Daily bump.
[official-gcc.git] / gcc / valtrack.c
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1 /* Infrastructure for tracking user variable locations and values
2 throughout compilation.
3 Copyright (C) 2010-2015 Free Software Foundation, Inc.
4 Contributed by Alexandre Oliva <aoliva@redhat.com>.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
26 #include "rtl.h"
27 #include "predict.h"
28 #include "basic-block.h"
29 #include "valtrack.h"
30 #include "hashtab.h"
31 #include "hash-set.h"
32 #include "vec.h"
33 #include "machmode.h"
34 #include "hard-reg-set.h"
35 #include "input.h"
36 #include "function.h"
37 #include "regs.h"
38 #include "emit-rtl.h"
40 /* gen_lowpart_no_emit hook implementation for DEBUG_INSNs. In DEBUG_INSNs,
41 all lowpart SUBREGs are valid, despite what the machine requires for
42 instructions. */
44 static rtx
45 gen_lowpart_for_debug (machine_mode mode, rtx x)
47 rtx result = gen_lowpart_if_possible (mode, x);
48 if (result)
49 return result;
51 if (GET_MODE (x) != VOIDmode)
52 return gen_rtx_raw_SUBREG (mode, x,
53 subreg_lowpart_offset (mode, GET_MODE (x)));
55 return NULL_RTX;
58 /* Replace auto-increment addressing modes with explicit operations to access
59 the same addresses without modifying the corresponding registers. */
61 static rtx
62 cleanup_auto_inc_dec (rtx src, machine_mode mem_mode ATTRIBUTE_UNUSED)
64 rtx x = src;
65 #ifdef AUTO_INC_DEC
66 const RTX_CODE code = GET_CODE (x);
67 int i;
68 const char *fmt;
70 switch (code)
72 case REG:
73 CASE_CONST_ANY:
74 case SYMBOL_REF:
75 case CODE_LABEL:
76 case PC:
77 case CC0:
78 case SCRATCH:
79 /* SCRATCH must be shared because they represent distinct values. */
80 return x;
81 case CLOBBER:
82 /* Share clobbers of hard registers (like cc0), but do not share pseudo reg
83 clobbers or clobbers of hard registers that originated as pseudos.
84 This is needed to allow safe register renaming. */
85 if (REG_P (XEXP (x, 0)) && REGNO (XEXP (x, 0)) < FIRST_PSEUDO_REGISTER
86 && ORIGINAL_REGNO (XEXP (x, 0)) == REGNO (XEXP (x, 0)))
87 return x;
88 break;
90 case CONST:
91 if (shared_const_p (x))
92 return x;
93 break;
95 case MEM:
96 mem_mode = GET_MODE (x);
97 break;
99 case PRE_INC:
100 case PRE_DEC:
101 gcc_assert (mem_mode != VOIDmode && mem_mode != BLKmode);
102 return gen_rtx_PLUS (GET_MODE (x),
103 cleanup_auto_inc_dec (XEXP (x, 0), mem_mode),
104 gen_int_mode (code == PRE_INC
105 ? GET_MODE_SIZE (mem_mode)
106 : -GET_MODE_SIZE (mem_mode),
107 GET_MODE (x)));
109 case POST_INC:
110 case POST_DEC:
111 case PRE_MODIFY:
112 case POST_MODIFY:
113 return cleanup_auto_inc_dec (code == PRE_MODIFY
114 ? XEXP (x, 1) : XEXP (x, 0),
115 mem_mode);
117 default:
118 break;
121 /* Copy the various flags, fields, and other information. We assume
122 that all fields need copying, and then clear the fields that should
123 not be copied. That is the sensible default behavior, and forces
124 us to explicitly document why we are *not* copying a flag. */
125 x = shallow_copy_rtx (x);
127 /* We do not copy the USED flag, which is used as a mark bit during
128 walks over the RTL. */
129 RTX_FLAG (x, used) = 0;
131 /* We do not copy FRAME_RELATED for INSNs. */
132 if (INSN_P (x))
133 RTX_FLAG (x, frame_related) = 0;
135 fmt = GET_RTX_FORMAT (code);
136 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
137 if (fmt[i] == 'e')
138 XEXP (x, i) = cleanup_auto_inc_dec (XEXP (x, i), mem_mode);
139 else if (fmt[i] == 'E' || fmt[i] == 'V')
141 int j;
142 XVEC (x, i) = rtvec_alloc (XVECLEN (x, i));
143 for (j = 0; j < XVECLEN (x, i); j++)
144 XVECEXP (x, i, j)
145 = cleanup_auto_inc_dec (XVECEXP (src, i, j), mem_mode);
148 #else /* !AUTO_INC_DEC */
149 x = copy_rtx (x);
