PR target/58115
[official-gcc.git] / gcc / ada / expander.adb
bloba037dd3790c52f255757c5da29e31fcf49dc5c9c
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- E X P A N D E R --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2013, Free Software Foundation, Inc. --
10 -- --
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. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Debug_A; use Debug_A;
28 with Exp_Aggr; use Exp_Aggr;
29 with Exp_SPARK; use Exp_SPARK;
30 with Exp_Attr; use Exp_Attr;
31 with Exp_Ch2; use Exp_Ch2;
32 with Exp_Ch3; use Exp_Ch3;
33 with Exp_Ch4; use Exp_Ch4;
34 with Exp_Ch5; use Exp_Ch5;
35 with Exp_Ch6; use Exp_Ch6;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch8; use Exp_Ch8;
38 with Exp_Ch9; use Exp_Ch9;
39 with Exp_Ch11; use Exp_Ch11;
40 with Exp_Ch12; use Exp_Ch12;
41 with Exp_Ch13; use Exp_Ch13;
42 with Exp_Prag; use Exp_Prag;
43 with Opt; use Opt;
44 with Rtsfind; use Rtsfind;
45 with Sem; use Sem;
46 with Sem_Ch8; use Sem_Ch8;
47 with Sem_Util; use Sem_Util;
48 with Sinfo; use Sinfo;
49 with Table;
51 package body Expander is
53 ----------------
54 -- Local Data --
55 ----------------
57 -- The following table is used to save values of the Expander_Active flag
58 -- when they are saved by Expander_Mode_Save_And_Set. We use an extendible
59 -- table (which is a bit of overkill) because it is easier than figuring
60 -- out a maximum value or bothering with range checks!
62 package Expander_Flags is new Table.Table (
63 Table_Component_Type => Boolean,
64 Table_Index_Type => Int,
65 Table_Low_Bound => 0,
66 Table_Initial => 32,
67 Table_Increment => 200,
68 Table_Name => "Expander_Flags");
70 ------------
71 -- Expand --
72 ------------
74 procedure Expand (N : Node_Id) is
75 begin
76 -- If we were analyzing a default expression (or other spec expression)
77 -- the Full_Analysis flag must be off. If we are in expansion mode then
78 -- we must be performing a full analysis. If we are analyzing a generic
79 -- then Expansion must be off.
81 pragma Assert
82 (not (Full_Analysis and then In_Spec_Expression)
83 and then (Full_Analysis or else not Expander_Active)
84 and then not (Inside_A_Generic and then Expander_Active));
86 -- There are three reasons for the Expander_Active flag to be false
88 -- The first is when are not generating code. In this mode the
89 -- Full_Analysis flag indicates whether we are performing a complete
90 -- analysis, in which case Full_Analysis = True or a pre-analysis in
91 -- which case Full_Analysis = False. See the spec of Sem for more
92 -- info on this.
94 -- The second reason for the Expander_Active flag to be False is that
95 -- we are performing a pre-analysis. During pre-analysis all expansion
96 -- activity is turned off to make sure nodes are semantically decorated
97 -- but no extra nodes are generated. This is for instance needed for
98 -- the first pass of aggregate semantic processing. Note that in this
99 -- case the Full_Analysis flag is set to False because the node will
100 -- subsequently be re-analyzed with expansion on (see the spec of sem).
102 -- Finally, expansion is turned off in a regular compilation if there
103 -- are serious errors. In that case there will be no further expansion,
104 -- but one cleanup action may be required: if a transient scope was
105 -- created (e.g. for a function that returns an unconstrained type) the
106 -- scope may still be on the stack, and must be removed explicitly,
107 -- given that the expansion actions that would normally process it will
108 -- not take place. This prevents cascaded errors due to stack mismatch.
110 if not Expander_Active then
111 Set_Analyzed (N, Full_Analysis);
113 if Serious_Errors_Detected > 0
114 and then Scope_Is_Transient
115 then
116 Scope_Stack.Table
117 (Scope_Stack.Last).Actions_To_Be_Wrapped_Before := No_List;
118 Scope_Stack.Table
119 (Scope_Stack.Last).Actions_To_Be_Wrapped_After := No_List;
121 Pop_Scope;
122 end if;
124 return;
126 else
127 Debug_A_Entry ("expanding ", N);
129 begin
130 -- In SPARK mode we only need a very limited subset of the usual
131 -- expansions. This limited subset is implemented in Expand_SPARK.
