1 /* Perform the semantic phase of parsing, i.e., the process of
2 building tree structure, checking semantic consistency, and
3 building RTL. These routines are used both during actual parsing
4 and during the instantiation of template functions.
5
6 Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
7 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc.
8 Written by Mark Mitchell (mmitchell@usa.net) based on code found
9 formerly in parse.y and pt.c.
10
11 This file is part of GCC.
12
13 GCC is free software; you can redistribute it and/or modify it
14 under the terms of the GNU General Public License as published by
15 the Free Software Foundation; either version 3, or (at your option)
16 any later version.
17
18 GCC is distributed in the hope that it will be useful, but
19 WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 General Public License for more details.
22
23 You should have received a copy of the GNU General Public License
24 along with GCC; see the file COPYING3. If not see
25 <http://www.gnu.org/licenses/>. */
26
27 #include "config.h"
28 #include "system.h"
29 #include "coretypes.h"
30 #include "tm.h"
31 #include "tree.h"
32 #include "cp-tree.h"
33 #include "c-family/c-common.h"
34 #include "c-family/c-objc.h"
35 #include "tree-inline.h"
36 #include "intl.h"
37 #include "toplev.h"
38 #include "flags.h"
39 #include "output.h"
40 #include "timevar.h"
41 #include "diagnostic.h"
42 #include "cgraph.h"
43 #include "tree-iterator.h"
44 #include "vec.h"
45 #include "target.h"
46 #include "gimple.h"
47 #include "bitmap.h"
48
49 /* There routines provide a modular interface to perform many parsing
50 operations. They may therefore be used during actual parsing, or
51 during template instantiation, which may be regarded as a
52 degenerate form of parsing. */
53
54 static tree maybe_convert_cond (tree);
55 static tree finalize_nrv_r (tree *, int *, void *);
56 static tree capture_decltype (tree);
57
58
59 /* Deferred Access Checking Overview
60 ---------------------------------
61
62 Most C++ expressions and declarations require access checking
63 to be performed during parsing. However, in several cases,
64 this has to be treated differently.
65
66 For member declarations, access checking has to be deferred
67 until more information about the declaration is known. For
68 example:
69
70 class A {
71 typedef int X;
72 public:
73 X f();
74 };
75
76 A::X A::f();
77 A::X g();
78
79 When we are parsing the function return type `A::X', we don't
80 really know if this is allowed until we parse the function name.
81
82 Furthermore, some contexts require that access checking is
83 never performed at all. These include class heads, and template
84 instantiations.
85
86 Typical use of access checking functions is described here:
87
88 1. When we enter a context that requires certain access checking
89 mode, the function `push_deferring_access_checks' is called with
90 DEFERRING argument specifying the desired mode. Access checking
91 may be performed immediately (dk_no_deferred), deferred
92 (dk_deferred), or not performed (dk_no_check).
93
94 2. When a declaration such as a type, or a variable, is encountered,
95 the function `perform_or_defer_access_check' is called. It
96 maintains a VEC of all deferred checks.
97
98 3. The global `current_class_type' or `current_function_decl' is then
99 setup by the parser. `enforce_access' relies on these information
100 to check access.
101
102 4. Upon exiting the context mentioned in step 1,
103 `perform_deferred_access_checks' is called to check all declaration
104 stored in the VEC. `pop_deferring_access_checks' is then
105 called to restore the previous access checking mode.
106
107 In case of parsing error, we simply call `pop_deferring_access_checks'
108 without `perform_deferred_access_checks'. */
109
110 typedef struct GTY(()) deferred_access {
111 /* A VEC representing name-lookups for which we have deferred
112 checking access controls. We cannot check the accessibility of
113 names used in a decl-specifier-seq until we know what is being
114 declared because code like:
115
116 class A {
117 class B {};
118 B* f();
119 }
120
121 A::B* A::f() { return 0; }
122
123 is valid, even though `A::B' is not generally accessible. */
124 VEC (deferred_access_check,gc)* GTY(()) deferred_access_checks;
125
126 /* The current mode of access checks. */
127 enum deferring_kind deferring_access_checks_kind;
128
129 } deferred_access;
130 DEF_VEC_O (deferred_access);
131 DEF_VEC_ALLOC_O (deferred_access,gc);
132
133 /* Data for deferred access checking. */
134 static GTY(()) VEC(deferred_access,gc) *deferred_access_stack;
135 static GTY(()) unsigned deferred_access_no_check;
136
137 /* Save the current deferred access states and start deferred
138 access checking iff DEFER_P is true. */
139
140 void
push_deferring_access_checks(deferring_kind deferring)141 push_deferring_access_checks (deferring_kind deferring)
142 {
143 /* For context like template instantiation, access checking
144 disabling applies to all nested context. */
145 if (deferred_access_no_check || deferring == dk_no_check)
146 deferred_access_no_check++;
147 else
148 {
149 deferred_access *ptr;
150
151 ptr = VEC_safe_push (deferred_access, gc, deferred_access_stack, NULL);
152 ptr->deferred_access_checks = NULL;
153 ptr->deferring_access_checks_kind = deferring;
154 }
155 }
156
157 /* Resume deferring access checks again after we stopped doing
158 this previously. */
159
160 void
resume_deferring_access_checks(void)161 resume_deferring_access_checks (void)
162 {
163 if (!deferred_access_no_check)
164 VEC_last (deferred_access, deferred_access_stack)
165 ->deferring_access_checks_kind = dk_deferred;
166 }
167
168 /* Stop deferring access checks. */
169
170 void
stop_deferring_access_checks(void)171 stop_deferring_access_checks (void)
172 {
173 if (!deferred_access_no_check)
174 VEC_last (deferred_access, deferred_access_stack)
175 ->deferring_access_checks_kind = dk_no_deferred;
176 }
177
178 /* Discard the current deferred access checks and restore the
179 previous states. */
180
181 void
pop_deferring_access_checks(void)182 pop_deferring_access_checks (void)
183 {
184 if (deferred_access_no_check)
185 deferred_access_no_check--;
186 else
187 VEC_pop (deferred_access, deferred_access_stack);
188 }
189
190 /* Returns a TREE_LIST representing the deferred checks.
191 The TREE_PURPOSE of each node is the type through which the
192 access occurred; the TREE_VALUE is the declaration named.
193 */
194
VEC(deferred_access_check,gc)195 VEC (deferred_access_check,gc)*
196 get_deferred_access_checks (void)
197 {
198 if (deferred_access_no_check)
199 return NULL;
200 else
201 return (VEC_last (deferred_access, deferred_access_stack)
202 ->deferred_access_checks);
203 }
204
205 /* Take current deferred checks and combine with the
206 previous states if we also defer checks previously.
207 Otherwise perform checks now. */
208
209 void
pop_to_parent_deferring_access_checks(void)210 pop_to_parent_deferring_access_checks (void)
211 {
212 if (deferred_access_no_check)
213 deferred_access_no_check--;
214 else
215 {
216 VEC (deferred_access_check,gc) *checks;
217 deferred_access *ptr;
218
219 checks = (VEC_last (deferred_access, deferred_access_stack)
220 ->deferred_access_checks);
221
222 VEC_pop (deferred_access, deferred_access_stack);
223 ptr = VEC_last (deferred_access, deferred_access_stack);
224 if (ptr->deferring_access_checks_kind == dk_no_deferred)
225 {
226 /* Check access. */
227 perform_access_checks (checks);
228 }
229 else
230 {
231 /* Merge with parent. */
232 int i, j;
233 deferred_access_check *chk, *probe;
234
235 FOR_EACH_VEC_ELT (deferred_access_check, checks, i, chk)
236 {
237 FOR_EACH_VEC_ELT (deferred_access_check,
238 ptr->deferred_access_checks, j, probe)
239 {
240 if (probe->binfo == chk->binfo &&
241 probe->decl == chk->decl &&
242 probe->diag_decl == chk->diag_decl)
243 goto found;
244 }
245 /* Insert into parent's checks. */
246 VEC_safe_push (deferred_access_check, gc,
247 ptr->deferred_access_checks, chk);
248 found:;
249 }
250 }
251 }
252 }
253
254 /* Perform the access checks in CHECKS. The TREE_PURPOSE of each node
255 is the BINFO indicating the qualifying scope used to access the
256 DECL node stored in the TREE_VALUE of the node. */
257
258 void
perform_access_checks(VEC (deferred_access_check,gc)* checks)259 perform_access_checks (VEC (deferred_access_check,gc)* checks)
260 {
261 int i;
262 deferred_access_check *chk;
263
264 if (!checks)
265 return;
266
267 FOR_EACH_VEC_ELT (deferred_access_check, checks, i, chk)
268 enforce_access (chk->binfo, chk->decl, chk->diag_decl);
269 }
270
271 /* Perform the deferred access checks.
272
273 After performing the checks, we still have to keep the list
274 `deferred_access_stack->deferred_access_checks' since we may want
275 to check access for them again later in a different context.
276 For example:
277
278 class A {
279 typedef int X;
280 static X a;
281 };
282 A::X A::a, x; // No error for `A::a', error for `x'
283
284 We have to perform deferred access of `A::X', first with `A::a',
285 next with `x'. */
286
287 void
perform_deferred_access_checks(void)288 perform_deferred_access_checks (void)
289 {
290 perform_access_checks (get_deferred_access_checks ());
291 }
292
293 /* Defer checking the accessibility of DECL, when looked up in
294 BINFO. DIAG_DECL is the declaration to use to print diagnostics. */
295
296 void
perform_or_defer_access_check(tree binfo,tree decl,tree diag_decl)297 perform_or_defer_access_check (tree binfo, tree decl, tree diag_decl)
298 {
299 int i;
300 deferred_access *ptr;
301 deferred_access_check *chk;
302 deferred_access_check *new_access;
303
304
305 /* Exit if we are in a context that no access checking is performed.
306 */
307 if (deferred_access_no_check)
308 return;
309
310 gcc_assert (TREE_CODE (binfo) == TREE_BINFO);
311
312 ptr = VEC_last (deferred_access, deferred_access_stack);
313
314 /* If we are not supposed to defer access checks, just check now. */
315 if (ptr->deferring_access_checks_kind == dk_no_deferred)
316 {
317 enforce_access (binfo, decl, diag_decl);
318 return;
319 }
320
321 /* See if we are already going to perform this check. */
322 FOR_EACH_VEC_ELT (deferred_access_check,
323 ptr->deferred_access_checks, i, chk)
324 {
325 if (chk->decl == decl && chk->binfo == binfo &&
326 chk->diag_decl == diag_decl)
327 {
328 return;
329 }
330 }
331 /* If not, record the check. */
332 new_access =
333 VEC_safe_push (deferred_access_check, gc,
334 ptr->deferred_access_checks, 0);
335 new_access->binfo = binfo;
336 new_access->decl = decl;
337 new_access->diag_decl = diag_decl;
338 }
339
340 /* Used by build_over_call in LOOKUP_SPECULATIVE mode: return whether DECL
341 is accessible in BINFO, and possibly complain if not. If we're not
342 checking access, everything is accessible. */
343
344 bool
speculative_access_check(tree binfo,tree decl,tree diag_decl,bool complain)345 speculative_access_check (tree binfo, tree decl, tree diag_decl,
346 bool complain)
347 {
348 if (deferred_access_no_check)
349 return true;
350
351 /* If we're checking for implicit delete, we don't want access
352 control errors. */
353 if (!accessible_p (binfo, decl, true))
354 {
355 /* Unless we're under maybe_explain_implicit_delete. */
356 if (complain)
357 enforce_access (binfo, decl, diag_decl);
358 return false;
359 }
360
361 return true;
362 }
363
364 /* Returns nonzero if the current statement is a full expression,
365 i.e. temporaries created during that statement should be destroyed
366 at the end of the statement. */
367
368 int
stmts_are_full_exprs_p(void)369 stmts_are_full_exprs_p (void)
370 {
371 return current_stmt_tree ()->stmts_are_full_exprs_p;
372 }
373
374 /* T is a statement. Add it to the statement-tree. This is the C++
375 version. The C/ObjC frontends have a slightly different version of
376 this function. */
377
378 tree
add_stmt(tree t)379 add_stmt (tree t)
380 {
381 enum tree_code code = TREE_CODE (t);
382
383 if (EXPR_P (t) && code != LABEL_EXPR)
384 {
385 if (!EXPR_HAS_LOCATION (t))
386 SET_EXPR_LOCATION (t, input_location);
387
388 /* When we expand a statement-tree, we must know whether or not the
389 statements are full-expressions. We record that fact here. */
390 STMT_IS_FULL_EXPR_P (t) = stmts_are_full_exprs_p ();
391 }
392
393 /* Add T to the statement-tree. Non-side-effect statements need to be
394 recorded during statement expressions. */
395 gcc_checking_assert (!VEC_empty (tree, stmt_list_stack));
396 append_to_statement_list_force (t, &cur_stmt_list);
397
398 return t;
399 }
400
401 /* Returns the stmt_tree to which statements are currently being added. */
402
403 stmt_tree
current_stmt_tree(void)404 current_stmt_tree (void)
405 {
406 return (cfun
407 ? &cfun->language->base.x_stmt_tree
408 : &scope_chain->x_stmt_tree);
409 }
410
411 /* If statements are full expressions, wrap STMT in a CLEANUP_POINT_EXPR. */
412
413 static tree
maybe_cleanup_point_expr(tree expr)414 maybe_cleanup_point_expr (tree expr)
415 {
416 if (!processing_template_decl && stmts_are_full_exprs_p ())
417 expr = fold_build_cleanup_point_expr (TREE_TYPE (expr), expr);
418 return expr;
419 }
420
421 /* Like maybe_cleanup_point_expr except have the type of the new expression be
422 void so we don't need to create a temporary variable to hold the inner
423 expression. The reason why we do this is because the original type might be
424 an aggregate and we cannot create a temporary variable for that type. */
425
426 tree
maybe_cleanup_point_expr_void(tree expr)427 maybe_cleanup_point_expr_void (tree expr)
428 {
429 if (!processing_template_decl && stmts_are_full_exprs_p ())
430 expr = fold_build_cleanup_point_expr (void_type_node, expr);
431 return expr;
432 }
433
434
435
436 /* Create a declaration statement for the declaration given by the DECL. */
437
438 void
add_decl_expr(tree decl)439 add_decl_expr (tree decl)
440 {
441 tree r = build_stmt (input_location, DECL_EXPR, decl);
442 if (DECL_INITIAL (decl)
443 || (DECL_SIZE (decl) && TREE_SIDE_EFFECTS (DECL_SIZE (decl))))
444 r = maybe_cleanup_point_expr_void (r);
445 add_stmt (r);
446 }
447
448 /* Finish a scope. */
449
450 tree
do_poplevel(tree stmt_list)451 do_poplevel (tree stmt_list)
452 {
453 tree block = NULL;
454
455 if (stmts_are_full_exprs_p ())
456 block = poplevel (kept_level_p (), 1, 0);
457
458 stmt_list = pop_stmt_list (stmt_list);
459
460 if (!processing_template_decl)
461 {
462 stmt_list = c_build_bind_expr (input_location, block, stmt_list);
463 /* ??? See c_end_compound_stmt re statement expressions. */
464 }
465
466 return stmt_list;
467 }
468
469 /* Begin a new scope. */
470
471 static tree
do_pushlevel(scope_kind sk)472 do_pushlevel (scope_kind sk)
473 {
474 tree ret = push_stmt_list ();
475 if (stmts_are_full_exprs_p ())
476 begin_scope (sk, NULL);
477 return ret;
478 }
479
480 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
481 when the current scope is exited. EH_ONLY is true when this is not
482 meant to apply to normal control flow transfer. */
483
484 void
push_cleanup(tree decl,tree cleanup,bool eh_only)485 push_cleanup (tree decl, tree cleanup, bool eh_only)
486 {
487 tree stmt = build_stmt (input_location, CLEANUP_STMT, NULL, cleanup, decl);
488 CLEANUP_EH_ONLY (stmt) = eh_only;
489 add_stmt (stmt);
490 CLEANUP_BODY (stmt) = push_stmt_list ();
491 }
492
493 /* Begin a conditional that might contain a declaration. When generating
494 normal code, we want the declaration to appear before the statement
495 containing the conditional. When generating template code, we want the
496 conditional to be rendered as the raw DECL_EXPR. */
497
498 static void
begin_cond(tree * cond_p)499 begin_cond (tree *cond_p)
500 {
501 if (processing_template_decl)
502 *cond_p = push_stmt_list ();
503 }
504
505 /* Finish such a conditional. */
506
507 static void
finish_cond(tree * cond_p,tree expr)508 finish_cond (tree *cond_p, tree expr)
509 {
510 if (processing_template_decl)
511 {
512 tree cond = pop_stmt_list (*cond_p);
513 if (TREE_CODE (cond) == DECL_EXPR)
514 expr = cond;
515
516 if (check_for_bare_parameter_packs (expr))
517 *cond_p = error_mark_node;
518 }
519 *cond_p = expr;
520 }
521
522 /* If *COND_P specifies a conditional with a declaration, transform the
523 loop such that
524 while (A x = 42) { }
525 for (; A x = 42;) { }
526 becomes
527 while (true) { A x = 42; if (!x) break; }
528 for (;;) { A x = 42; if (!x) break; }
529 The statement list for BODY will be empty if the conditional did
530 not declare anything. */
531
532 static void
simplify_loop_decl_cond(tree * cond_p,tree body)533 simplify_loop_decl_cond (tree *cond_p, tree body)
534 {
535 tree cond, if_stmt;
536
537 if (!TREE_SIDE_EFFECTS (body))
538 return;
539
540 cond = *cond_p;
541 *cond_p = boolean_true_node;
542
543 if_stmt = begin_if_stmt ();
544 cond = cp_build_unary_op (TRUTH_NOT_EXPR, cond, 0, tf_warning_or_error);
545 finish_if_stmt_cond (cond, if_stmt);
546 finish_break_stmt ();
547 finish_then_clause (if_stmt);
548 finish_if_stmt (if_stmt);
549 }
550
551 /* Finish a goto-statement. */
552
553 tree
finish_goto_stmt(tree destination)554 finish_goto_stmt (tree destination)
555 {
556 if (TREE_CODE (destination) == IDENTIFIER_NODE)
557 destination = lookup_label (destination);
558
559 /* We warn about unused labels with -Wunused. That means we have to
560 mark the used labels as used. */
561 if (TREE_CODE (destination) == LABEL_DECL)
562 TREE_USED (destination) = 1;
563 else
564 {
565 destination = mark_rvalue_use (destination);
566 if (!processing_template_decl)
567 {
568 destination = cp_convert (ptr_type_node, destination);
569 if (error_operand_p (destination))
570 return NULL_TREE;
571 }
572 }
573
574 check_goto (destination);
575
576 return add_stmt (build_stmt (input_location, GOTO_EXPR, destination));
577 }
578
579 /* COND is the condition-expression for an if, while, etc.,
580 statement. Convert it to a boolean value, if appropriate.
581 In addition, verify sequence points if -Wsequence-point is enabled. */
582
583 static tree
maybe_convert_cond(tree cond)584 maybe_convert_cond (tree cond)
585 {
586 /* Empty conditions remain empty. */
587 if (!cond)
588 return NULL_TREE;
589
590 /* Wait until we instantiate templates before doing conversion. */
591 if (processing_template_decl)
592 return cond;
593
594 if (warn_sequence_point)
595 verify_sequence_points (cond);
596
597 /* Do the conversion. */
598 cond = convert_from_reference (cond);
599
600 if (TREE_CODE (cond) == MODIFY_EXPR
601 && !TREE_NO_WARNING (cond)
602 && warn_parentheses)
603 {
604 warning (OPT_Wparentheses,
605 "suggest parentheses around assignment used as truth value");
606 TREE_NO_WARNING (cond) = 1;
607 }
608
609 return condition_conversion (cond);
610 }
611
612 /* Finish an expression-statement, whose EXPRESSION is as indicated. */
613
614 tree
finish_expr_stmt(tree expr)615 finish_expr_stmt (tree expr)
616 {
617 tree r = NULL_TREE;
618
619 if (expr != NULL_TREE)
620 {
621 if (!processing_template_decl)
622 {
623 if (warn_sequence_point)
624 verify_sequence_points (expr);
625 expr = convert_to_void (expr, ICV_STATEMENT, tf_warning_or_error);
626 }
627 else if (!type_dependent_expression_p (expr))
628 convert_to_void (build_non_dependent_expr (expr), ICV_STATEMENT,
629 tf_warning_or_error);
630
631 if (check_for_bare_parameter_packs (expr))
632 expr = error_mark_node;
633
634 /* Simplification of inner statement expressions, compound exprs,
635 etc can result in us already having an EXPR_STMT. */
636 if (TREE_CODE (expr) != CLEANUP_POINT_EXPR)
637 {
638 if (TREE_CODE (expr) != EXPR_STMT)
639 expr = build_stmt (input_location, EXPR_STMT, expr);
640 expr = maybe_cleanup_point_expr_void (expr);
641 }
642
643 r = add_stmt (expr);
644 }
645
646 finish_stmt ();
647
648 return r;
649 }
650
651
652 /* Begin an if-statement. Returns a newly created IF_STMT if
653 appropriate. */
654
655 tree
begin_if_stmt(void)656 begin_if_stmt (void)
657 {
658 tree r, scope;
659 scope = do_pushlevel (sk_cond);
660 r = build_stmt (input_location, IF_STMT, NULL_TREE,
661 NULL_TREE, NULL_TREE, scope);
662 begin_cond (&IF_COND (r));
663 return r;
664 }
665
666 /* Process the COND of an if-statement, which may be given by
667 IF_STMT. */
668
669 void
finish_if_stmt_cond(tree cond,tree if_stmt)670 finish_if_stmt_cond (tree cond, tree if_stmt)
671 {
672 finish_cond (&IF_COND (if_stmt), maybe_convert_cond (cond));
673 add_stmt (if_stmt);
674 THEN_CLAUSE (if_stmt) = push_stmt_list ();
675 }
676
677 /* Finish the then-clause of an if-statement, which may be given by
678 IF_STMT. */
679
680 tree
finish_then_clause(tree if_stmt)681 finish_then_clause (tree if_stmt)
682 {
683 THEN_CLAUSE (if_stmt) = pop_stmt_list (THEN_CLAUSE (if_stmt));
684 return if_stmt;
685 }
686
687 /* Begin the else-clause of an if-statement. */
688
689 void
begin_else_clause(tree if_stmt)690 begin_else_clause (tree if_stmt)
691 {
692 ELSE_CLAUSE (if_stmt) = push_stmt_list ();
693 }
694
695 /* Finish the else-clause of an if-statement, which may be given by
696 IF_STMT. */
697
698 void
finish_else_clause(tree if_stmt)699 finish_else_clause (tree if_stmt)
700 {
701 ELSE_CLAUSE (if_stmt) = pop_stmt_list (ELSE_CLAUSE (if_stmt));
702 }
703
704 /* Finish an if-statement. */
705
706 void
finish_if_stmt(tree if_stmt)707 finish_if_stmt (tree if_stmt)
708 {
709 tree scope = IF_SCOPE (if_stmt);
710 IF_SCOPE (if_stmt) = NULL;
711 add_stmt (do_poplevel (scope));
712 finish_stmt ();
713 }
714
715 /* Begin a while-statement. Returns a newly created WHILE_STMT if
716 appropriate. */
717
718 tree
begin_while_stmt(void)719 begin_while_stmt (void)
720 {
721 tree r;
722 r = build_stmt (input_location, WHILE_STMT, NULL_TREE, NULL_TREE);
723 add_stmt (r);
724 WHILE_BODY (r) = do_pushlevel (sk_block);
725 begin_cond (&WHILE_COND (r));
726 return r;
727 }
728
729 /* Process the COND of a while-statement, which may be given by
730 WHILE_STMT. */
731
732 void
finish_while_stmt_cond(tree cond,tree while_stmt)733 finish_while_stmt_cond (tree cond, tree while_stmt)
734 {
735 finish_cond (&WHILE_COND (while_stmt), maybe_convert_cond (cond));
736 simplify_loop_decl_cond (&WHILE_COND (while_stmt), WHILE_BODY (while_stmt));
737 }
738
739 /* Finish a while-statement, which may be given by WHILE_STMT. */
740
741 void
finish_while_stmt(tree while_stmt)742 finish_while_stmt (tree while_stmt)
743 {
744 WHILE_BODY (while_stmt) = do_poplevel (WHILE_BODY (while_stmt));
745 finish_stmt ();
746 }
747
748 /* Begin a do-statement. Returns a newly created DO_STMT if
749 appropriate. */
750
751 tree
begin_do_stmt(void)752 begin_do_stmt (void)
753 {
754 tree r = build_stmt (input_location, DO_STMT, NULL_TREE, NULL_TREE);
755 add_stmt (r);
756 DO_BODY (r) = push_stmt_list ();
757 return r;
758 }
759
760 /* Finish the body of a do-statement, which may be given by DO_STMT. */
761
762 void
finish_do_body(tree do_stmt)763 finish_do_body (tree do_stmt)
764 {
765 tree body = DO_BODY (do_stmt) = pop_stmt_list (DO_BODY (do_stmt));
766
767 if (TREE_CODE (body) == STATEMENT_LIST && STATEMENT_LIST_TAIL (body))
768 body = STATEMENT_LIST_TAIL (body)->stmt;
769
770 if (IS_EMPTY_STMT (body))
771 warning (OPT_Wempty_body,
772 "suggest explicit braces around empty body in %<do%> statement");
773 }
774
775 /* Finish a do-statement, which may be given by DO_STMT, and whose
776 COND is as indicated. */
777
778 void
finish_do_stmt(tree cond,tree do_stmt)779 finish_do_stmt (tree cond, tree do_stmt)
780 {
781 cond = maybe_convert_cond (cond);
782 DO_COND (do_stmt) = cond;
783 finish_stmt ();
784 }
785
786 /* Finish a return-statement. The EXPRESSION returned, if any, is as
787 indicated. */
788
789 tree
finish_return_stmt(tree expr)790 finish_return_stmt (tree expr)
791 {
792 tree r;
793 bool no_warning;
794
795 expr = check_return_expr (expr, &no_warning);
796
797 if (flag_openmp && !check_omp_return ())
798 return error_mark_node;
799 if (!processing_template_decl)
800 {
801 if (warn_sequence_point)
802 verify_sequence_points (expr);
803
804 if (DECL_DESTRUCTOR_P (current_function_decl)
805 || (DECL_CONSTRUCTOR_P (current_function_decl)
806 && targetm.cxx.cdtor_returns_this ()))
807 {
808 /* Similarly, all destructors must run destructors for
809 base-classes before returning. So, all returns in a
810 destructor get sent to the DTOR_LABEL; finish_function emits
811 code to return a value there. */
812 return finish_goto_stmt (cdtor_label);
813 }
814 }
815
816 r = build_stmt (input_location, RETURN_EXPR, expr);
817 TREE_NO_WARNING (r) |= no_warning;
818 r = maybe_cleanup_point_expr_void (r);
819 r = add_stmt (r);
820 finish_stmt ();
821
822 return r;
823 }
824
825 /* Begin the scope of a for-statement or a range-for-statement.
826 Both the returned trees are to be used in a call to
827 begin_for_stmt or begin_range_for_stmt. */
828
829 tree
begin_for_scope(tree * init)830 begin_for_scope (tree *init)
831 {
832 tree scope = NULL_TREE;
833 if (flag_new_for_scope > 0)
834 scope = do_pushlevel (sk_for);
835
836 if (processing_template_decl)
837 *init = push_stmt_list ();
838 else
839 *init = NULL_TREE;
840
841 return scope;
842 }
843
844 /* Begin a for-statement. Returns a new FOR_STMT.
845 SCOPE and INIT should be the return of begin_for_scope,
846 or both NULL_TREE */
847
848 tree
begin_for_stmt(tree scope,tree init)849 begin_for_stmt (tree scope, tree init)
850 {
851 tree r;
852
853 r = build_stmt (input_location, FOR_STMT, NULL_TREE, NULL_TREE,
854 NULL_TREE, NULL_TREE, NULL_TREE);
855
856 if (scope == NULL_TREE)
857 {
858 gcc_assert (!init || !(flag_new_for_scope > 0));
859 if (!init)
860 scope = begin_for_scope (&init);
861 }
862 FOR_INIT_STMT (r) = init;
863 FOR_SCOPE (r) = scope;
864
865 return r;
866 }
867
868 /* Finish the for-init-statement of a for-statement, which may be
869 given by FOR_STMT. */
870
871 void
finish_for_init_stmt(tree for_stmt)872 finish_for_init_stmt (tree for_stmt)
873 {
874 if (processing_template_decl)
875 FOR_INIT_STMT (for_stmt) = pop_stmt_list (FOR_INIT_STMT (for_stmt));
876 add_stmt (for_stmt);
877 FOR_BODY (for_stmt) = do_pushlevel (sk_block);
878 begin_cond (&FOR_COND (for_stmt));
879 }
880
881 /* Finish the COND of a for-statement, which may be given by
882 FOR_STMT. */
883
884 void
finish_for_cond(tree cond,tree for_stmt)885 finish_for_cond (tree cond, tree for_stmt)
886 {
887 finish_cond (&FOR_COND (for_stmt), maybe_convert_cond (cond));
888 simplify_loop_decl_cond (&FOR_COND (for_stmt), FOR_BODY (for_stmt));
889 }
890
891 /* Finish the increment-EXPRESSION in a for-statement, which may be
892 given by FOR_STMT. */
893
894 void
finish_for_expr(tree expr,tree for_stmt)895 finish_for_expr (tree expr, tree for_stmt)
896 {
897 if (!expr)
898 return;
899 /* If EXPR is an overloaded function, issue an error; there is no
900 context available to use to perform overload resolution. */
901 if (type_unknown_p (expr))
902 {
903 cxx_incomplete_type_error (expr, TREE_TYPE (expr));
904 expr = error_mark_node;
905 }
906 if (!processing_template_decl)
907 {
908 if (warn_sequence_point)
909 verify_sequence_points (expr);
910 expr = convert_to_void (expr, ICV_THIRD_IN_FOR,
911 tf_warning_or_error);
912 }
913 else if (!type_dependent_expression_p (expr))
914 convert_to_void (build_non_dependent_expr (expr), ICV_THIRD_IN_FOR,
915 tf_warning_or_error);
916 expr = maybe_cleanup_point_expr_void (expr);
917 if (check_for_bare_parameter_packs (expr))
918 expr = error_mark_node;
919 FOR_EXPR (for_stmt) = expr;
920 }
921
922 /* Finish the body of a for-statement, which may be given by
923 FOR_STMT. The increment-EXPR for the loop must be
924 provided.
925 It can also finish RANGE_FOR_STMT. */
926
927 void
finish_for_stmt(tree for_stmt)928 finish_for_stmt (tree for_stmt)
929 {
930 if (TREE_CODE (for_stmt) == RANGE_FOR_STMT)
931 RANGE_FOR_BODY (for_stmt) = do_poplevel (RANGE_FOR_BODY (for_stmt));
932 else
933 FOR_BODY (for_stmt) = do_poplevel (FOR_BODY (for_stmt));
934
935 /* Pop the scope for the body of the loop. */
936 if (flag_new_for_scope > 0)
937 {
938 tree scope;
939 tree *scope_ptr = (TREE_CODE (for_stmt) == RANGE_FOR_STMT
940 ? &RANGE_FOR_SCOPE (for_stmt)
941 : &FOR_SCOPE (for_stmt));
942 scope = *scope_ptr;
943 *scope_ptr = NULL;
944 add_stmt (do_poplevel (scope));
945 }
946
947 finish_stmt ();
948 }
949
950 /* Begin a range-for-statement. Returns a new RANGE_FOR_STMT.
951 SCOPE and INIT should be the return of begin_for_scope,
952 or both NULL_TREE .
953 To finish it call finish_for_stmt(). */
954
955 tree
begin_range_for_stmt(tree scope,tree init)956 begin_range_for_stmt (tree scope, tree init)
957 {
958 tree r;
959
960 r = build_stmt (input_location, RANGE_FOR_STMT,
961 NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE);
962
963 if (scope == NULL_TREE)
964 {
965 gcc_assert (!init || !(flag_new_for_scope > 0));
966 if (!init)
967 scope = begin_for_scope (&init);
968 }
969
970 /* RANGE_FOR_STMTs do not use nor save the init tree, so we
971 pop it now. */
972 if (init)
973 pop_stmt_list (init);
974 RANGE_FOR_SCOPE (r) = scope;
975
976 return r;
977 }
978
979 /* Finish the head of a range-based for statement, which may
980 be given by RANGE_FOR_STMT. DECL must be the declaration
981 and EXPR must be the loop expression. */
982
983 void
finish_range_for_decl(tree range_for_stmt,tree decl,tree expr)984 finish_range_for_decl (tree range_for_stmt, tree decl, tree expr)
985 {
986 RANGE_FOR_DECL (range_for_stmt) = decl;
987 RANGE_FOR_EXPR (range_for_stmt) = expr;
988 add_stmt (range_for_stmt);
989 RANGE_FOR_BODY (range_for_stmt) = do_pushlevel (sk_block);
990 }
991
992 /* Finish a break-statement. */
993
994 tree
finish_break_stmt(void)995 finish_break_stmt (void)
996 {
997 /* In switch statements break is sometimes stylistically used after
998 a return statement. This can lead to spurious warnings about
999 control reaching the end of a non-void function when it is
1000 inlined. Note that we are calling block_may_fallthru with
1001 language specific tree nodes; this works because
1002 block_may_fallthru returns true when given something it does not
1003 understand. */
1004 if (!block_may_fallthru (cur_stmt_list))
1005 return void_zero_node;
1006 return add_stmt (build_stmt (input_location, BREAK_STMT));
1007 }
1008
1009 /* Finish a continue-statement. */
1010
1011 tree
finish_continue_stmt(void)1012 finish_continue_stmt (void)
1013 {
1014 return add_stmt (build_stmt (input_location, CONTINUE_STMT));
1015 }
1016
1017 /* Begin a switch-statement. Returns a new SWITCH_STMT if
1018 appropriate. */
1019
1020 tree
begin_switch_stmt(void)1021 begin_switch_stmt (void)
1022 {
1023 tree r, scope;
1024
1025 scope = do_pushlevel (sk_cond);
1026 r = build_stmt (input_location, SWITCH_STMT, NULL_TREE, NULL_TREE, NULL_TREE, scope);
1027
1028 begin_cond (&SWITCH_STMT_COND (r));
1029
1030 return r;
1031 }
1032
1033 /* Finish the cond of a switch-statement. */
1034
1035 void
finish_switch_cond(tree cond,tree switch_stmt)1036 finish_switch_cond (tree cond, tree switch_stmt)
1037 {
1038 tree orig_type = NULL;
1039 if (!processing_template_decl)
1040 {
1041 /* Convert the condition to an integer or enumeration type. */
1042 cond = build_expr_type_conversion (WANT_INT | WANT_ENUM, cond, true);
1043 if (cond == NULL_TREE)
1044 {
1045 error ("switch quantity not an integer");
1046 cond = error_mark_node;
1047 }
1048 orig_type = TREE_TYPE (cond);
1049 if (cond != error_mark_node)
1050 {
1051 /* [stmt.switch]
1052
1053 Integral promotions are performed. */
1054 cond = perform_integral_promotions (cond);
1055 cond = maybe_cleanup_point_expr (cond);
1056 }
1057 }
1058 if (check_for_bare_parameter_packs (cond))
1059 cond = error_mark_node;
1060 else if (!processing_template_decl && warn_sequence_point)
1061 verify_sequence_points (cond);
1062
1063 finish_cond (&SWITCH_STMT_COND (switch_stmt), cond);
1064 SWITCH_STMT_TYPE (switch_stmt) = orig_type;
1065 add_stmt (switch_stmt);
1066 push_switch (switch_stmt);
1067 SWITCH_STMT_BODY (switch_stmt) = push_stmt_list ();
1068 }
1069
1070 /* Finish the body of a switch-statement, which may be given by
1071 SWITCH_STMT. The COND to switch on is indicated. */
1072
1073 void
finish_switch_stmt(tree switch_stmt)1074 finish_switch_stmt (tree switch_stmt)
1075 {
1076 tree scope;
1077
1078 SWITCH_STMT_BODY (switch_stmt) =
1079 pop_stmt_list (SWITCH_STMT_BODY (switch_stmt));
1080 pop_switch ();
1081 finish_stmt ();
1082
1083 scope = SWITCH_STMT_SCOPE (switch_stmt);
1084 SWITCH_STMT_SCOPE (switch_stmt) = NULL;
1085 add_stmt (do_poplevel (scope));
1086 }
1087
1088 /* Begin a try-block. Returns a newly-created TRY_BLOCK if
1089 appropriate. */
1090
1091 tree
begin_try_block(void)1092 begin_try_block (void)
1093 {
1094 tree r = build_stmt (input_location, TRY_BLOCK, NULL_TREE, NULL_TREE);
1095 add_stmt (r);
1096 TRY_STMTS (r) = push_stmt_list ();
1097 return r;
1098 }
1099
1100 /* Likewise, for a function-try-block. The block returned in
1101 *COMPOUND_STMT is an artificial outer scope, containing the
1102 function-try-block. */
1103
1104 tree
begin_function_try_block(tree * compound_stmt)1105 begin_function_try_block (tree *compound_stmt)
1106 {
1107 tree r;
1108 /* This outer scope does not exist in the C++ standard, but we need
1109 a place to put __FUNCTION__ and similar variables. */
1110 *compound_stmt = begin_compound_stmt (0);
1111 r = begin_try_block ();
1112 FN_TRY_BLOCK_P (r) = 1;
1113 return r;
1114 }
1115
1116 /* Finish a try-block, which may be given by TRY_BLOCK. */
1117
1118 void
finish_try_block(tree try_block)1119 finish_try_block (tree try_block)
1120 {
1121 TRY_STMTS (try_block) = pop_stmt_list (TRY_STMTS (try_block));
1122 TRY_HANDLERS (try_block) = push_stmt_list ();
1123 }
1124
1125 /* Finish the body of a cleanup try-block, which may be given by
1126 TRY_BLOCK. */
1127
1128 void
finish_cleanup_try_block(tree try_block)1129 finish_cleanup_try_block (tree try_block)
1130 {
1131 TRY_STMTS (try_block) = pop_stmt_list (TRY_STMTS (try_block));
1132 }
1133
1134 /* Finish an implicitly generated try-block, with a cleanup is given
1135 by CLEANUP. */
1136
1137 void
finish_cleanup(tree cleanup,tree try_block)1138 finish_cleanup (tree cleanup, tree try_block)
1139 {
1140 TRY_HANDLERS (try_block) = cleanup;
1141 CLEANUP_P (try_block) = 1;
1142 }
1143
1144 /* Likewise, for a function-try-block. */
1145
1146 void
finish_function_try_block(tree try_block)1147 finish_function_try_block (tree try_block)
1148 {
1149 finish_try_block (try_block);
1150 /* FIXME : something queer about CTOR_INITIALIZER somehow following
1151 the try block, but moving it inside. */
1152 in_function_try_handler = 1;
1153 }
1154
1155 /* Finish a handler-sequence for a try-block, which may be given by
1156 TRY_BLOCK. */
1157
1158 void
finish_handler_sequence(tree try_block)1159 finish_handler_sequence (tree try_block)
1160 {
1161 TRY_HANDLERS (try_block) = pop_stmt_list (TRY_HANDLERS (try_block));
1162 check_handlers (TRY_HANDLERS (try_block));
1163 }
1164
1165 /* Finish the handler-seq for a function-try-block, given by
1166 TRY_BLOCK. COMPOUND_STMT is the outer block created by
1167 begin_function_try_block. */
1168
1169 void
finish_function_handler_sequence(tree try_block,tree compound_stmt)1170 finish_function_handler_sequence (tree try_block, tree compound_stmt)
1171 {
1172 in_function_try_handler = 0;
1173 finish_handler_sequence (try_block);
1174 finish_compound_stmt (compound_stmt);
1175 }
1176
1177 /* Begin a handler. Returns a HANDLER if appropriate. */
1178
1179 tree
begin_handler(void)1180 begin_handler (void)
1181 {
1182 tree r;
1183
1184 r = build_stmt (input_location, HANDLER, NULL_TREE, NULL_TREE);
1185 add_stmt (r);
1186
1187 /* Create a binding level for the eh_info and the exception object
1188 cleanup. */
1189 HANDLER_BODY (r) = do_pushlevel (sk_catch);
1190
1191 return r;
1192 }
1193
1194 /* Finish the handler-parameters for a handler, which may be given by
1195 HANDLER. DECL is the declaration for the catch parameter, or NULL
1196 if this is a `catch (...)' clause. */
1197
1198 void
finish_handler_parms(tree decl,tree handler)1199 finish_handler_parms (tree decl, tree handler)
1200 {
1201 tree type = NULL_TREE;
1202 if (processing_template_decl)
1203 {
1204 if (decl)
1205 {
1206 decl = pushdecl (decl);
1207 decl = push_template_decl (decl);
1208 HANDLER_PARMS (handler) = decl;
1209 type = TREE_TYPE (decl);
1210 }
1211 }
1212 else
1213 type = expand_start_catch_block (decl);
1214 HANDLER_TYPE (handler) = type;
1215 if (!processing_template_decl && type)
1216 mark_used (eh_type_info (type));
1217 }
1218
1219 /* Finish a handler, which may be given by HANDLER. The BLOCKs are
1220 the return value from the matching call to finish_handler_parms. */
1221
1222 void
finish_handler(tree handler)1223 finish_handler (tree handler)
1224 {
1225 if (!processing_template_decl)
1226 expand_end_catch_block ();
1227 HANDLER_BODY (handler) = do_poplevel (HANDLER_BODY (handler));
1228 }
1229
1230 /* Begin a compound statement. FLAGS contains some bits that control the
1231 behavior and context. If BCS_NO_SCOPE is set, the compound statement
1232 does not define a scope. If BCS_FN_BODY is set, this is the outermost
1233 block of a function. If BCS_TRY_BLOCK is set, this is the block
1234 created on behalf of a TRY statement. Returns a token to be passed to
1235 finish_compound_stmt. */
1236
1237 tree
begin_compound_stmt(unsigned int flags)1238 begin_compound_stmt (unsigned int flags)
1239 {
1240 tree r;
1241
1242 if (flags & BCS_NO_SCOPE)
1243 {
1244 r = push_stmt_list ();
1245 STATEMENT_LIST_NO_SCOPE (r) = 1;
1246
1247 /* Normally, we try hard to keep the BLOCK for a statement-expression.
1248 But, if it's a statement-expression with a scopeless block, there's
1249 nothing to keep, and we don't want to accidentally keep a block
1250 *inside* the scopeless block. */
1251 keep_next_level (false);
1252 }
1253 else
1254 r = do_pushlevel (flags & BCS_TRY_BLOCK ? sk_try : sk_block);
1255
1256 /* When processing a template, we need to remember where the braces were,
1257 so that we can set up identical scopes when instantiating the template
1258 later. BIND_EXPR is a handy candidate for this.