150 #endif /* !AUTO_INC_DEC */
152 return x;
155 /* Auxiliary data structure for propagate_for_debug_stmt. */
157 struct rtx_subst_pair
159 rtx to;
160 bool adjusted;
163 /* DATA points to an rtx_subst_pair. Return the value that should be
164 substituted. */
166 static rtx
167 propagate_for_debug_subst (rtx from, const_rtx old_rtx, void *data)
169 struct rtx_subst_pair *pair = (struct rtx_subst_pair *)data;
171 if (!rtx_equal_p (from, old_rtx))
172 return NULL_RTX;
173 if (!pair->adjusted)
175 pair->adjusted = true;
176 pair->to = cleanup_auto_inc_dec (pair->to, VOIDmode);
177 pair->to = make_compound_operation (pair->to, SET);
178 return pair->to;
180 return copy_rtx (pair->to);
183 /* Replace all the occurrences of DEST with SRC in DEBUG_INSNs between INSN
184 and LAST, not including INSN, but including LAST. Also stop at the end
185 of THIS_BASIC_BLOCK. */
187 void
188 propagate_for_debug (rtx_insn *insn, rtx_insn *last, rtx dest, rtx src,
189 basic_block this_basic_block)
191 rtx_insn *next, *end = NEXT_INSN (BB_END (this_basic_block));
192 rtx loc;
193 rtx (*saved_rtl_hook_no_emit) (machine_mode, rtx);
195 struct rtx_subst_pair p;
196 p.to = src;
197 p.adjusted = false;
199 next = NEXT_INSN (insn);
200 last = NEXT_INSN (last);
201 saved_rtl_hook_no_emit = rtl_hooks.gen_lowpart_no_emit;
202 rtl_hooks.gen_lowpart_no_emit = gen_lowpart_for_debug;
203 while (next != last && next != end)
205 insn = next;
206 next = NEXT_INSN (insn);
207 if (DEBUG_INSN_P (insn))
209 loc = simplify_replace_fn_rtx (INSN_VAR_LOCATION_LOC (insn),
210 dest, propagate_for_debug_subst, &p);
211 if (loc == INSN_VAR_LOCATION_LOC (insn))
212 continue;
213 INSN_VAR_LOCATION_LOC (insn) = loc;
214 df_insn_rescan (insn);
217 rtl_hooks.gen_lowpart_no_emit = saved_rtl_hook_no_emit;
220 /* Initialize DEBUG to an empty list, and clear USED, if given. */
222 void
223 dead_debug_global_init (struct dead_debug_global *debug, bitmap used)
225 debug->used = used;
226 debug->htab = NULL;
227 if (used)
228 bitmap_clear (used);
231 /* Initialize DEBUG to an empty list, and clear USED, if given. Link
232 back to GLOBAL, if given, and bring in used bits from it. */
234 void
235 dead_debug_local_init (struct dead_debug_local *debug, bitmap used,
236 struct dead_debug_global *global)
238 if (!used && global && global->used)
239 used = BITMAP_ALLOC (NULL);
241 debug->head = NULL;
242 debug->global = global;
243 debug->used = used;
244 debug->to_rescan = NULL;
246 if (used)
248 if (global && global->used)
249 bitmap_copy (used, global->used);
250 else
251 bitmap_clear (used);
255 /* Locate the entry for REG in GLOBAL->htab. */
257 static dead_debug_global_entry *
258 dead_debug_global_find (struct dead_debug_global *global, rtx reg)
260 dead_debug_global_entry temp_entry;
261 temp_entry.reg = reg;
263 dead_debug_global_entry *entry = global->htab->find (&temp_entry);
264 gcc_checking_assert (entry && entry->reg == temp_entry.reg);
266 return entry;
269 /* Insert an entry mapping REG to DTEMP in GLOBAL->htab. */
271 static dead_debug_global_entry *
272 dead_debug_global_insert (struct dead_debug_global *global, rtx reg, rtx dtemp)
274 dead_debug_global_entry temp_entry;
275 temp_entry.reg = reg;
276 temp_entry.dtemp = dtemp;
278 if (!global->htab)
279 global->htab = new hash_table<dead_debug_hash_descr> (31);
281 dead_debug_global_entry **slot = global->htab->find_slot (&temp_entry,
282 INSERT);
283 gcc_checking_assert (!*slot);
284 *slot = XNEW (dead_debug_global_entry);
285 **slot = temp_entry;
286 return *slot;
289 /* If UREGNO, referenced by USE, is a pseudo marked as used in GLOBAL,
290 replace it with with a USE of the debug temp recorded for it, and
291 return TRUE. Otherwise, just return FALSE.
