occurrence_Of (Fname, Loc),
3722 Parameter_Associations => New_List (
3723 Relocate_Node (Strm)));
3725 Set_Controlling_Argument (Call, Cntrl);
3726 Rewrite (N, Unchecked_Convert_To (P_Type, Call));
3727 Analyze_And_Resolve (N, P_Type);
3729 if Nkind (Parent (N)) = N_Object_Declaration then
3730 Freeze_Stream_Subprogram (Fname);
3740 -- inttype'Fixed_Value (fixed-value)
3744 -- inttype(integer-value))
3746 -- we do all the required analysis of the conversion here, because we do
3747 -- not want this to go through the fixed-point conversion circuits. Note
3748 -- that the back end always treats fixed-point as equivalent to the
3749 -- corresponding integer type anyway.
3751 when Attribute_Integer_Value => Integer_Value :
3754 Make_Type_Conversion (Loc,
3755 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
3756 Expression => Relocate_Node (First (Exprs))));
3757 Set_Etype (N, Entity (Pref));
3760 -- Note: it might appear that a properly analyzed unchecked conversion
3761 -- would be just fine here, but that's not the case, since the full
3762 -- range checks performed by the following call are critical.
3764 Apply_Type_Conversion_Checks (N);
3771 when Attribute_Invalid_Value =>
3772 Rewrite (N, Get_Simple_Init_Val (Ptyp, N));
3778 when Attribute_Last =>
3780 -- If the prefix type is a constrained packed array type which
3781 -- already has a Packed_Array_Impl_Type representation defined, then
3782 -- replace this attribute with a direct reference to 'Last of the
3783 -- appropriate index subtype (since otherwise the back end will try
3784 -- to give us the value of 'Last for this implementation type).
3786 if Is_Constrained_Packed_Array (Ptyp) then
3788 Make_Attribute_Reference (Loc,
3789 Attribute_Name => Name_Last,
3790 Prefix => New_Occurrence_Of (Get_Index_Subtype (N), Loc)));
3791 Analyze_And_Resolve (N, Typ);
3793 -- For access type, apply access check as needed
3795 elsif Is_Access_Type (Ptyp) then
3796 Apply_Access_Check (N);
3798 -- For scalar type, if low bound is a reference to an entity, just
3799 -- replace with a direct reference. Note that we can only have a
3800 -- reference to a constant entity at this stage, anything else would
3801 -- have already been rewritten.
3803 elsif Is_Scalar_Type (Ptyp) then
3805 Hi : constant Node_Id := Type_High_Bound (Ptyp);
3807 if Is_Entity_Name (Hi) then
3808 Rewrite (N, New_Occurrence_Of (Entity (Hi), Loc));
3817 -- We compute this if a component clause was present, otherwise we leave
3818 -- the computation up to the back end, since we don't know what layout
3821 when Attribute_Last_Bit => Last_Bit_Attr : declare
3822 CE : constant Entity_Id := Entity (Selector_Name (Pref));
3825 -- In Ada 2005 (or later) if we have the non-default bit order, then
3826 -- we return the original value as given in the component clause
3827 -- (RM 2005 13.5.2(3/2)).
3829 if Present (Component_Clause (CE))
3830 and then Ada_Version >= Ada_2005
3831 and then Reverse_Bit_Order (Scope (CE))
3834 Make_Integer_Literal (Loc,
3835 Intval => Expr_Value (Last_Bit (Component_Clause (CE)))));
3836 Analyze_And_Resolve (N, Typ);
3838 -- Otherwise (Ada 83/95 or Ada 2005 or later with default bit order),
3839 -- rewrite with normalized value if we know it statically.
3841 elsif Known_Static_Component_Bit_Offset (CE)
3842 and then Known_Static_Esize (CE)
3845 Make_Integer_Literal (Loc,
3846 Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit)
3848 Analyze_And_Resolve (N, Typ);
3850 -- Otherwise leave to back end, just apply universal integer checks
3853 Apply_Universal_Integer_Attribute_Checks (N);
3861 -- Transforms 'Leading_Part into a call to the floating-point attribute
3862 -- function Leading_Part in Fat_xxx (where xxx is the root type)
3864 -- Note: strictly, we should generate special case code to deal with
3865 -- absurdly large positive arguments (greater than Integer'Last), which
3866 -- result in returning the first argument unchanged, but it hardly seems
3867 -- worth the effort. We raise constraint error for absurdly negative
3868 -- arguments which is fine.
3870 when Attribute_Leading_Part =>
3871 Expand_Fpt_Attribute_RI (N);
3877 when Attribute_Length => Length : declare
3882 -- Processing for packed array types
3884 if Is_Array_Type (Ptyp) and then Is_Packed (Ptyp) then
3885 Ityp := Get_Index_Subtype (N);
3887 -- If the index type, Ityp, is an enumeration type with holes,
3888 -- then we calculate X'Length explicitly using
3891 -- (0, Ityp'Pos (X'Last (N)) -
3892 -- Ityp'Pos (X'First (N)) + 1);
3894 -- Since the bounds in the template are the representation values
3895 -- and the back end would get the wrong value.
3897 if Is_Enumeration_Type (Ityp)
3898 and then Present (Enum_Pos_To_Rep (Base_Type (Ityp)))
3903 Xnum := Expr_Value (First (Expressions (N)));
3907 Make_Attribute_Reference (Loc,
3908 Prefix => New_Occurrence_Of (Typ, Loc),
3909 Attribute_Name => Name_Max,
3910 Expressions => New_List
3911 (Make_Integer_Literal (Loc, 0),
3915 Make_Op_Subtract (Loc,
3917 Make_Attribute_Reference (Loc,
3918 Prefix => New_Occurrence_Of (Ityp, Loc),
3919 Attribute_Name => Name_Pos,
3921 Expressions => New_List (
3922 Make_Attribute_Reference (Loc,
3923 Prefix => Duplicate_Subexpr (Pref),
3924 Attribute_Name => Name_Last,
3925 Expressions => New_List (
3926 Make_Integer_Literal (Loc, Xnum))))),
3929 Make_Attribute_Reference (Loc,
3930 Prefix => New_Occurrence_Of (Ityp, Loc),
3931 Attribute_Name => Name_Pos,
3933 Expressions => New_List (
3934 Make_Attribute_Reference (Loc,
3936 Duplicate_Subexpr_No_Checks (Pref),
3937 Attribute_Name => Name_First,
3938 Expressions => New_List (
3939 Make_Integer_Literal (Loc, Xnum)))))),
3941 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
3943 Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
3946 -- If the prefix type is a constrained packed array type which
3947 -- already has a Packed_Array_Impl_Type representation defined,
3948 -- then replace this attribute with a reference to 'Range_Length
3949 -- of the appropriate index subtype (since otherwise the
3950 -- back end will try to give us the value of 'Length for
3951 -- this implementation type).s
3953 elsif Is_Constrained (Ptyp) then
3955 Make_Attribute_Reference (Loc,
3956 Attribute_Name => Name_Range_Length,
3957 Prefix => New_Occurrence_Of (Ityp, Loc)));
3958 Analyze_And_Resolve (N, Typ);
3963 elsif Is_Access_Type (Ptyp) then
3964 Apply_Access_Check (N);
3966 -- If the designated type is a packed array type, then we convert
3967 -- the reference to:
3970 -- xtyp'Pos (Pref'Last (Expr)) -
3971 -- xtyp'Pos (Pref'First (Expr)));
3973 -- This is a bit complex, but it is the easiest thing to do that
3974 -- works in all cases including enum types with holes xtyp here
3975 -- is the appropriate index type.
3978 Dtyp : constant Entity_Id := Designated_Type (Ptyp);
3982 if Is_Array_Type (Dtyp) and then Is_Packed (Dtyp) then
3983 Xtyp := Get_Index_Subtype (N);
3986 Make_Attribute_Reference (Loc,
3987 Prefix => New_Occurrence_Of (Typ, Loc),
3988 Attribute_Name => Name_Max,
3989 Expressions => New_List (
3990 Make_Integer_Literal (Loc, 0),
3993 Make_Integer_Literal (Loc, 1),
3994 Make_Op_Subtract (Loc,
3996 Make_Attribute_Reference (Loc,
3997 Prefix => New_Occurrence_Of (Xtyp, Loc),
3998 Attribute_Name => Name_Pos,
3999 Expressions => New_List (
4000 Make_Attribute_Reference (Loc,
4001 Prefix => Duplicate_Subexpr (Pref),
4002 Attribute_Name => Name_Last,
4004 New_Copy_List (Exprs)))),
4007 Make_Attribute_Reference (Loc,
4008 Prefix => New_Occurrence_Of (Xtyp, Loc),
4009 Attribute_Name => Name_Pos,
4010 Expressions => New_List (
4011 Make_Attribute_Reference (Loc,
4013 Duplicate_Subexpr_No_Checks (Pref),
4014 Attribute_Name => Name_First,
4016 New_Copy_List (Exprs)))))))));
4018 Analyze_And_Resolve (N, Typ);
4022 -- Otherwise leave it to the back end
4025 Apply_Universal_Integer_Attribute_Checks (N);
4029 -- Attribute Loop_Entry is replaced with a reference to a constant value
4030 -- which captures the prefix at the entry point of the related loop. The
4031 -- loop itself may be transformed into a conditional block.
4033 when Attribute_Loop_Entry =>
4034 Expand_Loop_Entry_Attribute (N);
4040 -- Transforms 'Machine into a call to the floating-point attribute
4041 -- function Machine in Fat_xxx (where xxx is the root type).
4042 -- Expansion is avoided for cases the back end can handle directly.
4044 when Attribute_Machine =>
4045 if not Is_Inline_Floating_Point_Attribute (N) then
4046 Expand_Fpt_Attribute_R (N);
4049 ----------------------
4050 -- Machine_Rounding --
4051 ----------------------
4053 -- Transforms 'Machine_Rounding into a call to the floating-point
4054 -- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
4055 -- type). Expansion is avoided for cases the back end can handle
4058 when Attribute_Machine_Rounding =>
4059 if not Is_Inline_Floating_Point_Attribute (N) then
4060 Expand_Fpt_Attribute_R (N);
4067 -- Machine_Size is equivalent to Object_Size, so transform it into
4068 -- Object_Size and that way the back end never sees Machine_Size.
4070 when Attribute_Machine_Size =>
4072 Make_Attribute_Reference (Loc,
4073 Prefix => Prefix (N),
4074 Attribute_Name => Name_Object_Size));
4076 Analyze_And_Resolve (N, Typ);
4082 -- The only case that can get this far is the dynamic case of the old
4083 -- Ada 83 Mantissa attribute for the fixed-point case. For this case,
4090 -- ityp (System.Mantissa.Mantissa_Value
4091 -- (Integer'Integer_Value (typ'First),
4092 -- Integer'Integer_Value (typ'Last)));
4094 when Attribute_Mantissa => Mantissa : begin
4097 Make_Function_Call (Loc,
4098 Name => New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc),
4100 Parameter_Associations => New_List (
4102 Make_Attribute_Reference (Loc,
4103 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
4104 Attribute_Name => Name_Integer_Value,
4105 Expressions => New_List (
4107 Make_Attribute_Reference (Loc,
4108 Prefix => New_Occurrence_Of (Ptyp, Loc),
4109 Attribute_Name => Name_First))),
4111 Make_Attribute_Reference (Loc,
4112 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
4113 Attribute_Name => Name_Integer_Value,
4114 Expressions => New_List (
4116 Make_Attribute_Reference (Loc,
4117 Prefix => New_Occurrence_Of (Ptyp, Loc),
4118 Attribute_Name => Name_Last)))))));
4120 Analyze_And_Resolve (N, Typ);
4127 when Attribute_Max =>
4128 Expand_Min_Max_Attribute (N);
4130 ----------------------------------
4131 -- Max_Size_In_Storage_Elements --
4132 ----------------------------------
4134 when Attribute_Max_Size_In_Storage_Elements => declare
4135 Typ : constant Entity_Id := Etype (N);
4138 Conversion_Added : Boolean := False;
4139 -- A flag which tracks whether the original attribute has been
4140 -- wrapped inside a type conversion.
4143 -- If the prefix is X'Class, we transform it into a direct reference
4144 -- to the class-wide type, because the back end must not see a 'Class
4145 -- reference. See also 'Size.
4147 if Is_Entity_Name (Pref)
4148 and then Is_Class_Wide_Type (Entity (Pref))
4150 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
4154 Apply_Universal_Integer_Attribute_Checks (N);
4156 -- The universal integer check may sometimes add a type conversion,
4157 -- retrieve the original attribute reference from the expression.
4161 if Nkind (Attr) = N_Type_Conversion then
4162 Attr := Expression (Attr);
4163 Conversion_Added := True;
4166 pragma Assert (Nkind (Attr) = N_Attribute_Reference);
4168 -- Heap-allocated controlled objects contain two extra pointers which
4169 -- are not part of the actual type. Transform the attribute reference
4170 -- into a runtime expression to add the size of the hidden header.
4172 if Needs_Finalization (Ptyp)
4173 and then not Header_Size_Added (Attr)
4175 Set_Header_Size_Added (Attr);
4178 -- P'Max_Size_In_Storage_Elements +
4179 -- Universal_Integer
4180 -- (Header_Size_With_Padding (Ptyp'Alignment))
4184 Left_Opnd => Relocate_Node (Attr),
4186 Convert_To (Universal_Integer,
4187 Make_Function_Call (Loc,
4190 (RTE (RE_Header_Size_With_Padding), Loc),
4192 Parameter_Associations => New_List (
4193 Make_Attribute_Reference (Loc,
4195 New_Occurrence_Of (Ptyp, Loc),
4196 Attribute_Name => Name_Alignment))))));
4198 -- Add a conversion to the target type
4200 if not Conversion_Added then
4202 Make_Type_Conversion (Loc,
4203 Subtype_Mark => New_Occurrence_Of (Typ, Loc),
4204 Expression => Relocate_Node (Attr)));
4212 --------------------
4213 -- Mechanism_Code --
4214 --------------------
4216 when Attribute_Mechanism_Code =>
4218 -- We must replace the prefix i the renamed case
4220 if Is_Entity_Name (Pref)
4221 and then Present (Alias (Entity (Pref)))
4223 Set_Renamed_Subprogram (Pref, Alias (Entity (Pref)));
4230 when Attribute_Min =>
4231 Expand_Min_Max_Attribute (N);
4237 when Attribute_Mod => Mod_Case : declare
4238 Arg : constant Node_Id := Relocate_Node (First (Exprs));
4239 Hi : constant Node_Id := Type_High_Bound (Etype (Arg));
4240 Modv : constant Uint := Modulus (Btyp);
4244 -- This is not so simple. The issue is what type to use for the
4245 -- computation of the modular value.
4247 -- The easy case is when the modulus value is within the bounds
4248 -- of the signed integer type of the argument. In this case we can
4249 -- just do the computation in that signed integer type, and then
4250 -- do an ordinary conversion to the target type.
4252 if Modv <= Expr_Value (Hi) then
4257 Right_Opnd => Make_Integer_Literal (Loc, Modv))));
4259 -- Here we know that the modulus is larger than type'Last of the
4260 -- integer type. There are two cases to consider:
4262 -- a) The integer value is non-negative. In this case, it is
4263 -- returned as the result (since it is less than the modulus).
