Line data Source code
1 : /* Control flow graph manipulation code for GNU compiler.
2 : Copyright (C) 1987-2026 Free Software Foundation, Inc.
3 :
4 : This file is part of GCC.
5 :
6 : GCC is free software; you can redistribute it and/or modify it under
7 : the terms of the GNU General Public License as published by the Free
8 : Software Foundation; either version 3, or (at your option) any later
9 : version.
10 :
11 : GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 : WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 : FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 : for more details.
15 :
16 : You should have received a copy of the GNU General Public License
17 : along with GCC; see the file COPYING3. If not see
18 : <http://www.gnu.org/licenses/>. */
19 :
20 : /* This file contains low level functions to manipulate the CFG and analyze it
21 : that are aware of the RTL intermediate language.
22 :
23 : Available functionality:
24 : - Basic CFG/RTL manipulation API documented in cfghooks.h
25 : - CFG-aware instruction chain manipulation
26 : delete_insn, delete_insn_chain
27 : - Edge splitting and committing to edges
28 : insert_insn_on_edge, prepend_insn_to_edge, commit_edge_insertions
29 : - CFG updating after insn simplification
30 : purge_dead_edges, purge_all_dead_edges
31 : - CFG fixing after coarse manipulation
32 : fixup_abnormal_edges
33 :
34 : Functions not supposed for generic use:
35 : - Infrastructure to determine quickly basic block for insn
36 : compute_bb_for_insn, update_bb_for_insn, set_block_for_insn,
37 : - Edge redirection with updating and optimizing of insn chain
38 : block_label, tidy_fallthru_edge, force_nonfallthru */
39 :
40 : #include "config.h"
41 : #include "system.h"
42 : #include "coretypes.h"
43 : #include "backend.h"
44 : #include "target.h"
45 : #include "rtl.h"
46 : #include "tree.h"
47 : #include "cfghooks.h"
48 : #include "df.h"
49 : #include "insn-config.h"
50 : #include "memmodel.h"
51 : #include "emit-rtl.h"
52 : #include "cfgrtl.h"
53 : #include "cfganal.h"
54 : #include "cfgbuild.h"
55 : #include "cfgcleanup.h"
56 : #include "bb-reorder.h"
57 : #include "rtl-error.h"
58 : #include "insn-attr.h"
59 : #include "dojump.h"
60 : #include "expr.h"
61 : #include "cfgloop.h"
62 : #include "tree-pass.h"
63 : #include "print-rtl.h"
64 : #include "rtl-iter.h"
65 : #include "gimplify.h"
66 : #include "profile.h"
67 : #include "sreal.h"
68 :
69 : /* Disable warnings about missing quoting in GCC diagnostics. */
70 : #if __GNUC__ >= 10
71 : # pragma GCC diagnostic push
72 : # pragma GCC diagnostic ignored "-Wformat-diag"
73 : #endif
74 :
75 : /* Holds the interesting leading and trailing notes for the function.
76 : Only applicable if the CFG is in cfglayout mode. */
77 : static GTY(()) rtx_insn *cfg_layout_function_footer;
78 : static GTY(()) rtx_insn *cfg_layout_function_header;
79 :
80 : static rtx_insn *skip_insns_after_block (basic_block);
81 : static void record_effective_endpoints (void);
82 : static void fixup_reorder_chain (void);
83 :
84 : void verify_insn_chain (void);
85 : static void fixup_fallthru_exit_predecessor (void);
86 : static bool can_delete_note_p (const rtx_note *);
87 : static bool can_delete_label_p (const rtx_code_label *);
88 : static basic_block rtl_split_edge (edge);
89 : static bool rtl_move_block_after (basic_block, basic_block);
90 : static bool rtl_verify_flow_info (void);
91 : static basic_block cfg_layout_split_block (basic_block, void *);
92 : static edge cfg_layout_redirect_edge_and_branch (edge, basic_block);
93 : static basic_block cfg_layout_redirect_edge_and_branch_force (edge, basic_block);
94 : static void cfg_layout_delete_block (basic_block);
95 : static void rtl_delete_block (basic_block);
96 : static basic_block rtl_redirect_edge_and_branch_force (edge, basic_block);
97 : static edge rtl_redirect_edge_and_branch (edge, basic_block);
98 : static basic_block rtl_split_block (basic_block, void *);
99 : static void rtl_dump_bb (FILE *, basic_block, int, dump_flags_t);
100 : static bool rtl_verify_flow_info_1 (void);
101 : static void rtl_make_forwarder_block (edge);
102 : static bool rtl_bb_info_initialized_p (basic_block bb);
103 :
104 : /* Return true if NOTE is not one of the ones that must be kept paired,
105 : so that we may simply delete it. */
106 :
107 : static bool
108 10570242 : can_delete_note_p (const rtx_note *note)
109 : {
110 0 : switch (NOTE_KIND (note))
111 : {
112 : case NOTE_INSN_DELETED:
113 : case NOTE_INSN_BASIC_BLOCK:
114 : case NOTE_INSN_EPILOGUE_BEG:
115 : return true;
116 :
117 0 : default:
118 0 : return false;
119 : }
120 : }
121 :
122 : /* True if a given label can be deleted. */
123 :
124 : static bool
125 7665080 : can_delete_label_p (const rtx_code_label *label)
126 : {
127 7665080 : return (!LABEL_PRESERVE_P (label)
128 : /* User declared labels must be preserved. */
129 7657716 : && LABEL_NAME (label) == 0
130 7665080 : && !vec_safe_contains<rtx_insn *> (forced_labels,
131 7612824 : const_cast<rtx_code_label *> (label)));
132 : }
133 :
134 : /* Delete INSN by patching it out. */
135 :
136 : void
137 127774213 : delete_insn (rtx_insn *insn)
138 : {
139 127774213 : rtx note;
140 127774213 : bool really_delete = true;
141 :
142 127774213 : if (LABEL_P (insn))
143 : {
144 : /* Some labels can't be directly removed from the INSN chain, as they
145 : might be references via variables, constant pool etc.
146 : Convert them to the special NOTE_INSN_DELETED_LABEL note. */
147 7665080 : if (! can_delete_label_p (as_a <rtx_code_label *> (insn)))
148 : {
149 52256 : const char *name = LABEL_NAME (insn);
150 52256 : basic_block bb = BLOCK_FOR_INSN (insn);
151 52256 : rtx_insn *bb_note = NEXT_INSN (insn);
152 :
153 52256 : really_delete = false;
154 52256 : PUT_CODE (insn, NOTE);
155 52256 : NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL;
156 52256 : NOTE_DELETED_LABEL_NAME (insn) = name;
157 :
158 : /* If the note following the label starts a basic block, and the
159 : label is a member of the same basic block, interchange the two. */
160 52256 : if (bb_note != NULL_RTX
161 52165 : && NOTE_INSN_BASIC_BLOCK_P (bb_note)
162 13328 : && bb != NULL
163 65584 : && bb == BLOCK_FOR_INSN (bb_note))
164 : {
165 11401 : reorder_insns_nobb (insn, insn, bb_note);
166 11401 : BB_HEAD (bb) = bb_note;
167 11401 : if (BB_END (bb) == bb_note)
168 1507 : BB_END (bb) = insn;
169 : }
170 : }
171 :
172 7665080 : remove_node_from_insn_list (insn, &nonlocal_goto_handler_labels);
173 : }
174 :
175 7665080 : if (really_delete)
176 : {
177 : /* If this insn has already been deleted, something is very wrong. */
178 127721957 : gcc_assert (!insn->deleted ());
179 127721957 : if (INSN_P (insn))
180 93776193 : df_insn_delete (insn);
181 127721957 : remove_insn (insn);
182 127721957 : insn->set_deleted ();
183 : }
184 :
185 : /* If deleting a jump, decrement the use count of the label. Deleting
186 : the label itself should happen in the normal course of block merging. */
187 127774213 : if (JUMP_P (insn))
188 : {
189 6778886 : if (JUMP_LABEL (insn)
190 6778678 : && LABEL_P (JUMP_LABEL (insn)))
191 6768880 : LABEL_NUSES (JUMP_LABEL (insn))--;
192 :
193 : /* If there are more targets, remove them too. */
194 : while ((note
195 13557772 : = find_reg_note (insn, REG_LABEL_TARGET, NULL_RTX)) != NULL_RTX
196 6778886 : && LABEL_P (XEXP (note, 0)))
197 : {
198 0 : LABEL_NUSES (XEXP (note, 0))--;
199 0 : remove_note (insn, note);
200 : }
201 : }
202 :
203 : /* Also if deleting any insn that references a label as an operand. */
204 255567112 : while ((note = find_reg_note (insn, REG_LABEL_OPERAND, NULL_RTX)) != NULL_RTX
205 127783556 : && LABEL_P (XEXP (note, 0)))
206 : {
207 9343 : LABEL_NUSES (XEXP (note, 0))--;
208 9343 : remove_note (insn, note);
209 : }
210 :
211 127774213 : if (rtx_jump_table_data *table = dyn_cast <rtx_jump_table_data *> (insn))
212 : {
213 7 : rtvec vec = table->get_labels ();
214 7 : int len = GET_NUM_ELEM (vec);
215 7 : int i;
216 :
217 84 : for (i = 0; i < len; i++)
218 : {
219 77 : rtx label = XEXP (RTVEC_ELT (vec, i), 0);
220 :
221 : /* When deleting code in bulk (e.g. removing many unreachable
222 : blocks) we can delete a label that's a target of the vector
223 : before deleting the vector itself. */
224 77 : if (!NOTE_P (label))
225 77 : LABEL_NUSES (label)--;
226 : }
227 : }
228 127774213 : }
229 :
230 : /* Like delete_insn but also purge dead edges from BB.
231 : Return true if any edges are eliminated. */
232 :
233 : bool
234 12473373 : delete_insn_and_edges (rtx_insn *insn)
235 : {
236 12473373 : bool purge = false;
237 :
238 12473373 : if (NONDEBUG_INSN_P (insn) && BLOCK_FOR_INSN (insn))
239 : {
240 12096720 : basic_block bb = BLOCK_FOR_INSN (insn);
241 12096720 : if (BB_END (bb) == insn)
242 : purge = true;
243 11417689 : else if (DEBUG_INSN_P (BB_END (bb)))
244 1036795 : for (rtx_insn *dinsn = NEXT_INSN (insn);
245 1036795 : DEBUG_INSN_P (dinsn); dinsn = NEXT_INSN (dinsn))
246 700588 : if (BB_END (bb) == dinsn)
247 : {
248 : purge = true;
249 : break;
250 : }
251 : }
252 12473373 : delete_insn (insn);
253 12473373 : if (purge)
254 729180 : return purge_dead_edges (BLOCK_FOR_INSN (insn));
255 : return false;
256 : }
257 :
258 : /* Unlink a chain of insns between START and FINISH, leaving notes
259 : that must be paired. If CLEAR_BB is true, we set bb field for
260 : insns that cannot be removed to NULL. */
261 :
262 : void
263 17399294 : delete_insn_chain (rtx start, rtx_insn *finish, bool clear_bb)
264 : {
265 : /* Unchain the insns one by one. It would be quicker to delete all of these
266 : with a single unchaining, rather than one at a time, but we need to keep
267 : the NOTE's. */
268 17399294 : rtx_insn *current = finish;
269 29677273 : while (1)
270 : {
271 29677273 : rtx_insn *prev = PREV_INSN (current);
272 29677273 : if (NOTE_P (current) && !can_delete_note_p (as_a <rtx_note *> (current)))
273 : ;
274 : else
275 29671272 : delete_insn (current);
276 :
277 29677273 : if (clear_bb && !current->deleted ())
278 45317 : set_block_for_insn (current, NULL);
279 :
280 29677273 : if (current == start)
281 : break;
282 : current = prev;
283 : }
284 17399294 : }
285 :
286 : /* Create a new basic block consisting of the instructions between HEAD and END
287 : inclusive. This function is designed to allow fast BB construction - reuses
288 : the note and basic block struct in BB_NOTE, if any and do not grow
289 : BASIC_BLOCK chain and should be used directly only by CFG construction code.