1259 Note that do_poplevel won't create a BIND_EXPR itself here (and thus
1260 result in nested BIND_EXPRs), since we don't build BLOCK nodes when
1261 processing templates. */
1262 if (processing_template_decl)
1263 {
1264 r = build3 (BIND_EXPR, NULL, NULL, r, NULL);
1265 BIND_EXPR_TRY_BLOCK (r) = (flags & BCS_TRY_BLOCK) != 0;
1266 BIND_EXPR_BODY_BLOCK (r) = (flags & BCS_FN_BODY) != 0;
1267 TREE_SIDE_EFFECTS (r) = 1;
1268 }
1269
1270 return r;
1271 }
1272
1273 /* Finish a compound-statement, which is given by STMT. */
1274
1275 void
finish_compound_stmt(tree stmt)1276 finish_compound_stmt (tree stmt)
1277 {
1278 if (TREE_CODE (stmt) == BIND_EXPR)
1279 {
1280 tree body = do_poplevel (BIND_EXPR_BODY (stmt));
1281 /* If the STATEMENT_LIST is empty and this BIND_EXPR isn't special,
1282 discard the BIND_EXPR so it can be merged with the containing
1283 STATEMENT_LIST. */
1284 if (TREE_CODE (body) == STATEMENT_LIST
1285 && STATEMENT_LIST_HEAD (body) == NULL
1286 && !BIND_EXPR_BODY_BLOCK (stmt)
1287 && !BIND_EXPR_TRY_BLOCK (stmt))
1288 stmt = body;
1289 else
1290 BIND_EXPR_BODY (stmt) = body;
1291 }
1292 else if (STATEMENT_LIST_NO_SCOPE (stmt))
1293 stmt = pop_stmt_list (stmt);
1294 else
1295 {
1296 /* Destroy any ObjC "super" receivers that may have been
1297 created. */
1298 objc_clear_super_receiver ();
1299
1300 stmt = do_poplevel (stmt);
1301 }
1302
1303 /* ??? See c_end_compound_stmt wrt statement expressions. */
1304 add_stmt (stmt);
1305 finish_stmt ();
1306 }
1307
1308 /* Finish an asm-statement, whose components are a STRING, some
1309 OUTPUT_OPERANDS, some INPUT_OPERANDS, some CLOBBERS and some
1310 LABELS. Also note whether the asm-statement should be
1311 considered volatile. */
1312
1313 tree
finish_asm_stmt(int volatile_p,tree string,tree output_operands,tree input_operands,tree clobbers,tree labels)1314 finish_asm_stmt (int volatile_p, tree string, tree output_operands,
1315 tree input_operands, tree clobbers, tree labels)
1316 {
1317 tree r;
1318 tree t;
1319 int ninputs = list_length (input_operands);
1320 int noutputs = list_length (output_operands);
1321
1322 if (!processing_template_decl)
1323 {
1324 const char *constraint;
1325 const char **oconstraints;
1326 bool allows_mem, allows_reg, is_inout;
1327 tree operand;
1328 int i;
1329
1330 oconstraints = XALLOCAVEC (const char *, noutputs);
1331
1332 string = resolve_asm_operand_names (string, output_operands,
1333 input_operands, labels);
1334
1335 for (i = 0, t = output_operands; t; t = TREE_CHAIN (t), ++i)
1336 {
1337 operand = TREE_VALUE (t);
1338
1339 /* ??? Really, this should not be here. Users should be using a
1340 proper lvalue, dammit. But there's a long history of using
1341 casts in the output operands. In cases like longlong.h, this
1342 becomes a primitive form of typechecking -- if the cast can be
1343 removed, then the output operand had a type of the proper width;
1344 otherwise we'll get an error. Gross, but ... */
1345 STRIP_NOPS (operand);
1346
1347 operand = mark_lvalue_use (operand);
1348
1349 if (!lvalue_or_else (operand, lv_asm, tf_warning_or_error))
1350 operand = error_mark_node;
1351
1352 if (operand != error_mark_node
1353 && (TREE_READONLY (operand)
1354 || CP_TYPE_CONST_P (TREE_TYPE (operand))
1355 /* Functions are not modifiable, even though they are
1356 lvalues. */
1357 || TREE_CODE (TREE_TYPE (operand)) == FUNCTION_TYPE
1358 || TREE_CODE (TREE_TYPE (operand)) == METHOD_TYPE
1359 /* If it's an aggregate and any field is const, then it is
1360 effectively const. */
1361 || (CLASS_TYPE_P (TREE_TYPE (operand))
1362 && C_TYPE_FIELDS_READONLY (TREE_TYPE (operand)))))
1363 cxx_readonly_error (operand, lv_asm);
1364
1365 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t)));
1366 oconstraints[i] = constraint;
1367
1368 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
1369 &allows_mem, &allows_reg, &is_inout))
1370 {
1371 /* If the operand is going to end up in memory,
1372 mark it addressable. */
1373 if (!allows_reg && !cxx_mark_addressable (operand))
1374 operand = error_mark_node;
1375 }
1376 else
1377 operand = error_mark_node;
1378
1379 TREE_VALUE (t) = operand;
1380 }
1381
1382 for (i = 0, t = input_operands; t; ++i, t = TREE_CHAIN (t))
1383 {
1384 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t)));
1385 operand = decay_conversion (TREE_VALUE (t));
1386
1387 /* If the type of the operand hasn't been determined (e.g.,
1388 because it involves an overloaded function), then issue
1389 an error message. There's no context available to
1390 resolve the overloading. */
1391 if (TREE_TYPE (operand) == unknown_type_node)
1392 {
1393 error ("type of asm operand %qE could not be determined",
1394 TREE_VALUE (t));
1395 operand = error_mark_node;
1396 }
1397
1398 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
1399 oconstraints, &allows_mem, &allows_reg))
1400 {
1401 /* If the operand is going to end up in memory,
1402 mark it addressable. */
1403 if (!allows_reg && allows_mem)
1404 {
1405 /* Strip the nops as we allow this case. FIXME, this really
1406 should be rejected or made deprecated. */
1407 STRIP_NOPS (operand);
1408 if (!cxx_mark_addressable (operand))
1409 operand = error_mark_node;
1410 }
1411 }
1412 else
1413 operand = error_mark_node;
1414
1415 TREE_VALUE (t) = operand;
1416 }
1417 }
1418
1419 r = build_stmt (input_location, ASM_EXPR, string,
1420 output_operands, input_operands,
1421 clobbers, labels);
1422 ASM_VOLATILE_P (r) = volatile_p || noutputs == 0;
1423 r = maybe_cleanup_point_expr_void (r);
1424 return add_stmt (r);
1425 }
1426
1427 /* Finish a label with the indicated NAME. Returns the new label. */
1428
1429 tree
finish_label_stmt(tree name)1430 finish_label_stmt (tree name)
1431 {
1432 tree decl = define_label (input_location, name);
1433
1434 if (decl == error_mark_node)
1435 return error_mark_node;
1436
1437 add_stmt (build_stmt (input_location, LABEL_EXPR, decl));
1438
1439 return decl;
1440 }
1441
1442 /* Finish a series of declarations for local labels. G++ allows users
1443 to declare "local" labels, i.e., labels with scope. This extension
1444 is useful when writing code involving statement-expressions. */
1445
1446 void
finish_label_decl(tree name)1447 finish_label_decl (tree name)
1448 {
1449 if (!at_function_scope_p ())
1450 {
1451 error ("__label__ declarations are only allowed in function scopes");
1452 return;
1453 }
1454
1455 add_decl_expr (declare_local_label (name));
1456 }
1457
1458 /* When DECL goes out of scope, make sure that CLEANUP is executed. */
1459
1460 void
finish_decl_cleanup(tree decl,tree cleanup)1461 finish_decl_cleanup (tree decl, tree cleanup)
1462 {
1463 push_cleanup (decl, cleanup, false);
1464 }
1465
1466 /* If the current scope exits with an exception, run CLEANUP. */
1467
1468 void
finish_eh_cleanup(tree cleanup)1469 finish_eh_cleanup (tree cleanup)
1470 {
1471 push_cleanup (NULL, cleanup, true);
1472 }
1473
1474 /* The MEM_INITS is a list of mem-initializers, in reverse of the
1475 order they were written by the user. Each node is as for
1476 emit_mem_initializers. */
1477
1478 void
finish_mem_initializers(tree mem_inits)1479 finish_mem_initializers (tree mem_inits)
1480 {
1481 /* Reorder the MEM_INITS so that they are in the order they appeared
1482 in the source program. */
1483 mem_inits = nreverse (mem_inits);
1484
1485 if (processing_template_decl)
1486 {
1487 tree mem;
1488
1489 for (mem = mem_inits; mem; mem = TREE_CHAIN (mem))
1490 {
1491 /* If the TREE_PURPOSE is a TYPE_PACK_EXPANSION, skip the
1492 check for bare parameter packs in the TREE_VALUE, because
1493 any parameter packs in the TREE_VALUE have already been
1494 bound as part of the TREE_PURPOSE. See
1495 make_pack_expansion for more information. */
1496 if (TREE_CODE (TREE_PURPOSE (mem)) != TYPE_PACK_EXPANSION
1497 && check_for_bare_parameter_packs (TREE_VALUE (mem)))
1498 TREE_VALUE (mem) = error_mark_node;
1499 }
1500
1501 add_stmt (build_min_nt (CTOR_INITIALIZER, mem_inits));
1502 }
1503 else
1504 emit_mem_initializers (mem_inits);
1505 }
1506
1507 /* Finish a parenthesized expression EXPR. */
1508
1509 tree
finish_parenthesized_expr(tree expr)1510 finish_parenthesized_expr (tree expr)
1511 {
1512 if (EXPR_P (expr))
1513 /* This inhibits warnings in c_common_truthvalue_conversion. */
1514 TREE_NO_WARNING (expr) = 1;
1515
1516 if (TREE_CODE (expr) == OFFSET_REF
1517 || TREE_CODE (expr) == SCOPE_REF)
1518 /* [expr.unary.op]/3 The qualified id of a pointer-to-member must not be
1519 enclosed in parentheses. */
1520 PTRMEM_OK_P (expr) = 0;
1521
1522 if (TREE_CODE (expr) == STRING_CST)
1523 PAREN_STRING_LITERAL_P (expr) = 1;
1524
1525 return expr;
1526 }
1527
1528 /* Finish a reference to a non-static data member (DECL) that is not
1529 preceded by `.' or `->'. */
1530
1531 tree
finish_non_static_data_member(tree decl,tree object,tree qualifying_scope)1532 finish_non_static_data_member (tree decl, tree object, tree qualifying_scope)
1533 {
1534 gcc_assert (TREE_CODE (decl) == FIELD_DECL);
1535
1536 if (!object)
1537 {
1538 tree scope = qualifying_scope;
1539 if (scope == NULL_TREE)
1540 scope = context_for_name_lookup (decl);
1541 object = maybe_dummy_object (scope, NULL);
1542 }
1543
1544 if (object == error_mark_node)
1545 return error_mark_node;
1546
1547 /* DR 613: Can use non-static data members without an associated
1548 object in sizeof/decltype/alignof. */
1549 if (is_dummy_object (object) && cp_unevaluated_operand == 0
1550 && (!processing_template_decl || !current_class_ref))
1551 {
1552 if (current_function_decl
1553 && DECL_STATIC_FUNCTION_P (current_function_decl))
1554 error ("invalid use of member %q+D in static member function", decl);
1555 else
1556 error ("invalid use of non-static data member %q+D", decl);
1557 error ("from this location");
1558
1559 return error_mark_node;
1560 }
1561
1562 if (current_class_ptr)
1563 TREE_USED (current_class_ptr) = 1;
1564 if (processing_template_decl && !qualifying_scope)
1565 {
1566 tree type = TREE_TYPE (decl);
1567
1568 if (TREE_CODE (type) == REFERENCE_TYPE)
1569 /* Quals on the object don't matter. */;
1570 else
1571 {
1572 /* Set the cv qualifiers. */
1573 int quals = cp_type_quals (TREE_TYPE (object));
1574
1575 if (DECL_MUTABLE_P (decl))
1576 quals &= ~TYPE_QUAL_CONST;
1577
1578 quals |= cp_type_quals (TREE_TYPE (decl));
1579 type = cp_build_qualified_type (type, quals);
1580 }
1581
1582 return (convert_from_reference
1583 (build_min (COMPONENT_REF, type, object, decl, NULL_TREE)));
1584 }
1585 /* If PROCESSING_TEMPLATE_DECL is nonzero here, then
1586 QUALIFYING_SCOPE is also non-null. Wrap this in a SCOPE_REF
1587 for now. */
1588 else if (processing_template_decl)
1589 return build_qualified_name (TREE_TYPE (decl),
1590 qualifying_scope,
1591 DECL_NAME (decl),
1592 /*template_p=*/false);
1593 else
1594 {
1595 tree access_type = TREE_TYPE (object);
1596
1597 perform_or_defer_access_check (TYPE_BINFO (access_type), decl,
1598 decl);
1599
1600 /* If the data member was named `C::M', convert `*this' to `C'
1601 first. */
1602 if (qualifying_scope)
1603 {
1604 tree binfo = NULL_TREE;
1605 object = build_scoped_ref (object, qualifying_scope,
1606 &binfo);
1607 }
1608
1609 return build_class_member_access_expr (object, decl,
1610 /*access_path=*/NULL_TREE,
1611 /*preserve_reference=*/false,
1612 tf_warning_or_error);
1613 }
1614 }
1615
1616 /* If we are currently parsing a template and we encountered a typedef
1617 TYPEDEF_DECL that is being accessed though CONTEXT, this function
1618 adds the typedef to a list tied to the current template.
1619 At tempate instantiatin time, that list is walked and access check
1620 performed for each typedef.
1621 LOCATION is the location of the usage point of TYPEDEF_DECL. */
1622
1623 void
add_typedef_to_current_template_for_access_check(tree typedef_decl,tree context,location_t location)1624 add_typedef_to_current_template_for_access_check (tree typedef_decl,
1625 tree context,
1626 location_t location)
1627 {
1628 tree template_info = NULL;
1629 tree cs = current_scope ();
1630
1631 if (!is_typedef_decl (typedef_decl)
1632 || !context
1633 || !CLASS_TYPE_P (context)
1634 || !cs)
1635 return;
1636
1637 if (CLASS_TYPE_P (cs) || TREE_CODE (cs) == FUNCTION_DECL)
1638 template_info = get_template_info (cs);
1639
1640 if (template_info
1641 && TI_TEMPLATE (template_info)
1642 && !currently_open_class (context))
1643 append_type_to_template_for_access_check (cs, typedef_decl,
1644 context, location);
1645 }
1646
1647 /* DECL was the declaration to which a qualified-id resolved. Issue
1648 an error message if it is not accessible. If OBJECT_TYPE is
1649 non-NULL, we have just seen `x->' or `x.' and OBJECT_TYPE is the
1650 type of `*x', or `x', respectively. If the DECL was named as
1651 `A::B' then NESTED_NAME_SPECIFIER is `A'. */
1652
1653 void
check_accessibility_of_qualified_id(tree decl,tree object_type,tree nested_name_specifier)1654 check_accessibility_of_qualified_id (tree decl,
1655 tree object_type,
1656 tree nested_name_specifier)
1657 {
1658 tree scope;
1659 tree qualifying_type = NULL_TREE;
1660
1661 /* If we are parsing a template declaration and if decl is a typedef,
1662 add it to a list tied to the template.
1663 At template instantiation time, that list will be walked and
1664 access check performed. */
1665 add_typedef_to_current_template_for_access_check (decl,
1666 nested_name_specifier
1667 ? nested_name_specifier
1668 : DECL_CONTEXT (decl),
1669 input_location);
1670
1671 /* If we're not checking, return immediately. */
1672 if (deferred_access_no_check)
1673 return;
1674
1675 /* Determine the SCOPE of DECL. */
1676 scope = context_for_name_lookup (decl);
1677 /* If the SCOPE is not a type, then DECL is not a member. */
1678 if (!TYPE_P (scope))
1679 return;
1680 /* Compute the scope through which DECL is being accessed. */
1681 if (object_type
1682 /* OBJECT_TYPE might not be a class type; consider:
1683
1684 class A { typedef int I; };
1685 I *p;
1686 p->A::I::~I();
1687
1688 In this case, we will have "A::I" as the DECL, but "I" as the
1689 OBJECT_TYPE. */
1690 && CLASS_TYPE_P (object_type)
1691 && DERIVED_FROM_P (scope, object_type))
1692 /* If we are processing a `->' or `.' expression, use the type of the
1693 left-hand side. */
1694 qualifying_type = object_type;
1695 else if (nested_name_specifier)
1696 {
1697 /* If the reference is to a non-static member of the
1698 current class, treat it as if it were referenced through
1699 `this'. */
1700 if (DECL_NONSTATIC_MEMBER_P (decl)
1701 && current_class_ptr
1702 && DERIVED_FROM_P (scope, current_class_type))
1703 qualifying_type = current_class_type;
1704 /* Otherwise, use the type indicated by the
1705 nested-name-specifier. */
1706 else
1707 qualifying_type = nested_name_specifier;
1708 }
1709 else
1710 /* Otherwise, the name must be from the current class or one of
1711 its bases. */
1712 qualifying_type = currently_open_derived_class (scope);
1713
1714 if (qualifying_type
1715 /* It is possible for qualifying type to be a TEMPLATE_TYPE_PARM
1716 or similar in a default argument value. */
1717 && CLASS_TYPE_P (qualifying_type)
1718 && !dependent_type_p (qualifying_type))
1719 perform_or_defer_access_check (TYPE_BINFO (qualifying_type), decl,
1720 decl);
1721 }
1722
1723 /* EXPR is the result of a qualified-id. The QUALIFYING_CLASS was the
1724 class named to the left of the "::" operator. DONE is true if this
1725 expression is a complete postfix-expression; it is false if this
1726 expression is followed by '->', '[', '(', etc. ADDRESS_P is true
1727 iff this expression is the operand of '&'. TEMPLATE_P is true iff
1728 the qualified-id was of the form "A::template B". TEMPLATE_ARG_P
1729 is true iff this qualified name appears as a template argument. */
1730
1731 tree
finish_qualified_id_expr(tree qualifying_class,tree expr,bool done,bool address_p,bool template_p,bool template_arg_p)1732 finish_qualified_id_expr (tree qualifying_class,
1733 tree expr,
1734 bool done,
1735 bool address_p,
1736 bool template_p,
1737 bool template_arg_p)
1738 {
1739 gcc_assert (TYPE_P (qualifying_class));
1740
1741 if (error_operand_p (expr))
1742 return error_mark_node;
1743
1744 if (DECL_P (expr) || BASELINK_P (expr))
1745 mark_used (expr);
1746
1747 if (template_p)
1748 check_template_keyword (expr);
1749
1750 /* If EXPR occurs as the operand of '&', use special handling that
1751 permits a pointer-to-member. */
1752 if (address_p && done)
1753 {
1754 if (TREE_CODE (expr) == SCOPE_REF)
1755 expr = TREE_OPERAND (expr, 1);
1756 expr = build_offset_ref (qualifying_class, expr,
1757 /*address_p=*/true);
1758 return expr;
1759 }
1760
1761 /* Within the scope of a class, turn references to non-static
1762 members into expression of the form "this->...". */
1763 if (template_arg_p)
1764 /* But, within a template argument, we do not want make the
1765 transformation, as there is no "this" pointer. */
1766 ;
1767 else if (TREE_CODE (expr) == FIELD_DECL)
1768 {
1769 push_deferring_access_checks (dk_no_check);
1770 expr = finish_non_static_data_member (expr, NULL_TREE,
1771 qualifying_class);
1772 pop_deferring_access_checks ();
1773 }
1774 else if (BASELINK_P (expr) && !processing_template_decl)
1775 {
1776 tree ob;
1777
1778 /* See if any of the functions are non-static members. */
1779 /* If so, the expression may be relative to 'this'. */
1780 if (!shared_member_p (expr)
1781 && (ob = maybe_dummy_object (qualifying_class, NULL),
1782 !is_dummy_object (ob)))
1783 expr = (build_class_member_access_expr
1784 (ob,
1785 expr,
1786 BASELINK_ACCESS_BINFO (expr),
1787 /*preserve_reference=*/false,
1788 tf_warning_or_error));
1789 else if (done)
1790 /* The expression is a qualified name whose address is not
1791 being taken. */
1792 expr = build_offset_ref (qualifying_class, expr, /*address_p=*/false);
1793 }
1794
1795 return expr;
1796 }
1797
1798 /* Begin a statement-expression. The value returned must be passed to
1799 finish_stmt_expr. */
1800
1801 tree
begin_stmt_expr(void)1802 begin_stmt_expr (void)
1803 {
1804 return push_stmt_list ();
1805 }
1806
1807 /* Process the final expression of a statement expression. EXPR can be
1808 NULL, if the final expression is empty. Return a STATEMENT_LIST
1809 containing all the statements in the statement-expression, or
1810 ERROR_MARK_NODE if there was an error. */
1811
1812 tree
finish_stmt_expr_expr(tree expr,tree stmt_expr)1813 finish_stmt_expr_expr (tree expr, tree stmt_expr)
1814 {
1815 if (error_operand_p (expr))
1816 {
1817 /* The type of the statement-expression is the type of the last
1818 expression. */
1819 TREE_TYPE (stmt_expr) = error_mark_node;
1820 return error_mark_node;
1821 }
1822
1823 /* If the last statement does not have "void" type, then the value
1824 of the last statement is the value of the entire expression. */
1825 if (expr)
1826 {
1827 tree type = TREE_TYPE (expr);
1828
1829 if (processing_template_decl)
1830 {
1831 expr = build_stmt (input_location, EXPR_STMT, expr);
1832 expr = add_stmt (expr);
1833 /* Mark the last statement so that we can recognize it as such at
1834 template-instantiation time. */
1835 EXPR_STMT_STMT_EXPR_RESULT (expr) = 1;
1836 }
1837 else if (VOID_TYPE_P (type))
1838 {
1839 /* Just treat this like an ordinary statement. */
1840 expr = finish_expr_stmt (expr);
1841 }
1842 else
1843 {
1844 /* It actually has a value we need to deal with. First, force it
1845 to be an rvalue so that we won't need to build up a copy
1846 constructor call later when we try to assign it to something. */
1847 expr = force_rvalue (expr, tf_warning_or_error);
1848 if (error_operand_p (expr))
1849 return error_mark_node;
1850
1851 /* Update for array-to-pointer decay. */
1852 type = TREE_TYPE (expr);
1853
1854 /* Wrap it in a CLEANUP_POINT_EXPR and add it to the list like a
1855 normal statement, but don't convert to void or actually add
1856 the EXPR_STMT. */
1857 if (TREE_CODE (expr) != CLEANUP_POINT_EXPR)
1858 expr = maybe_cleanup_point_expr (expr);
1859 add_stmt (expr);
1860 }
1861
1862 /* The type of the statement-expression is the type of the last
1863 expression. */
1864 TREE_TYPE (stmt_expr) = type;
1865 }
1866
1867 return stmt_expr;
1868 }
1869
1870 /* Finish a statement-expression. EXPR should be the value returned
1871 by the previous begin_stmt_expr. Returns an expression
1872 representing the statement-expression. */
1873
1874 tree
finish_stmt_expr(tree stmt_expr,bool has_no_scope)1875 finish_stmt_expr (tree stmt_expr, bool has_no_scope)
1876 {
1877 tree type;
1878 tree result;
1879
1880 if (error_operand_p (stmt_expr))
1881 {
1882 pop_stmt_list (stmt_expr);
1883 return error_mark_node;
1884 }
1885
1886 gcc_assert (TREE_CODE (stmt_expr) == STATEMENT_LIST);
1887
1888 type = TREE_TYPE (stmt_expr);
1889 result = pop_stmt_list (stmt_expr);
1890 TREE_TYPE (result) = type;
1891
1892 if (processing_template_decl)
1893 {
1894 result = build_min (STMT_EXPR, type, result);
1895 TREE_SIDE_EFFECTS (result) = 1;
1896 STMT_EXPR_NO_SCOPE (result) = has_no_scope;
1897 }
1898 else if (CLASS_TYPE_P (type))
1899 {
1900 /* Wrap the statement-expression in a TARGET_EXPR so that the
1901 temporary object created by the final expression is destroyed at
1902 the end of the full-expression containing the
1903 statement-expression. */
1904 result = force_target_expr (type, result, tf_warning_or_error);
1905 }
1906
1907 return result;
1908 }
1909
1910 /* Returns the expression which provides the value of STMT_EXPR. */
1911
1912 tree
stmt_expr_value_expr(tree stmt_expr)1913 stmt_expr_value_expr (tree stmt_expr)
1914 {
1915 tree t = STMT_EXPR_STMT (stmt_expr);
1916
1917 if (TREE_CODE (t) == BIND_EXPR)
1918 t = BIND_EXPR_BODY (t);
1919
1920 if (TREE_CODE (t) == STATEMENT_LIST && STATEMENT_LIST_TAIL (t))
1921 t = STATEMENT_LIST_TAIL (t)->stmt;
1922
1923 if (TREE_CODE (t) == EXPR_STMT)
1924 t = EXPR_STMT_EXPR (t);
1925
1926 return t;
1927 }
1928
1929 /* Return TRUE iff EXPR_STMT is an empty list of
1930 expression statements. */
1931
1932 bool
empty_expr_stmt_p(tree expr_stmt)1933 empty_expr_stmt_p (tree expr_stmt)
1934 {
1935 tree body = NULL_TREE;
1936
1937 if (expr_stmt == void_zero_node)
1938 return true;
1939
1940 if (expr_stmt)
1941 {
1942 if (TREE_CODE (expr_stmt) == EXPR_STMT)
1943 body = EXPR_STMT_EXPR (expr_stmt);
1944 else if (TREE_CODE (expr_stmt) == STATEMENT_LIST)
1945 body = expr_stmt;
1946 }
1947
1948 if (body)
1949 {
1950 if (TREE_CODE (body) == STATEMENT_LIST)
1951 return tsi_end_p (tsi_start (body));
1952 else
1953 return empty_expr_stmt_p (body);
1954 }
1955 return false;
1956 }
1957
1958 /* Perform Koenig lookup. FN is the postfix-expression representing
1959 the function (or functions) to call; ARGS are the arguments to the
1960 call; if INCLUDE_STD then the `std' namespace is automatically
1961 considered an associated namespace (used in range-based for loops).
1962 Returns the functions to be considered by overload resolution. */
1963
1964 tree
perform_koenig_lookup(tree fn,VEC (tree,gc)* args,bool include_std,tsubst_flags_t complain)1965 perform_koenig_lookup (tree fn, VEC(tree,gc) *args, bool include_std,
1966 tsubst_flags_t complain)
1967 {
1968 tree identifier = NULL_TREE;
1969 tree functions = NULL_TREE;
1970 tree tmpl_args = NULL_TREE;
1971 bool template_id = false;
1972
1973 if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
1974 {
1975 /* Use a separate flag to handle null args. */
1976 template_id = true;
1977 tmpl_args = TREE_OPERAND (fn, 1);
1978 fn = TREE_OPERAND (fn, 0);
1979 }
1980
1981 /* Find the name of the overloaded function. */
1982 if (TREE_CODE (fn) == IDENTIFIER_NODE)
1983 identifier = fn;
1984 else if (is_overloaded_fn (fn))
1985 {
1986 functions = fn;
1987 identifier = DECL_NAME (get_first_fn (functions));
1988 }
1989 else if (DECL_P (fn))
1990 {
1991 functions = fn;
1992 identifier = DECL_NAME (fn);
1993 }
1994
1995 /* A call to a namespace-scope function using an unqualified name.
1996
1997 Do Koenig lookup -- unless any of the arguments are
1998 type-dependent. */
1999 if (!any_type_dependent_arguments_p (args)
2000 && !any_dependent_template_arguments_p (tmpl_args))
2001 {
2002 fn = lookup_arg_dependent (identifier, functions, args, include_std);
2003 if (!fn)
2004 {
2005 /* The unqualified name could not be resolved. */
2006 if (complain)
2007 fn = unqualified_fn_lookup_error (identifier);
2008 else
2009 fn = identifier;
2010 }
2011 }
2012
2013 if (fn && template_id)
2014 fn = build2 (TEMPLATE_ID_EXPR, unknown_type_node, fn, tmpl_args);
2015
2016 return fn;
2017 }
2018
2019 /* Generate an expression for `FN (ARGS)'. This may change the
2020 contents of ARGS.
2021
2022 If DISALLOW_VIRTUAL is true, the call to FN will be not generated
2023 as a virtual call, even if FN is virtual. (This flag is set when
2024 encountering an expression where the function name is explicitly
2025 qualified. For example a call to `X::f' never generates a virtual
2026 call.)
2027
2028 Returns code for the call. */
2029
2030 tree
finish_call_expr(tree fn,VEC (tree,gc)** args,bool disallow_virtual,bool koenig_p,tsubst_flags_t complain)2031 finish_call_expr (tree fn, VEC(tree,gc) **args, bool disallow_virtual,
2032 bool koenig_p, tsubst_flags_t complain)
2033 {
2034 tree result;
2035 tree orig_fn;
2036 VEC(tree,gc) *orig_args = NULL;
2037
2038 if (fn == error_mark_node)
2039 return error_mark_node;
2040
2041 gcc_assert (!TYPE_P (fn));
2042
2043 orig_fn = fn;
2044
2045 if (processing_template_decl)
2046 {
2047 /* If the call expression is dependent, build a CALL_EXPR node
2048 with no type; type_dependent_expression_p recognizes
2049 expressions with no type as being dependent. */
2050 if (type_dependent_expression_p (fn)
2051 || any_type_dependent_arguments_p (*args)
2052 /* For a non-static member function that doesn't have an
2053 explicit object argument, we need to specifically
2054 test the type dependency of the "this" pointer because it
2055 is not included in *ARGS even though it is considered to
2056 be part of the list of arguments. Note that this is
2057 related to CWG issues 515 and 1005. */
2058 || (TREE_CODE (fn) != COMPONENT_REF
2059 && non_static_member_function_p (fn)
2060 && current_class_ref
2061 && type_dependent_expression_p (current_class_ref)))
2062 {
2063 result = build_nt_call_vec (fn, *args);
2064 KOENIG_LOOKUP_P (result) = koenig_p;
2065 if (cfun)
2066 {
2067 do
2068 {
2069 tree fndecl = OVL_CURRENT (fn);
2070 if (TREE_CODE (fndecl) != FUNCTION_DECL
2071 || !TREE_THIS_VOLATILE (fndecl))
2072 break;
2073 fn = OVL_NEXT (fn);
2074 }
2075 while (fn);
2076 if (!fn)
2077 current_function_returns_abnormally = 1;
2078 }
2079 return result;
2080 }
2081 orig_args = make_tree_vector_copy (*args);
2082 if (!BASELINK_P (fn)
2083 && TREE_CODE (fn) != PSEUDO_DTOR_EXPR
2084 && TREE_TYPE (fn) != unknown_type_node)
2085 fn = build_non_dependent_expr (fn);
2086 make_args_non_dependent (*args);
2087 }
2088
2089 if (TREE_CODE (fn) == COMPONENT_REF)
2090 {
2091 tree member = TREE_OPERAND (fn, 1);
2092 if (BASELINK_P (member))
2093 {
2094 tree object = TREE_OPERAND (fn, 0);
2095 return build_new_method_call (object, member,
2096 args, NULL_TREE,
2097 (disallow_virtual
2098 ? LOOKUP_NORMAL | LOOKUP_NONVIRTUAL
2099 : LOOKUP_NORMAL),
2100 /*fn_p=*/NULL,
2101 complain);
2102 }
2103 }
2104
2105 if (is_overloaded_fn (fn))
2106 fn = baselink_for_fns (fn);
2107
2108 result = NULL_TREE;
2109 if (BASELINK_P (fn))
2110 {
2111 tree object;
2112
2113 /* A call to a member function. From [over.call.func]:
2114
2115 If the keyword this is in scope and refers to the class of
2116 that member function, or a derived class thereof, then the
2117 function call is transformed into a qualified function call
2118 using (*this) as the postfix-expression to the left of the
2119 . operator.... [Otherwise] a contrived object of type T
2120 becomes the implied object argument.
2121
2122 In this situation:
2123
2124 struct A { void f(); };
2125 struct B : public A {};
2126 struct C : public A { void g() { B::f(); }};
2127
2128 "the class of that member function" refers to `A'. But 11.2
2129 [class.access.base] says that we need to convert 'this' to B* as
2130 part of the access, so we pass 'B' to maybe_dummy_object. */
2131
2132 object = maybe_dummy_object (BINFO_TYPE (BASELINK_ACCESS_BINFO (fn)),
2133 NULL);
2134
2135 if (processing_template_decl)
2136 {
2137 if (type_dependent_expression_p (object))
2138 {
2139 tree ret = build_nt_call_vec (orig_fn, orig_args);
2140 release_tree_vector (orig_args);
2141 return ret;
2142 }
2143 object = build_non_dependent_expr (object);
2144 }
2145
2146 result = build_new_method_call (object, fn, args, NULL_TREE,
2147 (disallow_virtual
2148 ? LOOKUP_NORMAL|LOOKUP_NONVIRTUAL
2149 : LOOKUP_NORMAL),
2150 /*fn_p=*/NULL,
2151 complain);
2152 }
2153 else if (is_overloaded_fn (fn))
2154 {
2155 /* If the function is an overloaded builtin, resolve it. */
2156 if (TREE_CODE (fn) == FUNCTION_DECL
2157 && (DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL
2158 || DECL_BUILT_IN_CLASS (fn) == BUILT_IN_MD))
2159 result = resolve_overloaded_builtin (input_location, fn, *args);
2160
2161 if (!result)
2162 /* A call to a namespace-scope function. */
2163 result = build_new_function_call (fn, args, koenig_p, complain);
2164 }
2165 else if (TREE_CODE (fn) == PSEUDO_DTOR_EXPR)
2166 {
2167 if (!VEC_empty (tree, *args))
2168 error ("arguments to destructor are not allowed");
2169 /* Mark the pseudo-destructor call as having side-effects so
2170 that we do not issue warnings about its use. */
2171 result = build1 (NOP_EXPR,
2172 void_type_node,
2173 TREE_OPERAND (fn, 0));
2174 TREE_SIDE_EFFECTS (result) = 1;
2175 }
2176 else if (CLASS_TYPE_P (TREE_TYPE (fn)))
2177 /* If the "function" is really an object of class type, it might
2178 have an overloaded `operator ()'. */
2179 result = build_op_call (fn, args, complain);
2180
2181 if (!result)
2182 /* A call where the function is unknown. */
2183 result = cp_build_function_call_vec (fn, args, complain);
2184
2185 if (processing_template_decl && result != error_mark_node)
2186 {
2187 if (TREE_CODE (result) == INDIRECT_REF)
2188 result = TREE_OPERAND (result, 0);
2189 result = build_call_vec (TREE_TYPE (result), orig_fn, orig_args);
2190 SET_EXPR_LOCATION (result, input_location);
2191 KOENIG_LOOKUP_P (result) = koenig_p;
2192 release_tree_vector (orig_args);
2193 result = convert_from_reference (result);
2194 }
2195
2196 if (koenig_p)
2197 {
2198 /* Free garbage OVERLOADs from arg-dependent lookup. */
2199 tree next = NULL_TREE;
2200 for (fn = orig_fn;
2201 fn && TREE_CODE (fn) == OVERLOAD && OVL_ARG_DEPENDENT (fn);
2202 fn = next)
2203 {
2204 if (processing_template_decl)
2205 /* In a template, we'll re-use them at instantiation time. */
2206 OVL_ARG_DEPENDENT (fn) = false;
2207 else
2208 {
2209 next = OVL_CHAIN (fn);
2210 ggc_free (fn);
2211 }
2212 }
2213 }
2214
2215 return result;
2216 }
2217
2218 /* Finish a call to a postfix increment or decrement or EXPR. (Which
2219 is indicated by CODE, which should be POSTINCREMENT_EXPR or
2220 POSTDECREMENT_EXPR.) */
2221
2222 tree
finish_increment_expr(tree expr,enum tree_code code)2223 finish_increment_expr (tree expr, enum tree_code code)
2224 {
2225 return build_x_unary_op (code, expr, tf_warning_or_error);
2226 }
2227
2228 /* Finish a use of `this'. Returns an expression for `this'. */
2229
2230 tree
finish_this_expr(void)2231 finish_this_expr (void)
2232 {
2233 tree result;
2234
2235 if (current_class_ptr)
2236 {
2237 tree type = TREE_TYPE (current_class_ref);
2238
2239 /* In a lambda expression, 'this' refers to the captured 'this'. */
2240 if (LAMBDA_TYPE_P (type))
2241 result = lambda_expr_this_capture (CLASSTYPE_LAMBDA_EXPR (type));
2242 else
2243 result = current_class_ptr;
2244
2245 }
2246 else if (current_function_decl
2247 && DECL_STATIC_FUNCTION_P (current_function_decl))
2248 {
2249 error ("%<this%> is unavailable for static member functions");
2250 result = error_mark_node;
2251 }
2252 else
2253 {
2254 if (current_function_decl)
2255 error ("invalid use of %<this%> in non-member function");
2256 else
2257 error ("invalid use of %<this%> at top level");
2258 result = error_mark_node;
2259 }
2260
2261 return result;
2262 }
2263
2264 /* Finish a pseudo-destructor expression. If SCOPE is NULL, the
2265 expression was of the form `OBJECT.~DESTRUCTOR' where DESTRUCTOR is
2266 the TYPE for the type given. If SCOPE is non-NULL, the expression
2267 was of the form `OBJECT.SCOPE::~DESTRUCTOR'. */
2268
2269 tree
finish_pseudo_destructor_expr(tree object,tree scope,tree destructor)2270 finish_pseudo_destructor_expr (tree object, tree scope, tree destructor)
2271 {
2272 if (object == error_mark_node || destructor == error_mark_node)
2273 return error_mark_node;
2274
2275 gcc_assert (TYPE_P (destructor));
2276
2277 if (!processing_template_decl)
2278 {
2279 if (scope == error_mark_node)
2280 {
2281 error ("invalid qualifying scope in pseudo-destructor name");
2282 return error_mark_node;
2283 }
2284 if (scope && TYPE_P (scope) && !check_dtor_name (scope, destructor))
2285 {
2286 error ("qualified type %qT does not match destructor name ~%qT",
2287 scope, destructor);
2288 return error_mark_node;
2289 }
2290
2291
2292 /* [expr.pseudo] says both:
2293
2294 The type designated by the pseudo-destructor-name shall be
2295 the same as the object type.
2296
2297 and:
2298
2299 The cv-unqualified versions of the object type and of the
2300 type designated by the pseudo-destructor-name shall be the
2301 same type.
2302
2303 We implement the more generous second sentence, since that is
2304 what most other compilers do. */
2305 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (object),
2306 destructor))
2307 {
2308 error ("%qE is not of type %qT", object, destructor);
2309 return error_mark_node;
2310 }
2311 }
2312
2313 return build3 (PSEUDO_DTOR_EXPR, void_type_node, object, scope, destructor);
2314 }
2315
2316 /* Finish an expression of the form CODE EXPR. */
2317
2318 tree
finish_unary_op_expr(enum tree_code code,tree expr)2319 finish_unary_op_expr (enum tree_code code, tree expr)
2320 {
2321 tree result = build_x_unary_op (code, expr, tf_warning_or_error);
2322 if (TREE_OVERFLOW_P (result) && !TREE_OVERFLOW_P (expr))
2323 overflow_warning (input_location, result);
2324
2325 return result;
2326 }
2327
2328 /* Finish a compound-literal expression. TYPE is the type to which
2329 the CONSTRUCTOR in COMPOUND_LITERAL is being cast. */
2330
2331 tree
finish_compound_literal(tree type,tree compound_literal,tsubst_flags_t complain)2332 finish_compound_literal (tree type, tree compound_literal,
2333 tsubst_flags_t complain)
2334 {
2335 if (type == error_mark_node)
2336 return error_mark_node;
2337
2338 if (TREE_CODE (type) == REFERENCE_TYPE)
2339 {
2340 compound_literal
2341 = finish_compound_literal (TREE_TYPE (type), compound_literal,
2342 complain);
2343 return cp_build_c_cast (type, compound_literal, complain);
2344 }
2345
2346 if (!TYPE_OBJ_P (type))
2347 {
2348 if (complain & tf_error)
2349 error ("compound literal of non-object type %qT", type);
2350 return error_mark_node;
2351 }
2352
2353 if (processing_template_decl)
2354 {
2355 TREE_TYPE (compound_literal) = type;
2356 /* Mark the expression as a compound literal. */
2357 TREE_HAS_CONSTRUCTOR (compound_literal) = 1;
2358 return compound_literal;
2359 }
2360
2361 type = complete_type (type);
2362
2363 if (TYPE_NON_AGGREGATE_CLASS (type))
2364 {
2365 /* Trying to deal with a CONSTRUCTOR instead of a TREE_LIST
2366 everywhere that deals with function arguments would be a pain, so
2367 just wrap it in a TREE_LIST. The parser set a flag so we know
2368 that it came from T{} rather than T({}). */
2369 CONSTRUCTOR_IS_DIRECT_INIT (compound_literal) = 1;
2370 compound_literal = build_tree_list (NULL_TREE, compound_literal);
2371 return build_functional_cast (type, compound_literal, complain);
2372 }
2373
2374 if (TREE_CODE (type) == ARRAY_TYPE
2375 && check_array_initializer (NULL_TREE, type, compound_literal))
2376 return error_mark_node;
2377 compound_literal = reshape_init (type, compound_literal, complain);
2378 if (SCALAR_TYPE_P (type)
2379 && !BRACE_ENCLOSED_INITIALIZER_P (compound_literal)
2380 && (complain & tf_warning_or_error))
2381 check_narrowing (type, compound_literal);
2382 if (TREE_CODE (type) == ARRAY_TYPE
2383 && TYPE_DOMAIN (type) == NULL_TREE)
2384 {
2385 cp_complete_array_type_or_error (&type, compound_literal,
2386 false, complain);
2387 if (type == error_mark_node)
2388 return error_mark_node;
2389 }
2390 compound_literal = digest_init (type, compound_literal, complain);
2391 if (TREE_CODE (compound_literal) == CONSTRUCTOR)
2392 TREE_HAS_CONSTRUCTOR (compound_literal) = true;
2393 /* Put static/constant array temporaries in static variables, but always
2394 represent class temporaries with TARGET_EXPR so we elide copies. */
2395 if ((!at_function_scope_p () || CP_TYPE_CONST_P (type))
2396 && TREE_CODE (type) == ARRAY_TYPE
2397 && !TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
2398 && initializer_constant_valid_p (compound_literal, type))
2399 {
2400 tree decl = create_temporary_var (type);
2401 DECL_INITIAL (decl) = compound_literal;
2402 TREE_STATIC (decl) = 1;
2403 if (literal_type_p (type) && CP_TYPE_CONST_NON_VOLATILE_P (type))
2404 {
2405 /* 5.19 says that a constant expression can include an
2406 lvalue-rvalue conversion applied to "a glvalue of literal type
2407 that refers to a non-volatile temporary object initialized
2408 with a constant expression". Rather than try to communicate
2409 that this VAR_DECL is a temporary, just mark it constexpr. */
2410 DECL_DECLARED_CONSTEXPR_P (decl) = true;
2411 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = true;
2412 TREE_CONSTANT (decl) = true;
2413 }
2414 cp_apply_type_quals_to_decl (cp_type_quals (type), decl);
2415 decl = pushdecl_top_level (decl);
2416 DECL_NAME (decl) = make_anon_name ();
2417 SET_DECL_ASSEMBLER_NAME (decl, DECL_NAME (decl));
2418 return decl;
2419 }
2420 else
2421 return get_target_expr_sfinae (compound_literal, complain);
2422 }
2423
2424 /* Return the declaration for the function-name variable indicated by
2425 ID. */
2426
2427 tree
finish_fname(tree id)2428 finish_fname (tree id)
2429 {
2430 tree decl;
2431
2432 decl = fname_decl (input_location, C_RID_CODE (id), id);
2433 if (processing_template_decl && current_function_decl
2434 && decl != error_mark_node)
2435 decl = DECL_NAME (decl);
2436 return decl;
2437 }
2438
2439 /* Finish a translation unit. */
2440
2441 void
finish_translation_unit(void)2442 finish_translation_unit (void)
2443 {
2444 /* In case there were missing closebraces,
2445 get us back to the global binding level. */
2446 pop_everything ();
2447 while (current_namespace != global_namespace)
2448 pop_namespace ();
2449
2450 /* Do file scope __FUNCTION__ et al. */
2451 finish_fname_decls ();
2452 }
2453
2454 /* Finish a template type parameter, specified as AGGR IDENTIFIER.
2455 Returns the parameter. */
2456
2457 tree
finish_template_type_parm(tree aggr,tree identifier)2458 finish_template_type_parm (tree aggr, tree identifier)
2459 {
2460 if (aggr != class_type_node)
2461 {
2462 permerror (input_location, "template type parameters must use the keyword %<class%> or %<typename%>");
2463 aggr = class_type_node;
2464 }
2465
2466 return build_tree_list (aggr, identifier);
2467 }
2468
2469 /* Finish a template template parameter, specified as AGGR IDENTIFIER.
2470 Returns the parameter. */
2471
2472 tree
finish_template_template_parm(tree aggr,tree identifier)2473 finish_template_template_parm (tree aggr, tree identifier)
2474 {
2475 tree decl = build_decl (input_location,
2476 TYPE_DECL, identifier, NULL_TREE);
2477 tree tmpl = build_lang_decl (TEMPLATE_DECL, identifier, NULL_TREE);
2478 DECL_TEMPLATE_PARMS (tmpl) = current_template_parms;
2479 DECL_TEMPLATE_RESULT (tmpl) = decl;
2480 DECL_ARTIFICIAL (decl) = 1;
2481 end_template_decl ();
2482
2483 gcc_assert (DECL_TEMPLATE_PARMS (tmpl));
2484
2485 check_default_tmpl_args (decl, DECL_TEMPLATE_PARMS (tmpl),
2486 /*is_primary=*/true, /*is_partial=*/false,
2487 /*is_friend=*/0);
2488
2489 return finish_template_type_parm (aggr, tmpl);
2490 }
2491
2492 /* ARGUMENT is the default-argument value for a template template
2493 parameter. If ARGUMENT is invalid, issue error messages and return
2494 the ERROR_MARK_NODE. Otherwise, ARGUMENT itself is returned. */
2495
2496 tree
check_template_template_default_arg(tree argument)2497 check_template_template_default_arg (tree argument)
2498 {
2499 if (TREE_CODE (argument) != TEMPLATE_DECL
2500 && TREE_CODE (argument) != TEMPLATE_TEMPLATE_PARM
2501 && TREE_CODE (argument) != UNBOUND_CLASS_TEMPLATE)
2502 {
2503 if (TREE_CODE (argument) == TYPE_DECL)
2504 error ("invalid use of type %qT as a default value for a template "
2505 "template-parameter", TREE_TYPE (argument));
2506 else
2507 error ("invalid default argument for a template template parameter");
2508 return error_mark_node;
2509 }
2510
2511 return argument;
2512 }
2513
2514 /* Begin a class definition, as indicated by T. */
2515
2516 tree
begin_class_definition(tree t)2517 begin_class_definition (tree t)
2518 {
2519 if (error_operand_p (t) || error_operand_p (TYPE_MAIN_DECL (t)))
2520 return error_mark_node;
2521
2522 if (processing_template_parmlist)
2523 {
2524 error ("definition of %q#T inside template parameter list", t);
2525 return error_mark_node;
2526 }
2527
2528 /* According to the C++ ABI, decimal classes defined in ISO/IEC TR 24733
2529 are passed the same as decimal scalar types. */
2530 if (TREE_CODE (t) == RECORD_TYPE
2531 && !processing_template_decl)
2532 {
2533 tree ns = TYPE_CONTEXT (t);
2534 if (ns && TREE_CODE (ns) == NAMESPACE_DECL
2535 && DECL_CONTEXT (ns) == std_node
2536 && DECL_NAME (ns)
2537 && !strcmp (IDENTIFIER_POINTER (DECL_NAME (ns)), "decimal"))
2538 {
2539 const char *n = TYPE_NAME_STRING (t);
2540 if ((strcmp (n, "decimal32") == 0)
2541 || (strcmp (n, "decimal64") == 0)
2542 || (strcmp (n, "decimal128") == 0))
2543 TYPE_TRANSPARENT_AGGR (t) = 1;
2544 }
2545 }
2546
2547 /* A non-implicit typename comes from code like:
2548
2549 template <typename T> struct A {
2550 template <typename U> struct A<T>::B ...
