1 /* Standard problems for dataflow support routines.
2 Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
3 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
4 Originally contributed by Michael P. Hayes
5 (m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com)
6 Major rewrite contributed by Danny Berlin (dberlin@dberlin.org)
7 and Kenneth Zadeck (zadeck@naturalbridge.com).
9 This file is part of GCC.
11 GCC is free software; you can redistribute it and/or modify it under
12 the terms of the GNU General Public License as published by the Free
13 Software Foundation; either version 3, or (at your option) any later
16 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
17 WARRANTY; without even the implied warranty of MERCHANTABILITY or
18 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
21 You should have received a copy of the GNU General Public License
22 along with GCC; see the file COPYING3. If not see
23 <http://www.gnu.org/licenses/>. */
27 #include "coretypes.h"
31 #include "insn-config.h"
36 #include "alloc-pool.h"
38 #include "hard-reg-set.h"
39 #include "basic-block.h"
49 /* Note that turning REG_DEAD_DEBUGGING on will cause
50 gcc.c-torture/unsorted/dump-noaddr.c to fail because it prints
51 addresses in the dumps. */
53 #define REG_DEAD_DEBUGGING
56 #define DF_SPARSE_THRESHOLD 32
58 static bitmap_head seen_in_block;
59 static bitmap_head seen_in_insn;
62 /*----------------------------------------------------------------------------
63 Public functions access functions for the dataflow problems.
64 ----------------------------------------------------------------------------*/
65 /* Get the live at out set for BB no matter what problem happens to be
66 defined. This function is used by the register allocators who
67 choose different dataflow problems depending on the optimization
71 df_get_live_out (basic_block bb)
76 return DF_LIVE_OUT (bb);
78 return DF_LR_OUT (bb);
81 /* Get the live at in set for BB no matter what problem happens to be
82 defined. This function is used by the register allocators who
83 choose different dataflow problems depending on the optimization
87 df_get_live_in (basic_block bb)
92 return DF_LIVE_IN (bb);
97 /*----------------------------------------------------------------------------
99 ----------------------------------------------------------------------------*/
101 /* Generic versions to get the void* version of the block info. Only
102 used inside the problem instance vectors. */
104 /* Dump a def-use or use-def chain for REF to FILE. */
107 df_chain_dump (struct df_link *link, FILE *file)
109 fprintf (file, "{ ");
110 for (; link; link = link->next)
112 fprintf (file, "%c%d(bb %d insn %d) ",
113 DF_REF_REG_DEF_P (link->ref)
115 : (DF_REF_FLAGS (link->ref) & DF_REF_IN_NOTE) ? 'e' : 'u',
116 DF_REF_ID (link->ref),
117 DF_REF_BBNO (link->ref),
118 DF_REF_IS_ARTIFICIAL (link->ref)
119 ? -1 : DF_REF_INSN_UID (link->ref));
125 /* Print some basic block info as part of df_dump. */
128 df_print_bb_index (basic_block bb, FILE *file)
133 fprintf (file, "\n( ");
134 FOR_EACH_EDGE (e, ei, bb->preds)
136 basic_block pred = e->src;
137 fprintf (file, "%d%s ", pred->index, e->flags & EDGE_EH ? "(EH)" : "");
139 fprintf (file, ")->[%d]->( ", bb->index);
140 FOR_EACH_EDGE (e, ei, bb->succs)
142 basic_block succ = e->dest;
143 fprintf (file, "%d%s ", succ->index, e->flags & EDGE_EH ? "(EH)" : "");
145 fprintf (file, ")\n");
149 /*----------------------------------------------------------------------------
152 Find the locations in the function where each definition site for a
153 pseudo reaches. In and out bitvectors are built for each basic
154 block. The id field in the ref is used to index into these sets.
155 See df.h for details.
156 ----------------------------------------------------------------------------*/
158 /* This problem plays a large number of games for the sake of
161 1) The order of the bits in the bitvectors. After the scanning
162 phase, all of the defs are sorted. All of the defs for the reg 0
163 are first, followed by all defs for reg 1 and so on.
165 2) There are two kill sets, one if the number of defs is less or
166 equal to DF_SPARSE_THRESHOLD and another if the number of defs is
169 <= : Data is built directly in the kill set.
171 > : One level of indirection is used to keep from generating long
172 strings of 1 bits in the kill sets. Bitvectors that are indexed
173 by the regnum are used to represent that there is a killing def
174 for the register. The confluence and transfer functions use
175 these along with the bitmap_clear_range call to remove ranges of
176 bits without actually generating a knockout vector.
178 The kill and sparse_kill and the dense_invalidated_by_call and
179 sparse_invalidated_by_call both play this game. */
181 /* Private data used to compute the solution for this problem. These
182 data structures are not accessible outside of this module. */
183 struct df_rd_problem_data
185 /* The set of defs to regs invalidated by call. */
186 bitmap_head sparse_invalidated_by_call;
187 /* The set of defs to regs invalidate by call for rd. */
188 bitmap_head dense_invalidated_by_call;
189 /* An obstack for the bitmaps we need for this problem. */
190 bitmap_obstack rd_bitmaps;
194 /* Free basic block info. */
197 df_rd_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
200 struct df_rd_bb_info *bb_info = (struct df_rd_bb_info *) vbb_info;
203 bitmap_clear (&bb_info->kill);
204 bitmap_clear (&bb_info->sparse_kill);
205 bitmap_clear (&bb_info->gen);
206 bitmap_clear (&bb_info->in);
207 bitmap_clear (&bb_info->out);
212 /* Allocate or reset bitmaps for DF_RD blocks. The solution bits are
213 not touched unless the block is new. */
216 df_rd_alloc (bitmap all_blocks)
218 unsigned int bb_index;
220 struct df_rd_problem_data *problem_data;
222 if (df_rd->problem_data)
224 problem_data = (struct df_rd_problem_data *) df_rd->problem_data;
225 bitmap_clear (&problem_data->sparse_invalidated_by_call);
226 bitmap_clear (&problem_data->dense_invalidated_by_call);
230 problem_data = XNEW (struct df_rd_problem_data);
231 df_rd->problem_data = problem_data;
233 bitmap_obstack_initialize (&problem_data->rd_bitmaps);
234 bitmap_initialize (&problem_data->sparse_invalidated_by_call,
235 &problem_data->rd_bitmaps);
236 bitmap_initialize (&problem_data->dense_invalidated_by_call,
237 &problem_data->rd_bitmaps);
240 df_grow_bb_info (df_rd);
242 /* Because of the clustering of all use sites for the same pseudo,
243 we have to process all of the blocks before doing the
246 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
248 struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index);
250 /* When bitmaps are already initialized, just clear them. */
251 if (bb_info->kill.obstack)
253 bitmap_clear (&bb_info->kill);
254 bitmap_clear (&bb_info->sparse_kill);
255 bitmap_clear (&bb_info->gen);
259 bitmap_initialize (&bb_info->kill, &problem_data->rd_bitmaps);
260 bitmap_initialize (&bb_info->sparse_kill, &problem_data->rd_bitmaps);
261 bitmap_initialize (&bb_info->gen, &problem_data->rd_bitmaps);
262 bitmap_initialize (&bb_info->in, &problem_data->rd_bitmaps);
263 bitmap_initialize (&bb_info->out, &problem_data->rd_bitmaps);
266 df_rd->optional_p = true;
270 /* Add the effect of the top artificial defs of BB to the reaching definitions
274 df_rd_simulate_artificial_defs_at_top (basic_block bb, bitmap local_rd)
276 int bb_index = bb->index;
278 for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
280 df_ref def = *def_rec;
281 if (DF_REF_FLAGS (def) & DF_REF_AT_TOP)
283 unsigned int dregno = DF_REF_REGNO (def);
284 if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL)))
285 bitmap_clear_range (local_rd,
286 DF_DEFS_BEGIN (dregno),
287 DF_DEFS_COUNT (dregno));
288 bitmap_set_bit (local_rd, DF_REF_ID (def));
293 /* Add the effect of the defs of INSN to the reaching definitions bitmap
297 df_rd_simulate_one_insn (basic_block bb ATTRIBUTE_UNUSED, rtx insn,
300 unsigned uid = INSN_UID (insn);
303 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
305 df_ref def = *def_rec;
306 unsigned int dregno = DF_REF_REGNO (def);
307 if ((!(df->changeable_flags & DF_NO_HARD_REGS))
308 || (dregno >= FIRST_PSEUDO_REGISTER))
310 if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL)))
311 bitmap_clear_range (local_rd,
312 DF_DEFS_BEGIN (dregno),
313 DF_DEFS_COUNT (dregno));
314 if (!(DF_REF_FLAGS (def)
315 & (DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER)))
316 bitmap_set_bit (local_rd, DF_REF_ID (def));
321 /* Process a list of DEFs for df_rd_bb_local_compute. This is a bit
322 more complicated than just simulating, because we must produce the
323 gen and kill sets and hence deal with the two possible representations
327 df_rd_bb_local_compute_process_def (struct df_rd_bb_info *bb_info,
333 df_ref def = *def_rec;
334 if (top_flag == (DF_REF_FLAGS (def) & DF_REF_AT_TOP))
336 unsigned int regno = DF_REF_REGNO (def);
337 unsigned int begin = DF_DEFS_BEGIN (regno);
338 unsigned int n_defs = DF_DEFS_COUNT (regno);
340 if ((!(df->changeable_flags & DF_NO_HARD_REGS))
341 || (regno >= FIRST_PSEUDO_REGISTER))
343 /* Only the last def(s) for a regno in the block has any
345 if (!bitmap_bit_p (&seen_in_block, regno))
347 /* The first def for regno in insn gets to knock out the
348 defs from other instructions. */
349 if ((!bitmap_bit_p (&seen_in_insn, regno))
350 /* If the def is to only part of the reg, it does
351 not kill the other defs that reach here. */
352 && (!(DF_REF_FLAGS (def) &
353 (DF_REF_PARTIAL | DF_REF_CONDITIONAL | DF_REF_MAY_CLOBBER))))
355 if (n_defs > DF_SPARSE_THRESHOLD)
357 bitmap_set_bit (&bb_info->sparse_kill, regno);
358 bitmap_clear_range(&bb_info->gen, begin, n_defs);
362 bitmap_set_range (&bb_info->kill, begin, n_defs);
363 bitmap_clear_range (&bb_info->gen, begin, n_defs);
367 bitmap_set_bit (&seen_in_insn, regno);
368 /* All defs for regno in the instruction may be put into
370 if (!(DF_REF_FLAGS (def)
371 & (DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER)))
372 bitmap_set_bit (&bb_info->gen, DF_REF_ID (def));
380 /* Compute local reaching def info for basic block BB. */
383 df_rd_bb_local_compute (unsigned int bb_index)
385 basic_block bb = BASIC_BLOCK (bb_index);
386 struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index);
389 bitmap_clear (&seen_in_block);
390 bitmap_clear (&seen_in_insn);
392 /* Artificials are only hard regs. */
393 if (!(df->changeable_flags & DF_NO_HARD_REGS))
394 df_rd_bb_local_compute_process_def (bb_info,
395 df_get_artificial_defs (bb_index),
398 FOR_BB_INSNS_REVERSE (bb, insn)
400 unsigned int uid = INSN_UID (insn);
405 df_rd_bb_local_compute_process_def (bb_info,
406 DF_INSN_UID_DEFS (uid), 0);
408 /* This complex dance with the two bitmaps is required because
409 instructions can assign twice to the same pseudo. This
410 generally happens with calls that will have one def for the
411 result and another def for the clobber. If only one vector
412 is used and the clobber goes first, the result will be
414 bitmap_ior_into (&seen_in_block, &seen_in_insn);
415 bitmap_clear (&seen_in_insn);
418 /* Process the artificial defs at the top of the block last since we
419 are going backwards through the block and these are logically at
421 if (!(df->changeable_flags & DF_NO_HARD_REGS))
422 df_rd_bb_local_compute_process_def (bb_info,
423 df_get_artificial_defs (bb_index),
428 /* Compute local reaching def info for each basic block within BLOCKS. */
431 df_rd_local_compute (bitmap all_blocks)
433 unsigned int bb_index;
436 struct df_rd_problem_data *problem_data
437 = (struct df_rd_problem_data *) df_rd->problem_data;
438 bitmap sparse_invalidated = &problem_data->sparse_invalidated_by_call;
439 bitmap dense_invalidated = &problem_data->dense_invalidated_by_call;
441 bitmap_initialize (&seen_in_block, &df_bitmap_obstack);
442 bitmap_initialize (&seen_in_insn, &df_bitmap_obstack);
444 df_maybe_reorganize_def_refs (DF_REF_ORDER_BY_REG);
446 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
448 df_rd_bb_local_compute (bb_index);
451 /* Set up the knockout bit vectors to be applied across EH_EDGES. */
452 EXECUTE_IF_SET_IN_BITMAP (regs_invalidated_by_call_regset, 0, regno, bi)
454 if (DF_DEFS_COUNT (regno) > DF_SPARSE_THRESHOLD)
455 bitmap_set_bit (sparse_invalidated, regno);
457 bitmap_set_range (dense_invalidated,
458 DF_DEFS_BEGIN (regno),
459 DF_DEFS_COUNT (regno));
462 bitmap_clear (&seen_in_block);
463 bitmap_clear (&seen_in_insn);
467 /* Initialize the solution bit vectors for problem. */
470 df_rd_init_solution (bitmap all_blocks)
472 unsigned int bb_index;
475 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
477 struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index);
479 bitmap_copy (&bb_info->out, &bb_info->gen);
480 bitmap_clear (&bb_info->in);
484 /* In of target gets or of out of source. */
487 df_rd_confluence_n (edge e)
489 bitmap op1 = &df_rd_get_bb_info (e->dest->index)->in;
490 bitmap op2 = &df_rd_get_bb_info (e->src->index)->out;
491 bool changed = false;
493 if (e->flags & EDGE_FAKE)
496 if (e->flags & EDGE_EH)
498 struct df_rd_problem_data *problem_data
499 = (struct df_rd_problem_data *) df_rd->problem_data;
500 bitmap sparse_invalidated = &problem_data->sparse_invalidated_by_call;
501 bitmap dense_invalidated = &problem_data->dense_invalidated_by_call;
506 bitmap_initialize (&tmp, &df_bitmap_obstack);
507 bitmap_copy (&tmp, op2);
508 bitmap_and_compl_into (&tmp, dense_invalidated);
510 EXECUTE_IF_SET_IN_BITMAP (sparse_invalidated, 0, regno, bi)
512 bitmap_clear_range (&tmp,
513 DF_DEFS_BEGIN (regno),
514 DF_DEFS_COUNT (regno));
516 changed |= bitmap_ior_into (op1, &tmp);
521 return bitmap_ior_into (op1, op2);
525 /* Transfer function. */
528 df_rd_transfer_function (int bb_index)
530 struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index);
533 bitmap in = &bb_info->in;
534 bitmap out = &bb_info->out;
535 bitmap gen = &bb_info->gen;
536 bitmap kill = &bb_info->kill;
537 bitmap sparse_kill = &bb_info->sparse_kill;
539 if (bitmap_empty_p (sparse_kill))
540 return bitmap_ior_and_compl (out, gen, in, kill);
543 struct df_rd_problem_data *problem_data;
544 bool changed = false;
547 /* Note that TMP is _not_ a temporary bitmap if we end up replacing
548 OUT with TMP. Therefore, allocate TMP in the RD bitmaps obstack. */
549 problem_data = (struct df_rd_problem_data *) df_rd->problem_data;
550 bitmap_initialize (&tmp, &problem_data->rd_bitmaps);
552 bitmap_copy (&tmp, in);
553 EXECUTE_IF_SET_IN_BITMAP (sparse_kill, 0, regno, bi)
555 bitmap_clear_range (&tmp,
556 DF_DEFS_BEGIN (regno),
557 DF_DEFS_COUNT (regno));
559 bitmap_and_compl_into (&tmp, kill);
560 bitmap_ior_into (&tmp, gen);
561 changed = !bitmap_equal_p (&tmp, out);
574 /* Free all storage associated with the problem. */
579 struct df_rd_problem_data *problem_data
580 = (struct df_rd_problem_data *) df_rd->problem_data;
584 bitmap_obstack_release (&problem_data->rd_bitmaps);
586 df_rd->block_info_size = 0;
587 free (df_rd->block_info);
588 df_rd->block_info = NULL;
589 free (df_rd->problem_data);
595 /* Debugging info. */
598 df_rd_start_dump (FILE *file)
600 struct df_rd_problem_data *problem_data
601 = (struct df_rd_problem_data *) df_rd->problem_data;
602 unsigned int m = DF_REG_SIZE(df);
605 if (!df_rd->block_info)
608 fprintf (file, ";; Reaching defs:\n\n");
610 fprintf (file, " sparse invalidated \t");
611 dump_bitmap (file, &problem_data->sparse_invalidated_by_call);
612 fprintf (file, " dense invalidated \t");
613 dump_bitmap (file, &problem_data->dense_invalidated_by_call);
615 for (regno = 0; regno < m; regno++)
616 if (DF_DEFS_COUNT (regno))
617 fprintf (file, "%d[%d,%d] ", regno,
618 DF_DEFS_BEGIN (regno),
619 DF_DEFS_COUNT (regno));
620 fprintf (file, "\n");
625 /* Debugging info at top of bb. */
628 df_rd_top_dump (basic_block bb, FILE *file)
630 struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb->index);
634 fprintf (file, ";; rd in \t(%d)\n", (int) bitmap_count_bits (&bb_info->in));
635 dump_bitmap (file, &bb_info->in);
636 fprintf (file, ";; rd gen \t(%d)\n", (int) bitmap_count_bits (&bb_info->gen));
637 dump_bitmap (file, &bb_info->gen);
638 fprintf (file, ";; rd kill\t(%d)\n", (int) bitmap_count_bits (&bb_info->kill));
639 dump_bitmap (file, &bb_info->kill);
643 /* Debugging info at top of bb. */
646 df_rd_bottom_dump (basic_block bb, FILE *file)
648 struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb->index);
652 fprintf (file, ";; rd out \t(%d)\n", (int) bitmap_count_bits (&bb_info->out));
653 dump_bitmap (file, &bb_info->out);
656 /* All of the information associated with every instance of the problem. */
658 static struct df_problem problem_RD =
660 DF_RD, /* Problem id. */
661 DF_FORWARD, /* Direction. */
662 df_rd_alloc, /* Allocate the problem specific data. */
663 NULL, /* Reset global information. */
664 df_rd_free_bb_info, /* Free basic block info. */
665 df_rd_local_compute, /* Local compute function. */
666 df_rd_init_solution, /* Init the solution specific data. */
667 df_worklist_dataflow, /* Worklist solver. */
668 NULL, /* Confluence operator 0. */
669 df_rd_confluence_n, /* Confluence operator n. */
670 df_rd_transfer_function, /* Transfer function. */
671 NULL, /* Finalize function. */
672 df_rd_free, /* Free all of the problem information. */
673 df_rd_free, /* Remove this problem from the stack of dataflow problems. */
674 df_rd_start_dump, /* Debugging. */
675 df_rd_top_dump, /* Debugging start block. */
676 df_rd_bottom_dump, /* Debugging end block. */
677 NULL, /* Incremental solution verify start. */
678 NULL, /* Incremental solution verify end. */
679 NULL, /* Dependent problem. */
680 sizeof (struct df_rd_bb_info),/* Size of entry of block_info array. */
681 TV_DF_RD, /* Timing variable. */
682 true /* Reset blocks on dropping out of blocks_to_analyze. */
687 /* Create a new RD instance and add it to the existing instance
691 df_rd_add_problem (void)
693 df_add_problem (&problem_RD);
698 /*----------------------------------------------------------------------------
701 Find the locations in the function where any use of a pseudo can
702 reach in the backwards direction. In and out bitvectors are built
703 for each basic block. The regno is used to index into these sets.