293 If PTO_RESCAN is given, instead of rescanning modified INSNs right
294 away, add their UIDs to the bitmap, allocating one of *PTO_RESCAN
295 is NULL. */
297 static bool
298 dead_debug_global_replace_temp (struct dead_debug_global *global,
299 df_ref use, unsigned int uregno,
300 bitmap *pto_rescan)
302 if (!global || uregno < FIRST_PSEUDO_REGISTER
303 || !global->used
304 || !REG_P (*DF_REF_REAL_LOC (use))
305 || REGNO (*DF_REF_REAL_LOC (use)) != uregno
306 || !bitmap_bit_p (global->used, uregno))
307 return false;
309 dead_debug_global_entry *entry
310 = dead_debug_global_find (global, *DF_REF_REAL_LOC (use));
311 gcc_checking_assert (GET_CODE (entry->reg) == REG
312 && REGNO (entry->reg) == uregno);
314 if (!entry->dtemp)
315 return true;
317 *DF_REF_REAL_LOC (use) = entry->dtemp;
318 if (!pto_rescan)
319 df_insn_rescan (DF_REF_INSN (use));
320 else
322 if (!*pto_rescan)
323 *pto_rescan = BITMAP_ALLOC (NULL);
324 bitmap_set_bit (*pto_rescan, INSN_UID (DF_REF_INSN (use)));
327 return true;
330 /* Reset all debug uses in HEAD, and clear DEBUG->to_rescan bits of
331 each reset insn. DEBUG is not otherwise modified. If HEAD is
332 DEBUG->head, DEBUG->head will be set to NULL at the end.
333 Otherwise, entries from DEBUG->head that pertain to reset insns
334 will be removed, and only then rescanned. */
336 static void
337 dead_debug_reset_uses (struct dead_debug_local *debug,
338 struct dead_debug_use *head)
340 bool got_head = (debug->head == head);
341 bitmap rescan;
342 struct dead_debug_use **tailp = &debug->head;
343 struct dead_debug_use *cur;
344 bitmap_iterator bi;
345 unsigned int uid;
347 if (got_head)
348 rescan = NULL;
349 else
350 rescan = BITMAP_ALLOC (NULL);
352 while (head)
354 struct dead_debug_use *next = head->next;
355 rtx_insn *insn;
357 insn = DF_REF_INSN (head->use);
358 if (!next || DF_REF_INSN (next->use) != insn)
360 INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC ();
361 if (got_head)
362 df_insn_rescan_debug_internal (insn);
363 else
364 bitmap_set_bit (rescan, INSN_UID (insn));
365 if (debug->to_rescan)
366 bitmap_clear_bit (debug->to_rescan, INSN_UID (insn));
368 XDELETE (head);
369 head = next;
372 if (got_head)
374 debug->head = NULL;
375 return;
378 while ((cur = *tailp))
379 if (bitmap_bit_p (rescan, INSN_UID (DF_REF_INSN (cur->use))))
381 *tailp = cur->next;
382 XDELETE (cur);
384 else
385 tailp = &cur->next;
387 EXECUTE_IF_SET_IN_BITMAP (rescan, 0, uid, bi)
389 struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid);
390 if (insn_info)
391 df_insn_rescan_debug_internal (insn_info->insn);
394 BITMAP_FREE (rescan);
397 /* Promote pending local uses of pseudos in DEBUG to global
398 substitutions. Uses of non-pseudos are left alone for
399 resetting. */
401 static void
402 dead_debug_promote_uses (struct dead_debug_local *debug)
404 for (struct dead_debug_use *head = debug->head, **headp = &debug->head;
405 head; head = *headp)
407 rtx reg = *DF_REF_REAL_LOC (head->use);
408 df_ref ref;
409 dead_debug_global_entry *entry;
411 if (GET_CODE (reg) != REG
412 || REGNO (reg) < FIRST_PSEUDO_REGISTER)
414 headp = &head->next;
415 continue;
418 if (!debug->global->used)
419 debug->global->used = BITMAP_ALLOC (NULL);
421 bool added = bitmap_set_bit (debug->global->used, REGNO (reg));
422 gcc_checking_assert (added);
424 entry = dead_debug_global_insert (debug->global, reg,
425 make_debug_expr_from_rtl (reg));
427 gcc_checking_assert (entry->dtemp);
429 /* Tentatively remove the USE from the list. */
430 *headp = head->next;
432 if (!debug->to_rescan)
433 debug->to_rescan = BITMAP_ALLOC (NULL);