2551
2552 This is erroneous. */
2553 else if (TREE_CODE (t) == TYPENAME_TYPE)
2554 {
2555 error ("invalid definition of qualified type %qT", t);
2556 t = error_mark_node;
2557 }
2558
2559 if (t == error_mark_node || ! MAYBE_CLASS_TYPE_P (t))
2560 {
2561 t = make_class_type (RECORD_TYPE);
2562 pushtag (make_anon_name (), t, /*tag_scope=*/ts_current);
2563 }
2564
2565 if (TYPE_BEING_DEFINED (t))
2566 {
2567 t = make_class_type (TREE_CODE (t));
2568 pushtag (TYPE_IDENTIFIER (t), t, /*tag_scope=*/ts_current);
2569 }
2570 maybe_process_partial_specialization (t);
2571 pushclass (t);
2572 TYPE_BEING_DEFINED (t) = 1;
2573
2574 if (flag_pack_struct)
2575 {
2576 tree v;
2577 TYPE_PACKED (t) = 1;
2578 /* Even though the type is being defined for the first time
2579 here, there might have been a forward declaration, so there
2580 might be cv-qualified variants of T. */
2581 for (v = TYPE_NEXT_VARIANT (t); v; v = TYPE_NEXT_VARIANT (v))
2582 TYPE_PACKED (v) = 1;
2583 }
2584 /* Reset the interface data, at the earliest possible
2585 moment, as it might have been set via a class foo;
2586 before. */
2587 if (! TYPE_ANONYMOUS_P (t))
2588 {
2589 struct c_fileinfo *finfo = get_fileinfo (input_filename);
2590 CLASSTYPE_INTERFACE_ONLY (t) = finfo->interface_only;
2591 SET_CLASSTYPE_INTERFACE_UNKNOWN_X
2592 (t, finfo->interface_unknown);
2593 }
2594 reset_specialization();
2595
2596 /* Make a declaration for this class in its own scope. */
2597 build_self_reference ();
2598
2599 return t;
2600 }
2601
2602 /* Finish the member declaration given by DECL. */
2603
2604 void
finish_member_declaration(tree decl)2605 finish_member_declaration (tree decl)
2606 {
2607 if (decl == error_mark_node || decl == NULL_TREE)
2608 return;
2609
2610 if (decl == void_type_node)
2611 /* The COMPONENT was a friend, not a member, and so there's
2612 nothing for us to do. */
2613 return;
2614
2615 /* We should see only one DECL at a time. */
2616 gcc_assert (DECL_CHAIN (decl) == NULL_TREE);
2617
2618 /* Set up access control for DECL. */
2619 TREE_PRIVATE (decl)
2620 = (current_access_specifier == access_private_node);
2621 TREE_PROTECTED (decl)
2622 = (current_access_specifier == access_protected_node);
2623 if (TREE_CODE (decl) == TEMPLATE_DECL)
2624 {
2625 TREE_PRIVATE (DECL_TEMPLATE_RESULT (decl)) = TREE_PRIVATE (decl);
2626 TREE_PROTECTED (DECL_TEMPLATE_RESULT (decl)) = TREE_PROTECTED (decl);
2627 }
2628
2629 /* Mark the DECL as a member of the current class. */
2630 DECL_CONTEXT (decl) = current_class_type;
2631
2632 /* Check for bare parameter packs in the member variable declaration. */
2633 if (TREE_CODE (decl) == FIELD_DECL)
2634 {
2635 if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
2636 TREE_TYPE (decl) = error_mark_node;
2637 if (check_for_bare_parameter_packs (DECL_ATTRIBUTES (decl)))
2638 DECL_ATTRIBUTES (decl) = NULL_TREE;
2639 }
2640
2641 /* [dcl.link]
2642
2643 A C language linkage is ignored for the names of class members
2644 and the member function type of class member functions. */
2645 if (DECL_LANG_SPECIFIC (decl) && DECL_LANGUAGE (decl) == lang_c)
2646 SET_DECL_LANGUAGE (decl, lang_cplusplus);
2647
2648 /* Put functions on the TYPE_METHODS list and everything else on the
2649 TYPE_FIELDS list. Note that these are built up in reverse order.
2650 We reverse them (to obtain declaration order) in finish_struct. */
2651 if (TREE_CODE (decl) == FUNCTION_DECL
2652 || DECL_FUNCTION_TEMPLATE_P (decl))
2653 {
2654 /* We also need to add this function to the
2655 CLASSTYPE_METHOD_VEC. */
2656 if (add_method (current_class_type, decl, NULL_TREE))
2657 {
2658 DECL_CHAIN (decl) = TYPE_METHODS (current_class_type);
2659 TYPE_METHODS (current_class_type) = decl;
2660
2661 maybe_add_class_template_decl_list (current_class_type, decl,
2662 /*friend_p=*/0);
2663 }
2664 }
2665 /* Enter the DECL into the scope of the class. */
2666 else if (pushdecl_class_level (decl))
2667 {
2668 if (TREE_CODE (decl) == USING_DECL)
2669 {
2670 /* For now, ignore class-scope USING_DECLS, so that
2671 debugging backends do not see them. */
2672 DECL_IGNORED_P (decl) = 1;
2673 }
2674
2675 /* All TYPE_DECLs go at the end of TYPE_FIELDS. Ordinary fields
2676 go at the beginning. The reason is that lookup_field_1
2677 searches the list in order, and we want a field name to
2678 override a type name so that the "struct stat hack" will
2679 work. In particular:
2680
2681 struct S { enum E { }; int E } s;
2682 s.E = 3;
2683
2684 is valid. In addition, the FIELD_DECLs must be maintained in
2685 declaration order so that class layout works as expected.
2686 However, we don't need that order until class layout, so we
2687 save a little time by putting FIELD_DECLs on in reverse order
2688 here, and then reversing them in finish_struct_1. (We could
2689 also keep a pointer to the correct insertion points in the
2690 list.) */
2691
2692 if (TREE_CODE (decl) == TYPE_DECL)
2693 TYPE_FIELDS (current_class_type)
2694 = chainon (TYPE_FIELDS (current_class_type), decl);
2695 else
2696 {
2697 DECL_CHAIN (decl) = TYPE_FIELDS (current_class_type);
2698 TYPE_FIELDS (current_class_type) = decl;
2699 }
2700
2701 maybe_add_class_template_decl_list (current_class_type, decl,
2702 /*friend_p=*/0);
2703 }
2704
2705 if (pch_file)
2706 note_decl_for_pch (decl);
2707 }
2708
2709 /* DECL has been declared while we are building a PCH file. Perform
2710 actions that we might normally undertake lazily, but which can be
2711 performed now so that they do not have to be performed in
2712 translation units which include the PCH file. */
2713
2714 void
note_decl_for_pch(tree decl)2715 note_decl_for_pch (tree decl)
2716 {
2717 gcc_assert (pch_file);
2718
2719 /* There's a good chance that we'll have to mangle names at some
2720 point, even if only for emission in debugging information. */
2721 if ((TREE_CODE (decl) == VAR_DECL
2722 || TREE_CODE (decl) == FUNCTION_DECL)
2723 && !processing_template_decl)
2724 mangle_decl (decl);
2725 }
2726
2727 /* Finish processing a complete template declaration. The PARMS are
2728 the template parameters. */
2729
2730 void
finish_template_decl(tree parms)2731 finish_template_decl (tree parms)
2732 {
2733 if (parms)
2734 end_template_decl ();
2735 else
2736 end_specialization ();
2737 }
2738
2739 /* Finish processing a template-id (which names a type) of the form
2740 NAME < ARGS >. Return the TYPE_DECL for the type named by the
2741 template-id. If ENTERING_SCOPE is nonzero we are about to enter
2742 the scope of template-id indicated. */
2743
2744 tree
finish_template_type(tree name,tree args,int entering_scope)2745 finish_template_type (tree name, tree args, int entering_scope)
2746 {
2747 tree type;
2748
2749 type = lookup_template_class (name, args,
2750 NULL_TREE, NULL_TREE, entering_scope,
2751 tf_warning_or_error | tf_user);
2752 if (type == error_mark_node)
2753 return type;
2754 else if (CLASS_TYPE_P (type) && !alias_type_or_template_p (type))
2755 return TYPE_STUB_DECL (type);
2756 else
2757 return TYPE_NAME (type);
2758 }
2759
2760 /* Finish processing a BASE_CLASS with the indicated ACCESS_SPECIFIER.
2761 Return a TREE_LIST containing the ACCESS_SPECIFIER and the
2762 BASE_CLASS, or NULL_TREE if an error occurred. The
2763 ACCESS_SPECIFIER is one of
2764 access_{default,public,protected_private}_node. For a virtual base
2765 we set TREE_TYPE. */
2766
2767 tree
finish_base_specifier(tree base,tree access,bool virtual_p)2768 finish_base_specifier (tree base, tree access, bool virtual_p)
2769 {
2770 tree result;
2771
2772 if (base == error_mark_node)
2773 {
2774 error ("invalid base-class specification");
2775 result = NULL_TREE;
2776 }
2777 else if (! MAYBE_CLASS_TYPE_P (base))
2778 {
2779 error ("%qT is not a class type", base);
2780 result = NULL_TREE;
2781 }
2782 else
2783 {
2784 if (cp_type_quals (base) != 0)
2785 {
2786 /* DR 484: Can a base-specifier name a cv-qualified
2787 class type? */
2788 base = TYPE_MAIN_VARIANT (base);
2789 }
2790 result = build_tree_list (access, base);
2791 if (virtual_p)
2792 TREE_TYPE (result) = integer_type_node;
2793 }
2794
2795 return result;
2796 }
2797
2798 /* If FNS is a member function, a set of member functions, or a
2799 template-id referring to one or more member functions, return a
2800 BASELINK for FNS, incorporating the current access context.
2801 Otherwise, return FNS unchanged. */
2802
2803 tree
baselink_for_fns(tree fns)2804 baselink_for_fns (tree fns)
2805 {
2806 tree scope;
2807 tree cl;
2808
2809 if (BASELINK_P (fns)
2810 || error_operand_p (fns))
2811 return fns;
2812
2813 scope = ovl_scope (fns);
2814 if (!CLASS_TYPE_P (scope))
2815 return fns;
2816
2817 cl = currently_open_derived_class (scope);
2818 if (!cl)
2819 cl = scope;
2820 cl = TYPE_BINFO (cl);
2821 return build_baselink (cl, cl, fns, /*optype=*/NULL_TREE);
2822 }
2823
2824 /* Returns true iff DECL is a variable from a function outside
2825 the current one. */
2826
2827 static bool
outer_var_p(tree decl)2828 outer_var_p (tree decl)
2829 {
2830 return ((TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == PARM_DECL)
2831 && DECL_FUNCTION_SCOPE_P (decl)
2832 && DECL_CONTEXT (decl) != current_function_decl);
2833 }
2834
2835 /* As above, but also checks that DECL is automatic. */
2836
2837 static bool
outer_automatic_var_p(tree decl)2838 outer_automatic_var_p (tree decl)
2839 {
2840 return (outer_var_p (decl)
2841 && !TREE_STATIC (decl));
2842 }
2843
2844 /* ID_EXPRESSION is a representation of parsed, but unprocessed,
2845 id-expression. (See cp_parser_id_expression for details.) SCOPE,
2846 if non-NULL, is the type or namespace used to explicitly qualify
2847 ID_EXPRESSION. DECL is the entity to which that name has been
2848 resolved.
2849
2850 *CONSTANT_EXPRESSION_P is true if we are presently parsing a
2851 constant-expression. In that case, *NON_CONSTANT_EXPRESSION_P will
2852 be set to true if this expression isn't permitted in a
2853 constant-expression, but it is otherwise not set by this function.
2854 *ALLOW_NON_CONSTANT_EXPRESSION_P is true if we are parsing a
2855 constant-expression, but a non-constant expression is also
2856 permissible.
2857
2858 DONE is true if this expression is a complete postfix-expression;
2859 it is false if this expression is followed by '->', '[', '(', etc.
2860 ADDRESS_P is true iff this expression is the operand of '&'.
2861 TEMPLATE_P is true iff the qualified-id was of the form
2862 "A::template B". TEMPLATE_ARG_P is true iff this qualified name
2863 appears as a template argument.
2864
2865 If an error occurs, and it is the kind of error that might cause
2866 the parser to abort a tentative parse, *ERROR_MSG is filled in. It
2867 is the caller's responsibility to issue the message. *ERROR_MSG
2868 will be a string with static storage duration, so the caller need
2869 not "free" it.
2870
2871 Return an expression for the entity, after issuing appropriate
2872 diagnostics. This function is also responsible for transforming a
2873 reference to a non-static member into a COMPONENT_REF that makes
2874 the use of "this" explicit.
2875
2876 Upon return, *IDK will be filled in appropriately. */
2877 tree
finish_id_expression(tree id_expression,tree decl,tree scope,cp_id_kind * idk,bool integral_constant_expression_p,bool allow_non_integral_constant_expression_p,bool * non_integral_constant_expression_p,bool template_p,bool done,bool address_p,bool template_arg_p,const char ** error_msg,location_t location)2878 finish_id_expression (tree id_expression,
2879 tree decl,
2880 tree scope,
2881 cp_id_kind *idk,
2882 bool integral_constant_expression_p,
2883 bool allow_non_integral_constant_expression_p,
2884 bool *non_integral_constant_expression_p,
2885 bool template_p,
2886 bool done,
2887 bool address_p,
2888 bool template_arg_p,
2889 const char **error_msg,
2890 location_t location)
2891 {
2892 decl = strip_using_decl (decl);
2893
2894 /* Initialize the output parameters. */
2895 *idk = CP_ID_KIND_NONE;
2896 *error_msg = NULL;
2897
2898 if (id_expression == error_mark_node)
2899 return error_mark_node;
2900 /* If we have a template-id, then no further lookup is
2901 required. If the template-id was for a template-class, we
2902 will sometimes have a TYPE_DECL at this point. */
2903 else if (TREE_CODE (decl) == TEMPLATE_ID_EXPR
2904 || TREE_CODE (decl) == TYPE_DECL)
2905 ;
2906 /* Look up the name. */
2907 else
2908 {
2909 if (decl == error_mark_node)
2910 {
2911 /* Name lookup failed. */
2912 if (scope
2913 && (!TYPE_P (scope)
2914 || (!dependent_type_p (scope)
2915 && !(TREE_CODE (id_expression) == IDENTIFIER_NODE
2916 && IDENTIFIER_TYPENAME_P (id_expression)
2917 && dependent_type_p (TREE_TYPE (id_expression))))))
2918 {
2919 /* If the qualifying type is non-dependent (and the name
2920 does not name a conversion operator to a dependent
2921 type), issue an error. */
2922 qualified_name_lookup_error (scope, id_expression, decl, location);
2923 return error_mark_node;
2924 }
2925 else if (!scope)
2926 {
2927 /* It may be resolved via Koenig lookup. */
2928 *idk = CP_ID_KIND_UNQUALIFIED;
2929 return id_expression;
2930 }
2931 else
2932 decl = id_expression;
2933 }
2934 /* If DECL is a variable that would be out of scope under
2935 ANSI/ISO rules, but in scope in the ARM, name lookup
2936 will succeed. Issue a diagnostic here. */
2937 else
2938 decl = check_for_out_of_scope_variable (decl);
2939
2940 /* Remember that the name was used in the definition of
2941 the current class so that we can check later to see if
2942 the meaning would have been different after the class
2943 was entirely defined. */
2944 if (!scope && decl != error_mark_node
2945 && TREE_CODE (id_expression) == IDENTIFIER_NODE)
2946 maybe_note_name_used_in_class (id_expression, decl);
2947
2948 /* Disallow uses of local variables from containing functions, except
2949 within lambda-expressions. */
2950 if (!outer_var_p (decl)
2951 /* It's not a use (3.2) if we're in an unevaluated context. */
2952 || cp_unevaluated_operand)
2953 /* OK. */;
2954 else if (TREE_STATIC (decl))
2955 {
2956 if (processing_template_decl)
2957 /* For a use of an outer static var, return the identifier so
2958 that we'll look it up again in the instantiation. */
2959 return id_expression;
2960 }
2961 else
2962 {
2963 tree context = DECL_CONTEXT (decl);
2964 tree containing_function = current_function_decl;
2965 tree lambda_stack = NULL_TREE;
2966 tree lambda_expr = NULL_TREE;
2967 tree initializer = convert_from_reference (decl);
2968
2969 /* Mark it as used now even if the use is ill-formed. */
2970 mark_used (decl);
2971
2972 /* Core issue 696: "[At the July 2009 meeting] the CWG expressed
2973 support for an approach in which a reference to a local
2974 [constant] automatic variable in a nested class or lambda body
2975 would enter the expression as an rvalue, which would reduce
2976 the complexity of the problem"
2977
2978 FIXME update for final resolution of core issue 696. */
2979 if (decl_constant_var_p (decl))
2980 {
2981 if (processing_template_decl)
2982 /* In a template, the constant value may not be in a usable
2983 form, so look it up again at instantiation time. */
2984 return id_expression;
2985 else
2986 return integral_constant_value (decl);
2987 }
2988
2989 /* If we are in a lambda function, we can move out until we hit
2990 1. the context,
2991 2. a non-lambda function, or
2992 3. a non-default capturing lambda function. */
2993 while (context != containing_function
2994 && LAMBDA_FUNCTION_P (containing_function))
2995 {
2996 lambda_expr = CLASSTYPE_LAMBDA_EXPR
2997 (DECL_CONTEXT (containing_function));
2998
2999 if (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda_expr)
3000 == CPLD_NONE)
3001 break;
3002
3003 lambda_stack = tree_cons (NULL_TREE,
3004 lambda_expr,
3005 lambda_stack);
3006
3007 containing_function
3008 = decl_function_context (containing_function);
3009 }
3010
3011 if (context == containing_function)
3012 {
3013 decl = add_default_capture (lambda_stack,
3014 /*id=*/DECL_NAME (decl),
3015 initializer);
3016 }
3017 else if (lambda_expr)
3018 {
3019 error ("%qD is not captured", decl);
3020 return error_mark_node;
3021 }
3022 else
3023 {
3024 error (TREE_CODE (decl) == VAR_DECL
3025 ? G_("use of %<auto%> variable from containing function")
3026 : G_("use of parameter from containing function"));
3027 error (" %q+#D declared here", decl);
3028 return error_mark_node;
3029 }
3030 }
3031
3032 /* Also disallow uses of function parameters outside the function
3033 body, except inside an unevaluated context (i.e. decltype). */
3034 if (TREE_CODE (decl) == PARM_DECL
3035 && DECL_CONTEXT (decl) == NULL_TREE
3036 && !cp_unevaluated_operand)
3037 {
3038 error ("use of parameter %qD outside function body", decl);
3039 return error_mark_node;
3040 }
3041 }
3042
3043 /* If we didn't find anything, or what we found was a type,
3044 then this wasn't really an id-expression. */
3045 if (TREE_CODE (decl) == TEMPLATE_DECL
3046 && !DECL_FUNCTION_TEMPLATE_P (decl))
3047 {
3048 *error_msg = "missing template arguments";
3049 return error_mark_node;
3050 }
3051 else if (TREE_CODE (decl) == TYPE_DECL
3052 || TREE_CODE (decl) == NAMESPACE_DECL)
3053 {
3054 *error_msg = "expected primary-expression";
3055 return error_mark_node;
3056 }
3057
3058 /* If the name resolved to a template parameter, there is no
3059 need to look it up again later. */
3060 if ((TREE_CODE (decl) == CONST_DECL && DECL_TEMPLATE_PARM_P (decl))
3061 || TREE_CODE (decl) == TEMPLATE_PARM_INDEX)
3062 {
3063 tree r;
3064
3065 *idk = CP_ID_KIND_NONE;
3066 if (TREE_CODE (decl) == TEMPLATE_PARM_INDEX)
3067 decl = TEMPLATE_PARM_DECL (decl);
3068 r = convert_from_reference (DECL_INITIAL (decl));
3069
3070 if (integral_constant_expression_p
3071 && !dependent_type_p (TREE_TYPE (decl))
3072 && !(INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (r))))
3073 {
3074 if (!allow_non_integral_constant_expression_p)
3075 error ("template parameter %qD of type %qT is not allowed in "
3076 "an integral constant expression because it is not of "
3077 "integral or enumeration type", decl, TREE_TYPE (decl));
3078 *non_integral_constant_expression_p = true;
3079 }
3080 return r;
3081 }
3082 /* Similarly, we resolve enumeration constants to their
3083 underlying values. */
3084 else if (TREE_CODE (decl) == CONST_DECL)
3085 {
3086 *idk = CP_ID_KIND_NONE;
3087 if (!processing_template_decl)
3088 {
3089 used_types_insert (TREE_TYPE (decl));
3090 return DECL_INITIAL (decl);
3091 }
3092 return decl;
3093 }
3094 else
3095 {
3096 bool dependent_p;
3097
3098 /* If the declaration was explicitly qualified indicate
3099 that. The semantics of `A::f(3)' are different than
3100 `f(3)' if `f' is virtual. */
3101 *idk = (scope
3102 ? CP_ID_KIND_QUALIFIED
3103 : (TREE_CODE (decl) == TEMPLATE_ID_EXPR
3104 ? CP_ID_KIND_TEMPLATE_ID
3105 : CP_ID_KIND_UNQUALIFIED));
3106
3107
3108 /* [temp.dep.expr]
3109
3110 An id-expression is type-dependent if it contains an
3111 identifier that was declared with a dependent type.
3112
3113 The standard is not very specific about an id-expression that
3114 names a set of overloaded functions. What if some of them
3115 have dependent types and some of them do not? Presumably,
3116 such a name should be treated as a dependent name. */
3117 /* Assume the name is not dependent. */
3118 dependent_p = false;
3119 if (!processing_template_decl)
3120 /* No names are dependent outside a template. */
3121 ;
3122 /* A template-id where the name of the template was not resolved
3123 is definitely dependent. */
3124 else if (TREE_CODE (decl) == TEMPLATE_ID_EXPR
3125 && (TREE_CODE (TREE_OPERAND (decl, 0))
3126 == IDENTIFIER_NODE))
3127 dependent_p = true;
3128 /* For anything except an overloaded function, just check its
3129 type. */
3130 else if (!is_overloaded_fn (decl))
3131 dependent_p
3132 = dependent_type_p (TREE_TYPE (decl));
3133 /* For a set of overloaded functions, check each of the
3134 functions. */
3135 else
3136 {
3137 tree fns = decl;
3138
3139 if (BASELINK_P (fns))
3140 fns = BASELINK_FUNCTIONS (fns);
3141
3142 /* For a template-id, check to see if the template
3143 arguments are dependent. */
3144 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
3145 {
3146 tree args = TREE_OPERAND (fns, 1);
3147 dependent_p = any_dependent_template_arguments_p (args);
3148 /* The functions are those referred to by the
3149 template-id. */
3150 fns = TREE_OPERAND (fns, 0);
3151 }
3152
3153 /* If there are no dependent template arguments, go through
3154 the overloaded functions. */
3155 while (fns && !dependent_p)
3156 {
3157 tree fn = OVL_CURRENT (fns);
3158
3159 /* Member functions of dependent classes are
3160 dependent. */
3161 if (TREE_CODE (fn) == FUNCTION_DECL
3162 && type_dependent_expression_p (fn))
3163 dependent_p = true;
3164 else if (TREE_CODE (fn) == TEMPLATE_DECL
3165 && dependent_template_p (fn))
3166 dependent_p = true;
3167
3168 fns = OVL_NEXT (fns);
3169 }
3170 }
3171
3172 /* If the name was dependent on a template parameter, we will
3173 resolve the name at instantiation time. */
3174 if (dependent_p)
3175 {
3176 /* Create a SCOPE_REF for qualified names, if the scope is
3177 dependent. */
3178 if (scope)
3179 {
3180 if (TYPE_P (scope))
3181 {
3182 if (address_p && done)
3183 decl = finish_qualified_id_expr (scope, decl,
3184 done, address_p,
3185 template_p,
3186 template_arg_p);
3187 else
3188 {
3189 tree type = NULL_TREE;
3190 if (DECL_P (decl) && !dependent_scope_p (scope))
3191 type = TREE_TYPE (decl);
3192 decl = build_qualified_name (type,
3193 scope,
3194 id_expression,
3195 template_p);
3196 }
3197 }
3198 if (TREE_TYPE (decl))
3199 decl = convert_from_reference (decl);
3200 return decl;
3201 }
3202 /* A TEMPLATE_ID already contains all the information we
3203 need. */
3204 if (TREE_CODE (id_expression) == TEMPLATE_ID_EXPR)
3205 return id_expression;
3206 *idk = CP_ID_KIND_UNQUALIFIED_DEPENDENT;
3207 /* If we found a variable, then name lookup during the
3208 instantiation will always resolve to the same VAR_DECL
3209 (or an instantiation thereof). */
3210 if (TREE_CODE (decl) == VAR_DECL
3211 || TREE_CODE (decl) == PARM_DECL)
3212 {
3213 mark_used (decl);
3214 return convert_from_reference (decl);
3215 }
3216 /* The same is true for FIELD_DECL, but we also need to
3217 make sure that the syntax is correct. */
3218 else if (TREE_CODE (decl) == FIELD_DECL)
3219 {
3220 /* Since SCOPE is NULL here, this is an unqualified name.
3221 Access checking has been performed during name lookup
3222 already. Turn off checking to avoid duplicate errors. */
3223 push_deferring_access_checks (dk_no_check);
3224 decl = finish_non_static_data_member
3225 (decl, NULL_TREE,
3226 /*qualifying_scope=*/NULL_TREE);
3227 pop_deferring_access_checks ();
3228 return decl;
3229 }
3230 return id_expression;
3231 }
3232
3233 if (TREE_CODE (decl) == NAMESPACE_DECL)
3234 {
3235 error ("use of namespace %qD as expression", decl);
3236 return error_mark_node;
3237 }
3238 else if (DECL_CLASS_TEMPLATE_P (decl))
3239 {
3240 error ("use of class template %qT as expression", decl);
3241 return error_mark_node;
3242 }
3243 else if (TREE_CODE (decl) == TREE_LIST)
3244 {
3245 /* Ambiguous reference to base members. */
3246 error ("request for member %qD is ambiguous in "
3247 "multiple inheritance lattice", id_expression);
3248 print_candidates (decl);
3249 return error_mark_node;
3250 }
3251
3252 /* Mark variable-like entities as used. Functions are similarly
3253 marked either below or after overload resolution. */
3254 if (TREE_CODE (decl) == VAR_DECL
3255 || TREE_CODE (decl) == PARM_DECL
3256 || TREE_CODE (decl) == RESULT_DECL)
3257 mark_used (decl);
3258
3259 /* Only certain kinds of names are allowed in constant
3260 expression. Enumerators and template parameters have already
3261 been handled above. */
3262 if (! error_operand_p (decl)
3263 && integral_constant_expression_p
3264 && ! decl_constant_var_p (decl)
3265 && ! builtin_valid_in_constant_expr_p (decl))
3266 {
3267 if (!allow_non_integral_constant_expression_p)
3268 {
3269 error ("%qD cannot appear in a constant-expression", decl);
3270 return error_mark_node;
3271 }
3272 *non_integral_constant_expression_p = true;
3273 }
3274
3275 if (scope)
3276 {
3277 decl = (adjust_result_of_qualified_name_lookup
3278 (decl, scope, current_nonlambda_class_type()));
3279
3280 if (TREE_CODE (decl) == FUNCTION_DECL)
3281 mark_used (decl);
3282
3283 if (TREE_CODE (decl) == FIELD_DECL || BASELINK_P (decl))
3284 decl = finish_qualified_id_expr (scope,
3285 decl,
3286 done,
3287 address_p,
3288 template_p,
3289 template_arg_p);
3290 else
3291 {
3292 tree r = convert_from_reference (decl);
3293
3294 /* In a template, return a SCOPE_REF for most qualified-ids
3295 so that we can check access at instantiation time. But if
3296 we're looking at a member of the current instantiation, we
3297 know we have access and building up the SCOPE_REF confuses
3298 non-type template argument handling. */
3299 if (processing_template_decl && TYPE_P (scope)
3300 && !currently_open_class (scope))
3301 r = build_qualified_name (TREE_TYPE (r),
3302 scope, decl,
3303 template_p);
3304 decl = r;
3305 }
3306 }
3307 else if (TREE_CODE (decl) == FIELD_DECL)
3308 {
3309 /* Since SCOPE is NULL here, this is an unqualified name.
3310 Access checking has been performed during name lookup
3311 already. Turn off checking to avoid duplicate errors. */
3312 push_deferring_access_checks (dk_no_check);
3313 decl = finish_non_static_data_member (decl, NULL_TREE,
3314 /*qualifying_scope=*/NULL_TREE);
3315 pop_deferring_access_checks ();
3316 }
3317 else if (is_overloaded_fn (decl))
3318 {
3319 tree first_fn;
3320
3321 first_fn = get_first_fn (decl);
3322 if (TREE_CODE (first_fn) == TEMPLATE_DECL)
3323 first_fn = DECL_TEMPLATE_RESULT (first_fn);
3324
3325 if (!really_overloaded_fn (decl)
3326 && !mark_used (first_fn))
3327 return error_mark_node;
3328
3329 if (!template_arg_p
3330 && TREE_CODE (first_fn) == FUNCTION_DECL
3331 && DECL_FUNCTION_MEMBER_P (first_fn)
3332 && !shared_member_p (decl))
3333 {
3334 /* A set of member functions. */
3335 decl = maybe_dummy_object (DECL_CONTEXT (first_fn), 0);
3336 return finish_class_member_access_expr (decl, id_expression,
3337 /*template_p=*/false,
3338 tf_warning_or_error);
3339 }
3340
3341 decl = baselink_for_fns (decl);
3342 }
3343 else
3344 {
3345 if (DECL_P (decl) && DECL_NONLOCAL (decl)
3346 && DECL_CLASS_SCOPE_P (decl))
3347 {
3348 tree context = context_for_name_lookup (decl);
3349 if (context != current_class_type)
3350 {
3351 tree path = currently_open_derived_class (context);
3352 perform_or_defer_access_check (TYPE_BINFO (path),
3353 decl, decl);
3354 }
3355 }
3356
3357 decl = convert_from_reference (decl);
3358 }
3359 }
3360
3361 if (TREE_DEPRECATED (decl))
3362 warn_deprecated_use (decl, NULL_TREE);
3363
3364 return decl;
3365 }
3366
3367 /* Implement the __typeof keyword: Return the type of EXPR, suitable for
3368 use as a type-specifier. */
3369
3370 tree
finish_typeof(tree expr)3371 finish_typeof (tree expr)
3372 {
3373 tree type;
3374
3375 if (type_dependent_expression_p (expr))
3376 {
3377 type = cxx_make_type (TYPEOF_TYPE);
3378 TYPEOF_TYPE_EXPR (type) = expr;
3379 SET_TYPE_STRUCTURAL_EQUALITY (type);
3380
3381 return type;
3382 }
3383
3384 expr = mark_type_use (expr);
3385
3386 type = unlowered_expr_type (expr);
3387
3388 if (!type || type == unknown_type_node)
3389 {
3390 error ("type of %qE is unknown", expr);
3391 return error_mark_node;
3392 }
3393
3394 return type;
3395 }
3396
3397 /* Implement the __underlying_type keyword: Return the underlying
3398 type of TYPE, suitable for use as a type-specifier. */
3399
3400 tree
finish_underlying_type(tree type)3401 finish_underlying_type (tree type)
3402 {
3403 tree underlying_type;
3404
3405 if (processing_template_decl)
3406 {
3407 underlying_type = cxx_make_type (UNDERLYING_TYPE);
3408 UNDERLYING_TYPE_TYPE (underlying_type) = type;
3409 SET_TYPE_STRUCTURAL_EQUALITY (underlying_type);
3410
3411 return underlying_type;
3412 }
3413
3414 complete_type (type);
3415
3416 if (TREE_CODE (type) != ENUMERAL_TYPE)
3417 {
3418 error ("%qT is not an enumeration type", type);
3419 return error_mark_node;
3420 }
3421
3422 underlying_type = ENUM_UNDERLYING_TYPE (type);
3423
3424 /* Fixup necessary in this case because ENUM_UNDERLYING_TYPE
3425 includes TYPE_MIN_VALUE and TYPE_MAX_VALUE information.
3426 See finish_enum_value_list for details. */
3427 if (!ENUM_FIXED_UNDERLYING_TYPE_P (type))
3428 underlying_type
3429 = c_common_type_for_mode (TYPE_MODE (underlying_type),
3430 TYPE_UNSIGNED (underlying_type));
3431
3432 return underlying_type;
3433 }
3434
3435 /* Implement the __direct_bases keyword: Return the direct base classes
3436 of type */
3437
3438 tree
calculate_direct_bases(tree type)3439 calculate_direct_bases (tree type)
3440 {
3441 VEC(tree, gc) *vector = make_tree_vector();
3442 tree bases_vec = NULL_TREE;
3443 VEC(tree, none) *base_binfos;
3444 tree binfo;
3445 unsigned i;
3446
3447 complete_type (type);
3448
3449 if (!NON_UNION_CLASS_TYPE_P (type))
3450 return make_tree_vec (0);
3451
3452 base_binfos = BINFO_BASE_BINFOS (TYPE_BINFO (type));
3453
3454 /* Virtual bases are initialized first */
3455 for (i = 0; VEC_iterate (tree, base_binfos, i, binfo); i++)
3456 {
3457 if (BINFO_VIRTUAL_P (binfo))
3458 {
3459 VEC_safe_push (tree, gc, vector, binfo);
3460 }
3461 }
3462
3463 /* Now non-virtuals */
3464 for (i = 0; VEC_iterate (tree, base_binfos, i, binfo); i++)
3465 {
3466 if (!BINFO_VIRTUAL_P (binfo))
3467 {
3468 VEC_safe_push (tree, gc, vector, binfo);
3469 }
3470 }
3471
3472
3473 bases_vec = make_tree_vec (VEC_length (tree, vector));
3474
3475 for (i = 0; i < VEC_length (tree, vector); ++i)
3476 {
3477 TREE_VEC_ELT (bases_vec, i) = BINFO_TYPE (VEC_index (tree, vector, i));
3478 }
3479 return bases_vec;
3480 }
3481
3482 /* Implement the __bases keyword: Return the base classes
3483 of type */
3484
3485 /* Find morally non-virtual base classes by walking binfo hierarchy */
3486 /* Virtual base classes are handled separately in finish_bases */
3487
3488 static tree
dfs_calculate_bases_pre(tree binfo,ATTRIBUTE_UNUSED void * data_)3489 dfs_calculate_bases_pre (tree binfo, ATTRIBUTE_UNUSED void *data_)
3490 {
3491 /* Don't walk bases of virtual bases */
3492 return BINFO_VIRTUAL_P (binfo) ? dfs_skip_bases : NULL_TREE;
3493 }
3494
3495 static tree
dfs_calculate_bases_post(tree binfo,void * data_)3496 dfs_calculate_bases_post (tree binfo, void *data_)
3497 {
3498 VEC(tree, gc) **data = (VEC(tree, gc) **) data_;
3499 if (!BINFO_VIRTUAL_P (binfo))
3500 {
3501 VEC_safe_push (tree, gc, *data, BINFO_TYPE (binfo));
3502 }
3503 return NULL_TREE;
3504 }
3505
3506 /* Calculates the morally non-virtual base classes of a class */
VEC(tree,gc)3507 static VEC(tree, gc) *
3508 calculate_bases_helper (tree type)
3509 {
3510 VEC(tree, gc) *vector = make_tree_vector();
3511
3512 /* Now add non-virtual base classes in order of construction */
3513 dfs_walk_all (TYPE_BINFO (type),
3514 dfs_calculate_bases_pre, dfs_calculate_bases_post, &vector);
3515 return vector;
3516 }
3517
3518 tree
calculate_bases(tree type)3519 calculate_bases (tree type)
3520 {
3521 VEC(tree, gc) *vector = make_tree_vector();
3522 tree bases_vec = NULL_TREE;
3523 unsigned i;
3524 VEC(tree, gc) *vbases;
3525 VEC(tree, gc) *nonvbases;
3526 tree binfo;
3527
3528 complete_type (type);
3529
3530 if (!NON_UNION_CLASS_TYPE_P (type))
3531 return make_tree_vec (0);
3532
3533 /* First go through virtual base classes */
3534 for (vbases = CLASSTYPE_VBASECLASSES (type), i = 0;
3535 VEC_iterate (tree, vbases, i, binfo); i++)
3536 {
3537 VEC(tree, gc) *vbase_bases = calculate_bases_helper (BINFO_TYPE (binfo));
3538 VEC_safe_splice (tree, gc, vector, vbase_bases);
3539 release_tree_vector (vbase_bases);
3540 }
3541
3542 /* Now for the non-virtual bases */
3543 nonvbases = calculate_bases_helper (type);
3544 VEC_safe_splice (tree, gc, vector, nonvbases);
3545 release_tree_vector (nonvbases);
3546
3547 /* Last element is entire class, so don't copy */
3548 bases_vec = make_tree_vec (VEC_length (tree, vector) - 1);
3549
3550 for (i = 0; i < VEC_length (tree, vector) - 1; ++i)
3551 {
3552 TREE_VEC_ELT (bases_vec, i) = VEC_index (tree, vector, i);
3553 }
3554 release_tree_vector (vector);
3555 return bases_vec;
3556 }
3557
3558 tree
finish_bases(tree type,bool direct)3559 finish_bases (tree type, bool direct)
3560 {
3561 tree bases = NULL_TREE;
3562
3563 if (!processing_template_decl)
3564 {
3565 /* Parameter packs can only be used in templates */
3566 error ("Parameter pack __bases only valid in template declaration");
3567 return error_mark_node;
3568 }
3569
3570 bases = cxx_make_type (BASES);
3571 BASES_TYPE (bases) = type;
3572 BASES_DIRECT (bases) = direct;
3573 SET_TYPE_STRUCTURAL_EQUALITY (bases);
3574
3575 return bases;
3576 }
3577
3578 /* Perform C++-specific checks for __builtin_offsetof before calling
3579 fold_offsetof. */
3580
3581 tree
finish_offsetof(tree expr)3582 finish_offsetof (tree expr)
3583 {
3584 if (TREE_CODE (expr) == PSEUDO_DTOR_EXPR)
3585 {
3586 error ("cannot apply %<offsetof%> to destructor %<~%T%>",
3587 TREE_OPERAND (expr, 2));
3588 return error_mark_node;
3589 }
3590 if (TREE_CODE (TREE_TYPE (expr)) == FUNCTION_TYPE
3591 || TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE
3592 || TREE_TYPE (expr) == unknown_type_node)
3593 {
3594 if (TREE_CODE (expr) == COMPONENT_REF
3595 || TREE_CODE (expr) == COMPOUND_EXPR)
3596 expr = TREE_OPERAND (expr, 1);
3597 error ("cannot apply %<offsetof%> to member function %qD", expr);
3598 return error_mark_node;
3599 }
3600 if (REFERENCE_REF_P (expr))
3601 expr = TREE_OPERAND (expr, 0);
3602 if (TREE_CODE (expr) == COMPONENT_REF)
3603 {
3604 tree object = TREE_OPERAND (expr, 0);
3605 if (!complete_type_or_else (TREE_TYPE (object), object))
3606 return error_mark_node;
3607 }
3608 return fold_offsetof (expr);
3609 }
3610
3611 /* Replace the AGGR_INIT_EXPR at *TP with an equivalent CALL_EXPR. This
3612 function is broken out from the above for the benefit of the tree-ssa
3613 project. */
3614
3615 void
simplify_aggr_init_expr(tree * tp)3616 simplify_aggr_init_expr (tree *tp)
3617 {
3618 tree aggr_init_expr = *tp;
3619
3620 /* Form an appropriate CALL_EXPR. */
3621 tree fn = AGGR_INIT_EXPR_FN (aggr_init_expr);
3622 tree slot = AGGR_INIT_EXPR_SLOT (aggr_init_expr);
3623 tree type = TREE_TYPE (slot);
3624
3625 tree call_expr;
3626 enum style_t { ctor, arg, pcc } style;
3627
3628 if (AGGR_INIT_VIA_CTOR_P (aggr_init_expr))
3629 style = ctor;
3630 #ifdef PCC_STATIC_STRUCT_RETURN
3631 else if (1)
3632 style = pcc;
3633 #endif
3634 else
3635 {
3636 gcc_assert (TREE_ADDRESSABLE (type));
3637 style = arg;
3638 }
3639
3640 call_expr = build_call_array_loc (input_location,
3641 TREE_TYPE (TREE_TYPE (TREE_TYPE (fn))),
3642 fn,
3643 aggr_init_expr_nargs (aggr_init_expr),
3644 AGGR_INIT_EXPR_ARGP (aggr_init_expr));
3645 TREE_NOTHROW (call_expr) = TREE_NOTHROW (aggr_init_expr);
3646
3647 if (style == ctor)
3648 {
3649 /* Replace the first argument to the ctor with the address of the
3650 slot. */
3651 cxx_mark_addressable (slot);
3652 CALL_EXPR_ARG (call_expr, 0) =
3653 build1 (ADDR_EXPR, build_pointer_type (type), slot);
3654 }
3655 else if (style == arg)
3656 {
3657 /* Just mark it addressable here, and leave the rest to
3658 expand_call{,_inline}. */
3659 cxx_mark_addressable (slot);
3660 CALL_EXPR_RETURN_SLOT_OPT (call_expr) = true;
3661 call_expr = build2 (INIT_EXPR, TREE_TYPE (call_expr), slot, call_expr);
3662 }
3663 else if (style == pcc)
3664 {
3665 /* If we're using the non-reentrant PCC calling convention, then we
3666 need to copy the returned value out of the static buffer into the
3667 SLOT. */
3668 push_deferring_access_checks (dk_no_check);
3669 call_expr = build_aggr_init (slot, call_expr,
3670 DIRECT_BIND | LOOKUP_ONLYCONVERTING,
3671 tf_warning_or_error);
3672 pop_deferring_access_checks ();
3673 call_expr = build2 (COMPOUND_EXPR, TREE_TYPE (slot), call_expr, slot);
3674 }
3675
3676 if (AGGR_INIT_ZERO_FIRST (aggr_init_expr))
3677 {
3678 tree init = build_zero_init (type, NULL_TREE,
3679 /*static_storage_p=*/false);
3680 init = build2 (INIT_EXPR, void_type_node, slot, init);
3681 call_expr = build2 (COMPOUND_EXPR, TREE_TYPE (call_expr),
3682 init, call_expr);
3683 }
3684
3685 *tp = call_expr;
3686 }
3687
3688 /* Emit all thunks to FN that should be emitted when FN is emitted. */
3689
3690 void
emit_associated_thunks(tree fn)3691 emit_associated_thunks (tree fn)
3692 {
3693 /* When we use vcall offsets, we emit thunks with the virtual
3694 functions to which they thunk. The whole point of vcall offsets
3695 is so that you can know statically the entire set of thunks that
3696 will ever be needed for a given virtual function, thereby
3697 enabling you to output all the thunks with the function itself. */
3698 if (DECL_VIRTUAL_P (fn)
3699 /* Do not emit thunks for extern template instantiations. */
3700 && ! DECL_REALLY_EXTERN (fn))
3701 {
3702 tree thunk;
3703
3704 for (thunk = DECL_THUNKS (fn); thunk; thunk = DECL_CHAIN (thunk))
3705 {
3706 if (!THUNK_ALIAS (thunk))
3707 {
3708 use_thunk (thunk, /*emit_p=*/1);
3709 if (DECL_RESULT_THUNK_P (thunk))
3710 {
3711 tree probe;
3712
3713 for (probe = DECL_THUNKS (thunk);
3714 probe; probe = DECL_CHAIN (probe))
3715 use_thunk (probe, /*emit_p=*/1);
3716 }
3717 }
3718 else
3719 gcc_assert (!DECL_THUNKS (thunk));
3720 }
3721 }
3722 }
3723
3724 /* Returns true iff FUN is an instantiation of a constexpr function
3725 template. */
3726
3727 static inline bool
is_instantiation_of_constexpr(tree fun)3728 is_instantiation_of_constexpr (tree fun)
3729 {
3730 return (DECL_TEMPLOID_INSTANTIATION (fun)
3731 && DECL_DECLARED_CONSTEXPR_P (DECL_TEMPLATE_RESULT
3732 (DECL_TI_TEMPLATE (fun))));
3733 }
3734
3735 /* Generate RTL for FN. */
3736
3737 bool
expand_or_defer_fn_1(tree fn)3738 expand_or_defer_fn_1 (tree fn)
3739 {
3740 /* When the parser calls us after finishing the body of a template
3741 function, we don't really want to expand the body. */
3742 if (processing_template_decl)
3743 {
3744 /* Normally, collection only occurs in rest_of_compilation. So,
3745 if we don't collect here, we never collect junk generated
3746 during the processing of templates until we hit a
3747 non-template function. It's not safe to do this inside a
3748 nested class, though, as the parser may have local state that
3749 is not a GC root. */
3750 if (!function_depth)
3751 ggc_collect ();
3752 return false;
3753 }
3754
3755 gcc_assert (DECL_SAVED_TREE (fn));
3756
3757 /* If this is a constructor or destructor body, we have to clone
3758 it. */
3759 if (maybe_clone_body (fn))
3760 {
3761 /* We don't want to process FN again, so pretend we've written
3762 it out, even though we haven't. */
3763 TREE_ASM_WRITTEN (fn) = 1;
3764 /* If this is an instantiation of a constexpr function, keep
3765 DECL_SAVED_TREE for explain_invalid_constexpr_fn. */
3766 if (!is_instantiation_of_constexpr (fn))
3767 DECL_SAVED_TREE (fn) = NULL_TREE;
3768 return false;
3769 }
3770
3771 /* We make a decision about linkage for these functions at the end
3772 of the compilation. Until that point, we do not want the back
3773 end to output them -- but we do want it to see the bodies of
3774 these functions so that it can inline them as appropriate. */
3775 if (DECL_DECLARED_INLINE_P (fn) || DECL_IMPLICIT_INSTANTIATION (fn))
3776 {
3777 if (DECL_INTERFACE_KNOWN (fn))
3778 /* We've already made a decision as to how this function will
3779 be handled. */;
3780 else if (!at_eof)
3781 {
3782 DECL_EXTERNAL (fn) = 1;
3783 DECL_NOT_REALLY_EXTERN (fn) = 1;
3784 note_vague_linkage_fn (fn);
3785 /* A non-template inline function with external linkage will
3786 always be COMDAT. As we must eventually determine the
3787 linkage of all functions, and as that causes writes to
3788 the data mapped in from the PCH file, it's advantageous
3789 to mark the functions at this point. */
3790 if (!DECL_IMPLICIT_INSTANTIATION (fn))
3791 {
3792 /* This function must have external linkage, as
3793 otherwise DECL_INTERFACE_KNOWN would have been
3794 set. */
3795 gcc_assert (TREE_PUBLIC (fn));
3796 comdat_linkage (fn);
3797 DECL_INTERFACE_KNOWN (fn) = 1;
3798 }
3799 }
3800 else
3801 import_export_decl (fn);
3802
3803 /* If the user wants us to keep all inline functions, then mark
3804 this function as needed so that finish_file will make sure to
3805 output it later. Similarly, all dllexport'd functions must
3806 be emitted; there may be callers in other DLLs. */
3807 if ((flag_keep_inline_functions
3808 && DECL_DECLARED_INLINE_P (fn)
3809 && !DECL_REALLY_EXTERN (fn))
3810 || (flag_keep_inline_dllexport
3811 && lookup_attribute ("dllexport", DECL_ATTRIBUTES (fn))))
3812 {
3813 mark_needed (fn);
3814 DECL_EXTERNAL (fn) = 0;
3815 }
3816 }
3817
3818 /* There's no reason to do any of the work here if we're only doing
3819 semantic analysis; this code just generates RTL. */
3820 if (flag_syntax_only)
3821 return false;
3822
3823 return true;
3824 }
3825
3826 void
expand_or_defer_fn(tree fn)3827 expand_or_defer_fn (tree fn)
3828 {
3829 if (expand_or_defer_fn_1 (fn))
3830 {
3831 function_depth++;
3832
3833 /* Expand or defer, at the whim of the compilation unit manager. */
3834 cgraph_finalize_function (fn, function_depth > 1);
3835 emit_associated_thunks (fn);
3836
3837 function_depth--;
3838 }
3839 }
3840
3841 struct nrv_data
3842 {
3843 tree var;
3844 tree result;
3845 htab_t visited;
3846 };
3847
3848 /* Helper function for walk_tree, used by finalize_nrv below. */
3849
3850 static tree
finalize_nrv_r(tree * tp,int * walk_subtrees,void * data)3851 finalize_nrv_r (tree* tp, int* walk_subtrees, void* data)
3852 {
3853 struct nrv_data *dp = (struct nrv_data *)data;
3854 void **slot;
3855
3856 /* No need to walk into types. There wouldn't be any need to walk into
3857 non-statements, except that we have to consider STMT_EXPRs. */
3858 if (TYPE_P (*tp))
3859 *walk_subtrees = 0;
3860 /* Change all returns to just refer to the RESULT_DECL; this is a nop,
3861 but differs from using NULL_TREE in that it indicates that we care
3862 about the value of the RESULT_DECL. */
3863 else if (TREE_CODE (*tp) == RETURN_EXPR)
3864 TREE_OPERAND (*tp, 0) = dp->result;
3865 /* Change all cleanups for the NRV to only run when an exception is
3866 thrown. */
3867 else if (TREE_CODE (*tp) == CLEANUP_STMT
3868 && CLEANUP_DECL (*tp) == dp->var)
3869 CLEANUP_EH_ONLY (*tp) = 1;
3870 /* Replace the DECL_EXPR for the NRV with an initialization of the
3871 RESULT_DECL, if needed. */
3872 else if (TREE_CODE (*tp) == DECL_EXPR
3873 && DECL_EXPR_DECL (*tp) == dp->var)
3874 {
3875 tree init;
3876 if (DECL_INITIAL (dp->var)
3877 && DECL_INITIAL (dp->var) != error_mark_node)
3878 init = build2 (INIT_EXPR, void_type_node, dp->result,
3879 DECL_INITIAL (dp->var));
3880 else
3881 init = build_empty_stmt (EXPR_LOCATION (*tp));
3882 DECL_INITIAL (dp->var) = NULL_TREE;
3883 SET_EXPR_LOCATION (init, EXPR_LOCATION (*tp));
3884 *tp = init;
3885 }
3886 /* And replace all uses of the NRV with the RESULT_DECL. */
3887 else if (*tp == dp->var)
3888 *tp = dp->result;
3889
3890 /* Avoid walking into the same tree more than once. Unfortunately, we
3891 can't just use walk_tree_without duplicates because it would only call
3892 us for the first occurrence of dp->var in the function body. */
3893 slot = htab_find_slot (dp->visited, *tp, INSERT);
3894 if (*slot)
3895 *walk_subtrees = 0;
3896 else
3897 *slot = *tp;
3898
3899 /* Keep iterating. */
3900 return NULL_TREE;
3901 }
3902
3903 /* Called from finish_function to implement the named return value
3904 optimization by overriding all the RETURN_EXPRs and pertinent
3905 CLEANUP_STMTs and replacing all occurrences of VAR with RESULT, the
3906 RESULT_DECL for the function. */
3907
3908 void
finalize_nrv(tree * tp,tree var,tree result)3909 finalize_nrv (tree *tp, tree var, tree result)
3910 {
3911 struct nrv_data data;
3912
3913 /* Copy name from VAR to RESULT. */
3914 DECL_NAME (result) = DECL_NAME (var);
3915 /* Don't forget that we take its address. */
3916 TREE_ADDRESSABLE (result) = TREE_ADDRESSABLE (var);
3917 /* Finally set DECL_VALUE_EXPR to avoid assigning
3918 a stack slot at -O0 for the original var and debug info
3919 uses RESULT location for VAR. */
3920 SET_DECL_VALUE_EXPR (var, result);
3921 DECL_HAS_VALUE_EXPR_P (var) = 1;
3922
3923 data.var = var;
3924 data.result = result;
3925 data.visited = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL);
3926 cp_walk_tree (tp, finalize_nrv_r, &data, 0);
3927 htab_delete (data.visited);
3928 }
3929
3930 /* Create CP_OMP_CLAUSE_INFO for clause C. Returns true if it is invalid. */
3931
3932 bool
cxx_omp_create_clause_info(tree c,tree type,bool need_default_ctor,bool need_copy_ctor,bool need_copy_assignment)3933 cxx_omp_create_clause_info (tree c, tree type, bool need_default_ctor,
3934 bool need_copy_ctor, bool need_copy_assignment)
3935 {
3936 int save_errorcount = errorcount;
3937 tree info, t;
3938
3939 /* Always allocate 3 elements for simplicity. These are the
3940 function decls for the ctor, dtor, and assignment op.