704 See df.h for details.
705 ----------------------------------------------------------------------------*/
707 /* Private data used to verify the solution for this problem. */
708 struct df_lr_problem_data
712 /* An obstack for the bitmaps we need for this problem. */
713 bitmap_obstack lr_bitmaps;
716 /* Free basic block info. */
719 df_lr_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
722 struct df_lr_bb_info *bb_info = (struct df_lr_bb_info *) vbb_info;
725 bitmap_clear (&bb_info->use);
726 bitmap_clear (&bb_info->def);
727 bitmap_clear (&bb_info->in);
728 bitmap_clear (&bb_info->out);
733 /* Allocate or reset bitmaps for DF_LR blocks. The solution bits are
734 not touched unless the block is new. */
737 df_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
739 unsigned int bb_index;
741 struct df_lr_problem_data *problem_data;
743 df_grow_bb_info (df_lr);
744 if (df_lr->problem_data)
745 problem_data = (struct df_lr_problem_data *) df_lr->problem_data;
748 problem_data = XNEW (struct df_lr_problem_data);
749 df_lr->problem_data = problem_data;
751 problem_data->out = NULL;
752 problem_data->in = NULL;
753 bitmap_obstack_initialize (&problem_data->lr_bitmaps);
756 EXECUTE_IF_SET_IN_BITMAP (df_lr->out_of_date_transfer_functions, 0, bb_index, bi)
758 struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index);
760 /* When bitmaps are already initialized, just clear them. */
761 if (bb_info->use.obstack)
763 bitmap_clear (&bb_info->def);
764 bitmap_clear (&bb_info->use);
768 bitmap_initialize (&bb_info->use, &problem_data->lr_bitmaps);
769 bitmap_initialize (&bb_info->def, &problem_data->lr_bitmaps);
770 bitmap_initialize (&bb_info->in, &problem_data->lr_bitmaps);
771 bitmap_initialize (&bb_info->out, &problem_data->lr_bitmaps);
775 df_lr->optional_p = false;
779 /* Reset the global solution for recalculation. */
782 df_lr_reset (bitmap all_blocks)
784 unsigned int bb_index;
787 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
789 struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index);
790 gcc_assert (bb_info);
791 bitmap_clear (&bb_info->in);
792 bitmap_clear (&bb_info->out);
797 /* Compute local live register info for basic block BB. */
800 df_lr_bb_local_compute (unsigned int bb_index)
802 basic_block bb = BASIC_BLOCK (bb_index);
803 struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index);
808 /* Process the registers set in an exception handler. */
809 for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
811 df_ref def = *def_rec;
812 if ((DF_REF_FLAGS (def) & DF_REF_AT_TOP) == 0)
814 unsigned int dregno = DF_REF_REGNO (def);
815 bitmap_set_bit (&bb_info->def, dregno);
816 bitmap_clear_bit (&bb_info->use, dregno);
820 /* Process the hardware registers that are always live. */
821 for (use_rec = df_get_artificial_uses (bb_index); *use_rec; use_rec++)
823 df_ref use = *use_rec;
824 /* Add use to set of uses in this BB. */
825 if ((DF_REF_FLAGS (use) & DF_REF_AT_TOP) == 0)
826 bitmap_set_bit (&bb_info->use, DF_REF_REGNO (use));
829 FOR_BB_INSNS_REVERSE (bb, insn)
831 unsigned int uid = INSN_UID (insn);
833 if (!NONDEBUG_INSN_P (insn))
836 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
838 df_ref def = *def_rec;
839 /* If the def is to only part of the reg, it does
840 not kill the other defs that reach here. */
841 if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL)))
843 unsigned int dregno = DF_REF_REGNO (def);
844 bitmap_set_bit (&bb_info->def, dregno);
845 bitmap_clear_bit (&bb_info->use, dregno);
849 for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
851 df_ref use = *use_rec;
852 /* Add use to set of uses in this BB. */
853 bitmap_set_bit (&bb_info->use, DF_REF_REGNO (use));
857 /* Process the registers set in an exception handler or the hard
858 frame pointer if this block is the target of a non local
860 for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
862 df_ref def = *def_rec;
863 if (DF_REF_FLAGS (def) & DF_REF_AT_TOP)
865 unsigned int dregno = DF_REF_REGNO (def);
866 bitmap_set_bit (&bb_info->def, dregno);
867 bitmap_clear_bit (&bb_info->use, dregno);
872 /* Process the uses that are live into an exception handler. */
873 for (use_rec = df_get_artificial_uses (bb_index); *use_rec; use_rec++)
875 df_ref use = *use_rec;
876 /* Add use to set of uses in this BB. */
877 if (DF_REF_FLAGS (use) & DF_REF_AT_TOP)
878 bitmap_set_bit (&bb_info->use, DF_REF_REGNO (use));
882 /* If the df_live problem is not defined, such as at -O0 and -O1, we
883 still need to keep the luids up to date. This is normally done
884 in the df_live problem since this problem has a forwards
887 df_recompute_luids (bb);
891 /* Compute local live register info for each basic block within BLOCKS. */
894 df_lr_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED)
896 unsigned int bb_index;
899 bitmap_clear (&df->hardware_regs_used);
901 /* The all-important stack pointer must always be live. */
902 bitmap_set_bit (&df->hardware_regs_used, STACK_POINTER_REGNUM);
904 /* Before reload, there are a few registers that must be forced
905 live everywhere -- which might not already be the case for
906 blocks within infinite loops. */
907 if (!reload_completed)
909 unsigned int pic_offset_table_regnum = PIC_OFFSET_TABLE_REGNUM;
910 /* Any reference to any pseudo before reload is a potential
911 reference of the frame pointer. */
912 bitmap_set_bit (&df->hardware_regs_used, FRAME_POINTER_REGNUM);
914 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
915 /* Pseudos with argument area equivalences may require
916 reloading via the argument pointer. */
917 if (fixed_regs[ARG_POINTER_REGNUM])
918 bitmap_set_bit (&df->hardware_regs_used, ARG_POINTER_REGNUM);
921 /* Any constant, or pseudo with constant equivalences, may
922 require reloading from memory using the pic register. */
923 if (pic_offset_table_regnum != INVALID_REGNUM
924 && fixed_regs[pic_offset_table_regnum])
925 bitmap_set_bit (&df->hardware_regs_used, pic_offset_table_regnum);
928 EXECUTE_IF_SET_IN_BITMAP (df_lr->out_of_date_transfer_functions, 0, bb_index, bi)
930 if (bb_index == EXIT_BLOCK)
932 /* The exit block is special for this problem and its bits are
933 computed from thin air. */
934 struct df_lr_bb_info *bb_info = df_lr_get_bb_info (EXIT_BLOCK);
935 bitmap_copy (&bb_info->use, df->exit_block_uses);
938 df_lr_bb_local_compute (bb_index);
941 bitmap_clear (df_lr->out_of_date_transfer_functions);
945 /* Initialize the solution vectors. */
948 df_lr_init (bitmap all_blocks)
950 unsigned int bb_index;
953 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
955 struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index);
956 bitmap_copy (&bb_info->in, &bb_info->use);
957 bitmap_clear (&bb_info->out);
962 /* Confluence function that processes infinite loops. This might be a
963 noreturn function that throws. And even if it isn't, getting the
964 unwind info right helps debugging. */
966 df_lr_confluence_0 (basic_block bb)
968 bitmap op1 = &df_lr_get_bb_info (bb->index)->out;
969 if (bb != EXIT_BLOCK_PTR)
970 bitmap_copy (op1, &df->hardware_regs_used);
974 /* Confluence function that ignores fake edges. */
977 df_lr_confluence_n (edge e)
979 bitmap op1 = &df_lr_get_bb_info (e->src->index)->out;
980 bitmap op2 = &df_lr_get_bb_info (e->dest->index)->in;
981 bool changed = false;
983 /* Call-clobbered registers die across exception and call edges. */
984 /* ??? Abnormal call edges ignored for the moment, as this gets
985 confused by sibling call edges, which crashes reg-stack. */
986 if (e->flags & EDGE_EH)
987 changed = bitmap_ior_and_compl_into (op1, op2, regs_invalidated_by_call_regset);
989 changed = bitmap_ior_into (op1, op2);
991 changed |= bitmap_ior_into (op1, &df->hardware_regs_used);
996 /* Transfer function. */
999 df_lr_transfer_function (int bb_index)
1001 struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index);
1002 bitmap in = &bb_info->in;
1003 bitmap out = &bb_info->out;
1004 bitmap use = &bb_info->use;
1005 bitmap def = &bb_info->def;
1007 return bitmap_ior_and_compl (in, use, out, def);
1011 /* Run the fast dce as a side effect of building LR. */
1014 df_lr_finalize (bitmap all_blocks)
1016 df_lr->solutions_dirty = false;
1017 if (df->changeable_flags & DF_LR_RUN_DCE)
1021 /* If dce deletes some instructions, we need to recompute the lr
1022 solution before proceeding further. The problem is that fast
1023 dce is a pessimestic dataflow algorithm. In the case where
1024 it deletes a statement S inside of a loop, the uses inside of
1025 S may not be deleted from the dataflow solution because they
1026 were carried around the loop. While it is conservatively
1027 correct to leave these extra bits, the standards of df
1028 require that we maintain the best possible (least fixed
1029 point) solution. The only way to do that is to redo the
1030 iteration from the beginning. See PR35805 for an
1032 if (df_lr->solutions_dirty)
1034 df_clear_flags (DF_LR_RUN_DCE);
1035 df_lr_alloc (all_blocks);
1036 df_lr_local_compute (all_blocks);
1037 df_worklist_dataflow (df_lr, all_blocks, df->postorder, df->n_blocks);
1038 df_lr_finalize (all_blocks);
1039 df_set_flags (DF_LR_RUN_DCE);
1045 /* Free all storage associated with the problem. */
1050 struct df_lr_problem_data *problem_data
1051 = (struct df_lr_problem_data *) df_lr->problem_data;
1052 if (df_lr->block_info)
1055 df_lr->block_info_size = 0;
1056 free (df_lr->block_info);
1057 df_lr->block_info = NULL;
1058 bitmap_obstack_release (&problem_data->lr_bitmaps);
1059 free (df_lr->problem_data);
1060 df_lr->problem_data = NULL;
1063 BITMAP_FREE (df_lr->out_of_date_transfer_functions);
1068 /* Debugging info at top of bb. */
1071 df_lr_top_dump (basic_block bb, FILE *file)
1073 struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb->index);
1074 struct df_lr_problem_data *problem_data;
1078 fprintf (file, ";; lr in \t");
1079 df_print_regset (file, &bb_info->in);
1080 if (df_lr->problem_data)
1082 problem_data = (struct df_lr_problem_data *)df_lr->problem_data;
1083 if (problem_data->in)
1085 fprintf (file, ";; old in \t");
1086 df_print_regset (file, &problem_data->in[bb->index]);
1089 fprintf (file, ";; lr use \t");
1090 df_print_regset (file, &bb_info->use);
1091 fprintf (file, ";; lr def \t");
1092 df_print_regset (file, &bb_info->def);
1096 /* Debugging info at bottom of bb. */
1099 df_lr_bottom_dump (basic_block bb, FILE *file)
1101 struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb->index);
1102 struct df_lr_problem_data *problem_data;
1106 fprintf (file, ";; lr out \t");
1107 df_print_regset (file, &bb_info->out);
1108 if (df_lr->problem_data)
1110 problem_data = (struct df_lr_problem_data *)df_lr->problem_data;
1111 if (problem_data->out)
1113 fprintf (file, ";; old out \t");
1114 df_print_regset (file, &problem_data->out[bb->index]);
1120 /* Build the datastructure to verify that the solution to the dataflow
1121 equations is not dirty. */
1124 df_lr_verify_solution_start (void)
1127 struct df_lr_problem_data *problem_data;
1128 if (df_lr->solutions_dirty)
1131 /* Set it true so that the solution is recomputed. */
1132 df_lr->solutions_dirty = true;
1134 problem_data = (struct df_lr_problem_data *)df_lr->problem_data;
1135 problem_data->in = XNEWVEC (bitmap_head, last_basic_block);
1136 problem_data->out = XNEWVEC (bitmap_head, last_basic_block);
1140 bitmap_initialize (&problem_data->in[bb->index], &problem_data->lr_bitmaps);
1141 bitmap_initialize (&problem_data->out[bb->index], &problem_data->lr_bitmaps);
1142 bitmap_copy (&problem_data->in[bb->index], DF_LR_IN (bb));
1143 bitmap_copy (&problem_data->out[bb->index], DF_LR_OUT (bb));
1148 /* Compare the saved datastructure and the new solution to the dataflow
1152 df_lr_verify_solution_end (void)
1154 struct df_lr_problem_data *problem_data;
1157 problem_data = (struct df_lr_problem_data *)df_lr->problem_data;
1159 if (!problem_data->out)
1162 if (df_lr->solutions_dirty)
1163 /* Do not check if the solution is still dirty. See the comment
1164 in df_lr_finalize for details. */
1165 df_lr->solutions_dirty = false;
1169 if ((!bitmap_equal_p (&problem_data->in[bb->index], DF_LR_IN (bb)))
1170 || (!bitmap_equal_p (&problem_data->out[bb->index], DF_LR_OUT (bb))))
1172 /*df_dump (stderr);*/
1177 /* Cannot delete them immediately because you may want to dump them
1178 if the comparison fails. */
1181 bitmap_clear (&problem_data->in[bb->index]);
1182 bitmap_clear (&problem_data->out[bb->index]);
1185 free (problem_data->in);
1186 free (problem_data->out);
1187 problem_data->in = NULL;
1188 problem_data->out = NULL;
1192 /* All of the information associated with every instance of the problem. */
1194 static struct df_problem problem_LR =
1196 DF_LR, /* Problem id. */
1197 DF_BACKWARD, /* Direction. */
1198 df_lr_alloc, /* Allocate the problem specific data. */
1199 df_lr_reset, /* Reset global information. */
1200 df_lr_free_bb_info, /* Free basic block info. */
1201 df_lr_local_compute, /* Local compute function. */
1202 df_lr_init, /* Init the solution specific data. */
1203 df_worklist_dataflow, /* Worklist solver. */
1204 df_lr_confluence_0, /* Confluence operator 0. */
1205 df_lr_confluence_n, /* Confluence operator n. */
1206 df_lr_transfer_function, /* Transfer function. */
1207 df_lr_finalize, /* Finalize function. */
1208 df_lr_free, /* Free all of the problem information. */
1209 NULL, /* Remove this problem from the stack of dataflow problems. */
1210 NULL, /* Debugging. */
1211 df_lr_top_dump, /* Debugging start block. */
1212 df_lr_bottom_dump, /* Debugging end block. */
1213 df_lr_verify_solution_start,/* Incremental solution verify start. */
1214 df_lr_verify_solution_end, /* Incremental solution verify end. */
1215 NULL, /* Dependent problem. */
1216 sizeof (struct df_lr_bb_info),/* Size of entry of block_info array. */
1217 TV_DF_LR, /* Timing variable. */
1218 false /* Reset blocks on dropping out of blocks_to_analyze. */
1222 /* Create a new DATAFLOW instance and add it to an existing instance
1223 of DF. The returned structure is what is used to get at the
1227 df_lr_add_problem (void)
1229 df_add_problem (&problem_LR);
1230 /* These will be initialized when df_scan_blocks processes each
1232 df_lr->out_of_date_transfer_functions = BITMAP_ALLOC (NULL);
1236 /* Verify that all of the lr related info is consistent and
1240 df_lr_verify_transfer_functions (void)
1243 bitmap_head saved_def;
1244 bitmap_head saved_use;
1245 bitmap_head all_blocks;
1250 bitmap_initialize (&saved_def, &bitmap_default_obstack);
1251 bitmap_initialize (&saved_use, &bitmap_default_obstack);
1252 bitmap_initialize (&all_blocks, &bitmap_default_obstack);
1256 struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb->index);
1257 bitmap_set_bit (&all_blocks, bb->index);
1261 /* Make a copy of the transfer functions and then compute
1262 new ones to see if the transfer functions have
1264 if (!bitmap_bit_p (df_lr->out_of_date_transfer_functions,
1267 bitmap_copy (&saved_def, &bb_info->def);
1268 bitmap_copy (&saved_use, &bb_info->use);
1269 bitmap_clear (&bb_info->def);
1270 bitmap_clear (&bb_info->use);
1272 df_lr_bb_local_compute (bb->index);
1273 gcc_assert (bitmap_equal_p (&saved_def, &bb_info->def));
1274 gcc_assert (bitmap_equal_p (&saved_use, &bb_info->use));
1279 /* If we do not have basic block info, the block must be in
1280 the list of dirty blocks or else some one has added a
1281 block behind our backs. */
1282 gcc_assert (bitmap_bit_p (df_lr->out_of_date_transfer_functions,
1285 /* Make sure no one created a block without following
1287 gcc_assert (df_scan_get_bb_info (bb->index));
1290 /* Make sure there are no dirty bits in blocks that have been deleted. */
1291 gcc_assert (!bitmap_intersect_compl_p (df_lr->out_of_date_transfer_functions,
1294 bitmap_clear (&saved_def);
1295 bitmap_clear (&saved_use);
1296 bitmap_clear (&all_blocks);
1301 /*----------------------------------------------------------------------------