290 : END can be NULL in to create new empty basic block before HEAD. Both END
291 : and HEAD can be NULL to create basic block at the end of INSN chain.
292 : AFTER is the basic block we should be put after. */
293 :
294 : basic_block
295 13056903 : create_basic_block_structure (rtx_insn *head, rtx_insn *end, rtx_note *bb_note,
296 : basic_block after)
297 : {
298 13056903 : basic_block bb;
299 :
300 13056903 : if (bb_note
301 0 : && (bb = NOTE_BASIC_BLOCK (bb_note)) != NULL
302 13056903 : && bb->aux == NULL)
303 : {
304 : /* If we found an existing note, thread it back onto the chain. */
305 :
306 0 : rtx_insn *after;
307 :
308 0 : if (LABEL_P (head))
309 : after = head;
310 : else
311 : {
312 0 : after = PREV_INSN (head);
313 0 : head = bb_note;
314 : }
315 :
316 0 : if (after != bb_note && NEXT_INSN (after) != bb_note)
317 0 : reorder_insns_nobb (bb_note, bb_note, after);
318 : }
319 : else
320 : {
321 : /* Otherwise we must create a note and a basic block structure. */
322 :
323 13056903 : bb = alloc_block ();
324 :
325 13056903 : init_rtl_bb_info (bb);
326 13056903 : if (!head && !end)
327 455862 : head = end = bb_note
328 455862 : = emit_note_after (NOTE_INSN_BASIC_BLOCK, get_last_insn ());
329 12601041 : else if (LABEL_P (head) && end)
330 : {
331 2712764 : bb_note = emit_note_after (NOTE_INSN_BASIC_BLOCK, head);
332 2712764 : if (head == end)
333 910315 : end = bb_note;
334 : }
335 : else
336 : {
337 9888277 : bb_note = emit_note_before (NOTE_INSN_BASIC_BLOCK, head);
338 9888277 : head = bb_note;
339 9888277 : if (!end)
340 5517762 : end = head;
341 : }
342 :
343 13056903 : NOTE_BASIC_BLOCK (bb_note) = bb;
344 : }
345 :
346 : /* Always include the bb note in the block. */
347 13056903 : if (NEXT_INSN (end) == bb_note)
348 0 : end = bb_note;
349 :
350 13056903 : BB_HEAD (bb) = head;
351 13056903 : BB_END (bb) = end;
352 13056903 : bb->index = last_basic_block_for_fn (cfun)++;
353 13056903 : bb->flags = BB_NEW | BB_RTL;
354 13056903 : link_block (bb, after);
355 13056903 : SET_BASIC_BLOCK_FOR_FN (cfun, bb->index, bb);
356 13056903 : df_bb_refs_record (bb->index, false);
357 13056903 : update_bb_for_insn (bb);
358 13056903 : BB_SET_PARTITION (bb, BB_UNPARTITIONED);
359 :
360 : /* Tag the block so that we know it has been used when considering
361 : other basic block notes. */
362 13056903 : bb->aux = bb;
363 :
364 13056903 : return bb;
365 : }
366 :
367 : /* Create new basic block consisting of instructions in between HEAD and END
368 : and place it to the BB chain after block AFTER. END can be NULL to
369 : create a new empty basic block before HEAD. Both END and HEAD can be
370 : NULL to create basic block at the end of INSN chain. */
371 :
372 : static basic_block
373 13056903 : rtl_create_basic_block (void *headp, void *endp, basic_block after)
374 : {
375 13056903 : rtx_insn *head = (rtx_insn *) headp;
376 13056903 : rtx_insn *end = (rtx_insn *) endp;
377 13056903 : basic_block bb;
378 :
379 : /* Grow the basic block array if needed. */
380 13056903 : if ((size_t) last_basic_block_for_fn (cfun)
381 13056903 : >= basic_block_info_for_fn (cfun)->length ())
382 823084 : vec_safe_grow_cleared (basic_block_info_for_fn (cfun),
383 823084 : last_basic_block_for_fn (cfun) + 1);
384 :
385 13056903 : n_basic_blocks_for_fn (cfun)++;
386 :
387 13056903 : bb = create_basic_block_structure (head, end, NULL, after);
388 13056903 : bb->aux = NULL;
389 13056903 : return bb;
390 : }
391 :
392 : static basic_block
393 4229796 : cfg_layout_create_basic_block (void *head, void *end, basic_block after)
394 : {
395 4229796 : basic_block newbb = rtl_create_basic_block (head, end, after);
396 :
397 4229796 : return newbb;
398 : }
399 :
400 : /* Delete the insns in a (non-live) block. We physically delete every
401 : non-deleted-note insn, and update the flow graph appropriately.
402 :
403 : Return nonzero if we deleted an exception handler. */
404 :
405 : /* ??? Preserving all such notes strikes me as wrong. It would be nice
406 : to post-process the stream to remove empty blocks, loops, ranges, etc. */
407 :
408 : static void
409 6732486 : rtl_delete_block (basic_block b)
410 : {
411 6732486 : rtx_insn *insn, *end;
412 :
413 : /* If the head of this block is a CODE_LABEL, then it might be the
414 : label for an exception handler which can't be reached. We need
415 : to remove the label from the exception_handler_label list. */
416 6732486 : insn = BB_HEAD (b);
417 :
418 6732486 : end = get_last_bb_insn (b);
419 :
420 : /* Selectively delete the entire chain. */
421 6732486 : BB_HEAD (b) = NULL;
422 6732486 : delete_insn_chain (insn, end, true);
423 :
424 :
425 6732486 : if (dump_file)
426 716 : fprintf (dump_file, "deleting block %d\n", b->index);
427 6732486 : df_bb_delete (b->index);
428 6732486 : }
429 :
430 : /* Records the basic block struct in BLOCK_FOR_INSN for every insn. */
431 :
432 : void
433 1471421 : compute_bb_for_insn (void)
434 : {
435 1471421 : basic_block bb;
436 :
437 15727850 : FOR_EACH_BB_FN (bb, cfun)
438 : {
439 14256429 : rtx_insn *end = BB_END (bb);
440 14256429 : rtx_insn *insn;
441 :
442 171367560 : for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn))
443 : {
444 171367560 : BLOCK_FOR_INSN (insn) = bb;
445 171367560 : if (insn == end)
446 : break;
447 : }
448 : }
449 1471421 : }
450 :
451 : /* Release the basic_block_for_insn array. */
452 :
453 : void
454 2943541 : free_bb_for_insn (void)
455 : {
456 2943541 : rtx_insn *insn;
457 206699984 : for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
458 203756443 : if (!BARRIER_P (insn))
459 199016024 : BLOCK_FOR_INSN (insn) = NULL;
460 2943541 : }
461 :
462 : namespace {
463 :
464 : const pass_data pass_data_free_cfg =
465 : {
466 : RTL_PASS, /* type */
467 : "*free_cfg", /* name */
468 : OPTGROUP_NONE, /* optinfo_flags */
469 : TV_NONE, /* tv_id */
470 : 0, /* properties_required */
471 : 0, /* properties_provided */
472 : PROP_cfg, /* properties_destroyed */
473 : 0, /* todo_flags_start */
474 : 0, /* todo_flags_finish */
475 : };
476 :
477 : class pass_free_cfg : public rtl_opt_pass
478 : {
479 : public:
480 285722 : pass_free_cfg (gcc::context *ctxt)
481 571444 : : rtl_opt_pass (pass_data_free_cfg, ctxt)
482 : {}
483 :
484 : /* opt_pass methods: */
485 : unsigned int execute (function *) final override;
486 :
487 : }; // class pass_free_cfg
488 :
489 : unsigned int
490 1471363 : pass_free_cfg::execute (function *)
491 : {
492 : /* The resource.cc machinery uses DF but the CFG isn't guaranteed to be
493 : valid at that point so it would be too late to call df_analyze. */
494 1471363 : if (DELAY_SLOTS && optimize > 0 && flag_delayed_branch)
495 : {
496 : df_note_add_problem ();
497 : df_analyze ();
498 : }
499 :
500 1471363 : if (crtl->has_bb_partition)
501 64348 : insert_section_boundary_note ();
502 :
503 1471363 : free_bb_for_insn ();
504 1471363 : return 0;
505 : }
506 :
507 : } // anon namespace
508 :
509 : rtl_opt_pass *
510 285722 : make_pass_free_cfg (gcc::context *ctxt)
511 : {
512 285722 : return new pass_free_cfg (ctxt);
513 : }
514 :
515 : /* Return RTX to emit after when we want to emit code on the entry of function. */
516 : rtx_insn *
517 7756 : entry_of_function (void)
518 : {
519 7756 : return (n_basic_blocks_for_fn (cfun) > NUM_FIXED_BLOCKS ?
520 7756 : BB_HEAD (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) : get_insns ());
521 : }
522 :
523 : /* Emit INSN at the entry point of the function, ensuring that it is only
524 : executed once per function. */
525 : void
526 0 : emit_insn_at_entry (rtx insn)
527 : {
528 0 : edge_iterator ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs);
529 0 : edge e = ei_safe_edge (ei);
530 0 : gcc_assert (e->flags & EDGE_FALLTHRU);
531 :
532 0 : insert_insn_on_edge (insn, e);
533 0 : commit_edge_insertions ();
534 0 : }
535 :
536 : /* Update BLOCK_FOR_INSN of insns between BEGIN and END
537 : (or BARRIER if found) and notify df of the bb change.
538 : The insn chain range is inclusive
539 : (i.e. both BEGIN and END will be updated. */
540 :
541 : void
542 33135974 : update_bb_for_insn_chain (rtx_insn *begin, rtx_insn *end, basic_block bb)
543 : {
544 33135974 : rtx_insn *insn;
545 :
546 33135974 : end = NEXT_INSN (end);
547 345977163 : for (insn = begin; insn != end; insn = NEXT_INSN (insn))
548 279705215 : if (!BARRIER_P (insn))
549 277227556 : df_insn_change_bb (insn, bb);
550 33135974 : }
551 :
552 : /* Update BLOCK_FOR_INSN of insns in BB to BB,
553 : and notify df of the change. */
554 :
555 : void
556 16609194 : update_bb_for_insn (basic_block bb)
557 : {
558 16609194 : update_bb_for_insn_chain (BB_HEAD (bb), BB_END (bb), bb);
559 16609194 : }
560 :
561 :
562 : /* Like active_insn_p, except keep the return value use or clobber around
563 : even after reload. */
564 :
565 : static bool
566 325084745 : flow_active_insn_p (const rtx_insn *insn)
567 : {
568 325084745 : if (active_insn_p (insn))
569 : return true;
570 :
571 : /* A clobber of the function return value exists for buggy
572 : programs that fail to return a value. Its effect is to
573 : keep the return value from being live across the entire
574 : function. If we allow it to be skipped, we introduce the
575 : possibility for register lifetime confusion.