4265 -- b) The integer value is negative. In this case, we know that the
4266 -- result is modulus + value, where the value might be as small as
4267 -- -modulus. The trouble is what type do we use to do the subtract.
4268 -- No type will do, since modulus can be as big as 2**64, and no
4269 -- integer type accommodates this value. Let's do bit of algebra
4272 -- = modulus - (-value)
4273 -- = (modulus - 1) - (-value - 1)
4275 -- Now modulus - 1 is certainly in range of the modular type.
4276 -- -value is in the range 1 .. modulus, so -value -1 is in the
4277 -- range 0 .. modulus-1 which is in range of the modular type.
4278 -- Furthermore, (-value - 1) can be expressed as -(value + 1)
4279 -- which we can compute using the integer base type.
4281 -- Once this is done we analyze the if expression without range
4282 -- checks, because we know everything is in range, and we want
4283 -- to prevent spurious warnings on either branch.
4287 Make_If_Expression (Loc,
4288 Expressions => New_List (
4290 Left_Opnd => Duplicate_Subexpr (Arg),
4291 Right_Opnd => Make_Integer_Literal (Loc, 0)),
4294 Duplicate_Subexpr_No_Checks (Arg)),
4296 Make_Op_Subtract (Loc,
4298 Make_Integer_Literal (Loc,
4299 Intval => Modv - 1),
4305 Left_Opnd => Duplicate_Subexpr_No_Checks (Arg),
4307 Make_Integer_Literal (Loc,
4308 Intval => 1))))))));
4312 Analyze_And_Resolve (N, Btyp, Suppress => All_Checks);
4319 -- Transforms 'Model into a call to the floating-point attribute
4320 -- function Model in Fat_xxx (where xxx is the root type).
4321 -- Expansion is avoided for cases the back end can handle directly.
4323 when Attribute_Model =>
4324 if not Is_Inline_Floating_Point_Attribute (N) then
4325 Expand_Fpt_Attribute_R (N);
4332 -- The processing for Object_Size shares the processing for Size
4338 when Attribute_Old => Old : declare
4339 Typ : constant Entity_Id := Etype (N);
4340 CW_Temp : Entity_Id;
4346 -- Climb the parent chain looking for subprogram _Postconditions
4349 while Present (Subp) loop
4350 exit when Nkind (Subp) = N_Subprogram_Body
4351 and then Chars (Defining_Entity (Subp)) = Name_uPostconditions;
4353 -- If assertions are disabled, no need to create the declaration
4354 -- that preserves the value. The postcondition pragma in which
4355 -- 'Old appears will be checked or disabled according to the
4356 -- current policy in effect.
4358 if Nkind (Subp) = N_Pragma and then not Is_Checked (Subp) then
4362 Subp := Parent (Subp);
4365 -- 'Old can only appear in a postcondition, the generated body of
4366 -- _Postconditions must be in the tree.
4368 pragma Assert (Present (Subp));
4370 Temp := Make_Temporary (Loc, 'T', Pref);
4372 -- Set the entity kind now in order to mark the temporary as a
4373 -- handler of attribute 'Old's prefix.
4375 Set_Ekind (Temp, E_Constant);
4376 Set_Stores_Attribute_Old_Prefix (Temp);
4378 -- Push the scope of the related subprogram where _Postcondition
4379 -- resides as this ensures that the object will be analyzed in the
4382 Push_Scope (Scope (Defining_Entity (Subp)));
4384 -- Preserve the tag of the prefix by offering a specific view of the
4385 -- class-wide version of the prefix.
4387 if Is_Tagged_Type (Typ) then
4390 -- CW_Temp : constant Typ'Class := Typ'Class (Pref);
4392 CW_Temp := Make_Temporary (Loc, 'T');
4393 CW_Typ := Class_Wide_Type (Typ);
4395 Insert_Before_And_Analyze (Subp,
4396 Make_Object_Declaration (Loc,
4397 Defining_Identifier => CW_Temp,
4398 Constant_Present => True,
4399 Object_Definition => New_Occurrence_Of (CW_Typ, Loc),
4401 Convert_To (CW_Typ, Relocate_Node (Pref))));
4404 -- Temp : Typ renames Typ (CW_Temp);
4406 Insert_Before_And_Analyze (Subp,
4407 Make_Object_Renaming_Declaration (Loc,
4408 Defining_Identifier => Temp,
4409 Subtype_Mark => New_Occurrence_Of (Typ, Loc),
4411 Convert_To (Typ, New_Occurrence_Of (CW_Temp, Loc))));
4417 -- Temp : constant Typ := Pref;
4419 Insert_Before_And_Analyze (Subp,
4420 Make_Object_Declaration (Loc,
4421 Defining_Identifier => Temp,
4422 Constant_Present => True,
4423 Object_Definition => New_Occurrence_Of (Typ, Loc),
4424 Expression => Relocate_Node (Pref)));
4429 -- Ensure that the prefix of attribute 'Old is valid. The check must
4430 -- be inserted after the expansion of the attribute has taken place
4431 -- to reflect the new placement of the prefix.
4433 if Validity_Checks_On and then Validity_Check_Operands then
4434 Ensure_Valid (Pref);
4437 Rewrite (N, New_Occurrence_Of (Temp, Loc));
4440 ----------------------
4441 -- Overlaps_Storage --
4442 ----------------------
4444 when Attribute_Overlaps_Storage => Overlaps_Storage : declare
4445 Loc : constant Source_Ptr := Sloc (N);
4447 X : constant Node_Id := Prefix (N);
4448 Y : constant Node_Id := First (Expressions (N));
4451 X_Addr, Y_Addr : Node_Id;
4452 -- the expressions for their integer addresses
4454 X_Size, Y_Size : Node_Id;
4455 -- the expressions for their sizes
4460 -- Attribute expands into:
4462 -- if X'Address < Y'address then
4463 -- (X'address + X'Size - 1) >= Y'address
4465 -- (Y'address + Y'size - 1) >= X'Address
4468 -- with the proper address operations. We convert addresses to
4469 -- integer addresses to use predefined arithmetic. The size is
4470 -- expressed in storage units.
4473 Unchecked_Convert_To (RTE (RE_Integer_Address),
4474 Make_Attribute_Reference (Loc,
4475 Attribute_Name => Name_Address,
4476 Prefix => New_Copy_Tree (X)));
4479 Unchecked_Convert_To (RTE (RE_Integer_Address),
4480 Make_Attribute_Reference (Loc,
4481 Attribute_Name => Name_Address,
4482 Prefix => New_Copy_Tree (Y)));
4485 Make_Op_Divide (Loc,
4487 Make_Attribute_Reference (Loc,
4488 Attribute_Name => Name_Size,
4489 Prefix => New_Copy_Tree (X)),
4491 Make_Integer_Literal (Loc, System_Storage_Unit));
4494 Make_Op_Divide (Loc,
4496 Make_Attribute_Reference (Loc,
4497 Attribute_Name => Name_Size,
4498 Prefix => New_Copy_Tree (Y)),
4500 Make_Integer_Literal (Loc, System_Storage_Unit));
4504 Left_Opnd => X_Addr,
4505 Right_Opnd => Y_Addr);
4508 Make_If_Expression (Loc,
4515 Left_Opnd => X_Addr,
4517 Make_Op_Subtract (Loc,
4518 Left_Opnd => X_Size,
4519 Right_Opnd => Make_Integer_Literal (Loc, 1))),
4520 Right_Opnd => Y_Addr),
4524 Left_Opnd => Y_Addr,
4526 Make_Op_Subtract (Loc,
4527 Left_Opnd => Y_Size,
4528 Right_Opnd => Make_Integer_Literal (Loc, 1))),
4529 Right_Opnd => X_Addr))));
4531 Analyze_And_Resolve (N, Standard_Boolean);
4532 end Overlaps_Storage;
4538 when Attribute_Output => Output : declare
4539 P_Type : constant Entity_Id := Entity (Pref);
4540 U_Type : constant Entity_Id := Underlying_Type (P_Type);
4548 -- If no underlying type, we have an error that will be diagnosed
4549 -- elsewhere, so here we just completely ignore the expansion.
4555 -- Stream operations can appear in user code even if the restriction
4556 -- No_Streams is active (for example, when instantiating a predefined
4557 -- container). In that case rewrite the attribute as a Raise to
4558 -- prevent any run-time use.
4560 if Restriction_Active (No_Streams) then
4562 Make_Raise_Program_Error (Sloc (N),
4563 Reason => PE_Stream_Operation_Not_Allowed));
4564 Set_Etype (N, Standard_Void_Type);
4568 -- If TSS for Output is present, just call it
4570 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output);
4572 if Present (Pname) then
4576 -- If there is a Stream_Convert pragma, use it, we rewrite
4578 -- sourcetyp'Output (stream, Item)
4582 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
4584 -- where strmwrite is the given Write function that converts an
4585 -- argument of type sourcetyp or a type acctyp, from which it is
4586 -- derived to type strmtyp. The conversion to acttyp is required
4587 -- for the derived case.
4589 Prag := Get_Stream_Convert_Pragma (P_Type);
4591 if Present (Prag) then
4593 Next (Next (First (Pragma_Argument_Associations (Prag))));
4594 Wfunc := Entity (Expression (Arg3));
4597 Make_Attribute_Reference (Loc,
4598 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
4599 Attribute_Name => Name_Output,
4600 Expressions => New_List (
4601 Relocate_Node (First (Exprs)),
4602 Make_Function_Call (Loc,
4603 Name => New_Occurrence_Of (Wfunc, Loc),
4604 Parameter_Associations => New_List (
4605 OK_Convert_To (Etype (First_Formal (Wfunc)),
4606 Relocate_Node (Next (First (Exprs)))))))));
4611 -- For elementary types, we call the W_xxx routine directly. Note
4612 -- that the effect of Write and Output is identical for the case
4613 -- of an elementary type (there are no discriminants or bounds).
4615 elsif Is_Elementary_Type (U_Type) then
4617 -- A special case arises if we have a defined _Write routine,
4618 -- since in this case we are required to call this routine.
4620 if Present (TSS (Base_Type (U_Type), TSS_Stream_Write)) then
4621 Build_Record_Or_Elementary_Output_Procedure
4622 (Loc, U_Type, Decl, Pname);
4623 Insert_Action (N, Decl);
4625 -- For normal cases, we call the W_xxx routine directly
4628 Rewrite (N, Build_Elementary_Write_Call (N));
4635 elsif Is_Array_Type (U_Type) then
4636 Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname);
4637 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
4639 -- Class-wide case, first output external tag, then dispatch
4640 -- to the appropriate primitive Output function (RM 13.13.2(31)).
4642 elsif Is_Class_Wide_Type (P_Type) then
4644 -- No need to do anything else compiling under restriction
4645 -- No_Dispatching_Calls. During the semantic analysis we
4646 -- already notified such violation.
4648 if Restriction_Active (No_Dispatching_Calls) then
4653 Strm : constant Node_Id := First (Exprs);
4654 Item : constant Node_Id := Next (Strm);
4657 -- Ada 2005 (AI-344): Check that the accessibility level
4658 -- of the type of the output object is not deeper than
4659 -- that of the attribute's prefix type.
4661 -- if Get_Access_Level (Item'Tag)
4662 -- /= Get_Access_Level (P_Type'Tag)
4667 -- String'Output (Strm, External_Tag (Item'Tag));
4669 -- We cannot figure out a practical way to implement this
4670 -- accessibility check on virtual machines, so we omit it.
4672 if Ada_Version >= Ada_2005
4673 and then Tagged_Type_Expansion
4676 Make_Implicit_If_Statement (N,
4680 Build_Get_Access_Level (Loc,
4681 Make_Attribute_Reference (Loc,
4684 Duplicate_Subexpr (Item,
4686 Attribute_Name => Name_Tag)),
4689 Make_Integer_Literal (Loc,
4690 Type_Access_Level (P_Type))),
4693 New_List (Make_Raise_Statement (Loc,
4695 RTE (RE_Tag_Error), Loc)))));
4699 Make_Attribute_Reference (Loc,
4700 Prefix => New_Occurrence_Of (Standard_String, Loc),
4701 Attribute_Name => Name_Output,
4702 Expressions => New_List (
4703 Relocate_Node (Duplicate_Subexpr (Strm)),
4704 Make_Function_Call (Loc,
4706 New_Occurrence_Of (RTE (RE_External_Tag), Loc),
4707 Parameter_Associations => New_List (
4708 Make_Attribute_Reference (Loc,
4711 (Duplicate_Subexpr (Item, Name_Req => True)),
4712 Attribute_Name => Name_Tag))))));
4715 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
4717 -- Tagged type case, use the primitive Output function
4719 elsif Is_Tagged_Type (U_Type) then
4720 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
4722 -- All other record type cases, including protected records.
4723 -- The latter only arise for expander generated code for
4724 -- handling shared passive partition access.
4728 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
4730 -- Ada 2005 (AI-216): Program_Error is raised when executing
4731 -- the default implementation of the Output attribute of an
4732 -- unchecked union type if the type lacks default discriminant
4735 if Is_Unchecked_Union (Base_Type (U_Type))
4736 and then No (Discriminant_Constraint (U_Type))
4739 Make_Raise_Program_Error (Loc,
4740 Reason => PE_Unchecked_Union_Restriction));
4745 Build_Record_Or_Elementary_Output_Procedure
4746 (Loc, Base_Type (U_Type), Decl, Pname);
4747 Insert_Action (N, Decl);
4751 -- If we fall through, Pname is the name of the procedure to call
4753 Rewrite_Stream_Proc_Call (Pname);
4760 -- For enumeration types with a standard representation, Pos is
4761 -- handled by the back end.
4763 -- For enumeration types, with a non-standard representation we generate
4764 -- a call to the _Rep_To_Pos function created when the type was frozen.
4765 -- The call has the form
4767 -- _rep_to_pos (expr, flag)
4769 -- The parameter flag is True if range checks are enabled, causing
4770 -- Program_Error to be raised if the expression has an invalid
4771 -- representation, and False if range checks are suppressed.
4773 -- For integer types, Pos is equivalent to a simple integer
4774 -- conversion and we rewrite it as such
4776 when Attribute_Pos => Pos :
4778 Etyp : Entity_Id := Base_Type (Entity (Pref));
4781 -- Deal with zero/non-zero boolean values
4783 if Is_Boolean_Type (Etyp) then
4784 Adjust_Condition (First (Exprs));
4785 Etyp := Standard_Boolean;
4786 Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc));
4789 -- Case of enumeration type
4791 if Is_Enumeration_Type (Etyp) then
4793 -- Non-standard enumeration type (generate call)
4795 if Present (Enum_Pos_To_Rep (Etyp)) then
4796 Append_To (Exprs, Rep_To_Pos_Flag (Etyp, Loc));
4799 Make_Function_Call (Loc,
4801 New_Occurrence_Of (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4802 Parameter_Associations => Exprs)));
4804 Analyze_And_Resolve (N, Typ);
4806 -- Standard enumeration type (do universal integer check)
4809 Apply_Universal_Integer_Attribute_Checks (N);
4812 -- Deal with integer types (replace by conversion)
4814 elsif Is_Integer_Type (Etyp) then
4815 Rewrite (N, Convert_To (Typ, First (Exprs)));
4816 Analyze_And_Resolve (N, Typ);
4825 -- We compute this if a component clause was present, otherwise we leave
4826 -- the computation up to the back end, since we don't know what layout
4829 when Attribute_Position => Position_Attr :
4831 CE : constant Entity_Id := Entity (Selector_Name (Pref));
4834 if Present (Component_Clause (CE)) then
4836 -- In Ada 2005 (or later) if we have the non-default bit order,
4837 -- then we return the original value as given in the component
4838 -- clause (RM 2005 13.5.2(2/2)).