3941 This layout is known to the three lang hooks,
3942 cxx_omp_clause_default_init, cxx_omp_clause_copy_init,
3943 and cxx_omp_clause_assign_op. */
3944 info = make_tree_vec (3);
3945 CP_OMP_CLAUSE_INFO (c) = info;
3946
3947 if (need_default_ctor || need_copy_ctor)
3948 {
3949 if (need_default_ctor)
3950 t = get_default_ctor (type);
3951 else
3952 t = get_copy_ctor (type, tf_warning_or_error);
3953
3954 if (t && !trivial_fn_p (t))
3955 TREE_VEC_ELT (info, 0) = t;
3956 }
3957
3958 if ((need_default_ctor || need_copy_ctor)
3959 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
3960 TREE_VEC_ELT (info, 1) = get_dtor (type, tf_warning_or_error);
3961
3962 if (need_copy_assignment)
3963 {
3964 t = get_copy_assign (type);
3965
3966 if (t && !trivial_fn_p (t))
3967 TREE_VEC_ELT (info, 2) = t;
3968 }
3969
3970 return errorcount != save_errorcount;
3971 }
3972
3973 /* For all elements of CLAUSES, validate them vs OpenMP constraints.
3974 Remove any elements from the list that are invalid. */
3975
3976 tree
finish_omp_clauses(tree clauses)3977 finish_omp_clauses (tree clauses)
3978 {
3979 bitmap_head generic_head, firstprivate_head, lastprivate_head;
3980 tree c, t, *pc = &clauses;
3981 const char *name;
3982
3983 bitmap_obstack_initialize (NULL);
3984 bitmap_initialize (&generic_head, &bitmap_default_obstack);
3985 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack);
3986 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack);
3987
3988 for (pc = &clauses, c = clauses; c ; c = *pc)
3989 {
3990 bool remove = false;
3991
3992 switch (OMP_CLAUSE_CODE (c))
3993 {
3994 case OMP_CLAUSE_SHARED:
3995 name = "shared";
3996 goto check_dup_generic;
3997 case OMP_CLAUSE_PRIVATE:
3998 name = "private";
3999 goto check_dup_generic;
4000 case OMP_CLAUSE_REDUCTION:
4001 name = "reduction";
4002 goto check_dup_generic;
4003 case OMP_CLAUSE_COPYPRIVATE:
4004 name = "copyprivate";
4005 goto check_dup_generic;
4006 case OMP_CLAUSE_COPYIN:
4007 name = "copyin";
4008 goto check_dup_generic;
4009 check_dup_generic:
4010 t = OMP_CLAUSE_DECL (c);
4011 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
4012 {
4013 if (processing_template_decl)
4014 break;
4015 if (DECL_P (t))
4016 error ("%qD is not a variable in clause %qs", t, name);
4017 else
4018 error ("%qE is not a variable in clause %qs", t, name);
4019 remove = true;
4020 }
4021 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
4022 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))
4023 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
4024 {
4025 error ("%qD appears more than once in data clauses", t);
4026 remove = true;
4027 }
4028 else
4029 bitmap_set_bit (&generic_head, DECL_UID (t));
4030 break;
4031
4032 case OMP_CLAUSE_FIRSTPRIVATE:
4033 t = OMP_CLAUSE_DECL (c);
4034 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
4035 {
4036 if (processing_template_decl)
4037 break;
4038 if (DECL_P (t))
4039 error ("%qD is not a variable in clause %<firstprivate%>", t);
4040 else
4041 error ("%qE is not a variable in clause %<firstprivate%>", t);
4042 remove = true;
4043 }
4044 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
4045 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)))
4046 {
4047 error ("%qD appears more than once in data clauses", t);
4048 remove = true;
4049 }
4050 else
4051 bitmap_set_bit (&firstprivate_head, DECL_UID (t));
4052 break;
4053
4054 case OMP_CLAUSE_LASTPRIVATE:
4055 t = OMP_CLAUSE_DECL (c);
4056 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
4057 {
4058 if (processing_template_decl)
4059 break;
4060 if (DECL_P (t))
4061 error ("%qD is not a variable in clause %<lastprivate%>", t);
4062 else
4063 error ("%qE is not a variable in clause %<lastprivate%>", t);
4064 remove = true;
4065 }
4066 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
4067 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
4068 {
4069 error ("%qD appears more than once in data clauses", t);
4070 remove = true;
4071 }
4072 else
4073 bitmap_set_bit (&lastprivate_head, DECL_UID (t));
4074 break;
4075
4076 case OMP_CLAUSE_IF:
4077 t = OMP_CLAUSE_IF_EXPR (c);
4078 t = maybe_convert_cond (t);
4079 if (t == error_mark_node)
4080 remove = true;
4081 else if (!processing_template_decl)
4082 t = fold_build_cleanup_point_expr (TREE_TYPE (t), t);
4083 OMP_CLAUSE_IF_EXPR (c) = t;
4084 break;
4085
4086 case OMP_CLAUSE_FINAL:
4087 t = OMP_CLAUSE_FINAL_EXPR (c);
4088 t = maybe_convert_cond (t);
4089 if (t == error_mark_node)
4090 remove = true;
4091 else if (!processing_template_decl)
4092 t = fold_build_cleanup_point_expr (TREE_TYPE (t), t);
4093 OMP_CLAUSE_FINAL_EXPR (c) = t;
4094 break;
4095
4096 case OMP_CLAUSE_NUM_THREADS:
4097 t = OMP_CLAUSE_NUM_THREADS_EXPR (c);
4098 if (t == error_mark_node)
4099 remove = true;
4100 else if (!type_dependent_expression_p (t)
4101 && !INTEGRAL_TYPE_P (TREE_TYPE (t)))
4102 {
4103 error ("num_threads expression must be integral");
4104 remove = true;
4105 }
4106 else
4107 {
4108 t = mark_rvalue_use (t);
4109 if (!processing_template_decl)
4110 t = fold_build_cleanup_point_expr (TREE_TYPE (t), t);
4111 OMP_CLAUSE_NUM_THREADS_EXPR (c) = t;
4112 }
4113 break;
4114
4115 case OMP_CLAUSE_SCHEDULE:
4116 t = OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (c);
4117 if (t == NULL)
4118 ;
4119 else if (t == error_mark_node)
4120 remove = true;
4121 else if (!type_dependent_expression_p (t)
4122 && !INTEGRAL_TYPE_P (TREE_TYPE (t)))
4123 {
4124 error ("schedule chunk size expression must be integral");
4125 remove = true;
4126 }
4127 else
4128 {
4129 t = mark_rvalue_use (t);
4130 if (!processing_template_decl)
4131 t = fold_build_cleanup_point_expr (TREE_TYPE (t), t);
4132 OMP_CLAUSE_SCHEDULE_CHUNK_EXPR (c) = t;
4133 }
4134 break;
4135
4136 case OMP_CLAUSE_NOWAIT:
4137 case OMP_CLAUSE_ORDERED:
4138 case OMP_CLAUSE_DEFAULT:
4139 case OMP_CLAUSE_UNTIED:
4140 case OMP_CLAUSE_COLLAPSE:
4141 case OMP_CLAUSE_MERGEABLE:
4142 break;
4143
4144 default:
4145 gcc_unreachable ();
4146 }
4147
4148 if (remove)
4149 *pc = OMP_CLAUSE_CHAIN (c);
4150 else
4151 pc = &OMP_CLAUSE_CHAIN (c);
4152 }
4153
4154 for (pc = &clauses, c = clauses; c ; c = *pc)
4155 {
4156 enum omp_clause_code c_kind = OMP_CLAUSE_CODE (c);
4157 bool remove = false;
4158 bool need_complete_non_reference = false;
4159 bool need_default_ctor = false;
4160 bool need_copy_ctor = false;
4161 bool need_copy_assignment = false;
4162 bool need_implicitly_determined = false;
4163 tree type, inner_type;
4164
4165 switch (c_kind)
4166 {
4167 case OMP_CLAUSE_SHARED:
4168 name = "shared";
4169 need_implicitly_determined = true;
4170 break;
4171 case OMP_CLAUSE_PRIVATE:
4172 name = "private";
4173 need_complete_non_reference = true;
4174 need_default_ctor = true;
4175 need_implicitly_determined = true;
4176 break;
4177 case OMP_CLAUSE_FIRSTPRIVATE:
4178 name = "firstprivate";
4179 need_complete_non_reference = true;
4180 need_copy_ctor = true;
4181 need_implicitly_determined = true;
4182 break;
4183 case OMP_CLAUSE_LASTPRIVATE:
4184 name = "lastprivate";
4185 need_complete_non_reference = true;
4186 need_copy_assignment = true;
4187 need_implicitly_determined = true;
4188 break;
4189 case OMP_CLAUSE_REDUCTION:
4190 name = "reduction";
4191 need_implicitly_determined = true;
4192 break;
4193 case OMP_CLAUSE_COPYPRIVATE:
4194 name = "copyprivate";
4195 need_copy_assignment = true;
4196 break;
4197 case OMP_CLAUSE_COPYIN:
4198 name = "copyin";
4199 need_copy_assignment = true;
4200 break;
4201 default:
4202 pc = &OMP_CLAUSE_CHAIN (c);
4203 continue;
4204 }
4205
4206 t = OMP_CLAUSE_DECL (c);
4207 if (processing_template_decl
4208 && TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
4209 {
4210 pc = &OMP_CLAUSE_CHAIN (c);
4211 continue;
4212 }
4213
4214 switch (c_kind)
4215 {
4216 case OMP_CLAUSE_LASTPRIVATE:
4217 if (!bitmap_bit_p (&firstprivate_head, DECL_UID (t)))
4218 need_default_ctor = true;
4219 break;
4220
4221 case OMP_CLAUSE_REDUCTION:
4222 if (AGGREGATE_TYPE_P (TREE_TYPE (t))
4223 || POINTER_TYPE_P (TREE_TYPE (t)))
4224 {
4225 error ("%qE has invalid type for %<reduction%>", t);
4226 remove = true;
4227 }
4228 else if (FLOAT_TYPE_P (TREE_TYPE (t)))
4229 {
4230 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c);
4231 switch (r_code)
4232 {
4233 case PLUS_EXPR:
4234 case MULT_EXPR:
4235 case MINUS_EXPR:
4236 case MIN_EXPR:
4237 case MAX_EXPR:
4238 break;
4239 default:
4240 error ("%qE has invalid type for %<reduction(%s)%>",
4241 t, operator_name_info[r_code].name);
4242 remove = true;
4243 }
4244 }
4245 break;
4246
4247 case OMP_CLAUSE_COPYIN:
4248 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t))
4249 {
4250 error ("%qE must be %<threadprivate%> for %<copyin%>", t);
4251 remove = true;
4252 }
4253 break;
4254
4255 default:
4256 break;
4257 }
4258
4259 if (need_complete_non_reference || need_copy_assignment)
4260 {
4261 t = require_complete_type (t);
4262 if (t == error_mark_node)
4263 remove = true;
4264 else if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE
4265 && need_complete_non_reference)
4266 {
4267 error ("%qE has reference type for %qs", t, name);
4268 remove = true;
4269 }
4270 }
4271 if (need_implicitly_determined)
4272 {
4273 const char *share_name = NULL;
4274
4275 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t))
4276 share_name = "threadprivate";
4277 else switch (cxx_omp_predetermined_sharing (t))
4278 {
4279 case OMP_CLAUSE_DEFAULT_UNSPECIFIED:
4280 break;
4281 case OMP_CLAUSE_DEFAULT_SHARED:
4282 /* const vars may be specified in firstprivate clause. */
4283 if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
4284 && cxx_omp_const_qual_no_mutable (t))
4285 break;
4286 share_name = "shared";
4287 break;
4288 case OMP_CLAUSE_DEFAULT_PRIVATE:
4289 share_name = "private";
4290 break;
4291 default:
4292 gcc_unreachable ();
4293 }
4294 if (share_name)
4295 {
4296 error ("%qE is predetermined %qs for %qs",
4297 t, share_name, name);
4298 remove = true;
4299 }
4300 }
4301
4302 /* We're interested in the base element, not arrays. */
4303 inner_type = type = TREE_TYPE (t);
4304 while (TREE_CODE (inner_type) == ARRAY_TYPE)
4305 inner_type = TREE_TYPE (inner_type);
4306
4307 /* Check for special function availability by building a call to one.
4308 Save the results, because later we won't be in the right context
4309 for making these queries. */
4310 if (CLASS_TYPE_P (inner_type)
4311 && COMPLETE_TYPE_P (inner_type)
4312 && (need_default_ctor || need_copy_ctor || need_copy_assignment)
4313 && !type_dependent_expression_p (t)
4314 && cxx_omp_create_clause_info (c, inner_type, need_default_ctor,
4315 need_copy_ctor, need_copy_assignment))
4316 remove = true;
4317
4318 if (remove)
4319 *pc = OMP_CLAUSE_CHAIN (c);
4320 else
4321 pc = &OMP_CLAUSE_CHAIN (c);
4322 }
4323
4324 bitmap_obstack_release (NULL);
4325 return clauses;
4326 }
4327
4328 /* For all variables in the tree_list VARS, mark them as thread local. */
4329
4330 void
finish_omp_threadprivate(tree vars)4331 finish_omp_threadprivate (tree vars)
4332 {
4333 tree t;
4334
4335 /* Mark every variable in VARS to be assigned thread local storage. */
4336 for (t = vars; t; t = TREE_CHAIN (t))
4337 {
4338 tree v = TREE_PURPOSE (t);
4339
4340 if (error_operand_p (v))
4341 ;
4342 else if (TREE_CODE (v) != VAR_DECL)
4343 error ("%<threadprivate%> %qD is not file, namespace "
4344 "or block scope variable", v);
4345 /* If V had already been marked threadprivate, it doesn't matter
4346 whether it had been used prior to this point. */
4347 else if (TREE_USED (v)
4348 && (DECL_LANG_SPECIFIC (v) == NULL
4349 || !CP_DECL_THREADPRIVATE_P (v)))
4350 error ("%qE declared %<threadprivate%> after first use", v);
4351 else if (! TREE_STATIC (v) && ! DECL_EXTERNAL (v))
4352 error ("automatic variable %qE cannot be %<threadprivate%>", v);
4353 else if (! COMPLETE_TYPE_P (TREE_TYPE (v)))
4354 error ("%<threadprivate%> %qE has incomplete type", v);
4355 else if (TREE_STATIC (v) && TYPE_P (CP_DECL_CONTEXT (v))
4356 && CP_DECL_CONTEXT (v) != current_class_type)
4357 error ("%<threadprivate%> %qE directive not "
4358 "in %qT definition", v, CP_DECL_CONTEXT (v));
4359 else
4360 {
4361 /* Allocate a LANG_SPECIFIC structure for V, if needed. */
4362 if (DECL_LANG_SPECIFIC (v) == NULL)
4363 {
4364 retrofit_lang_decl (v);
4365
4366 /* Make sure that DECL_DISCRIMINATOR_P continues to be true
4367 after the allocation of the lang_decl structure. */
4368 if (DECL_DISCRIMINATOR_P (v))
4369 DECL_LANG_SPECIFIC (v)->u.base.u2sel = 1;
4370 }
4371
4372 if (! DECL_THREAD_LOCAL_P (v))
4373 {
4374 DECL_TLS_MODEL (v) = decl_default_tls_model (v);
4375 /* If rtl has been already set for this var, call
4376 make_decl_rtl once again, so that encode_section_info
4377 has a chance to look at the new decl flags. */
4378 if (DECL_RTL_SET_P (v))
4379 make_decl_rtl (v);
4380 }
4381 CP_DECL_THREADPRIVATE_P (v) = 1;
4382 }
4383 }
4384 }
4385
4386 /* Build an OpenMP structured block. */
4387
4388 tree
begin_omp_structured_block(void)4389 begin_omp_structured_block (void)
4390 {
4391 return do_pushlevel (sk_omp);
4392 }
4393
4394 tree
finish_omp_structured_block(tree block)4395 finish_omp_structured_block (tree block)
4396 {
4397 return do_poplevel (block);
4398 }
4399
4400 /* Similarly, except force the retention of the BLOCK. */
4401
4402 tree
begin_omp_parallel(void)4403 begin_omp_parallel (void)
4404 {
4405 keep_next_level (true);
4406 return begin_omp_structured_block ();
4407 }
4408
4409 tree
finish_omp_parallel(tree clauses,tree body)4410 finish_omp_parallel (tree clauses, tree body)
4411 {
4412 tree stmt;
4413
4414 body = finish_omp_structured_block (body);
4415
4416 stmt = make_node (OMP_PARALLEL);
4417 TREE_TYPE (stmt) = void_type_node;
4418 OMP_PARALLEL_CLAUSES (stmt) = clauses;
4419 OMP_PARALLEL_BODY (stmt) = body;
4420
4421 return add_stmt (stmt);
4422 }
4423
4424 tree
begin_omp_task(void)4425 begin_omp_task (void)
4426 {
4427 keep_next_level (true);
4428 return begin_omp_structured_block ();
4429 }
4430
4431 tree
finish_omp_task(tree clauses,tree body)4432 finish_omp_task (tree clauses, tree body)
4433 {
4434 tree stmt;
4435
4436 body = finish_omp_structured_block (body);
4437
4438 stmt = make_node (OMP_TASK);
4439 TREE_TYPE (stmt) = void_type_node;
4440 OMP_TASK_CLAUSES (stmt) = clauses;
4441 OMP_TASK_BODY (stmt) = body;
4442
4443 return add_stmt (stmt);
4444 }
4445
4446 /* Helper function for finish_omp_for. Convert Ith random access iterator
4447 into integral iterator. Return FALSE if successful. */
4448
4449 static bool
handle_omp_for_class_iterator(int i,location_t locus,tree declv,tree initv,tree condv,tree incrv,tree * body,tree * pre_body,tree clauses)4450 handle_omp_for_class_iterator (int i, location_t locus, tree declv, tree initv,
4451 tree condv, tree incrv, tree *body,
4452 tree *pre_body, tree clauses)
4453 {
4454 tree diff, iter_init, iter_incr = NULL, last;
4455 tree incr_var = NULL, orig_pre_body, orig_body, c;
4456 tree decl = TREE_VEC_ELT (declv, i);
4457 tree init = TREE_VEC_ELT (initv, i);
4458 tree cond = TREE_VEC_ELT (condv, i);
4459 tree incr = TREE_VEC_ELT (incrv, i);
4460 tree iter = decl;
4461 location_t elocus = locus;
4462
4463 if (init && EXPR_HAS_LOCATION (init))
4464 elocus = EXPR_LOCATION (init);
4465
4466 switch (TREE_CODE (cond))
4467 {
4468 case GT_EXPR:
4469 case GE_EXPR:
4470 case LT_EXPR:
4471 case LE_EXPR:
4472 if (TREE_OPERAND (cond, 1) == iter)
4473 cond = build2 (swap_tree_comparison (TREE_CODE (cond)),
4474 TREE_TYPE (cond), iter, TREE_OPERAND (cond, 0));
4475 if (TREE_OPERAND (cond, 0) != iter)
4476 cond = error_mark_node;
4477 else
4478 {
4479 tree tem = build_x_binary_op (TREE_CODE (cond), iter, ERROR_MARK,
4480 TREE_OPERAND (cond, 1), ERROR_MARK,
4481 NULL, tf_warning_or_error);
4482 if (error_operand_p (tem))
4483 return true;
4484 }
4485 break;
4486 default:
4487 cond = error_mark_node;
4488 break;
4489 }
4490 if (cond == error_mark_node)
4491 {
4492 error_at (elocus, "invalid controlling predicate");
4493 return true;
4494 }
4495 diff = build_x_binary_op (MINUS_EXPR, TREE_OPERAND (cond, 1),
4496 ERROR_MARK, iter, ERROR_MARK, NULL,
4497 tf_warning_or_error);
4498 if (error_operand_p (diff))
4499 return true;
4500 if (TREE_CODE (TREE_TYPE (diff)) != INTEGER_TYPE)
4501 {
4502 error_at (elocus, "difference between %qE and %qD does not have integer type",
4503 TREE_OPERAND (cond, 1), iter);
4504 return true;
4505 }
4506
4507 switch (TREE_CODE (incr))
4508 {
4509 case PREINCREMENT_EXPR:
4510 case PREDECREMENT_EXPR:
4511 case POSTINCREMENT_EXPR:
4512 case POSTDECREMENT_EXPR:
4513 if (TREE_OPERAND (incr, 0) != iter)
4514 {
4515 incr = error_mark_node;
4516 break;
4517 }
4518 iter_incr = build_x_unary_op (TREE_CODE (incr), iter,
4519 tf_warning_or_error);
4520 if (error_operand_p (iter_incr))
4521 return true;
4522 else if (TREE_CODE (incr) == PREINCREMENT_EXPR
4523 || TREE_CODE (incr) == POSTINCREMENT_EXPR)
4524 incr = integer_one_node;
4525 else
4526 incr = integer_minus_one_node;
4527 break;
4528 case MODIFY_EXPR:
4529 if (TREE_OPERAND (incr, 0) != iter)
4530 incr = error_mark_node;
4531 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
4532 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
4533 {
4534 tree rhs = TREE_OPERAND (incr, 1);
4535 if (TREE_OPERAND (rhs, 0) == iter)
4536 {
4537 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (rhs, 1)))
4538 != INTEGER_TYPE)
4539 incr = error_mark_node;
4540 else
4541 {
4542 iter_incr = build_x_modify_expr (iter, TREE_CODE (rhs),
4543 TREE_OPERAND (rhs, 1),
4544 tf_warning_or_error);
4545 if (error_operand_p (iter_incr))
4546 return true;
4547 incr = TREE_OPERAND (rhs, 1);
4548 incr = cp_convert (TREE_TYPE (diff), incr);
4549 if (TREE_CODE (rhs) == MINUS_EXPR)
4550 {
4551 incr = build1 (NEGATE_EXPR, TREE_TYPE (diff), incr);
4552 incr = fold_if_not_in_template (incr);
4553 }
4554 if (TREE_CODE (incr) != INTEGER_CST
4555 && (TREE_CODE (incr) != NOP_EXPR
4556 || (TREE_CODE (TREE_OPERAND (incr, 0))
4557 != INTEGER_CST)))
4558 iter_incr = NULL;
4559 }
4560 }
4561 else if (TREE_OPERAND (rhs, 1) == iter)
4562 {
4563 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (rhs, 0))) != INTEGER_TYPE
4564 || TREE_CODE (rhs) != PLUS_EXPR)
4565 incr = error_mark_node;
4566 else
4567 {
4568 iter_incr = build_x_binary_op (PLUS_EXPR,
4569 TREE_OPERAND (rhs, 0),
4570 ERROR_MARK, iter,
4571 ERROR_MARK, NULL,
4572 tf_warning_or_error);
4573 if (error_operand_p (iter_incr))
4574 return true;
4575 iter_incr = build_x_modify_expr (iter, NOP_EXPR,
4576 iter_incr,
4577 tf_warning_or_error);
4578 if (error_operand_p (iter_incr))
4579 return true;
4580 incr = TREE_OPERAND (rhs, 0);
4581 iter_incr = NULL;
4582 }
4583 }
4584 else
4585 incr = error_mark_node;
4586 }
4587 else
4588 incr = error_mark_node;
4589 break;
4590 default:
4591 incr = error_mark_node;
4592 break;
4593 }
4594
4595 if (incr == error_mark_node)
4596 {
4597 error_at (elocus, "invalid increment expression");
4598 return true;
4599 }
4600
4601 incr = cp_convert (TREE_TYPE (diff), incr);
4602 for (c = clauses; c ; c = OMP_CLAUSE_CHAIN (c))
4603 if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE
4604 && OMP_CLAUSE_DECL (c) == iter)
4605 break;
4606
4607 decl = create_temporary_var (TREE_TYPE (diff));
4608 pushdecl (decl);
4609 add_decl_expr (decl);
4610 last = create_temporary_var (TREE_TYPE (diff));
4611 pushdecl (last);
4612 add_decl_expr (last);
4613 if (c && iter_incr == NULL)
4614 {
4615 incr_var = create_temporary_var (TREE_TYPE (diff));
4616 pushdecl (incr_var);
4617 add_decl_expr (incr_var);
4618 }
4619 gcc_assert (stmts_are_full_exprs_p ());
4620
4621 orig_pre_body = *pre_body;
4622 *pre_body = push_stmt_list ();
4623 if (orig_pre_body)
4624 add_stmt (orig_pre_body);
4625 if (init != NULL)
4626 finish_expr_stmt (build_x_modify_expr (iter, NOP_EXPR, init,
4627 tf_warning_or_error));
4628 init = build_int_cst (TREE_TYPE (diff), 0);
4629 if (c && iter_incr == NULL)
4630 {
4631 finish_expr_stmt (build_x_modify_expr (incr_var, NOP_EXPR,
4632 incr, tf_warning_or_error));
4633 incr = incr_var;
4634 iter_incr = build_x_modify_expr (iter, PLUS_EXPR, incr,
4635 tf_warning_or_error);
4636 }
4637 finish_expr_stmt (build_x_modify_expr (last, NOP_EXPR, init,
4638 tf_warning_or_error));
4639 *pre_body = pop_stmt_list (*pre_body);
4640
4641 cond = cp_build_binary_op (elocus,
4642 TREE_CODE (cond), decl, diff,
4643 tf_warning_or_error);
4644 incr = build_modify_expr (elocus, decl, NULL_TREE, PLUS_EXPR,
4645 elocus, incr, NULL_TREE);
4646
4647 orig_body = *body;
4648 *body = push_stmt_list ();
4649 iter_init = build2 (MINUS_EXPR, TREE_TYPE (diff), decl, last);
4650 iter_init = build_x_modify_expr (iter, PLUS_EXPR, iter_init,
4651 tf_warning_or_error);
4652 iter_init = build1 (NOP_EXPR, void_type_node, iter_init);
4653 finish_expr_stmt (iter_init);
4654 finish_expr_stmt (build_x_modify_expr (last, NOP_EXPR, decl,
4655 tf_warning_or_error));
4656 add_stmt (orig_body);
4657 *body = pop_stmt_list (*body);
4658
4659 if (c)
4660 {
4661 OMP_CLAUSE_LASTPRIVATE_STMT (c) = push_stmt_list ();
4662 finish_expr_stmt (iter_incr);
4663 OMP_CLAUSE_LASTPRIVATE_STMT (c)
4664 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (c));
4665 }
4666
4667 TREE_VEC_ELT (declv, i) = decl;
4668 TREE_VEC_ELT (initv, i) = init;
4669 TREE_VEC_ELT (condv, i) = cond;
4670 TREE_VEC_ELT (incrv, i) = incr;
4671
4672 return false;
4673 }
4674
4675 /* Build and validate an OMP_FOR statement. CLAUSES, BODY, COND, INCR
4676 are directly for their associated operands in the statement. DECL
4677 and INIT are a combo; if DECL is NULL then INIT ought to be a
4678 MODIFY_EXPR, and the DECL should be extracted. PRE_BODY are
4679 optional statements that need to go before the loop into its
4680 sk_omp scope. */
4681
4682 tree
finish_omp_for(location_t locus,tree declv,tree initv,tree condv,tree incrv,tree body,tree pre_body,tree clauses)4683 finish_omp_for (location_t locus, tree declv, tree initv, tree condv,
4684 tree incrv, tree body, tree pre_body, tree clauses)
4685 {
4686 tree omp_for = NULL, orig_incr = NULL;
4687 tree decl, init, cond, incr;
4688 location_t elocus;
4689 int i;
4690
4691 gcc_assert (TREE_VEC_LENGTH (declv) == TREE_VEC_LENGTH (initv));
4692 gcc_assert (TREE_VEC_LENGTH (declv) == TREE_VEC_LENGTH (condv));
4693 gcc_assert (TREE_VEC_LENGTH (declv) == TREE_VEC_LENGTH (incrv));
4694 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
4695 {
4696 decl = TREE_VEC_ELT (declv, i);
4697 init = TREE_VEC_ELT (initv, i);
4698 cond = TREE_VEC_ELT (condv, i);
4699 incr = TREE_VEC_ELT (incrv, i);
4700 elocus = locus;
4701
4702 if (decl == NULL)
4703 {
4704 if (init != NULL)
4705 switch (TREE_CODE (init))
4706 {
4707 case MODIFY_EXPR:
4708 decl = TREE_OPERAND (init, 0);
4709 init = TREE_OPERAND (init, 1);
4710 break;
4711 case MODOP_EXPR:
4712 if (TREE_CODE (TREE_OPERAND (init, 1)) == NOP_EXPR)
4713 {
4714 decl = TREE_OPERAND (init, 0);
4715 init = TREE_OPERAND (init, 2);
4716 }
4717 break;
4718 default:
4719 break;
4720 }
4721
4722 if (decl == NULL)
4723 {
4724 error_at (locus,
4725 "expected iteration declaration or initialization");
4726 return NULL;
4727 }
4728 }
4729
4730 if (init && EXPR_HAS_LOCATION (init))
4731 elocus = EXPR_LOCATION (init);
4732
4733 if (cond == NULL)
4734 {
4735 error_at (elocus, "missing controlling predicate");
4736 return NULL;
4737 }
4738
4739 if (incr == NULL)
4740 {
4741 error_at (elocus, "missing increment expression");
4742 return NULL;
4743 }
4744
4745 TREE_VEC_ELT (declv, i) = decl;
4746 TREE_VEC_ELT (initv, i) = init;
4747 }
4748
4749 if (dependent_omp_for_p (declv, initv, condv, incrv))
4750 {
4751 tree stmt;
4752
4753 stmt = make_node (OMP_FOR);
4754
4755 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
4756 {
4757 /* This is really just a place-holder. We'll be decomposing this
4758 again and going through the cp_build_modify_expr path below when
4759 we instantiate the thing. */
4760 TREE_VEC_ELT (initv, i)
4761 = build2 (MODIFY_EXPR, void_type_node, TREE_VEC_ELT (declv, i),
4762 TREE_VEC_ELT (initv, i));
4763 }
4764
4765 TREE_TYPE (stmt) = void_type_node;
4766 OMP_FOR_INIT (stmt) = initv;
4767 OMP_FOR_COND (stmt) = condv;
4768 OMP_FOR_INCR (stmt) = incrv;
4769 OMP_FOR_BODY (stmt) = body;
4770 OMP_FOR_PRE_BODY (stmt) = pre_body;
4771 OMP_FOR_CLAUSES (stmt) = clauses;
4772
4773 SET_EXPR_LOCATION (stmt, locus);
4774 return add_stmt (stmt);
4775 }
4776
4777 if (processing_template_decl)
4778 orig_incr = make_tree_vec (TREE_VEC_LENGTH (incrv));
4779
4780 for (i = 0; i < TREE_VEC_LENGTH (declv); )
4781 {
4782 decl = TREE_VEC_ELT (declv, i);
4783 init = TREE_VEC_ELT (initv, i);
4784 cond = TREE_VEC_ELT (condv, i);
4785 incr = TREE_VEC_ELT (incrv, i);
4786 if (orig_incr)
4787 TREE_VEC_ELT (orig_incr, i) = incr;
4788 elocus = locus;
4789
4790 if (init && EXPR_HAS_LOCATION (init))
4791 elocus = EXPR_LOCATION (init);
4792
4793 if (!DECL_P (decl))
4794 {
4795 error_at (elocus, "expected iteration declaration or initialization");
4796 return NULL;
4797 }
4798
4799 if (incr && TREE_CODE (incr) == MODOP_EXPR)
4800 {
4801 if (orig_incr)
4802 TREE_VEC_ELT (orig_incr, i) = incr;
4803 incr = cp_build_modify_expr (TREE_OPERAND (incr, 0),
4804 TREE_CODE (TREE_OPERAND (incr, 1)),
4805 TREE_OPERAND (incr, 2),
4806 tf_warning_or_error);
4807 }
4808
4809 if (CLASS_TYPE_P (TREE_TYPE (decl)))
4810 {
4811 if (handle_omp_for_class_iterator (i, locus, declv, initv, condv,
4812 incrv, &body, &pre_body, clauses))
4813 return NULL;
4814 continue;
4815 }
4816
4817 if (!INTEGRAL_TYPE_P (TREE_TYPE (decl))
4818 && TREE_CODE (TREE_TYPE (decl)) != POINTER_TYPE)
4819 {
4820 error_at (elocus, "invalid type for iteration variable %qE", decl);
4821 return NULL;
4822 }
4823
4824 if (!processing_template_decl)
4825 {
4826 init = fold_build_cleanup_point_expr (TREE_TYPE (init), init);
4827 init = cp_build_modify_expr (decl, NOP_EXPR, init, tf_warning_or_error);
4828 }
4829 else
4830 init = build2 (MODIFY_EXPR, void_type_node, decl, init);
4831 if (cond
4832 && TREE_SIDE_EFFECTS (cond)
4833 && COMPARISON_CLASS_P (cond)
4834 && !processing_template_decl)
4835 {
4836 tree t = TREE_OPERAND (cond, 0);
4837 if (TREE_SIDE_EFFECTS (t)
4838 && t != decl
4839 && (TREE_CODE (t) != NOP_EXPR
4840 || TREE_OPERAND (t, 0) != decl))
4841 TREE_OPERAND (cond, 0)
4842 = fold_build_cleanup_point_expr (TREE_TYPE (t), t);
4843
4844 t = TREE_OPERAND (cond, 1);
4845 if (TREE_SIDE_EFFECTS (t)
4846 && t != decl
4847 && (TREE_CODE (t) != NOP_EXPR
4848 || TREE_OPERAND (t, 0) != decl))
4849 TREE_OPERAND (cond, 1)
4850 = fold_build_cleanup_point_expr (TREE_TYPE (t), t);
4851 }
4852 if (decl == error_mark_node || init == error_mark_node)
4853 return NULL;
4854
4855 TREE_VEC_ELT (declv, i) = decl;
4856 TREE_VEC_ELT (initv, i) = init;
4857 TREE_VEC_ELT (condv, i) = cond;
4858 TREE_VEC_ELT (incrv, i) = incr;
4859 i++;
4860 }
4861
4862 if (IS_EMPTY_STMT (pre_body))
4863 pre_body = NULL;
4864
4865 omp_for = c_finish_omp_for (locus, declv, initv, condv, incrv,
4866 body, pre_body);
4867
4868 if (omp_for == NULL)
4869 return NULL;
4870
4871 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INCR (omp_for)); i++)
4872 {
4873 decl = TREE_OPERAND (TREE_VEC_ELT (OMP_FOR_INIT (omp_for), i), 0);
4874 incr = TREE_VEC_ELT (OMP_FOR_INCR (omp_for), i);
4875
4876 if (TREE_CODE (incr) != MODIFY_EXPR)
4877 continue;
4878
4879 if (TREE_SIDE_EFFECTS (TREE_OPERAND (incr, 1))
4880 && BINARY_CLASS_P (TREE_OPERAND (incr, 1))
4881 && !processing_template_decl)
4882 {
4883 tree t = TREE_OPERAND (TREE_OPERAND (incr, 1), 0);
4884 if (TREE_SIDE_EFFECTS (t)
4885 && t != decl
4886 && (TREE_CODE (t) != NOP_EXPR
4887 || TREE_OPERAND (t, 0) != decl))
4888 TREE_OPERAND (TREE_OPERAND (incr, 1), 0)
4889 = fold_build_cleanup_point_expr (TREE_TYPE (t), t);
4890
4891 t = TREE_OPERAND (TREE_OPERAND (incr, 1), 1);
4892 if (TREE_SIDE_EFFECTS (t)
4893 && t != decl
4894 && (TREE_CODE (t) != NOP_EXPR
4895 || TREE_OPERAND (t, 0) != decl))
4896 TREE_OPERAND (TREE_OPERAND (incr, 1), 1)
4897 = fold_build_cleanup_point_expr (TREE_TYPE (t), t);
4898 }
4899
4900 if (orig_incr)
4901 TREE_VEC_ELT (OMP_FOR_INCR (omp_for), i) = TREE_VEC_ELT (orig_incr, i);
4902 }
4903 if (omp_for != NULL)
4904 OMP_FOR_CLAUSES (omp_for) = clauses;
4905 return omp_for;
4906 }
4907
4908 void
finish_omp_atomic(enum tree_code code,enum tree_code opcode,tree lhs,tree rhs,tree v,tree lhs1,tree rhs1)4909 finish_omp_atomic (enum tree_code code, enum tree_code opcode, tree lhs,
4910 tree rhs, tree v, tree lhs1, tree rhs1)
4911 {
4912 tree orig_lhs;
4913 tree orig_rhs;
4914 tree orig_v;
4915 tree orig_lhs1;
4916 tree orig_rhs1;
4917 bool dependent_p;
4918 tree stmt;
4919
4920 orig_lhs = lhs;
4921 orig_rhs = rhs;
4922 orig_v = v;
4923 orig_lhs1 = lhs1;
4924 orig_rhs1 = rhs1;
4925 dependent_p = false;
4926 stmt = NULL_TREE;
4927
4928 /* Even in a template, we can detect invalid uses of the atomic
4929 pragma if neither LHS nor RHS is type-dependent. */
4930 if (processing_template_decl)
4931 {
4932 dependent_p = (type_dependent_expression_p (lhs)
4933 || (rhs && type_dependent_expression_p (rhs))
4934 || (v && type_dependent_expression_p (v))
4935 || (lhs1 && type_dependent_expression_p (lhs1))
4936 || (rhs1 && type_dependent_expression_p (rhs1)));
4937 if (!dependent_p)
4938 {
4939 lhs = build_non_dependent_expr (lhs);
4940 if (rhs)
4941 rhs = build_non_dependent_expr (rhs);
4942 if (v)
4943 v = build_non_dependent_expr (v);
4944 if (lhs1)
4945 lhs1 = build_non_dependent_expr (lhs1);
4946 if (rhs1)
4947 rhs1 = build_non_dependent_expr (rhs1);
4948 }
4949 }
4950 if (!dependent_p)
4951 {
4952 stmt = c_finish_omp_atomic (input_location, code, opcode, lhs, rhs,
4953 v, lhs1, rhs1);
4954 if (stmt == error_mark_node)
4955 return;
4956 }
4957 if (processing_template_decl)
4958 {
4959 if (code == OMP_ATOMIC_READ)
4960 {
4961 stmt = build_min_nt (OMP_ATOMIC_READ, orig_lhs);
4962 stmt = build2 (MODIFY_EXPR, void_type_node, orig_v, stmt);
4963 }
4964 else
4965 {
4966 if (opcode == NOP_EXPR)
4967 stmt = build2 (MODIFY_EXPR, void_type_node, orig_lhs, orig_rhs);
4968 else
4969 stmt = build2 (opcode, void_type_node, orig_lhs, orig_rhs);
4970 if (orig_rhs1)
4971 stmt = build_min_nt (COMPOUND_EXPR, orig_rhs1, stmt);
4972 if (code != OMP_ATOMIC)
4973 {
4974 stmt = build_min_nt (code, orig_lhs1, stmt);
4975 stmt = build2 (MODIFY_EXPR, void_type_node, orig_v, stmt);
4976 }
4977 }
4978 stmt = build2 (OMP_ATOMIC, void_type_node, integer_zero_node, stmt);
4979 }
4980 finish_expr_stmt (stmt);
4981 }
4982
4983 void
finish_omp_barrier(void)4984 finish_omp_barrier (void)
4985 {
4986 tree fn = builtin_decl_explicit (BUILT_IN_GOMP_BARRIER);
4987 VEC(tree,gc) *vec = make_tree_vector ();
4988 tree stmt = finish_call_expr (fn, &vec, false, false, tf_warning_or_error);
4989 release_tree_vector (vec);
4990 finish_expr_stmt (stmt);
4991 }
4992
4993 void
finish_omp_flush(void)4994 finish_omp_flush (void)
4995 {
4996 tree fn = builtin_decl_explicit (BUILT_IN_SYNC_SYNCHRONIZE);
4997 VEC(tree,gc) *vec = make_tree_vector ();
4998 tree stmt = finish_call_expr (fn, &vec, false, false, tf_warning_or_error);
4999 release_tree_vector (vec);
5000 finish_expr_stmt (stmt);
5001 }
5002
5003 void
finish_omp_taskwait(void)5004 finish_omp_taskwait (void)
5005 {
5006 tree fn = builtin_decl_explicit (BUILT_IN_GOMP_TASKWAIT);
5007 VEC(tree,gc) *vec = make_tree_vector ();
5008 tree stmt = finish_call_expr (fn, &vec, false, false, tf_warning_or_error);
5009 release_tree_vector (vec);
5010 finish_expr_stmt (stmt);
5011 }
5012
5013 void
finish_omp_taskyield(void)5014 finish_omp_taskyield (void)
5015 {
5016 tree fn = builtin_decl_explicit (BUILT_IN_GOMP_TASKYIELD);
5017 VEC(tree,gc) *vec = make_tree_vector ();
5018 tree stmt = finish_call_expr (fn, &vec, false, false, tf_warning_or_error);
5019 release_tree_vector (vec);
5020 finish_expr_stmt (stmt);
5021 }
5022
5023 /* Begin a __transaction_atomic or __transaction_relaxed statement.