435 for (ref = DF_REG_USE_CHAIN (REGNO (reg)); ref;
436 ref = DF_REF_NEXT_REG (ref))
437 if (DEBUG_INSN_P (DF_REF_INSN (ref)))
439 if (!dead_debug_global_replace_temp (debug->global, ref,
440 REGNO (reg),
441 &debug->to_rescan))
443 rtx_insn *insn = DF_REF_INSN (ref);
444 INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC ();
445 bitmap_set_bit (debug->to_rescan, INSN_UID (insn));
449 for (ref = DF_REG_DEF_CHAIN (REGNO (reg)); ref;
450 ref = DF_REF_NEXT_REG (ref))
451 if (!dead_debug_insert_temp (debug, REGNO (reg), DF_REF_INSN (ref),
452 DEBUG_TEMP_BEFORE_WITH_VALUE))
454 rtx bind;
455 bind = gen_rtx_VAR_LOCATION (GET_MODE (reg),
456 DEBUG_EXPR_TREE_DECL (entry->dtemp),
457 gen_rtx_UNKNOWN_VAR_LOC (),
458 VAR_INIT_STATUS_INITIALIZED);
459 rtx_insn *insn = emit_debug_insn_before (bind, DF_REF_INSN (ref));
460 bitmap_set_bit (debug->to_rescan, INSN_UID (insn));
463 entry->dtemp = NULL;
464 XDELETE (head);
468 /* Reset all debug insns with pending uses. Release the bitmap in it,
469 unless it is USED. USED must be the same bitmap passed to
470 dead_debug_local_init. */
472 void
473 dead_debug_local_finish (struct dead_debug_local *debug, bitmap used)
475 if (debug->global)
476 dead_debug_promote_uses (debug);
478 if (debug->used != used)
479 BITMAP_FREE (debug->used);
481 dead_debug_reset_uses (debug, debug->head);
483 if (debug->to_rescan)
485 bitmap_iterator bi;
486 unsigned int uid;
488 EXECUTE_IF_SET_IN_BITMAP (debug->to_rescan, 0, uid, bi)
490 struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid);
491 if (insn_info)
492 df_insn_rescan (insn_info->insn);
494 BITMAP_FREE (debug->to_rescan);
498 /* Release GLOBAL->used unless it is the same as USED. Release the
499 mapping hash table if it was initialized. */
501 void
502 dead_debug_global_finish (struct dead_debug_global *global, bitmap used)
504 if (global->used != used)
505 BITMAP_FREE (global->used);
507 delete global->htab;
508 global->htab = NULL;
511 /* Add USE to DEBUG, or substitute it right away if it's a pseudo in
512 the global substitution list. USE must be a dead reference to
513 UREGNO in a debug insn. Create a bitmap for DEBUG as needed. */
515 void
516 dead_debug_add (struct dead_debug_local *debug, df_ref use, unsigned int uregno)
518 if (dead_debug_global_replace_temp (debug->global, use, uregno,
519 &debug->to_rescan))
520 return;
522 struct dead_debug_use *newddu = XNEW (struct dead_debug_use);
524 newddu->use = use;
525 newddu->next = debug->head;
526 debug->head = newddu;
528 if (!debug->used)
529 debug->used = BITMAP_ALLOC (NULL);
531 /* ??? If we dealt with split multi-registers below, we should set
532 all registers for the used mode in case of hardware
533 registers. */
534 bitmap_set_bit (debug->used, uregno);
537 /* Like lowpart_subreg, but if a subreg is not valid for machine, force
538 it anyway - for use in debug insns. */
540 static rtx
541 debug_lowpart_subreg (machine_mode outer_mode, rtx expr,
542 machine_mode inner_mode)
544 if (inner_mode == VOIDmode)
545 inner_mode = GET_MODE (expr);
546 int offset = subreg_lowpart_offset (outer_mode, inner_mode);
547 rtx ret = simplify_gen_subreg (outer_mode, expr, inner_mode, offset);
548 if (ret)
549 return ret;
550 return gen_rtx_raw_SUBREG (outer_mode, expr, offset);
553 /* If UREGNO is referenced by any entry in DEBUG, emit a debug insn
554 before or after INSN (depending on WHERE), that binds a (possibly
555 global) debug temp to the widest-mode use of UREGNO, if WHERE is
556 *_WITH_REG, or the value stored in UREGNO by INSN otherwise, and
557 replace all uses of UREGNO in DEBUG with uses of the debug temp.