576 : Similarly, keep a USE of the function return value, otherwise
577 : the USE is dropped and we could fail to thread jump if USE
578 : appears on some paths and not on others, see PR90257. */
579 198864499 : if ((GET_CODE (PATTERN (insn)) == CLOBBER
580 198797838 : || GET_CODE (PATTERN (insn)) == USE)
581 650375 : && REG_P (XEXP (PATTERN (insn), 0))
582 199508338 : && REG_FUNCTION_VALUE_P (XEXP (PATTERN (insn), 0)))
583 581481 : return true;
584 :
585 : return false;
586 : }
587 :
588 : /* Return true if the block has no effect and only forwards control flow to
589 : its single destination. */
590 :
591 : bool
592 313740539 : contains_no_active_insn_p (const_basic_block bb)
593 : {
594 313740539 : rtx_insn *insn;
595 :
596 313740539 : if (bb == EXIT_BLOCK_PTR_FOR_FN (cfun)
597 313740539 : || bb == ENTRY_BLOCK_PTR_FOR_FN (cfun)
598 441177986 : || !single_succ_p (bb)
599 459202934 : || (single_succ_edge (bb)->flags & EDGE_FAKE) != 0)
600 : return false;
601 :
602 556213978 : for (insn = BB_HEAD (bb); insn != BB_END (bb); insn = NEXT_INSN (insn))
603 510284777 : if (INSN_P (insn) && flow_active_insn_p (insn))
604 : return false;
605 :
606 45929201 : return (!INSN_P (insn)
607 35503088 : || (JUMP_P (insn) && simplejump_p (insn))
608 74165065 : || !flow_active_insn_p (insn));
609 : }
610 :
611 : /* Likewise, but protect loop latches, headers and preheaders. */
612 : /* FIXME: Make this a cfg hook. */
613 :
614 : bool
615 313740539 : forwarder_block_p (const_basic_block bb)
616 : {
617 313740539 : if (!contains_no_active_insn_p (bb))
618 : return false;
619 :
620 : /* Protect loop latches, headers and preheaders. */
621 18024948 : if (current_loops)
622 : {
623 8949553 : basic_block dest;
624 8949553 : if (bb->loop_father->header == bb)
625 : return false;
626 8859665 : dest = EDGE_SUCC (bb, 0)->dest;
627 8859665 : if (dest->loop_father->header == dest)
628 1102367 : return false;
629 : }
630 :
631 : return true;
632 : }
633 :
634 : /* Return nonzero if we can reach target from src by falling through. */
635 : /* FIXME: Make this a cfg hook, the result is only valid in cfgrtl mode. */
636 :
637 : bool
638 44333555 : can_fallthru (basic_block src, basic_block target)
639 : {
640 44333555 : rtx_insn *insn = BB_END (src);
641 44333555 : rtx_insn *insn2;
642 44333555 : edge e;
643 44333555 : edge_iterator ei;
644 :
645 44333555 : if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
646 : return true;
647 42966953 : if (src->next_bb != target)
648 : return false;
649 :
650 : /* ??? Later we may add code to move jump tables offline. */
651 17381721 : if (tablejump_p (insn, NULL, NULL))
652 : return false;
653 :
654 47239384 : FOR_EACH_EDGE (e, ei, src->succs)
655 29857663 : if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
656 0 : && e->flags & EDGE_FALLTHRU)
657 : return false;
658 :
659 17381721 : insn2 = BB_HEAD (target);
660 17381721 : if (!active_insn_p (insn2))
661 17381721 : insn2 = next_active_insn (insn2);
662 :
663 17381721 : return next_active_insn (insn) == insn2;
664 : }
665 :
666 : /* Return nonzero if we could reach target from src by falling through,
667 : if the target was made adjacent. If we already have a fall-through
668 : edge to the exit block, we can't do that. */
669 : static bool
670 2280795 : could_fall_through (basic_block src, basic_block target)
671 : {
672 2280795 : edge e;
673 2280795 : edge_iterator ei;
674 :
675 2280795 : if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
676 : return true;
677 6842385 : FOR_EACH_EDGE (e, ei, src->succs)
678 4561590 : if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
679 0 : && e->flags & EDGE_FALLTHRU)
680 : return 0;
681 : return true;
682 : }
683 :
684 : /* Return the NOTE_INSN_BASIC_BLOCK of BB. */
685 : rtx_note *
686 63830256 : bb_note (basic_block bb)
687 : {
688 63830256 : rtx_insn *note;
689 :
690 63830256 : note = BB_HEAD (bb);
691 63830256 : if (LABEL_P (note))
692 30751869 : note = NEXT_INSN (note);
693 :
694 63830256 : gcc_assert (NOTE_INSN_BASIC_BLOCK_P (note));
695 63830256 : return as_a <rtx_note *> (note);
696 : }
697 :
698 : /* Return the INSN immediately following the NOTE_INSN_BASIC_BLOCK
699 : note associated with the BLOCK. */
700 :
701 : static rtx_insn *
702 8036 : first_insn_after_basic_block_note (basic_block block)
703 : {
704 8036 : rtx_insn *insn;
705 :
706 : /* Get the first instruction in the block. */
707 8036 : insn = BB_HEAD (block);
708 :
709 8036 : if (insn == NULL_RTX)
710 : return NULL;
711 8036 : if (LABEL_P (insn))
712 8034 : insn = NEXT_INSN (insn);
713 8036 : gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn));
714 :
715 8036 : return NEXT_INSN (insn);
716 : }
717 :
718 : /* Creates a new basic block just after basic block BB by splitting
719 : everything after specified instruction INSNP. */
720 :
721 : static basic_block
722 2994895 : rtl_split_block (basic_block bb, void *insnp)
723 : {
724 2994895 : basic_block new_bb;
725 2994895 : rtx_insn *insn = (rtx_insn *) insnp;
726 2994895 : edge e;
727 2994895 : edge_iterator ei;
728 :
729 2994895 : if (!insn)
730 : {
731 8036 : insn = first_insn_after_basic_block_note (bb);
732 :
733 8036 : if (insn)
734 : {
735 8014 : rtx_insn *next = insn;
736 :
737 8014 : insn = PREV_INSN (insn);
738 :
739 : /* If the block contains only debug insns, insn would have
740 : been NULL in a non-debug compilation, and then we'd end
741 : up emitting a DELETED note. For -fcompare-debug
742 : stability, emit the note too. */
743 8014 : if (insn != BB_END (bb)
744 7769 : && DEBUG_INSN_P (next)
745 494 : && DEBUG_INSN_P (BB_END (bb)))
746 : {
747 330 : while (next != BB_END (bb) && DEBUG_INSN_P (next))
748 242 : next = NEXT_INSN (next);
749 :
750 88 : if (next == BB_END (bb))
751 87 : emit_note_after (NOTE_INSN_DELETED, next);
752 : }
753 : }
754 : else
755 22 : insn = get_last_insn ();
756 : }
757 :
758 : /* We probably should check type of the insn so that we do not create
759 : inconsistent cfg. It is checked in verify_flow_info anyway, so do not
760 : bother. */
761 2994895 : if (insn == BB_END (bb))
762 267 : emit_note_after (NOTE_INSN_DELETED, insn);
763 :
764 : /* Create the new basic block. */
765 2994895 : new_bb = create_basic_block (NEXT_INSN (insn), BB_END (bb), bb);
766 2994895 : BB_COPY_PARTITION (new_bb, bb);
767 2994895 : BB_END (bb) = insn;
768 :
769 : /* Redirect the outgoing edges. */
770 2994895 : new_bb->succs = bb->succs;
771 2994895 : bb->succs = NULL;
772 8179137 : FOR_EACH_EDGE (e, ei, new_bb->succs)
773 5184242 : e->src = new_bb;
774 :
775 : /* The new block starts off being dirty. */
776 2994895 : df_set_bb_dirty (bb);
777 2994895 : return new_bb;
778 : }
779 :
780 : /* Return true if LOC1 and LOC2 are equivalent for
781 : unique_locus_on_edge_between_p purposes. */
782 :
783 : static bool
784 1375369 : loc_equal (location_t loc1, location_t loc2)
785 : {
786 1375369 : if (loc1 == loc2)
787 : return true;
788 :
789 643896 : expanded_location loce1 = expand_location (loc1);
790 643896 : expanded_location loce2 = expand_location (loc2);
791 :
792 643896 : if (loce1.line != loce2.line
793 428589 : || loce1.column != loce2.column
794 307013 : || loce1.data != loce2.data)
795 : return false;
796 268452 : if (loce1.file == loce2.file)
797 : return true;
798 0 : return (loce1.file != NULL
799 0 : && loce2.file != NULL
800 0 : && filename_cmp (loce1.file, loce2.file) == 0);
801 : }
802 :
803 : /* Return true if the single edge between blocks A and B is the only place
804 : in RTL which holds some unique locus. */
805 :
806 : static bool
807 1106537 : unique_locus_on_edge_between_p (basic_block a, basic_block b)
808 : {
809 1106537 : const location_t goto_locus = EDGE_SUCC (a, 0)->goto_locus;
810 1106537 : rtx_insn *insn, *end;
811 :
812 1106537 : if (LOCATION_LOCUS (goto_locus) == UNKNOWN_LOCATION)
813 : return false;
814 :
815 : /* First scan block A backward. */
816 500699 : insn = BB_END (a);
817 500699 : end = PREV_INSN (BB_HEAD (a));
818 1160726 : while (insn != end && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn)))
819 159328 : insn = PREV_INSN (insn);
820 :
821 500699 : if (insn != end && loc_equal (INSN_LOCATION (insn), goto_locus))
822 : return false;
823 :
824 : /* Then scan block B forward. */
825 181725 : insn = BB_HEAD (b);
826 181725 : if (insn)
827 : {
828 172227 : end = NEXT_INSN (BB_END (b));