1302 LIVE AND MUST-INITIALIZED REGISTERS.
1304 This problem first computes the IN and OUT bitvectors for the
1305 must-initialized registers problems, which is a forward problem.
1306 It gives the set of registers for which we MUST have an available
1307 definition on any path from the entry block to the entry/exit of
1308 a basic block. Sets generate a definition, while clobbers kill
1311 In and out bitvectors are built for each basic block and are indexed by
1312 regnum (see df.h for details). In and out bitvectors in struct
1313 df_live_bb_info actually refers to the must-initialized problem;
1315 Then, the in and out sets for the LIVE problem itself are computed.
1316 These are the logical AND of the IN and OUT sets from the LR problem
1317 and the must-initialized problem.
1318 ----------------------------------------------------------------------------*/
1320 /* Private data used to verify the solution for this problem. */
1321 struct df_live_problem_data
1325 /* An obstack for the bitmaps we need for this problem. */
1326 bitmap_obstack live_bitmaps;
1329 /* Scratch var used by transfer functions. This is used to implement
1330 an optimization to reduce the amount of space used to compute the
1331 combined lr and live analysis. */
1332 static bitmap_head df_live_scratch;
1335 /* Free basic block info. */
1338 df_live_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
1341 struct df_live_bb_info *bb_info = (struct df_live_bb_info *) vbb_info;
1344 bitmap_clear (&bb_info->gen);
1345 bitmap_clear (&bb_info->kill);
1346 bitmap_clear (&bb_info->in);
1347 bitmap_clear (&bb_info->out);
1352 /* Allocate or reset bitmaps for DF_LIVE blocks. The solution bits are
1353 not touched unless the block is new. */
1356 df_live_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
1358 unsigned int bb_index;
1360 struct df_live_problem_data *problem_data;
1362 if (df_live->problem_data)
1363 problem_data = (struct df_live_problem_data *) df_live->problem_data;
1366 problem_data = XNEW (struct df_live_problem_data);
1367 df_live->problem_data = problem_data;
1369 problem_data->out = NULL;
1370 problem_data->in = NULL;
1371 bitmap_obstack_initialize (&problem_data->live_bitmaps);
1372 bitmap_initialize (&df_live_scratch, &problem_data->live_bitmaps);
1375 df_grow_bb_info (df_live);
1377 EXECUTE_IF_SET_IN_BITMAP (df_live->out_of_date_transfer_functions, 0, bb_index, bi)
1379 struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index);
1381 /* When bitmaps are already initialized, just clear them. */
1382 if (bb_info->kill.obstack)
1384 bitmap_clear (&bb_info->kill);
1385 bitmap_clear (&bb_info->gen);
1389 bitmap_initialize (&bb_info->kill, &problem_data->live_bitmaps);
1390 bitmap_initialize (&bb_info->gen, &problem_data->live_bitmaps);
1391 bitmap_initialize (&bb_info->in, &problem_data->live_bitmaps);
1392 bitmap_initialize (&bb_info->out, &problem_data->live_bitmaps);
1395 df_live->optional_p = (optimize <= 1);
1399 /* Reset the global solution for recalculation. */
1402 df_live_reset (bitmap all_blocks)
1404 unsigned int bb_index;
1407 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
1409 struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index);
1410 gcc_assert (bb_info);
1411 bitmap_clear (&bb_info->in);
1412 bitmap_clear (&bb_info->out);
1417 /* Compute local uninitialized register info for basic block BB. */
1420 df_live_bb_local_compute (unsigned int bb_index)
1422 basic_block bb = BASIC_BLOCK (bb_index);
1423 struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index);
1428 FOR_BB_INSNS (bb, insn)
1430 unsigned int uid = INSN_UID (insn);
1431 struct df_insn_info *insn_info = DF_INSN_UID_GET (uid);
1433 /* Inserting labels does not always trigger the incremental
1437 gcc_assert (!INSN_P (insn));
1438 insn_info = df_insn_create_insn_record (insn);
1441 DF_INSN_INFO_LUID (insn_info) = luid;
1446 for (def_rec = DF_INSN_INFO_DEFS (insn_info); *def_rec; def_rec++)
1448 df_ref def = *def_rec;
1449 unsigned int regno = DF_REF_REGNO (def);
1451 if (DF_REF_FLAGS_IS_SET (def,
1452 DF_REF_PARTIAL | DF_REF_CONDITIONAL))
1453 /* All partial or conditional def
1454 seen are included in the gen set. */
1455 bitmap_set_bit (&bb_info->gen, regno);
1456 else if (DF_REF_FLAGS_IS_SET (def, DF_REF_MUST_CLOBBER))
1457 /* Only must clobbers for the entire reg destroy the
1459 bitmap_set_bit (&bb_info->kill, regno);
1460 else if (! DF_REF_FLAGS_IS_SET (def, DF_REF_MAY_CLOBBER))
1461 bitmap_set_bit (&bb_info->gen, regno);
1465 for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
1467 df_ref def = *def_rec;
1468 bitmap_set_bit (&bb_info->gen, DF_REF_REGNO (def));
1473 /* Compute local uninitialized register info. */
1476 df_live_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED)
1478 unsigned int bb_index;
1481 df_grow_insn_info ();
1483 EXECUTE_IF_SET_IN_BITMAP (df_live->out_of_date_transfer_functions,
1486 df_live_bb_local_compute (bb_index);
1489 bitmap_clear (df_live->out_of_date_transfer_functions);
1493 /* Initialize the solution vectors. */
1496 df_live_init (bitmap all_blocks)
1498 unsigned int bb_index;
1501 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
1503 struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index);
1504 struct df_lr_bb_info *bb_lr_info = df_lr_get_bb_info (bb_index);
1506 /* No register may reach a location where it is not used. Thus
1507 we trim the rr result to the places where it is used. */
1508 bitmap_and (&bb_info->out, &bb_info->gen, &bb_lr_info->out);
1509 bitmap_clear (&bb_info->in);
1513 /* Forward confluence function that ignores fake edges. */
1516 df_live_confluence_n (edge e)
1518 bitmap op1 = &df_live_get_bb_info (e->dest->index)->in;
1519 bitmap op2 = &df_live_get_bb_info (e->src->index)->out;
1521 if (e->flags & EDGE_FAKE)
1524 return bitmap_ior_into (op1, op2);
1528 /* Transfer function for the forwards must-initialized problem. */
1531 df_live_transfer_function (int bb_index)
1533 struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index);
1534 struct df_lr_bb_info *bb_lr_info = df_lr_get_bb_info (bb_index);
1535 bitmap in = &bb_info->in;
1536 bitmap out = &bb_info->out;
1537 bitmap gen = &bb_info->gen;
1538 bitmap kill = &bb_info->kill;
1540 /* We need to use a scratch set here so that the value returned from this
1541 function invocation properly reflects whether the sets changed in a
1542 significant way; i.e. not just because the lr set was anded in. */
1543 bitmap_and (&df_live_scratch, gen, &bb_lr_info->out);
1544 /* No register may reach a location where it is not used. Thus
1545 we trim the rr result to the places where it is used. */
1546 bitmap_and_into (in, &bb_lr_info->in);
1548 return bitmap_ior_and_compl (out, &df_live_scratch, in, kill);
1552 /* And the LR info with the must-initialized registers, to produce the LIVE info. */
1555 df_live_finalize (bitmap all_blocks)
1558 if (df_live->solutions_dirty)
1561 unsigned int bb_index;
1563 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
1565 struct df_lr_bb_info *bb_lr_info = df_lr_get_bb_info (bb_index);
1566 struct df_live_bb_info *bb_live_info = df_live_get_bb_info (bb_index);
1568 /* No register may reach a location where it is not used. Thus
1569 we trim the rr result to the places where it is used. */
1570 bitmap_and_into (&bb_live_info->in, &bb_lr_info->in);
1571 bitmap_and_into (&bb_live_info->out, &bb_lr_info->out);
1574 df_live->solutions_dirty = false;
1579 /* Free all storage associated with the problem. */
1584 struct df_live_problem_data *problem_data
1585 = (struct df_live_problem_data *) df_live->problem_data;
1586 if (df_live->block_info)
1588 df_live->block_info_size = 0;
1589 free (df_live->block_info);
1590 df_live->block_info = NULL;
1591 bitmap_clear (&df_live_scratch);
1592 bitmap_obstack_release (&problem_data->live_bitmaps);
1593 free (problem_data);
1594 df_live->problem_data = NULL;
1596 BITMAP_FREE (df_live->out_of_date_transfer_functions);
1601 /* Debugging info at top of bb. */
1604 df_live_top_dump (basic_block bb, FILE *file)
1606 struct df_live_bb_info *bb_info = df_live_get_bb_info (bb->index);
1607 struct df_live_problem_data *problem_data;
1612 fprintf (file, ";; live in \t");
1613 df_print_regset (file, &bb_info->in);
1614 if (df_live->problem_data)
1616 problem_data = (struct df_live_problem_data *)df_live->problem_data;
1617 if (problem_data->in)
1619 fprintf (file, ";; old in \t");
1620 df_print_regset (file, &problem_data->in[bb->index]);
1623 fprintf (file, ";; live gen \t");
1624 df_print_regset (file, &bb_info->gen);
1625 fprintf (file, ";; live kill\t");
1626 df_print_regset (file, &bb_info->kill);
1630 /* Debugging info at bottom of bb. */
1633 df_live_bottom_dump (basic_block bb, FILE *file)
1635 struct df_live_bb_info *bb_info = df_live_get_bb_info (bb->index);
1636 struct df_live_problem_data *problem_data;
1641 fprintf (file, ";; live out \t");
1642 df_print_regset (file, &bb_info->out);
1643 if (df_live->problem_data)
1645 problem_data = (struct df_live_problem_data *)df_live->problem_data;
1646 if (problem_data->out)
1648 fprintf (file, ";; old out \t");
1649 df_print_regset (file, &problem_data->out[bb->index]);
1655 /* Build the datastructure to verify that the solution to the dataflow
1656 equations is not dirty. */
1659 df_live_verify_solution_start (void)
1662 struct df_live_problem_data *problem_data;
1663 if (df_live->solutions_dirty)
1666 /* Set it true so that the solution is recomputed. */
1667 df_live->solutions_dirty = true;
1669 problem_data = (struct df_live_problem_data *)df_live->problem_data;
1670 problem_data->in = XNEWVEC (bitmap_head, last_basic_block);
1671 problem_data->out = XNEWVEC (bitmap_head, last_basic_block);
1675 bitmap_initialize (&problem_data->in[bb->index], &problem_data->live_bitmaps);
1676 bitmap_initialize (&problem_data->out[bb->index], &problem_data->live_bitmaps);
1677 bitmap_copy (&problem_data->in[bb->index], DF_LIVE_IN (bb));
1678 bitmap_copy (&problem_data->out[bb->index], DF_LIVE_OUT (bb));
1683 /* Compare the saved datastructure and the new solution to the dataflow
1687 df_live_verify_solution_end (void)
1689 struct df_live_problem_data *problem_data;
1692 problem_data = (struct df_live_problem_data *)df_live->problem_data;
1693 if (!problem_data->out)
1698 if ((!bitmap_equal_p (&problem_data->in[bb->index], DF_LIVE_IN (bb)))
1699 || (!bitmap_equal_p (&problem_data->out[bb->index], DF_LIVE_OUT (bb))))
1701 /*df_dump (stderr);*/
1706 /* Cannot delete them immediately because you may want to dump them
1707 if the comparison fails. */
1710 bitmap_clear (&problem_data->in[bb->index]);
1711 bitmap_clear (&problem_data->out[bb->index]);
1714 free (problem_data->in);
1715 free (problem_data->out);
1716 free (problem_data);
1717 df_live->problem_data = NULL;
1721 /* All of the information associated with every instance of the problem. */
1723 static struct df_problem problem_LIVE =
1725 DF_LIVE, /* Problem id. */
1726 DF_FORWARD, /* Direction. */
1727 df_live_alloc, /* Allocate the problem specific data. */
1728 df_live_reset, /* Reset global information. */
1729 df_live_free_bb_info, /* Free basic block info. */
1730 df_live_local_compute, /* Local compute function. */
1731 df_live_init, /* Init the solution specific data. */
1732 df_worklist_dataflow, /* Worklist solver. */
1733 NULL, /* Confluence operator 0. */
1734 df_live_confluence_n, /* Confluence operator n. */
1735 df_live_transfer_function, /* Transfer function. */
1736 df_live_finalize, /* Finalize function. */
1737 df_live_free, /* Free all of the problem information. */
1738 df_live_free, /* Remove this problem from the stack of dataflow problems. */
1739 NULL, /* Debugging. */
1740 df_live_top_dump, /* Debugging start block. */
1741 df_live_bottom_dump, /* Debugging end block. */
1742 df_live_verify_solution_start,/* Incremental solution verify start. */
1743 df_live_verify_solution_end, /* Incremental solution verify end. */
1744 &problem_LR, /* Dependent problem. */
1745 sizeof (struct df_live_bb_info),/* Size of entry of block_info array. */
1746 TV_DF_LIVE, /* Timing variable. */
1747 false /* Reset blocks on dropping out of blocks_to_analyze. */
1751 /* Create a new DATAFLOW instance and add it to an existing instance
1752 of DF. The returned structure is what is used to get at the
1756 df_live_add_problem (void)
1758 df_add_problem (&problem_LIVE);
1759 /* These will be initialized when df_scan_blocks processes each
1761 df_live->out_of_date_transfer_functions = BITMAP_ALLOC (NULL);
1765 /* Set all of the blocks as dirty. This needs to be done if this
1766 problem is added after all of the insns have been scanned. */
1769 df_live_set_all_dirty (void)
1773 bitmap_set_bit (df_live->out_of_date_transfer_functions,
1778 /* Verify that all of the lr related info is consistent and
1782 df_live_verify_transfer_functions (void)
1785 bitmap_head saved_gen;
1786 bitmap_head saved_kill;
1787 bitmap_head all_blocks;
1792 bitmap_initialize (&saved_gen, &bitmap_default_obstack);
1793 bitmap_initialize (&saved_kill, &bitmap_default_obstack);
1794 bitmap_initialize (&all_blocks, &bitmap_default_obstack);
1796 df_grow_insn_info ();
1800 struct df_live_bb_info *bb_info = df_live_get_bb_info (bb->index);
1801 bitmap_set_bit (&all_blocks, bb->index);
1805 /* Make a copy of the transfer functions and then compute
1806 new ones to see if the transfer functions have
1808 if (!bitmap_bit_p (df_live->out_of_date_transfer_functions,
1811 bitmap_copy (&saved_gen, &bb_info->gen);
1812 bitmap_copy (&saved_kill, &bb_info->kill);
1813 bitmap_clear (&bb_info->gen);
1814 bitmap_clear (&bb_info->kill);
1816 df_live_bb_local_compute (bb->index);
1817 gcc_assert (bitmap_equal_p (&saved_gen, &bb_info->gen));
1818 gcc_assert (bitmap_equal_p (&saved_kill, &bb_info->kill));
1823 /* If we do not have basic block info, the block must be in
1824 the list of dirty blocks or else some one has added a
1825 block behind our backs. */
1826 gcc_assert (bitmap_bit_p (df_live->out_of_date_transfer_functions,
1829 /* Make sure no one created a block without following
1831 gcc_assert (df_scan_get_bb_info (bb->index));
1834 /* Make sure there are no dirty bits in blocks that have been deleted. */
1835 gcc_assert (!bitmap_intersect_compl_p (df_live->out_of_date_transfer_functions,
1837 bitmap_clear (&saved_gen);
1838 bitmap_clear (&saved_kill);
1839 bitmap_clear (&all_blocks);
1842 /*----------------------------------------------------------------------------