4840 if Ada_Version >= Ada_2005
4841 and then Reverse_Bit_Order (Scope (CE))
4844 Make_Integer_Literal (Loc,
4845 Intval => Expr_Value (Position (Component_Clause (CE)))));
4847 -- Otherwise (Ada 83 or 95, or default bit order specified in
4848 -- later Ada version), return the normalized value.
4852 Make_Integer_Literal (Loc,
4853 Intval => Component_Bit_Offset (CE) / System_Storage_Unit));
4856 Analyze_And_Resolve (N, Typ);
4858 -- If back end is doing things, just apply universal integer checks
4861 Apply_Universal_Integer_Attribute_Checks (N);
4869 -- 1. Deal with enumeration types with holes.
4870 -- 2. For floating-point, generate call to attribute function.
4871 -- 3. For other cases, deal with constraint checking.
4873 when Attribute_Pred => Pred :
4875 Etyp : constant Entity_Id := Base_Type (Ptyp);
4879 -- For enumeration types with non-standard representations, we
4880 -- expand typ'Pred (x) into
4882 -- Pos_To_Rep (Rep_To_Pos (x) - 1)
4884 -- If the representation is contiguous, we compute instead
4885 -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations.
4886 -- The conversion function Enum_Pos_To_Rep is defined on the
4887 -- base type, not the subtype, so we have to use the base type
4888 -- explicitly for this and other enumeration attributes.
4890 if Is_Enumeration_Type (Ptyp)
4891 and then Present (Enum_Pos_To_Rep (Etyp))
4893 if Has_Contiguous_Rep (Etyp) then
4895 Unchecked_Convert_To (Ptyp,
4898 Make_Integer_Literal (Loc,
4899 Enumeration_Rep (First_Literal (Ptyp))),
4901 Make_Function_Call (Loc,
4904 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4906 Parameter_Associations =>
4908 Unchecked_Convert_To (Ptyp,
4909 Make_Op_Subtract (Loc,
4911 Unchecked_Convert_To (Standard_Integer,
4912 Relocate_Node (First (Exprs))),
4914 Make_Integer_Literal (Loc, 1))),
4915 Rep_To_Pos_Flag (Ptyp, Loc))))));
4918 -- Add Boolean parameter True, to request program errror if
4919 -- we have a bad representation on our hands. If checks are
4920 -- suppressed, then add False instead
4922 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
4924 Make_Indexed_Component (Loc,
4927 (Enum_Pos_To_Rep (Etyp), Loc),
4928 Expressions => New_List (
4929 Make_Op_Subtract (Loc,
4931 Make_Function_Call (Loc,
4934 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4935 Parameter_Associations => Exprs),
4936 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
4939 Analyze_And_Resolve (N, Typ);
4941 -- For floating-point, we transform 'Pred into a call to the Pred
4942 -- floating-point attribute function in Fat_xxx (xxx is root type).
4943 -- Note that this function takes care of the overflow case.
4945 elsif Is_Floating_Point_Type (Ptyp) then
4946 Expand_Fpt_Attribute_R (N);
4947 Analyze_And_Resolve (N, Typ);
4949 -- For modular types, nothing to do (no overflow, since wraps)
4951 elsif Is_Modular_Integer_Type (Ptyp) then
4954 -- For other types, if argument is marked as needing a range check or
4955 -- overflow checking is enabled, we must generate a check.
4957 elsif not Overflow_Checks_Suppressed (Ptyp)
4958 or else Do_Range_Check (First (Exprs))
4960 Set_Do_Range_Check (First (Exprs), False);
4961 Expand_Pred_Succ_Attribute (N);
4969 -- Ada 2005 (AI-327): Dynamic ceiling priorities
4971 -- We rewrite X'Priority as the following run-time call:
4973 -- Get_Ceiling (X._Object)
4975 -- Note that although X'Priority is notionally an object, it is quite
4976 -- deliberately not defined as an aliased object in the RM. This means
4977 -- that it works fine to rewrite it as a call, without having to worry
4978 -- about complications that would other arise from X'Priority'Access,
4979 -- which is illegal, because of the lack of aliasing.
4981 when Attribute_Priority =>
4984 Conctyp : Entity_Id;
4985 Object_Parm : Node_Id;
4987 RT_Subprg_Name : Node_Id;
4990 -- Look for the enclosing concurrent type
4992 Conctyp := Current_Scope;
4993 while not Is_Concurrent_Type (Conctyp) loop
4994 Conctyp := Scope (Conctyp);
4997 pragma Assert (Is_Protected_Type (Conctyp));
4999 -- Generate the actual of the call
5001 Subprg := Current_Scope;
5002 while not Present (Protected_Body_Subprogram (Subprg)) loop
5003 Subprg := Scope (Subprg);
5006 -- Use of 'Priority inside protected entries and barriers (in
5007 -- both cases the type of the first formal of their expanded
5008 -- subprogram is Address)
5010 if Etype (First_Entity (Protected_Body_Subprogram (Subprg)))
5014 New_Itype : Entity_Id;
5017 -- In the expansion of protected entries the type of the
5018 -- first formal of the Protected_Body_Subprogram is an
5019 -- Address. In order to reference the _object component
5022 -- type T is access p__ptTV;
5025 New_Itype := Create_Itype (E_Access_Type, N);
5026 Set_Etype (New_Itype, New_Itype);
5027 Set_Directly_Designated_Type (New_Itype,
5028 Corresponding_Record_Type (Conctyp));
5029 Freeze_Itype (New_Itype, N);
5032 -- T!(O)._object'unchecked_access
5035 Make_Attribute_Reference (Loc,
5037 Make_Selected_Component (Loc,
5039 Unchecked_Convert_To (New_Itype,
5042 (Protected_Body_Subprogram (Subprg)),
5045 Make_Identifier (Loc, Name_uObject)),
5046 Attribute_Name => Name_Unchecked_Access);
5049 -- Use of 'Priority inside a protected subprogram
5053 Make_Attribute_Reference (Loc,
5055 Make_Selected_Component (Loc,
5056 Prefix => New_Occurrence_Of
5058 (Protected_Body_Subprogram (Subprg)),
5060 Selector_Name => Make_Identifier (Loc, Name_uObject)),
5061 Attribute_Name => Name_Unchecked_Access);
5064 -- Select the appropriate run-time subprogram
5066 if Number_Entries (Conctyp) = 0 then
5068 New_Occurrence_Of (RTE (RE_Get_Ceiling), Loc);
5071 New_Occurrence_Of (RTE (RO_PE_Get_Ceiling), Loc);
5075 Make_Function_Call (Loc,
5076 Name => RT_Subprg_Name,
5077 Parameter_Associations => New_List (Object_Parm));
5081 -- Avoid the generation of extra checks on the pointer to the
5082 -- protected object.
5084 Analyze_And_Resolve (N, Typ, Suppress => Access_Check);
5091 when Attribute_Range_Length => Range_Length : begin
5093 -- The only special processing required is for the case where
5094 -- Range_Length is applied to an enumeration type with holes.
5095 -- In this case we transform
5101 -- X'Pos (X'Last) - X'Pos (X'First) + 1
5103 -- So that the result reflects the proper Pos values instead
5104 -- of the underlying representations.
5106 if Is_Enumeration_Type (Ptyp)
5107 and then Has_Non_Standard_Rep (Ptyp)
5112 Make_Op_Subtract (Loc,
5114 Make_Attribute_Reference (Loc,
5115 Attribute_Name => Name_Pos,
5116 Prefix => New_Occurrence_Of (Ptyp, Loc),
5117 Expressions => New_List (
5118 Make_Attribute_Reference (Loc,
5119 Attribute_Name => Name_Last,
5120 Prefix => New_Occurrence_Of (Ptyp, Loc)))),
5123 Make_Attribute_Reference (Loc,
5124 Attribute_Name => Name_Pos,
5125 Prefix => New_Occurrence_Of (Ptyp, Loc),
5126 Expressions => New_List (
5127 Make_Attribute_Reference (Loc,
5128 Attribute_Name => Name_First,
5129 Prefix => New_Occurrence_Of (Ptyp, Loc))))),
5131 Right_Opnd => Make_Integer_Literal (Loc, 1)));
5133 Analyze_And_Resolve (N, Typ);
5135 -- For all other cases, the attribute is handled by the back end, but
5136 -- we need to deal with the case of the range check on a universal
5140 Apply_Universal_Integer_Attribute_Checks (N);
5148 when Attribute_Read => Read : declare
5149 P_Type : constant Entity_Id := Entity (Pref);
5150 B_Type : constant Entity_Id := Base_Type (P_Type);
5151 U_Type : constant Entity_Id := Underlying_Type (P_Type);
5161 -- If no underlying type, we have an error that will be diagnosed
5162 -- elsewhere, so here we just completely ignore the expansion.
5168 -- Stream operations can appear in user code even if the restriction
5169 -- No_Streams is active (for example, when instantiating a predefined
5170 -- container). In that case rewrite the attribute as a Raise to
5171 -- prevent any run-time use.
5173 if Restriction_Active (No_Streams) then
5175 Make_Raise_Program_Error (Sloc (N),
5176 Reason => PE_Stream_Operation_Not_Allowed));
5177 Set_Etype (N, B_Type);
5181 -- The simple case, if there is a TSS for Read, just call it
5183 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Read);
5185 if Present (Pname) then
5189 -- If there is a Stream_Convert pragma, use it, we rewrite
5191 -- sourcetyp'Read (stream, Item)
5195 -- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
5197 -- where strmread is the given Read function that converts an
5198 -- argument of type strmtyp to type sourcetyp or a type from which
5199 -- it is derived. The conversion to sourcetyp is required in the
5202 -- A special case arises if Item is a type conversion in which
5203 -- case, we have to expand to:
5205 -- Itemx := typex (strmread (strmtyp'Input (Stream)));
5207 -- where Itemx is the expression of the type conversion (i.e.
5208 -- the actual object), and typex is the type of Itemx.
5210 Prag := Get_Stream_Convert_Pragma (P_Type);
5212 if Present (Prag) then
5213 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
5214 Rfunc := Entity (Expression (Arg2));
5215 Lhs := Relocate_Node (Next (First (Exprs)));
5217 OK_Convert_To (B_Type,
5218 Make_Function_Call (Loc,
5219 Name => New_Occurrence_Of (Rfunc, Loc),
5220 Parameter_Associations => New_List (
5221 Make_Attribute_Reference (Loc,
5224 (Etype (First_Formal (Rfunc)), Loc),
5225 Attribute_Name => Name_Input,
5226 Expressions => New_List (
5227 Relocate_Node (First (Exprs)))))));
5229 if Nkind (Lhs) = N_Type_Conversion then
5230 Lhs := Expression (Lhs);
5231 Rhs := Convert_To (Etype (Lhs), Rhs);
5235 Make_Assignment_Statement (Loc,
5237 Expression => Rhs));
5238 Set_Assignment_OK (Lhs);
5242 -- For elementary types, we call the I_xxx routine using the first
5243 -- parameter and then assign the result into the second parameter.
5244 -- We set Assignment_OK to deal with the conversion case.
5246 elsif Is_Elementary_Type (U_Type) then
5252 Lhs := Relocate_Node (Next (First (Exprs)));
5253 Rhs := Build_Elementary_Input_Call (N);
5255 if Nkind (Lhs) = N_Type_Conversion then
5256 Lhs := Expression (Lhs);
5257 Rhs := Convert_To (Etype (Lhs), Rhs);
5260 Set_Assignment_OK (Lhs);
5263 Make_Assignment_Statement (Loc,
5265 Expression => Rhs));
5273 elsif Is_Array_Type (U_Type) then
5274 Build_Array_Read_Procedure (N, U_Type, Decl, Pname);
5275 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
5277 -- Tagged type case, use the primitive Read function. Note that
5278 -- this will dispatch in the class-wide case which is what we want
5280 elsif Is_Tagged_Type (U_Type) then
5281 Pname := Find_Prim_Op (U_Type, TSS_Stream_Read);
5283 -- All other record type cases, including protected records. The
5284 -- latter only arise for expander generated code for handling
5285 -- shared passive partition access.
5289 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
5291 -- Ada 2005 (AI-216): Program_Error is raised when executing
5292 -- the default implementation of the Read attribute of an
5293 -- Unchecked_Union type.
5295 if Is_Unchecked_Union (Base_Type (U_Type)) then
5297 Make_Raise_Program_Error (Loc,
5298 Reason => PE_Unchecked_Union_Restriction));
5301 if Has_Discriminants (U_Type)
5303 (Discriminant_Default_Value (First_Discriminant (U_Type)))
5305 Build_Mutable_Record_Read_Procedure
5306 (Loc, Full_Base (U_Type), Decl, Pname);
5308 Build_Record_Read_Procedure
5309 (Loc, Full_Base (U_Type), Decl, Pname);
5312 -- Suppress checks, uninitialized or otherwise invalid
5313 -- data does not cause constraint errors to be raised for
5314 -- a complete record read.
5316 Insert_Action (N, Decl, All_Checks);
5320 Rewrite_Stream_Proc_Call (Pname);
5327 -- Ref is identical to To_Address, see To_Address for processing
5333 -- Transforms 'Remainder into a call to the floating-point attribute
5334 -- function Remainder in Fat_xxx (where xxx is the root type)
5336 when Attribute_Remainder =>
5337 Expand_Fpt_Attribute_RR (N);
5343 -- Transform 'Result into reference to _Result formal. At the point
5344 -- where a legal 'Result attribute is expanded, we know that we are in
5345 -- the context of a _Postcondition function with a _Result parameter.
5347 when Attribute_Result =>
5348 Rewrite (N, Make_Identifier (Loc, Chars => Name_uResult));
5349 Analyze_And_Resolve (N, Typ);
5355 -- The handling of the Round attribute is quite delicate. The processing
5356 -- in Sem_Attr introduced a conversion to universal real, reflecting the
5357 -- semantics of Round, but we do not want anything to do with universal
5358 -- real at runtime, since this corresponds to using floating-point
5361 -- What we have now is that the Etype of the Round attribute correctly
5362 -- indicates the final result type. The operand of the Round is the
5363 -- conversion to universal real, described above, and the operand of
5364 -- this conversion is the actual operand of Round, which may be the
5365 -- special case of a fixed point multiplication or division (Etype =
5368 -- The exapander will expand first the operand of the conversion, then
5369 -- the conversion, and finally the round attribute itself, since we
5370 -- always work inside out. But we cannot simply process naively in this
5371 -- order. In the semantic world where universal fixed and real really
5372 -- exist and have infinite precision, there is no problem, but in the
5373 -- implementation world, where universal real is a floating-point type,
5374 -- we would get the wrong result.