133 if SPARK_Mode then
134 Expand_SPARK (N);
136 -- Here for normal non-SPARK mode
138 else
139 -- Processing depends on node kind. For full details on the
140 -- expansion activity required in each case, see bodies of
141 -- corresponding expand routines.
143 case Nkind (N) is
145 when N_Abort_Statement =>
146 Expand_N_Abort_Statement (N);
148 when N_Accept_Statement =>
149 Expand_N_Accept_Statement (N);
151 when N_Aggregate =>
152 Expand_N_Aggregate (N);
154 when N_Allocator =>
155 Expand_N_Allocator (N);
157 when N_And_Then =>
158 Expand_N_And_Then (N);
160 when N_Assignment_Statement =>
161 Expand_N_Assignment_Statement (N);
163 when N_Asynchronous_Select =>
164 Expand_N_Asynchronous_Select (N);
166 when N_Attribute_Definition_Clause =>
167 Expand_N_Attribute_Definition_Clause (N);
169 when N_Attribute_Reference =>
170 Expand_N_Attribute_Reference (N);
172 when N_Block_Statement =>
173 Expand_N_Block_Statement (N);
175 when N_Case_Expression =>
176 Expand_N_Case_Expression (N);
178 when N_Case_Statement =>
179 Expand_N_Case_Statement (N);
181 when N_Conditional_Entry_Call =>
182 Expand_N_Conditional_Entry_Call (N);
184 when N_Delay_Relative_Statement =>
185 Expand_N_Delay_Relative_Statement (N);
187 when N_Delay_Until_Statement =>
188 Expand_N_Delay_Until_Statement (N);
190 when N_Entry_Body =>
191 Expand_N_Entry_Body (N);
193 when N_Entry_Call_Statement =>
194 Expand_N_Entry_Call_Statement (N);
196 when N_Entry_Declaration =>
197 Expand_N_Entry_Declaration (N);
199 when N_Exception_Declaration =>
200 Expand_N_Exception_Declaration (N);
202 when N_Exception_Renaming_Declaration =>
203 Expand_N_Exception_Renaming_Declaration (N);
205 when N_Exit_Statement =>
206 Expand_N_Exit_Statement (N);
208 when N_Expanded_Name =>
209 Expand_N_Expanded_Name (N);
211 when N_Explicit_Dereference =>
212 Expand_N_Explicit_Dereference (N);
214 when N_Expression_With_Actions =>
215 Expand_N_Expression_With_Actions (N);
217 when N_Extended_Return_Statement =>
218 Expand_N_Extended_Return_Statement (N);
220 when N_Extension_Aggregate =>
221 Expand_N_Extension_Aggregate (N);
223 when N_Free_Statement =>
224 Expand_N_Free_Statement (N);
226 when N_Freeze_Entity =>
227 Expand_N_Freeze_Entity (N);
229 when N_Full_Type_Declaration =>
230 Expand_N_Full_Type_Declaration (N);
232 when N_Function_Call =>
233 Expand_N_Function_Call (N);
235 when N_Generic_Instantiation =>
236 Expand_N_Generic_Instantiation (N);
238 when N_Goto_Statement =>
239 Expand_N_Goto_Statement (N);
241 when N_Handled_Sequence_Of_Statements =>
242 Expand_N_Handled_Sequence_Of_Statements (N);
244 when N_Identifier =>
245 Expand_N_Identifier (N);
247 when N_If_Expression =>
248 Expand_N_If_Expression (N);
250 when N_Indexed_Component =>
251 Expand_N_Indexed_Component (N);
253 when N_If_Statement =>
254 Expand_N_If_Statement (N);
256 when N_In =>
257 Expand_N_In (N);
259 when N_Loop_Statement =>
260 Expand_N_Loop_Statement (N);
262 when N_Not_In =>
263 Expand_N_Not_In (N);
265 when N_Null =>
266 Expand_N_Null (N);
268 when N_Object_Declaration =>
269 Expand_N_Object_Declaration (N);