829 345788 : while (insn != end && !NONDEBUG_INSN_P (insn))
830 1334 : insn = NEXT_INSN (insn);
831 :
832 171983 : if (insn != end && INSN_HAS_LOCATION (insn)
833 343450 : && loc_equal (INSN_LOCATION (insn), goto_locus))
834 : return false;
835 : }
836 :
837 : return true;
838 : }
839 :
840 : /* If the single edge between blocks A and B is the only place in RTL which
841 : holds some unique locus, emit a nop with that locus between the blocks. */
842 :
843 : static void
844 1106537 : emit_nop_for_unique_locus_between (basic_block a, basic_block b)
845 : {
846 1106537 : if (!unique_locus_on_edge_between_p (a, b))
847 : return;
848 :
849 22040 : BB_END (a) = emit_insn_after_noloc (gen_nop (), BB_END (a), a);
850 22040 : INSN_LOCATION (BB_END (a)) = EDGE_SUCC (a, 0)->goto_locus;
851 : }
852 :
853 : /* Blocks A and B are to be merged into a single block A. The insns
854 : are already contiguous. */
855 :
856 : static void
857 3725640 : rtl_merge_blocks (basic_block a, basic_block b)
858 : {
859 : /* If B is a forwarder block whose outgoing edge has no location, we'll
860 : propagate the locus of the edge between A and B onto it. */
861 3725640 : const bool forward_edge_locus
862 3725640 : = (b->flags & BB_FORWARDER_BLOCK) != 0
863 3725640 : && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION;
864 3725640 : rtx_insn *b_head = BB_HEAD (b), *b_end = BB_END (b), *a_end = BB_END (a);
865 3725640 : rtx_insn *del_first = NULL, *del_last = NULL;
866 3725640 : rtx_insn *b_debug_start = b_end, *b_debug_end = b_end;
867 3725640 : bool b_empty = false;
868 :
869 3725640 : if (dump_file)
870 851 : fprintf (dump_file, "Merging block %d into block %d...\n", b->index,
871 : a->index);
872 :
873 4177131 : while (DEBUG_INSN_P (b_end))
874 451491 : b_end = PREV_INSN (b_debug_start = b_end);
875 :
876 : /* If there was a CODE_LABEL beginning B, delete it. */
877 3725640 : if (LABEL_P (b_head))
878 : {
879 : /* Detect basic blocks with nothing but a label. This can happen
880 : in particular at the end of a function. */
881 1737014 : if (b_head == b_end)
882 0 : b_empty = true;
883 :
884 1737014 : del_first = del_last = b_head;
885 1737014 : b_head = NEXT_INSN (b_head);
886 : }
887 :
888 : /* Delete the basic block note and handle blocks containing just that
889 : note. */
890 3725640 : if (NOTE_INSN_BASIC_BLOCK_P (b_head))
891 : {
892 3725640 : if (b_head == b_end)
893 703721 : b_empty = true;
894 3725640 : if (! del_last)
895 1988626 : del_first = b_head;
896 :
897 3725640 : del_last = b_head;
898 3725640 : b_head = NEXT_INSN (b_head);
899 : }
900 :
901 : /* If there was a jump out of A, delete it. */
902 3725640 : if (JUMP_P (a_end))
903 : {
904 52609 : rtx_insn *prev;
905 :
906 53694 : for (prev = PREV_INSN (a_end); ; prev = PREV_INSN (prev))
907 53694 : if (!NOTE_P (prev)
908 1107 : || NOTE_INSN_BASIC_BLOCK_P (prev)
909 1085 : || prev == BB_HEAD (a))
910 : break;
911 :
912 : del_first = a_end;
913 :
914 : a_end = PREV_INSN (del_first);
915 : }
916 3673031 : else if (BARRIER_P (NEXT_INSN (a_end)))
917 0 : del_first = NEXT_INSN (a_end);
918 :
919 : /* Delete everything marked above as well as crap that might be
920 : hanging out between the two blocks. */
921 3725640 : BB_END (a) = a_end;
922 3725640 : BB_HEAD (b) = b_empty ? NULL : b_head;
923 3725640 : delete_insn_chain (del_first, del_last, true);
924 :
925 : /* If not optimizing, preserve the locus of the single edge between
926 : blocks A and B if necessary by emitting a nop. */
927 3725640 : if (!optimize
928 1362283 : && !forward_edge_locus
929 4832999 : && !DECL_IGNORED_P (current_function_decl))
930 : {
931 1104357 : emit_nop_for_unique_locus_between (a, b);
932 1104357 : a_end = BB_END (a);
933 : }
934 :
935 : /* Reassociate the insns of B with A. */
936 3725640 : if (!b_empty)
937 : {
938 3021919 : update_bb_for_insn_chain (a_end, b_debug_end, a);
939 :
940 3021919 : BB_END (a) = b_debug_end;
941 3021919 : BB_HEAD (b) = NULL;
942 : }
943 703721 : else if (b_end != b_debug_end)
944 : {
945 : /* Move any deleted labels and other notes between the end of A
946 : and the debug insns that make up B after the debug insns,
947 : bringing the debug insns into A while keeping the notes after
948 : the end of A. */
949 21929 : if (NEXT_INSN (a_end) != b_debug_start)
950 138 : reorder_insns_nobb (NEXT_INSN (a_end), PREV_INSN (b_debug_start),
951 : b_debug_end);
952 21929 : update_bb_for_insn_chain (b_debug_start, b_debug_end, a);
953 21929 : BB_END (a) = b_debug_end;
954 : }
955 :
956 3725640 : df_bb_delete (b->index);
957 :
958 3725640 : if (forward_edge_locus)
959 682727 : EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus;
960 :
961 3725640 : if (dump_file)
962 851 : fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index);
963 3725640 : }
964 :
965 :
966 : /* Return true when block A and B can be merged. */
967 :
968 : static bool
969 62 : rtl_can_merge_blocks (basic_block a, basic_block b)
970 : {
971 : /* If we are partitioning hot/cold basic blocks, we don't want to
972 : mess up unconditional or indirect jumps that cross between hot
973 : and cold sections.
974 :
975 : Basic block partitioning may result in some jumps that appear to
976 : be optimizable (or blocks that appear to be mergeable), but which really
977 : must be left untouched (they are required to make it safely across
978 : partition boundaries). See the comments at the top of
979 : bb-reorder.cc:partition_hot_cold_basic_blocks for complete details. */
980 :
981 62 : if (BB_PARTITION (a) != BB_PARTITION (b))
982 : return false;
983 :
984 : /* Protect the loop latches. */
985 62 : if (current_loops && b->loop_father->latch == b)
986 : return false;
987 :
988 : /* There must be exactly one edge in between the blocks. */
989 62 : return (single_succ_p (a)
990 61 : && single_succ (a) == b
991 51 : && single_pred_p (b)
992 51 : && a != b
993 : /* Must be simple edge. */
994 51 : && !(single_succ_edge (a)->flags & EDGE_COMPLEX)
995 51 : && a->next_bb == b
996 51 : && a != ENTRY_BLOCK_PTR_FOR_FN (cfun)
997 51 : && b != EXIT_BLOCK_PTR_FOR_FN (cfun)
998 : /* If the jump insn has side effects,
999 : we can't kill the edge. */
1000 113 : && (!JUMP_P (BB_END (a))
1001 0 : || (reload_completed
1002 0 : ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a)))));
1003 : }
1004 :
1005 : /* Return the label in the head of basic block BLOCK. Create one if it doesn't
1006 : exist. */
1007 :
1008 : rtx_code_label *
1009 15410580 : block_label (basic_block block)
1010 : {
1011 15410580 : if (block == EXIT_BLOCK_PTR_FOR_FN (cfun))
1012 : return NULL;
1013 :
1014 15360303 : if (!LABEL_P (BB_HEAD (block)))
1015 : {
1016 5664059 : BB_HEAD (block) = emit_label_before (gen_label_rtx (), BB_HEAD (block));
1017 : }
1018 :
1019 15360303 : return as_a <rtx_code_label *> (BB_HEAD (block));
1020 : }
1021 :
1022 : /* Remove all barriers from BB_FOOTER of a BB. */
1023 :
1024 : static void
1025 3763151 : remove_barriers_from_footer (basic_block bb)
1026 : {
1027 3763151 : rtx_insn *insn = BB_FOOTER (bb);
1028 :
1029 : /* Remove barriers but keep jumptables. */
1030 7280940 : while (insn)
1031 : {
1032 3517789 : if (BARRIER_P (insn))
1033 : {
1034 3517769 : if (PREV_INSN (insn))
1035 16 : SET_NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn);
1036 : else
1037 3517753 : BB_FOOTER (bb) = NEXT_INSN (insn);
1038 3517769 : if (NEXT_INSN (insn))
1039 61744 : SET_PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn);
1040 : }
1041 3517789 : if (LABEL_P (insn))
1042 : return;
1043 3517789 : insn = NEXT_INSN (insn);
1044 : }
1045 : }
1046 :
1047 : /* Attempt to perform edge redirection by replacing possibly complex jump
1048 : instruction by unconditional jump or removing jump completely. This can
1049 : apply only if all edges now point to the same block. The parameters and
1050 : return values are equivalent to redirect_edge_and_branch. */
1051 :
1052 : edge
1053 48024744 : try_redirect_by_replacing_jump (edge e, basic_block target, bool in_cfglayout)
1054 : {
1055 48024744 : basic_block src = e->src;
1056 48024744 : rtx_insn *insn = BB_END (src);
1057 48024744 : rtx set;
1058 48024744 : bool fallthru = false;
1059 :
1060 : /* If we are partitioning hot/cold basic blocks, we don't want to
1061 : mess up unconditional or indirect jumps that cross between hot
1062 : and cold sections.