1843 CREATE DEF_USE (DU) and / or USE_DEF (UD) CHAINS
1845 Link either the defs to the uses and / or the uses to the defs.
1847 These problems are set up like the other dataflow problems so that
1848 they nicely fit into the framework. They are much simpler and only
1849 involve a single traversal of instructions and an examination of
1850 the reaching defs information (the dependent problem).
1851 ----------------------------------------------------------------------------*/
1853 #define df_chain_problem_p(FLAG) (((enum df_chain_flags)df_chain->local_flags)&(FLAG))
1855 /* Create a du or ud chain from SRC to DST and link it into SRC. */
1858 df_chain_create (df_ref src, df_ref dst)
1860 struct df_link *head = DF_REF_CHAIN (src);
1861 struct df_link *link = (struct df_link *) pool_alloc (df_chain->block_pool);
1863 DF_REF_CHAIN (src) = link;
1870 /* Delete any du or ud chains that start at REF and point to
1873 df_chain_unlink_1 (df_ref ref, df_ref target)
1875 struct df_link *chain = DF_REF_CHAIN (ref);
1876 struct df_link *prev = NULL;
1880 if (chain->ref == target)
1883 prev->next = chain->next;
1885 DF_REF_CHAIN (ref) = chain->next;
1886 pool_free (df_chain->block_pool, chain);
1890 chain = chain->next;
1895 /* Delete a du or ud chain that leave or point to REF. */
1898 df_chain_unlink (df_ref ref)
1900 struct df_link *chain = DF_REF_CHAIN (ref);
1903 struct df_link *next = chain->next;
1904 /* Delete the other side if it exists. */
1905 df_chain_unlink_1 (chain->ref, ref);
1906 pool_free (df_chain->block_pool, chain);
1909 DF_REF_CHAIN (ref) = NULL;
1913 /* Copy the du or ud chain starting at FROM_REF and attach it to
1917 df_chain_copy (df_ref to_ref,
1918 struct df_link *from_ref)
1922 df_chain_create (to_ref, from_ref->ref);
1923 from_ref = from_ref->next;
1928 /* Remove this problem from the stack of dataflow problems. */
1931 df_chain_remove_problem (void)
1934 unsigned int bb_index;
1936 /* Wholesale destruction of the old chains. */
1937 if (df_chain->block_pool)
1938 free_alloc_pool (df_chain->block_pool);
1940 EXECUTE_IF_SET_IN_BITMAP (df_chain->out_of_date_transfer_functions, 0, bb_index, bi)
1945 basic_block bb = BASIC_BLOCK (bb_index);
1947 if (df_chain_problem_p (DF_DU_CHAIN))
1948 for (def_rec = df_get_artificial_defs (bb->index); *def_rec; def_rec++)
1949 DF_REF_CHAIN (*def_rec) = NULL;
1950 if (df_chain_problem_p (DF_UD_CHAIN))
1951 for (use_rec = df_get_artificial_uses (bb->index); *use_rec; use_rec++)
1952 DF_REF_CHAIN (*use_rec) = NULL;
1954 FOR_BB_INSNS (bb, insn)
1956 unsigned int uid = INSN_UID (insn);
1960 if (df_chain_problem_p (DF_DU_CHAIN))
1961 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
1962 DF_REF_CHAIN (*def_rec) = NULL;
1963 if (df_chain_problem_p (DF_UD_CHAIN))
1965 for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
1966 DF_REF_CHAIN (*use_rec) = NULL;
1967 for (use_rec = DF_INSN_UID_EQ_USES (uid); *use_rec; use_rec++)
1968 DF_REF_CHAIN (*use_rec) = NULL;
1974 bitmap_clear (df_chain->out_of_date_transfer_functions);
1975 df_chain->block_pool = NULL;
1979 /* Remove the chain problem completely. */
1982 df_chain_fully_remove_problem (void)
1984 df_chain_remove_problem ();
1985 BITMAP_FREE (df_chain->out_of_date_transfer_functions);
1990 /* Create def-use or use-def chains. */
1993 df_chain_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
1995 df_chain_remove_problem ();
1996 df_chain->block_pool = create_alloc_pool ("df_chain_block pool",
1997 sizeof (struct df_link), 50);
1998 df_chain->optional_p = true;
2002 /* Reset all of the chains when the set of basic blocks changes. */
2005 df_chain_reset (bitmap blocks_to_clear ATTRIBUTE_UNUSED)
2007 df_chain_remove_problem ();
2011 /* Create the chains for a list of USEs. */
2014 df_chain_create_bb_process_use (bitmap local_rd,
2019 unsigned int def_index;
2023 df_ref use = *use_rec;
2024 unsigned int uregno = DF_REF_REGNO (use);
2025 if ((!(df->changeable_flags & DF_NO_HARD_REGS))
2026 || (uregno >= FIRST_PSEUDO_REGISTER))
2028 /* Do not want to go through this for an uninitialized var. */
2029 int count = DF_DEFS_COUNT (uregno);
2032 if (top_flag == (DF_REF_FLAGS (use) & DF_REF_AT_TOP))
2034 unsigned int first_index = DF_DEFS_BEGIN (uregno);
2035 unsigned int last_index = first_index + count - 1;
2037 EXECUTE_IF_SET_IN_BITMAP (local_rd, first_index, def_index, bi)
2040 if (def_index > last_index)
2043 def = DF_DEFS_GET (def_index);
2044 if (df_chain_problem_p (DF_DU_CHAIN))
2045 df_chain_create (def, use);
2046 if (df_chain_problem_p (DF_UD_CHAIN))
2047 df_chain_create (use, def);
2058 /* Create chains from reaching defs bitmaps for basic block BB. */
2061 df_chain_create_bb (unsigned int bb_index)
2063 basic_block bb = BASIC_BLOCK (bb_index);
2064 struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index);
2068 bitmap_initialize (&cpy, &bitmap_default_obstack);
2069 bitmap_copy (&cpy, &bb_info->in);
2070 bitmap_set_bit (df_chain->out_of_date_transfer_functions, bb_index);
2072 /* Since we are going forwards, process the artificial uses first
2073 then the artificial defs second. */
2076 /* Create the chains for the artificial uses from the EH_USES at the
2077 beginning of the block. */
2079 /* Artificials are only hard regs. */
2080 if (!(df->changeable_flags & DF_NO_HARD_REGS))
2081 df_chain_create_bb_process_use (&cpy,
2082 df_get_artificial_uses (bb->index),
2086 df_rd_simulate_artificial_defs_at_top (bb, &cpy);
2088 /* Process the regular instructions next. */
2089 FOR_BB_INSNS (bb, insn)
2092 unsigned int uid = INSN_UID (insn);
2094 /* First scan the uses and link them up with the defs that remain
2095 in the cpy vector. */
2096 df_chain_create_bb_process_use (&cpy, DF_INSN_UID_USES (uid), 0);
2097 if (df->changeable_flags & DF_EQ_NOTES)
2098 df_chain_create_bb_process_use (&cpy, DF_INSN_UID_EQ_USES (uid), 0);
2100 /* Since we are going forwards, process the defs second. */
2101 df_rd_simulate_one_insn (bb, insn, &cpy);
2104 /* Create the chains for the artificial uses of the hard registers
2105 at the end of the block. */
2106 if (!(df->changeable_flags & DF_NO_HARD_REGS))
2107 df_chain_create_bb_process_use (&cpy,
2108 df_get_artificial_uses (bb->index),
2111 bitmap_clear (&cpy);
2114 /* Create def-use chains from reaching use bitmaps for basic blocks
2118 df_chain_finalize (bitmap all_blocks)
2120 unsigned int bb_index;
2123 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
2125 df_chain_create_bb (bb_index);
2130 /* Free all storage associated with the problem. */
2133 df_chain_free (void)
2135 free_alloc_pool (df_chain->block_pool);
2136 BITMAP_FREE (df_chain->out_of_date_transfer_functions);
2141 /* Debugging info. */
2144 df_chain_top_dump (basic_block bb, FILE *file)
2146 if (df_chain_problem_p (DF_DU_CHAIN))
2149 df_ref *def_rec = df_get_artificial_defs (bb->index);
2153 fprintf (file, ";; DU chains for artificial defs\n");
2156 df_ref def = *def_rec;
2157 fprintf (file, ";; reg %d ", DF_REF_REGNO (def));
2158 df_chain_dump (DF_REF_CHAIN (def), file);
2159 fprintf (file, "\n");
2164 FOR_BB_INSNS (bb, insn)
2168 struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn);
2169 def_rec = DF_INSN_INFO_DEFS (insn_info);
2172 fprintf (file, ";; DU chains for insn luid %d uid %d\n",
2173 DF_INSN_INFO_LUID (insn_info), INSN_UID (insn));
2177 df_ref def = *def_rec;
2178 fprintf (file, ";; reg %d ", DF_REF_REGNO (def));
2179 if (DF_REF_FLAGS (def) & DF_REF_READ_WRITE)
2180 fprintf (file, "read/write ");
2181 df_chain_dump (DF_REF_CHAIN (def), file);
2182 fprintf (file, "\n");
2193 df_chain_bottom_dump (basic_block bb, FILE *file)
2195 if (df_chain_problem_p (DF_UD_CHAIN))
2198 df_ref *use_rec = df_get_artificial_uses (bb->index);
2202 fprintf (file, ";; UD chains for artificial uses\n");
2205 df_ref use = *use_rec;
2206 fprintf (file, ";; reg %d ", DF_REF_REGNO (use));
2207 df_chain_dump (DF_REF_CHAIN (use), file);
2208 fprintf (file, "\n");
2213 FOR_BB_INSNS (bb, insn)
2217 struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn);
2218 df_ref *eq_use_rec = DF_INSN_INFO_EQ_USES (insn_info);
2219 use_rec = DF_INSN_INFO_USES (insn_info);
2220 if (*use_rec || *eq_use_rec)
2222 fprintf (file, ";; UD chains for insn luid %d uid %d\n",
2223 DF_INSN_INFO_LUID (insn_info), INSN_UID (insn));
2227 df_ref use = *use_rec;
2228 fprintf (file, ";; reg %d ", DF_REF_REGNO (use));
2229 if (DF_REF_FLAGS (use) & DF_REF_READ_WRITE)
2230 fprintf (file, "read/write ");
2231 df_chain_dump (DF_REF_CHAIN (use), file);
2232 fprintf (file, "\n");
2237 df_ref use = *eq_use_rec;
2238 fprintf (file, ";; eq_note reg %d ", DF_REF_REGNO (use));
2239 df_chain_dump (DF_REF_CHAIN (use), file);
2240 fprintf (file, "\n");
2250 static struct df_problem problem_CHAIN =
2252 DF_CHAIN, /* Problem id. */
2253 DF_NONE, /* Direction. */
2254 df_chain_alloc, /* Allocate the problem specific data. */
2255 df_chain_reset, /* Reset global information. */
2256 NULL, /* Free basic block info. */
2257 NULL, /* Local compute function. */
2258 NULL, /* Init the solution specific data. */
2259 NULL, /* Iterative solver. */
2260 NULL, /* Confluence operator 0. */
2261 NULL, /* Confluence operator n. */
2262 NULL, /* Transfer function. */
2263 df_chain_finalize, /* Finalize function. */
2264 df_chain_free, /* Free all of the problem information. */
2265 df_chain_fully_remove_problem,/* Remove this problem from the stack of dataflow problems. */
2266 NULL, /* Debugging. */
2267 df_chain_top_dump, /* Debugging start block. */
2268 df_chain_bottom_dump, /* Debugging end block. */
2269 NULL, /* Incremental solution verify start. */
2270 NULL, /* Incremental solution verify end. */
2271 &problem_RD, /* Dependent problem. */
2272 sizeof (struct df_scan_bb_info),/* Size of entry of block_info array. */
2273 TV_DF_CHAIN, /* Timing variable. */
2274 false /* Reset blocks on dropping out of blocks_to_analyze. */
2278 /* Create a new DATAFLOW instance and add it to an existing instance
2279 of DF. The returned structure is what is used to get at the
2283 df_chain_add_problem (unsigned int chain_flags)
2285 df_add_problem (&problem_CHAIN);
2286 df_chain->local_flags = chain_flags;
2287 df_chain->out_of_date_transfer_functions = BITMAP_ALLOC (NULL);
2290 #undef df_chain_problem_p
2293 /*----------------------------------------------------------------------------
2294 WORD LEVEL LIVE REGISTERS
2296 Find the locations in the function where any use of a pseudo can
2297 reach in the backwards direction. In and out bitvectors are built
2298 for each basic block. We only track pseudo registers that have a
2299 size of 2 * UNITS_PER_WORD; bitmaps are indexed by 2 * regno and
2300 contain two bits corresponding to each of the subwords.