5376 -- So the approach is as follows. First, when expanding a multiply or
5377 -- divide whose type is universal fixed, we do nothing at all, instead
5378 -- deferring the operation till later.
5380 -- The actual processing is done in Expand_N_Type_Conversion which
5381 -- handles the special case of Round by looking at its parent to see if
5382 -- it is a Round attribute, and if it is, handling the conversion (or
5383 -- its fixed multiply/divide child) in an appropriate manner.
5385 -- This means that by the time we get to expanding the Round attribute
5386 -- itself, the Round is nothing more than a type conversion (and will
5387 -- often be a null type conversion), so we just replace it with the
5388 -- appropriate conversion operation.
5390 when Attribute_Round =>
5392 Convert_To (Etype (N), Relocate_Node (First (Exprs))));
5393 Analyze_And_Resolve (N);
5399 -- Transforms 'Rounding into a call to the floating-point attribute
5400 -- function Rounding in Fat_xxx (where xxx is the root type)
5401 -- Expansion is avoided for cases the back end can handle directly.
5403 when Attribute_Rounding =>
5404 if not Is_Inline_Floating_Point_Attribute (N) then
5405 Expand_Fpt_Attribute_R (N);
5412 -- Transforms 'Scaling into a call to the floating-point attribute
5413 -- function Scaling in Fat_xxx (where xxx is the root type)
5415 when Attribute_Scaling =>
5416 Expand_Fpt_Attribute_RI (N);
5418 -------------------------
5419 -- Simple_Storage_Pool --
5420 -------------------------
5422 when Attribute_Simple_Storage_Pool =>
5424 Make_Type_Conversion (Loc,
5425 Subtype_Mark => New_Occurrence_Of (Etype (N), Loc),
5426 Expression => New_Occurrence_Of (Entity (N), Loc)));
5427 Analyze_And_Resolve (N, Typ);
5433 when Attribute_Size |
5434 Attribute_Object_Size |
5435 Attribute_Value_Size |
5436 Attribute_VADS_Size => Size :
5443 -- Processing for VADS_Size case. Note that this processing removes
5444 -- all traces of VADS_Size from the tree, and completes all required
5445 -- processing for VADS_Size by translating the attribute reference
5446 -- to an appropriate Size or Object_Size reference.
5448 if Id = Attribute_VADS_Size
5449 or else (Use_VADS_Size and then Id = Attribute_Size)
5451 -- If the size is specified, then we simply use the specified
5452 -- size. This applies to both types and objects. The size of an
5453 -- object can be specified in the following ways:
5455 -- An explicit size object is given for an object
5456 -- A component size is specified for an indexed component
5457 -- A component clause is specified for a selected component
5458 -- The object is a component of a packed composite object
5460 -- If the size is specified, then VADS_Size of an object
5462 if (Is_Entity_Name (Pref)
5463 and then Present (Size_Clause (Entity (Pref))))
5465 (Nkind (Pref) = N_Component_Clause
5466 and then (Present (Component_Clause
5467 (Entity (Selector_Name (Pref))))
5468 or else Is_Packed (Etype (Prefix (Pref)))))
5470 (Nkind (Pref) = N_Indexed_Component
5471 and then (Component_Size (Etype (Prefix (Pref))) /= 0
5472 or else Is_Packed (Etype (Prefix (Pref)))))
5474 Set_Attribute_Name (N, Name_Size);
5476 -- Otherwise if we have an object rather than a type, then the
5477 -- VADS_Size attribute applies to the type of the object, rather
5478 -- than the object itself. This is one of the respects in which
5479 -- VADS_Size differs from Size.
5482 if (not Is_Entity_Name (Pref)
5483 or else not Is_Type (Entity (Pref)))
5484 and then (Is_Scalar_Type (Ptyp) or else Is_Constrained (Ptyp))
5486 Rewrite (Pref, New_Occurrence_Of (Ptyp, Loc));
5489 -- For a scalar type for which no size was explicitly given,
5490 -- VADS_Size means Object_Size. This is the other respect in
5491 -- which VADS_Size differs from Size.
5493 if Is_Scalar_Type (Ptyp) and then No (Size_Clause (Ptyp)) then
5494 Set_Attribute_Name (N, Name_Object_Size);
5496 -- In all other cases, Size and VADS_Size are the sane
5499 Set_Attribute_Name (N, Name_Size);
5504 -- If the prefix is X'Class, we transform it into a direct reference
5505 -- to the class-wide type, because the back end must not see a 'Class
5508 if Is_Entity_Name (Pref)
5509 and then Is_Class_Wide_Type (Entity (Pref))
5511 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
5514 -- For X'Size applied to an object of a class-wide type, transform
5515 -- X'Size into a call to the primitive operation _Size applied to X.
5517 elsif Is_Class_Wide_Type (Ptyp) then
5519 -- No need to do anything else compiling under restriction
5520 -- No_Dispatching_Calls. During the semantic analysis we
5521 -- already noted this restriction violation.
5523 if Restriction_Active (No_Dispatching_Calls) then
5528 Make_Function_Call (Loc,
5529 Name => New_Occurrence_Of
5530 (Find_Prim_Op (Ptyp, Name_uSize), Loc),
5531 Parameter_Associations => New_List (Pref));
5533 if Typ /= Standard_Long_Long_Integer then
5535 -- The context is a specific integer type with which the
5536 -- original attribute was compatible. The function has a
5537 -- specific type as well, so to preserve the compatibility
5538 -- we must convert explicitly.
5540 New_Node := Convert_To (Typ, New_Node);
5543 Rewrite (N, New_Node);
5544 Analyze_And_Resolve (N, Typ);
5547 -- Case of known RM_Size of a type
5549 elsif (Id = Attribute_Size or else Id = Attribute_Value_Size)
5550 and then Is_Entity_Name (Pref)
5551 and then Is_Type (Entity (Pref))
5552 and then Known_Static_RM_Size (Entity (Pref))
5554 Siz := RM_Size (Entity (Pref));
5556 -- Case of known Esize of a type
5558 elsif Id = Attribute_Object_Size
5559 and then Is_Entity_Name (Pref)
5560 and then Is_Type (Entity (Pref))
5561 and then Known_Static_Esize (Entity (Pref))
5563 Siz := Esize (Entity (Pref));
5565 -- Case of known size of object
5567 elsif Id = Attribute_Size
5568 and then Is_Entity_Name (Pref)
5569 and then Is_Object (Entity (Pref))
5570 and then Known_Esize (Entity (Pref))
5571 and then Known_Static_Esize (Entity (Pref))
5573 Siz := Esize (Entity (Pref));
5575 -- For an array component, we can do Size in the front end
5576 -- if the component_size of the array is set.
5578 elsif Nkind (Pref) = N_Indexed_Component then
5579 Siz := Component_Size (Etype (Prefix (Pref)));
5581 -- For a record component, we can do Size in the front end if there
5582 -- is a component clause, or if the record is packed and the
5583 -- component's size is known at compile time.
5585 elsif Nkind (Pref) = N_Selected_Component then
5587 Rec : constant Entity_Id := Etype (Prefix (Pref));
5588 Comp : constant Entity_Id := Entity (Selector_Name (Pref));
5591 if Present (Component_Clause (Comp)) then
5592 Siz := Esize (Comp);
5594 elsif Is_Packed (Rec) then
5595 Siz := RM_Size (Ptyp);
5598 Apply_Universal_Integer_Attribute_Checks (N);
5603 -- All other cases are handled by the back end
5606 Apply_Universal_Integer_Attribute_Checks (N);
5608 -- If Size is applied to a formal parameter that is of a packed
5609 -- array subtype, then apply Size to the actual subtype.
5611 if Is_Entity_Name (Pref)
5612 and then Is_Formal (Entity (Pref))
5613 and then Is_Array_Type (Ptyp)
5614 and then Is_Packed (Ptyp)
5617 Make_Attribute_Reference (Loc,
5619 New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc),
5620 Attribute_Name => Name_Size));
5621 Analyze_And_Resolve (N, Typ);
5624 -- If Size applies to a dereference of an access to unconstrained
5625 -- packed array, the back end needs to see its unconstrained
5626 -- nominal type, but also a hint to the actual constrained type.
5628 if Nkind (Pref) = N_Explicit_Dereference
5629 and then Is_Array_Type (Ptyp)
5630 and then not Is_Constrained (Ptyp)
5631 and then Is_Packed (Ptyp)
5633 Set_Actual_Designated_Subtype (Pref,
5634 Get_Actual_Subtype (Pref));
5640 -- Common processing for record and array component case
5642 if Siz /= No_Uint and then Siz /= 0 then
5644 CS : constant Boolean := Comes_From_Source (N);
5647 Rewrite (N, Make_Integer_Literal (Loc, Siz));
5649 -- This integer literal is not a static expression. We do not
5650 -- call Analyze_And_Resolve here, because this would activate
5651 -- the circuit for deciding that a static value was out of
5652 -- range, and we don't want that.
5654 -- So just manually set the type, mark the expression as non-
5655 -- static, and then ensure that the result is checked properly
5656 -- if the attribute comes from source (if it was internally
5657 -- generated, we never need a constraint check).
5660 Set_Is_Static_Expression (N, False);
5663 Apply_Constraint_Check (N, Typ);
5673 when Attribute_Storage_Pool =>
5675 Make_Type_Conversion (Loc,
5676 Subtype_Mark => New_Occurrence_Of (Etype (N), Loc),
5677 Expression => New_Occurrence_Of (Entity (N), Loc)));
5678 Analyze_And_Resolve (N, Typ);
5684 when Attribute_Storage_Size => Storage_Size : declare
5685 Alloc_Op : Entity_Id := Empty;
5689 -- Access type case, always go to the root type
5691 -- The case of access types results in a value of zero for the case
5692 -- where no storage size attribute clause has been given. If a
5693 -- storage size has been given, then the attribute is converted
5694 -- to a reference to the variable used to hold this value.
5696 if Is_Access_Type (Ptyp) then
5697 if Present (Storage_Size_Variable (Root_Type (Ptyp))) then
5699 Make_Attribute_Reference (Loc,
5700 Prefix => New_Occurrence_Of (Typ, Loc),
5701 Attribute_Name => Name_Max,
5702 Expressions => New_List (
5703 Make_Integer_Literal (Loc, 0),
5706 (Storage_Size_Variable (Root_Type (Ptyp)), Loc)))));
5708 elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then
5710 -- If the access type is associated with a simple storage pool
5711 -- object, then attempt to locate the optional Storage_Size
5712 -- function of the simple storage pool type. If not found,
5713 -- then the result will default to zero.
5715 if Present (Get_Rep_Pragma (Root_Type (Ptyp),
5716 Name_Simple_Storage_Pool_Type))
5719 Pool_Type : constant Entity_Id :=
5720 Base_Type (Etype (Entity (N)));
5723 Alloc_Op := Get_Name_Entity_Id (Name_Storage_Size);
5724 while Present (Alloc_Op) loop
5725 if Scope (Alloc_Op) = Scope (Pool_Type)
5726 and then Present (First_Formal (Alloc_Op))
5727 and then Etype (First_Formal (Alloc_Op)) = Pool_Type
5732 Alloc_Op := Homonym (Alloc_Op);
5736 -- In the normal Storage_Pool case, retrieve the primitive
5737 -- function associated with the pool type.
5742 (Etype (Associated_Storage_Pool (Root_Type (Ptyp))),
5743 Attribute_Name (N));
5746 -- If Storage_Size wasn't found (can only occur in the simple
5747 -- storage pool case), then simply use zero for the result.
5749 if not Present (Alloc_Op) then
5750 Rewrite (N, Make_Integer_Literal (Loc, 0));
5752 -- Otherwise, rewrite the allocator as a call to pool type's
5753 -- Storage_Size function.
5758 Make_Function_Call (Loc,
5760 New_Occurrence_Of (Alloc_Op, Loc),
5762 Parameter_Associations => New_List (
5764 (Associated_Storage_Pool
5765 (Root_Type (Ptyp)), Loc)))));
5769 Rewrite (N, Make_Integer_Literal (Loc, 0));
5772 Analyze_And_Resolve (N, Typ);
5774 -- For tasks, we retrieve the size directly from the TCB. The
5775 -- size may depend on a discriminant of the type, and therefore
5776 -- can be a per-object expression, so type-level information is
5777 -- not sufficient in general. There are four cases to consider:
5779 -- a) If the attribute appears within a task body, the designated
5780 -- TCB is obtained by a call to Self.
5782 -- b) If the prefix of the attribute is the name of a task object,
5783 -- the designated TCB is the one stored in the corresponding record.
5785 -- c) If the prefix is a task type, the size is obtained from the
5786 -- size variable created for each task type
5788 -- d) If no Storage_Size was specified for the type, there is no
5789 -- size variable, and the value is a system-specific default.
5792 if In_Open_Scopes (Ptyp) then
5794 -- Storage_Size (Self)
5798 Make_Function_Call (Loc,
5800 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
5801 Parameter_Associations =>
5803 Make_Function_Call (Loc,
5805 New_Occurrence_Of (RTE (RE_Self), Loc))))));
5807 elsif not Is_Entity_Name (Pref)
5808 or else not Is_Type (Entity (Pref))
5810 -- Storage_Size (Rec (Obj).Size)
5814 Make_Function_Call (Loc,
5816 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
5817 Parameter_Associations =>
5819 Make_Selected_Component (Loc,
5821 Unchecked_Convert_To (
5822 Corresponding_Record_Type (Ptyp),
5823 New_Copy_Tree (Pref)),
5825 Make_Identifier (Loc, Name_uTask_Id))))));
5827 elsif Present (Storage_Size_Variable (Ptyp)) then
5829 -- Static Storage_Size pragma given for type: retrieve value
5830 -- from its allocated storage variable.
5834 Make_Function_Call (Loc,
5835 Name => New_Occurrence_Of (
5836 RTE (RE_Adjust_Storage_Size), Loc),
5837 Parameter_Associations =>
5840 Storage_Size_Variable (Ptyp), Loc)))));
5842 -- Get system default
5846 Make_Function_Call (Loc,
5849 RTE (RE_Default_Stack_Size), Loc))));
5852 Analyze_And_Resolve (N, Typ);
5860 when Attribute_Stream_Size =>
5862 Make_Integer_Literal (Loc, Intval => Get_Stream_Size (Ptyp)));
5863 Analyze_And_Resolve (N, Typ);
5869 -- 1. Deal with enumeration types with holes.
5870 -- 2. For floating-point, generate call to attribute function.
5871 -- 3. For other cases, deal with constraint checking.
5873 when Attribute_Succ => Succ : declare
5874 Etyp : constant Entity_Id := Base_Type (Ptyp);
5878 -- For enumeration types with non-standard representations, we
5879 -- expand typ'Succ (x) into
5881 -- Pos_To_Rep (Rep_To_Pos (x) + 1)
5883 -- If the representation is contiguous, we compute instead
5884 -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations.