1063 :
1064 : Basic block partitioning may result in some jumps that appear to
1065 : be optimizable (or blocks that appear to be mergeable), but which really
1066 : must be left untouched (they are required to make it safely across
1067 : partition boundaries). See the comments at the top of
1068 : bb-reorder.cc:partition_hot_cold_basic_blocks for complete details. */
1069 :
1070 48024744 : if (BB_PARTITION (src) != BB_PARTITION (target))
1071 : return NULL;
1072 :
1073 : /* We can replace or remove a complex jump only when we have exactly
1074 : two edges. Also, if we have exactly one outgoing edge, we can
1075 : redirect that. */
1076 47967914 : if (EDGE_COUNT (src->succs) >= 3
1077 : /* Verify that all targets will be TARGET. Specifically, the
1078 : edge that is not E must also go to TARGET. */
1079 47967914 : || (EDGE_COUNT (src->succs) == 2
1080 17901093 : && EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target))
1081 : return NULL;
1082 :
1083 30194763 : if (!onlyjump_p (insn))
1084 : return NULL;
1085 28708030 : if ((!optimize || reload_completed) && tablejump_p (insn, NULL, NULL))
1086 : return NULL;
1087 :
1088 : /* Avoid removing branch with side effects. */
1089 28707913 : set = single_set (insn);
1090 28707913 : if (!set || side_effects_p (set))
1091 0 : return NULL;
1092 :
1093 : /* See if we can create the fallthru edge. */
1094 28707913 : if (in_cfglayout || can_fallthru (src, target))
1095 : {
1096 4614829 : if (dump_file)
1097 778 : fprintf (dump_file, "Removing jump %i.\n", INSN_UID (insn));
1098 4614829 : fallthru = true;
1099 :
1100 : /* Selectively unlink whole insn chain. */
1101 4614829 : if (in_cfglayout)
1102 : {
1103 3763150 : delete_insn_chain (insn, BB_END (src), false);
1104 3763150 : remove_barriers_from_footer (src);
1105 : }
1106 : else
1107 851679 : delete_insn_chain (insn, PREV_INSN (BB_HEAD (target)), false);
1108 : }
1109 :
1110 : /* If this already is simplejump, redirect it. */
1111 24093084 : else if (simplejump_p (insn))
1112 : {
1113 24091085 : if (e->dest == target)
1114 : return NULL;
1115 424995 : if (dump_file)
1116 37 : fprintf (dump_file, "Redirecting jump %i from %i to %i.\n",
1117 37 : INSN_UID (insn), e->dest->index, target->index);
1118 424995 : if (!redirect_jump (as_a <rtx_jump_insn *> (insn),
1119 424995 : block_label (target), 0))
1120 : {
1121 0 : gcc_assert (target == EXIT_BLOCK_PTR_FOR_FN (cfun));
1122 : return NULL;
1123 : }
1124 : }
1125 :
1126 : /* Cannot do anything for target exit block. */
1127 1999 : else if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
1128 : return NULL;
1129 :
1130 : /* Or replace possibly complicated jump insn by simple jump insn. */
1131 : else
1132 : {
1133 1999 : rtx_code_label *target_label = block_label (target);
1134 1999 : rtx_insn *barrier;
1135 1999 : rtx_insn *label;
1136 1999 : rtx_jump_table_data *table;
1137 :
1138 1999 : emit_jump_insn_after_noloc (targetm.gen_jump (target_label), insn);
1139 1999 : JUMP_LABEL (BB_END (src)) = target_label;
1140 1999 : LABEL_NUSES (target_label)++;
1141 1999 : if (dump_file)
1142 0 : fprintf (dump_file, "Replacing insn %i by jump %i\n",
1143 0 : INSN_UID (insn), INSN_UID (BB_END (src)));
1144 :
1145 :
1146 1999 : delete_insn_chain (insn, insn, false);
1147 :
1148 : /* Recognize a tablejump that we are converting to a
1149 : simple jump and remove its associated CODE_LABEL
1150 : and ADDR_VEC or ADDR_DIFF_VEC. */
1151 1999 : if (tablejump_p (insn, &label, &table))
1152 2 : delete_insn_chain (label, table, false);
1153 :
1154 1999 : barrier = next_nonnote_nondebug_insn (BB_END (src));
1155 1999 : if (!barrier || !BARRIER_P (barrier))
1156 1866 : emit_barrier_after (BB_END (src));
1157 : else
1158 : {
1159 133 : if (barrier != NEXT_INSN (BB_END (src)))
1160 : {
1161 : /* Move the jump before barrier so that the notes
1162 : which originally were or were created before jump table are
1163 : inside the basic block. */
1164 0 : rtx_insn *new_insn = BB_END (src);
1165 :
1166 0 : update_bb_for_insn_chain (NEXT_INSN (BB_END (src)),
1167 : PREV_INSN (barrier), src);
1168 :
1169 0 : SET_NEXT_INSN (PREV_INSN (new_insn)) = NEXT_INSN (new_insn);
1170 0 : SET_PREV_INSN (NEXT_INSN (new_insn)) = PREV_INSN (new_insn);
1171 :
1172 0 : SET_NEXT_INSN (new_insn) = barrier;
1173 0 : SET_NEXT_INSN (PREV_INSN (barrier)) = new_insn;
1174 :
1175 0 : SET_PREV_INSN (new_insn) = PREV_INSN (barrier);
1176 0 : SET_PREV_INSN (barrier) = new_insn;
1177 : }
1178 : }
1179 : }
1180 :
1181 : /* Keep only one edge out and set proper flags. */
1182 5041823 : if (!single_succ_p (src))
1183 147503 : remove_edge (e);
1184 5041823 : gcc_assert (single_succ_p (src));
1185 :
1186 5041823 : e = single_succ_edge (src);
1187 5041823 : if (fallthru)
1188 4614829 : e->flags = EDGE_FALLTHRU;
1189 : else
1190 426994 : e->flags = 0;
1191 :
1192 5041823 : e->probability = profile_probability::always ();
1193 :
1194 5041823 : if (e->dest != target)
1195 640306 : redirect_edge_succ (e, target);
1196 : return e;
1197 : }
1198 :
1199 : /* Subroutine of redirect_branch_edge that tries to patch the jump
1200 : instruction INSN so that it reaches block NEW. Do this
1201 : only when it originally reached block OLD. Return true if this
1202 : worked or the original target wasn't OLD, return false if redirection
1203 : doesn't work. */
1204 :
1205 : static bool
1206 6834944 : patch_jump_insn (rtx_insn *insn, rtx_insn *old_label, basic_block new_bb)
1207 : {
1208 6834944 : rtx_jump_table_data *table;
1209 6834944 : rtx tmp;
1210 : /* Recognize a tablejump and adjust all matching cases. */
1211 6834944 : if (tablejump_p (insn, NULL, &table))
1212 : {
1213 15870 : rtvec vec;
1214 15870 : int j;
1215 15870 : rtx_code_label *new_label = block_label (new_bb);
1216 :
1217 15870 : if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun))
1218 : return false;
1219 15870 : vec = table->get_labels ();
1220 :
1221 380294 : for (j = GET_NUM_ELEM (vec) - 1; j >= 0; --j)
1222 364424 : if (XEXP (RTVEC_ELT (vec, j), 0) == old_label)
1223 : {
1224 58457 : RTVEC_ELT (vec, j) = gen_rtx_LABEL_REF (Pmode, new_label);
1225 52200 : --LABEL_NUSES (old_label);
1226 52200 : ++LABEL_NUSES (new_label);
1227 : }
1228 :
1229 : /* Handle casesi dispatch insns. */
1230 15870 : if ((tmp = tablejump_casesi_pattern (insn)) != NULL_RTX
1231 15870 : && label_ref_label (XEXP (SET_SRC (tmp), 2)) == old_label)
1232 : {
1233 0 : XEXP (SET_SRC (tmp), 2) = gen_rtx_LABEL_REF (Pmode,
1234 : new_label);
1235 0 : --LABEL_NUSES (old_label);
1236 0 : ++LABEL_NUSES (new_label);
1237 : }
1238 : }
1239 6819074 : else if ((tmp = extract_asm_operands (PATTERN (insn))) != NULL)
1240 : {
1241 411 : int i, n = ASM_OPERANDS_LABEL_LENGTH (tmp);
1242 411 : rtx note;
1243 :
1244 411 : if (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun))
1245 : return false;
1246 411 : rtx_code_label *new_label = block_label (new_bb);
1247 :
1248 1117 : for (i = 0; i < n; ++i)
1249 : {
1250 706 : rtx old_ref = ASM_OPERANDS_LABEL (tmp, i);
1251 706 : gcc_assert (GET_CODE (old_ref) == LABEL_REF);
1252 706 : if (XEXP (old_ref, 0) == old_label)
1253 : {
1254 818 : ASM_OPERANDS_LABEL (tmp, i)
1255 409 : = gen_rtx_LABEL_REF (Pmode, new_label);
1256 409 : --LABEL_NUSES (old_label);
1257 409 : ++LABEL_NUSES (new_label);
1258 : }
1259 : }
1260 :
1261 411 : if (JUMP_LABEL (insn) == old_label)
1262 : {
1263 305 : JUMP_LABEL (insn) = new_label;
1264 305 : note = find_reg_note (insn, REG_LABEL_TARGET, new_label);
1265 305 : if (note)
1266 0 : remove_note (insn, note);
1267 : }
1268 : else
1269 : {
1270 106 : note = find_reg_note (insn, REG_LABEL_TARGET, old_label);
1271 106 : if (note)
1272 99 : remove_note (insn, note);
1273 106 : if (JUMP_LABEL (insn) != new_label
1274 106 : && !find_reg_note (insn, REG_LABEL_TARGET, new_label))
1275 99 : add_reg_note (insn, REG_LABEL_TARGET, new_label);
1276 : }
1277 822 : while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label))
1278 411 : != NULL_RTX)
1279 0 : XEXP (note, 0) = new_label;
1280 : }
1281 : else
1282 : {
1283 : /* ?? We may play the games with moving the named labels from
1284 : one basic block to the other in case only one computed_jump is
1285 : available. */
1286 6818663 : if (computed_jump_p (insn)
1287 : /* A return instruction can't be redirected. */
1288 6818663 : || returnjump_p (insn))
1289 0 : return false;
1290 :
1291 6818663 : if (!currently_expanding_to_rtl || JUMP_LABEL (insn) == old_label)
1292 : {
1293 : /* If the insn doesn't go where we think, we're confused. */
1294 6794332 : gcc_assert (JUMP_LABEL (insn) == old_label);
1295 :
1296 : /* If the substitution doesn't succeed, die. This can happen
1297 : if the back end emitted unrecognizable instructions or if
1298 : target is exit block on some arches. Or for crossing
1299 : jumps. */
1300 6794332 : if (!redirect_jump (as_a <rtx_jump_insn *> (insn),
1301 6794332 : block_label (new_bb), 0))
1302 : {
1303 0 : gcc_assert (new_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)
1304 : || CROSSING_JUMP_P (insn));
1305 : return false;
1306 : }
1307 : }
1308 : }
1309 : return true;
1310 : }
1311 :
1312 :
1313 : /* Redirect edge representing branch of (un)conditional jump or tablejump,
1314 : NULL on failure */
1315 : static edge
1316 14623948 : redirect_branch_edge (edge e, basic_block target)
1317 : {
1318 14623948 : rtx_insn *old_label = BB_HEAD (e->dest);
1319 14623948 : basic_block src = e->src;
1320 14623948 : rtx_insn *insn = BB_END (src);
1321 :
1322 : /* We can only redirect non-fallthru edges of jump insn. */
1323 14623948 : if (e->flags & EDGE_FALLTHRU)
1324 : return NULL;
1325 6799090 : else if (!JUMP_P (insn) && !currently_expanding_to_rtl)
1326 : return NULL;
1327 :
1328 6799090 : if (!currently_expanding_to_rtl)
1329 : {
1330 6363248 : if (!patch_jump_insn (as_a <rtx_jump_insn *> (insn), old_label, target))
1331 : return NULL;
1332 : }
1333 : else
1334 : /* When expanding this BB might actually contain multiple
1335 : jumps (i.e. not yet split by find_many_sub_basic_blocks).
1336 : Redirect all of those that match our label. */
1337 7055707 : FOR_BB_INSNS (src, insn)
1338 6619865 : if (JUMP_P (insn) && !patch_jump_insn (as_a <rtx_jump_insn *> (insn),
1339 : old_label, target))
1340 : return NULL;
1341 :
1342 6799090 : if (dump_file)
1343 797 : fprintf (dump_file, "Edge %i->%i redirected to %i\n",
1344 797 : e->src->index, e->dest->index, target->index);
1345 :
1346 6799090 : if (e->dest != target)
1347 6799090 : e = redirect_edge_succ_nodup (e, target);
1348 :
1349 : return e;
1350 : }
1351 :
1352 : /* Called when edge E has been redirected to a new destination,
1353 : in order to update the region crossing flag on the edge and
1354 : jump. */
1355 :
1356 : static void
1357 18252825 : fixup_partition_crossing (edge e)
1358 : {
1359 18252825 : if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun) || e->dest
1360 18252825 : == EXIT_BLOCK_PTR_FOR_FN (cfun))
1361 : return;
1362 : /* If we redirected an existing edge, it may already be marked
1363 : crossing, even though the new src is missing a reg crossing note.