2302 ----------------------------------------------------------------------------*/
2304 /* Private data used to verify the solution for this problem. */
2305 struct df_word_lr_problem_data
2307 /* An obstack for the bitmaps we need for this problem. */
2308 bitmap_obstack word_lr_bitmaps;
2312 /* Free basic block info. */
2315 df_word_lr_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
2318 struct df_word_lr_bb_info *bb_info = (struct df_word_lr_bb_info *) vbb_info;
2321 bitmap_clear (&bb_info->use);
2322 bitmap_clear (&bb_info->def);
2323 bitmap_clear (&bb_info->in);
2324 bitmap_clear (&bb_info->out);
2329 /* Allocate or reset bitmaps for DF_WORD_LR blocks. The solution bits are
2330 not touched unless the block is new. */
2333 df_word_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
2335 unsigned int bb_index;
2338 struct df_word_lr_problem_data *problem_data
2339 = XNEW (struct df_word_lr_problem_data);
2341 df_word_lr->problem_data = problem_data;
2343 df_grow_bb_info (df_word_lr);
2345 /* Create the mapping from regnos to slots. This does not change
2346 unless the problem is destroyed and recreated. In particular, if
2347 we end up deleting the only insn that used a subreg, we do not
2348 want to redo the mapping because this would invalidate everything
2351 bitmap_obstack_initialize (&problem_data->word_lr_bitmaps);
2354 bitmap_set_bit (df_word_lr->out_of_date_transfer_functions, bb->index);
2356 bitmap_set_bit (df_word_lr->out_of_date_transfer_functions, ENTRY_BLOCK);
2357 bitmap_set_bit (df_word_lr->out_of_date_transfer_functions, EXIT_BLOCK);
2359 EXECUTE_IF_SET_IN_BITMAP (df_word_lr->out_of_date_transfer_functions, 0, bb_index, bi)
2361 struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb_index);
2363 /* When bitmaps are already initialized, just clear them. */
2364 if (bb_info->use.obstack)
2366 bitmap_clear (&bb_info->def);
2367 bitmap_clear (&bb_info->use);
2371 bitmap_initialize (&bb_info->use, &problem_data->word_lr_bitmaps);
2372 bitmap_initialize (&bb_info->def, &problem_data->word_lr_bitmaps);
2373 bitmap_initialize (&bb_info->in, &problem_data->word_lr_bitmaps);
2374 bitmap_initialize (&bb_info->out, &problem_data->word_lr_bitmaps);
2378 df_word_lr->optional_p = true;
2382 /* Reset the global solution for recalculation. */
2385 df_word_lr_reset (bitmap all_blocks)
2387 unsigned int bb_index;
2390 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
2392 struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb_index);
2393 gcc_assert (bb_info);
2394 bitmap_clear (&bb_info->in);
2395 bitmap_clear (&bb_info->out);
2399 /* Examine REF, and if it is for a reg we're interested in, set or
2400 clear the bits corresponding to its subwords from the bitmap
2401 according to IS_SET. LIVE is the bitmap we should update. We do
2402 not track hard regs or pseudos of any size other than 2 *
2404 We return true if we changed the bitmap, or if we encountered a register
2405 we're not tracking. */
2408 df_word_lr_mark_ref (df_ref ref, bool is_set, regset live)
2410 rtx orig_reg = DF_REF_REG (ref);
2412 enum machine_mode reg_mode;
2414 /* Left at -1 for whole accesses. */
2415 int which_subword = -1;
2416 bool changed = false;
2418 if (GET_CODE (reg) == SUBREG)
2419 reg = SUBREG_REG (orig_reg);
2420 regno = REGNO (reg);
2421 reg_mode = GET_MODE (reg);
2422 if (regno < FIRST_PSEUDO_REGISTER
2423 || GET_MODE_SIZE (reg_mode) != 2 * UNITS_PER_WORD)
2426 if (GET_CODE (orig_reg) == SUBREG
2427 && df_read_modify_subreg_p (orig_reg))
2429 gcc_assert (DF_REF_FLAGS_IS_SET (ref, DF_REF_PARTIAL));
2430 if (subreg_lowpart_p (orig_reg))
2437 if (which_subword != 1)
2438 changed |= bitmap_set_bit (live, regno * 2);
2439 if (which_subword != 0)
2440 changed |= bitmap_set_bit (live, regno * 2 + 1);
2444 if (which_subword != 1)
2445 changed |= bitmap_clear_bit (live, regno * 2);
2446 if (which_subword != 0)
2447 changed |= bitmap_clear_bit (live, regno * 2 + 1);
2452 /* Compute local live register info for basic block BB. */
2455 df_word_lr_bb_local_compute (unsigned int bb_index)
2457 basic_block bb = BASIC_BLOCK (bb_index);
2458 struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb_index);
2463 /* Ensure that artificial refs don't contain references to pseudos. */
2464 for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
2466 df_ref def = *def_rec;
2467 gcc_assert (DF_REF_REGNO (def) < FIRST_PSEUDO_REGISTER);
2470 for (use_rec = df_get_artificial_uses (bb_index); *use_rec; use_rec++)
2472 df_ref use = *use_rec;
2473 gcc_assert (DF_REF_REGNO (use) < FIRST_PSEUDO_REGISTER);
2476 FOR_BB_INSNS_REVERSE (bb, insn)
2478 unsigned int uid = INSN_UID (insn);
2480 if (!NONDEBUG_INSN_P (insn))
2482 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
2484 df_ref def = *def_rec;
2485 /* If the def is to only part of the reg, it does
2486 not kill the other defs that reach here. */
2487 if (!(DF_REF_FLAGS (def) & (DF_REF_CONDITIONAL)))
2489 df_word_lr_mark_ref (def, true, &bb_info->def);
2490 df_word_lr_mark_ref (def, false, &bb_info->use);
2493 for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
2495 df_ref use = *use_rec;
2496 df_word_lr_mark_ref (use, true, &bb_info->use);
2502 /* Compute local live register info for each basic block within BLOCKS. */
2505 df_word_lr_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED)
2507 unsigned int bb_index;
2510 EXECUTE_IF_SET_IN_BITMAP (df_word_lr->out_of_date_transfer_functions, 0, bb_index, bi)
2512 if (bb_index == EXIT_BLOCK)
2516 EXECUTE_IF_SET_IN_BITMAP (df->exit_block_uses, FIRST_PSEUDO_REGISTER,
2521 df_word_lr_bb_local_compute (bb_index);
2524 bitmap_clear (df_word_lr->out_of_date_transfer_functions);
2528 /* Initialize the solution vectors. */
2531 df_word_lr_init (bitmap all_blocks)
2533 unsigned int bb_index;
2536 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
2538 struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb_index);
2539 bitmap_copy (&bb_info->in, &bb_info->use);
2540 bitmap_clear (&bb_info->out);
2545 /* Confluence function that ignores fake edges. */
2548 df_word_lr_confluence_n (edge e)
2550 bitmap op1 = &df_word_lr_get_bb_info (e->src->index)->out;
2551 bitmap op2 = &df_word_lr_get_bb_info (e->dest->index)->in;
2553 return bitmap_ior_into (op1, op2);
2557 /* Transfer function. */
2560 df_word_lr_transfer_function (int bb_index)
2562 struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb_index);
2563 bitmap in = &bb_info->in;
2564 bitmap out = &bb_info->out;
2565 bitmap use = &bb_info->use;
2566 bitmap def = &bb_info->def;
2568 return bitmap_ior_and_compl (in, use, out, def);
2572 /* Free all storage associated with the problem. */
2575 df_word_lr_free (void)
2577 struct df_word_lr_problem_data *problem_data
2578 = (struct df_word_lr_problem_data *)df_word_lr->problem_data;
2580 if (df_word_lr->block_info)
2582 df_word_lr->block_info_size = 0;
2583 free (df_word_lr->block_info);
2584 df_word_lr->block_info = NULL;
2587 BITMAP_FREE (df_word_lr->out_of_date_transfer_functions);
2588 bitmap_obstack_release (&problem_data->word_lr_bitmaps);
2589 free (problem_data);
2594 /* Debugging info at top of bb. */
2597 df_word_lr_top_dump (basic_block bb, FILE *file)
2599 struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb->index);
2603 fprintf (file, ";; blr in \t");
2604 df_print_word_regset (file, &bb_info->in);
2605 fprintf (file, ";; blr use \t");
2606 df_print_word_regset (file, &bb_info->use);
2607 fprintf (file, ";; blr def \t");
2608 df_print_word_regset (file, &bb_info->def);
2612 /* Debugging info at bottom of bb. */
2615 df_word_lr_bottom_dump (basic_block bb, FILE *file)
2617 struct df_word_lr_bb_info *bb_info = df_word_lr_get_bb_info (bb->index);
2621 fprintf (file, ";; blr out \t");
2622 df_print_word_regset (file, &bb_info->out);
2626 /* All of the information associated with every instance of the problem. */
2628 static struct df_problem problem_WORD_LR =
2630 DF_WORD_LR, /* Problem id. */
2631 DF_BACKWARD, /* Direction. */
2632 df_word_lr_alloc, /* Allocate the problem specific data. */
2633 df_word_lr_reset, /* Reset global information. */
2634 df_word_lr_free_bb_info, /* Free basic block info. */
2635 df_word_lr_local_compute, /* Local compute function. */
2636 df_word_lr_init, /* Init the solution specific data. */
2637 df_worklist_dataflow, /* Worklist solver. */
2638 NULL, /* Confluence operator 0. */
2639 df_word_lr_confluence_n, /* Confluence operator n. */
2640 df_word_lr_transfer_function, /* Transfer function. */
2641 NULL, /* Finalize function. */
2642 df_word_lr_free, /* Free all of the problem information. */
2643 df_word_lr_free, /* Remove this problem from the stack of dataflow problems. */
2644 NULL, /* Debugging. */
2645 df_word_lr_top_dump, /* Debugging start block. */
2646 df_word_lr_bottom_dump, /* Debugging end block. */
2647 NULL, /* Incremental solution verify start. */
2648 NULL, /* Incremental solution verify end. */
2649 NULL, /* Dependent problem. */
2650 sizeof (struct df_word_lr_bb_info),/* Size of entry of block_info array. */
2651 TV_DF_WORD_LR, /* Timing variable. */
2652 false /* Reset blocks on dropping out of blocks_to_analyze. */
2656 /* Create a new DATAFLOW instance and add it to an existing instance
2657 of DF. The returned structure is what is used to get at the
2661 df_word_lr_add_problem (void)
2663 df_add_problem (&problem_WORD_LR);
2664 /* These will be initialized when df_scan_blocks processes each
2666 df_word_lr->out_of_date_transfer_functions = BITMAP_ALLOC (NULL);
2670 /* Simulate the effects of the defs of INSN on LIVE. Return true if we changed
2671 any bits, which is used by the caller to determine whether a set is
2672 necessary. We also return true if there are other reasons not to delete
2676 df_word_lr_simulate_defs (rtx insn, bitmap live)
2678 bool changed = false;
2680 unsigned int uid = INSN_UID (insn);
2682 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
2684 df_ref def = *def_rec;
2685 if (DF_REF_FLAGS (def) & DF_REF_CONDITIONAL)
2688 changed |= df_word_lr_mark_ref (*def_rec, false, live);
2694 /* Simulate the effects of the uses of INSN on LIVE. */
2697 df_word_lr_simulate_uses (rtx insn, bitmap live)
2700 unsigned int uid = INSN_UID (insn);
2702 for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
2703 df_word_lr_mark_ref (*use_rec, true, live);
2706 /*----------------------------------------------------------------------------
2707 This problem computes REG_DEAD and REG_UNUSED notes.
2708 ----------------------------------------------------------------------------*/
2711 df_note_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
2713 df_note->optional_p = true;
2716 #ifdef REG_DEAD_DEBUGGING
2718 df_print_note (const char *prefix, rtx insn, rtx note)
2722 fprintf (dump_file, "%s %d ", prefix, INSN_UID (insn));
2723 print_rtl (dump_file, note);
2724 fprintf (dump_file, "\n");
2730 /* After reg-stack, the x86 floating point stack regs are difficult to
2731 analyze because of all of the pushes, pops and rotations. Thus, we
2732 just leave the notes alone. */
2736 df_ignore_stack_reg (int regno)
2738 return regstack_completed
2739 && IN_RANGE (regno, FIRST_STACK_REG, LAST_STACK_REG);
2743 df_ignore_stack_reg (int regno ATTRIBUTE_UNUSED)
2750 /* Remove all of the REG_DEAD or REG_UNUSED notes from INSN and add
2751 them to OLD_DEAD_NOTES and OLD_UNUSED_NOTES. Remove also
2752 REG_EQUAL/REG_EQUIV notes referring to dead pseudos using LIVE
2753 as the bitmap of currently live registers. */
2756 df_kill_notes (rtx insn, bitmap live)
2758 rtx *pprev = ®_NOTES (insn);
2763 switch (REG_NOTE_KIND (link))
2766 /* After reg-stack, we need to ignore any unused notes
2767 for the stack registers. */
2768 if (df_ignore_stack_reg (REGNO (XEXP (link, 0))))
2770 pprev = &XEXP (link, 1);
2775 rtx next = XEXP (link, 1);
2776 #ifdef REG_DEAD_DEBUGGING
2777 df_print_note ("deleting: ", insn, link);
2779 free_EXPR_LIST_node (link);
2780 *pprev = link = next;
2785 /* After reg-stack, we need to ignore any unused notes
2786 for the stack registers. */
2787 if (df_ignore_stack_reg (REGNO (XEXP (link, 0))))
2789 pprev = &XEXP (link, 1);
2794 rtx next = XEXP (link, 1);
2795 #ifdef REG_DEAD_DEBUGGING
2796 df_print_note ("deleting: ", insn, link);
2798 free_EXPR_LIST_node (link);
2799 *pprev = link = next;
2806 /* Remove the notes that refer to dead registers. As we have at most
2807 one REG_EQUAL/EQUIV note, all of EQ_USES will refer to this note
2808 so we need to purge the complete EQ_USES vector when removing
2809 the note using df_notes_rescan. */
2811 bool deleted = false;
2813 for (use_rec = DF_INSN_EQ_USES (insn); *use_rec; use_rec++)
2815 df_ref use = *use_rec;
2816 if (DF_REF_REGNO (use) > FIRST_PSEUDO_REGISTER
2817 && (DF_REF_FLAGS (use) & DF_REF_IN_NOTE)
2818 && ! bitmap_bit_p (live, DF_REF_REGNO (use)))
2827 #ifdef REG_DEAD_DEBUGGING
2828 df_print_note ("deleting: ", insn, link);
2830 next = XEXP (link, 1);
2831 free_EXPR_LIST_node (link);
2832 *pprev = link = next;
2833 df_notes_rescan (insn);
2837 pprev = &XEXP (link, 1);
2843 pprev = &XEXP (link, 1);
2851 /* Set a NOTE_TYPE note for REG in INSN. */
2854 df_set_note (enum reg_note note_type, rtx insn, rtx reg)
2856 gcc_checking_assert (!DEBUG_INSN_P (insn));
2857 add_reg_note (insn, note_type, reg);
2860 /* A subroutine of df_set_unused_notes_for_mw, with a selection of its
2861 arguments. Return true if the register value described by MWS's
2862 mw_reg is known to be completely unused, and if mw_reg can therefore
2863 be used in a REG_UNUSED note. */
2866 df_whole_mw_reg_unused_p (struct df_mw_hardreg *mws,
2867 bitmap live, bitmap artificial_uses)
2871 /* If MWS describes a partial reference, create REG_UNUSED notes for
2872 individual hard registers. */
2873 if (mws->flags & DF_REF_PARTIAL)
2876 /* Likewise if some part of the register is used. */
2877 for (r = mws->start_regno; r <= mws->end_regno; r++)
2878 if (bitmap_bit_p (live, r)
2879 || bitmap_bit_p (artificial_uses, r))
2882 gcc_assert (REG_P (mws->mw_reg));
2887 /* Node of a linked list of uses of dead REGs in debug insns. */
2888 struct dead_debug_use
2891 struct dead_debug_use *next;
2894 /* Linked list of the above, with a bitmap of the REGs in the
2898 struct dead_debug_use *head;
2903 static void dead_debug_reset (struct dead_debug *, unsigned int);
2906 /* Set the REG_UNUSED notes for the multiword hardreg defs in INSN
2907 based on the bits in LIVE. Do not generate notes for registers in
2908 artificial uses. DO_NOT_GEN is updated so that REG_DEAD notes are
2909 not generated if the reg is both read and written by the
2914 df_set_unused_notes_for_mw (rtx insn, struct df_mw_hardreg *mws,
2915 bitmap live, bitmap do_not_gen,
2916 bitmap artificial_uses,
2917 struct dead_debug *debug)
2921 #ifdef REG_DEAD_DEBUGGING
2923 fprintf (dump_file, "mw_set_unused looking at mws[%d..%d]\n",
2924 mws->start_regno, mws->end_regno);
2927 if (df_whole_mw_reg_unused_p (mws, live, artificial_uses))
2929 unsigned int regno = mws->start_regno;
2930 df_set_note (REG_UNUSED, insn, mws->mw_reg);
2931 dead_debug_reset (debug, regno);
2933 #ifdef REG_DEAD_DEBUGGING
2934 df_print_note ("adding 1: ", insn, REG_NOTES (insn));
2936 bitmap_set_bit (do_not_gen, regno);
2937 /* Only do this if the value is totally dead. */
2940 for (r = mws->start_regno; r <= mws->end_regno; r++)
2942 if (!bitmap_bit_p (live, r)
2943 && !bitmap_bit_p (artificial_uses, r))
2945 df_set_note (REG_UNUSED, insn, regno_reg_rtx[r]);
2946 dead_debug_reset (debug, r);
2947 #ifdef REG_DEAD_DEBUGGING