5886 if Is_Enumeration_Type (Ptyp)
5887 and then Present (Enum_Pos_To_Rep (Etyp))
5889 if Has_Contiguous_Rep (Etyp) then
5891 Unchecked_Convert_To (Ptyp,
5894 Make_Integer_Literal (Loc,
5895 Enumeration_Rep (First_Literal (Ptyp))),
5897 Make_Function_Call (Loc,
5900 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
5902 Parameter_Associations =>
5904 Unchecked_Convert_To (Ptyp,
5907 Unchecked_Convert_To (Standard_Integer,
5908 Relocate_Node (First (Exprs))),
5910 Make_Integer_Literal (Loc, 1))),
5911 Rep_To_Pos_Flag (Ptyp, Loc))))));
5913 -- Add Boolean parameter True, to request program errror if
5914 -- we have a bad representation on our hands. Add False if
5915 -- checks are suppressed.
5917 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
5919 Make_Indexed_Component (Loc,
5922 (Enum_Pos_To_Rep (Etyp), Loc),
5923 Expressions => New_List (
5926 Make_Function_Call (Loc,
5929 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
5930 Parameter_Associations => Exprs),
5931 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
5934 Analyze_And_Resolve (N, Typ);
5936 -- For floating-point, we transform 'Succ into a call to the Succ
5937 -- floating-point attribute function in Fat_xxx (xxx is root type)
5939 elsif Is_Floating_Point_Type (Ptyp) then
5940 Expand_Fpt_Attribute_R (N);
5941 Analyze_And_Resolve (N, Typ);
5943 -- For modular types, nothing to do (no overflow, since wraps)
5945 elsif Is_Modular_Integer_Type (Ptyp) then
5948 -- For other types, if argument is marked as needing a range check or
5949 -- overflow checking is enabled, we must generate a check.
5951 elsif not Overflow_Checks_Suppressed (Ptyp)
5952 or else Do_Range_Check (First (Exprs))
5954 Set_Do_Range_Check (First (Exprs), False);
5955 Expand_Pred_Succ_Attribute (N);
5963 -- Transforms X'Tag into a direct reference to the tag of X
5965 when Attribute_Tag => Tag : declare
5967 Prefix_Is_Type : Boolean;
5970 if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then
5971 Ttyp := Entity (Pref);
5972 Prefix_Is_Type := True;
5975 Prefix_Is_Type := False;
5978 if Is_Class_Wide_Type (Ttyp) then
5979 Ttyp := Root_Type (Ttyp);
5982 Ttyp := Underlying_Type (Ttyp);
5984 -- Ada 2005: The type may be a synchronized tagged type, in which
5985 -- case the tag information is stored in the corresponding record.
5987 if Is_Concurrent_Type (Ttyp) then
5988 Ttyp := Corresponding_Record_Type (Ttyp);
5991 if Prefix_Is_Type then
5993 -- For VMs we leave the type attribute unexpanded because
5994 -- there's not a dispatching table to reference.
5996 if Tagged_Type_Expansion then
5998 Unchecked_Convert_To (RTE (RE_Tag),
6000 (Node (First_Elmt (Access_Disp_Table (Ttyp))), Loc)));
6001 Analyze_And_Resolve (N, RTE (RE_Tag));
6004 -- Ada 2005 (AI-251): The use of 'Tag in the sources always
6005 -- references the primary tag of the actual object. If 'Tag is
6006 -- applied to class-wide interface objects we generate code that
6007 -- displaces "this" to reference the base of the object.
6009 elsif Comes_From_Source (N)
6010 and then Is_Class_Wide_Type (Etype (Prefix (N)))
6011 and then Is_Interface (Etype (Prefix (N)))
6014 -- (To_Tag_Ptr (Prefix'Address)).all
6016 -- Note that Prefix'Address is recursively expanded into a call
6017 -- to Base_Address (Obj.Tag)
6019 -- Not needed for VM targets, since all handled by the VM
6021 if Tagged_Type_Expansion then
6023 Make_Explicit_Dereference (Loc,
6024 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
6025 Make_Attribute_Reference (Loc,
6026 Prefix => Relocate_Node (Pref),
6027 Attribute_Name => Name_Address))));
6028 Analyze_And_Resolve (N, RTE (RE_Tag));
6033 Make_Selected_Component (Loc,
6034 Prefix => Relocate_Node (Pref),
6036 New_Occurrence_Of (First_Tag_Component (Ttyp), Loc)));
6037 Analyze_And_Resolve (N, RTE (RE_Tag));
6045 -- Transforms 'Terminated attribute into a call to Terminated function
6047 when Attribute_Terminated => Terminated :
6049 -- The prefix of Terminated is of a task interface class-wide type.
6051 -- terminated (Task_Id (Pref._disp_get_task_id));
6053 if Ada_Version >= Ada_2005
6054 and then Ekind (Ptyp) = E_Class_Wide_Type
6055 and then Is_Interface (Ptyp)
6056 and then Is_Task_Interface (Ptyp)
6059 Make_Function_Call (Loc,
6061 New_Occurrence_Of (RTE (RE_Terminated), Loc),
6062 Parameter_Associations => New_List (
6063 Make_Unchecked_Type_Conversion (Loc,
6065 New_Occurrence_Of (RTE (RO_ST_Task_Id), Loc),
6067 Make_Selected_Component (Loc,
6069 New_Copy_Tree (Pref),
6071 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
6073 elsif Restricted_Profile then
6075 Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated)));
6079 Build_Call_With_Task (Pref, RTE (RE_Terminated)));
6082 Analyze_And_Resolve (N, Standard_Boolean);
6089 -- Transforms System'To_Address (X) and System.Address'Ref (X) into
6090 -- unchecked conversion from (integral) type of X to type address.
6092 when Attribute_To_Address | Attribute_Ref =>
6094 Unchecked_Convert_To (RTE (RE_Address),
6095 Relocate_Node (First (Exprs))));
6096 Analyze_And_Resolve (N, RTE (RE_Address));
6102 when Attribute_To_Any => To_Any : declare
6103 P_Type : constant Entity_Id := Etype (Pref);
6104 Decls : constant List_Id := New_List;
6110 Relocate_Node (First (Exprs))), Decls));
6111 Insert_Actions (N, Decls);
6112 Analyze_And_Resolve (N, RTE (RE_Any));
6119 -- Transforms 'Truncation into a call to the floating-point attribute
6120 -- function Truncation in Fat_xxx (where xxx is the root type).
6121 -- Expansion is avoided for cases the back end can handle directly.
6123 when Attribute_Truncation =>
6124 if not Is_Inline_Floating_Point_Attribute (N) then
6125 Expand_Fpt_Attribute_R (N);
6132 when Attribute_TypeCode => TypeCode : declare
6133 P_Type : constant Entity_Id := Etype (Pref);
6134 Decls : constant List_Id := New_List;
6136 Rewrite (N, Build_TypeCode_Call (Loc, P_Type, Decls));
6137 Insert_Actions (N, Decls);
6138 Analyze_And_Resolve (N, RTE (RE_TypeCode));
6141 -----------------------
6142 -- Unbiased_Rounding --
6143 -----------------------
6145 -- Transforms 'Unbiased_Rounding into a call to the floating-point
6146 -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
6147 -- root type). Expansion is avoided for cases the back end can handle
6150 when Attribute_Unbiased_Rounding =>
6151 if not Is_Inline_Floating_Point_Attribute (N) then
6152 Expand_Fpt_Attribute_R (N);
6159 when Attribute_Update =>
6160 Expand_Update_Attribute (N);
6166 -- The processing for VADS_Size is shared with Size
6172 -- For enumeration types with a standard representation, and for all
6173 -- other types, Val is handled by the back end. For enumeration types
6174 -- with a non-standard representation we use the _Pos_To_Rep array that
6175 -- was created when the type was frozen.
6177 when Attribute_Val => Val : declare
6178 Etyp : constant Entity_Id := Base_Type (Entity (Pref));
6181 if Is_Enumeration_Type (Etyp)
6182 and then Present (Enum_Pos_To_Rep (Etyp))
6184 if Has_Contiguous_Rep (Etyp) then
6186 Rep_Node : constant Node_Id :=
6187 Unchecked_Convert_To (Etyp,
6190 Make_Integer_Literal (Loc,
6191 Enumeration_Rep (First_Literal (Etyp))),
6193 (Convert_To (Standard_Integer,
6194 Relocate_Node (First (Exprs))))));
6198 Unchecked_Convert_To (Etyp,
6201 Make_Integer_Literal (Loc,
6202 Enumeration_Rep (First_Literal (Etyp))),
6204 Make_Function_Call (Loc,
6207 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
6208 Parameter_Associations => New_List (
6210 Rep_To_Pos_Flag (Etyp, Loc))))));
6215 Make_Indexed_Component (Loc,
6216 Prefix => New_Occurrence_Of (Enum_Pos_To_Rep (Etyp), Loc),
6217 Expressions => New_List (
6218 Convert_To (Standard_Integer,
6219 Relocate_Node (First (Exprs))))));
6222 Analyze_And_Resolve (N, Typ);
6224 -- If the argument is marked as requiring a range check then generate
6227 elsif Do_Range_Check (First (Exprs)) then
6228 Generate_Range_Check (First (Exprs), Etyp, CE_Range_Check_Failed);
6236 -- The code for valid is dependent on the particular types involved.
6237 -- See separate sections below for the generated code in each case.
6239 when Attribute_Valid => Valid : declare
6240 Btyp : Entity_Id := Base_Type (Ptyp);
6243 Save_Validity_Checks_On : constant Boolean := Validity_Checks_On;
6244 -- Save the validity checking mode. We always turn off validity
6245 -- checking during process of 'Valid since this is one place
6246 -- where we do not want the implicit validity checks to intefere
6247 -- with the explicit validity check that the programmer is doing.
6249 function Make_Range_Test return Node_Id;
6250 -- Build the code for a range test of the form
6251 -- Btyp!(Pref) in Btyp!(Ptyp'First) .. Btyp!(Ptyp'Last)
6253 ---------------------
6254 -- Make_Range_Test --
6255 ---------------------
6257 function Make_Range_Test return Node_Id is
6258 Temp : constant Node_Id := Duplicate_Subexpr (Pref);
6261 -- The value whose validity is being checked has been captured in
6262 -- an object declaration. We certainly don't want this object to
6263 -- appear valid because the declaration initializes it.
6265 if Is_Entity_Name (Temp) then
6266 Set_Is_Known_Valid (Entity (Temp), False);
6272 Unchecked_Convert_To (Btyp, Temp),
6276 Unchecked_Convert_To (Btyp,
6277 Make_Attribute_Reference (Loc,
6278 Prefix => New_Occurrence_Of (Ptyp, Loc),
6279 Attribute_Name => Name_First)),
6281 Unchecked_Convert_To (Btyp,
6282 Make_Attribute_Reference (Loc,
6283 Prefix => New_Occurrence_Of (Ptyp, Loc),
6284 Attribute_Name => Name_Last))));
6285 end Make_Range_Test;
6287 -- Start of processing for Attribute_Valid
6290 -- Do not expand sourced code 'Valid reference in CodePeer mode,
6291 -- will be handled by the back-end directly.
6293 if CodePeer_Mode and then Comes_From_Source (N) then
6297 -- Turn off validity checks. We do not want any implicit validity
6298 -- checks to intefere with the explicit check from the attribute
6300 Validity_Checks_On := False;
6302 -- Retrieve the base type. Handle the case where the base type is a
6303 -- private enumeration type.
6305 if Is_Private_Type (Btyp) and then Present (Full_View (Btyp)) then
6306 Btyp := Full_View (Btyp);
6309 -- Floating-point case. This case is handled by the Valid attribute
6310 -- code in the floating-point attribute run-time library.
6312 if Is_Floating_Point_Type (Ptyp) then
6313 Float_Valid : declare
6317 function Get_Fat_Entity (Nam : Name_Id) return Entity_Id;
6318 -- Return entity for Pkg.Nam
6320 --------------------
6321 -- Get_Fat_Entity --
6322 --------------------
6324 function Get_Fat_Entity (Nam : Name_Id) return Entity_Id is
6325 Exp_Name : constant Node_Id :=
6326 Make_Selected_Component (Loc,
6327 Prefix => New_Occurrence_Of (RTE (Pkg), Loc),
6328 Selector_Name => Make_Identifier (Loc, Nam));
6330 Find_Selected_Component (Exp_Name);
6331 return Entity (Exp_Name);
6334 -- Start of processing for Float_Valid
6337 case Float_Rep (Btyp) is
6339 -- The AAMP back end handles Valid for floating-point types
6342 Analyze_And_Resolve (Pref, Ptyp);
6343 Set_Etype (N, Standard_Boolean);
6347 Find_Fat_Info (Ptyp, Ftp, Pkg);
6349 -- If the prefix is a reverse SSO component, or is
6350 -- possibly unaligned, first create a temporary copy
6351 -- that is in native SSO, and properly aligned. Make it
6352 -- Volatile to prevent folding in the back-end. Note
6353 -- that we use an intermediate constrained string type
6354 -- to initialize the temporary, as the value at hand
6355 -- might be invalid, and in that case it cannot be copied
6356 -- using a floating point register.
6358 if In_Reverse_Storage_Order_Object (Pref)
6360 Is_Possibly_Unaligned_Object (Pref)
6363 Temp : constant Entity_Id :=
6364 Make_Temporary (Loc, 'F');
6366 Fat_S : constant Entity_Id :=
6367 Get_Fat_Entity (Name_S);
6368 -- Constrained string subtype of appropriate size
6370 Fat_P : constant Entity_Id :=
6371 Get_Fat_Entity (Name_P);
6374 Decl : constant Node_Id :=
6375 Make_Object_Declaration (Loc,
6376 Defining_Identifier => Temp,
6377 Aliased_Present => True,
6378 Object_Definition =>
6379 New_Occurrence_Of (Ptyp, Loc));
6382 Set_Aspect_Specifications (Decl, New_List (
6383 Make_Aspect_Specification (Loc,
6385 Make_Identifier (Loc, Name_Volatile))));
6391 Make_Assignment_Statement (Loc,
6393 Make_Explicit_Dereference (Loc,
6395 Unchecked_Convert_To (Fat_P,
6396 Make_Attribute_Reference (Loc,
6398 New_Occurrence_Of (Temp, Loc),
6400 Name_Unrestricted_Access))),
6402 Unchecked_Convert_To (Fat_S,
6403 Relocate_Node (Pref)))),
6405 Suppress => All_Checks);
6407 Rewrite (Pref, New_Occurrence_Of (Temp, Loc));
6411 -- We now have an object of the proper endianness and
6412 -- alignment, and can construct a Valid attribute.
6414 -- We make sure the prefix of this valid attribute is
6415 -- marked as not coming from source, to avoid losing
6416 -- warnings from 'Valid looking like a possible update.
6418 Set_Comes_From_Source (Pref, False);
6420 Expand_Fpt_Attribute
6421 (N, Pkg, Name_Valid,
6423 Make_Attribute_Reference (Loc,
6424 Prefix => Unchecked_Convert_To (Ftp, Pref),
6425 Attribute_Name => Name_Unrestricted_Access)));
6428 -- One more task, we still need a range check. Required
6429 -- only if we have a constraint, since the Valid routine
6430 -- catches infinities properly (infinities are never valid).
6432 -- The way we do the range check is simply to create the
6433 -- expression: Valid (N) and then Base_Type(Pref) in Typ.