1364 : But make sure reg crossing note doesn't already exist before
1365 : inserting. */
1366 18251803 : if (BB_PARTITION (e->src) != BB_PARTITION (e->dest))
1367 : {
1368 112433 : e->flags |= EDGE_CROSSING;
1369 112433 : if (JUMP_P (BB_END (e->src)))
1370 112433 : CROSSING_JUMP_P (BB_END (e->src)) = 1;
1371 : }
1372 18139370 : else if (BB_PARTITION (e->src) == BB_PARTITION (e->dest))
1373 : {
1374 18139370 : e->flags &= ~EDGE_CROSSING;
1375 : /* Remove the section crossing note from jump at end of
1376 : src if it exists, and if no other successors are
1377 : still crossing. */
1378 18139370 : if (JUMP_P (BB_END (e->src)) && CROSSING_JUMP_P (BB_END (e->src)))
1379 : {
1380 196247 : bool has_crossing_succ = false;
1381 196247 : edge e2;
1382 196247 : edge_iterator ei;
1383 326346 : FOR_EACH_EDGE (e2, ei, e->src->succs)
1384 : {
1385 273357 : has_crossing_succ |= (e2->flags & EDGE_CROSSING);
1386 273357 : if (has_crossing_succ)
1387 : break;
1388 : }
1389 196247 : if (!has_crossing_succ)
1390 52989 : CROSSING_JUMP_P (BB_END (e->src)) = 0;
1391 : }
1392 : }
1393 : }
1394 :
1395 : /* Called when block BB has been reassigned to the cold partition,
1396 : because it is now dominated by another cold block,
1397 : to ensure that the region crossing attributes are updated. */
1398 :
1399 : static void
1400 320 : fixup_new_cold_bb (basic_block bb)
1401 : {
1402 320 : edge e;
1403 320 : edge_iterator ei;
1404 :
1405 : /* This is called when a hot bb is found to now be dominated
1406 : by a cold bb and therefore needs to become cold. Therefore,
1407 : its preds will no longer be region crossing. Any non-dominating
1408 : preds that were previously hot would also have become cold
1409 : in the caller for the same region. Any preds that were previously
1410 : region-crossing will be adjusted in fixup_partition_crossing. */
1411 654 : FOR_EACH_EDGE (e, ei, bb->preds)
1412 : {
1413 334 : fixup_partition_crossing (e);
1414 : }
1415 :
1416 : /* Possibly need to make bb's successor edges region crossing,
1417 : or remove stale region crossing. */
1418 655 : FOR_EACH_EDGE (e, ei, bb->succs)
1419 : {
1420 : /* We can't have fall-through edges across partition boundaries.
1421 : Note that force_nonfallthru will do any necessary partition
1422 : boundary fixup by calling fixup_partition_crossing itself. */
1423 335 : if ((e->flags & EDGE_FALLTHRU)
1424 294 : && BB_PARTITION (bb) != BB_PARTITION (e->dest)
1425 270 : && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
1426 0 : force_nonfallthru (e);
1427 : else
1428 335 : fixup_partition_crossing (e);
1429 : }
1430 320 : }
1431 :
1432 : /* Attempt to change code to redirect edge E to TARGET. Don't do that on
1433 : expense of adding new instructions or reordering basic blocks.
1434 :
1435 : Function can be also called with edge destination equivalent to the TARGET.
1436 : Then it should try the simplifications and do nothing if none is possible.
1437 :
1438 : Return edge representing the branch if transformation succeeded. Return NULL
1439 : on failure.
1440 : We still return NULL in case E already destinated TARGET and we didn't
1441 : managed to simplify instruction stream. */
1442 :
1443 : static edge
1444 9997184 : rtl_redirect_edge_and_branch (edge e, basic_block target)
1445 : {
1446 9997184 : edge ret;
1447 9997184 : basic_block src = e->src;
1448 9997184 : basic_block dest = e->dest;
1449 :
1450 9997184 : if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
1451 : return NULL;
1452 :
1453 9997184 : if (dest == target)
1454 : return e;
1455 :
1456 9997179 : if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL)
1457 : {
1458 484460 : df_set_bb_dirty (src);
1459 484460 : fixup_partition_crossing (ret);
1460 484460 : return ret;
1461 : }
1462 :
1463 9512719 : ret = redirect_branch_edge (e, target);
1464 9512719 : if (!ret)
1465 : return NULL;
1466 :
1467 1687861 : df_set_bb_dirty (src);
1468 1687861 : fixup_partition_crossing (ret);
1469 1687861 : return ret;
1470 : }
1471 :
1472 : /* Emit a barrier after BB, into the footer if we are in CFGLAYOUT mode. */
1473 :
1474 : void
1475 5418344 : emit_barrier_after_bb (basic_block bb)
1476 : {
1477 5418344 : rtx_barrier *barrier = emit_barrier_after (BB_END (bb));
1478 5418344 : gcc_assert (current_ir_type () == IR_RTL_CFGRTL
1479 : || current_ir_type () == IR_RTL_CFGLAYOUT);
1480 5418344 : if (current_ir_type () == IR_RTL_CFGLAYOUT)
1481 : {
1482 73851 : rtx_insn *insn = unlink_insn_chain (barrier, barrier);
1483 :
1484 73851 : if (BB_FOOTER (bb))
1485 : {
1486 : rtx_insn *footer_tail = BB_FOOTER (bb);
1487 :
1488 2900 : while (NEXT_INSN (footer_tail))
1489 : footer_tail = NEXT_INSN (footer_tail);
1490 2900 : if (!BARRIER_P (footer_tail))
1491 : {
1492 0 : SET_NEXT_INSN (footer_tail) = insn;
1493 0 : SET_PREV_INSN (insn) = footer_tail;
1494 : }
1495 : }
1496 : else
1497 70951 : BB_FOOTER (bb) = insn;
1498 : }
1499 5418344 : }
1500 :
1501 : /* Like force_nonfallthru below, but additionally performs redirection
1502 : Used by redirect_edge_and_branch_force. JUMP_LABEL is used only
1503 : when redirecting to the EXIT_BLOCK, it is either ret_rtx or
1504 : simple_return_rtx, indicating which kind of returnjump to create.
1505 : It should be NULL otherwise. */
1506 :
1507 : basic_block
1508 5282879 : force_nonfallthru_and_redirect (edge e, basic_block target, rtx jump_label)
1509 : {
1510 5282879 : basic_block jump_block, new_bb = NULL, src = e->src;
1511 5282879 : rtx note;
1512 5282879 : edge new_edge;
1513 5282879 : int abnormal_edge_flags = 0;
1514 5282879 : bool asm_goto_edge = false;
1515 :
1516 : /* In the case the last instruction is conditional jump to the next
1517 : instruction, first redirect the jump itself and then continue
1518 : by creating a basic block afterwards to redirect fallthru edge. */
1519 5282879 : if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
1520 5282872 : && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
1521 5282872 : && any_condjump_p (BB_END (e->src))
1522 6084086 : && JUMP_LABEL (BB_END (e->src)) == BB_HEAD (e->dest))
1523 : {
1524 0 : rtx note;
1525 0 : edge b = unchecked_make_edge (e->src, target, 0);
1526 0 : bool redirected;
1527 :
1528 0 : redirected = redirect_jump (as_a <rtx_jump_insn *> (BB_END (e->src)),
1529 0 : block_label (target), 0);
1530 0 : gcc_assert (redirected);
1531 :
1532 0 : note = find_reg_note (BB_END (e->src), REG_BR_PROB, NULL_RTX);
1533 0 : if (note)
1534 : {
1535 0 : int prob = XINT (note, 0);
1536 :
1537 0 : b->probability = profile_probability::from_reg_br_prob_note (prob);
1538 0 : e->probability -= e->probability;
1539 : }
1540 : }
1541 :
1542 5282879 : if (e->flags & EDGE_ABNORMAL)
1543 : {
1544 : /* Irritating special case - fallthru edge to the same block as abnormal
1545 : edge.
1546 : We can't redirect abnormal edge, but we still can split the fallthru
1547 : one and create separate abnormal edge to original destination.