5024 If PCOMPOUND is non-null, this is for a function-transaction-block, and we
5025 should create an extra compound stmt. */
5026
5027 tree
begin_transaction_stmt(location_t loc,tree * pcompound,int flags)5028 begin_transaction_stmt (location_t loc, tree *pcompound, int flags)
5029 {
5030 tree r;
5031
5032 if (pcompound)
5033 *pcompound = begin_compound_stmt (0);
5034
5035 r = build_stmt (loc, TRANSACTION_EXPR, NULL_TREE);
5036
5037 /* Only add the statement to the function if support enabled. */
5038 if (flag_tm)
5039 add_stmt (r);
5040 else
5041 error_at (loc, ((flags & TM_STMT_ATTR_RELAXED) != 0
5042 ? G_("%<__transaction_relaxed%> without "
5043 "transactional memory support enabled")
5044 : G_("%<__transaction_atomic%> without "
5045 "transactional memory support enabled")));
5046
5047 TRANSACTION_EXPR_BODY (r) = push_stmt_list ();
5048 return r;
5049 }
5050
5051 /* End a __transaction_atomic or __transaction_relaxed statement.
5052 If COMPOUND_STMT is non-null, this is for a function-transaction-block,
5053 and we should end the compound. If NOEX is non-NULL, we wrap the body in
5054 a MUST_NOT_THROW_EXPR with NOEX as condition. */
5055
5056 void
finish_transaction_stmt(tree stmt,tree compound_stmt,int flags,tree noex)5057 finish_transaction_stmt (tree stmt, tree compound_stmt, int flags, tree noex)
5058 {
5059 TRANSACTION_EXPR_BODY (stmt) = pop_stmt_list (TRANSACTION_EXPR_BODY (stmt));
5060 TRANSACTION_EXPR_OUTER (stmt) = (flags & TM_STMT_ATTR_OUTER) != 0;
5061 TRANSACTION_EXPR_RELAXED (stmt) = (flags & TM_STMT_ATTR_RELAXED) != 0;
5062 TRANSACTION_EXPR_IS_STMT (stmt) = 1;
5063
5064 /* noexcept specifications are not allowed for function transactions. */
5065 gcc_assert (!(noex && compound_stmt));
5066 if (noex)
5067 {
5068 tree body = build_must_not_throw_expr (TRANSACTION_EXPR_BODY (stmt),
5069 noex);
5070 SET_EXPR_LOCATION (body, EXPR_LOCATION (TRANSACTION_EXPR_BODY (stmt)));
5071 TREE_SIDE_EFFECTS (body) = 1;
5072 TRANSACTION_EXPR_BODY (stmt) = body;
5073 }
5074
5075 if (compound_stmt)
5076 finish_compound_stmt (compound_stmt);
5077 finish_stmt ();
5078 }
5079
5080 /* Build a __transaction_atomic or __transaction_relaxed expression. If
5081 NOEX is non-NULL, we wrap the body in a MUST_NOT_THROW_EXPR with NOEX as
5082 condition. */
5083
5084 tree
build_transaction_expr(location_t loc,tree expr,int flags,tree noex)5085 build_transaction_expr (location_t loc, tree expr, int flags, tree noex)
5086 {
5087 tree ret;
5088 if (noex)
5089 {
5090 expr = build_must_not_throw_expr (expr, noex);
5091 SET_EXPR_LOCATION (expr, loc);
5092 TREE_SIDE_EFFECTS (expr) = 1;
5093 }
5094 ret = build1 (TRANSACTION_EXPR, TREE_TYPE (expr), expr);
5095 if (flags & TM_STMT_ATTR_RELAXED)
5096 TRANSACTION_EXPR_RELAXED (ret) = 1;
5097 SET_EXPR_LOCATION (ret, loc);
5098 return ret;
5099 }
5100
5101 void
init_cp_semantics(void)5102 init_cp_semantics (void)
5103 {
5104 }
5105
5106 /* Build a STATIC_ASSERT for a static assertion with the condition
5107 CONDITION and the message text MESSAGE. LOCATION is the location
5108 of the static assertion in the source code. When MEMBER_P, this
5109 static assertion is a member of a class. */
5110 void
finish_static_assert(tree condition,tree message,location_t location,bool member_p)5111 finish_static_assert (tree condition, tree message, location_t location,
5112 bool member_p)
5113 {
5114 if (check_for_bare_parameter_packs (condition))
5115 condition = error_mark_node;
5116
5117 if (type_dependent_expression_p (condition)
5118 || value_dependent_expression_p (condition))
5119 {
5120 /* We're in a template; build a STATIC_ASSERT and put it in
5121 the right place. */
5122 tree assertion;
5123
5124 assertion = make_node (STATIC_ASSERT);
5125 STATIC_ASSERT_CONDITION (assertion) = condition;
5126 STATIC_ASSERT_MESSAGE (assertion) = message;
5127 STATIC_ASSERT_SOURCE_LOCATION (assertion) = location;
5128
5129 if (member_p)
5130 maybe_add_class_template_decl_list (current_class_type,
5131 assertion,
5132 /*friend_p=*/0);
5133 else
5134 add_stmt (assertion);
5135
5136 return;
5137 }
5138
5139 /* Fold the expression and convert it to a boolean value. */
5140 condition = fold_non_dependent_expr (condition);
5141 condition = cp_convert (boolean_type_node, condition);
5142 condition = maybe_constant_value (condition);
5143
5144 if (TREE_CODE (condition) == INTEGER_CST && !integer_zerop (condition))
5145 /* Do nothing; the condition is satisfied. */
5146 ;
5147 else
5148 {
5149 location_t saved_loc = input_location;
5150
5151 input_location = location;
5152 if (TREE_CODE (condition) == INTEGER_CST
5153 && integer_zerop (condition))
5154 /* Report the error. */
5155 error ("static assertion failed: %s", TREE_STRING_POINTER (message));
5156 else if (condition && condition != error_mark_node)
5157 {
5158 error ("non-constant condition for static assertion");
5159 cxx_constant_value (condition);
5160 }
5161 input_location = saved_loc;
5162 }
5163 }
5164
5165 /* Implements the C++0x decltype keyword. Returns the type of EXPR,
5166 suitable for use as a type-specifier.
5167
5168 ID_EXPRESSION_OR_MEMBER_ACCESS_P is true when EXPR was parsed as an
5169 id-expression or a class member access, FALSE when it was parsed as
5170 a full expression. */
5171
5172 tree
finish_decltype_type(tree expr,bool id_expression_or_member_access_p,tsubst_flags_t complain)5173 finish_decltype_type (tree expr, bool id_expression_or_member_access_p,
5174 tsubst_flags_t complain)
5175 {
5176 tree type = NULL_TREE;
5177
5178 if (!expr || error_operand_p (expr))
5179 return error_mark_node;
5180
5181 if (TYPE_P (expr)
5182 || TREE_CODE (expr) == TYPE_DECL
5183 || (TREE_CODE (expr) == BIT_NOT_EXPR
5184 && TYPE_P (TREE_OPERAND (expr, 0))))
5185 {
5186 if (complain & tf_error)
5187 error ("argument to decltype must be an expression");
5188 return error_mark_node;
5189 }
5190
5191 /* FIXME instantiation-dependent */
5192 if (type_dependent_expression_p (expr)
5193 /* In a template, a COMPONENT_REF has an IDENTIFIER_NODE for op1 even
5194 if it isn't dependent, so that we can check access control at
5195 instantiation time, so defer the decltype as well (PR 42277). */
5196 || (id_expression_or_member_access_p
5197 && processing_template_decl
5198 && TREE_CODE (expr) == COMPONENT_REF))
5199 {
5200 type = cxx_make_type (DECLTYPE_TYPE);
5201 DECLTYPE_TYPE_EXPR (type) = expr;
5202 DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (type)
5203 = id_expression_or_member_access_p;
5204 SET_TYPE_STRUCTURAL_EQUALITY (type);
5205
5206 return type;
5207 }
5208
5209 /* The type denoted by decltype(e) is defined as follows: */
5210
5211 expr = resolve_nondeduced_context (expr);
5212
5213 if (type_unknown_p (expr))
5214 {
5215 if (complain & tf_error)
5216 error ("decltype cannot resolve address of overloaded function");
5217 return error_mark_node;
5218 }
5219
5220 if (invalid_nonstatic_memfn_p (expr, complain))
5221 return error_mark_node;
5222
5223 /* To get the size of a static data member declared as an array of
5224 unknown bound, we need to instantiate it. */
5225 if (TREE_CODE (expr) == VAR_DECL
5226 && VAR_HAD_UNKNOWN_BOUND (expr)
5227 && DECL_TEMPLATE_INSTANTIATION (expr))
5228 instantiate_decl (expr, /*defer_ok*/true, /*expl_inst_mem*/false);
5229
5230 if (id_expression_or_member_access_p)
5231 {
5232 /* If e is an id-expression or a class member access (5.2.5
5233 [expr.ref]), decltype(e) is defined as the type of the entity
5234 named by e. If there is no such entity, or e names a set of
5235 overloaded functions, the program is ill-formed. */
5236 if (TREE_CODE (expr) == IDENTIFIER_NODE)
5237 expr = lookup_name (expr);
5238
5239 if (TREE_CODE (expr) == INDIRECT_REF)
5240 /* This can happen when the expression is, e.g., "a.b". Just
5241 look at the underlying operand. */
5242 expr = TREE_OPERAND (expr, 0);
5243
5244 if (TREE_CODE (expr) == OFFSET_REF
5245 || TREE_CODE (expr) == MEMBER_REF)
5246 /* We're only interested in the field itself. If it is a
5247 BASELINK, we will need to see through it in the next
5248 step. */
5249 expr = TREE_OPERAND (expr, 1);
5250
5251 if (BASELINK_P (expr))
5252 /* See through BASELINK nodes to the underlying function. */
5253 expr = BASELINK_FUNCTIONS (expr);
5254
5255 switch (TREE_CODE (expr))
5256 {
5257 case FIELD_DECL:
5258 if (DECL_BIT_FIELD_TYPE (expr))
5259 {
5260 type = DECL_BIT_FIELD_TYPE (expr);
5261 break;
5262 }
5263 /* Fall through for fields that aren't bitfields. */
5264
5265 case FUNCTION_DECL:
5266 case VAR_DECL:
5267 case CONST_DECL:
5268 case PARM_DECL:
5269 case RESULT_DECL:
5270 case TEMPLATE_PARM_INDEX:
5271 expr = mark_type_use (expr);
5272 type = TREE_TYPE (expr);
5273 break;
5274
5275 case ERROR_MARK:
5276 type = error_mark_node;
5277 break;
5278
5279 case COMPONENT_REF:
5280 mark_type_use (expr);
5281 type = is_bitfield_expr_with_lowered_type (expr);
5282 if (!type)
5283 type = TREE_TYPE (TREE_OPERAND (expr, 1));
5284 break;
5285
5286 case BIT_FIELD_REF:
5287 gcc_unreachable ();
5288
5289 case INTEGER_CST:
5290 case PTRMEM_CST:
5291 /* We can get here when the id-expression refers to an
5292 enumerator or non-type template parameter. */
5293 type = TREE_TYPE (expr);
5294 break;
5295
5296 default:
5297 gcc_unreachable ();
5298 return error_mark_node;
5299 }
5300 }
5301 else
5302 {
5303 /* Within a lambda-expression:
5304
5305 Every occurrence of decltype((x)) where x is a possibly
5306 parenthesized id-expression that names an entity of
5307 automatic storage duration is treated as if x were
5308 transformed into an access to a corresponding data member
5309 of the closure type that would have been declared if x
5310 were a use of the denoted entity. */
5311 if (outer_automatic_var_p (expr)
5312 && current_function_decl
5313 && LAMBDA_FUNCTION_P (current_function_decl))
5314 type = capture_decltype (expr);
5315 else if (error_operand_p (expr))
5316 type = error_mark_node;
5317 else if (expr == current_class_ptr)
5318 /* If the expression is just "this", we want the
5319 cv-unqualified pointer for the "this" type. */
5320 type = TYPE_MAIN_VARIANT (TREE_TYPE (expr));
5321 else
5322 {
5323 /* Otherwise, where T is the type of e, if e is an lvalue,
5324 decltype(e) is defined as T&; if an xvalue, T&&; otherwise, T. */
5325 cp_lvalue_kind clk = lvalue_kind (expr);
5326 type = unlowered_expr_type (expr);
5327 gcc_assert (TREE_CODE (type) != REFERENCE_TYPE);
5328 if (clk != clk_none && !(clk & clk_class))
5329 type = cp_build_reference_type (type, (clk & clk_rvalueref));
5330 }
5331 }
5332
5333 return type;
5334 }
5335
5336 /* Called from trait_expr_value to evaluate either __has_nothrow_assign or
5337 __has_nothrow_copy, depending on assign_p. */
5338
5339 static bool
classtype_has_nothrow_assign_or_copy_p(tree type,bool assign_p)5340 classtype_has_nothrow_assign_or_copy_p (tree type, bool assign_p)
5341 {
5342 tree fns;
5343
5344 if (assign_p)
5345 {
5346 int ix;
5347 ix = lookup_fnfields_1 (type, ansi_assopname (NOP_EXPR));
5348 if (ix < 0)
5349 return false;
5350 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (type), ix);
5351 }
5352 else if (TYPE_HAS_COPY_CTOR (type))
5353 {
5354 /* If construction of the copy constructor was postponed, create
5355 it now. */
5356 if (CLASSTYPE_LAZY_COPY_CTOR (type))
5357 lazily_declare_fn (sfk_copy_constructor, type);
5358 if (CLASSTYPE_LAZY_MOVE_CTOR (type))
5359 lazily_declare_fn (sfk_move_constructor, type);
5360 fns = CLASSTYPE_CONSTRUCTORS (type);
5361 }
5362 else
5363 return false;
5364
5365 for (; fns; fns = OVL_NEXT (fns))
5366 {
5367 tree fn = OVL_CURRENT (fns);
5368
5369 if (assign_p)
5370 {
5371 if (copy_fn_p (fn) == 0)
5372 continue;
5373 }
5374 else if (copy_fn_p (fn) <= 0)
5375 continue;
5376
5377 maybe_instantiate_noexcept (fn);
5378 if (!TYPE_NOTHROW_P (TREE_TYPE (fn)))
5379 return false;
5380 }
5381
5382 return true;
5383 }
5384
5385 /* Actually evaluates the trait. */
5386
5387 static bool
trait_expr_value(cp_trait_kind kind,tree type1,tree type2)5388 trait_expr_value (cp_trait_kind kind, tree type1, tree type2)
5389 {
5390 enum tree_code type_code1;
5391 tree t;
5392
5393 type_code1 = TREE_CODE (type1);
5394
5395 switch (kind)
5396 {
5397 case CPTK_HAS_NOTHROW_ASSIGN:
5398 type1 = strip_array_types (type1);
5399 return (!CP_TYPE_CONST_P (type1) && type_code1 != REFERENCE_TYPE
5400 && (trait_expr_value (CPTK_HAS_TRIVIAL_ASSIGN, type1, type2)
5401 || (CLASS_TYPE_P (type1)
5402 && classtype_has_nothrow_assign_or_copy_p (type1,
5403 true))));
5404
5405 case CPTK_HAS_TRIVIAL_ASSIGN:
5406 /* ??? The standard seems to be missing the "or array of such a class
5407 type" wording for this trait. */
5408 type1 = strip_array_types (type1);
5409 return (!CP_TYPE_CONST_P (type1) && type_code1 != REFERENCE_TYPE
5410 && (trivial_type_p (type1)
5411 || (CLASS_TYPE_P (type1)
5412 && TYPE_HAS_TRIVIAL_COPY_ASSIGN (type1))));
5413
5414 case CPTK_HAS_NOTHROW_CONSTRUCTOR:
5415 type1 = strip_array_types (type1);
5416 return (trait_expr_value (CPTK_HAS_TRIVIAL_CONSTRUCTOR, type1, type2)
5417 || (CLASS_TYPE_P (type1)
5418 && (t = locate_ctor (type1))
5419 && (maybe_instantiate_noexcept (t),
5420 TYPE_NOTHROW_P (TREE_TYPE (t)))));
5421
5422 case CPTK_HAS_TRIVIAL_CONSTRUCTOR:
5423 type1 = strip_array_types (type1);
5424 return (trivial_type_p (type1)
5425 || (CLASS_TYPE_P (type1) && TYPE_HAS_TRIVIAL_DFLT (type1)));
5426
5427 case CPTK_HAS_NOTHROW_COPY:
5428 type1 = strip_array_types (type1);
5429 return (trait_expr_value (CPTK_HAS_TRIVIAL_COPY, type1, type2)
5430 || (CLASS_TYPE_P (type1)
5431 && classtype_has_nothrow_assign_or_copy_p (type1, false)));
5432
5433 case CPTK_HAS_TRIVIAL_COPY:
5434 /* ??? The standard seems to be missing the "or array of such a class
5435 type" wording for this trait. */
5436 type1 = strip_array_types (type1);
5437 return (trivial_type_p (type1) || type_code1 == REFERENCE_TYPE
5438 || (CLASS_TYPE_P (type1) && TYPE_HAS_TRIVIAL_COPY_CTOR (type1)));
5439
5440 case CPTK_HAS_TRIVIAL_DESTRUCTOR:
5441 type1 = strip_array_types (type1);
5442 return (trivial_type_p (type1) || type_code1 == REFERENCE_TYPE
5443 || (CLASS_TYPE_P (type1)
5444 && TYPE_HAS_TRIVIAL_DESTRUCTOR (type1)));
5445
5446 case CPTK_HAS_VIRTUAL_DESTRUCTOR:
5447 return type_has_virtual_destructor (type1);
5448
5449 case CPTK_IS_ABSTRACT:
5450 return (CLASS_TYPE_P (type1) && CLASSTYPE_PURE_VIRTUALS (type1));
5451
5452 case CPTK_IS_BASE_OF:
5453 return (NON_UNION_CLASS_TYPE_P (type1) && NON_UNION_CLASS_TYPE_P (type2)
5454 && DERIVED_FROM_P (type1, type2));
5455
5456 case CPTK_IS_CLASS:
5457 return (NON_UNION_CLASS_TYPE_P (type1));
5458
5459 case CPTK_IS_CONVERTIBLE_TO:
5460 /* TODO */
5461 return false;
5462
5463 case CPTK_IS_EMPTY:
5464 return (NON_UNION_CLASS_TYPE_P (type1) && CLASSTYPE_EMPTY_P (type1));
5465
5466 case CPTK_IS_ENUM:
5467 return (type_code1 == ENUMERAL_TYPE);
5468
5469 case CPTK_IS_FINAL:
5470 return (CLASS_TYPE_P (type1) && CLASSTYPE_FINAL (type1));
5471
5472 case CPTK_IS_LITERAL_TYPE:
5473 return (literal_type_p (type1));
5474
5475 case CPTK_IS_POD:
5476 return (pod_type_p (type1));
5477
5478 case CPTK_IS_POLYMORPHIC:
5479 return (CLASS_TYPE_P (type1) && TYPE_POLYMORPHIC_P (type1));
5480
5481 case CPTK_IS_STD_LAYOUT:
5482 return (std_layout_type_p (type1));
5483
5484 case CPTK_IS_TRIVIAL:
5485 return (trivial_type_p (type1));
5486
5487 case CPTK_IS_UNION:
5488 return (type_code1 == UNION_TYPE);
5489
5490 default:
5491 gcc_unreachable ();
5492 return false;
5493 }
5494 }
5495
5496 /* If TYPE is an array of unknown bound, or (possibly cv-qualified)
5497 void, or a complete type, returns it, otherwise NULL_TREE. */
5498
5499 static tree
check_trait_type(tree type)5500 check_trait_type (tree type)
5501 {
5502 if (TREE_CODE (type) == ARRAY_TYPE && !TYPE_DOMAIN (type)
5503 && COMPLETE_TYPE_P (TREE_TYPE (type)))
5504 return type;
5505
5506 if (VOID_TYPE_P (type))
5507 return type;
5508
5509 return complete_type_or_else (strip_array_types (type), NULL_TREE);
5510 }
5511
5512 /* Process a trait expression. */
5513
5514 tree
finish_trait_expr(cp_trait_kind kind,tree type1,tree type2)5515 finish_trait_expr (cp_trait_kind kind, tree type1, tree type2)
5516 {
5517 gcc_assert (kind == CPTK_HAS_NOTHROW_ASSIGN
5518 || kind == CPTK_HAS_NOTHROW_CONSTRUCTOR
5519 || kind == CPTK_HAS_NOTHROW_COPY
5520 || kind == CPTK_HAS_TRIVIAL_ASSIGN
5521 || kind == CPTK_HAS_TRIVIAL_CONSTRUCTOR
5522 || kind == CPTK_HAS_TRIVIAL_COPY
5523 || kind == CPTK_HAS_TRIVIAL_DESTRUCTOR
5524 || kind == CPTK_HAS_VIRTUAL_DESTRUCTOR
5525 || kind == CPTK_IS_ABSTRACT
5526 || kind == CPTK_IS_BASE_OF
5527 || kind == CPTK_IS_CLASS
5528 || kind == CPTK_IS_CONVERTIBLE_TO
5529 || kind == CPTK_IS_EMPTY
5530 || kind == CPTK_IS_ENUM
5531 || kind == CPTK_IS_FINAL
5532 || kind == CPTK_IS_LITERAL_TYPE
5533 || kind == CPTK_IS_POD
5534 || kind == CPTK_IS_POLYMORPHIC
5535 || kind == CPTK_IS_STD_LAYOUT
5536 || kind == CPTK_IS_TRIVIAL
5537 || kind == CPTK_IS_UNION);
5538
5539 if (kind == CPTK_IS_CONVERTIBLE_TO)
5540 {
5541 sorry ("__is_convertible_to");
5542 return error_mark_node;
5543 }
5544
5545 if (type1 == error_mark_node
5546 || ((kind == CPTK_IS_BASE_OF || kind == CPTK_IS_CONVERTIBLE_TO)
5547 && type2 == error_mark_node))
5548 return error_mark_node;
5549
5550 if (processing_template_decl)
5551 {
5552 tree trait_expr = make_node (TRAIT_EXPR);
5553 TREE_TYPE (trait_expr) = boolean_type_node;
5554 TRAIT_EXPR_TYPE1 (trait_expr) = type1;
5555 TRAIT_EXPR_TYPE2 (trait_expr) = type2;
5556 TRAIT_EXPR_KIND (trait_expr) = kind;
5557 return trait_expr;
5558 }
5559
5560 switch (kind)
5561 {
5562 case CPTK_HAS_NOTHROW_ASSIGN:
5563 case CPTK_HAS_TRIVIAL_ASSIGN:
5564 case CPTK_HAS_NOTHROW_CONSTRUCTOR:
5565 case CPTK_HAS_TRIVIAL_CONSTRUCTOR:
5566 case CPTK_HAS_NOTHROW_COPY:
5567 case CPTK_HAS_TRIVIAL_COPY:
5568 case CPTK_HAS_TRIVIAL_DESTRUCTOR:
5569 case CPTK_HAS_VIRTUAL_DESTRUCTOR:
5570 case CPTK_IS_ABSTRACT:
5571 case CPTK_IS_EMPTY:
5572 case CPTK_IS_FINAL:
5573 case CPTK_IS_LITERAL_TYPE:
5574 case CPTK_IS_POD:
5575 case CPTK_IS_POLYMORPHIC:
5576 case CPTK_IS_STD_LAYOUT:
5577 case CPTK_IS_TRIVIAL:
5578 if (!check_trait_type (type1))
5579 return error_mark_node;
5580 break;
5581
5582 case CPTK_IS_BASE_OF:
5583 if (NON_UNION_CLASS_TYPE_P (type1) && NON_UNION_CLASS_TYPE_P (type2)
5584 && !same_type_ignoring_top_level_qualifiers_p (type1, type2)
5585 && !complete_type_or_else (type2, NULL_TREE))
5586 /* We already issued an error. */
5587 return error_mark_node;
5588 break;
5589
5590 case CPTK_IS_CLASS:
5591 case CPTK_IS_ENUM:
5592 case CPTK_IS_UNION:
5593 break;
5594
5595 case CPTK_IS_CONVERTIBLE_TO:
5596 default:
5597 gcc_unreachable ();
5598 }
5599
5600 return (trait_expr_value (kind, type1, type2)
5601 ? boolean_true_node : boolean_false_node);
5602 }
5603
5604 /* Do-nothing variants of functions to handle pragma FLOAT_CONST_DECIMAL64,
5605 which is ignored for C++. */
5606
5607 void
set_float_const_decimal64(void)5608 set_float_const_decimal64 (void)
5609 {
5610 }
5611
5612 void
clear_float_const_decimal64(void)5613 clear_float_const_decimal64 (void)
5614 {
5615 }
5616
5617 bool
float_const_decimal64_p(void)5618 float_const_decimal64_p (void)
5619 {
5620 return 0;
5621 }
5622
5623
5624 /* Return true if T is a literal type. */
5625
5626 bool
literal_type_p(tree t)5627 literal_type_p (tree t)
5628 {
5629 if (SCALAR_TYPE_P (t)
5630 || TREE_CODE (t) == REFERENCE_TYPE)
5631 return true;
5632 if (CLASS_TYPE_P (t))
5633 {
5634 t = complete_type (t);
5635 gcc_assert (COMPLETE_TYPE_P (t) || errorcount);
5636 return CLASSTYPE_LITERAL_P (t);
5637 }
5638 if (TREE_CODE (t) == ARRAY_TYPE)
5639 return literal_type_p (strip_array_types (t));
5640 return false;
5641 }
5642
5643 /* If DECL is a variable declared `constexpr', require its type
5644 be literal. Return the DECL if OK, otherwise NULL. */
5645
5646 tree
ensure_literal_type_for_constexpr_object(tree decl)5647 ensure_literal_type_for_constexpr_object (tree decl)
5648 {
5649 tree type = TREE_TYPE (decl);
5650 if (TREE_CODE (decl) == VAR_DECL && DECL_DECLARED_CONSTEXPR_P (decl)
5651 && !processing_template_decl)
5652 {
5653 if (CLASS_TYPE_P (type) && !COMPLETE_TYPE_P (complete_type (type)))
5654 /* Don't complain here, we'll complain about incompleteness
5655 when we try to initialize the variable. */;
5656 else if (!literal_type_p (type))
5657 {
5658 error ("the type %qT of constexpr variable %qD is not literal",
5659 type, decl);
5660 explain_non_literal_class (type);
5661 return NULL;
5662 }
5663 }
5664 return decl;
5665 }
5666
5667 /* Representation of entries in the constexpr function definition table. */
5668
5669 typedef struct GTY(()) constexpr_fundef {
5670 tree decl;
5671 tree body;
5672 } constexpr_fundef;
5673
5674 /* This table holds all constexpr function definitions seen in
5675 the current translation unit. */
5676
5677 static GTY ((param_is (constexpr_fundef))) htab_t constexpr_fundef_table;
5678
5679 /* Utility function used for managing the constexpr function table.
5680 Return true if the entries pointed to by P and Q are for the
5681 same constexpr function. */
5682
5683 static inline int
constexpr_fundef_equal(const void * p,const void * q)5684 constexpr_fundef_equal (const void *p, const void *q)
5685 {
5686 const constexpr_fundef *lhs = (const constexpr_fundef *) p;
5687 const constexpr_fundef *rhs = (const constexpr_fundef *) q;
5688 return lhs->decl == rhs->decl;
5689 }
5690
5691 /* Utility function used for managing the constexpr function table.
5692 Return a hash value for the entry pointed to by Q. */
5693
5694 static inline hashval_t
constexpr_fundef_hash(const void * p)5695 constexpr_fundef_hash (const void *p)
5696 {
5697 const constexpr_fundef *fundef = (const constexpr_fundef *) p;
5698 return DECL_UID (fundef->decl);
5699 }
5700
5701 /* Return a previously saved definition of function FUN. */
5702
5703 static constexpr_fundef *
retrieve_constexpr_fundef(tree fun)5704 retrieve_constexpr_fundef (tree fun)
5705 {
5706 constexpr_fundef fundef = { NULL, NULL };
5707 if (constexpr_fundef_table == NULL)
5708 return NULL;
5709
5710 fundef.decl = fun;
5711 return (constexpr_fundef *) htab_find (constexpr_fundef_table, &fundef);
5712 }
5713
5714 /* Check whether the parameter and return types of FUN are valid for a
5715 constexpr function, and complain if COMPLAIN. */
5716
5717 static bool
is_valid_constexpr_fn(tree fun,bool complain)5718 is_valid_constexpr_fn (tree fun, bool complain)
5719 {
5720 tree parm = FUNCTION_FIRST_USER_PARM (fun);
5721 bool ret = true;
5722 for (; parm != NULL; parm = TREE_CHAIN (parm))
5723 if (!literal_type_p (TREE_TYPE (parm)))
5724 {
5725 ret = false;
5726 if (complain)
5727 {
5728 error ("invalid type for parameter %d of constexpr "
5729 "function %q+#D", DECL_PARM_INDEX (parm), fun);
5730 explain_non_literal_class (TREE_TYPE (parm));
5731 }
5732 }
5733
5734 if (!DECL_CONSTRUCTOR_P (fun))
5735 {
5736 tree rettype = TREE_TYPE (TREE_TYPE (fun));
5737 if (!literal_type_p (rettype))
5738 {
5739 ret = false;
5740 if (complain)
5741 {
5742 error ("invalid return type %qT of constexpr function %q+D",
5743 rettype, fun);
5744 explain_non_literal_class (rettype);
5745 }
5746 }
5747
5748 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fun)
5749 && !CLASSTYPE_LITERAL_P (DECL_CONTEXT (fun)))
5750 {
5751 ret = false;
5752 if (complain)
5753 {
5754 error ("enclosing class of constexpr non-static member "
5755 "function %q+#D is not a literal type", fun);
5756 explain_non_literal_class (DECL_CONTEXT (fun));
5757 }
5758 }
5759 }
5760 else if (CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fun)))
5761 {
5762 ret = false;
5763 if (complain)
5764 error ("%q#T has virtual base classes", DECL_CONTEXT (fun));
5765 }
5766
5767 return ret;
5768 }
5769
5770 /* Subroutine of build_constexpr_constructor_member_initializers.
5771 The expression tree T represents a data member initialization
5772 in a (constexpr) constructor definition. Build a pairing of
5773 the data member with its initializer, and prepend that pair
5774 to the existing initialization pair INITS. */
5775
5776 static bool
build_data_member_initialization(tree t,VEC (constructor_elt,gc)** vec)5777 build_data_member_initialization (tree t, VEC(constructor_elt,gc) **vec)
5778 {
5779 tree member, init;
5780 if (TREE_CODE (t) == CLEANUP_POINT_EXPR)
5781 t = TREE_OPERAND (t, 0);
5782 if (TREE_CODE (t) == EXPR_STMT)
5783 t = TREE_OPERAND (t, 0);
5784 if (t == error_mark_node)
5785 return false;
5786 if (TREE_CODE (t) == STATEMENT_LIST)
5787 {
5788 tree_stmt_iterator i;
5789 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
5790 {
5791 if (! build_data_member_initialization (tsi_stmt (i), vec))
5792 return false;
5793 }
5794 return true;
5795 }
5796 if (TREE_CODE (t) == CLEANUP_STMT)
5797 {
5798 /* We can't see a CLEANUP_STMT in a constructor for a literal class,
5799 but we can in a constexpr constructor for a non-literal class. Just
5800 ignore it; either all the initialization will be constant, in which
5801 case the cleanup can't run, or it can't be constexpr.
5802 Still recurse into CLEANUP_BODY. */
5803 return build_data_member_initialization (CLEANUP_BODY (t), vec);
5804 }
5805 if (TREE_CODE (t) == CONVERT_EXPR)
5806 t = TREE_OPERAND (t, 0);
5807 if (TREE_CODE (t) == INIT_EXPR
5808 || TREE_CODE (t) == MODIFY_EXPR)
5809 {
5810 member = TREE_OPERAND (t, 0);
5811 init = unshare_expr (TREE_OPERAND (t, 1));
5812 }
5813 else if (TREE_CODE (t) == CALL_EXPR)
5814 {
5815 member = CALL_EXPR_ARG (t, 0);
5816 /* We don't use build_cplus_new here because it complains about
5817 abstract bases. Leaving the call unwrapped means that it has the
5818 wrong type, but cxx_eval_constant_expression doesn't care. */
5819 init = unshare_expr (t);
5820 }
5821 else if (TREE_CODE (t) == DECL_EXPR)
5822 /* Declaring a temporary, don't add it to the CONSTRUCTOR. */
5823 return true;
5824 else
5825 gcc_unreachable ();
5826 if (TREE_CODE (member) == INDIRECT_REF)
5827 member = TREE_OPERAND (member, 0);
5828 if (TREE_CODE (member) == NOP_EXPR)
5829 {
5830 tree op = member;
5831 STRIP_NOPS (op);
5832 if (TREE_CODE (op) == ADDR_EXPR)
5833 {
5834 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5835 (TREE_TYPE (TREE_TYPE (op)),
5836 TREE_TYPE (TREE_TYPE (member))));
5837 /* Initializing a cv-qualified member; we need to look through
5838 the const_cast. */
5839 member = op;
5840 }
5841 else if (op == current_class_ptr
5842 && (same_type_ignoring_top_level_qualifiers_p
5843 (TREE_TYPE (TREE_TYPE (member)),
5844 current_class_type)))
5845 /* Delegating constructor. */
5846 member = op;
5847 else
5848 {
5849 /* This is an initializer for an empty base; keep it for now so
5850 we can check it in cxx_eval_bare_aggregate. */
5851 gcc_assert (is_empty_class (TREE_TYPE (TREE_TYPE (member))));
5852 }
5853 }
5854 if (TREE_CODE (member) == ADDR_EXPR)
5855 member = TREE_OPERAND (member, 0);
5856 if (TREE_CODE (member) == COMPONENT_REF
5857 /* If we're initializing a member of a subaggregate, it's a vtable
5858 pointer. Leave it as COMPONENT_REF so we remember the path to get
5859 to the vfield. */
5860 && TREE_CODE (TREE_OPERAND (member, 0)) != COMPONENT_REF)
5861 member = TREE_OPERAND (member, 1);
5862 CONSTRUCTOR_APPEND_ELT (*vec, member, init);
5863 return true;
5864 }
5865
5866 /* Make sure that there are no statements after LAST in the constructor
5867 body represented by LIST. */
5868
5869 bool
check_constexpr_ctor_body(tree last,tree list)5870 check_constexpr_ctor_body (tree last, tree list)
5871 {
5872 bool ok = true;
5873 if (TREE_CODE (list) == STATEMENT_LIST)
5874 {
5875 tree_stmt_iterator i = tsi_last (list);
5876 for (; !tsi_end_p (i); tsi_prev (&i))
5877 {
5878 tree t = tsi_stmt (i);
5879 if (t == last)
5880 break;
5881 if (TREE_CODE (t) == BIND_EXPR)
5882 {
5883 if (!check_constexpr_ctor_body (last, BIND_EXPR_BODY (t)))
5884 return false;
5885 else
5886 continue;
5887 }
5888 /* We currently allow typedefs and static_assert.
5889 FIXME allow them in the standard, too. */
5890 if (TREE_CODE (t) != STATIC_ASSERT)
5891 {
5892 ok = false;
5893 break;
5894 }
5895 }
5896 }
5897 else if (list != last
5898 && TREE_CODE (list) != STATIC_ASSERT)
5899 ok = false;
5900 if (!ok)
5901 {
5902 error ("constexpr constructor does not have empty body");
5903 DECL_DECLARED_CONSTEXPR_P (current_function_decl) = false;
5904 }
5905 return ok;
5906 }
5907
5908 /* VEC is a vector of constructor elements built up for the base and member
5909 initializers of a constructor for TYPE. They need to be in increasing
5910 offset order, which they might not be yet if TYPE has a primary base
5911 which is not first in the base-clause or a vptr and at least one base
5912 all of which are non-primary. */
5913
VEC(constructor_elt,gc)5914 static VEC(constructor_elt,gc) *
5915 sort_constexpr_mem_initializers (tree type, VEC(constructor_elt,gc) *vec)
5916 {
5917 tree pri = CLASSTYPE_PRIMARY_BINFO (type);
5918 tree field_type;
5919 constructor_elt elt;
5920 int i;
5921
5922 if (pri)
5923 field_type = BINFO_TYPE (pri);
5924 else if (TYPE_CONTAINS_VPTR_P (type))
5925 field_type = vtbl_ptr_type_node;
5926 else
5927 return vec;
5928
5929 /* Find the element for the primary base or vptr and move it to the
5930 beginning of the vec. */
5931 for (i = 0; ; ++i)
5932 if (TREE_TYPE (VEC_index (constructor_elt, vec, i)->index) == field_type)
5933 break;
5934
5935 if (i > 0)
5936 {
5937 elt = *VEC_index (constructor_elt, vec, i);
5938 for (; i > 0; --i)
5939 VEC_replace (constructor_elt, vec, i,
5940 VEC_index (constructor_elt, vec, i-1));
5941 VEC_replace (constructor_elt, vec, 0, &elt);
5942 }
5943 return vec;
5944 }
5945
5946 /* Build compile-time evalable representations of member-initializer list
5947 for a constexpr constructor. */
5948
5949 static tree
build_constexpr_constructor_member_initializers(tree type,tree body)5950 build_constexpr_constructor_member_initializers (tree type, tree body)
5951 {
5952 VEC(constructor_elt,gc) *vec = NULL;
5953 bool ok = true;
5954 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR
5955 || TREE_CODE (body) == EH_SPEC_BLOCK)
5956 body = TREE_OPERAND (body, 0);
5957 if (TREE_CODE (body) == STATEMENT_LIST)
5958 body = STATEMENT_LIST_HEAD (body)->stmt;
5959 body = BIND_EXPR_BODY (body);
5960 if (TREE_CODE (body) == CLEANUP_POINT_EXPR)
5961 {
5962 body = TREE_OPERAND (body, 0);
5963 if (TREE_CODE (body) == EXPR_STMT)
5964 body = TREE_OPERAND (body, 0);
5965 if (TREE_CODE (body) == INIT_EXPR
5966 && (same_type_ignoring_top_level_qualifiers_p
5967 (TREE_TYPE (TREE_OPERAND (body, 0)),
5968 current_class_type)))
5969 {
5970 /* Trivial copy. */
5971 return TREE_OPERAND (body, 1);
5972 }
5973 ok = build_data_member_initialization (body, &vec);
5974 }
5975 else if (TREE_CODE (body) == STATEMENT_LIST)
5976 {
5977 tree_stmt_iterator i;
5978 for (i = tsi_start (body); !tsi_end_p (i); tsi_next (&i))
5979 {
5980 ok = build_data_member_initialization (tsi_stmt (i), &vec);
5981 if (!ok)
5982 break;
5983 }
5984 }
5985 else if (EXPR_P (body))
5986 ok = build_data_member_initialization (body, &vec);
5987 else
5988 gcc_assert (errorcount > 0);
5989 if (ok)
5990 {
5991 if (VEC_length (constructor_elt, vec) > 0)
5992 {
5993 /* In a delegating constructor, return the target. */
5994 constructor_elt *ce = VEC_index (constructor_elt, vec, 0);
5995 if (ce->index == current_class_ptr)
5996 {
5997 body = ce->value;
5998 VEC_free (constructor_elt, gc, vec);
5999 return body;
6000 }
6001 }
6002 vec = sort_constexpr_mem_initializers (type, vec);
6003 return build_constructor (type, vec);
6004 }
6005 else
6006 return error_mark_node;
6007 }
6008
6009 /* Subroutine of register_constexpr_fundef. BODY is the body of a function
6010 declared to be constexpr, or a sub-statement thereof. Returns the
6011 return value if suitable, error_mark_node for a statement not allowed in
6012 a constexpr function, or NULL_TREE if no return value was found. */
6013
6014 static tree
constexpr_fn_retval(tree body)6015 constexpr_fn_retval (tree body)
6016 {
6017 switch (TREE_CODE (body))
6018 {
6019 case STATEMENT_LIST:
6020 {
6021 tree_stmt_iterator i;
6022 tree expr = NULL_TREE;
6023 for (i = tsi_start (body); !tsi_end_p (i); tsi_next (&i))
6024 {
6025 tree s = constexpr_fn_retval (tsi_stmt (i));
6026 if (s == error_mark_node)
6027 return error_mark_node;
6028 else if (s == NULL_TREE)
6029 /* Keep iterating. */;
6030 else if (expr)
6031 /* Multiple return statements. */
6032 return error_mark_node;
6033 else
6034 expr = s;
6035 }
6036 return expr;
6037 }
6038
6039 case RETURN_EXPR:
6040 return unshare_expr (TREE_OPERAND (body, 0));
6041
6042 case DECL_EXPR:
6043 if (TREE_CODE (DECL_EXPR_DECL (body)) == USING_DECL)
6044 return NULL_TREE;
6045 return error_mark_node;
6046
6047 case CLEANUP_POINT_EXPR:
6048 return constexpr_fn_retval (TREE_OPERAND (body, 0));
6049
6050 case USING_STMT:
6051 return NULL_TREE;
6052
6053 default:
6054 return error_mark_node;
6055 }
6056 }
6057
6058 /* Subroutine of register_constexpr_fundef. BODY is the DECL_SAVED_TREE of
6059 FUN; do the necessary transformations to turn it into a single expression
6060 that we can store in the hash table. */
6061
6062 static tree
massage_constexpr_body(tree fun,tree body)6063 massage_constexpr_body (tree fun, tree body)
6064 {
6065 if (DECL_CONSTRUCTOR_P (fun))
6066 body = build_constexpr_constructor_member_initializers
6067 (DECL_CONTEXT (fun), body);
6068 else
6069 {
6070 if (TREE_CODE (body) == EH_SPEC_BLOCK)
6071 body = EH_SPEC_STMTS (body);
6072 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR)
6073 body = TREE_OPERAND (body, 0);
6074 if (TREE_CODE (body) == BIND_EXPR)
6075 body = BIND_EXPR_BODY (body);
6076 body = constexpr_fn_retval (body);
6077 }
6078 return body;
6079 }
6080
6081 /* FUN is a constexpr constructor with massaged body BODY. Return true
6082 if some bases/fields are uninitialized, and complain if COMPLAIN. */
6083
6084 static bool
cx_check_missing_mem_inits(tree fun,tree body,bool complain)6085 cx_check_missing_mem_inits (tree fun, tree body, bool complain)
6086 {
6087 bool bad;
6088 tree field;
6089 unsigned i, nelts;
6090 tree ctype;
6091
6092 if (TREE_CODE (body) != CONSTRUCTOR)
6093 return false;
6094
6095 nelts = CONSTRUCTOR_NELTS (body);
6096 ctype = DECL_CONTEXT (fun);
6097 field = TYPE_FIELDS (ctype);
6098
6099 if (TREE_CODE (ctype) == UNION_TYPE)
6100 {
6101 if (nelts == 0 && next_initializable_field (field))
6102 {
6103 if (complain)
6104 error ("%<constexpr%> constructor for union %qT must "
6105 "initialize exactly one non-static data member", ctype);
6106 return true;
6107 }
6108 return false;
6109 }
6110
6111 bad = false;
6112 for (i = 0; i <= nelts; ++i)
6113 {
6114 tree index;
6115 if (i == nelts)
6116 index = NULL_TREE;
6117 else
6118 {
6119 index = CONSTRUCTOR_ELT (body, i)->index;
6120 /* Skip base and vtable inits. */
6121 if (TREE_CODE (index) != FIELD_DECL
6122 || DECL_ARTIFICIAL (index))
6123 continue;
6124 }
6125 for (; field != index; field = DECL_CHAIN (field))
6126 {
6127 tree ftype;
6128 if (TREE_CODE (field) != FIELD_DECL
6129 || (DECL_C_BIT_FIELD (field) && !DECL_NAME (field))
6130 || DECL_ARTIFICIAL (field))
6131 continue;
6132 ftype = strip_array_types (TREE_TYPE (field));
6133 if (type_has_constexpr_default_constructor (ftype))
6134 {
6135 /* It's OK to skip a member with a trivial constexpr ctor.