6435 if not Subtypes_Statically_Match (Ptyp, Btyp) then
6438 Left_Opnd => Relocate_Node (N),
6441 Left_Opnd => Convert_To (Btyp, Pref),
6442 Right_Opnd => New_Occurrence_Of (Ptyp, Loc))));
6446 -- Enumeration type with holes
6448 -- For enumeration types with holes, the Pos value constructed by
6449 -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
6450 -- second argument of False returns minus one for an invalid value,
6451 -- and the non-negative pos value for a valid value, so the
6452 -- expansion of X'Valid is simply:
6454 -- type(X)'Pos (X) >= 0
6456 -- We can't quite generate it that way because of the requirement
6457 -- for the non-standard second argument of False in the resulting
6458 -- rep_to_pos call, so we have to explicitly create:
6460 -- _rep_to_pos (X, False) >= 0
6462 -- If we have an enumeration subtype, we also check that the
6463 -- value is in range:
6465 -- _rep_to_pos (X, False) >= 0
6467 -- (X >= type(X)'First and then type(X)'Last <= X)
6469 elsif Is_Enumeration_Type (Ptyp)
6470 and then Present (Enum_Pos_To_Rep (Btyp))
6475 Make_Function_Call (Loc,
6477 New_Occurrence_Of (TSS (Btyp, TSS_Rep_To_Pos), Loc),
6478 Parameter_Associations => New_List (
6480 New_Occurrence_Of (Standard_False, Loc))),
6481 Right_Opnd => Make_Integer_Literal (Loc, 0));
6485 (Type_Low_Bound (Ptyp) /= Type_Low_Bound (Btyp)
6487 Type_High_Bound (Ptyp) /= Type_High_Bound (Btyp))
6489 -- The call to Make_Range_Test will create declarations
6490 -- that need a proper insertion point, but Pref is now
6491 -- attached to a node with no ancestor. Attach to tree
6492 -- even if it is to be rewritten below.
6494 Set_Parent (Tst, Parent (N));
6498 Left_Opnd => Make_Range_Test,
6504 -- Fortran convention booleans
6506 -- For the very special case of Fortran convention booleans, the
6507 -- value is always valid, since it is an integer with the semantics
6508 -- that non-zero is true, and any value is permissible.
6510 elsif Is_Boolean_Type (Ptyp)
6511 and then Convention (Ptyp) = Convention_Fortran
6513 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
6515 -- For biased representations, we will be doing an unchecked
6516 -- conversion without unbiasing the result. That means that the range
6517 -- test has to take this into account, and the proper form of the
6520 -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length)
6522 elsif Has_Biased_Representation (Ptyp) then
6523 Btyp := RTE (RE_Unsigned_32);
6527 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
6529 Unchecked_Convert_To (Btyp,
6530 Make_Attribute_Reference (Loc,
6531 Prefix => New_Occurrence_Of (Ptyp, Loc),
6532 Attribute_Name => Name_Range_Length))));
6534 -- For all other scalar types, what we want logically is a
6537 -- X in type(X)'First .. type(X)'Last
6539 -- But that's precisely what won't work because of possible
6540 -- unwanted optimization (and indeed the basic motivation for
6541 -- the Valid attribute is exactly that this test does not work).
6542 -- What will work is:
6544 -- Btyp!(X) >= Btyp!(type(X)'First)
6546 -- Btyp!(X) <= Btyp!(type(X)'Last)
6548 -- where Btyp is an integer type large enough to cover the full
6549 -- range of possible stored values (i.e. it is chosen on the basis
6550 -- of the size of the type, not the range of the values). We write
6551 -- this as two tests, rather than a range check, so that static
6552 -- evaluation will easily remove either or both of the checks if
6553 -- they can be -statically determined to be true (this happens
6554 -- when the type of X is static and the range extends to the full
6555 -- range of stored values).
6557 -- Unsigned types. Note: it is safe to consider only whether the
6558 -- subtype is unsigned, since we will in that case be doing all
6559 -- unsigned comparisons based on the subtype range. Since we use the
6560 -- actual subtype object size, this is appropriate.
6562 -- For example, if we have
6564 -- subtype x is integer range 1 .. 200;
6565 -- for x'Object_Size use 8;
6567 -- Now the base type is signed, but objects of this type are bits
6568 -- unsigned, and doing an unsigned test of the range 1 to 200 is
6569 -- correct, even though a value greater than 127 looks signed to a
6570 -- signed comparison.
6572 elsif Is_Unsigned_Type (Ptyp) then
6573 if Esize (Ptyp) <= 32 then
6574 Btyp := RTE (RE_Unsigned_32);
6576 Btyp := RTE (RE_Unsigned_64);
6579 Rewrite (N, Make_Range_Test);
6584 if Esize (Ptyp) <= Esize (Standard_Integer) then
6585 Btyp := Standard_Integer;
6587 Btyp := Universal_Integer;
6590 Rewrite (N, Make_Range_Test);
6593 -- If a predicate is present, then we do the predicate test, even if
6594 -- within the predicate function (infinite recursion is warned about
6595 -- in Sem_Attr in that case).
6598 Pred_Func : constant Entity_Id := Predicate_Function (Ptyp);
6601 if Present (Pred_Func) then
6604 Left_Opnd => Relocate_Node (N),
6605 Right_Opnd => Make_Predicate_Call (Ptyp, Pref)));
6609 Analyze_And_Resolve (N, Standard_Boolean);
6610 Validity_Checks_On := Save_Validity_Checks_On;
6617 when Attribute_Valid_Scalars => Valid_Scalars : declare
6621 if Present (Underlying_Type (Ptyp)) then
6622 Ftyp := Underlying_Type (Ptyp);
6627 -- Replace by True if no scalar parts
6629 if not Scalar_Part_Present (Ftyp) then
6630 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
6632 -- For scalar types, Valid_Scalars is the same as Valid
6634 elsif Is_Scalar_Type (Ftyp) then
6636 Make_Attribute_Reference (Loc,
6637 Attribute_Name => Name_Valid,
6640 -- For array types, we construct a function that determines if there
6641 -- are any non-valid scalar subcomponents, and call the function.
6642 -- We only do this for arrays whose component type needs checking
6644 elsif Is_Array_Type (Ftyp)
6645 and then Scalar_Part_Present (Component_Type (Ftyp))
6648 Make_Function_Call (Loc,
6650 New_Occurrence_Of (Build_Array_VS_Func (Ftyp, N), Loc),
6651 Parameter_Associations => New_List (Pref)));
6653 -- For record types, we construct a function that determines if there
6654 -- are any non-valid scalar subcomponents, and call the function.
6656 elsif Is_Record_Type (Ftyp)
6657 and then Nkind (Type_Definition (Declaration_Node (Ftyp))) =
6661 Make_Function_Call (Loc,
6663 New_Occurrence_Of (Build_Record_VS_Func (Ftyp, N), Loc),
6664 Parameter_Associations => New_List (Pref)));
6666 -- Other record types or types with discriminants
6668 elsif Is_Record_Type (Ftyp) or else Has_Discriminants (Ptyp) then
6670 -- Build expression with list of equality tests
6678 X := New_Occurrence_Of (Standard_True, Loc);
6679 C := First_Component_Or_Discriminant (Ptyp);
6680 while Present (C) loop
6681 if not Scalar_Part_Present (Etype (C)) then
6683 elsif Is_Scalar_Type (Etype (C)) then
6686 A := Name_Valid_Scalars;
6693 Make_Attribute_Reference (Loc,
6694 Attribute_Name => A,
6696 Make_Selected_Component (Loc,
6698 Duplicate_Subexpr (Pref, Name_Req => True),
6700 New_Occurrence_Of (C, Loc))));
6702 Next_Component_Or_Discriminant (C);
6708 -- For all other types, result is True
6711 Rewrite (N, New_Occurrence_Of (Standard_Boolean, Loc));
6714 -- Result is always boolean, but never static
6716 Analyze_And_Resolve (N, Standard_Boolean);
6717 Set_Is_Static_Expression (N, False);
6724 -- Value attribute is handled in separate unit Exp_Imgv
6726 when Attribute_Value =>
6727 Exp_Imgv.Expand_Value_Attribute (N);
6733 -- The processing for Value_Size shares the processing for Size
6739 -- The processing for Version shares the processing for Body_Version
6745 -- Wide_Image attribute is handled in separate unit Exp_Imgv
6747 when Attribute_Wide_Image =>
6748 Exp_Imgv.Expand_Wide_Image_Attribute (N);
6750 ---------------------
6751 -- Wide_Wide_Image --
6752 ---------------------
6754 -- Wide_Wide_Image attribute is handled in separate unit Exp_Imgv
6756 when Attribute_Wide_Wide_Image =>
6757 Exp_Imgv.Expand_Wide_Wide_Image_Attribute (N);
6763 -- We expand typ'Wide_Value (X) into
6766 -- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
6768 -- Wide_String_To_String is a runtime function that converts its wide
6769 -- string argument to String, converting any non-translatable characters
6770 -- into appropriate escape sequences. This preserves the required
6771 -- semantics of Wide_Value in all cases, and results in a very simple
6772 -- implementation approach.
6774 -- Note: for this approach to be fully standard compliant for the cases
6775 -- where typ is Wide_Character and Wide_Wide_Character, the encoding
6776 -- method must cover the entire character range (e.g. UTF-8). But that
6777 -- is a reasonable requirement when dealing with encoded character
6778 -- sequences. Presumably if one of the restrictive encoding mechanisms
6779 -- is in use such as Shift-JIS, then characters that cannot be
6780 -- represented using this encoding will not appear in any case.
6782 when Attribute_Wide_Value => Wide_Value :
6785 Make_Attribute_Reference (Loc,
6787 Attribute_Name => Name_Value,
6789 Expressions => New_List (
6790 Make_Function_Call (Loc,
6792 New_Occurrence_Of (RTE (RE_Wide_String_To_String), Loc),
6794 Parameter_Associations => New_List (
6795 Relocate_Node (First (Exprs)),
6796 Make_Integer_Literal (Loc,
6797 Intval => Int (Wide_Character_Encoding_Method)))))));
6799 Analyze_And_Resolve (N, Typ);
6802 ---------------------
6803 -- Wide_Wide_Value --
6804 ---------------------
6806 -- We expand typ'Wide_Value_Value (X) into
6809 -- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
6811 -- Wide_Wide_String_To_String is a runtime function that converts its
6812 -- wide string argument to String, converting any non-translatable
6813 -- characters into appropriate escape sequences. This preserves the
6814 -- required semantics of Wide_Wide_Value in all cases, and results in a
6815 -- very simple implementation approach.
6817 -- It's not quite right where typ = Wide_Wide_Character, because the
6818 -- encoding method may not cover the whole character type ???
6820 when Attribute_Wide_Wide_Value => Wide_Wide_Value :
6823 Make_Attribute_Reference (Loc,
6825 Attribute_Name => Name_Value,
6827 Expressions => New_List (
6828 Make_Function_Call (Loc,
6831 (RTE (RE_Wide_Wide_String_To_String), Loc),
6833 Parameter_Associations => New_List (
6834 Relocate_Node (First (Exprs)),
6835 Make_Integer_Literal (Loc,
6836 Intval => Int (Wide_Character_Encoding_Method)))))));
6838 Analyze_And_Resolve (N, Typ);
6839 end Wide_Wide_Value;
6841 ---------------------
6842 -- Wide_Wide_Width --
6843 ---------------------
6845 -- Wide_Wide_Width attribute is handled in separate unit Exp_Imgv
6847 when Attribute_Wide_Wide_Width =>
6848 Exp_Imgv.Expand_Width_Attribute (N, Wide_Wide);
6854 -- Wide_Width attribute is handled in separate unit Exp_Imgv
6856 when Attribute_Wide_Width =>
6857 Exp_Imgv.Expand_Width_Attribute (N, Wide);
6863 -- Width attribute is handled in separate unit Exp_Imgv
6865 when Attribute_Width =>
6866 Exp_Imgv.Expand_Width_Attribute (N, Normal);
6872 when Attribute_Write => Write : declare
6873 P_Type : constant Entity_Id := Entity (Pref);
6874 U_Type : constant Entity_Id := Underlying_Type (P_Type);
6882 -- If no underlying type, we have an error that will be diagnosed
6883 -- elsewhere, so here we just completely ignore the expansion.
6889 -- Stream operations can appear in user code even if the restriction
6890 -- No_Streams is active (for example, when instantiating a predefined
6891 -- container). In that case rewrite the attribute as a Raise to
6892 -- prevent any run-time use.
6894 if Restriction_Active (No_Streams) then
6896 Make_Raise_Program_Error (Sloc (N),
6897 Reason => PE_Stream_Operation_Not_Allowed));
6898 Set_Etype (N, U_Type);
6902 -- The simple case, if there is a TSS for Write, just call it
6904 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Write);
6906 if Present (Pname) then
6910 -- If there is a Stream_Convert pragma, use it, we rewrite
6912 -- sourcetyp'Output (stream, Item)
6916 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
6918 -- where strmwrite is the given Write function that converts an
6919 -- argument of type sourcetyp or a type acctyp, from which it is
6920 -- derived to type strmtyp. The conversion to acttyp is required
6921 -- for the derived case.
6923 Prag := Get_Stream_Convert_Pragma (P_Type);
6925 if Present (Prag) then
6927 Next (Next (First (Pragma_Argument_Associations (Prag))));
6928 Wfunc := Entity (Expression (Arg3));
6931 Make_Attribute_Reference (Loc,
6932 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
6933 Attribute_Name => Name_Output,
6934 Expressions => New_List (
6935 Relocate_Node (First (Exprs)),
6936 Make_Function_Call (Loc,
6937 Name => New_Occurrence_Of (Wfunc, Loc),
6938 Parameter_Associations => New_List (
6939 OK_Convert_To (Etype (First_Formal (Wfunc)),
6940 Relocate_Node (Next (First (Exprs)))))))));
6945 -- For elementary types, we call the W_xxx routine directly
6947 elsif Is_Elementary_Type (U_Type) then
6948 Rewrite (N, Build_Elementary_Write_Call (N));
6954 elsif Is_Array_Type (U_Type) then
6955 Build_Array_Write_Procedure (N, U_Type, Decl, Pname);
6956 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
6958 -- Tagged type case, use the primitive Write function. Note that
6959 -- this will dispatch in the class-wide case which is what we want
6961 elsif Is_Tagged_Type (U_Type) then
6962 Pname := Find_Prim_Op (U_Type, TSS_Stream_Write);
6964 -- All other record type cases, including protected records.
6965 -- The latter only arise for expander generated code for
6966 -- handling shared passive partition access.
6970 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
6972 -- Ada 2005 (AI-216): Program_Error is raised when executing
6973 -- the default implementation of the Write attribute of an
6974 -- Unchecked_Union type. However, if the 'Write reference is
6975 -- within the generated Output stream procedure, Write outputs
6976 -- the components, and the default values of the discriminant
6977 -- are streamed by the Output procedure itself.