2948 df_print_note ("adding 2: ", insn, REG_NOTES (insn));
2951 bitmap_set_bit (do_not_gen, r);
2956 /* A subroutine of df_set_dead_notes_for_mw, with a selection of its
2957 arguments. Return true if the register value described by MWS's
2958 mw_reg is known to be completely dead, and if mw_reg can therefore
2959 be used in a REG_DEAD note. */
2962 df_whole_mw_reg_dead_p (struct df_mw_hardreg *mws,
2963 bitmap live, bitmap artificial_uses,
2968 /* If MWS describes a partial reference, create REG_DEAD notes for
2969 individual hard registers. */
2970 if (mws->flags & DF_REF_PARTIAL)
2973 /* Likewise if some part of the register is not dead. */
2974 for (r = mws->start_regno; r <= mws->end_regno; r++)
2975 if (bitmap_bit_p (live, r)
2976 || bitmap_bit_p (artificial_uses, r)
2977 || bitmap_bit_p (do_not_gen, r))
2980 gcc_assert (REG_P (mws->mw_reg));
2984 /* Set the REG_DEAD notes for the multiword hardreg use in INSN based
2985 on the bits in LIVE. DO_NOT_GEN is used to keep REG_DEAD notes
2986 from being set if the instruction both reads and writes the
2990 df_set_dead_notes_for_mw (rtx insn, struct df_mw_hardreg *mws,
2991 bitmap live, bitmap do_not_gen,
2992 bitmap artificial_uses, bool *added_notes_p)
2995 bool is_debug = *added_notes_p;
2997 *added_notes_p = false;
2999 #ifdef REG_DEAD_DEBUGGING
3002 fprintf (dump_file, "mw_set_dead looking at mws[%d..%d]\n do_not_gen =",
3003 mws->start_regno, mws->end_regno);
3004 df_print_regset (dump_file, do_not_gen);
3005 fprintf (dump_file, " live =");
3006 df_print_regset (dump_file, live);
3007 fprintf (dump_file, " artificial uses =");
3008 df_print_regset (dump_file, artificial_uses);
3012 if (df_whole_mw_reg_dead_p (mws, live, artificial_uses, do_not_gen))
3014 /* Add a dead note for the entire multi word register. */
3017 *added_notes_p = true;
3020 df_set_note (REG_DEAD, insn, mws->mw_reg);
3021 #ifdef REG_DEAD_DEBUGGING
3022 df_print_note ("adding 1: ", insn, REG_NOTES (insn));
3027 for (r = mws->start_regno; r <= mws->end_regno; r++)
3028 if (!bitmap_bit_p (live, r)
3029 && !bitmap_bit_p (artificial_uses, r)
3030 && !bitmap_bit_p (do_not_gen, r))
3034 *added_notes_p = true;
3037 df_set_note (REG_DEAD, insn, regno_reg_rtx[r]);
3038 #ifdef REG_DEAD_DEBUGGING
3039 df_print_note ("adding 2: ", insn, REG_NOTES (insn));
3047 /* Create a REG_UNUSED note if necessary for DEF in INSN updating
3048 LIVE. Do not generate notes for registers in ARTIFICIAL_USES. */
3051 df_create_unused_note (rtx insn, df_ref def,
3052 bitmap live, bitmap artificial_uses,
3053 struct dead_debug *debug)
3055 unsigned int dregno = DF_REF_REGNO (def);
3057 #ifdef REG_DEAD_DEBUGGING
3060 fprintf (dump_file, " regular looking at def ");
3061 df_ref_debug (def, dump_file);
3065 if (!((DF_REF_FLAGS (def) & DF_REF_MW_HARDREG)
3066 || bitmap_bit_p (live, dregno)
3067 || bitmap_bit_p (artificial_uses, dregno)
3068 || df_ignore_stack_reg (dregno)))
3070 rtx reg = (DF_REF_LOC (def))
3071 ? *DF_REF_REAL_LOC (def): DF_REF_REG (def);
3072 df_set_note (REG_UNUSED, insn, reg);
3073 dead_debug_reset (debug, dregno);
3074 #ifdef REG_DEAD_DEBUGGING
3075 df_print_note ("adding 3: ", insn, REG_NOTES (insn));
3083 /* Initialize DEBUG to an empty list, and clear USED, if given. */
3085 dead_debug_init (struct dead_debug *debug, bitmap used)
3089 debug->to_rescan = NULL;
3091 bitmap_clear (used);
3094 /* Reset all debug insns with pending uses. Release the bitmap in it,
3095 unless it is USED. USED must be the same bitmap passed to
3098 dead_debug_finish (struct dead_debug *debug, bitmap used)
3100 struct dead_debug_use *head;
3103 if (debug->used != used)
3104 BITMAP_FREE (debug->used);
3106 while ((head = debug->head))
3108 insn = DF_REF_INSN (head->use);
3109 if (!head->next || DF_REF_INSN (head->next->use) != insn)
3111 INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC ();
3112 df_insn_rescan_debug_internal (insn);
3113 if (debug->to_rescan)
3114 bitmap_clear_bit (debug->to_rescan, INSN_UID (insn));
3116 debug->head = head->next;
3120 if (debug->to_rescan)
3125 EXECUTE_IF_SET_IN_BITMAP (debug->to_rescan, 0, uid, bi)
3127 struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid);
3129 df_insn_rescan (insn_info->insn);
3131 BITMAP_FREE (debug->to_rescan);
3135 /* Reset DEBUG_INSNs with pending uses of DREGNO. */
3137 dead_debug_reset (struct dead_debug *debug, unsigned int dregno)
3139 struct dead_debug_use **tailp = &debug->head;
3140 struct dead_debug_use **insnp = &debug->head;
3141 struct dead_debug_use *cur;
3144 if (!debug->used || !bitmap_clear_bit (debug->used, dregno))
3147 while ((cur = *tailp))
3149 if (DF_REF_REGNO (cur->use) == dregno)
3152 insn = DF_REF_INSN (cur->use);
3153 INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC ();
3154 if (debug->to_rescan == NULL)
3155 debug->to_rescan = BITMAP_ALLOC (NULL);
3156 bitmap_set_bit (debug->to_rescan, INSN_UID (insn));
3158 /* If the current use isn't the first one attached to INSN, go back
3159 to this first use. We assume that the uses attached to an insn
3161 if (tailp != insnp && DF_REF_INSN ((*insnp)->use) == insn)
3163 /* Then remove all the other uses attached to INSN. */
3164 while ((cur = *tailp) && DF_REF_INSN (cur->use) == insn)
3173 if (DF_REF_INSN ((*insnp)->use) != DF_REF_INSN (cur->use))
3175 tailp = &(*tailp)->next;
3180 /* Add USE to DEBUG. It must be a dead reference to UREGNO in a debug
3181 insn. Create a bitmap for DEBUG as needed. */
3183 dead_debug_add (struct dead_debug *debug, df_ref use, unsigned int uregno)
3185 struct dead_debug_use *newddu = XNEW (struct dead_debug_use);
3188 newddu->next = debug->head;
3189 debug->head = newddu;
3192 debug->used = BITMAP_ALLOC (NULL);
3194 bitmap_set_bit (debug->used, uregno);
3197 /* If UREGNO is referenced by any entry in DEBUG, emit a debug insn
3198 before INSN that binds the REG to a debug temp, and replace all
3199 uses of UREGNO in DEBUG with uses of the debug temp. INSN must be
3200 the insn where UREGNO dies. */
3202 dead_debug_insert_before (struct dead_debug *debug, unsigned int uregno,
3205 struct dead_debug_use **tailp = &debug->head;
3206 struct dead_debug_use *cur;
3207 struct dead_debug_use *uses = NULL;
3208 struct dead_debug_use **usesp = &uses;
3213 if (!debug->used || !bitmap_clear_bit (debug->used, uregno))
3216 /* Move all uses of uregno from debug->head to uses, setting mode to
3217 the widest referenced mode. */
3218 while ((cur = *tailp))
3220 if (DF_REF_REGNO (cur->use) == uregno)
3227 || (GET_MODE_BITSIZE (GET_MODE (reg))
3228 < GET_MODE_BITSIZE (GET_MODE (*DF_REF_REAL_LOC (cur->use)))))
3229 reg = *DF_REF_REAL_LOC (cur->use);
3232 tailp = &(*tailp)->next;
3235 /* We may have dangling bits in debug->used for registers that were part
3236 of a multi-register use, one component of which has been reset. */
3240 /* Create DEBUG_EXPR (and DEBUG_EXPR_DECL). */
3241 dval = make_debug_expr_from_rtl (reg);
3243 /* Emit a debug bind insn before the insn in which reg dies. */
3244 bind = gen_rtx_VAR_LOCATION (GET_MODE (reg),
3245 DEBUG_EXPR_TREE_DECL (dval), reg,
3246 VAR_INIT_STATUS_INITIALIZED);
3248 bind = emit_debug_insn_before (bind, insn);
3249 df_insn_rescan (bind);
3251 /* Adjust all uses. */
3252 while ((cur = uses))
3254 if (GET_MODE (*DF_REF_REAL_LOC (cur->use)) == GET_MODE (reg))
3255 *DF_REF_REAL_LOC (cur->use) = dval;
3257 *DF_REF_REAL_LOC (cur->use)
3258 = gen_lowpart_SUBREG (GET_MODE (*DF_REF_REAL_LOC (cur->use)), dval);
3259 /* ??? Should we simplify subreg of subreg? */
3260 if (debug->to_rescan == NULL)
3261 debug->to_rescan = BITMAP_ALLOC (NULL);
3262 bitmap_set_bit (debug->to_rescan, INSN_UID (DF_REF_INSN (cur->use)));
3268 /* Recompute the REG_DEAD and REG_UNUSED notes and compute register
3269 info: lifetime, bb, and number of defs and uses for basic block
3270 BB. The three bitvectors are scratch regs used here. */
3273 df_note_bb_compute (unsigned int bb_index,
3274 bitmap live, bitmap do_not_gen, bitmap artificial_uses)
3276 basic_block bb = BASIC_BLOCK (bb_index);
3280 struct dead_debug debug;
3282 dead_debug_init (&debug, NULL);
3284 bitmap_copy (live, df_get_live_out (bb));
3285 bitmap_clear (artificial_uses);
3287 #ifdef REG_DEAD_DEBUGGING
3290 fprintf (dump_file, "live at bottom ");
3291 df_print_regset (dump_file, live);
3295 /* Process the artificial defs and uses at the bottom of the block
3296 to begin processing. */
3297 for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
3299 df_ref def = *def_rec;
3300 #ifdef REG_DEAD_DEBUGGING
3302 fprintf (dump_file, "artificial def %d\n", DF_REF_REGNO (def));
3305 if ((DF_REF_FLAGS (def) & DF_REF_AT_TOP) == 0)
3306 bitmap_clear_bit (live, DF_REF_REGNO (def));
3309 for (use_rec = df_get_artificial_uses (bb_index); *use_rec; use_rec++)
3311 df_ref use = *use_rec;
3312 if ((DF_REF_FLAGS (use) & DF_REF_AT_TOP) == 0)
3314 unsigned int regno = DF_REF_REGNO (use);
3315 bitmap_set_bit (live, regno);
3317 /* Notes are not generated for any of the artificial registers
3318 at the bottom of the block. */
3319 bitmap_set_bit (artificial_uses, regno);
3323 #ifdef REG_DEAD_DEBUGGING
3326 fprintf (dump_file, "live before artificials out ");
3327 df_print_regset (dump_file, live);
3331 FOR_BB_INSNS_REVERSE (bb, insn)
3333 unsigned int uid = INSN_UID (insn);
3334 struct df_mw_hardreg **mws_rec;
3340 debug_insn = DEBUG_INSN_P (insn);
3342 bitmap_clear (do_not_gen);
3343 df_kill_notes (insn, live);
3345 /* Process the defs. */
3348 #ifdef REG_DEAD_DEBUGGING
3351 fprintf (dump_file, "processing call %d\n live =", INSN_UID (insn));
3352 df_print_regset (dump_file, live);
3355 /* We only care about real sets for calls. Clobbers cannot
3356 be depended on to really die. */
3357 mws_rec = DF_INSN_UID_MWS (uid);
3360 struct df_mw_hardreg *mws = *mws_rec;
3361 if ((DF_MWS_REG_DEF_P (mws))
3362 && !df_ignore_stack_reg (mws->start_regno))
3363 df_set_unused_notes_for_mw (insn,
3364 mws, live, do_not_gen,
3365 artificial_uses, &debug);
3369 /* All of the defs except the return value are some sort of
3370 clobber. This code is for the return. */
3371 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
3373 df_ref def = *def_rec;
3374 unsigned int dregno = DF_REF_REGNO (def);
3375 if (!DF_REF_FLAGS_IS_SET (def, DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER))
3377 df_create_unused_note (insn,
3378 def, live, artificial_uses, &debug);
3379 bitmap_set_bit (do_not_gen, dregno);
3382 if (!DF_REF_FLAGS_IS_SET (def, DF_REF_PARTIAL | DF_REF_CONDITIONAL))
3383 bitmap_clear_bit (live, dregno);
3389 mws_rec = DF_INSN_UID_MWS (uid);
3392 struct df_mw_hardreg *mws = *mws_rec;
3393 if (DF_MWS_REG_DEF_P (mws))
3394 df_set_unused_notes_for_mw (insn,
3395 mws, live, do_not_gen,
3396 artificial_uses, &debug);
3400 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
3402 df_ref def = *def_rec;
3403 unsigned int dregno = DF_REF_REGNO (def);
3404 df_create_unused_note (insn,
3405 def, live, artificial_uses, &debug);
3407 if (!DF_REF_FLAGS_IS_SET (def, DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER))
3408 bitmap_set_bit (do_not_gen, dregno);
3410 if (!DF_REF_FLAGS_IS_SET (def, DF_REF_PARTIAL | DF_REF_CONDITIONAL))
3411 bitmap_clear_bit (live, dregno);
3415 /* Process the uses. */
3416 mws_rec = DF_INSN_UID_MWS (uid);
3419 struct df_mw_hardreg *mws = *mws_rec;
3420 if (DF_MWS_REG_USE_P (mws)
3421 && !df_ignore_stack_reg (mws->start_regno))
3423 bool really_add_notes = debug_insn != 0;
3425 df_set_dead_notes_for_mw (insn,
3426 mws, live, do_not_gen,
3430 if (really_add_notes)
3436 for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
3438 df_ref use = *use_rec;
3439 unsigned int uregno = DF_REF_REGNO (use);
3441 #ifdef REG_DEAD_DEBUGGING
3442 if (dump_file && !debug_insn)
3444 fprintf (dump_file, " regular looking at use ");
3445 df_ref_debug (use, dump_file);
3448 if (!bitmap_bit_p (live, uregno))
3454 dead_debug_add (&debug, use, uregno);
3460 dead_debug_insert_before (&debug, uregno, insn);
3462 if ( (!(DF_REF_FLAGS (use)
3463 & (DF_REF_MW_HARDREG | DF_REF_READ_WRITE)))
3464 && (!bitmap_bit_p (do_not_gen, uregno))
3465 && (!bitmap_bit_p (artificial_uses, uregno))
3466 && (!df_ignore_stack_reg (uregno)))
3468 rtx reg = (DF_REF_LOC (use))
3469 ? *DF_REF_REAL_LOC (use) : DF_REF_REG (use);
3470 df_set_note (REG_DEAD, insn, reg);
3472 #ifdef REG_DEAD_DEBUGGING
3473 df_print_note ("adding 4: ", insn, REG_NOTES (insn));
3476 /* This register is now live. */
3477 bitmap_set_bit (live, uregno);
3481 if (debug_insn == -1)
3483 /* ??? We could probably do better here, replacing dead
3484 registers with their definitions. */
3485 INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC ();
3486 df_insn_rescan_debug_internal (insn);
3490 dead_debug_finish (&debug, NULL);
3494 /* Compute register info: lifetime, bb, and number of defs and uses. */
3496 df_note_compute (bitmap all_blocks)
3498 unsigned int bb_index;
3500 bitmap_head live, do_not_gen, artificial_uses;
3502 bitmap_initialize (&live, &df_bitmap_obstack);
3503 bitmap_initialize (&do_not_gen, &df_bitmap_obstack);
3504 bitmap_initialize (&artificial_uses, &df_bitmap_obstack);
3506 #ifdef REG_DEAD_DEBUGGING
3508 print_rtl_with_bb (dump_file, get_insns());
3511 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
3513 df_note_bb_compute (bb_index, &live, &do_not_gen, &artificial_uses);
3516 bitmap_clear (&live);
3517 bitmap_clear (&do_not_gen);
3518 bitmap_clear (&artificial_uses);
3522 /* Free all storage associated with the problem. */
3531 /* All of the information associated every instance of the problem. */
3533 static struct df_problem problem_NOTE =
3535 DF_NOTE, /* Problem id. */
3536 DF_NONE, /* Direction. */
3537 df_note_alloc, /* Allocate the problem specific data. */
3538 NULL, /* Reset global information. */
3539 NULL, /* Free basic block info. */
3540 df_note_compute, /* Local compute function. */
3541 NULL, /* Init the solution specific data. */
3542 NULL, /* Iterative solver. */
3543 NULL, /* Confluence operator 0. */
3544 NULL, /* Confluence operator n. */
3545 NULL, /* Transfer function. */
3546 NULL, /* Finalize function. */
3547 df_note_free, /* Free all of the problem information. */
3548 df_note_free, /* Remove this problem from the stack of dataflow problems. */
3549 NULL, /* Debugging. */
3550 NULL, /* Debugging start block. */
3551 NULL, /* Debugging end block. */
3552 NULL, /* Incremental solution verify start. */
3553 NULL, /* Incremental solution verify end. */
3554 &problem_LR, /* Dependent problem. */
3555 sizeof (struct df_scan_bb_info),/* Size of entry of block_info array. */
3556 TV_DF_NOTE, /* Timing variable. */
3557 false /* Reset blocks on dropping out of blocks_to_analyze. */
3561 /* Create a new DATAFLOW instance and add it to an existing instance
3562 of DF. The returned structure is what is used to get at the
3566 df_note_add_problem (void)
3568 df_add_problem (&problem_NOTE);
3574 /*----------------------------------------------------------------------------
3575 Functions for simulating the effects of single insns.
3577 You can either simulate in the forwards direction, starting from
3578 the top of a block or the backwards direction from the end of the
3579 block. If you go backwards, defs are examined first to clear bits,
3580 then uses are examined to set bits. If you go forwards, defs are
3581 examined first to set bits, then REG_DEAD and REG_UNUSED notes
3582 are examined to clear bits. In either case, the result of examining
3583 a def can be undone (respectively by a use or a REG_UNUSED note).