1548 : This allows bb-reorder to make such edge non-fallthru. */
1549 0 : gcc_assert (e->dest == target);
1550 0 : abnormal_edge_flags = e->flags & ~EDGE_FALLTHRU;
1551 0 : e->flags &= EDGE_FALLTHRU;
1552 : }
1553 : else
1554 : {
1555 5282879 : gcc_assert (e->flags & EDGE_FALLTHRU);
1556 5282879 : if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun))
1557 : {
1558 : /* We can't redirect the entry block. Create an empty block
1559 : at the start of the function which we use to add the new
1560 : jump. */
1561 7 : edge tmp;
1562 7 : edge_iterator ei;
1563 7 : bool found = false;
1564 :
1565 7 : basic_block bb = create_basic_block (BB_HEAD (e->dest), NULL,
1566 : ENTRY_BLOCK_PTR_FOR_FN (cfun));
1567 7 : bb->count = ENTRY_BLOCK_PTR_FOR_FN (cfun)->count;
1568 :
1569 : /* Make sure new block ends up in correct hot/cold section. */
1570 7 : BB_COPY_PARTITION (bb, e->dest);
1571 :
1572 : /* Change the existing edge's source to be the new block, and add
1573 : a new edge from the entry block to the new block. */
1574 7 : e->src = bb;
1575 7 : for (ei = ei_start (ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs);
1576 7 : (tmp = ei_safe_edge (ei)); )
1577 : {
1578 7 : if (tmp == e)
1579 : {
1580 7 : ENTRY_BLOCK_PTR_FOR_FN (cfun)->succs->unordered_remove (ei.index);
1581 7 : found = true;
1582 7 : break;
1583 : }
1584 : else
1585 0 : ei_next (&ei);
1586 : }
1587 :
1588 0 : gcc_assert (found);
1589 :
1590 7 : vec_safe_push (bb->succs, e);
1591 7 : make_single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun), bb,
1592 : EDGE_FALLTHRU);
1593 : }
1594 : }
1595 :
1596 : /* If e->src ends with asm goto, see if any of the ASM_OPERANDS_LABELs
1597 : don't point to the fallthru label. */
1598 5282879 : if (JUMP_P (BB_END (e->src))
1599 801352 : && target != EXIT_BLOCK_PTR_FOR_FN (cfun)
1600 800848 : && (e->flags & EDGE_FALLTHRU)
1601 6083727 : && (note = extract_asm_operands (PATTERN (BB_END (e->src)))))
1602 : {
1603 145 : int n = ASM_OPERANDS_LABEL_LENGTH (note);
1604 :
1605 261 : for (int i = 0; i < n; ++i)
1606 184 : if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest))
1607 : {
1608 : asm_goto_edge = true;
1609 : break;
1610 : }
1611 : }
1612 :
1613 5282879 : if (EDGE_COUNT (e->src->succs) >= 2 || abnormal_edge_flags || asm_goto_edge)
1614 : {
1615 993122 : rtx_insn *new_head;
1616 993122 : profile_count count = e->count ();
1617 993122 : profile_probability probability = e->probability;
1618 : /* Create the new structures. */
1619 :
1620 : /* If the old block ended with a tablejump, skip its table
1621 : by searching forward from there. Otherwise start searching
1622 : forward from the last instruction of the old block. */
1623 993122 : rtx_jump_table_data *table;
1624 993122 : if (tablejump_p (BB_END (e->src), NULL, &table))
1625 0 : new_head = table;
1626 : else
1627 993122 : new_head = BB_END (e->src);
1628 993122 : new_head = NEXT_INSN (new_head);
1629 :
1630 993122 : jump_block = create_basic_block (new_head, NULL, e->src);
1631 993122 : jump_block->count = count;
1632 :
1633 : /* Make sure new block ends up in correct hot/cold section. */
1634 :
1635 993122 : BB_COPY_PARTITION (jump_block, e->src);
1636 :
1637 : /* Wire edge in. */
1638 993122 : new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU);
1639 993122 : new_edge->probability = probability;
1640 :
1641 : /* Redirect old edge. */
1642 993122 : redirect_edge_pred (e, jump_block);
1643 993122 : e->probability = profile_probability::always ();
1644 :
1645 : /* If e->src was previously region crossing, it no longer is
1646 : and the reg crossing note should be removed. */
1647 993122 : fixup_partition_crossing (new_edge);
1648 :
1649 : /* If asm goto has any label refs to e->dest, change them to point
1650 : to jump_block instead. */
1651 993122 : if (asm_goto_edge)
1652 : {
1653 68 : int n = ASM_OPERANDS_LABEL_LENGTH (note);
1654 :
1655 174 : for (int i = 0; i < n; ++i)
1656 106 : if (XEXP (ASM_OPERANDS_LABEL (note, i), 0) == BB_HEAD (e->dest))
1657 : {
1658 69 : LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))--;
1659 69 : XEXP (ASM_OPERANDS_LABEL (note, i), 0)
1660 69 : = block_label (jump_block);
1661 69 : LABEL_NUSES (XEXP (ASM_OPERANDS_LABEL (note, i), 0))++;
1662 : }
1663 :
1664 68 : rtx_insn *insn = BB_END (new_edge->src);
1665 68 : rtx note;
1666 68 : rtx_insn *old_label = BB_HEAD (e->dest);
1667 68 : rtx_insn *new_label = BB_HEAD (jump_block);
1668 :
1669 68 : if (JUMP_LABEL (insn) == old_label)
1670 : {
1671 55 : JUMP_LABEL (insn) = new_label;
1672 55 : note = find_reg_note (insn, REG_LABEL_TARGET, new_label);
1673 55 : if (note)
1674 0 : remove_note (insn, note);
1675 : }
1676 : else
1677 : {
1678 13 : note = find_reg_note (insn, REG_LABEL_TARGET, old_label);
1679 13 : if (note)
1680 13 : remove_note (insn, note);
1681 13 : if (JUMP_LABEL (insn) != new_label
1682 13 : && !find_reg_note (insn, REG_LABEL_TARGET, new_label))
1683 13 : add_reg_note (insn, REG_LABEL_TARGET, new_label);
1684 : }
1685 136 : while ((note = find_reg_note (insn, REG_LABEL_OPERAND, old_label))
1686 68 : != NULL_RTX)
1687 0 : XEXP (note, 0) = new_label;
1688 : }
1689 :
1690 993122 : new_bb = jump_block;
1691 : }
1692 : else
1693 : jump_block = e->src;
1694 :
1695 5282879 : const location_t loc = e->goto_locus;
1696 5282879 : e->flags &= ~EDGE_FALLTHRU;
1697 5282879 : if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
1698 : {
1699 736 : if (jump_label == ret_rtx)
1700 0 : emit_jump_insn_after_setloc (targetm.gen_return (),
1701 0 : BB_END (jump_block), loc);
1702 : else
1703 : {
1704 736 : gcc_assert (jump_label == simple_return_rtx);
1705 736 : emit_jump_insn_after_setloc (targetm.gen_simple_return (),
1706 736 : BB_END (jump_block), loc);
1707 : }
1708 736 : set_return_jump_label (BB_END (jump_block));
1709 : }
1710 : else
1711 : {
1712 5282143 : rtx_code_label *label = block_label (target);
1713 5282143 : emit_jump_insn_after_setloc (targetm.gen_jump (label),
1714 5282143 : BB_END (jump_block), loc);
1715 5282143 : JUMP_LABEL (BB_END (jump_block)) = label;
1716 5282143 : LABEL_NUSES (label)++;
1717 : }
1718 :
1719 : /* We might be in cfg layout mode, and if so, the following routine will
1720 : insert the barrier correctly. */
1721 5282879 : emit_barrier_after_bb (jump_block);
1722 5282879 : redirect_edge_succ_nodup (e, target);
1723 :
1724 5282879 : if (abnormal_edge_flags)
1725 0 : make_edge (src, target, abnormal_edge_flags);
1726 :
1727 5282879 : df_mark_solutions_dirty ();
1728 5282879 : fixup_partition_crossing (e);
1729 5282879 : return new_bb;
1730 : }
1731 :
1732 : /* Edge E is assumed to be fallthru edge. Emit needed jump instruction
1733 : (and possibly create new basic block) to make edge non-fallthru.
1734 : Return newly created BB or NULL if none. */
1735 :
1736 : static basic_block
1737 780346 : rtl_force_nonfallthru (edge e)
1738 : {
1739 780346 : return force_nonfallthru_and_redirect (e, e->dest, NULL_RTX);
1740 : }
1741 :
1742 : /* Redirect edge even at the expense of creating new jump insn or
1743 : basic block. Return new basic block if created, NULL otherwise.
1744 : Conversion must be possible. */
1745 :
1746 : static basic_block
1747 491971 : rtl_redirect_edge_and_branch_force (edge e, basic_block target)
1748 : {
1749 491971 : if (redirect_edge_and_branch (e, target)
1750 491971 : || e->dest == target)
1751 : return NULL;
1752 :
1753 : /* In case the edge redirection failed, try to force it to be non-fallthru
1754 : and redirect newly created simplejump. */
1755 399904 : df_set_bb_dirty (e->src);
1756 399904 : return force_nonfallthru_and_redirect (e, target, NULL_RTX);
1757 : }
1758 :
1759 : /* The given edge should potentially be a fallthru edge. If that is in
1760 : fact true, delete the jump and barriers that are in the way. */
1761 :
1762 : static void
1763 812104 : rtl_tidy_fallthru_edge (edge e)
1764 : {
1765 812104 : rtx_insn *q;
1766 812104 : basic_block b = e->src, c = b->next_bb;
1767 :
1768 : /* ??? In a late-running flow pass, other folks may have deleted basic
1769 : blocks by nopping out blocks, leaving multiple BARRIERs between here
1770 : and the target label. They ought to be chastised and fixed.
1771 :
1772 : We can also wind up with a sequence of undeletable labels between
1773 : one block and the next.
1774 :
1775 : So search through a sequence of barriers, labels, and notes for
1776 : the head of block C and assert that we really do fall through. */
1777 :
1778 1651428 : for (q = NEXT_INSN (BB_END (b)); q != BB_HEAD (c); q = NEXT_INSN (q))
1779 27220 : if (NONDEBUG_INSN_P (q))
1780 : return;
1781 :
1782 : /* Remove what will soon cease being the jump insn from the source block.
1783 : If block B consisted only of this single jump, turn it into a deleted
1784 : note. */
1785 812104 : q = BB_END (b);
1786 812104 : if (JUMP_P (q)
1787 33787 : && onlyjump_p (q)
1788 845879 : && (any_uncondjump_p (q)
1789 7420 : || single_succ_p (b)))
1790 : {
1791 26696 : rtx_insn *label;
1792 26696 : rtx_jump_table_data *table;
1793 :
1794 26696 : if (tablejump_p (q, &label, &table))
1795 : {
1796 : /* The label is likely mentioned in some instruction before
1797 : the tablejump and might not be DCEd, so turn it into
1798 : a note instead and move before the tablejump that is going to
1799 : be deleted. */
1800 0 : const char *name = LABEL_NAME (label);
1801 0 : PUT_CODE (label, NOTE);
1802 0 : NOTE_KIND (label) = NOTE_INSN_DELETED_LABEL;
1803 0 : NOTE_DELETED_LABEL_NAME (label) = name;
1804 0 : reorder_insns (label, label, PREV_INSN (q));
1805 0 : delete_insn (table);
1806 : }
1807 :
1808 26696 : q = PREV_INSN (q);
1809 : }
1810 : /* Unconditional jumps with side-effects (i.e. which we can't just delete
1811 : together with the barrier) should never have a fallthru edge. */
1812 785408 : else if (JUMP_P (q) && any_uncondjump_p (q))
1813 : return;
1814 :
1815 : /* Selectively unlink the sequence. */
1816 812104 : if (q != PREV_INSN (BB_HEAD (c)))
1817 27025 : delete_insn_chain (NEXT_INSN (q), PREV_INSN (BB_HEAD (c)), false);
1818 :
1819 812104 : e->flags |= EDGE_FALLTHRU;
1820 : }
1821 :
1822 : /* Should move basic block BB after basic block AFTER. NIY. */
1823 :
1824 : static bool
1825 679754 : rtl_move_block_after (basic_block bb ATTRIBUTE_UNUSED,
1826 : basic_block after ATTRIBUTE_UNUSED)
1827 : {
1828 679754 : return false;
1829 : }
1830 :
1831 : /* Locate the last bb in the same partition as START_BB. */
1832 :
1833 : static basic_block
1834 34165 : last_bb_in_partition (basic_block start_bb)
1835 : {
1836 34165 : basic_block bb;
1837 22390829 : FOR_BB_BETWEEN (bb, start_bb, EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
1838 : {
1839 22390829 : if (BB_PARTITION (start_bb) != BB_PARTITION (bb->next_bb))
1840 : return bb;
1841 : }
1842 : /* Return bb before the exit block. */
1843 0 : return bb->prev_bb;
1844 : }
1845 :
1846 : /* Split a (typically critical) edge. Return the new block.
1847 : The edge must not be abnormal.
1848 :
1849 : ??? The code generally expects to be called on critical edges.
1850 : The case of a block ending in an unconditional jump to a
1851 : block with multiple predecessors is not handled optimally. */
1852 :
1853 : static basic_block
1854 1207273 : rtl_split_edge (edge edge_in)
1855 : {
1856 1207273 : basic_block bb, new_bb;
1857 1207273 : rtx_insn *before;
1858 :
1859 : /* Abnormal edges cannot be split. */
1860 1207273 : gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
1861 :
1862 : /* We are going to place the new block in front of edge destination.