6979 if Is_Unchecked_Union (Base_Type (U_Type))
6980 and not Is_TSS (Current_Scope, TSS_Stream_Output)
6983 Make_Raise_Program_Error (Loc,
6984 Reason => PE_Unchecked_Union_Restriction));
6987 if Has_Discriminants (U_Type)
6989 (Discriminant_Default_Value (First_Discriminant (U_Type)))
6991 Build_Mutable_Record_Write_Procedure
6992 (Loc, Full_Base (U_Type), Decl, Pname);
6994 Build_Record_Write_Procedure
6995 (Loc, Full_Base (U_Type), Decl, Pname);
6998 Insert_Action (N, Decl);
7002 -- If we fall through, Pname is the procedure to be called
7004 Rewrite_Stream_Proc_Call (Pname);
7007 -- Component_Size is handled by the back end, unless the component size
7008 -- is known at compile time, which is always true in the packed array
7009 -- case. It is important that the packed array case is handled in the
7010 -- front end (see Eval_Attribute) since the back end would otherwise get
7011 -- confused by the equivalent packed array type.
7013 when Attribute_Component_Size =>
7016 -- The following attributes are handled by the back end (except that
7017 -- static cases have already been evaluated during semantic processing,
7018 -- but in any case the back end should not count on this).
7020 -- The back end also handles the non-class-wide cases of Size
7022 when Attribute_Bit_Order |
7023 Attribute_Code_Address |
7024 Attribute_Definite |
7026 Attribute_Null_Parameter |
7027 Attribute_Passed_By_Reference |
7028 Attribute_Pool_Address |
7029 Attribute_Scalar_Storage_Order =>
7032 -- The following attributes are also handled by the back end, but return
7033 -- a universal integer result, so may need a conversion for checking
7034 -- that the result is in range.
7036 when Attribute_Aft |
7037 Attribute_Max_Alignment_For_Allocation =>
7038 Apply_Universal_Integer_Attribute_Checks (N);
7040 -- The following attributes should not appear at this stage, since they
7041 -- have already been handled by the analyzer (and properly rewritten
7042 -- with corresponding values or entities to represent the right values)
7044 when Attribute_Abort_Signal |
7045 Attribute_Address_Size |
7046 Attribute_Atomic_Always_Lock_Free |
7049 Attribute_Compiler_Version |
7050 Attribute_Default_Bit_Order |
7051 Attribute_Default_Scalar_Storage_Order |
7058 Attribute_Fast_Math |
7059 Attribute_First_Valid |
7060 Attribute_Has_Access_Values |
7061 Attribute_Has_Discriminants |
7062 Attribute_Has_Tagged_Values |
7064 Attribute_Last_Valid |
7065 Attribute_Library_Level |
7066 Attribute_Lock_Free |
7067 Attribute_Machine_Emax |
7068 Attribute_Machine_Emin |
7069 Attribute_Machine_Mantissa |
7070 Attribute_Machine_Overflows |
7071 Attribute_Machine_Radix |
7072 Attribute_Machine_Rounds |
7073 Attribute_Maximum_Alignment |
7074 Attribute_Model_Emin |
7075 Attribute_Model_Epsilon |
7076 Attribute_Model_Mantissa |
7077 Attribute_Model_Small |
7079 Attribute_Partition_ID |
7081 Attribute_Restriction_Set |
7082 Attribute_Safe_Emax |
7083 Attribute_Safe_First |
7084 Attribute_Safe_Large |
7085 Attribute_Safe_Last |
7086 Attribute_Safe_Small |
7088 Attribute_Signed_Zeros |
7090 Attribute_Storage_Unit |
7091 Attribute_Stub_Type |
7092 Attribute_System_Allocator_Alignment |
7093 Attribute_Target_Name |
7094 Attribute_Type_Class |
7095 Attribute_Type_Key |
7096 Attribute_Unconstrained_Array |
7097 Attribute_Universal_Literal_String |
7098 Attribute_Wchar_T_Size |
7099 Attribute_Word_Size =>
7100 raise Program_Error;
7102 -- The Asm_Input and Asm_Output attributes are not expanded at this
7103 -- stage, but will be eliminated in the expansion of the Asm call, see
7104 -- Exp_Intr for details. So the back end will never see these either.
7106 when Attribute_Asm_Input |
7107 Attribute_Asm_Output =>
7111 -- Note: as mentioned earlier, individual sections of the above case
7112 -- statement assume there is no code after the case statement, and are
7113 -- legitimately allowed to execute return statements if they have nothing
7114 -- more to do, so DO NOT add code at this point.
7117 when RE_Not_Available =>
7119 end Expand_N_Attribute_Reference;
7121 --------------------------------
7122 -- Expand_Pred_Succ_Attribute --
7123 --------------------------------
7125 -- For typ'Pred (exp), we generate the check
7127 -- [constraint_error when exp = typ'Base'First]
7129 -- Similarly, for typ'Succ (exp), we generate the check
7131 -- [constraint_error when exp = typ'Base'Last]
7133 -- These checks are not generated for modular types, since the proper
7134 -- semantics for Succ and Pred on modular types is to wrap, not raise CE.
7135 -- We also suppress these checks if we are the right side of an assignment
7136 -- statement or the expression of an object declaration, where the flag
7137 -- Suppress_Assignment_Checks is set for the assignment/declaration.
7139 procedure Expand_Pred_Succ_Attribute (N : Node_Id) is
7140 Loc : constant Source_Ptr := Sloc (N);
7141 P : constant Node_Id := Parent (N);
7145 if Attribute_Name (N) = Name_Pred then
7151 if not Nkind_In (P, N_Assignment_Statement, N_Object_Declaration)
7152 or else not Suppress_Assignment_Checks (P)
7155 Make_Raise_Constraint_Error (Loc,
7159 Duplicate_Subexpr_Move_Checks (First (Expressions (N))),
7161 Make_Attribute_Reference (Loc,
7163 New_Occurrence_Of (Base_Type (Etype (Prefix (N))), Loc),
7164 Attribute_Name => Cnam)),
7165 Reason => CE_Overflow_Check_Failed));
7167 end Expand_Pred_Succ_Attribute;
7169 -----------------------------
7170 -- Expand_Update_Attribute --
7171 -----------------------------
7173 procedure Expand_Update_Attribute (N : Node_Id) is
7174 procedure Process_Component_Or_Element_Update
7179 -- Generate the statements necessary to update a single component or an
7180 -- element of the prefix. The code is inserted before the attribute N.
7181 -- Temp denotes the entity of the anonymous object created to reflect
7182 -- the changes in values. Comp is the component/index expression to be
7183 -- updated. Expr is an expression yielding the new value of Comp. Typ
7184 -- is the type of the prefix of attribute Update.
7186 procedure Process_Range_Update
7191 -- Generate the statements necessary to update a slice of the prefix.
7192 -- The code is inserted before the attribute N. Temp denotes the entity
7193 -- of the anonymous object created to reflect the changes in values.
7194 -- Comp is range of the slice to be updated. Expr is an expression
7195 -- yielding the new value of Comp. Typ is the type of the prefix of
7196 -- attribute Update.
7198 -----------------------------------------
7199 -- Process_Component_Or_Element_Update --
7200 -----------------------------------------
7202 procedure Process_Component_Or_Element_Update
7208 Loc : constant Source_Ptr := Sloc (Comp);
7213 -- An array element may be modified by the following relations
7214 -- depending on the number of dimensions:
7216 -- 1 => Expr -- one dimensional update
7217 -- (1, ..., N) => Expr -- multi dimensional update
7219 -- The above forms are converted in assignment statements where the
7220 -- left hand side is an indexed component:
7222 -- Temp (1) := Expr; -- one dimensional update
7223 -- Temp (1, ..., N) := Expr; -- multi dimensional update
7225 if Is_Array_Type (Typ) then
7227 -- The index expressions of a multi dimensional array update
7228 -- appear as an aggregate.
7230 if Nkind (Comp) = N_Aggregate then
7231 Exprs := New_Copy_List_Tree (Expressions (Comp));
7233 Exprs := New_List (Relocate_Node (Comp));
7237 Make_Indexed_Component (Loc,
7238 Prefix => New_Occurrence_Of (Temp, Loc),
7239 Expressions => Exprs);
7241 -- A record component update appears in the following form:
7245 -- The above relation is transformed into an assignment statement
7246 -- where the left hand side is a selected component:
7248 -- Temp.Comp := Expr;
7250 else pragma Assert (Is_Record_Type (Typ));
7252 Make_Selected_Component (Loc,
7253 Prefix => New_Occurrence_Of (Temp, Loc),
7254 Selector_Name => Relocate_Node (Comp));
7258 Make_Assignment_Statement (Loc,
7260 Expression => Relocate_Node (Expr)));
7261 end Process_Component_Or_Element_Update;
7263 --------------------------
7264 -- Process_Range_Update --
7265 --------------------------
7267 procedure Process_Range_Update
7273 Index_Typ : constant Entity_Id := Etype (First_Index (Typ));
7274 Loc : constant Source_Ptr := Sloc (Comp);
7278 -- A range update appears as
7280 -- (Low .. High => Expr)
7282 -- The above construct is transformed into a loop that iterates over
7283 -- the given range and modifies the corresponding array values to the
7286 -- for Index in Low .. High loop
7287 -- Temp (<Index_Typ> (Index)) := Expr;
7290 Index := Make_Temporary (Loc, 'I');
7293 Make_Loop_Statement (Loc,
7295 Make_Iteration_Scheme (Loc,
7296 Loop_Parameter_Specification =>
7297 Make_Loop_Parameter_Specification (Loc,
7298 Defining_Identifier => Index,
7299 Discrete_Subtype_Definition => Relocate_Node (Comp))),
7301 Statements => New_List (
7302 Make_Assignment_Statement (Loc,
7304 Make_Indexed_Component (Loc,
7305 Prefix => New_Occurrence_Of (Temp, Loc),
7306 Expressions => New_List (
7307 Convert_To (Index_Typ,
7308 New_Occurrence_Of (Index, Loc)))),
7309 Expression => Relocate_Node (Expr))),
7311 End_Label => Empty));
7312 end Process_Range_Update;
7316 Aggr : constant Node_Id := First (Expressions (N));
7317 Loc : constant Source_Ptr := Sloc (N);
7318 Pref : constant Node_Id := Prefix (N);
7319 Typ : constant Entity_Id := Etype (Pref);
7322 CW_Temp : Entity_Id;
7327 -- Start of processing for Expand_Update_Attribute
7330 -- Create the anonymous object to store the value of the prefix and
7331 -- capture subsequent changes in value.
7333 Temp := Make_Temporary (Loc, 'T', Pref);
7335 -- Preserve the tag of the prefix by offering a specific view of the
7336 -- class-wide version of the prefix.
7338 if Is_Tagged_Type (Typ) then
7341 -- CW_Temp : Typ'Class := Typ'Class (Pref);
7343 CW_Temp := Make_Temporary (Loc, 'T');
7344 CW_Typ := Class_Wide_Type (Typ);
7347 Make_Object_Declaration (Loc,
7348 Defining_Identifier => CW_Temp,
7349 Object_Definition => New_Occurrence_Of (CW_Typ, Loc),
7351 Convert_To (CW_Typ, Relocate_Node (Pref))));
7354 -- Temp : Typ renames Typ (CW_Temp);
7357 Make_Object_Renaming_Declaration (Loc,
7358 Defining_Identifier => Temp,
7359 Subtype_Mark => New_Occurrence_Of (Typ, Loc),
7361 Convert_To (Typ, New_Occurrence_Of (CW_Temp, Loc))));
7367 -- Temp : Typ := Pref;
7370 Make_Object_Declaration (Loc,
7371 Defining_Identifier => Temp,
7372 Object_Definition => New_Occurrence_Of (Typ, Loc),
7373 Expression => Relocate_Node (Pref)));
7376 -- Process the update aggregate
7378 Assoc := First (Component_Associations (Aggr));
7379 while Present (Assoc) loop
7380 Comp := First (Choices (Assoc));
7381 Expr := Expression (Assoc);
7382 while Present (Comp) loop
7383 if Nkind (Comp) = N_Range then
7384 Process_Range_Update (Temp, Comp, Expr, Typ);
7386 Process_Component_Or_Element_Update (Temp, Comp, Expr, Typ);
7395 -- The attribute is replaced by a reference to the anonymous object
7397 Rewrite (N, New_Occurrence_Of (Temp, Loc));
7399 end Expand_Update_Attribute;
7405 procedure Find_Fat_Info
7407 Fat_Type : out Entity_Id;
7408 Fat_Pkg : out RE_Id)
7410 Rtyp : constant Entity_Id := Root_Type (T);
7413 -- All we do is use the root type (historically this dealt with
7414 -- VAX-float .. to be cleaned up further later ???)
7418 if Fat_Type = Standard_Short_Float then
7419 Fat_Pkg := RE_Attr_Short_Float;
7421 elsif Fat_Type = Standard_Float then
7422 Fat_Pkg := RE_Attr_Float;
7424 elsif Fat_Type = Standard_Long_Float then
7425 Fat_Pkg := RE_Attr_Long_Float;
7427 elsif Fat_Type = Standard_Long_Long_Float then
7428 Fat_Pkg := RE_Attr_Long_Long_Float;
7430 -- Universal real (which is its own root type) is treated as being
7431 -- equivalent to Standard.Long_Long_Float, since it is defined to
7432 -- have the same precision as the longest Float type.
7434 elsif Fat_Type = Universal_Real then
7435 Fat_Type := Standard_Long_Long_Float;
7436 Fat_Pkg := RE_Attr_Long_Long_Float;
7439 raise Program_Error;
7443 ----------------------------
7444 -- Find_Stream_Subprogram --
7445 ----------------------------
7447 function Find_Stream_Subprogram
7449 Nam : TSS_Name_Type) return Entity_Id
7451 Base_Typ : constant Entity_Id := Base_Type (Typ);
7452 Ent : constant Entity_Id := TSS (Typ, Nam);
7454 function Is_Available (Entity : RE_Id) return Boolean;
7455 pragma Inline (Is_Available);
7456 -- Function to check whether the specified run-time call is available
7457 -- in the run time used. In the case of a configurable run time, it
7458 -- is normal that some subprograms are not there.
7460 -- I don't understand this routine at all, why is this not just a
7461 -- call to RTE_Available? And if for some reason we need a different
7462 -- routine with different semantics, why is not in Rtsfind ???
7468 function Is_Available (Entity : RE_Id) return Boolean is
7470 -- Assume that the unit will always be available when using a
7471 -- "normal" (not configurable) run time.
7473 return not Configurable_Run_Time_Mode or else RTE_Available (Entity);
7476 -- Start of processing for Find_Stream_Subprogram
7479 if Present (Ent) then
7483 -- Stream attributes for strings are expanded into library calls. The
7484 -- following checks are disabled when the run-time is not available or
7485 -- when compiling predefined types due to bootstrap issues. As a result,
7486 -- the compiler will generate in-place stream routines for string types
7487 -- that appear in GNAT's library, but will generate calls via rtsfind
7488 -- to library routines for user code.
7490 -- This is disabled for AAMP, to avoid creating dependences on files not
7491 -- supported in the AAMP library (such as s-fileio.adb).
7493 -- Note: In the case of using a configurable run time, it is very likely
7494 -- that stream routines for string types are not present (they require
7495 -- file system support). In this case, the specific stream routines for
7496 -- strings are not used, relying on the regular stream mechanism
7497 -- instead. That is why we include the test Is_Available when dealing
7498 -- with these cases.