558 INSN must be where UREGNO dies, if WHERE is *_BEFORE_*, or where it
559 is set otherwise. Return the number of debug insns emitted. */
562 dead_debug_insert_temp (struct dead_debug_local *debug, unsigned int uregno,
563 rtx_insn *insn, enum debug_temp_where where)
565 struct dead_debug_use **tailp = &debug->head;
566 struct dead_debug_use *cur;
567 struct dead_debug_use *uses = NULL;
568 struct dead_debug_use **usesp = &uses;
569 rtx reg = NULL_RTX;
570 rtx breg;
571 rtx dval = NULL_RTX;
572 rtx bind;
573 bool global;
575 if (!debug->used)
576 return 0;
578 global = (debug->global && debug->global->used
579 && bitmap_bit_p (debug->global->used, uregno));
581 if (!global && !bitmap_clear_bit (debug->used, uregno))
582 return 0;
584 /* Move all uses of uregno from debug->head to uses, setting mode to
585 the widest referenced mode. */
586 while ((cur = *tailp))
588 if (DF_REF_REGNO (cur->use) == uregno)
590 /* If this loc has been changed e.g. to debug_expr already
591 as part of a multi-register use, just drop it. */
592 if (!REG_P (*DF_REF_REAL_LOC (cur->use)))
594 *tailp = cur->next;
595 XDELETE (cur);
596 continue;
598 *usesp = cur;
599 usesp = &cur->next;
600 *tailp = cur->next;
601 cur->next = NULL;
602 if (!reg
603 || (GET_MODE_BITSIZE (GET_MODE (reg))
604 < GET_MODE_BITSIZE (GET_MODE (*DF_REF_REAL_LOC (cur->use)))))
605 reg = *DF_REF_REAL_LOC (cur->use);
607 else
608 tailp = &(*tailp)->next;
611 /* We may have dangling bits in debug->used for registers that were part
612 of a multi-register use, one component of which has been reset. */
613 if (reg == NULL)
615 gcc_checking_assert (!uses);
616 if (!global)
617 return 0;
620 if (global)
622 if (!reg)
623 reg = regno_reg_rtx[uregno];
624 dead_debug_global_entry *entry
625 = dead_debug_global_find (debug->global, reg);
626 gcc_checking_assert (entry->reg == reg);
627 dval = entry->dtemp;
628 if (!dval)
629 return 0;
632 gcc_checking_assert (uses || global);
634 breg = reg;
635 /* Recover the expression INSN stores in REG. */
636 if (where == DEBUG_TEMP_BEFORE_WITH_VALUE)
638 rtx set = single_set (insn);
639 rtx dest, src;
641 if (set)
643 dest = SET_DEST (set);
644 src = SET_SRC (set);
645 /* Lose if the REG-setting insn is a CALL. */
646 if (GET_CODE (src) == CALL)
648 while (uses)
650 cur = uses->next;
651 XDELETE (uses);
652 uses = cur;
654 return 0;
658 /* ??? Should we try to extract it from a PARALLEL? */
659 if (!set)
660 breg = NULL;
661 /* Cool, it's the same REG, we can use SRC. */
662 else if (dest == reg)
663 breg = cleanup_auto_inc_dec (src, VOIDmode);
664 else if (REG_P (dest))
666 /* Hmm... Something's fishy, we should be setting REG here. */
667 if (REGNO (dest) != REGNO (reg))
668 breg = NULL;
669 /* If we're not overwriting all the hardware registers that
670 setting REG in its mode would, we won't know what to bind
671 the debug temp to. ??? We could bind the debug_expr to a
672 CONCAT or PARALLEL with the split multi-registers, and