271 when N_Object_Renaming_Declaration =>
272 Expand_N_Object_Renaming_Declaration (N);
274 when N_Op_Add =>
275 Expand_N_Op_Add (N);
277 when N_Op_Abs =>
278 Expand_N_Op_Abs (N);
280 when N_Op_And =>
281 Expand_N_Op_And (N);
283 when N_Op_Concat =>
284 Expand_N_Op_Concat (N);
286 when N_Op_Divide =>
287 Expand_N_Op_Divide (N);
289 when N_Op_Eq =>
290 Expand_N_Op_Eq (N);
292 when N_Op_Expon =>
293 Expand_N_Op_Expon (N);
295 when N_Op_Ge =>
296 Expand_N_Op_Ge (N);
298 when N_Op_Gt =>
299 Expand_N_Op_Gt (N);
301 when N_Op_Le =>
302 Expand_N_Op_Le (N);
304 when N_Op_Lt =>
305 Expand_N_Op_Lt (N);
307 when N_Op_Minus =>
308 Expand_N_Op_Minus (N);
310 when N_Op_Mod =>
311 Expand_N_Op_Mod (N);
313 when N_Op_Multiply =>
314 Expand_N_Op_Multiply (N);
316 when N_Op_Ne =>
317 Expand_N_Op_Ne (N);
319 when N_Op_Not =>
320 Expand_N_Op_Not (N);
322 when N_Op_Or =>
323 Expand_N_Op_Or (N);
325 when N_Op_Plus =>
326 Expand_N_Op_Plus (N);
328 when N_Op_Rem =>
329 Expand_N_Op_Rem (N);
331 when N_Op_Rotate_Left =>
332 Expand_N_Op_Rotate_Left (N);
334 when N_Op_Rotate_Right =>
335 Expand_N_Op_Rotate_Right (N);
337 when N_Op_Shift_Left =>
338 Expand_N_Op_Shift_Left (N);
340 when N_Op_Shift_Right =>
341 Expand_N_Op_Shift_Right (N);
343 when N_Op_Shift_Right_Arithmetic =>
344 Expand_N_Op_Shift_Right_Arithmetic (N);
346 when N_Op_Subtract =>
347 Expand_N_Op_Subtract (N);
349 when N_Op_Xor =>
350 Expand_N_Op_Xor (N);
352 when N_Or_Else =>
353 Expand_N_Or_Else (N);
355 when N_Package_Body =>
356 Expand_N_Package_Body (N);
358 when N_Package_Declaration =>
359 Expand_N_Package_Declaration (N);
361 when N_Package_Renaming_Declaration =>
362 Expand_N_Package_Renaming_Declaration (N);
364 when N_Subprogram_Renaming_Declaration =>
365 Expand_N_Subprogram_Renaming_Declaration (N);
367 when N_Pragma =>
368 Expand_N_Pragma (N);
370 when N_Procedure_Call_Statement =>
371 Expand_N_Procedure_Call_Statement (N);
373 when N_Protected_Type_Declaration =>
374 Expand_N_Protected_Type_Declaration (N);
376 when N_Protected_Body =>
377 Expand_N_Protected_Body (N);
379 when N_Qualified_Expression =>
380 Expand_N_Qualified_Expression (N);
382 when N_Quantified_Expression =>
383 Expand_N_Quantified_Expression (N);
385 when N_Raise_Statement =>
386 Expand_N_Raise_Statement (N);
388 when N_Raise_Constraint_Error =>
389 Expand_N_Raise_Constraint_Error (N);
391 when N_Raise_Expression =>
392 Expand_N_Raise_Expression (N);
394 when N_Raise_Program_Error =>
395 Expand_N_Raise_Program_Error (N);
397 when N_Raise_Storage_Error =>
398 Expand_N_Raise_Storage_Error (N);
400 when N_Real_Literal =>
401 Expand_N_Real_Literal (N);
403 when N_Record_Representation_Clause =>
404 Expand_N_Record_Representation_Clause (N);
406 when N_Requeue_Statement =>
407 Expand_N_Requeue_Statement (N);
409 when N_Simple_Return_Statement =>
410 Expand_N_Simple_Return_Statement (N);
412 when N_Selected_Component =>
413 Expand_N_Selected_Component (N);
415 when N_Selective_Accept =>
416 Expand_N_Selective_Accept (N);
418 when N_Single_Task_Declaration =>
419 Expand_N_Single_Task_Declaration (N);
421 when N_Slice =>