7500 if not AAMP_On_Target
7502 not Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit))
7504 -- Storage_Array as defined in package System.Storage_Elements
7506 if Is_RTE (Base_Typ, RE_Storage_Array) then
7508 -- Case of No_Stream_Optimizations restriction active
7510 if Restriction_Active (No_Stream_Optimizations) then
7511 if Nam = TSS_Stream_Input
7512 and then Is_Available (RE_Storage_Array_Input)
7514 return RTE (RE_Storage_Array_Input);
7516 elsif Nam = TSS_Stream_Output
7517 and then Is_Available (RE_Storage_Array_Output)
7519 return RTE (RE_Storage_Array_Output);
7521 elsif Nam = TSS_Stream_Read
7522 and then Is_Available (RE_Storage_Array_Read)
7524 return RTE (RE_Storage_Array_Read);
7526 elsif Nam = TSS_Stream_Write
7527 and then Is_Available (RE_Storage_Array_Write)
7529 return RTE (RE_Storage_Array_Write);
7531 elsif Nam /= TSS_Stream_Input and then
7532 Nam /= TSS_Stream_Output and then
7533 Nam /= TSS_Stream_Read and then
7534 Nam /= TSS_Stream_Write
7536 raise Program_Error;
7539 -- Restriction No_Stream_Optimizations is not set, so we can go
7540 -- ahead and optimize using the block IO forms of the routines.
7543 if Nam = TSS_Stream_Input
7544 and then Is_Available (RE_Storage_Array_Input_Blk_IO)
7546 return RTE (RE_Storage_Array_Input_Blk_IO);
7548 elsif Nam = TSS_Stream_Output
7549 and then Is_Available (RE_Storage_Array_Output_Blk_IO)
7551 return RTE (RE_Storage_Array_Output_Blk_IO);
7553 elsif Nam = TSS_Stream_Read
7554 and then Is_Available (RE_Storage_Array_Read_Blk_IO)
7556 return RTE (RE_Storage_Array_Read_Blk_IO);
7558 elsif Nam = TSS_Stream_Write
7559 and then Is_Available (RE_Storage_Array_Write_Blk_IO)
7561 return RTE (RE_Storage_Array_Write_Blk_IO);
7563 elsif Nam /= TSS_Stream_Input and then
7564 Nam /= TSS_Stream_Output and then
7565 Nam /= TSS_Stream_Read and then
7566 Nam /= TSS_Stream_Write
7568 raise Program_Error;
7572 -- Stream_Element_Array as defined in package Ada.Streams
7574 elsif Is_RTE (Base_Typ, RE_Stream_Element_Array) then
7576 -- Case of No_Stream_Optimizations restriction active
7578 if Restriction_Active (No_Stream_Optimizations) then
7579 if Nam = TSS_Stream_Input
7580 and then Is_Available (RE_Stream_Element_Array_Input)
7582 return RTE (RE_Stream_Element_Array_Input);
7584 elsif Nam = TSS_Stream_Output
7585 and then Is_Available (RE_Stream_Element_Array_Output)
7587 return RTE (RE_Stream_Element_Array_Output);
7589 elsif Nam = TSS_Stream_Read
7590 and then Is_Available (RE_Stream_Element_Array_Read)
7592 return RTE (RE_Stream_Element_Array_Read);
7594 elsif Nam = TSS_Stream_Write
7595 and then Is_Available (RE_Stream_Element_Array_Write)
7597 return RTE (RE_Stream_Element_Array_Write);
7599 elsif Nam /= TSS_Stream_Input and then
7600 Nam /= TSS_Stream_Output and then
7601 Nam /= TSS_Stream_Read and then
7602 Nam /= TSS_Stream_Write
7604 raise Program_Error;
7607 -- Restriction No_Stream_Optimizations is not set, so we can go
7608 -- ahead and optimize using the block IO forms of the routines.
7611 if Nam = TSS_Stream_Input
7612 and then Is_Available (RE_Stream_Element_Array_Input_Blk_IO)
7614 return RTE (RE_Stream_Element_Array_Input_Blk_IO);
7616 elsif Nam = TSS_Stream_Output
7617 and then Is_Available (RE_Stream_Element_Array_Output_Blk_IO)
7619 return RTE (RE_Stream_Element_Array_Output_Blk_IO);
7621 elsif Nam = TSS_Stream_Read
7622 and then Is_Available (RE_Stream_Element_Array_Read_Blk_IO)
7624 return RTE (RE_Stream_Element_Array_Read_Blk_IO);
7626 elsif Nam = TSS_Stream_Write
7627 and then Is_Available (RE_Stream_Element_Array_Write_Blk_IO)
7629 return RTE (RE_Stream_Element_Array_Write_Blk_IO);
7631 elsif Nam /= TSS_Stream_Input and then
7632 Nam /= TSS_Stream_Output and then
7633 Nam /= TSS_Stream_Read and then
7634 Nam /= TSS_Stream_Write
7636 raise Program_Error;
7640 -- String as defined in package Ada
7642 elsif Base_Typ = Standard_String then
7644 -- Case of No_Stream_Optimizations restriction active
7646 if Restriction_Active (No_Stream_Optimizations) then
7647 if Nam = TSS_Stream_Input
7648 and then Is_Available (RE_String_Input)
7650 return RTE (RE_String_Input);
7652 elsif Nam = TSS_Stream_Output
7653 and then Is_Available (RE_String_Output)
7655 return RTE (RE_String_Output);
7657 elsif Nam = TSS_Stream_Read
7658 and then Is_Available (RE_String_Read)
7660 return RTE (RE_String_Read);
7662 elsif Nam = TSS_Stream_Write
7663 and then Is_Available (RE_String_Write)
7665 return RTE (RE_String_Write);
7667 elsif Nam /= TSS_Stream_Input and then
7668 Nam /= TSS_Stream_Output and then
7669 Nam /= TSS_Stream_Read and then
7670 Nam /= TSS_Stream_Write
7672 raise Program_Error;
7675 -- Restriction No_Stream_Optimizations is not set, so we can go
7676 -- ahead and optimize using the block IO forms of the routines.
7679 if Nam = TSS_Stream_Input
7680 and then Is_Available (RE_String_Input_Blk_IO)
7682 return RTE (RE_String_Input_Blk_IO);
7684 elsif Nam = TSS_Stream_Output
7685 and then Is_Available (RE_String_Output_Blk_IO)
7687 return RTE (RE_String_Output_Blk_IO);
7689 elsif Nam = TSS_Stream_Read
7690 and then Is_Available (RE_String_Read_Blk_IO)
7692 return RTE (RE_String_Read_Blk_IO);
7694 elsif Nam = TSS_Stream_Write
7695 and then Is_Available (RE_String_Write_Blk_IO)
7697 return RTE (RE_String_Write_Blk_IO);
7699 elsif Nam /= TSS_Stream_Input and then
7700 Nam /= TSS_Stream_Output and then
7701 Nam /= TSS_Stream_Read and then
7702 Nam /= TSS_Stream_Write
7704 raise Program_Error;
7708 -- Wide_String as defined in package Ada
7710 elsif Base_Typ = Standard_Wide_String then
7712 -- Case of No_Stream_Optimizations restriction active
7714 if Restriction_Active (No_Stream_Optimizations) then
7715 if Nam = TSS_Stream_Input
7716 and then Is_Available (RE_Wide_String_Input)
7718 return RTE (RE_Wide_String_Input);
7720 elsif Nam = TSS_Stream_Output
7721 and then Is_Available (RE_Wide_String_Output)
7723 return RTE (RE_Wide_String_Output);
7725 elsif Nam = TSS_Stream_Read
7726 and then Is_Available (RE_Wide_String_Read)
7728 return RTE (RE_Wide_String_Read);
7730 elsif Nam = TSS_Stream_Write
7731 and then Is_Available (RE_Wide_String_Write)
7733 return RTE (RE_Wide_String_Write);
7735 elsif Nam /= TSS_Stream_Input and then
7736 Nam /= TSS_Stream_Output and then
7737 Nam /= TSS_Stream_Read and then
7738 Nam /= TSS_Stream_Write
7740 raise Program_Error;
7743 -- Restriction No_Stream_Optimizations is not set, so we can go
7744 -- ahead and optimize using the block IO forms of the routines.
7747 if Nam = TSS_Stream_Input
7748 and then Is_Available (RE_Wide_String_Input_Blk_IO)
7750 return RTE (RE_Wide_String_Input_Blk_IO);
7752 elsif Nam = TSS_Stream_Output
7753 and then Is_Available (RE_Wide_String_Output_Blk_IO)
7755 return RTE (RE_Wide_String_Output_Blk_IO);
7757 elsif Nam = TSS_Stream_Read
7758 and then Is_Available (RE_Wide_String_Read_Blk_IO)
7760 return RTE (RE_Wide_String_Read_Blk_IO);
7762 elsif Nam = TSS_Stream_Write
7763 and then Is_Available (RE_Wide_String_Write_Blk_IO)
7765 return RTE (RE_Wide_String_Write_Blk_IO);
7767 elsif Nam /= TSS_Stream_Input and then
7768 Nam /= TSS_Stream_Output and then
7769 Nam /= TSS_Stream_Read and then
7770 Nam /= TSS_Stream_Write
7772 raise Program_Error;
7776 -- Wide_Wide_String as defined in package Ada
7778 elsif Base_Typ = Standard_Wide_Wide_String then
7780 -- Case of No_Stream_Optimizations restriction active
7782 if Restriction_Active (No_Stream_Optimizations) then
7783 if Nam = TSS_Stream_Input
7784 and then Is_Available (RE_Wide_Wide_String_Input)
7786 return RTE (RE_Wide_Wide_String_Input);
7788 elsif Nam = TSS_Stream_Output
7789 and then Is_Available (RE_Wide_Wide_String_Output)
7791 return RTE (RE_Wide_Wide_String_Output);
7793 elsif Nam = TSS_Stream_Read
7794 and then Is_Available (RE_Wide_Wide_String_Read)
7796 return RTE (RE_Wide_Wide_String_Read);
7798 elsif Nam = TSS_Stream_Write
7799 and then Is_Available (RE_Wide_Wide_String_Write)
7801 return RTE (RE_Wide_Wide_String_Write);
7803 elsif Nam /= TSS_Stream_Input and then
7804 Nam /= TSS_Stream_Output and then
7805 Nam /= TSS_Stream_Read and then
7806 Nam /= TSS_Stream_Write
7808 raise Program_Error;
7811 -- Restriction No_Stream_Optimizations is not set, so we can go
7812 -- ahead and optimize using the block IO forms of the routines.
7815 if Nam = TSS_Stream_Input
7816 and then Is_Available (RE_Wide_Wide_String_Input_Blk_IO)
7818 return RTE (RE_Wide_Wide_String_Input_Blk_IO);
7820 elsif Nam = TSS_Stream_Output
7821 and then Is_Available (RE_Wide_Wide_String_Output_Blk_IO)
7823 return RTE (RE_Wide_Wide_String_Output_Blk_IO);
7825 elsif Nam = TSS_Stream_Read
7826 and then Is_Available (RE_Wide_Wide_String_Read_Blk_IO)
7828 return RTE (RE_Wide_Wide_String_Read_Blk_IO);
7830 elsif Nam = TSS_Stream_Write
7831 and then Is_Available (RE_Wide_Wide_String_Write_Blk_IO)
7833 return RTE (RE_Wide_Wide_String_Write_Blk_IO);
7835 elsif Nam /= TSS_Stream_Input and then
7836 Nam /= TSS_Stream_Output and then
7837 Nam /= TSS_Stream_Read and then
7838 Nam /= TSS_Stream_Write
7840 raise Program_Error;
7846 if Is_Tagged_Type (Typ) and then Is_Derived_Type (Typ) then
7847 return Find_Prim_Op (Typ, Nam);
7849 return Find_Inherited_TSS (Typ, Nam);
7851 end Find_Stream_Subprogram;
7857 function Full_Base (T : Entity_Id) return Entity_Id is
7861 BT := Base_Type (T);
7863 if Is_Private_Type (BT)
7864 and then Present (Full_View (BT))
7866 BT := Full_View (BT);
7872 -----------------------
7873 -- Get_Index_Subtype --
7874 -----------------------
7876 function Get_Index_Subtype (N : Node_Id) return Node_Id is
7877 P_Type : Entity_Id := Etype (Prefix (N));
7882 if Is_Access_Type (P_Type) then
7883 P_Type := Designated_Type (P_Type);
7886 if No (Expressions (N)) then
7889 J := UI_To_Int (Expr_Value (First (Expressions (N))));
7892 Indx := First_Index (P_Type);
7898 return Etype (Indx);
7899 end Get_Index_Subtype;
7901 -------------------------------
7902 -- Get_Stream_Convert_Pragma --
7903 -------------------------------
7905 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id is
7910 -- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
7911 -- that a stream convert pragma for a tagged type is not inherited from
7912 -- its parent. Probably what is wrong here is that it is basically
7913 -- incorrect to consider a stream convert pragma to be a representation
7914 -- pragma at all ???
7916 N := First_Rep_Item (Implementation_Base_Type (T));
7917 while Present (N) loop
7918 if Nkind (N) = N_Pragma
7919 and then Pragma_Name (N) = Name_Stream_Convert
7921 -- For tagged types this pragma is not inherited, so we
7922 -- must verify that it is defined for the given type and
7926 Entity (Expression (First (Pragma_Argument_Associations (N))));
7928 if not Is_Tagged_Type (T)
7930 or else (Is_Private_Type (Typ) and then T = Full_View (Typ))
7940 end Get_Stream_Convert_Pragma;
7942 ---------------------------------
7943 -- Is_Constrained_Packed_Array --
7944 ---------------------------------
7946 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is
7947 Arr : Entity_Id := Typ;
7950 if Is_Access_Type (Arr) then
7951 Arr := Designated_Type (Arr);
7954 return Is_Array_Type (Arr)
7955 and then Is_Constrained (Arr)
7956 and then Present (Packed_Array_Impl_Type (Arr));
7957 end Is_Constrained_Packed_Array;
7959 ----------------------------------------
7960 -- Is_Inline_Floating_Point_Attribute --
7961 ----------------------------------------
7963 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean is
7964 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
7966 function Is_GCC_Target return Boolean;
7967 -- Return True if we are using a GCC target/back-end
7968 -- ??? Note: the implementation is kludgy/fragile
7974 function Is_GCC_Target return Boolean is
7976 return not CodePeer_Mode and then not AAMP_On_Target;
7979 -- Start of processing for Exp_Attr
7982 -- Machine and Model can be expanded by the GCC backend only
7984 if Id = Attribute_Machine or else Id = Attribute_Model then
7985 return Is_GCC_Target;
7987 -- Remaining cases handled by all back ends are Rounding and Truncation
7988 -- when appearing as the operand of a conversion to some integer type.
7990 elsif Nkind (Parent (N)) /= N_Type_Conversion
7991 or else not Is_Integer_Type (Etype (Parent (N)))
7996 -- Here we are in the integer conversion context
7998 -- Very probably we should also recognize the cases of Machine_Rounding
7999 -- and unbiased rounding in this conversion context, but the back end is
8000 -- not yet prepared to handle these cases ???
8002 return Id = Attribute_Rounding or else Id = Attribute_Truncation;
8003 end Is_Inline_Floating_Point_Attribute;