6136 A constexpr ctor that isn't trivial should have been
6137 added in by now. */
6138 gcc_checking_assert (!TYPE_HAS_COMPLEX_DFLT (ftype)
6139 || errorcount != 0);
6140 continue;
6141 }
6142 if (!complain)
6143 return true;
6144 error ("uninitialized member %qD in %<constexpr%> constructor",
6145 field);
6146 bad = true;
6147 }
6148 if (field == NULL_TREE)
6149 break;
6150 field = DECL_CHAIN (field);
6151 }
6152
6153 return bad;
6154 }
6155
6156 /* We are processing the definition of the constexpr function FUN.
6157 Check that its BODY fulfills the propriate requirements and
6158 enter it in the constexpr function definition table.
6159 For constructor BODY is actually the TREE_LIST of the
6160 member-initializer list. */
6161
6162 tree
register_constexpr_fundef(tree fun,tree body)6163 register_constexpr_fundef (tree fun, tree body)
6164 {
6165 constexpr_fundef entry;
6166 constexpr_fundef **slot;
6167
6168 if (!is_valid_constexpr_fn (fun, !DECL_GENERATED_P (fun)))
6169 return NULL;
6170
6171 body = massage_constexpr_body (fun, body);
6172 if (body == NULL_TREE || body == error_mark_node)
6173 {
6174 if (!DECL_CONSTRUCTOR_P (fun))
6175 error ("body of constexpr function %qD not a return-statement", fun);
6176 return NULL;
6177 }
6178
6179 if (!potential_rvalue_constant_expression (body))
6180 {
6181 if (!DECL_GENERATED_P (fun))
6182 require_potential_rvalue_constant_expression (body);
6183 return NULL;
6184 }
6185
6186 if (DECL_CONSTRUCTOR_P (fun)
6187 && cx_check_missing_mem_inits (fun, body, !DECL_GENERATED_P (fun)))
6188 return NULL;
6189
6190 /* Create the constexpr function table if necessary. */
6191 if (constexpr_fundef_table == NULL)
6192 constexpr_fundef_table = htab_create_ggc (101,
6193 constexpr_fundef_hash,
6194 constexpr_fundef_equal,
6195 ggc_free);
6196 entry.decl = fun;
6197 entry.body = body;
6198 slot = (constexpr_fundef **)
6199 htab_find_slot (constexpr_fundef_table, &entry, INSERT);
6200
6201 gcc_assert (*slot == NULL);
6202 *slot = ggc_alloc_constexpr_fundef ();
6203 **slot = entry;
6204
6205 return fun;
6206 }
6207
6208 /* FUN is a non-constexpr function called in a context that requires a
6209 constant expression. If it comes from a constexpr template, explain why
6210 the instantiation isn't constexpr. */
6211
6212 void
explain_invalid_constexpr_fn(tree fun)6213 explain_invalid_constexpr_fn (tree fun)
6214 {
6215 static struct pointer_set_t *diagnosed;
6216 tree body;
6217 location_t save_loc;
6218 /* Only diagnose defaulted functions or instantiations. */
6219 if (!DECL_DEFAULTED_FN (fun)
6220 && !is_instantiation_of_constexpr (fun))
6221 return;
6222 if (diagnosed == NULL)
6223 diagnosed = pointer_set_create ();
6224 if (pointer_set_insert (diagnosed, fun) != 0)
6225 /* Already explained. */
6226 return;
6227
6228 save_loc = input_location;
6229 input_location = DECL_SOURCE_LOCATION (fun);
6230 inform (0, "%q+D is not usable as a constexpr function because:", fun);
6231 /* First check the declaration. */
6232 if (is_valid_constexpr_fn (fun, true))
6233 {
6234 /* Then if it's OK, the body. */
6235 if (DECL_DEFAULTED_FN (fun))
6236 explain_implicit_non_constexpr (fun);
6237 else
6238 {
6239 body = massage_constexpr_body (fun, DECL_SAVED_TREE (fun));
6240 require_potential_rvalue_constant_expression (body);
6241 if (DECL_CONSTRUCTOR_P (fun))
6242 cx_check_missing_mem_inits (fun, body, true);
6243 }
6244 }
6245 input_location = save_loc;
6246 }
6247
6248 /* Objects of this type represent calls to constexpr functions
6249 along with the bindings of parameters to their arguments, for
6250 the purpose of compile time evaluation. */
6251
6252 typedef struct GTY(()) constexpr_call {
6253 /* Description of the constexpr function definition. */
6254 constexpr_fundef *fundef;
6255 /* Parameter bindings enironment. A TREE_LIST where each TREE_PURPOSE
6256 is a parameter _DECL and the TREE_VALUE is the value of the parameter.
6257 Note: This arrangement is made to accomodate the use of
6258 iterative_hash_template_arg (see pt.c). If you change this
6259 representation, also change the hash calculation in
6260 cxx_eval_call_expression. */
6261 tree bindings;
6262 /* Result of the call.
6263 NULL means the call is being evaluated.
6264 error_mark_node means that the evaluation was erroneous;
6265 otherwise, the actuall value of the call. */
6266 tree result;
6267 /* The hash of this call; we remember it here to avoid having to
6268 recalculate it when expanding the hash table. */
6269 hashval_t hash;
6270 } constexpr_call;
6271
6272 /* A table of all constexpr calls that have been evaluated by the
6273 compiler in this translation unit. */
6274
6275 static GTY ((param_is (constexpr_call))) htab_t constexpr_call_table;
6276
6277 static tree cxx_eval_constant_expression (const constexpr_call *, tree,
6278 bool, bool, bool *);
6279
6280 /* Compute a hash value for a constexpr call representation. */
6281
6282 static hashval_t
constexpr_call_hash(const void * p)6283 constexpr_call_hash (const void *p)
6284 {
6285 const constexpr_call *info = (const constexpr_call *) p;
6286 return info->hash;
6287 }
6288
6289 /* Return 1 if the objects pointed to by P and Q represent calls
6290 to the same constexpr function with the same arguments.
6291 Otherwise, return 0. */
6292
6293 static int
constexpr_call_equal(const void * p,const void * q)6294 constexpr_call_equal (const void *p, const void *q)
6295 {
6296 const constexpr_call *lhs = (const constexpr_call *) p;
6297 const constexpr_call *rhs = (const constexpr_call *) q;
6298 tree lhs_bindings;
6299 tree rhs_bindings;
6300 if (lhs == rhs)
6301 return 1;
6302 if (!constexpr_fundef_equal (lhs->fundef, rhs->fundef))
6303 return 0;
6304 lhs_bindings = lhs->bindings;
6305 rhs_bindings = rhs->bindings;
6306 while (lhs_bindings != NULL && rhs_bindings != NULL)
6307 {
6308 tree lhs_arg = TREE_VALUE (lhs_bindings);
6309 tree rhs_arg = TREE_VALUE (rhs_bindings);
6310 gcc_assert (TREE_TYPE (lhs_arg) == TREE_TYPE (rhs_arg));
6311 if (!cp_tree_equal (lhs_arg, rhs_arg))
6312 return 0;
6313 lhs_bindings = TREE_CHAIN (lhs_bindings);
6314 rhs_bindings = TREE_CHAIN (rhs_bindings);
6315 }
6316 return lhs_bindings == rhs_bindings;
6317 }
6318
6319 /* Initialize the constexpr call table, if needed. */
6320
6321 static void
maybe_initialize_constexpr_call_table(void)6322 maybe_initialize_constexpr_call_table (void)
6323 {
6324 if (constexpr_call_table == NULL)
6325 constexpr_call_table = htab_create_ggc (101,
6326 constexpr_call_hash,
6327 constexpr_call_equal,
6328 ggc_free);
6329 }
6330
6331 /* Return true if T designates the implied `this' parameter. */
6332
6333 static inline bool
is_this_parameter(tree t)6334 is_this_parameter (tree t)
6335 {
6336 return t == current_class_ptr;
6337 }
6338
6339 /* We have an expression tree T that represents a call, either CALL_EXPR
6340 or AGGR_INIT_EXPR. If the call is lexically to a named function,
6341 retrun the _DECL for that function. */
6342
6343 static tree
get_function_named_in_call(tree t)6344 get_function_named_in_call (tree t)
6345 {
6346 tree fun = NULL;
6347 switch (TREE_CODE (t))
6348 {
6349 case CALL_EXPR:
6350 fun = CALL_EXPR_FN (t);
6351 break;
6352
6353 case AGGR_INIT_EXPR:
6354 fun = AGGR_INIT_EXPR_FN (t);
6355 break;
6356
6357 default:
6358 gcc_unreachable();
6359 break;
6360 }
6361 if (TREE_CODE (fun) == ADDR_EXPR
6362 && TREE_CODE (TREE_OPERAND (fun, 0)) == FUNCTION_DECL)
6363 fun = TREE_OPERAND (fun, 0);
6364 return fun;
6365 }
6366
6367 /* We have an expression tree T that represents a call, either CALL_EXPR
6368 or AGGR_INIT_EXPR. Return the Nth argument. */
6369
6370 static inline tree
get_nth_callarg(tree t,int n)6371 get_nth_callarg (tree t, int n)
6372 {
6373 switch (TREE_CODE (t))
6374 {
6375 case CALL_EXPR:
6376 return CALL_EXPR_ARG (t, n);
6377
6378 case AGGR_INIT_EXPR:
6379 return AGGR_INIT_EXPR_ARG (t, n);
6380
6381 default:
6382 gcc_unreachable ();
6383 return NULL;
6384 }
6385 }
6386
6387 /* Look up the binding of the function parameter T in a constexpr
6388 function call context CALL. */
6389
6390 static tree
lookup_parameter_binding(const constexpr_call * call,tree t)6391 lookup_parameter_binding (const constexpr_call *call, tree t)
6392 {
6393 tree b = purpose_member (t, call->bindings);
6394 return TREE_VALUE (b);
6395 }
6396
6397 /* Attempt to evaluate T which represents a call to a builtin function.
6398 We assume here that all builtin functions evaluate to scalar types
6399 represented by _CST nodes. */
6400
6401 static tree
cxx_eval_builtin_function_call(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)6402 cxx_eval_builtin_function_call (const constexpr_call *call, tree t,
6403 bool allow_non_constant, bool addr,
6404 bool *non_constant_p)
6405 {
6406 const int nargs = call_expr_nargs (t);
6407 tree *args = (tree *) alloca (nargs * sizeof (tree));
6408 tree new_call;
6409 int i;
6410 for (i = 0; i < nargs; ++i)
6411 {
6412 args[i] = cxx_eval_constant_expression (call, CALL_EXPR_ARG (t, i),
6413 allow_non_constant, addr,
6414 non_constant_p);
6415 if (allow_non_constant && *non_constant_p)
6416 return t;
6417 }
6418 if (*non_constant_p)
6419 return t;
6420 new_call = build_call_array_loc (EXPR_LOCATION (t), TREE_TYPE (t),
6421 CALL_EXPR_FN (t), nargs, args);
6422 return fold (new_call);
6423 }
6424
6425 /* TEMP is the constant value of a temporary object of type TYPE. Adjust
6426 the type of the value to match. */
6427
6428 static tree
adjust_temp_type(tree type,tree temp)6429 adjust_temp_type (tree type, tree temp)
6430 {
6431 if (TREE_TYPE (temp) == type)
6432 return temp;
6433 /* Avoid wrapping an aggregate value in a NOP_EXPR. */
6434 if (TREE_CODE (temp) == CONSTRUCTOR)
6435 return build_constructor (type, CONSTRUCTOR_ELTS (temp));
6436 gcc_assert (SCALAR_TYPE_P (type));
6437 return cp_fold_convert (type, temp);
6438 }
6439
6440 /* Subroutine of cxx_eval_call_expression.
6441 We are processing a call expression (either CALL_EXPR or
6442 AGGR_INIT_EXPR) in the call context of OLD_CALL. Evaluate
6443 all arguments and bind their values to correspondings
6444 parameters, making up the NEW_CALL context. */
6445
6446 static void
cxx_bind_parameters_in_call(const constexpr_call * old_call,tree t,constexpr_call * new_call,bool allow_non_constant,bool * non_constant_p)6447 cxx_bind_parameters_in_call (const constexpr_call *old_call, tree t,
6448 constexpr_call *new_call,
6449 bool allow_non_constant,
6450 bool *non_constant_p)
6451 {
6452 const int nargs = call_expr_nargs (t);
6453 tree fun = new_call->fundef->decl;
6454 tree parms = DECL_ARGUMENTS (fun);
6455 int i;
6456 for (i = 0; i < nargs; ++i)
6457 {
6458 tree x, arg;
6459 tree type = parms ? TREE_TYPE (parms) : void_type_node;
6460 /* For member function, the first argument is a pointer to the implied
6461 object. And for an object contruction, don't bind `this' before
6462 it is fully constructed. */
6463 if (i == 0 && DECL_CONSTRUCTOR_P (fun))
6464 goto next;
6465 x = get_nth_callarg (t, i);
6466 arg = cxx_eval_constant_expression (old_call, x, allow_non_constant,
6467 TREE_CODE (type) == REFERENCE_TYPE,
6468 non_constant_p);
6469 /* Don't VERIFY_CONSTANT here. */
6470 if (*non_constant_p && allow_non_constant)
6471 return;
6472 /* Just discard ellipsis args after checking their constantitude. */
6473 if (!parms)
6474 continue;
6475 if (*non_constant_p)
6476 /* Don't try to adjust the type of non-constant args. */
6477 goto next;
6478
6479 /* Make sure the binding has the same type as the parm. */
6480 if (TREE_CODE (type) != REFERENCE_TYPE)
6481 arg = adjust_temp_type (type, arg);
6482 new_call->bindings = tree_cons (parms, arg, new_call->bindings);
6483 next:
6484 parms = TREE_CHAIN (parms);
6485 }
6486 }
6487
6488 /* Variables and functions to manage constexpr call expansion context.
6489 These do not need to be marked for PCH or GC. */
6490
6491 /* FIXME remember and print actual constant arguments. */
6492 static VEC(tree,heap) *call_stack = NULL;
6493 static int call_stack_tick;
6494 static int last_cx_error_tick;
6495
6496 static bool
push_cx_call_context(tree call)6497 push_cx_call_context (tree call)
6498 {
6499 ++call_stack_tick;
6500 if (!EXPR_HAS_LOCATION (call))
6501 SET_EXPR_LOCATION (call, input_location);
6502 VEC_safe_push (tree, heap, call_stack, call);
6503 if (VEC_length (tree, call_stack) > (unsigned) max_constexpr_depth)
6504 return false;
6505 return true;
6506 }
6507
6508 static void
pop_cx_call_context(void)6509 pop_cx_call_context (void)
6510 {
6511 ++call_stack_tick;
6512 VEC_pop (tree, call_stack);
6513 }
6514
VEC(tree,heap)6515 VEC(tree,heap) *
6516 cx_error_context (void)
6517 {
6518 VEC(tree,heap) *r = NULL;
6519 if (call_stack_tick != last_cx_error_tick
6520 && !VEC_empty (tree, call_stack))
6521 r = call_stack;
6522 last_cx_error_tick = call_stack_tick;
6523 return r;
6524 }
6525
6526 /* Subroutine of cxx_eval_constant_expression.
6527 Evaluate the call expression tree T in the context of OLD_CALL expression
6528 evaluation. */
6529
6530 static tree
cxx_eval_call_expression(const constexpr_call * old_call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)6531 cxx_eval_call_expression (const constexpr_call *old_call, tree t,
6532 bool allow_non_constant, bool addr,
6533 bool *non_constant_p)
6534 {
6535 location_t loc = EXPR_LOC_OR_HERE (t);
6536 tree fun = get_function_named_in_call (t);
6537 tree result;
6538 constexpr_call new_call = { NULL, NULL, NULL, 0 };
6539 constexpr_call **slot;
6540 constexpr_call *entry;
6541 bool depth_ok;
6542
6543 if (TREE_CODE (fun) != FUNCTION_DECL)
6544 {
6545 /* Might be a constexpr function pointer. */
6546 fun = cxx_eval_constant_expression (old_call, fun, allow_non_constant,
6547 /*addr*/false, non_constant_p);
6548 if (TREE_CODE (fun) == ADDR_EXPR)
6549 fun = TREE_OPERAND (fun, 0);
6550 }
6551 if (TREE_CODE (fun) != FUNCTION_DECL)
6552 {
6553 if (!allow_non_constant && !*non_constant_p)
6554 error_at (loc, "expression %qE does not designate a constexpr "
6555 "function", fun);
6556 *non_constant_p = true;
6557 return t;
6558 }
6559 if (DECL_CLONED_FUNCTION_P (fun))
6560 fun = DECL_CLONED_FUNCTION (fun);
6561 if (is_builtin_fn (fun))
6562 return cxx_eval_builtin_function_call (old_call, t, allow_non_constant,
6563 addr, non_constant_p);
6564 if (!DECL_DECLARED_CONSTEXPR_P (fun))
6565 {
6566 if (!allow_non_constant)
6567 {
6568 error_at (loc, "call to non-constexpr function %qD", fun);
6569 explain_invalid_constexpr_fn (fun);
6570 }
6571 *non_constant_p = true;
6572 return t;
6573 }
6574
6575 /* Shortcut trivial copy constructor/op=. */
6576 if (call_expr_nargs (t) == 2 && trivial_fn_p (fun))
6577 {
6578 tree arg = convert_from_reference (get_nth_callarg (t, 1));
6579 return cxx_eval_constant_expression (old_call, arg, allow_non_constant,
6580 addr, non_constant_p);
6581 }
6582
6583 /* If in direct recursive call, optimize definition search. */
6584 if (old_call != NULL && old_call->fundef->decl == fun)
6585 new_call.fundef = old_call->fundef;
6586 else
6587 {
6588 new_call.fundef = retrieve_constexpr_fundef (fun);
6589 if (new_call.fundef == NULL || new_call.fundef->body == NULL)
6590 {
6591 if (!allow_non_constant)
6592 {
6593 if (DECL_INITIAL (fun))
6594 {
6595 /* The definition of fun was somehow unsuitable. */
6596 error_at (loc, "%qD called in a constant expression", fun);
6597 explain_invalid_constexpr_fn (fun);
6598 }
6599 else
6600 error_at (loc, "%qD used before its definition", fun);
6601 }
6602 *non_constant_p = true;
6603 return t;
6604 }
6605 }
6606 cxx_bind_parameters_in_call (old_call, t, &new_call,
6607 allow_non_constant, non_constant_p);
6608 if (*non_constant_p)
6609 return t;
6610
6611 depth_ok = push_cx_call_context (t);
6612
6613 new_call.hash
6614 = iterative_hash_template_arg (new_call.bindings,
6615 constexpr_fundef_hash (new_call.fundef));
6616
6617 /* If we have seen this call before, we are done. */
6618 maybe_initialize_constexpr_call_table ();
6619 slot = (constexpr_call **)
6620 htab_find_slot (constexpr_call_table, &new_call, INSERT);
6621 entry = *slot;
6622 if (entry == NULL)
6623 {
6624 /* We need to keep a pointer to the entry, not just the slot, as the
6625 slot can move in the call to cxx_eval_builtin_function_call. */
6626 *slot = entry = ggc_alloc_constexpr_call ();
6627 *entry = new_call;
6628 }
6629 /* Calls which are in progress have their result set to NULL
6630 so that we can detect circular dependencies. */
6631 else if (entry->result == NULL)
6632 {
6633 if (!allow_non_constant)
6634 error ("call has circular dependency");
6635 *non_constant_p = true;
6636 entry->result = result = error_mark_node;
6637 }
6638
6639 if (!depth_ok)
6640 {
6641 if (!allow_non_constant)
6642 error ("constexpr evaluation depth exceeds maximum of %d (use "
6643 "-fconstexpr-depth= to increase the maximum)",
6644 max_constexpr_depth);
6645 *non_constant_p = true;
6646 entry->result = result = error_mark_node;
6647 }
6648 else
6649 {
6650 result = entry->result;
6651 if (!result || result == error_mark_node)
6652 result = (cxx_eval_constant_expression
6653 (&new_call, new_call.fundef->body,
6654 allow_non_constant, addr,
6655 non_constant_p));
6656 if (result == error_mark_node)
6657 *non_constant_p = true;
6658 if (*non_constant_p)
6659 entry->result = result = error_mark_node;
6660 else
6661 {
6662 /* If this was a call to initialize an object, set the type of
6663 the CONSTRUCTOR to the type of that object. */
6664 if (DECL_CONSTRUCTOR_P (fun))
6665 {
6666 tree ob_arg = get_nth_callarg (t, 0);
6667 STRIP_NOPS (ob_arg);
6668 gcc_assert (TREE_CODE (TREE_TYPE (ob_arg)) == POINTER_TYPE
6669 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (ob_arg))));
6670 result = adjust_temp_type (TREE_TYPE (TREE_TYPE (ob_arg)),
6671 result);
6672 }
6673 entry->result = result;
6674 }
6675 }
6676
6677 pop_cx_call_context ();
6678 return unshare_expr (result);
6679 }
6680
6681 /* FIXME speed this up, it's taking 16% of compile time on sieve testcase. */
6682
6683 bool
reduced_constant_expression_p(tree t)6684 reduced_constant_expression_p (tree t)
6685 {
6686 if (TREE_OVERFLOW_P (t))
6687 /* Integer overflow makes this not a constant expression. */
6688 return false;
6689 /* FIXME are we calling this too much? */
6690 return initializer_constant_valid_p (t, TREE_TYPE (t)) != NULL_TREE;
6691 }
6692
6693 /* Some expressions may have constant operands but are not constant
6694 themselves, such as 1/0. Call this function (or rather, the macro
6695 following it) to check for that condition.
6696
6697 We only call this in places that require an arithmetic constant, not in
6698 places where we might have a non-constant expression that can be a
6699 component of a constant expression, such as the address of a constexpr
6700 variable that might be dereferenced later. */
6701
6702 static bool
verify_constant(tree t,bool allow_non_constant,bool * non_constant_p)6703 verify_constant (tree t, bool allow_non_constant, bool *non_constant_p)
6704 {
6705 if (!*non_constant_p && !reduced_constant_expression_p (t))
6706 {
6707 if (!allow_non_constant)
6708 {
6709 /* If T was already folded to a _CST with TREE_OVERFLOW set,
6710 printing the folded constant isn't helpful. */
6711 if (TREE_OVERFLOW_P (t))
6712 {
6713 permerror (input_location, "overflow in constant expression");
6714 /* If we're being permissive (and are in an enforcing
6715 context), consider this constant. */
6716 if (flag_permissive)
6717 return false;
6718 }
6719 else
6720 error ("%q+E is not a constant expression", t);
6721 }
6722 *non_constant_p = true;
6723 }
6724 return *non_constant_p;
6725 }
6726 #define VERIFY_CONSTANT(X) \
6727 do { \
6728 if (verify_constant ((X), allow_non_constant, non_constant_p)) \
6729 return t; \
6730 } while (0)
6731
6732 /* Subroutine of cxx_eval_constant_expression.
6733 Attempt to reduce the unary expression tree T to a compile time value.
6734 If successful, return the value. Otherwise issue a diagnostic
6735 and return error_mark_node. */
6736
6737 static tree
cxx_eval_unary_expression(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)6738 cxx_eval_unary_expression (const constexpr_call *call, tree t,
6739 bool allow_non_constant, bool addr,
6740 bool *non_constant_p)
6741 {
6742 tree r;
6743 tree orig_arg = TREE_OPERAND (t, 0);
6744 tree arg = cxx_eval_constant_expression (call, orig_arg, allow_non_constant,
6745 addr, non_constant_p);
6746 VERIFY_CONSTANT (arg);
6747 if (arg == orig_arg)
6748 return t;
6749 r = fold_build1 (TREE_CODE (t), TREE_TYPE (t), arg);
6750 VERIFY_CONSTANT (r);
6751 return r;
6752 }
6753
6754 /* Subroutine of cxx_eval_constant_expression.
6755 Like cxx_eval_unary_expression, except for binary expressions. */
6756
6757 static tree
cxx_eval_binary_expression(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)6758 cxx_eval_binary_expression (const constexpr_call *call, tree t,
6759 bool allow_non_constant, bool addr,
6760 bool *non_constant_p)
6761 {
6762 tree r;
6763 tree orig_lhs = TREE_OPERAND (t, 0);
6764 tree orig_rhs = TREE_OPERAND (t, 1);
6765 tree lhs, rhs;
6766 lhs = cxx_eval_constant_expression (call, orig_lhs,
6767 allow_non_constant, addr,
6768 non_constant_p);
6769 VERIFY_CONSTANT (lhs);
6770 rhs = cxx_eval_constant_expression (call, orig_rhs,
6771 allow_non_constant, addr,
6772 non_constant_p);
6773 VERIFY_CONSTANT (rhs);
6774 if (lhs == orig_lhs && rhs == orig_rhs)
6775 return t;
6776 r = fold_build2 (TREE_CODE (t), TREE_TYPE (t), lhs, rhs);
6777 VERIFY_CONSTANT (r);
6778 return r;
6779 }
6780
6781 /* Subroutine of cxx_eval_constant_expression.
6782 Attempt to evaluate condition expressions. Dead branches are not
6783 looked into. */
6784
6785 static tree
cxx_eval_conditional_expression(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)6786 cxx_eval_conditional_expression (const constexpr_call *call, tree t,
6787 bool allow_non_constant, bool addr,
6788 bool *non_constant_p)
6789 {
6790 tree val = cxx_eval_constant_expression (call, TREE_OPERAND (t, 0),
6791 allow_non_constant, addr,
6792 non_constant_p);
6793 VERIFY_CONSTANT (val);
6794 /* Don't VERIFY_CONSTANT the other operands. */
6795 if (integer_zerop (val))
6796 return cxx_eval_constant_expression (call, TREE_OPERAND (t, 2),
6797 allow_non_constant, addr,
6798 non_constant_p);
6799 return cxx_eval_constant_expression (call, TREE_OPERAND (t, 1),
6800 allow_non_constant, addr,
6801 non_constant_p);
6802 }
6803
6804 /* Subroutine of cxx_eval_constant_expression.
6805 Attempt to reduce a reference to an array slot. */
6806
6807 static tree
cxx_eval_array_reference(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)6808 cxx_eval_array_reference (const constexpr_call *call, tree t,
6809 bool allow_non_constant, bool addr,
6810 bool *non_constant_p)
6811 {
6812 tree oldary = TREE_OPERAND (t, 0);
6813 tree ary = cxx_eval_constant_expression (call, oldary,
6814 allow_non_constant, addr,
6815 non_constant_p);
6816 tree index, oldidx;
6817 HOST_WIDE_INT i;
6818 tree elem_type;
6819 unsigned len, elem_nchars = 1;
6820 if (*non_constant_p)
6821 return t;
6822 oldidx = TREE_OPERAND (t, 1);
6823 index = cxx_eval_constant_expression (call, oldidx,
6824 allow_non_constant, false,
6825 non_constant_p);
6826 VERIFY_CONSTANT (index);
6827 if (addr && ary == oldary && index == oldidx)
6828 return t;
6829 else if (addr)
6830 return build4 (ARRAY_REF, TREE_TYPE (t), ary, index, NULL, NULL);
6831 elem_type = TREE_TYPE (TREE_TYPE (ary));
6832 if (TREE_CODE (ary) == CONSTRUCTOR)
6833 len = CONSTRUCTOR_NELTS (ary);
6834 else if (TREE_CODE (ary) == STRING_CST)
6835 {
6836 elem_nchars = (TYPE_PRECISION (elem_type)
6837 / TYPE_PRECISION (char_type_node));
6838 len = (unsigned) TREE_STRING_LENGTH (ary) / elem_nchars;
6839 }
6840 else
6841 {
6842 /* We can't do anything with other tree codes, so use
6843 VERIFY_CONSTANT to complain and fail. */
6844 VERIFY_CONSTANT (ary);
6845 gcc_unreachable ();
6846 }
6847 if (compare_tree_int (index, len) >= 0)
6848 {
6849 if (tree_int_cst_lt (index, array_type_nelts_top (TREE_TYPE (ary))))
6850 {
6851 /* If it's within the array bounds but doesn't have an explicit
6852 initializer, it's value-initialized. */
6853 tree val = build_value_init (elem_type, tf_warning_or_error);
6854 return cxx_eval_constant_expression (call, val,
6855 allow_non_constant, addr,
6856 non_constant_p);
6857 }
6858
6859 if (!allow_non_constant)
6860 error ("array subscript out of bound");
6861 *non_constant_p = true;
6862 return t;
6863 }
6864 i = tree_low_cst (index, 0);
6865 if (TREE_CODE (ary) == CONSTRUCTOR)
6866 return VEC_index (constructor_elt, CONSTRUCTOR_ELTS (ary), i)->value;
6867 else if (elem_nchars == 1)
6868 return build_int_cst (cv_unqualified (TREE_TYPE (TREE_TYPE (ary))),
6869 TREE_STRING_POINTER (ary)[i]);
6870 else
6871 {
6872 tree type = cv_unqualified (TREE_TYPE (TREE_TYPE (ary)));
6873 return native_interpret_expr (type, (const unsigned char *)
6874 TREE_STRING_POINTER (ary)
6875 + i * elem_nchars, elem_nchars);
6876 }
6877 /* Don't VERIFY_CONSTANT here. */
6878 }
6879
6880 /* Subroutine of cxx_eval_constant_expression.
6881 Attempt to reduce a field access of a value of class type. */
6882
6883 static tree
cxx_eval_component_reference(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)6884 cxx_eval_component_reference (const constexpr_call *call, tree t,
6885 bool allow_non_constant, bool addr,
6886 bool *non_constant_p)
6887 {
6888 unsigned HOST_WIDE_INT i;
6889 tree field;
6890 tree value;
6891 tree part = TREE_OPERAND (t, 1);
6892 tree orig_whole = TREE_OPERAND (t, 0);
6893 tree whole = cxx_eval_constant_expression (call, orig_whole,
6894 allow_non_constant, addr,
6895 non_constant_p);
6896 if (whole == orig_whole)
6897 return t;
6898 if (addr)
6899 return fold_build3 (COMPONENT_REF, TREE_TYPE (t),
6900 whole, part, NULL_TREE);
6901 /* Don't VERIFY_CONSTANT here; we only want to check that we got a
6902 CONSTRUCTOR. */
6903 if (!*non_constant_p && TREE_CODE (whole) != CONSTRUCTOR)
6904 {
6905 if (!allow_non_constant)
6906 error ("%qE is not a constant expression", orig_whole);
6907 *non_constant_p = true;
6908 }
6909 if (DECL_MUTABLE_P (part))
6910 {
6911 if (!allow_non_constant)
6912 error ("mutable %qD is not usable in a constant expression", part);
6913 *non_constant_p = true;
6914 }
6915 if (*non_constant_p)
6916 return t;
6917 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (whole), i, field, value)
6918 {
6919 if (field == part)
6920 return value;
6921 }
6922 if (TREE_CODE (TREE_TYPE (whole)) == UNION_TYPE
6923 && CONSTRUCTOR_NELTS (whole) > 0)
6924 {
6925 /* DR 1188 says we don't have to deal with this. */
6926 if (!allow_non_constant)
6927 error ("accessing %qD member instead of initialized %qD member in "
6928 "constant expression", part, CONSTRUCTOR_ELT (whole, 0)->index);
6929 *non_constant_p = true;
6930 return t;
6931 }
6932
6933 /* If there's no explicit init for this field, it's value-initialized. */
6934 value = build_value_init (TREE_TYPE (t), tf_warning_or_error);
6935 return cxx_eval_constant_expression (call, value,
6936 allow_non_constant, addr,
6937 non_constant_p);
6938 }
6939
6940 /* Subroutine of cxx_eval_constant_expression.
6941 Attempt to reduce a field access of a value of class type that is
6942 expressed as a BIT_FIELD_REF. */
6943
6944 static tree
cxx_eval_bit_field_ref(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)6945 cxx_eval_bit_field_ref (const constexpr_call *call, tree t,
6946 bool allow_non_constant, bool addr,
6947 bool *non_constant_p)
6948 {
6949 tree orig_whole = TREE_OPERAND (t, 0);
6950 tree retval, fldval, utype, mask;
6951 bool fld_seen = false;
6952 HOST_WIDE_INT istart, isize;
6953 tree whole = cxx_eval_constant_expression (call, orig_whole,
6954 allow_non_constant, addr,
6955 non_constant_p);
6956 tree start, field, value;
6957 unsigned HOST_WIDE_INT i;
6958
6959 if (whole == orig_whole)
6960 return t;
6961 /* Don't VERIFY_CONSTANT here; we only want to check that we got a
6962 CONSTRUCTOR. */
6963 if (!*non_constant_p && TREE_CODE (whole) != CONSTRUCTOR)
6964 {
6965 if (!allow_non_constant)
6966 error ("%qE is not a constant expression", orig_whole);
6967 *non_constant_p = true;
6968 }
6969 if (*non_constant_p)
6970 return t;
6971
6972 start = TREE_OPERAND (t, 2);
6973 istart = tree_low_cst (start, 0);
6974 isize = tree_low_cst (TREE_OPERAND (t, 1), 0);
6975 utype = TREE_TYPE (t);
6976 if (!TYPE_UNSIGNED (utype))
6977 utype = build_nonstandard_integer_type (TYPE_PRECISION (utype), 1);
6978 retval = build_int_cst (utype, 0);
6979 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (whole), i, field, value)
6980 {
6981 tree bitpos = bit_position (field);
6982 if (bitpos == start && DECL_SIZE (field) == TREE_OPERAND (t, 1))
6983 return value;
6984 if (TREE_CODE (TREE_TYPE (field)) == INTEGER_TYPE
6985 && TREE_CODE (value) == INTEGER_CST
6986 && host_integerp (bitpos, 0)
6987 && host_integerp (DECL_SIZE (field), 0))
6988 {
6989 HOST_WIDE_INT bit = tree_low_cst (bitpos, 0);
6990 HOST_WIDE_INT sz = tree_low_cst (DECL_SIZE (field), 0);
6991 HOST_WIDE_INT shift;
6992 if (bit >= istart && bit + sz <= istart + isize)
6993 {
6994 fldval = fold_convert (utype, value);
6995 mask = build_int_cst_type (utype, -1);
6996 mask = fold_build2 (LSHIFT_EXPR, utype, mask,
6997 size_int (TYPE_PRECISION (utype) - sz));
6998 mask = fold_build2 (RSHIFT_EXPR, utype, mask,
6999 size_int (TYPE_PRECISION (utype) - sz));
7000 fldval = fold_build2 (BIT_AND_EXPR, utype, fldval, mask);
7001 shift = bit - istart;
7002 if (BYTES_BIG_ENDIAN)
7003 shift = TYPE_PRECISION (utype) - shift - sz;
7004 fldval = fold_build2 (LSHIFT_EXPR, utype, fldval,
7005 size_int (shift));
7006 retval = fold_build2 (BIT_IOR_EXPR, utype, retval, fldval);
7007 fld_seen = true;
7008 }
7009 }
7010 }
7011 if (fld_seen)
7012 return fold_convert (TREE_TYPE (t), retval);
7013 gcc_unreachable ();
7014 return error_mark_node;
7015 }
7016
7017 /* Subroutine of cxx_eval_constant_expression.
7018 Evaluate a short-circuited logical expression T in the context
7019 of a given constexpr CALL. BAILOUT_VALUE is the value for
7020 early return. CONTINUE_VALUE is used here purely for
7021 sanity check purposes. */
7022
7023 static tree
cxx_eval_logical_expression(const constexpr_call * call,tree t,tree bailout_value,tree continue_value,bool allow_non_constant,bool addr,bool * non_constant_p)7024 cxx_eval_logical_expression (const constexpr_call *call, tree t,
7025 tree bailout_value, tree continue_value,
7026 bool allow_non_constant, bool addr,
7027 bool *non_constant_p)
7028 {
7029 tree r;
7030 tree lhs = cxx_eval_constant_expression (call, TREE_OPERAND (t, 0),
7031 allow_non_constant, addr,
7032 non_constant_p);
7033 VERIFY_CONSTANT (lhs);
7034 if (tree_int_cst_equal (lhs, bailout_value))
7035 return lhs;
7036 gcc_assert (tree_int_cst_equal (lhs, continue_value));
7037 r = cxx_eval_constant_expression (call, TREE_OPERAND (t, 1),
7038 allow_non_constant, addr, non_constant_p);
7039 VERIFY_CONSTANT (r);
7040 return r;
7041 }
7042
7043 /* REF is a COMPONENT_REF designating a particular field. V is a vector of
7044 CONSTRUCTOR elements to initialize (part of) an object containing that
7045 field. Return a pointer to the constructor_elt corresponding to the
7046 initialization of the field. */
7047
7048 static constructor_elt *
base_field_constructor_elt(VEC (constructor_elt,gc)* v,tree ref)7049 base_field_constructor_elt (VEC(constructor_elt,gc) *v, tree ref)
7050 {
7051 tree aggr = TREE_OPERAND (ref, 0);
7052 tree field = TREE_OPERAND (ref, 1);
7053 HOST_WIDE_INT i;
7054 constructor_elt *ce;
7055
7056 gcc_assert (TREE_CODE (ref) == COMPONENT_REF);
7057
7058 if (TREE_CODE (aggr) == COMPONENT_REF)
7059 {
7060 constructor_elt *base_ce
7061 = base_field_constructor_elt (v, aggr);
7062 v = CONSTRUCTOR_ELTS (base_ce->value);
7063 }
7064
7065 for (i = 0; VEC_iterate (constructor_elt, v, i, ce); ++i)
7066 if (ce->index == field)
7067 return ce;
7068
7069 gcc_unreachable ();
7070 return NULL;
7071 }
7072
7073 /* Subroutine of cxx_eval_constant_expression.
7074 The expression tree T denotes a C-style array or a C-style
7075 aggregate. Reduce it to a constant expression. */
7076
7077 static tree
cxx_eval_bare_aggregate(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)7078 cxx_eval_bare_aggregate (const constexpr_call *call, tree t,
7079 bool allow_non_constant, bool addr,
7080 bool *non_constant_p)
7081 {
7082 VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (t);
7083 VEC(constructor_elt,gc) *n = VEC_alloc (constructor_elt, gc,
7084 VEC_length (constructor_elt, v));
7085 constructor_elt *ce;
7086 HOST_WIDE_INT i;
7087 bool changed = false;
7088 gcc_assert (!BRACE_ENCLOSED_INITIALIZER_P (t));
7089 for (i = 0; VEC_iterate (constructor_elt, v, i, ce); ++i)
7090 {
7091 tree elt = cxx_eval_constant_expression (call, ce->value,
7092 allow_non_constant, addr,
7093 non_constant_p);
7094 /* Don't VERIFY_CONSTANT here. */
7095 if (allow_non_constant && *non_constant_p)
7096 goto fail;
7097 if (elt != ce->value)
7098 changed = true;
7099 if (TREE_CODE (ce->index) == COMPONENT_REF)
7100 {
7101 /* This is an initialization of a vfield inside a base
7102 subaggregate that we already initialized; push this
7103 initialization into the previous initialization. */
7104 constructor_elt *inner = base_field_constructor_elt (n, ce->index);
7105 inner->value = elt;
7106 }
7107 else if (TREE_CODE (ce->index) == NOP_EXPR)
7108 {
7109 /* This is an initializer for an empty base; now that we've
7110 checked that it's constant, we can ignore it. */
7111 gcc_assert (is_empty_class (TREE_TYPE (TREE_TYPE (ce->index))));
7112 }
7113 else
7114 CONSTRUCTOR_APPEND_ELT (n, ce->index, elt);
7115 }
7116 if (*non_constant_p || !changed)
7117 {
7118 fail:
7119 VEC_free (constructor_elt, gc, n);
7120 return t;
7121 }
7122 t = build_constructor (TREE_TYPE (t), n);
7123 TREE_CONSTANT (t) = true;
7124 return t;
7125 }
7126
7127 /* Subroutine of cxx_eval_constant_expression.