422 Expand_N_Slice (N);
424 when N_Subtype_Indication =>
425 Expand_N_Subtype_Indication (N);
427 when N_Subprogram_Body =>
428 Expand_N_Subprogram_Body (N);
430 when N_Subprogram_Body_Stub =>
431 Expand_N_Subprogram_Body_Stub (N);
433 when N_Subprogram_Declaration =>
434 Expand_N_Subprogram_Declaration (N);
436 when N_Subprogram_Info =>
437 Expand_N_Subprogram_Info (N);
439 when N_Task_Body =>
440 Expand_N_Task_Body (N);
442 when N_Task_Type_Declaration =>
443 Expand_N_Task_Type_Declaration (N);
445 when N_Timed_Entry_Call =>
446 Expand_N_Timed_Entry_Call (N);
448 when N_Type_Conversion =>
449 Expand_N_Type_Conversion (N);
451 when N_Unchecked_Expression =>
452 Expand_N_Unchecked_Expression (N);
454 when N_Unchecked_Type_Conversion =>
455 Expand_N_Unchecked_Type_Conversion (N);
457 when N_Variant_Part =>
458 Expand_N_Variant_Part (N);
460 -- For all other node kinds, no expansion activity required
462 when others =>
463 null;
465 end case;
466 end if;
468 exception
469 when RE_Not_Available =>
470 return;
471 end;
473 -- Set result as analyzed and then do a possible transient wrap. The
474 -- transient wrap must be done after the Analyzed flag is set on, so
475 -- that we do not get a recursive attempt to expand the node N.
477 Set_Analyzed (N);
479 -- Deal with transient scopes
481 if Scope_Is_Transient and then N = Node_To_Be_Wrapped then
482 case Nkind (N) is
483 when N_Statement_Other_Than_Procedure_Call |
484 N_Procedure_Call_Statement =>
485 Wrap_Transient_Statement (N);
487 when N_Object_Declaration |
488 N_Object_Renaming_Declaration |
489 N_Subtype_Declaration =>
490 Wrap_Transient_Declaration (N);
492 when others => Wrap_Transient_Expression (N);
493 end case;
494 end if;
496 Debug_A_Exit ("expanding ", N, " (done)");
497 end if;
498 end Expand;
500 ---------------------------
501 -- Expander_Mode_Restore --
502 ---------------------------
504 procedure Expander_Mode_Restore is
505 begin
506 -- Not active (has no effect) in ASIS mode (see comments in spec of
507 -- Expander_Mode_Save_And_Set).
509 if ASIS_Mode then
510 return;
511 end if;
513 -- Otherwise restore the flag
515 Expander_Active := Expander_Flags.Table (Expander_Flags.Last);
516 Expander_Flags.Decrement_Last;
518 -- Keep expander off if serious errors detected. In this case we do not
519 -- need expansion, and continued expansion may cause cascaded errors or
520 -- compiler bombs.
522 if Serious_Errors_Detected /= 0 then
523 Expander_Active := False;
524 end if;
525 end Expander_Mode_Restore;
527 --------------------------------
528 -- Expander_Mode_Save_And_Set --
529 --------------------------------
531 procedure Expander_Mode_Save_And_Set (Status : Boolean) is
532 begin
533 -- Not active (has no effect) in ASIS mode (see comments in spec of
534 -- Expander_Mode_Save_And_Set).
536 if ASIS_Mode then
537 return;
538 end if;
540 -- Otherwise save and set the flag
542 Expander_Flags.Increment_Last;
543 Expander_Flags.Table (Expander_Flags.Last) := Expander_Active;
544 Expander_Active := Status;
545 end Expander_Mode_Save_And_Set;
547 end Expander;