3585 If you start at the top of the block, use one of DF_LIVE_IN or
3586 DF_LR_IN. If you start at the bottom of the block use one of
3587 DF_LIVE_OUT or DF_LR_OUT. BE SURE TO PASS A COPY OF THESE SETS,
3588 THEY WILL BE DESTROYED.
3589 ----------------------------------------------------------------------------*/
3592 /* Find the set of DEFs for INSN. */
3595 df_simulate_find_defs (rtx insn, bitmap defs)
3598 unsigned int uid = INSN_UID (insn);
3600 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
3602 df_ref def = *def_rec;
3603 bitmap_set_bit (defs, DF_REF_REGNO (def));
3607 /* Find the set of uses for INSN. This includes partial defs. */
3610 df_simulate_find_uses (rtx insn, bitmap uses)
3613 unsigned int uid = INSN_UID (insn);
3615 for (rec = DF_INSN_UID_DEFS (uid); *rec; rec++)
3618 if (DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL))
3619 bitmap_set_bit (uses, DF_REF_REGNO (def));
3621 for (rec = DF_INSN_UID_USES (uid); *rec; rec++)
3624 bitmap_set_bit (uses, DF_REF_REGNO (use));
3628 /* Find the set of real DEFs, which are not clobbers, for INSN. */
3631 df_simulate_find_noclobber_defs (rtx insn, bitmap defs)
3634 unsigned int uid = INSN_UID (insn);
3636 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
3638 df_ref def = *def_rec;
3639 if (!(DF_REF_FLAGS (def) & (DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER)))
3640 bitmap_set_bit (defs, DF_REF_REGNO (def));
3645 /* Simulate the effects of the defs of INSN on LIVE. */
3648 df_simulate_defs (rtx insn, bitmap live)
3651 unsigned int uid = INSN_UID (insn);
3653 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
3655 df_ref def = *def_rec;
3656 unsigned int dregno = DF_REF_REGNO (def);
3658 /* If the def is to only part of the reg, it does
3659 not kill the other defs that reach here. */
3660 if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL)))
3661 bitmap_clear_bit (live, dregno);
3666 /* Simulate the effects of the uses of INSN on LIVE. */
3669 df_simulate_uses (rtx insn, bitmap live)
3672 unsigned int uid = INSN_UID (insn);
3674 if (DEBUG_INSN_P (insn))
3677 for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
3679 df_ref use = *use_rec;
3680 /* Add use to set of uses in this BB. */
3681 bitmap_set_bit (live, DF_REF_REGNO (use));
3686 /* Add back the always live regs in BB to LIVE. */
3689 df_simulate_fixup_sets (basic_block bb, bitmap live)
3691 /* These regs are considered always live so if they end up dying
3692 because of some def, we need to bring the back again. */
3693 if (bb_has_eh_pred (bb))
3694 bitmap_ior_into (live, &df->eh_block_artificial_uses);
3696 bitmap_ior_into (live, &df->regular_block_artificial_uses);
3700 /*----------------------------------------------------------------------------
3701 The following three functions are used only for BACKWARDS scanning:
3702 i.e. they process the defs before the uses.
3704 df_simulate_initialize_backwards should be called first with a
3705 bitvector copyied from the DF_LIVE_OUT or DF_LR_OUT. Then
3706 df_simulate_one_insn_backwards should be called for each insn in
3707 the block, starting with the last one. Finally,
3708 df_simulate_finalize_backwards can be called to get a new value
3709 of the sets at the top of the block (this is rarely used).
3710 ----------------------------------------------------------------------------*/
3712 /* Apply the artificial uses and defs at the end of BB in a backwards
3716 df_simulate_initialize_backwards (basic_block bb, bitmap live)
3720 int bb_index = bb->index;
3722 for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
3724 df_ref def = *def_rec;
3725 if ((DF_REF_FLAGS (def) & DF_REF_AT_TOP) == 0)
3726 bitmap_clear_bit (live, DF_REF_REGNO (def));
3729 for (use_rec = df_get_artificial_uses (bb_index); *use_rec; use_rec++)
3731 df_ref use = *use_rec;
3732 if ((DF_REF_FLAGS (use) & DF_REF_AT_TOP) == 0)
3733 bitmap_set_bit (live, DF_REF_REGNO (use));
3738 /* Simulate the backwards effects of INSN on the bitmap LIVE. */
3741 df_simulate_one_insn_backwards (basic_block bb, rtx insn, bitmap live)
3743 if (!NONDEBUG_INSN_P (insn))
3746 df_simulate_defs (insn, live);
3747 df_simulate_uses (insn, live);
3748 df_simulate_fixup_sets (bb, live);
3752 /* Apply the artificial uses and defs at the top of BB in a backwards
3756 df_simulate_finalize_backwards (basic_block bb, bitmap live)
3762 int bb_index = bb->index;
3764 for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
3766 df_ref def = *def_rec;
3767 if (DF_REF_FLAGS (def) & DF_REF_AT_TOP)
3768 bitmap_clear_bit (live, DF_REF_REGNO (def));
3772 for (use_rec = df_get_artificial_uses (bb_index); *use_rec; use_rec++)
3774 df_ref use = *use_rec;
3775 if (DF_REF_FLAGS (use) & DF_REF_AT_TOP)
3776 bitmap_set_bit (live, DF_REF_REGNO (use));
3780 /*----------------------------------------------------------------------------
3781 The following three functions are used only for FORWARDS scanning:
3782 i.e. they process the defs and the REG_DEAD and REG_UNUSED notes.
3783 Thus it is important to add the DF_NOTES problem to the stack of
3784 problems computed before using these functions.
3786 df_simulate_initialize_forwards should be called first with a
3787 bitvector copyied from the DF_LIVE_IN or DF_LR_IN. Then
3788 df_simulate_one_insn_forwards should be called for each insn in
3789 the block, starting with the first one.
3790 ----------------------------------------------------------------------------*/
3792 /* Initialize the LIVE bitmap, which should be copied from DF_LIVE_IN or
3793 DF_LR_IN for basic block BB, for forward scanning by marking artificial
3797 df_simulate_initialize_forwards (basic_block bb, bitmap live)
3800 int bb_index = bb->index;
3802 for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
3804 df_ref def = *def_rec;
3805 if (DF_REF_FLAGS (def) & DF_REF_AT_TOP)
3806 bitmap_set_bit (live, DF_REF_REGNO (def));
3810 /* Simulate the forwards effects of INSN on the bitmap LIVE. */
3813 df_simulate_one_insn_forwards (basic_block bb, rtx insn, bitmap live)
3816 if (! INSN_P (insn))
3819 /* Make sure that DF_NOTE really is an active df problem. */
3820 gcc_assert (df_note);
3822 /* Note that this is the opposite as how the problem is defined, because
3823 in the LR problem defs _kill_ liveness. However, they do so backwards,
3824 while here the scan is performed forwards! So, first assume that the
3825 def is live, and if this is not true REG_UNUSED notes will rectify the
3827 df_simulate_find_noclobber_defs (insn, live);
3829 /* Clear all of the registers that go dead. */
3830 for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
3832 switch (REG_NOTE_KIND (link))
3837 rtx reg = XEXP (link, 0);
3838 int regno = REGNO (reg);
3839 if (HARD_REGISTER_NUM_P (regno))
3840 bitmap_clear_range (live, regno,
3841 hard_regno_nregs[regno][GET_MODE (reg)]);
3843 bitmap_clear_bit (live, regno);
3850 df_simulate_fixup_sets (bb, live);
3853 /* Used by the next two functions to encode information about the
3854 memory references we found. */
3855 #define MEMREF_NORMAL 1
3856 #define MEMREF_VOLATILE 2
3858 /* A subroutine of can_move_insns_across_p called through for_each_rtx.
3859 Return either MEMREF_NORMAL or MEMREF_VOLATILE if a memory is found. */
3862 find_memory (rtx *px, void *data ATTRIBUTE_UNUSED)
3866 if (GET_CODE (x) == ASM_OPERANDS && MEM_VOLATILE_P (x))
3867 return MEMREF_VOLATILE;
3871 if (MEM_VOLATILE_P (x))
3872 return MEMREF_VOLATILE;
3873 if (MEM_READONLY_P (x))
3876 return MEMREF_NORMAL;
3879 /* A subroutine of can_move_insns_across_p called through note_stores.
3880 DATA points to an integer in which we set either the bit for
3881 MEMREF_NORMAL or the bit for MEMREF_VOLATILE if we find a MEM
3885 find_memory_stores (rtx x, const_rtx pat ATTRIBUTE_UNUSED,
3886 void *data ATTRIBUTE_UNUSED)
3888 int *pflags = (int *)data;
3889 if (GET_CODE (x) == SUBREG)
3891 /* Treat stores to SP as stores to memory, this will prevent problems
3892 when there are references to the stack frame. */
3893 if (x == stack_pointer_rtx)
3894 *pflags |= MEMREF_VOLATILE;
3897 *pflags |= MEM_VOLATILE_P (x) ? MEMREF_VOLATILE : MEMREF_NORMAL;
3900 /* Scan BB backwards, using df_simulate functions to keep track of
3901 lifetimes, up to insn POINT. The result is stored in LIVE. */
3904 simulate_backwards_to_point (basic_block bb, regset live, rtx point)
3907 bitmap_copy (live, df_get_live_out (bb));
3908 df_simulate_initialize_backwards (bb, live);
3910 /* Scan and update life information until we reach the point we're
3912 for (insn = BB_END (bb); insn != point; insn = PREV_INSN (insn))
3913 df_simulate_one_insn_backwards (bb, insn, live);
3916 /* Return true if it is safe to move a group of insns, described by
3917 the range FROM to TO, backwards across another group of insns,
3918 described by ACROSS_FROM to ACROSS_TO. It is assumed that there
3919 are no insns between ACROSS_TO and FROM, but they may be in
3920 different basic blocks; MERGE_BB is the block from which the
3921 insns will be moved. The caller must pass in a regset MERGE_LIVE
3922 which specifies the registers live after TO.
3924 This function may be called in one of two cases: either we try to
3925 move identical instructions from all successor blocks into their
3926 predecessor, or we try to move from only one successor block. If
3927 OTHER_BRANCH_LIVE is nonnull, it indicates that we're dealing with
3928 the second case. It should contain a set of registers live at the
3929 end of ACROSS_TO which must not be clobbered by moving the insns.
3930 In that case, we're also more careful about moving memory references
3933 We return false if it is not safe to move the entire group, but it
3934 may still be possible to move a subgroup. PMOVE_UPTO, if nonnull,
3935 is set to point at the last moveable insn in such a case. */
3938 can_move_insns_across (rtx from, rtx to, rtx across_from, rtx across_to,
3939 basic_block merge_bb, regset merge_live,
3940 regset other_branch_live, rtx *pmove_upto)
3942 rtx insn, next, max_to;
3943 bitmap merge_set, merge_use, local_merge_live;
3944 bitmap test_set, test_use;
3945 unsigned i, fail = 0;
3947 int memrefs_in_across = 0;
3948 int mem_sets_in_across = 0;
3949 bool trapping_insns_in_across = false;
3951 if (pmove_upto != NULL)
3952 *pmove_upto = NULL_RTX;
3954 /* Find real bounds, ignoring debug insns. */
3955 while (!NONDEBUG_INSN_P (from) && from != to)
3956 from = NEXT_INSN (from);
3957 while (!NONDEBUG_INSN_P (to) && from != to)
3958 to = PREV_INSN (to);
3960 for (insn = across_to; ; insn = next)
3962 if (NONDEBUG_INSN_P (insn))
3964 memrefs_in_across |= for_each_rtx (&PATTERN (insn), find_memory,
3966 note_stores (PATTERN (insn), find_memory_stores,
3967 &mem_sets_in_across);
3968 /* This is used just to find sets of the stack pointer. */
3969 memrefs_in_across |= mem_sets_in_across;
3970 trapping_insns_in_across |= may_trap_p (PATTERN (insn));
3972 next = PREV_INSN (insn);
3973 if (insn == across_from)
3978 MERGE_SET = set of registers set in MERGE_BB
3979 MERGE_USE = set of registers used in MERGE_BB and live at its top
3980 MERGE_LIVE = set of registers live at the point inside the MERGE
3981 range that we've reached during scanning
3982 TEST_SET = set of registers set between ACROSS_FROM and ACROSS_END.
3983 TEST_USE = set of registers used between ACROSS_FROM and ACROSS_END,
3984 and live before ACROSS_FROM. */
3986 merge_set = BITMAP_ALLOC (®_obstack);
3987 merge_use = BITMAP_ALLOC (®_obstack);
3988 local_merge_live = BITMAP_ALLOC (®_obstack);
3989 test_set = BITMAP_ALLOC (®_obstack);
3990 test_use = BITMAP_ALLOC (®_obstack);
3992 /* Compute the set of registers set and used in the ACROSS range. */
3993 if (other_branch_live != NULL)
3994 bitmap_copy (test_use, other_branch_live);
3995 df_simulate_initialize_backwards (merge_bb, test_use);
3996 for (insn = across_to; ; insn = next)
3998 if (NONDEBUG_INSN_P (insn))
4000 df_simulate_find_defs (insn, test_set);
4001 df_simulate_defs (insn, test_use);
4002 df_simulate_uses (insn, test_use);
4004 next = PREV_INSN (insn);
4005 if (insn == across_from)
4009 /* Compute an upper bound for the amount of insns moved, by finding
4010 the first insn in MERGE that sets a register in TEST_USE, or uses
4011 a register in TEST_SET. We also check for calls, trapping operations,
4012 and memory references. */
4014 for (insn = from; ; insn = next)
4018 if (NOTE_P (insn) && NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
4020 if (NONDEBUG_INSN_P (insn))
4022 if (may_trap_or_fault_p (PATTERN (insn))
4023 && (trapping_insns_in_across || other_branch_live != NULL))
4026 /* We cannot move memory stores past each other, or move memory
4027 reads past stores, at least not without tracking them and
4028 calling true_dependence on every pair.
4030 If there is no other branch and no memory references or
4031 sets in the ACROSS range, we can move memory references
4032 freely, even volatile ones.