7128 The expression tree T is a VEC_INIT_EXPR which denotes the desired
7129 initialization of a non-static data member of array type. Reduce it to a
7130 CONSTRUCTOR.
7131
7132 Note that apart from value-initialization (when VALUE_INIT is true),
7133 this is only intended to support value-initialization and the
7134 initializations done by defaulted constructors for classes with
7135 non-static data members of array type. In this case, VEC_INIT_EXPR_INIT
7136 will either be NULL_TREE for the default constructor, or a COMPONENT_REF
7137 for the copy/move constructor. */
7138
7139 static tree
cxx_eval_vec_init_1(const constexpr_call * call,tree atype,tree init,bool value_init,bool allow_non_constant,bool addr,bool * non_constant_p)7140 cxx_eval_vec_init_1 (const constexpr_call *call, tree atype, tree init,
7141 bool value_init, bool allow_non_constant, bool addr,
7142 bool *non_constant_p)
7143 {
7144 tree elttype = TREE_TYPE (atype);
7145 int max = tree_low_cst (array_type_nelts (atype), 0);
7146 VEC(constructor_elt,gc) *n = VEC_alloc (constructor_elt, gc, max + 1);
7147 bool pre_init = false;
7148 int i;
7149
7150 /* For the default constructor, build up a call to the default
7151 constructor of the element type. We only need to handle class types
7152 here, as for a constructor to be constexpr, all members must be
7153 initialized, which for a defaulted default constructor means they must
7154 be of a class type with a constexpr default constructor. */
7155 if (TREE_CODE (elttype) == ARRAY_TYPE)
7156 /* We only do this at the lowest level. */;
7157 else if (value_init)
7158 {
7159 init = build_value_init (elttype, tf_warning_or_error);
7160 init = cxx_eval_constant_expression
7161 (call, init, allow_non_constant, addr, non_constant_p);
7162 pre_init = true;
7163 }
7164 else if (!init)
7165 {
7166 VEC(tree,gc) *argvec = make_tree_vector ();
7167 init = build_special_member_call (NULL_TREE, complete_ctor_identifier,
7168 &argvec, elttype, LOOKUP_NORMAL,
7169 tf_warning_or_error);
7170 release_tree_vector (argvec);
7171 init = cxx_eval_constant_expression (call, init, allow_non_constant,
7172 addr, non_constant_p);
7173 pre_init = true;
7174 }
7175
7176 if (*non_constant_p && !allow_non_constant)
7177 goto fail;
7178
7179 for (i = 0; i <= max; ++i)
7180 {
7181 tree idx = build_int_cst (size_type_node, i);
7182 tree eltinit;
7183 if (TREE_CODE (elttype) == ARRAY_TYPE)
7184 {
7185 /* A multidimensional array; recurse. */
7186 if (value_init || init == NULL_TREE)
7187 eltinit = NULL_TREE;
7188 else
7189 eltinit = cp_build_array_ref (input_location, init, idx,
7190 tf_warning_or_error);
7191 eltinit = cxx_eval_vec_init_1 (call, elttype, eltinit, value_init,
7192 allow_non_constant, addr,
7193 non_constant_p);
7194 }
7195 else if (pre_init)
7196 {
7197 /* Initializing an element using value or default initialization
7198 we just pre-built above. */
7199 if (i == 0)
7200 eltinit = init;
7201 else
7202 eltinit = unshare_expr (init);
7203 }
7204 else
7205 {
7206 /* Copying an element. */
7207 VEC(tree,gc) *argvec;
7208 gcc_assert (same_type_ignoring_top_level_qualifiers_p
7209 (atype, TREE_TYPE (init)));
7210 eltinit = cp_build_array_ref (input_location, init, idx,
7211 tf_warning_or_error);
7212 if (!real_lvalue_p (init))
7213 eltinit = move (eltinit);
7214 argvec = make_tree_vector ();
7215 VEC_quick_push (tree, argvec, eltinit);
7216 eltinit = (build_special_member_call
7217 (NULL_TREE, complete_ctor_identifier, &argvec,
7218 elttype, LOOKUP_NORMAL, tf_warning_or_error));
7219 release_tree_vector (argvec);
7220 eltinit = cxx_eval_constant_expression
7221 (call, eltinit, allow_non_constant, addr, non_constant_p);
7222 }
7223 if (*non_constant_p && !allow_non_constant)
7224 goto fail;
7225 CONSTRUCTOR_APPEND_ELT (n, idx, eltinit);
7226 }
7227
7228 if (!*non_constant_p)
7229 {
7230 init = build_constructor (atype, n);
7231 TREE_CONSTANT (init) = true;
7232 return init;
7233 }
7234
7235 fail:
7236 VEC_free (constructor_elt, gc, n);
7237 return init;
7238 }
7239
7240 static tree
cxx_eval_vec_init(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)7241 cxx_eval_vec_init (const constexpr_call *call, tree t,
7242 bool allow_non_constant, bool addr,
7243 bool *non_constant_p)
7244 {
7245 tree atype = TREE_TYPE (t);
7246 tree init = VEC_INIT_EXPR_INIT (t);
7247 tree r = cxx_eval_vec_init_1 (call, atype, init,
7248 VEC_INIT_EXPR_VALUE_INIT (t),
7249 allow_non_constant, addr, non_constant_p);
7250 if (*non_constant_p)
7251 return t;
7252 else
7253 return r;
7254 }
7255
7256 /* A less strict version of fold_indirect_ref_1, which requires cv-quals to
7257 match. We want to be less strict for simple *& folding; if we have a
7258 non-const temporary that we access through a const pointer, that should
7259 work. We handle this here rather than change fold_indirect_ref_1
7260 because we're dealing with things like ADDR_EXPR of INTEGER_CST which
7261 don't really make sense outside of constant expression evaluation. Also
7262 we want to allow folding to COMPONENT_REF, which could cause trouble
7263 with TBAA in fold_indirect_ref_1.
7264
7265 Try to keep this function synced with fold_indirect_ref_1. */
7266
7267 static tree
cxx_fold_indirect_ref(location_t loc,tree type,tree op0,bool * empty_base)7268 cxx_fold_indirect_ref (location_t loc, tree type, tree op0, bool *empty_base)
7269 {
7270 tree sub, subtype;
7271
7272 sub = op0;
7273 STRIP_NOPS (sub);
7274 subtype = TREE_TYPE (sub);
7275 if (!POINTER_TYPE_P (subtype))
7276 return NULL_TREE;
7277
7278 if (TREE_CODE (sub) == ADDR_EXPR)
7279 {
7280 tree op = TREE_OPERAND (sub, 0);
7281 tree optype = TREE_TYPE (op);
7282
7283 /* *&CONST_DECL -> to the value of the const decl. */
7284 if (TREE_CODE (op) == CONST_DECL)
7285 return DECL_INITIAL (op);
7286 /* *&p => p; make sure to handle *&"str"[cst] here. */
7287 if (same_type_ignoring_top_level_qualifiers_p (optype, type))
7288 {
7289 tree fop = fold_read_from_constant_string (op);
7290 if (fop)
7291 return fop;
7292 else
7293 return op;
7294 }
7295 /* *(foo *)&fooarray => fooarray[0] */
7296 else if (TREE_CODE (optype) == ARRAY_TYPE
7297 && (same_type_ignoring_top_level_qualifiers_p
7298 (type, TREE_TYPE (optype))))
7299 {
7300 tree type_domain = TYPE_DOMAIN (optype);
7301 tree min_val = size_zero_node;
7302 if (type_domain && TYPE_MIN_VALUE (type_domain))
7303 min_val = TYPE_MIN_VALUE (type_domain);
7304 return build4_loc (loc, ARRAY_REF, type, op, min_val,
7305 NULL_TREE, NULL_TREE);
7306 }
7307 /* *(foo *)&complexfoo => __real__ complexfoo */
7308 else if (TREE_CODE (optype) == COMPLEX_TYPE
7309 && (same_type_ignoring_top_level_qualifiers_p
7310 (type, TREE_TYPE (optype))))
7311 return fold_build1_loc (loc, REALPART_EXPR, type, op);
7312 /* *(foo *)&vectorfoo => BIT_FIELD_REF<vectorfoo,...> */
7313 else if (TREE_CODE (optype) == VECTOR_TYPE
7314 && (same_type_ignoring_top_level_qualifiers_p
7315 (type, TREE_TYPE (optype))))
7316 {
7317 tree part_width = TYPE_SIZE (type);
7318 tree index = bitsize_int (0);
7319 return fold_build3_loc (loc, BIT_FIELD_REF, type, op, part_width, index);
7320 }
7321 /* Also handle conversion to an empty base class, which
7322 is represented with a NOP_EXPR. */
7323 else if (is_empty_class (type)
7324 && CLASS_TYPE_P (optype)
7325 && DERIVED_FROM_P (type, optype))
7326 {
7327 *empty_base = true;
7328 return op;
7329 }
7330 /* *(foo *)&struct_with_foo_field => COMPONENT_REF */
7331 else if (RECORD_OR_UNION_TYPE_P (optype))
7332 {
7333 tree field = TYPE_FIELDS (optype);
7334 for (; field; field = DECL_CHAIN (field))
7335 if (TREE_CODE (field) == FIELD_DECL
7336 && integer_zerop (byte_position (field))
7337 && (same_type_ignoring_top_level_qualifiers_p
7338 (TREE_TYPE (field), type)))
7339 {
7340 return fold_build3 (COMPONENT_REF, type, op, field, NULL_TREE);
7341 break;
7342 }
7343 }
7344 }
7345 else if (TREE_CODE (sub) == POINTER_PLUS_EXPR
7346 && TREE_CODE (TREE_OPERAND (sub, 1)) == INTEGER_CST)
7347 {
7348 tree op00 = TREE_OPERAND (sub, 0);
7349 tree op01 = TREE_OPERAND (sub, 1);
7350
7351 STRIP_NOPS (op00);
7352 if (TREE_CODE (op00) == ADDR_EXPR)
7353 {
7354 tree op00type;
7355 op00 = TREE_OPERAND (op00, 0);
7356 op00type = TREE_TYPE (op00);
7357
7358 /* ((foo*)&vectorfoo)[1] => BIT_FIELD_REF<vectorfoo,...> */
7359 if (TREE_CODE (op00type) == VECTOR_TYPE
7360 && (same_type_ignoring_top_level_qualifiers_p
7361 (type, TREE_TYPE (op00type))))
7362 {
7363 HOST_WIDE_INT offset = tree_low_cst (op01, 0);
7364 tree part_width = TYPE_SIZE (type);
7365 unsigned HOST_WIDE_INT part_widthi = tree_low_cst (part_width, 0)/BITS_PER_UNIT;
7366 unsigned HOST_WIDE_INT indexi = offset * BITS_PER_UNIT;
7367 tree index = bitsize_int (indexi);
7368
7369 if (offset/part_widthi <= TYPE_VECTOR_SUBPARTS (op00type))
7370 return fold_build3_loc (loc,
7371 BIT_FIELD_REF, type, op00,
7372 part_width, index);
7373
7374 }
7375 /* ((foo*)&complexfoo)[1] => __imag__ complexfoo */
7376 else if (TREE_CODE (op00type) == COMPLEX_TYPE
7377 && (same_type_ignoring_top_level_qualifiers_p
7378 (type, TREE_TYPE (op00type))))
7379 {
7380 tree size = TYPE_SIZE_UNIT (type);
7381 if (tree_int_cst_equal (size, op01))
7382 return fold_build1_loc (loc, IMAGPART_EXPR, type, op00);
7383 }
7384 /* ((foo *)&fooarray)[1] => fooarray[1] */
7385 else if (TREE_CODE (op00type) == ARRAY_TYPE
7386 && (same_type_ignoring_top_level_qualifiers_p
7387 (type, TREE_TYPE (op00type))))
7388 {
7389 tree type_domain = TYPE_DOMAIN (op00type);
7390 tree min_val = size_zero_node;
7391 if (type_domain && TYPE_MIN_VALUE (type_domain))
7392 min_val = TYPE_MIN_VALUE (type_domain);
7393 op01 = size_binop_loc (loc, EXACT_DIV_EXPR, op01,
7394 TYPE_SIZE_UNIT (type));
7395 op01 = size_binop_loc (loc, PLUS_EXPR, op01, min_val);
7396 return build4_loc (loc, ARRAY_REF, type, op00, op01,
7397 NULL_TREE, NULL_TREE);
7398 }
7399 /* ((foo *)&struct_with_foo_field)[1] => COMPONENT_REF */
7400 else if (RECORD_OR_UNION_TYPE_P (op00type))
7401 {
7402 tree field = TYPE_FIELDS (op00type);
7403 for (; field; field = DECL_CHAIN (field))
7404 if (TREE_CODE (field) == FIELD_DECL
7405 && tree_int_cst_equal (byte_position (field), op01)
7406 && (same_type_ignoring_top_level_qualifiers_p
7407 (TREE_TYPE (field), type)))
7408 {
7409 return fold_build3 (COMPONENT_REF, type, op00,
7410 field, NULL_TREE);
7411 break;
7412 }
7413 }
7414 }
7415 }
7416 /* *(foo *)fooarrptr => (*fooarrptr)[0] */
7417 else if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE
7418 && (same_type_ignoring_top_level_qualifiers_p
7419 (type, TREE_TYPE (TREE_TYPE (subtype)))))
7420 {
7421 tree type_domain;
7422 tree min_val = size_zero_node;
7423 tree newsub = cxx_fold_indirect_ref (loc, TREE_TYPE (subtype), sub, NULL);
7424 if (newsub)
7425 sub = newsub;
7426 else
7427 sub = build1_loc (loc, INDIRECT_REF, TREE_TYPE (subtype), sub);
7428 type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
7429 if (type_domain && TYPE_MIN_VALUE (type_domain))
7430 min_val = TYPE_MIN_VALUE (type_domain);
7431 return build4_loc (loc, ARRAY_REF, type, sub, min_val, NULL_TREE,
7432 NULL_TREE);
7433 }
7434
7435 return NULL_TREE;
7436 }
7437
7438 static tree
cxx_eval_indirect_ref(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)7439 cxx_eval_indirect_ref (const constexpr_call *call, tree t,
7440 bool allow_non_constant, bool addr,
7441 bool *non_constant_p)
7442 {
7443 tree orig_op0 = TREE_OPERAND (t, 0);
7444 tree op0 = cxx_eval_constant_expression (call, orig_op0, allow_non_constant,
7445 /*addr*/false, non_constant_p);
7446 bool empty_base = false;
7447 tree r;
7448
7449 /* Don't VERIFY_CONSTANT here. */
7450 if (*non_constant_p)
7451 return t;
7452
7453 r = cxx_fold_indirect_ref (EXPR_LOCATION (t), TREE_TYPE (t), op0,
7454 &empty_base);
7455
7456 if (r)
7457 r = cxx_eval_constant_expression (call, r, allow_non_constant,
7458 addr, non_constant_p);
7459 else
7460 {
7461 tree sub = op0;
7462 STRIP_NOPS (sub);
7463 if (TREE_CODE (sub) == ADDR_EXPR)
7464 {
7465 /* We couldn't fold to a constant value. Make sure it's not
7466 something we should have been able to fold. */
7467 gcc_assert (!same_type_ignoring_top_level_qualifiers_p
7468 (TREE_TYPE (TREE_TYPE (sub)), TREE_TYPE (t)));
7469 /* DR 1188 says we don't have to deal with this. */
7470 if (!allow_non_constant)
7471 error ("accessing value of %qE through a %qT glvalue in a "
7472 "constant expression", build_fold_indirect_ref (sub),
7473 TREE_TYPE (t));
7474 *non_constant_p = true;
7475 return t;
7476 }
7477 }
7478
7479 /* If we're pulling out the value of an empty base, make sure
7480 that the whole object is constant and then return an empty
7481 CONSTRUCTOR. */
7482 if (empty_base)
7483 {
7484 VERIFY_CONSTANT (r);
7485 r = build_constructor (TREE_TYPE (t), NULL);
7486 TREE_CONSTANT (r) = true;
7487 }
7488
7489 if (r == NULL_TREE)
7490 {
7491 if (!addr)
7492 VERIFY_CONSTANT (t);
7493 return t;
7494 }
7495 return r;
7496 }
7497
7498 /* Complain about R, a VAR_DECL, not being usable in a constant expression.
7499 Shared between potential_constant_expression and
7500 cxx_eval_constant_expression. */
7501
7502 static void
non_const_var_error(tree r)7503 non_const_var_error (tree r)
7504 {
7505 tree type = TREE_TYPE (r);
7506 error ("the value of %qD is not usable in a constant "
7507 "expression", r);
7508 /* Avoid error cascade. */
7509 if (DECL_INITIAL (r) == error_mark_node)
7510 return;
7511 if (DECL_DECLARED_CONSTEXPR_P (r))
7512 inform (DECL_SOURCE_LOCATION (r),
7513 "%qD used in its own initializer", r);
7514 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
7515 {
7516 if (!CP_TYPE_CONST_P (type))
7517 inform (DECL_SOURCE_LOCATION (r),
7518 "%q#D is not const", r);
7519 else if (CP_TYPE_VOLATILE_P (type))
7520 inform (DECL_SOURCE_LOCATION (r),
7521 "%q#D is volatile", r);
7522 else if (!DECL_INITIAL (r)
7523 || !TREE_CONSTANT (DECL_INITIAL (r)))
7524 inform (DECL_SOURCE_LOCATION (r),
7525 "%qD was not initialized with a constant "
7526 "expression", r);
7527 else
7528 gcc_unreachable ();
7529 }
7530 else
7531 {
7532 if (cxx_dialect >= cxx0x && !DECL_DECLARED_CONSTEXPR_P (r))
7533 inform (DECL_SOURCE_LOCATION (r),
7534 "%qD was not declared %<constexpr%>", r);
7535 else
7536 inform (DECL_SOURCE_LOCATION (r),
7537 "%qD does not have integral or enumeration type",
7538 r);
7539 }
7540 }
7541
7542 /* Attempt to reduce the expression T to a constant value.
7543 On failure, issue diagnostic and return error_mark_node. */
7544 /* FIXME unify with c_fully_fold */
7545
7546 static tree
cxx_eval_constant_expression(const constexpr_call * call,tree t,bool allow_non_constant,bool addr,bool * non_constant_p)7547 cxx_eval_constant_expression (const constexpr_call *call, tree t,
7548 bool allow_non_constant, bool addr,
7549 bool *non_constant_p)
7550 {
7551 tree r = t;
7552
7553 if (t == error_mark_node)
7554 {
7555 *non_constant_p = true;
7556 return t;
7557 }
7558 if (CONSTANT_CLASS_P (t))
7559 {
7560 if (TREE_CODE (t) == PTRMEM_CST)
7561 t = cplus_expand_constant (t);
7562 return t;
7563 }
7564 if (TREE_CODE (t) != NOP_EXPR
7565 && reduced_constant_expression_p (t))
7566 return fold (t);
7567
7568 switch (TREE_CODE (t))
7569 {
7570 case VAR_DECL:
7571 if (addr)
7572 return t;
7573 /* else fall through. */
7574 case CONST_DECL:
7575 r = integral_constant_value (t);
7576 if (TREE_CODE (r) == TARGET_EXPR
7577 && TREE_CODE (TARGET_EXPR_INITIAL (r)) == CONSTRUCTOR)
7578 r = TARGET_EXPR_INITIAL (r);
7579 if (DECL_P (r))
7580 {
7581 if (!allow_non_constant)
7582 non_const_var_error (r);
7583 *non_constant_p = true;
7584 }
7585 break;
7586
7587 case FUNCTION_DECL:
7588 case TEMPLATE_DECL:
7589 case LABEL_DECL:
7590 return t;
7591
7592 case PARM_DECL:
7593 if (call && DECL_CONTEXT (t) == call->fundef->decl)
7594 {
7595 if (DECL_ARTIFICIAL (t) && DECL_CONSTRUCTOR_P (DECL_CONTEXT (t)))
7596 {
7597 if (!allow_non_constant)
7598 sorry ("use of the value of the object being constructed "
7599 "in a constant expression");
7600 *non_constant_p = true;
7601 }
7602 else
7603 r = lookup_parameter_binding (call, t);
7604 }
7605 else if (addr)
7606 /* Defer in case this is only used for its type. */;
7607 else
7608 {
7609 if (!allow_non_constant)
7610 error ("%qE is not a constant expression", t);
7611 *non_constant_p = true;
7612 }
7613 break;
7614
7615 case CALL_EXPR:
7616 case AGGR_INIT_EXPR:
7617 r = cxx_eval_call_expression (call, t, allow_non_constant, addr,
7618 non_constant_p);
7619 break;
7620
7621 case TARGET_EXPR:
7622 if (!literal_type_p (TREE_TYPE (t)))
7623 {
7624 if (!allow_non_constant)
7625 {
7626 error ("temporary of non-literal type %qT in a "
7627 "constant expression", TREE_TYPE (t));
7628 explain_non_literal_class (TREE_TYPE (t));
7629 }
7630 *non_constant_p = true;
7631 break;
7632 }
7633 /* else fall through. */
7634 case INIT_EXPR:
7635 /* Pass false for 'addr' because these codes indicate
7636 initialization of a temporary. */
7637 r = cxx_eval_constant_expression (call, TREE_OPERAND (t, 1),
7638 allow_non_constant, false,
7639 non_constant_p);
7640 if (!*non_constant_p)
7641 /* Adjust the type of the result to the type of the temporary. */
7642 r = adjust_temp_type (TREE_TYPE (t), r);
7643 break;
7644
7645 case SCOPE_REF:
7646 r = cxx_eval_constant_expression (call, TREE_OPERAND (t, 1),
7647 allow_non_constant, addr,
7648 non_constant_p);
7649 break;
7650
7651 case RETURN_EXPR:
7652 case NON_LVALUE_EXPR:
7653 case TRY_CATCH_EXPR:
7654 case CLEANUP_POINT_EXPR:
7655 case MUST_NOT_THROW_EXPR:
7656 case SAVE_EXPR:
7657 r = cxx_eval_constant_expression (call, TREE_OPERAND (t, 0),
7658 allow_non_constant, addr,
7659 non_constant_p);
7660 break;
7661
7662 /* These differ from cxx_eval_unary_expression in that this doesn't
7663 check for a constant operand or result; an address can be
7664 constant without its operand being, and vice versa. */
7665 case INDIRECT_REF:
7666 r = cxx_eval_indirect_ref (call, t, allow_non_constant, addr,
7667 non_constant_p);
7668 break;
7669
7670 case ADDR_EXPR:
7671 {
7672 tree oldop = TREE_OPERAND (t, 0);
7673 tree op = cxx_eval_constant_expression (call, oldop,
7674 allow_non_constant,
7675 /*addr*/true,
7676 non_constant_p);
7677 /* Don't VERIFY_CONSTANT here. */
7678 if (*non_constant_p)
7679 return t;
7680 /* This function does more aggressive folding than fold itself. */
7681 r = build_fold_addr_expr_with_type (op, TREE_TYPE (t));
7682 if (TREE_CODE (r) == ADDR_EXPR && TREE_OPERAND (r, 0) == oldop)
7683 return t;
7684 break;
7685 }
7686
7687 case REALPART_EXPR:
7688 case IMAGPART_EXPR:
7689 case CONJ_EXPR:
7690 case FIX_TRUNC_EXPR:
7691 case FLOAT_EXPR:
7692 case NEGATE_EXPR:
7693 case ABS_EXPR:
7694 case BIT_NOT_EXPR:
7695 case TRUTH_NOT_EXPR:
7696 case FIXED_CONVERT_EXPR:
7697 r = cxx_eval_unary_expression (call, t, allow_non_constant, addr,
7698 non_constant_p);
7699 break;
7700
7701 case COMPOUND_EXPR:
7702 {
7703 /* check_return_expr sometimes wraps a TARGET_EXPR in a
7704 COMPOUND_EXPR; don't get confused. Also handle EMPTY_CLASS_EXPR
7705 introduced by build_call_a. */
7706 tree op0 = TREE_OPERAND (t, 0);
7707 tree op1 = TREE_OPERAND (t, 1);
7708 STRIP_NOPS (op1);
7709 if ((TREE_CODE (op0) == TARGET_EXPR && op1 == TARGET_EXPR_SLOT (op0))
7710 || TREE_CODE (op1) == EMPTY_CLASS_EXPR)
7711 r = cxx_eval_constant_expression (call, op0, allow_non_constant,
7712 addr, non_constant_p);
7713 else
7714 {
7715 /* Check that the LHS is constant and then discard it. */
7716 cxx_eval_constant_expression (call, op0, allow_non_constant,
7717 false, non_constant_p);
7718 op1 = TREE_OPERAND (t, 1);
7719 r = cxx_eval_constant_expression (call, op1, allow_non_constant,
7720 addr, non_constant_p);
7721 }
7722 }
7723 break;
7724
7725 case POINTER_PLUS_EXPR:
7726 case PLUS_EXPR:
7727 case MINUS_EXPR:
7728 case MULT_EXPR:
7729 case TRUNC_DIV_EXPR:
7730 case CEIL_DIV_EXPR:
7731 case FLOOR_DIV_EXPR:
7732 case ROUND_DIV_EXPR:
7733 case TRUNC_MOD_EXPR:
7734 case CEIL_MOD_EXPR:
7735 case ROUND_MOD_EXPR:
7736 case RDIV_EXPR:
7737 case EXACT_DIV_EXPR:
7738 case MIN_EXPR:
7739 case MAX_EXPR:
7740 case LSHIFT_EXPR:
7741 case RSHIFT_EXPR:
7742 case LROTATE_EXPR:
7743 case RROTATE_EXPR:
7744 case BIT_IOR_EXPR:
7745 case BIT_XOR_EXPR:
7746 case BIT_AND_EXPR:
7747 case TRUTH_XOR_EXPR:
7748 case LT_EXPR:
7749 case LE_EXPR:
7750 case GT_EXPR:
7751 case GE_EXPR:
7752 case EQ_EXPR:
7753 case NE_EXPR:
7754 case UNORDERED_EXPR:
7755 case ORDERED_EXPR:
7756 case UNLT_EXPR:
7757 case UNLE_EXPR:
7758 case UNGT_EXPR:
7759 case UNGE_EXPR:
7760 case UNEQ_EXPR:
7761 case RANGE_EXPR:
7762 case COMPLEX_EXPR:
7763 r = cxx_eval_binary_expression (call, t, allow_non_constant, addr,
7764 non_constant_p);
7765 break;
7766
7767 /* fold can introduce non-IF versions of these; still treat them as
7768 short-circuiting. */
7769 case TRUTH_AND_EXPR:
7770 case TRUTH_ANDIF_EXPR:
7771 r = cxx_eval_logical_expression (call, t, boolean_false_node,
7772 boolean_true_node,
7773 allow_non_constant, addr,
7774 non_constant_p);
7775 break;
7776
7777 case TRUTH_OR_EXPR:
7778 case TRUTH_ORIF_EXPR:
7779 r = cxx_eval_logical_expression (call, t, boolean_true_node,
7780 boolean_false_node,
7781 allow_non_constant, addr,
7782 non_constant_p);
7783 break;
7784
7785 case ARRAY_REF:
7786 r = cxx_eval_array_reference (call, t, allow_non_constant, addr,
7787 non_constant_p);
7788 break;
7789
7790 case COMPONENT_REF:
7791 r = cxx_eval_component_reference (call, t, allow_non_constant, addr,
7792 non_constant_p);
7793 break;
7794
7795 case BIT_FIELD_REF:
7796 r = cxx_eval_bit_field_ref (call, t, allow_non_constant, addr,
7797 non_constant_p);
7798 break;
7799
7800 case COND_EXPR:
7801 case VEC_COND_EXPR:
7802 r = cxx_eval_conditional_expression (call, t, allow_non_constant, addr,
7803 non_constant_p);
7804 break;
7805
7806 case CONSTRUCTOR:
7807 r = cxx_eval_bare_aggregate (call, t, allow_non_constant, addr,
7808 non_constant_p);
7809 break;
7810
7811 case VEC_INIT_EXPR:
7812 /* We can get this in a defaulted constructor for a class with a
7813 non-static data member of array type. Either the initializer will
7814 be NULL, meaning default-initialization, or it will be an lvalue
7815 or xvalue of the same type, meaning direct-initialization from the
7816 corresponding member. */
7817 r = cxx_eval_vec_init (call, t, allow_non_constant, addr,
7818 non_constant_p);
7819 break;
7820
7821 case CONVERT_EXPR:
7822 case VIEW_CONVERT_EXPR:
7823 case NOP_EXPR:
7824 {
7825 tree oldop = TREE_OPERAND (t, 0);
7826 tree op = oldop;
7827 tree to = TREE_TYPE (t);
7828 op = cxx_eval_constant_expression (call, TREE_OPERAND (t, 0),
7829 allow_non_constant, addr,
7830 non_constant_p);
7831 if (*non_constant_p)
7832 return t;
7833 if (op == oldop)
7834 /* We didn't fold at the top so we could check for ptr-int
7835 conversion. */
7836 return fold (t);
7837 r = fold_build1 (TREE_CODE (t), to, op);
7838 /* Conversion of an out-of-range value has implementation-defined
7839 behavior; the language considers it different from arithmetic
7840 overflow, which is undefined. */
7841 if (TREE_OVERFLOW_P (r) && !TREE_OVERFLOW_P (op))
7842 TREE_OVERFLOW (r) = false;
7843 }
7844 break;
7845
7846 case EMPTY_CLASS_EXPR:
7847 /* This is good enough for a function argument that might not get
7848 used, and they can't do anything with it, so just return it. */
7849 return t;
7850
7851 case LAMBDA_EXPR:
7852 case PREINCREMENT_EXPR:
7853 case POSTINCREMENT_EXPR:
7854 case PREDECREMENT_EXPR:
7855 case POSTDECREMENT_EXPR:
7856 case NEW_EXPR:
7857 case VEC_NEW_EXPR:
7858 case DELETE_EXPR:
7859 case VEC_DELETE_EXPR:
7860 case THROW_EXPR:
7861 case MODIFY_EXPR:
7862 case MODOP_EXPR:
7863 /* GCC internal stuff. */
7864 case VA_ARG_EXPR:
7865 case OBJ_TYPE_REF:
7866 case WITH_CLEANUP_EXPR:
7867 case STATEMENT_LIST:
7868 case BIND_EXPR:
7869 case NON_DEPENDENT_EXPR:
7870 case BASELINK:
7871 case EXPR_STMT:
7872 case OFFSET_REF:
7873 if (!allow_non_constant)
7874 error_at (EXPR_LOC_OR_HERE (t),
7875 "expression %qE is not a constant-expression", t);
7876 *non_constant_p = true;
7877 break;
7878
7879 default:
7880 internal_error ("unexpected expression %qE of kind %s", t,
7881 tree_code_name[TREE_CODE (t)]);
7882 *non_constant_p = true;
7883 break;
7884 }
7885
7886 if (r == error_mark_node)
7887 *non_constant_p = true;
7888
7889 if (*non_constant_p)
7890 return t;
7891 else
7892 return r;
7893 }
7894
7895 static tree
cxx_eval_outermost_constant_expr(tree t,bool allow_non_constant)7896 cxx_eval_outermost_constant_expr (tree t, bool allow_non_constant)
7897 {
7898 bool non_constant_p = false;
7899 tree r = cxx_eval_constant_expression (NULL, t, allow_non_constant,
7900 false, &non_constant_p);
7901
7902 verify_constant (r, allow_non_constant, &non_constant_p);
7903
7904 if (TREE_CODE (t) != CONSTRUCTOR
7905 && cp_has_mutable_p (TREE_TYPE (t)))
7906 {
7907 /* We allow a mutable type if the original expression was a
7908 CONSTRUCTOR so that we can do aggregate initialization of
7909 constexpr variables. */
7910 if (!allow_non_constant)
7911 error ("%qT cannot be the type of a complete constant expression "
7912 "because it has mutable sub-objects", TREE_TYPE (t));
7913 non_constant_p = true;
7914 }
7915
7916 /* Technically we should check this for all subexpressions, but that
7917 runs into problems with our internal representation of pointer
7918 subtraction and the 5.19 rules are still in flux. */
7919 if (CONVERT_EXPR_CODE_P (TREE_CODE (r))
7920 && ARITHMETIC_TYPE_P (TREE_TYPE (r))
7921 && TREE_CODE (TREE_OPERAND (r, 0)) == ADDR_EXPR)
7922 {
7923 if (!allow_non_constant)
7924 error ("conversion from pointer type %qT "
7925 "to arithmetic type %qT in a constant-expression",
7926 TREE_TYPE (TREE_OPERAND (r, 0)), TREE_TYPE (r));
7927 non_constant_p = true;
7928 }
7929
7930 if (non_constant_p && !allow_non_constant)
7931 return error_mark_node;
7932 else if (non_constant_p && TREE_CONSTANT (t))
7933 {
7934 /* This isn't actually constant, so unset TREE_CONSTANT. */
7935 if (EXPR_P (t) || TREE_CODE (t) == CONSTRUCTOR)
7936 r = copy_node (t);
7937 else
7938 r = build_nop (TREE_TYPE (t), t);
7939 TREE_CONSTANT (r) = false;
7940 return r;
7941 }
7942 else if (non_constant_p || r == t)
7943 return t;
7944 else if (TREE_CODE (r) == CONSTRUCTOR && CLASS_TYPE_P (TREE_TYPE (r)))
7945 {
7946 if (TREE_CODE (t) == TARGET_EXPR
7947 && TARGET_EXPR_INITIAL (t) == r)
7948 return t;
7949 else
7950 {
7951 r = get_target_expr (r);
7952 TREE_CONSTANT (r) = true;
7953 return r;
7954 }
7955 }
7956 else
7957 return r;
7958 }
7959
7960 /* Returns true if T is a valid subexpression of a constant expression,
7961 even if it isn't itself a constant expression. */
7962
7963 bool
is_sub_constant_expr(tree t)7964 is_sub_constant_expr (tree t)
7965 {
7966 bool non_constant_p = false;
7967 cxx_eval_constant_expression (NULL, t, true, false, &non_constant_p);
7968 return !non_constant_p;
7969 }
7970
7971 /* If T represents a constant expression returns its reduced value.
7972 Otherwise return error_mark_node. If T is dependent, then
7973 return NULL. */
7974
7975 tree
cxx_constant_value(tree t)7976 cxx_constant_value (tree t)
7977 {
7978 return cxx_eval_outermost_constant_expr (t, false);
7979 }
7980
7981 /* If T is a constant expression, returns its reduced value.
7982 Otherwise, if T does not have TREE_CONSTANT set, returns T.
7983 Otherwise, returns a version of T without TREE_CONSTANT. */
7984
7985 tree
maybe_constant_value(tree t)7986 maybe_constant_value (tree t)
7987 {
7988 tree r;
7989
7990 if (type_dependent_expression_p (t)
7991 || type_unknown_p (t)
7992 || BRACE_ENCLOSED_INITIALIZER_P (t)
7993 || !potential_constant_expression (t)
7994 || value_dependent_expression_p (t))
7995 {
7996 if (TREE_OVERFLOW_P (t))
7997 {
7998 t = build_nop (TREE_TYPE (t), t);
7999 TREE_CONSTANT (t) = false;
8000 }
8001 return t;
8002 }
8003
8004 r = cxx_eval_outermost_constant_expr (t, true);
8005 #ifdef ENABLE_CHECKING
8006 /* cp_tree_equal looks through NOPs, so allow them. */
8007 gcc_assert (r == t
8008 || CONVERT_EXPR_P (t)
8009 || (TREE_CONSTANT (t) && !TREE_CONSTANT (r))
8010 || !cp_tree_equal (r, t));
8011 #endif
8012 return r;
8013 }
8014
8015 /* Like maybe_constant_value, but returns a CONSTRUCTOR directly, rather
8016 than wrapped in a TARGET_EXPR. */
8017
8018 tree
maybe_constant_init(tree t)8019 maybe_constant_init (tree t)
8020 {
8021 t = maybe_constant_value (t);
8022 if (TREE_CODE (t) == TARGET_EXPR)
8023 {
8024 tree init = TARGET_EXPR_INITIAL (t);
8025 if (TREE_CODE (init) == CONSTRUCTOR
8026 && TREE_CONSTANT (init))
8027 t = init;
8028 }
8029 return t;
8030 }
8031
8032 #if 0
8033 /* FIXME see ADDR_EXPR section in potential_constant_expression_1. */
8034 /* Return true if the object referred to by REF has automatic or thread
8035 local storage. */
8036
8037 enum { ck_ok, ck_bad, ck_unknown };
8038 static int
8039 check_automatic_or_tls (tree ref)
8040 {
8041 enum machine_mode mode;
8042 HOST_WIDE_INT bitsize, bitpos;
8043 tree offset;
8044 int volatilep = 0, unsignedp = 0;
8045 tree decl = get_inner_reference (ref, &bitsize, &bitpos, &offset,
8046 &mode, &unsignedp, &volatilep, false);
8047 duration_kind dk;
8048
8049 /* If there isn't a decl in the middle, we don't know the linkage here,
8050 and this isn't a constant expression anyway. */
8051 if (!DECL_P (decl))
8052 return ck_unknown;
8053 dk = decl_storage_duration (decl);
8054 return (dk == dk_auto || dk == dk_thread) ? ck_bad : ck_ok;
8055 }
8056 #endif
8057
8058 /* Return true if T denotes a potentially constant expression. Issue
8059 diagnostic as appropriate under control of FLAGS. If WANT_RVAL is true,
8060 an lvalue-rvalue conversion is implied.
8061
8062 C++0x [expr.const] used to say
8063
8064 6 An expression is a potential constant expression if it is
8065 a constant expression where all occurences of function
8066 parameters are replaced by arbitrary constant expressions
8067 of the appropriate type.