673 replace them as we found the corresponding sets. */
674 else if (REGNO (reg) < FIRST_PSEUDO_REGISTER
675 && (hard_regno_nregs[REGNO (reg)][GET_MODE (reg)]
676 != hard_regno_nregs[REGNO (reg)][GET_MODE (dest)]))
677 breg = NULL;
678 /* Ok, it's the same (hardware) REG, but with a different
679 mode, so SUBREG it. */
680 else
681 breg = debug_lowpart_subreg (GET_MODE (reg),
682 cleanup_auto_inc_dec (src, VOIDmode),
683 GET_MODE (dest));
685 else if (GET_CODE (dest) == SUBREG)
687 /* We should be setting REG here. Lose. */
688 if (REGNO (SUBREG_REG (dest)) != REGNO (reg))
689 breg = NULL;
690 /* Lose if we're setting something other than the lowpart of
691 REG. */
692 else if (!subreg_lowpart_p (dest))
693 breg = NULL;
694 /* If we're not overwriting all the hardware registers that
695 setting REG in its mode would, we won't know what to bind
696 the debug temp to. */
697 else if (REGNO (reg) < FIRST_PSEUDO_REGISTER
698 && (hard_regno_nregs[REGNO (reg)][GET_MODE (reg)]
699 != hard_regno_nregs[REGNO (reg)][GET_MODE (dest)]))
700 breg = NULL;
701 /* Yay, we can use SRC, just adjust its mode. */
702 else
703 breg = debug_lowpart_subreg (GET_MODE (reg),
704 cleanup_auto_inc_dec (src, VOIDmode),
705 GET_MODE (dest));
707 /* Oh well, we're out of luck. */
708 else
709 breg = NULL;
711 /* We couldn't figure out the value stored in REG, so reset all
712 of its pending debug uses. */
713 if (!breg)
715 dead_debug_reset_uses (debug, uses);
716 return 0;
720 /* If there's a single (debug) use of an otherwise unused REG, and
721 the debug use is not part of a larger expression, then it
722 probably doesn't make sense to introduce a new debug temp. */
723 if (where == DEBUG_TEMP_AFTER_WITH_REG && !uses->next)
725 rtx_insn *next = DF_REF_INSN (uses->use);
727 if (DEBUG_INSN_P (next) && reg == INSN_VAR_LOCATION_LOC (next))
729 XDELETE (uses);
730 return 0;
734 if (!global)
735 /* Create DEBUG_EXPR (and DEBUG_EXPR_DECL). */
736 dval = make_debug_expr_from_rtl (reg);
738 /* Emit a debug bind insn before the insn in which reg dies. */
739 bind = gen_rtx_VAR_LOCATION (GET_MODE (reg),
740 DEBUG_EXPR_TREE_DECL (dval), breg,
741 VAR_INIT_STATUS_INITIALIZED);
743 if (where == DEBUG_TEMP_AFTER_WITH_REG
744 || where == DEBUG_TEMP_AFTER_WITH_REG_FORCE)
745 bind = emit_debug_insn_after (bind, insn);
746 else
747 bind = emit_debug_insn_before (bind, insn);
748 if (debug->to_rescan == NULL)
749 debug->to_rescan = BITMAP_ALLOC (NULL);
750 bitmap_set_bit (debug->to_rescan, INSN_UID (bind));
752 /* Adjust all uses. */
753 while ((cur = uses))
755 if (GET_MODE (*DF_REF_REAL_LOC (cur->use)) == GET_MODE (reg))
756 *DF_REF_REAL_LOC (cur->use) = dval;
757 else
758 *DF_REF_REAL_LOC (cur->use)
759 = debug_lowpart_subreg (GET_MODE (*DF_REF_REAL_LOC (cur->use)), dval,
760 GET_MODE (dval));
761 /* ??? Should we simplify subreg of subreg? */
762 bitmap_set_bit (debug->to_rescan, INSN_UID (DF_REF_INSN (cur->use)));
763 uses = cur->next;
764 XDELETE (cur);
767 return 1;