4034 Otherwise, the rules are as follows: volatile memory
4035 references and stores can't be moved at all, and any type
4036 of memory reference can't be moved if there are volatile
4037 accesses or stores in the ACROSS range. That leaves
4038 normal reads, which can be moved, as the trapping case is
4039 dealt with elsewhere. */
4040 if (other_branch_live != NULL || memrefs_in_across != 0)
4042 int mem_ref_flags = 0;
4043 int mem_set_flags = 0;
4044 note_stores (PATTERN (insn), find_memory_stores, &mem_set_flags);
4045 mem_ref_flags = for_each_rtx (&PATTERN (insn), find_memory,
4047 /* Catch sets of the stack pointer. */
4048 mem_ref_flags |= mem_set_flags;
4050 if ((mem_ref_flags | mem_set_flags) & MEMREF_VOLATILE)
4052 if ((memrefs_in_across & MEMREF_VOLATILE) && mem_ref_flags != 0)
4054 if (mem_set_flags != 0
4055 || (mem_sets_in_across != 0 && mem_ref_flags != 0))
4058 df_simulate_find_uses (insn, merge_use);
4059 /* We're only interested in uses which use a value live at
4060 the top, not one previously set in this block. */
4061 bitmap_and_compl_into (merge_use, merge_set);
4062 df_simulate_find_defs (insn, merge_set);
4063 if (bitmap_intersect_p (merge_set, test_use)
4064 || bitmap_intersect_p (merge_use, test_set))
4067 if (!sets_cc0_p (insn))
4071 next = NEXT_INSN (insn);
4078 if (max_to == NULL_RTX || (fail && pmove_upto == NULL))
4081 /* Now, lower this upper bound by also taking into account that
4082 a range of insns moved across ACROSS must not leave a register
4083 live at the end that will be clobbered in ACROSS. We need to
4084 find a point where TEST_SET & LIVE == 0.
4086 Insns in the MERGE range that set registers which are also set
4087 in the ACROSS range may still be moved as long as we also move
4088 later insns which use the results of the set, and make the
4089 register dead again. This is verified by the condition stated
4090 above. We only need to test it for registers that are set in
4093 MERGE_LIVE is provided by the caller and holds live registers after
4095 bitmap_copy (local_merge_live, merge_live);
4096 for (insn = to; insn != max_to; insn = PREV_INSN (insn))
4097 df_simulate_one_insn_backwards (merge_bb, insn, local_merge_live);
4099 /* We're not interested in registers that aren't set in the moved
4101 bitmap_and_into (local_merge_live, merge_set);
4104 if (NONDEBUG_INSN_P (insn))
4106 if (!bitmap_intersect_p (test_set, local_merge_live)
4108 && !sets_cc0_p (insn)
4116 df_simulate_one_insn_backwards (merge_bb, insn,
4124 insn = PREV_INSN (insn);
4131 *pmove_upto = max_to;
4133 /* For small register class machines, don't lengthen lifetimes of
4134 hard registers before reload. */
4135 if (! reload_completed
4136 && targetm.small_register_classes_for_mode_p (VOIDmode))
4138 EXECUTE_IF_SET_IN_BITMAP (merge_set, 0, i, bi)
4140 if (i < FIRST_PSEUDO_REGISTER
4142 && ! global_regs[i])
4148 BITMAP_FREE (merge_set);
4149 BITMAP_FREE (merge_use);
4150 BITMAP_FREE (local_merge_live);
4151 BITMAP_FREE (test_set);
4152 BITMAP_FREE (test_use);
4158 /*----------------------------------------------------------------------------
4159 MULTIPLE DEFINITIONS
4161 Find the locations in the function reached by multiple definition sites
4162 for a live pseudo. In and out bitvectors are built for each basic
4163 block. They are restricted for efficiency to live registers.
4165 The gen and kill sets for the problem are obvious. Together they
4166 include all defined registers in a basic block; the gen set includes
4167 registers where a partial or conditional or may-clobber definition is
4168 last in the BB, while the kill set includes registers with a complete
4169 definition coming last. However, the computation of the dataflow
4170 itself is interesting.
4172 The idea behind it comes from SSA form's iterated dominance frontier
4173 criterion for inserting PHI functions. Just like in that case, we can use
4174 the dominance frontier to find places where multiple definitions meet;
4175 a register X defined in a basic block BB1 has multiple definitions in
4176 basic blocks in BB1's dominance frontier.
4178 So, the in-set of a basic block BB2 is not just the union of the
4179 out-sets of BB2's predecessors, but includes some more bits that come
4180 from the basic blocks of whose dominance frontier BB2 is part (BB1 in
4181 the previous paragraph). I called this set the init-set of BB2.
4183 (Note: I actually use the kill-set only to build the init-set.
4184 gen bits are anyway propagated from BB1 to BB2 by dataflow).
4186 For example, if you have
4190 if <...> goto BB2 else goto BB3;
4198 you have BB3 in BB2's dominance frontier but not in BB1's, so that the
4199 init-set of BB3 includes r10 and r12, but not r11. Note that we do
4200 not need to iterate the dominance frontier, because we do not insert
4201 anything like PHI functions there! Instead, dataflow will take care of
4202 propagating the information to BB3's successors.
4203 ---------------------------------------------------------------------------*/
4205 /* Private data used to verify the solution for this problem. */
4206 struct df_md_problem_data
4208 /* An obstack for the bitmaps we need for this problem. */
4209 bitmap_obstack md_bitmaps;
4212 /* Scratch var used by transfer functions. This is used to do md analysis
4213 only for live registers. */
4214 static bitmap_head df_md_scratch;
4218 df_md_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
4221 struct df_md_bb_info *bb_info = (struct df_md_bb_info *) vbb_info;
4224 bitmap_clear (&bb_info->kill);
4225 bitmap_clear (&bb_info->gen);
4226 bitmap_clear (&bb_info->init);
4227 bitmap_clear (&bb_info->in);
4228 bitmap_clear (&bb_info->out);
4233 /* Allocate or reset bitmaps for DF_MD. The solution bits are
4234 not touched unless the block is new. */
4237 df_md_alloc (bitmap all_blocks)
4239 unsigned int bb_index;
4241 struct df_md_problem_data *problem_data;
4243 df_grow_bb_info (df_md);
4244 if (df_md->problem_data)
4245 problem_data = (struct df_md_problem_data *) df_md->problem_data;
4248 problem_data = XNEW (struct df_md_problem_data);
4249 df_md->problem_data = problem_data;
4250 bitmap_obstack_initialize (&problem_data->md_bitmaps);
4252 bitmap_initialize (&df_md_scratch, &problem_data->md_bitmaps);
4254 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
4256 struct df_md_bb_info *bb_info = df_md_get_bb_info (bb_index);
4257 /* When bitmaps are already initialized, just clear them. */
4258 if (bb_info->init.obstack)
4260 bitmap_clear (&bb_info->init);
4261 bitmap_clear (&bb_info->gen);
4262 bitmap_clear (&bb_info->kill);
4263 bitmap_clear (&bb_info->in);
4264 bitmap_clear (&bb_info->out);
4268 bitmap_initialize (&bb_info->init, &problem_data->md_bitmaps);
4269 bitmap_initialize (&bb_info->gen, &problem_data->md_bitmaps);
4270 bitmap_initialize (&bb_info->kill, &problem_data->md_bitmaps);
4271 bitmap_initialize (&bb_info->in, &problem_data->md_bitmaps);
4272 bitmap_initialize (&bb_info->out, &problem_data->md_bitmaps);
4276 df_md->optional_p = true;
4279 /* Add the effect of the top artificial defs of BB to the multiple definitions
4283 df_md_simulate_artificial_defs_at_top (basic_block bb, bitmap local_md)
4285 int bb_index = bb->index;
4287 for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
4289 df_ref def = *def_rec;
4290 if (DF_REF_FLAGS (def) & DF_REF_AT_TOP)
4292 unsigned int dregno = DF_REF_REGNO (def);
4293 if (DF_REF_FLAGS (def)
4294 & (DF_REF_PARTIAL | DF_REF_CONDITIONAL | DF_REF_MAY_CLOBBER))
4295 bitmap_set_bit (local_md, dregno);
4297 bitmap_clear_bit (local_md, dregno);
4303 /* Add the effect of the defs of INSN to the reaching definitions bitmap
4307 df_md_simulate_one_insn (basic_block bb ATTRIBUTE_UNUSED, rtx insn,
4310 unsigned uid = INSN_UID (insn);
4313 for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
4315 df_ref def = *def_rec;
4316 unsigned int dregno = DF_REF_REGNO (def);
4317 if ((!(df->changeable_flags & DF_NO_HARD_REGS))
4318 || (dregno >= FIRST_PSEUDO_REGISTER))
4320 if (DF_REF_FLAGS (def)
4321 & (DF_REF_PARTIAL | DF_REF_CONDITIONAL | DF_REF_MAY_CLOBBER))
4322 bitmap_set_bit (local_md, DF_REF_ID (def));
4324 bitmap_clear_bit (local_md, DF_REF_ID (def));
4330 df_md_bb_local_compute_process_def (struct df_md_bb_info *bb_info,
4335 bitmap_clear (&seen_in_insn);
4337 while ((def = *def_rec++) != NULL)
4339 unsigned int dregno = DF_REF_REGNO (def);
4340 if (((!(df->changeable_flags & DF_NO_HARD_REGS))
4341 || (dregno >= FIRST_PSEUDO_REGISTER))
4342 && top_flag == (DF_REF_FLAGS (def) & DF_REF_AT_TOP))
4344 if (!bitmap_bit_p (&seen_in_insn, dregno))
4346 if (DF_REF_FLAGS (def)
4347 & (DF_REF_PARTIAL | DF_REF_CONDITIONAL | DF_REF_MAY_CLOBBER))
4349 bitmap_set_bit (&bb_info->gen, dregno);
4350 bitmap_clear_bit (&bb_info->kill, dregno);
4354 /* When we find a clobber and a regular def,
4355 make sure the regular def wins. */
4356 bitmap_set_bit (&seen_in_insn, dregno);
4357 bitmap_set_bit (&bb_info->kill, dregno);
4358 bitmap_clear_bit (&bb_info->gen, dregno);
4366 /* Compute local multiple def info for basic block BB. */
4369 df_md_bb_local_compute (unsigned int bb_index)
4371 basic_block bb = BASIC_BLOCK (bb_index);
4372 struct df_md_bb_info *bb_info = df_md_get_bb_info (bb_index);
4375 /* Artificials are only hard regs. */
4376 if (!(df->changeable_flags & DF_NO_HARD_REGS))
4377 df_md_bb_local_compute_process_def (bb_info,
4378 df_get_artificial_defs (bb_index),
4381 FOR_BB_INSNS (bb, insn)
4383 unsigned int uid = INSN_UID (insn);
4387 df_md_bb_local_compute_process_def (bb_info, DF_INSN_UID_DEFS (uid), 0);
4390 if (!(df->changeable_flags & DF_NO_HARD_REGS))
4391 df_md_bb_local_compute_process_def (bb_info,
4392 df_get_artificial_defs (bb_index),
4396 /* Compute local reaching def info for each basic block within BLOCKS. */
4399 df_md_local_compute (bitmap all_blocks)
4401 unsigned int bb_index, df_bb_index;
4402 bitmap_iterator bi1, bi2;
4404 bitmap_head *frontiers;
4406 bitmap_initialize (&seen_in_insn, &bitmap_default_obstack);
4408 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi1)
4410 df_md_bb_local_compute (bb_index);
4413 bitmap_clear (&seen_in_insn);
4415 frontiers = XNEWVEC (bitmap_head, last_basic_block);
4417 bitmap_initialize (&frontiers[bb->index], &bitmap_default_obstack);
4419 compute_dominance_frontiers (frontiers);
4421 /* Add each basic block's kills to the nodes in the frontier of the BB. */
4422 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi1)
4424 bitmap kill = &df_md_get_bb_info (bb_index)->kill;
4425 EXECUTE_IF_SET_IN_BITMAP (&frontiers[bb_index], 0, df_bb_index, bi2)
4427 basic_block bb = BASIC_BLOCK (df_bb_index);
4428 if (bitmap_bit_p (all_blocks, df_bb_index))
4429 bitmap_ior_and_into (&df_md_get_bb_info (df_bb_index)->init, kill,
4430 df_get_live_in (bb));
4435 bitmap_clear (&frontiers[bb->index]);
4440 /* Reset the global solution for recalculation. */
4443 df_md_reset (bitmap all_blocks)
4445 unsigned int bb_index;
4448 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
4450 struct df_md_bb_info *bb_info = df_md_get_bb_info (bb_index);
4451 gcc_assert (bb_info);
4452 bitmap_clear (&bb_info->in);
4453 bitmap_clear (&bb_info->out);
4458 df_md_transfer_function (int bb_index)
4460 basic_block bb = BASIC_BLOCK (bb_index);
4461 struct df_md_bb_info *bb_info = df_md_get_bb_info (bb_index);
4462 bitmap in = &bb_info->in;
4463 bitmap out = &bb_info->out;
4464 bitmap gen = &bb_info->gen;
4465 bitmap kill = &bb_info->kill;
4467 /* We need to use a scratch set here so that the value returned from this
4468 function invocation properly reflects whether the sets changed in a
4469 significant way; i.e. not just because the live set was anded in. */
4470 bitmap_and (&df_md_scratch, gen, df_get_live_out (bb));
4472 /* Multiple definitions of a register are not relevant if it is not
4473 live. Thus we trim the result to the places where it is live. */
4474 bitmap_and_into (in, df_get_live_in (bb));
4476 return bitmap_ior_and_compl (out, &df_md_scratch, in, kill);
4479 /* Initialize the solution bit vectors for problem. */
4482 df_md_init (bitmap all_blocks)
4484 unsigned int bb_index;
4487 EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
4489 struct df_md_bb_info *bb_info = df_md_get_bb_info (bb_index);
4491 bitmap_copy (&bb_info->in, &bb_info->init);
4492 df_md_transfer_function (bb_index);
4497 df_md_confluence_0 (basic_block bb)
4499 struct df_md_bb_info *bb_info = df_md_get_bb_info (bb->index);
4500 bitmap_copy (&bb_info->in, &bb_info->init);
4503 /* In of target gets or of out of source. */
4506 df_md_confluence_n (edge e)
4508 bitmap op1 = &df_md_get_bb_info (e->dest->index)->in;
4509 bitmap op2 = &df_md_get_bb_info (e->src->index)->out;
4511 if (e->flags & EDGE_FAKE)
4514 if (e->flags & EDGE_EH)
4515 return bitmap_ior_and_compl_into (op1, op2,
4516 regs_invalidated_by_call_regset);
4518 return bitmap_ior_into (op1, op2);
4521 /* Free all storage associated with the problem. */
4526 struct df_md_problem_data *problem_data
4527 = (struct df_md_problem_data *) df_md->problem_data;
4529 bitmap_obstack_release (&problem_data->md_bitmaps);
4530 free (problem_data);
4531 df_md->problem_data = NULL;
4533 df_md->block_info_size = 0;
4534 free (df_md->block_info);
4535 df_md->block_info = NULL;
4540 /* Debugging info at top of bb. */
4543 df_md_top_dump (basic_block bb, FILE *file)
4545 struct df_md_bb_info *bb_info = df_md_get_bb_info (bb->index);
4549 fprintf (file, ";; md in \t");
4550 df_print_regset (file, &bb_info->in);
4551 fprintf (file, ";; md init \t");
4552 df_print_regset (file, &bb_info->init);
4553 fprintf (file, ";; md gen \t");
4554 df_print_regset (file, &bb_info->gen);
4555 fprintf (file, ";; md kill \t");
4556 df_print_regset (file, &bb_info->kill);
4559 /* Debugging info at bottom of bb. */
4562 df_md_bottom_dump (basic_block bb, FILE *file)
4564 struct df_md_bb_info *bb_info = df_md_get_bb_info (bb->index);
4568 fprintf (file, ";; md out \t");
4569 df_print_regset (file, &bb_info->out);
4572 static struct df_problem problem_MD =
4574 DF_MD, /* Problem id. */
4575 DF_FORWARD, /* Direction. */
4576 df_md_alloc, /* Allocate the problem specific data. */
4577 df_md_reset, /* Reset global information. */
4578 df_md_free_bb_info, /* Free basic block info. */
4579 df_md_local_compute, /* Local compute function. */
4580 df_md_init, /* Init the solution specific data. */
4581 df_worklist_dataflow, /* Worklist solver. */
4582 df_md_confluence_0, /* Confluence operator 0. */
4583 df_md_confluence_n, /* Confluence operator n. */
4584 df_md_transfer_function, /* Transfer function. */
4585 NULL, /* Finalize function. */
4586 df_md_free, /* Free all of the problem information. */
4587 df_md_free, /* Remove this problem from the stack of dataflow problems. */
4588 NULL, /* Debugging. */
4589 df_md_top_dump, /* Debugging start block. */
4590 df_md_bottom_dump, /* Debugging end block. */
4591 NULL, /* Incremental solution verify start. */
4592 NULL, /* Incremental solution verify end. */
4593 NULL, /* Dependent problem. */
4594 sizeof (struct df_md_bb_info),/* Size of entry of block_info array. */
4595 TV_DF_MD, /* Timing variable. */
4596 false /* Reset blocks on dropping out of blocks_to_analyze. */
4599 /* Create a new MD instance and add it to the existing instance
4603 df_md_add_problem (void)
4605 df_add_problem (&problem_MD);