8068
8069 2 A conditional expression is a constant expression unless it
8070 involves one of the following as a potentially evaluated
8071 subexpression (3.2), but subexpressions of logical AND (5.14),
8072 logical OR (5.15), and conditional (5.16) operations that are
8073 not evaluated are not considered. */
8074
8075 static bool
potential_constant_expression_1(tree t,bool want_rval,tsubst_flags_t flags)8076 potential_constant_expression_1 (tree t, bool want_rval, tsubst_flags_t flags)
8077 {
8078 enum { any = false, rval = true };
8079 int i;
8080 tree tmp;
8081
8082 /* C++98 has different rules for the form of a constant expression that
8083 are enforced in the parser, so we can assume that anything that gets
8084 this far is suitable. */
8085 if (cxx_dialect < cxx0x)
8086 return true;
8087
8088 if (t == error_mark_node)
8089 return false;
8090 if (t == NULL_TREE)
8091 return true;
8092 if (TREE_THIS_VOLATILE (t))
8093 {
8094 if (flags & tf_error)
8095 error ("expression %qE has side-effects", t);
8096 return false;
8097 }
8098 if (CONSTANT_CLASS_P (t))
8099 {
8100 if (TREE_OVERFLOW (t))
8101 {
8102 if (flags & tf_error)
8103 {
8104 permerror (EXPR_LOC_OR_HERE (t),
8105 "overflow in constant expression");
8106 if (flag_permissive)
8107 return true;
8108 }
8109 return false;
8110 }
8111 return true;
8112 }
8113
8114 switch (TREE_CODE (t))
8115 {
8116 case FUNCTION_DECL:
8117 case BASELINK:
8118 case TEMPLATE_DECL:
8119 case OVERLOAD:
8120 case TEMPLATE_ID_EXPR:
8121 case LABEL_DECL:
8122 case CONST_DECL:
8123 case SIZEOF_EXPR:
8124 case ALIGNOF_EXPR:
8125 case OFFSETOF_EXPR:
8126 case NOEXCEPT_EXPR:
8127 case TEMPLATE_PARM_INDEX:
8128 case TRAIT_EXPR:
8129 case IDENTIFIER_NODE:
8130 case USERDEF_LITERAL:
8131 /* We can see a FIELD_DECL in a pointer-to-member expression. */
8132 case FIELD_DECL:
8133 case PARM_DECL:
8134 case USING_DECL:
8135 return true;
8136
8137 case AGGR_INIT_EXPR:
8138 case CALL_EXPR:
8139 /* -- an invocation of a function other than a constexpr function
8140 or a constexpr constructor. */
8141 {
8142 tree fun = get_function_named_in_call (t);
8143 const int nargs = call_expr_nargs (t);
8144 i = 0;
8145
8146 if (is_overloaded_fn (fun))
8147 {
8148 if (TREE_CODE (fun) == FUNCTION_DECL)
8149 {
8150 if (builtin_valid_in_constant_expr_p (fun))
8151 return true;
8152 if (!DECL_DECLARED_CONSTEXPR_P (fun)
8153 /* Allow any built-in function; if the expansion
8154 isn't constant, we'll deal with that then. */
8155 && !is_builtin_fn (fun))
8156 {
8157 if (flags & tf_error)
8158 {
8159 error_at (EXPR_LOC_OR_HERE (t),
8160 "call to non-constexpr function %qD", fun);
8161 explain_invalid_constexpr_fn (fun);
8162 }
8163 return false;
8164 }
8165 /* A call to a non-static member function takes the address
8166 of the object as the first argument. But in a constant
8167 expression the address will be folded away, so look
8168 through it now. */
8169 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fun)
8170 && !DECL_CONSTRUCTOR_P (fun))
8171 {
8172 tree x = get_nth_callarg (t, 0);
8173 if (is_this_parameter (x))
8174 {
8175 if (DECL_CONSTRUCTOR_P (DECL_CONTEXT (x)))
8176 {
8177 if (flags & tf_error)
8178 sorry ("calling a member function of the "
8179 "object being constructed in a constant "
8180 "expression");
8181 return false;
8182 }
8183 /* Otherwise OK. */;
8184 }
8185 else if (!potential_constant_expression_1 (x, rval, flags))
8186 return false;
8187 i = 1;
8188 }
8189 }
8190 else
8191 fun = get_first_fn (fun);
8192 /* Skip initial arguments to base constructors. */
8193 if (DECL_BASE_CONSTRUCTOR_P (fun))
8194 i = num_artificial_parms_for (fun);
8195 fun = DECL_ORIGIN (fun);
8196 }
8197 else
8198 {
8199 if (potential_constant_expression_1 (fun, rval, flags))
8200 /* Might end up being a constant function pointer. */;
8201 else
8202 return false;
8203 }
8204 for (; i < nargs; ++i)
8205 {
8206 tree x = get_nth_callarg (t, i);
8207 if (!potential_constant_expression_1 (x, rval, flags))
8208 return false;
8209 }
8210 return true;
8211 }
8212
8213 case NON_LVALUE_EXPR:
8214 /* -- an lvalue-to-rvalue conversion (4.1) unless it is applied to
8215 -- an lvalue of integral type that refers to a non-volatile
8216 const variable or static data member initialized with
8217 constant expressions, or
8218
8219 -- an lvalue of literal type that refers to non-volatile
8220 object defined with constexpr, or that refers to a
8221 sub-object of such an object; */
8222 return potential_constant_expression_1 (TREE_OPERAND (t, 0), rval, flags);
8223
8224 case VAR_DECL:
8225 if (want_rval && !decl_constant_var_p (t)
8226 && !dependent_type_p (TREE_TYPE (t)))
8227 {
8228 if (flags & tf_error)
8229 non_const_var_error (t);
8230 return false;
8231 }
8232 return true;
8233
8234 case NOP_EXPR:
8235 case CONVERT_EXPR:
8236 case VIEW_CONVERT_EXPR:
8237 /* -- a reinterpret_cast. FIXME not implemented, and this rule
8238 may change to something more specific to type-punning (DR 1312). */
8239 {
8240 tree from = TREE_OPERAND (t, 0);
8241 return (potential_constant_expression_1
8242 (from, TREE_CODE (t) != VIEW_CONVERT_EXPR, flags));
8243 }
8244
8245 case ADDR_EXPR:
8246 /* -- a unary operator & that is applied to an lvalue that
8247 designates an object with thread or automatic storage
8248 duration; */
8249 t = TREE_OPERAND (t, 0);
8250 #if 0
8251 /* FIXME adjust when issue 1197 is fully resolved. For now don't do
8252 any checking here, as we might dereference the pointer later. If
8253 we remove this code, also remove check_automatic_or_tls. */
8254 i = check_automatic_or_tls (t);
8255 if (i == ck_ok)
8256 return true;
8257 if (i == ck_bad)
8258 {
8259 if (flags & tf_error)
8260 error ("address-of an object %qE with thread local or "
8261 "automatic storage is not a constant expression", t);
8262 return false;
8263 }
8264 #endif
8265 return potential_constant_expression_1 (t, any, flags);
8266
8267 case COMPONENT_REF:
8268 case BIT_FIELD_REF:
8269 case ARROW_EXPR:
8270 case OFFSET_REF:
8271 /* -- a class member access unless its postfix-expression is
8272 of literal type or of pointer to literal type. */
8273 /* This test would be redundant, as it follows from the
8274 postfix-expression being a potential constant expression. */
8275 return potential_constant_expression_1 (TREE_OPERAND (t, 0),
8276 want_rval, flags);
8277
8278 case EXPR_PACK_EXPANSION:
8279 return potential_constant_expression_1 (PACK_EXPANSION_PATTERN (t),
8280 want_rval, flags);
8281
8282 case INDIRECT_REF:
8283 {
8284 tree x = TREE_OPERAND (t, 0);
8285 STRIP_NOPS (x);
8286 if (is_this_parameter (x))
8287 {
8288 if (want_rval && DECL_CONTEXT (x)
8289 && DECL_CONSTRUCTOR_P (DECL_CONTEXT (x)))
8290 {
8291 if (flags & tf_error)
8292 sorry ("use of the value of the object being constructed "
8293 "in a constant expression");
8294 return false;
8295 }
8296 return true;
8297 }
8298 return potential_constant_expression_1 (x, rval, flags);
8299 }
8300
8301 case LAMBDA_EXPR:
8302 case DYNAMIC_CAST_EXPR:
8303 case PSEUDO_DTOR_EXPR:
8304 case PREINCREMENT_EXPR:
8305 case POSTINCREMENT_EXPR:
8306 case PREDECREMENT_EXPR:
8307 case POSTDECREMENT_EXPR:
8308 case NEW_EXPR:
8309 case VEC_NEW_EXPR:
8310 case DELETE_EXPR:
8311 case VEC_DELETE_EXPR:
8312 case THROW_EXPR:
8313 case MODIFY_EXPR:
8314 case MODOP_EXPR:
8315 /* GCC internal stuff. */
8316 case VA_ARG_EXPR:
8317 case OBJ_TYPE_REF:
8318 case WITH_CLEANUP_EXPR:
8319 case CLEANUP_POINT_EXPR:
8320 case MUST_NOT_THROW_EXPR:
8321 case TRY_CATCH_EXPR:
8322 case STATEMENT_LIST:
8323 /* Don't bother trying to define a subset of statement-expressions to
8324 be constant-expressions, at least for now. */
8325 case STMT_EXPR:
8326 case EXPR_STMT:
8327 case BIND_EXPR:
8328 case TRANSACTION_EXPR:
8329 case IF_STMT:
8330 case DO_STMT:
8331 case FOR_STMT:
8332 case WHILE_STMT:
8333 if (flags & tf_error)
8334 error ("expression %qE is not a constant-expression", t);
8335 return false;
8336
8337 case TYPEID_EXPR:
8338 /* -- a typeid expression whose operand is of polymorphic
8339 class type; */
8340 {
8341 tree e = TREE_OPERAND (t, 0);
8342 if (!TYPE_P (e) && !type_dependent_expression_p (e)
8343 && TYPE_POLYMORPHIC_P (TREE_TYPE (e)))
8344 {
8345 if (flags & tf_error)
8346 error ("typeid-expression is not a constant expression "
8347 "because %qE is of polymorphic type", e);
8348 return false;
8349 }
8350 return true;
8351 }
8352
8353 case MINUS_EXPR:
8354 /* -- a subtraction where both operands are pointers. */
8355 if (TYPE_PTR_P (TREE_OPERAND (t, 0))
8356 && TYPE_PTR_P (TREE_OPERAND (t, 1)))
8357 {
8358 if (flags & tf_error)
8359 error ("difference of two pointer expressions is not "
8360 "a constant expression");
8361 return false;
8362 }
8363 want_rval = true;
8364 goto binary;
8365
8366 case LT_EXPR:
8367 case LE_EXPR:
8368 case GT_EXPR:
8369 case GE_EXPR:
8370 case EQ_EXPR:
8371 case NE_EXPR:
8372 /* -- a relational or equality operator where at least
8373 one of the operands is a pointer. */
8374 if (TYPE_PTR_P (TREE_OPERAND (t, 0))
8375 || TYPE_PTR_P (TREE_OPERAND (t, 1)))
8376 {
8377 if (flags & tf_error)
8378 error ("pointer comparison expression is not a "
8379 "constant expression");
8380 return false;
8381 }
8382 want_rval = true;
8383 goto binary;
8384
8385 case BIT_NOT_EXPR:
8386 /* A destructor. */
8387 if (TYPE_P (TREE_OPERAND (t, 0)))
8388 return true;
8389 /* else fall through. */
8390
8391 case REALPART_EXPR:
8392 case IMAGPART_EXPR:
8393 case CONJ_EXPR:
8394 case SAVE_EXPR:
8395 case FIX_TRUNC_EXPR:
8396 case FLOAT_EXPR:
8397 case NEGATE_EXPR:
8398 case ABS_EXPR:
8399 case TRUTH_NOT_EXPR:
8400 case FIXED_CONVERT_EXPR:
8401 case UNARY_PLUS_EXPR:
8402 return potential_constant_expression_1 (TREE_OPERAND (t, 0), rval,
8403 flags);
8404
8405 case CAST_EXPR:
8406 case CONST_CAST_EXPR:
8407 case STATIC_CAST_EXPR:
8408 case REINTERPRET_CAST_EXPR:
8409 case IMPLICIT_CONV_EXPR:
8410 return (potential_constant_expression_1
8411 (TREE_OPERAND (t, 0),
8412 TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE, flags));
8413
8414 case PAREN_EXPR:
8415 case NON_DEPENDENT_EXPR:
8416 /* For convenience. */
8417 case RETURN_EXPR:
8418 return potential_constant_expression_1 (TREE_OPERAND (t, 0),
8419 want_rval, flags);
8420
8421 case SCOPE_REF:
8422 return potential_constant_expression_1 (TREE_OPERAND (t, 1),
8423 want_rval, flags);
8424
8425 case TARGET_EXPR:
8426 if (!literal_type_p (TREE_TYPE (t)))
8427 {
8428 if (flags & tf_error)
8429 {
8430 error ("temporary of non-literal type %qT in a "
8431 "constant expression", TREE_TYPE (t));
8432 explain_non_literal_class (TREE_TYPE (t));
8433 }
8434 return false;
8435 }
8436 case INIT_EXPR:
8437 return potential_constant_expression_1 (TREE_OPERAND (t, 1),
8438 rval, flags);
8439
8440 case CONSTRUCTOR:
8441 {
8442 VEC(constructor_elt, gc) *v = CONSTRUCTOR_ELTS (t);
8443 constructor_elt *ce;
8444 for (i = 0; VEC_iterate (constructor_elt, v, i, ce); ++i)
8445 if (!potential_constant_expression_1 (ce->value, want_rval, flags))
8446 return false;
8447 return true;
8448 }
8449
8450 case TREE_LIST:
8451 {
8452 gcc_assert (TREE_PURPOSE (t) == NULL_TREE
8453 || DECL_P (TREE_PURPOSE (t)));
8454 if (!potential_constant_expression_1 (TREE_VALUE (t), want_rval,
8455 flags))
8456 return false;
8457 if (TREE_CHAIN (t) == NULL_TREE)
8458 return true;
8459 return potential_constant_expression_1 (TREE_CHAIN (t), want_rval,
8460 flags);
8461 }
8462
8463 case TRUNC_DIV_EXPR:
8464 case CEIL_DIV_EXPR:
8465 case FLOOR_DIV_EXPR:
8466 case ROUND_DIV_EXPR:
8467 case TRUNC_MOD_EXPR:
8468 case CEIL_MOD_EXPR:
8469 case ROUND_MOD_EXPR:
8470 {
8471 tree denom = TREE_OPERAND (t, 1);
8472 /* We can't call maybe_constant_value on an expression
8473 that hasn't been through fold_non_dependent_expr yet. */
8474 if (!processing_template_decl)
8475 denom = maybe_constant_value (denom);
8476 if (integer_zerop (denom))
8477 {
8478 if (flags & tf_error)
8479 error ("division by zero is not a constant-expression");
8480 return false;
8481 }
8482 else
8483 {
8484 want_rval = true;
8485 goto binary;
8486 }
8487 }
8488
8489 case COMPOUND_EXPR:
8490 {
8491 /* check_return_expr sometimes wraps a TARGET_EXPR in a
8492 COMPOUND_EXPR; don't get confused. Also handle EMPTY_CLASS_EXPR
8493 introduced by build_call_a. */
8494 tree op0 = TREE_OPERAND (t, 0);
8495 tree op1 = TREE_OPERAND (t, 1);
8496 STRIP_NOPS (op1);
8497 if ((TREE_CODE (op0) == TARGET_EXPR && op1 == TARGET_EXPR_SLOT (op0))
8498 || TREE_CODE (op1) == EMPTY_CLASS_EXPR)
8499 return potential_constant_expression_1 (op0, want_rval, flags);
8500 else
8501 goto binary;
8502 }
8503
8504 /* If the first operand is the non-short-circuit constant, look at
8505 the second operand; otherwise we only care about the first one for
8506 potentiality. */
8507 case TRUTH_AND_EXPR:
8508 case TRUTH_ANDIF_EXPR:
8509 tmp = boolean_true_node;
8510 goto truth;
8511 case TRUTH_OR_EXPR:
8512 case TRUTH_ORIF_EXPR:
8513 tmp = boolean_false_node;
8514 truth:
8515 if (TREE_OPERAND (t, 0) == tmp)
8516 return potential_constant_expression_1 (TREE_OPERAND (t, 1), rval, flags);
8517 else
8518 return potential_constant_expression_1 (TREE_OPERAND (t, 0), rval, flags);
8519
8520 case PLUS_EXPR:
8521 case MULT_EXPR:
8522 case POINTER_PLUS_EXPR:
8523 case RDIV_EXPR:
8524 case EXACT_DIV_EXPR:
8525 case MIN_EXPR:
8526 case MAX_EXPR:
8527 case LSHIFT_EXPR:
8528 case RSHIFT_EXPR:
8529 case LROTATE_EXPR:
8530 case RROTATE_EXPR:
8531 case BIT_IOR_EXPR:
8532 case BIT_XOR_EXPR:
8533 case BIT_AND_EXPR:
8534 case TRUTH_XOR_EXPR:
8535 case UNORDERED_EXPR:
8536 case ORDERED_EXPR:
8537 case UNLT_EXPR:
8538 case UNLE_EXPR:
8539 case UNGT_EXPR:
8540 case UNGE_EXPR:
8541 case UNEQ_EXPR:
8542 case LTGT_EXPR:
8543 case RANGE_EXPR:
8544 case COMPLEX_EXPR:
8545 want_rval = true;
8546 /* Fall through. */
8547 case ARRAY_REF:
8548 case ARRAY_RANGE_REF:
8549 case MEMBER_REF:
8550 case DOTSTAR_EXPR:
8551 binary:
8552 for (i = 0; i < 2; ++i)
8553 if (!potential_constant_expression_1 (TREE_OPERAND (t, i),
8554 want_rval, flags))
8555 return false;
8556 return true;
8557
8558 case FMA_EXPR:
8559 for (i = 0; i < 3; ++i)
8560 if (!potential_constant_expression_1 (TREE_OPERAND (t, i),
8561 true, flags))
8562 return false;
8563 return true;
8564
8565 case COND_EXPR:
8566 case VEC_COND_EXPR:
8567 /* If the condition is a known constant, we know which of the legs we
8568 care about; otherwise we only require that the condition and
8569 either of the legs be potentially constant. */
8570 tmp = TREE_OPERAND (t, 0);
8571 if (!potential_constant_expression_1 (tmp, rval, flags))
8572 return false;
8573 else if (integer_zerop (tmp))
8574 return potential_constant_expression_1 (TREE_OPERAND (t, 2),
8575 want_rval, flags);
8576 else if (TREE_CODE (tmp) == INTEGER_CST)
8577 return potential_constant_expression_1 (TREE_OPERAND (t, 1),
8578 want_rval, flags);
8579 for (i = 1; i < 3; ++i)
8580 if (potential_constant_expression_1 (TREE_OPERAND (t, i),
8581 want_rval, tf_none))
8582 return true;
8583 if (flags & tf_error)
8584 error ("expression %qE is not a constant-expression", t);
8585 return false;
8586
8587 case VEC_INIT_EXPR:
8588 if (VEC_INIT_EXPR_IS_CONSTEXPR (t))
8589 return true;
8590 if (flags & tf_error)
8591 {
8592 error ("non-constant array initialization");
8593 diagnose_non_constexpr_vec_init (t);
8594 }
8595 return false;
8596
8597 case OMP_ATOMIC:
8598 case OMP_ATOMIC_READ:
8599 case OMP_ATOMIC_CAPTURE_OLD:
8600 case OMP_ATOMIC_CAPTURE_NEW:
8601 return false;
8602
8603 default:
8604 sorry ("unexpected AST of kind %s", tree_code_name[TREE_CODE (t)]);
8605 gcc_unreachable();
8606 return false;
8607 }
8608 }
8609
8610 /* The main entry point to the above. */
8611
8612 bool
potential_constant_expression(tree t)8613 potential_constant_expression (tree t)
8614 {
8615 return potential_constant_expression_1 (t, false, tf_none);
8616 }
8617
8618 /* As above, but require a constant rvalue. */
8619
8620 bool
potential_rvalue_constant_expression(tree t)8621 potential_rvalue_constant_expression (tree t)
8622 {
8623 return potential_constant_expression_1 (t, true, tf_none);
8624 }
8625
8626 /* Like above, but complain about non-constant expressions. */
8627
8628 bool
require_potential_constant_expression(tree t)8629 require_potential_constant_expression (tree t)
8630 {
8631 return potential_constant_expression_1 (t, false, tf_warning_or_error);
8632 }
8633
8634 /* Cross product of the above. */
8635
8636 bool
require_potential_rvalue_constant_expression(tree t)8637 require_potential_rvalue_constant_expression (tree t)
8638 {
8639 return potential_constant_expression_1 (t, true, tf_warning_or_error);
8640 }
8641
8642 /* Constructor for a lambda expression. */
8643
8644 tree
build_lambda_expr(void)8645 build_lambda_expr (void)
8646 {
8647 tree lambda = make_node (LAMBDA_EXPR);
8648 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda) = CPLD_NONE;
8649 LAMBDA_EXPR_CAPTURE_LIST (lambda) = NULL_TREE;
8650 LAMBDA_EXPR_THIS_CAPTURE (lambda) = NULL_TREE;
8651 LAMBDA_EXPR_PENDING_PROXIES (lambda) = NULL;
8652 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE;
8653 LAMBDA_EXPR_MUTABLE_P (lambda) = false;
8654 return lambda;
8655 }
8656
8657 /* Create the closure object for a LAMBDA_EXPR. */
8658
8659 tree
build_lambda_object(tree lambda_expr)8660 build_lambda_object (tree lambda_expr)
8661 {
8662 /* Build aggregate constructor call.
8663 - cp_parser_braced_list
8664 - cp_parser_functional_cast */
8665 VEC(constructor_elt,gc) *elts = NULL;
8666 tree node, expr, type;
8667 location_t saved_loc;
8668
8669 if (processing_template_decl)
8670 return lambda_expr;
8671
8672 /* Make sure any error messages refer to the lambda-introducer. */
8673 saved_loc = input_location;
8674 input_location = LAMBDA_EXPR_LOCATION (lambda_expr);
8675
8676 for (node = LAMBDA_EXPR_CAPTURE_LIST (lambda_expr);
8677 node;
8678 node = TREE_CHAIN (node))
8679 {
8680 tree field = TREE_PURPOSE (node);
8681 tree val = TREE_VALUE (node);
8682
8683 if (field == error_mark_node)
8684 {
8685 expr = error_mark_node;
8686 goto out;
8687 }
8688
8689 if (DECL_P (val))
8690 mark_used (val);
8691
8692 /* Mere mortals can't copy arrays with aggregate initialization, so
8693 do some magic to make it work here. */
8694 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE)
8695 val = build_array_copy (val);
8696 else if (DECL_NORMAL_CAPTURE_P (field)
8697 && TREE_CODE (TREE_TYPE (field)) != REFERENCE_TYPE)
8698 {
8699 /* "the entities that are captured by copy are used to
8700 direct-initialize each corresponding non-static data
8701 member of the resulting closure object."
8702
8703 There's normally no way to express direct-initialization
8704 from an element of a CONSTRUCTOR, so we build up a special
8705 TARGET_EXPR to bypass the usual copy-initialization. */
8706 val = force_rvalue (val, tf_warning_or_error);
8707 if (TREE_CODE (val) == TARGET_EXPR)
8708 TARGET_EXPR_DIRECT_INIT_P (val) = true;
8709 }
8710
8711 CONSTRUCTOR_APPEND_ELT (elts, DECL_NAME (field), val);
8712 }
8713
8714 expr = build_constructor (init_list_type_node, elts);
8715 CONSTRUCTOR_IS_DIRECT_INIT (expr) = 1;
8716
8717 /* N2927: "[The closure] class type is not an aggregate."
8718 But we briefly treat it as an aggregate to make this simpler. */
8719 type = LAMBDA_EXPR_CLOSURE (lambda_expr);
8720 CLASSTYPE_NON_AGGREGATE (type) = 0;
8721 expr = finish_compound_literal (type, expr, tf_warning_or_error);
8722 CLASSTYPE_NON_AGGREGATE (type) = 1;
8723
8724 out:
8725 input_location = saved_loc;
8726 return expr;
8727 }
8728
8729 /* Return an initialized RECORD_TYPE for LAMBDA.
8730 LAMBDA must have its explicit captures already. */
8731
8732 tree
begin_lambda_type(tree lambda)8733 begin_lambda_type (tree lambda)
8734 {
8735 tree type;
8736
8737 {
8738 /* Unique name. This is just like an unnamed class, but we cannot use
8739 make_anon_name because of certain checks against TYPE_ANONYMOUS_P. */
8740 tree name;
8741 name = make_lambda_name ();
8742
8743 /* Create the new RECORD_TYPE for this lambda. */
8744 type = xref_tag (/*tag_code=*/record_type,
8745 name,
8746 /*scope=*/ts_within_enclosing_non_class,
8747 /*template_header_p=*/false);
8748 }
8749
8750 /* Designate it as a struct so that we can use aggregate initialization. */
8751 CLASSTYPE_DECLARED_CLASS (type) = false;
8752
8753 /* Clear base types. */
8754 xref_basetypes (type, /*bases=*/NULL_TREE);
8755
8756 /* Start the class. */
8757 type = begin_class_definition (type);
8758 if (type == error_mark_node)
8759 return error_mark_node;
8760
8761 /* Cross-reference the expression and the type. */
8762 LAMBDA_EXPR_CLOSURE (lambda) = type;
8763 CLASSTYPE_LAMBDA_EXPR (type) = lambda;
8764
8765 return type;
8766 }
8767
8768 /* Returns the type to use for the return type of the operator() of a
8769 closure class. */
8770
8771 tree
lambda_return_type(tree expr)8772 lambda_return_type (tree expr)
8773 {
8774 tree type;
8775 if (type_unknown_p (expr)
8776 || BRACE_ENCLOSED_INITIALIZER_P (expr))
8777 {
8778 cxx_incomplete_type_error (expr, TREE_TYPE (expr));
8779 return void_type_node;
8780 }
8781 if (type_dependent_expression_p (expr))
8782 type = dependent_lambda_return_type_node;
8783 else
8784 type = cv_unqualified (type_decays_to (unlowered_expr_type (expr)));
8785 return type;
8786 }
8787
8788 /* Given a LAMBDA_EXPR or closure type LAMBDA, return the op() of the
8789 closure type. */
8790
8791 tree
lambda_function(tree lambda)8792 lambda_function (tree lambda)
8793 {
8794 tree type;
8795 if (TREE_CODE (lambda) == LAMBDA_EXPR)
8796 type = LAMBDA_EXPR_CLOSURE (lambda);
8797 else
8798 type = lambda;
8799 gcc_assert (LAMBDA_TYPE_P (type));
8800 /* Don't let debug_tree cause instantiation. */
8801 if (CLASSTYPE_TEMPLATE_INSTANTIATION (type)
8802 && !COMPLETE_OR_OPEN_TYPE_P (type))
8803 return NULL_TREE;
8804 lambda = lookup_member (type, ansi_opname (CALL_EXPR),
8805 /*protect=*/0, /*want_type=*/false,
8806 tf_warning_or_error);
8807 if (lambda)
8808 lambda = BASELINK_FUNCTIONS (lambda);
8809 return lambda;
8810 }
8811
8812 /* Returns the type to use for the FIELD_DECL corresponding to the
8813 capture of EXPR.
8814 The caller should add REFERENCE_TYPE for capture by reference. */
8815
8816 tree
lambda_capture_field_type(tree expr)8817 lambda_capture_field_type (tree expr)
8818 {
8819 tree type;
8820 if (type_dependent_expression_p (expr)
8821 && !(TREE_TYPE (expr) && TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE))
8822 {
8823 type = cxx_make_type (DECLTYPE_TYPE);
8824 DECLTYPE_TYPE_EXPR (type) = expr;
8825 DECLTYPE_FOR_LAMBDA_CAPTURE (type) = true;
8826 SET_TYPE_STRUCTURAL_EQUALITY (type);
8827 }
8828 else
8829 type = non_reference (unlowered_expr_type (expr));
8830 return type;
8831 }
8832
8833 /* Recompute the return type for LAMBDA with body of the form:
8834 { return EXPR ; } */
8835
8836 void
apply_lambda_return_type(tree lambda,tree return_type)8837 apply_lambda_return_type (tree lambda, tree return_type)
8838 {
8839 tree fco = lambda_function (lambda);
8840 tree result;
8841
8842 LAMBDA_EXPR_RETURN_TYPE (lambda) = return_type;
8843
8844 if (return_type == error_mark_node)
8845 return;
8846 if (TREE_TYPE (TREE_TYPE (fco)) == return_type)
8847 return;
8848
8849 /* TREE_TYPE (FUNCTION_DECL) == METHOD_TYPE
8850 TREE_TYPE (METHOD_TYPE) == return-type */
8851 TREE_TYPE (fco) = change_return_type (return_type, TREE_TYPE (fco));
8852
8853 result = DECL_RESULT (fco);
8854 if (result == NULL_TREE)
8855 return;
8856
8857 /* We already have a DECL_RESULT from start_preparsed_function.
8858 Now we need to redo the work it and allocate_struct_function
8859 did to reflect the new type. */
8860 gcc_assert (current_function_decl == fco);
8861 result = build_decl (input_location, RESULT_DECL, NULL_TREE,
8862 TYPE_MAIN_VARIANT (return_type));
8863 DECL_ARTIFICIAL (result) = 1;
8864 DECL_IGNORED_P (result) = 1;
8865 cp_apply_type_quals_to_decl (cp_type_quals (return_type),
8866 result);
8867
8868 DECL_RESULT (fco) = result;
8869
8870 if (!processing_template_decl && aggregate_value_p (result, fco))
8871 {
8872 #ifdef PCC_STATIC_STRUCT_RETURN
8873 cfun->returns_pcc_struct = 1;
8874 #endif
8875 cfun->returns_struct = 1;
8876 }
8877
8878 }
8879
8880 /* DECL is a local variable or parameter from the surrounding scope of a
8881 lambda-expression. Returns the decltype for a use of the capture field
8882 for DECL even if it hasn't been captured yet. */
8883
8884 static tree
capture_decltype(tree decl)8885 capture_decltype (tree decl)
8886 {
8887 tree lam = CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (current_function_decl));
8888 /* FIXME do lookup instead of list walk? */
8889 tree cap = value_member (decl, LAMBDA_EXPR_CAPTURE_LIST (lam));
8890 tree type;
8891
8892 if (cap)
8893 type = TREE_TYPE (TREE_PURPOSE (cap));
8894 else
8895 switch (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lam))
8896 {
8897 case CPLD_NONE:
8898 error ("%qD is not captured", decl);
8899 return error_mark_node;
8900
8901 case CPLD_COPY:
8902 type = TREE_TYPE (decl);
8903 if (TREE_CODE (type) == REFERENCE_TYPE
8904 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
8905 type = TREE_TYPE (type);
8906 break;
8907
8908 case CPLD_REFERENCE:
8909 type = TREE_TYPE (decl);
8910 if (TREE_CODE (type) != REFERENCE_TYPE)
8911 type = build_reference_type (TREE_TYPE (decl));
8912 break;
8913
8914 default:
8915 gcc_unreachable ();
8916 }
8917
8918 if (TREE_CODE (type) != REFERENCE_TYPE)
8919 {
8920 if (!LAMBDA_EXPR_MUTABLE_P (lam))
8921 type = cp_build_qualified_type (type, (cp_type_quals (type)
8922 |TYPE_QUAL_CONST));
8923 type = build_reference_type (type);
8924 }
8925 return type;
8926 }
8927
8928 /* Returns true iff DECL is a lambda capture proxy variable created by
8929 build_capture_proxy. */
8930
8931 bool
is_capture_proxy(tree decl)8932 is_capture_proxy (tree decl)
8933 {
8934 return (TREE_CODE (decl) == VAR_DECL
8935 && DECL_HAS_VALUE_EXPR_P (decl)
8936 && !DECL_ANON_UNION_VAR_P (decl)
8937 && LAMBDA_FUNCTION_P (DECL_CONTEXT (decl)));
8938 }
8939
8940 /* Returns true iff DECL is a capture proxy for a normal capture
8941 (i.e. without explicit initializer). */
8942
8943 bool
is_normal_capture_proxy(tree decl)8944 is_normal_capture_proxy (tree decl)
8945 {
8946 tree val;
8947
8948 if (!is_capture_proxy (decl))
8949 /* It's not a capture proxy. */
8950 return false;
8951
8952 /* It is a capture proxy, is it a normal capture? */
8953 val = DECL_VALUE_EXPR (decl);
8954 gcc_assert (TREE_CODE (val) == COMPONENT_REF);
8955 val = TREE_OPERAND (val, 1);
8956 return DECL_NORMAL_CAPTURE_P (val);
8957 }
8958
8959 /* VAR is a capture proxy created by build_capture_proxy; add it to the
8960 current function, which is the operator() for the appropriate lambda. */
8961
8962 void
insert_capture_proxy(tree var)8963 insert_capture_proxy (tree var)
8964 {
8965 cp_binding_level *b;
8966 tree stmt_list;
8967
8968 /* Put the capture proxy in the extra body block so that it won't clash
8969 with a later local variable. */
8970 b = current_binding_level;
8971 for (;;)
8972 {
8973 cp_binding_level *n = b->level_chain;
8974 if (n->kind == sk_function_parms)
8975 break;
8976 b = n;
8977 }
8978 pushdecl_with_scope (var, b, false);
8979
8980 /* And put a DECL_EXPR in the STATEMENT_LIST for the same block. */
8981 var = build_stmt (DECL_SOURCE_LOCATION (var), DECL_EXPR, var);
8982 stmt_list = VEC_index (tree, stmt_list_stack, 1);
8983 gcc_assert (stmt_list);
8984 append_to_statement_list_force (var, &stmt_list);
8985 }
8986
8987 /* We've just finished processing a lambda; if the containing scope is also
8988 a lambda, insert any capture proxies that were created while processing
8989 the nested lambda. */
8990
8991 void
insert_pending_capture_proxies(void)8992 insert_pending_capture_proxies (void)
8993 {
8994 tree lam;
8995 VEC(tree,gc) *proxies;
8996 unsigned i;
8997
8998 if (!current_function_decl || !LAMBDA_FUNCTION_P (current_function_decl))
8999 return;
9000
9001 lam = CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (current_function_decl));
9002 proxies = LAMBDA_EXPR_PENDING_PROXIES (lam);
9003 for (i = 0; i < VEC_length (tree, proxies); ++i)
9004 {
9005 tree var = VEC_index (tree, proxies, i);
9006 insert_capture_proxy (var);
9007 }
9008 release_tree_vector (LAMBDA_EXPR_PENDING_PROXIES (lam));
9009 LAMBDA_EXPR_PENDING_PROXIES (lam) = NULL;
9010 }
9011
9012 /* Given REF, a COMPONENT_REF designating a field in the lambda closure,
9013 return the type we want the proxy to have: the type of the field itself,
9014 with added const-qualification if the lambda isn't mutable and the
9015 capture is by value. */
9016
9017 tree
lambda_proxy_type(tree ref)9018 lambda_proxy_type (tree ref)
9019 {
9020 tree type;
9021 if (REFERENCE_REF_P (ref))
9022 ref = TREE_OPERAND (ref, 0);
9023 type = TREE_TYPE (ref);
9024 if (!dependent_type_p (type)
9025 || (type && TREE_CODE (type) == POINTER_TYPE))
9026 return type;
9027 type = cxx_make_type (DECLTYPE_TYPE);
9028 DECLTYPE_TYPE_EXPR (type) = ref;
9029 DECLTYPE_FOR_LAMBDA_PROXY (type) = true;
9030 SET_TYPE_STRUCTURAL_EQUALITY (type);
9031 return type;
9032 }
9033
9034 /* MEMBER is a capture field in a lambda closure class. Now that we're
9035 inside the operator(), build a placeholder var for future lookups and
9036 debugging. */
9037
9038 tree
build_capture_proxy(tree member)9039 build_capture_proxy (tree member)
9040 {
9041 tree var, object, fn, closure, name, lam, type;
9042
9043 closure = DECL_CONTEXT (member);
9044 fn = lambda_function (closure);
9045 lam = CLASSTYPE_LAMBDA_EXPR (closure);
9046
9047 /* The proxy variable forwards to the capture field. */
9048 object = build_fold_indirect_ref (DECL_ARGUMENTS (fn));
9049 object = finish_non_static_data_member (member, object, NULL_TREE);
9050 if (REFERENCE_REF_P (object))
9051 object = TREE_OPERAND (object, 0);
9052
9053 /* Remove the __ inserted by add_capture. */
9054 name = get_identifier (IDENTIFIER_POINTER (DECL_NAME (member)) + 2);
9055
9056 type = lambda_proxy_type (object);
9057 var = build_decl (input_location, VAR_DECL, name, type);
9058 SET_DECL_VALUE_EXPR (var, object);
9059 DECL_HAS_VALUE_EXPR_P (var) = 1;
9060 DECL_ARTIFICIAL (var) = 1;
9061 TREE_USED (var) = 1;
9062 DECL_CONTEXT (var) = fn;
9063
9064 if (name == this_identifier)
9065 {
9066 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (lam) == member);
9067 LAMBDA_EXPR_THIS_CAPTURE (lam) = var;
9068 }
9069
9070 if (fn == current_function_decl)
9071 insert_capture_proxy (var);
9072 else
9073 VEC_safe_push (tree, gc, LAMBDA_EXPR_PENDING_PROXIES (lam), var);
9074
9075 return var;
9076 }
9077
9078 /* From an ID and INITIALIZER, create a capture (by reference if
9079 BY_REFERENCE_P is true), add it to the capture-list for LAMBDA,
9080 and return it. */
9081
9082 tree
add_capture(tree lambda,tree id,tree initializer,bool by_reference_p,bool explicit_init_p)9083 add_capture (tree lambda, tree id, tree initializer, bool by_reference_p,
9084 bool explicit_init_p)
9085 {
9086 char *buf;
9087 tree type, member, name;
9088
9089 type = lambda_capture_field_type (initializer);
9090 if (by_reference_p)
9091 {
9092 type = build_reference_type (type);
9093 if (!real_lvalue_p (initializer))
9094 error ("cannot capture %qE by reference", initializer);
9095 }
9096 else
9097 /* Capture by copy requires a complete type. */
9098 type = complete_type (type);
9099
9100 /* Add __ to the beginning of the field name so that user code
9101 won't find the field with name lookup. We can't just leave the name
9102 unset because template instantiation uses the name to find
9103 instantiated fields. */
9104 buf = (char *) alloca (IDENTIFIER_LENGTH (id) + 3);
9105 buf[1] = buf[0] = '_';
9106 memcpy (buf + 2, IDENTIFIER_POINTER (id),
9107 IDENTIFIER_LENGTH (id) + 1);
9108 name = get_identifier (buf);
9109
9110 /* If TREE_TYPE isn't set, we're still in the introducer, so check
9111 for duplicates. */
9112 if (!LAMBDA_EXPR_CLOSURE (lambda))
9113 {
9114 if (IDENTIFIER_MARKED (name))
9115 {
9116 pedwarn (input_location, 0,
9117 "already captured %qD in lambda expression", id);
9118 return NULL_TREE;
9119 }
9120 IDENTIFIER_MARKED (name) = true;
9121 }
9122
9123 /* Make member variable. */
9124 member = build_lang_decl (FIELD_DECL, name, type);
9125
9126 if (!explicit_init_p)
9127 /* Normal captures are invisible to name lookup but uses are replaced
9128 with references to the capture field; we implement this by only
9129 really making them invisible in unevaluated context; see
9130 qualify_lookup. For now, let's make explicitly initialized captures
9131 always visible. */
9132 DECL_NORMAL_CAPTURE_P (member) = true;
9133
9134 if (id == this_identifier)
9135 LAMBDA_EXPR_THIS_CAPTURE (lambda) = member;
9136
9137 /* Add it to the appropriate closure class if we've started it. */
9138 if (current_class_type
9139 && current_class_type == LAMBDA_EXPR_CLOSURE (lambda))
9140 finish_member_declaration (member);
9141
9142 LAMBDA_EXPR_CAPTURE_LIST (lambda)
9143 = tree_cons (member, initializer, LAMBDA_EXPR_CAPTURE_LIST (lambda));
9144
9145 if (LAMBDA_EXPR_CLOSURE (lambda))
9146 return build_capture_proxy (member);
9147 /* For explicit captures we haven't started the function yet, so we wait
9148 and build the proxy from cp_parser_lambda_body. */
9149 return NULL_TREE;
9150 }
9151
9152 /* Register all the capture members on the list CAPTURES, which is the
9153 LAMBDA_EXPR_CAPTURE_LIST for the lambda after the introducer. */
9154
9155 void
register_capture_members(tree captures)9156 register_capture_members (tree captures)
9157 {
9158 if (captures == NULL_TREE)
9159 return;
9160
9161 register_capture_members (TREE_CHAIN (captures));
9162 /* We set this in add_capture to avoid duplicates. */
9163 IDENTIFIER_MARKED (DECL_NAME (TREE_PURPOSE (captures))) = false;
9164 finish_member_declaration (TREE_PURPOSE (captures));
9165 }
9166
9167 /* Similar to add_capture, except this works on a stack of nested lambdas.
9168 BY_REFERENCE_P in this case is derived from the default capture mode.
9169 Returns the capture for the lambda at the bottom of the stack. */
9170
9171 tree
add_default_capture(tree lambda_stack,tree id,tree initializer)9172 add_default_capture (tree lambda_stack, tree id, tree initializer)
9173 {
9174 bool this_capture_p = (id == this_identifier);
9175
9176 tree var = NULL_TREE;
9177
9178 tree saved_class_type = current_class_type;
9179
9180 tree node;
9181
9182 for (node = lambda_stack;
9183 node;
9184 node = TREE_CHAIN (node))
9185 {
9186 tree lambda = TREE_VALUE (node);
9187
9188 current_class_type = LAMBDA_EXPR_CLOSURE (lambda);
9189 var = add_capture (lambda,
9190 id,
9191 initializer,
9192 /*by_reference_p=*/
9193 (!this_capture_p
9194 && (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda)
9195 == CPLD_REFERENCE)),
9196 /*explicit_init_p=*/false);
9197 initializer = convert_from_reference (var);
9198 }
9199
9200 current_class_type = saved_class_type;
9201
9202 return var;
9203 }
9204
9205 /* Return the capture pertaining to a use of 'this' in LAMBDA, in the form of an
9206 INDIRECT_REF, possibly adding it through default capturing. */
9207
9208 tree
lambda_expr_this_capture(tree lambda)9209 lambda_expr_this_capture (tree lambda)
9210 {
9211 tree result;
9212
9213 tree this_capture = LAMBDA_EXPR_THIS_CAPTURE (lambda);
9214
9215 /* Try to default capture 'this' if we can. */
9216 if (!this_capture
9217 && LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda) != CPLD_NONE)
9218 {
9219 tree containing_function = TYPE_CONTEXT (LAMBDA_EXPR_CLOSURE (lambda));
9220 tree lambda_stack = tree_cons (NULL_TREE, lambda, NULL_TREE);
9221 tree init = NULL_TREE;
9222
9223 /* If we are in a lambda function, we can move out until we hit:
9224 1. a non-lambda function,
9225 2. a lambda function capturing 'this', or
9226 3. a non-default capturing lambda function. */
9227 while (LAMBDA_FUNCTION_P (containing_function))
9228 {
9229 tree lambda
9230 = CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (containing_function));
9231
9232 if (LAMBDA_EXPR_THIS_CAPTURE (lambda))
9233 {
9234 /* An outer lambda has already captured 'this'. */
9235 init = LAMBDA_EXPR_THIS_CAPTURE (lambda);
9236 break;
9237 }
9238
9239 if (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda) == CPLD_NONE)
9240 /* An outer lambda won't let us capture 'this'. */
9241 break;
9242
9243 lambda_stack = tree_cons (NULL_TREE,
9244 lambda,
9245 lambda_stack);
9246
9247 containing_function = decl_function_context (containing_function);
9248 }
9249
9250 if (!init && DECL_NONSTATIC_MEMBER_FUNCTION_P (containing_function)
9251 && !LAMBDA_FUNCTION_P (containing_function))
9252 /* First parameter is 'this'. */
9253 init = DECL_ARGUMENTS (containing_function);
9254
9255 if (init)
9256 this_capture = add_default_capture (lambda_stack,
9257 /*id=*/this_identifier,
9258 init);
9259 }
9260
9261 if (!this_capture)
9262 {
9263 error ("%<this%> was not captured for this lambda function");
9264 result = error_mark_node;
9265 }
9266 else
9267 {
9268 /* To make sure that current_class_ref is for the lambda. */
9269 gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (current_class_ref))
9270 == LAMBDA_EXPR_CLOSURE (lambda));
9271
9272 result = this_capture;
9273
9274 /* If 'this' is captured, each use of 'this' is transformed into an
9275 access to the corresponding unnamed data member of the closure
9276 type cast (_expr.cast_ 5.4) to the type of 'this'. [ The cast
9277 ensures that the transformed expression is an rvalue. ] */
9278 result = rvalue (result);
9279 }
9280
9281 return result;
9282 }
9283
9284 /* Returns the method basetype of the innermost non-lambda function, or
9285 NULL_TREE if none. */
9286
9287 tree
nonlambda_method_basetype(void)9288 nonlambda_method_basetype (void)
9289 {
9290 tree fn, type;
9291 if (!current_class_ref)
9292 return NULL_TREE;
9293
9294 type = current_class_type;
9295 if (!LAMBDA_TYPE_P (type))
9296 return type;
9297
9298 /* Find the nearest enclosing non-lambda function. */
9299 fn = TYPE_NAME (type);
9300 do
9301 fn = decl_function_context (fn);
9302 while (fn && LAMBDA_FUNCTION_P (fn));
9303
9304 if (!fn || !DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9305 return NULL_TREE;
9306
9307 return TYPE_METHOD_BASETYPE (TREE_TYPE (fn));
9308 }
9309
9310 /* If the closure TYPE has a static op(), also add a conversion to function
9311 pointer. */
9312
9313 void
maybe_add_lambda_conv_op(tree type)9314 maybe_add_lambda_conv_op (tree type)
9315 {
9316 bool nested = (current_function_decl != NULL_TREE);
9317 tree callop = lambda_function (type);
9318 tree rettype, name, fntype, fn, body, compound_stmt;
9319 tree thistype, stattype, statfn, convfn, call, arg;
9320 VEC (tree, gc) *argvec;
9321
9322 if (LAMBDA_EXPR_CAPTURE_LIST (CLASSTYPE_LAMBDA_EXPR (type)) != NULL_TREE)
9323 return;
9324
9325 if (processing_template_decl)
9326 return;
9327
9328 stattype = build_function_type (TREE_TYPE (TREE_TYPE (callop)),
9329 FUNCTION_ARG_CHAIN (callop));
9330
9331 /* First build up the conversion op. */
9332
9333 rettype = build_pointer_type (stattype);
9334 name = mangle_conv_op_name_for_type (rettype);
9335 thistype = cp_build_qualified_type (type, TYPE_QUAL_CONST);
9336 fntype = build_method_type_directly (thistype, rettype, void_list_node);
9337 fn = convfn = build_lang_decl (FUNCTION_DECL, name, fntype);
9338 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (callop);
9339
9340 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_pfn
9341 && DECL_ALIGN (fn) < 2 * BITS_PER_UNIT)
9342 DECL_ALIGN (fn) = 2 * BITS_PER_UNIT;
9343
9344 SET_OVERLOADED_OPERATOR_CODE (fn, TYPE_EXPR);
9345 grokclassfn (type, fn, NO_SPECIAL);
9346 set_linkage_according_to_type (type, fn);
9347 rest_of_decl_compilation (fn, toplevel_bindings_p (), at_eof);
9348 DECL_IN_AGGR_P (fn) = 1;
9349 DECL_ARTIFICIAL (fn) = 1;
9350 DECL_NOT_REALLY_EXTERN (fn) = 1;
9351 DECL_DECLARED_INLINE_P (fn) = 1;
9352 DECL_ARGUMENTS (fn) = build_this_parm (fntype, TYPE_QUAL_CONST);
9353 if (nested)
9354 DECL_INTERFACE_KNOWN (fn) = 1;
9355
9356 add_method (type, fn, NULL_TREE);
9357
9358 /* Generic thunk code fails for varargs; we'll complain in mark_used if
9359 the conversion op is used. */
9360 if (varargs_function_p (callop))
9361 {
9362 DECL_DELETED_FN (fn) = 1;
9363 return;
9364 }
9365
9366 /* Now build up the thunk to be returned. */
9367
9368 name = get_identifier ("_FUN");
9369 fn = statfn = build_lang_decl (FUNCTION_DECL, name, stattype);
9370 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (callop);
9371 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_pfn
9372 && DECL_ALIGN (fn) < 2 * BITS_PER_UNIT)
9373 DECL_ALIGN (fn) = 2 * BITS_PER_UNIT;
9374 grokclassfn (type, fn, NO_SPECIAL);
9375 set_linkage_according_to_type (type, fn);
9376 rest_of_decl_compilation (fn, toplevel_bindings_p (), at_eof);
9377 DECL_IN_AGGR_P (fn) = 1;
9378 DECL_ARTIFICIAL (fn) = 1;
9379 DECL_NOT_REALLY_EXTERN (fn) = 1;
9380 DECL_DECLARED_INLINE_P (fn) = 1;
9381 DECL_STATIC_FUNCTION_P (fn) = 1;
9382 DECL_ARGUMENTS (fn) = copy_list (DECL_CHAIN (DECL_ARGUMENTS (callop)));
9383 for (arg = DECL_ARGUMENTS (fn); arg; arg = DECL_CHAIN (arg))
9384 DECL_CONTEXT (arg) = fn;
9385 if (nested)
9386 DECL_INTERFACE_KNOWN (fn) = 1;
9387
9388 add_method (type, fn, NULL_TREE);
9389
9390 if (nested)
9391 push_function_context ();
9392 else
9393 /* Still increment function_depth so that we don't GC in the
9394 middle of an expression. */
9395 ++function_depth;
9396
9397 /* Generate the body of the thunk. */
9398
9399 start_preparsed_function (statfn, NULL_TREE,
9400 SF_PRE_PARSED | SF_INCLASS_INLINE);
9401 if (DECL_ONE_ONLY (statfn))
9402 {
9403 /* Put the thunk in the same comdat group as the call op. */
9404 cgraph_add_to_same_comdat_group (cgraph_get_create_node (statfn),
9405 cgraph_get_create_node (callop));
9406 }
9407 body = begin_function_body ();
9408 compound_stmt = begin_compound_stmt (0);
9409
9410 arg = build1 (NOP_EXPR, TREE_TYPE (DECL_ARGUMENTS (callop)),
9411 null_pointer_node);
9412 argvec = make_tree_vector ();
9413 VEC_quick_push (tree, argvec, arg);
9414 for (arg = DECL_ARGUMENTS (statfn); arg; arg = DECL_CHAIN (arg))
9415 {
9416 mark_exp_read (arg);
9417 VEC_safe_push (tree, gc, argvec, arg);
9418 }
9419 call = build_call_a (callop, VEC_length (tree, argvec),
9420 VEC_address (tree, argvec));
9421 CALL_FROM_THUNK_P (call) = 1;
9422 if (MAYBE_CLASS_TYPE_P (TREE_TYPE (call)))
9423 call = build_cplus_new (TREE_TYPE (call), call, tf_warning_or_error);
9424 call = convert_from_reference (call);
9425 finish_return_stmt (call);
9426
9427 finish_compound_stmt (compound_stmt);
9428 finish_function_body (body);
9429
9430 expand_or_defer_fn (finish_function (2));
9431
9432 /* Generate the body of the conversion op. */
9433
9434 start_preparsed_function (convfn, NULL_TREE,
9435 SF_PRE_PARSED | SF_INCLASS_INLINE);
9436 body = begin_function_body ();
9437 compound_stmt = begin_compound_stmt (0);
9438
9439 /* decl_needed_p needs to see that it's used. */
9440 TREE_USED (statfn) = 1;
9441 finish_return_stmt (decay_conversion (statfn));
9442
9443 finish_compound_stmt (compound_stmt);
9444 finish_function_body (body);
9445
9446 expand_or_defer_fn (finish_function (2));
9447
9448 if (nested)
9449 pop_function_context ();
9450 else
9451 --function_depth;
9452 }
9453
9454 /* Returns true iff VAL is a lambda-related declaration which should
9455 be ignored by unqualified lookup. */
9456
9457 bool
is_lambda_ignored_entity(tree val)9458 is_lambda_ignored_entity (tree val)
9459 {
9460 /* In unevaluated context, look past normal capture proxies. */
9461 if (cp_unevaluated_operand && is_normal_capture_proxy (val))
9462 return true;
9463
9464 /* Always ignore lambda fields, their names are only for debugging. */
9465 if (TREE_CODE (val) == FIELD_DECL
9466 && CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (val)))
9467 return true;
9468
9469 /* None of the lookups that use qualify_lookup want the op() from the
9470 lambda; they want the one from the enclosing class. */
9471 if (TREE_CODE (val) == FUNCTION_DECL && LAMBDA_FUNCTION_P (val))
9472 return true;
9473
9474 return false;
9475 }
9476
9477 #include "gt-cp-semantics.h"
9478