1863 : Avoid existence of fallthru predecessors. */
1864 1207273 : if ((edge_in->flags & EDGE_FALLTHRU) == 0)
1865 : {
1866 697495 : edge e = find_fallthru_edge (edge_in->dest->preds);
1867 :
1868 697495 : if (e)
1869 534307 : force_nonfallthru (e);
1870 : }
1871 :
1872 : /* Create the basic block note. */
1873 1207273 : if (edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
1874 969669 : before = BB_HEAD (edge_in->dest);
1875 : else
1876 : before = NULL;
1877 :
1878 : /* If this is a fall through edge to the exit block, the blocks might be
1879 : not adjacent, and the right place is after the source. */
1880 1207273 : if ((edge_in->flags & EDGE_FALLTHRU)
1881 509778 : && edge_in->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
1882 : {
1883 237604 : before = NEXT_INSN (BB_END (edge_in->src));
1884 237604 : bb = create_basic_block (before, NULL, edge_in->src);
1885 237604 : BB_COPY_PARTITION (bb, edge_in->src);
1886 237604 : }
1887 : else
1888 : {
1889 969669 : if (edge_in->src == ENTRY_BLOCK_PTR_FOR_FN (cfun))
1890 : {
1891 77189 : bb = create_basic_block (before, NULL, edge_in->dest->prev_bb);
1892 77189 : BB_COPY_PARTITION (bb, edge_in->dest);
1893 : }
1894 : else
1895 : {
1896 892480 : basic_block after = edge_in->dest->prev_bb;
1897 : /* If this is post-bb reordering, and the edge crosses a partition
1898 : boundary, the new block needs to be inserted in the bb chain
1899 : at the end of the src partition (since we put the new bb into
1900 : that partition, see below). Otherwise we may end up creating
1901 : an extra partition crossing in the chain, which is illegal.
1902 : It can't go after the src, because src may have a fall-through
1903 : to a different block. */
1904 892480 : if (crtl->bb_reorder_complete
1905 62964 : && (edge_in->flags & EDGE_CROSSING))
1906 : {
1907 34165 : after = last_bb_in_partition (edge_in->src);
1908 34165 : before = get_last_bb_insn (after);
1909 : /* The instruction following the last bb in partition should
1910 : be a barrier, since it cannot end in a fall-through. */
1911 34165 : gcc_checking_assert (BARRIER_P (before));
1912 34165 : before = NEXT_INSN (before);
1913 : }
1914 892480 : bb = create_basic_block (before, NULL, after);
1915 : /* Put the split bb into the src partition, to avoid creating
1916 : a situation where a cold bb dominates a hot bb, in the case
1917 : where src is cold and dest is hot. The src will dominate
1918 : the new bb (whereas it might not have dominated dest). */
1919 892480 : BB_COPY_PARTITION (bb, edge_in->src);
1920 : }
1921 : }
1922 :
1923 1207273 : make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU);
1924 :
1925 : /* Can't allow a region crossing edge to be fallthrough. */
1926 1207273 : if (BB_PARTITION (bb) != BB_PARTITION (edge_in->dest)
1927 71655 : && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
1928 : {
1929 41204 : new_bb = force_nonfallthru (single_succ_edge (bb));
1930 41204 : gcc_assert (!new_bb);
1931 : }
1932 :
1933 : /* For non-fallthru edges, we must adjust the predecessor's
1934 : jump instruction to target our new block. */
1935 1207273 : if ((edge_in->flags & EDGE_FALLTHRU) == 0)
1936 : {
1937 697495 : edge redirected = redirect_edge_and_branch (edge_in, bb);
1938 697495 : gcc_assert (redirected);
1939 : }
1940 : else
1941 : {
1942 509778 : if (edge_in->src != ENTRY_BLOCK_PTR_FOR_FN (cfun))
1943 : {
1944 : /* For asm goto even splitting of fallthru edge might
1945 : need insn patching, as other labels might point to the
1946 : old label. */
1947 432589 : rtx_insn *last = BB_END (edge_in->src);
1948 432589 : if (last
1949 432589 : && JUMP_P (last)
1950 209164 : && edge_in->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
1951 185228 : && (extract_asm_operands (PATTERN (last))
1952 185226 : || JUMP_LABEL (last) == before)
1953 432591 : && patch_jump_insn (last, before, bb))
1954 2 : df_set_bb_dirty (edge_in->src);
1955 : }
1956 509778 : redirect_edge_succ (edge_in, bb);
1957 : }
1958 :
1959 1207273 : return bb;
1960 : }
1961 :
1962 : /* Queue instructions for insertion on an edge between two basic blocks.
1963 : The new instructions and basic blocks (if any) will not appear in the
1964 : CFG until commit_edge_insertions is called. If there are already
1965 : queued instructions on the edge, PATTERN is appended to them. */
1966 :
1967 : void
1968 5734096 : insert_insn_on_edge (rtx pattern, edge e)
1969 : {
1970 : /* We cannot insert instructions on an abnormal critical edge.
1971 : It will be easier to find the culprit if we die now. */
1972 5734096 : gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e)));
1973 :
1974 5734096 : if (e->insns.r == NULL_RTX)
1975 4813130 : start_sequence ();
1976 : else
1977 920966 : push_to_sequence (e->insns.r);
1978 :
1979 5734096 : emit_insn (pattern);
1980 :
1981 5734096 : e->insns.r = end_sequence ();
1982 5734096 : }
1983 :
1984 : /* Like insert_insn_on_edge, but if there are already queued instructions
1985 : on the edge, PATTERN is prepended to them. */
1986 :
1987 : void
1988 335 : prepend_insn_to_edge (rtx pattern, edge e)
1989 : {
1990 : /* We cannot insert instructions on an abnormal critical edge.
1991 : It will be easier to find the culprit if we die now. */
1992 335 : gcc_assert (!((e->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (e)));
1993 :
1994 335 : start_sequence ();
1995 :
1996 335 : emit_insn (pattern);
1997 335 : emit_insn (e->insns.r);
1998 :
1999 335 : e->insns.r = end_sequence ();
2000 335 : }
2001 :
2002 : /* Update the CFG for the instructions queued on edge E. */
2003 :
2004 : void
2005 4777992 : commit_one_edge_insertion (edge e)
2006 : {
2007 4777992 : rtx_insn *before = NULL, *after = NULL, *insns, *tmp, *last;
2008 4777992 : basic_block bb;
2009 :
2010 : /* Pull the insns off the edge now since the edge might go away. */
2011 4777992 : insns = e->insns.r;
2012 4777992 : e->insns.r = NULL;
2013 :
2014 : /* Allow the sequence to contain internal jumps, such as a memcpy loop
2015 : or an allocation loop. If such a sequence is emitted during RTL
2016 : expansion, we'll create the appropriate basic blocks later,
2017 : at the end of the pass. But if such a sequence is emitted after
2018 : initial expansion, we'll need to find the subblocks ourselves. */
2019 4777992 : bool contains_jump = false;
2020 4777992 : if (!currently_expanding_to_rtl)
2021 13509207 : for (rtx_insn *insn = insns; insn; insn = NEXT_INSN (insn))
2022 11574967 : if (JUMP_P (insn))
2023 : {
2024 1602052 : rebuild_jump_labels_chain (insns);
2025 1602052 : contains_jump = true;
2026 1602052 : break;
2027 : }
2028 :
2029 : /* Figure out where to put these insns. If the destination has
2030 : one predecessor, insert there. Except for the exit block. */
2031 4777992 : if (single_pred_p (e->dest) && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
2032 : {
2033 1602659 : bb = e->dest;
2034 :
2035 : /* Get the location correct wrt a code label, and "nice" wrt
2036 : a basic block note, and before everything else. */
2037 1602659 : tmp = BB_HEAD (bb);
2038 1602659 : if (LABEL_P (tmp))
2039 77407 : tmp = NEXT_INSN (tmp);
2040 1602659 : if (NOTE_INSN_BASIC_BLOCK_P (tmp))
2041 1602659 : tmp = NEXT_INSN (tmp);
2042 1602659 : if (tmp == BB_HEAD (bb))
2043 : before = tmp;
2044 1602659 : else if (tmp)
2045 1602659 : after = PREV_INSN (tmp);
2046 : else
2047 0 : after = get_last_insn ();
2048 : }
2049 :
2050 : /* If the source has one successor and the edge is not abnormal,
2051 : insert there. Except for the entry block.
2052 : Don't do this if the predecessor ends in a jump other than
2053 : unconditional simple jump. E.g. for asm goto that points all
2054 : its labels at the fallthru basic block, we can't insert instructions
2055 : before the asm goto, as the asm goto can have various of side effects,
2056 : and can't emit instructions after the asm goto, as it must end
2057 : the basic block. */
2058 3175333 : else if ((e->flags & EDGE_ABNORMAL) == 0
2059 3175333 : && single_succ_p (e->src)
2060 2250816 : && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
2061 5424667 : && (!JUMP_P (BB_END (e->src))
2062 369589 : || simplejump_p (BB_END (e->src))))
2063 : {
2064 2249334 : bb = e->src;
2065 :
2066 : /* It is possible to have a non-simple jump here. Consider a target
2067 : where some forms of unconditional jumps clobber a register. This
2068 : happens on the fr30 for example.
2069 :
2070 : We know this block has a single successor, so we can just emit
2071 : the queued insns before the jump. */
2072 2249334 : if (JUMP_P (BB_END (bb)))
2073 : before = BB_END (bb);
2074 : else
2075 : {
2076 : /* We'd better be fallthru, or we've lost track of what's what. */
2077 1879745 : gcc_assert (e->flags & EDGE_FALLTHRU);
2078 :
2079 : after = BB_END (bb);
2080 : }
2081 : }
2082 :
2083 : /* Otherwise we must split the edge. */
2084 : else
2085 : {
2086 925999 : bb = split_edge (e);
2087 :
2088 : /* If E crossed a partition boundary, we needed to make bb end in
2089 : a region-crossing jump, even though it was originally fallthru. */
2090 925999 : if (JUMP_P (BB_END (bb)))
2091 : before = BB_END (bb);
2092 : else
2093 : after = BB_END (bb);
2094 : }
2095 :
2096 : /* Now that we've found the spot, do the insertion. */
2097 1602659 : if (before)
2098 : {
2099 410792 : emit_insn_before_noloc (insns, before, bb);
2100 410792 : last = prev_nonnote_insn (before);
2101 : }
2102 : else
2103 4367200 : last = emit_insn_after_noloc (insns, after, bb);
2104 :
2105 4777992 : if (returnjump_p (last))
2106 : {
2107 : /* ??? Remove all outgoing edges from BB and add one for EXIT.
2108 : This is not currently a problem because this only happens
2109 : for the (single) epilogue, which already has a fallthru edge
2110 : to EXIT. */
2111 :
2112 1342124 : e = single_succ_edge (bb);
2113 2684248 : gcc_assert (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
2114 : && single_succ_p (bb) && (e->flags & EDGE_FALLTHRU));
2115 :
2116 1342124 : e->flags &= ~EDGE_FALLTHRU;
2117 1342124 : emit_barrier_after (last);
2118 :
2119 1342124 : if (before)
2120 0 : delete_insn (before);
2121 : }
2122 : else
2123 : /* Sequences inserted after RTL expansion are expected to be SESE,
2124 : with only internal branches allowed. If the sequence jumps outside
2125 : itself then we do not know how to add the associated edges here. */
2126 3435868 : gcc_assert (!JUMP_P (last) || currently_expanding_to_rtl);
2127 :
2128 4777992 : if (contains_jump)
2129 1602052 : find_sub_basic_blocks (bb);
2130 4777992 : }
2131 :
2132 : /* Update the CFG for all queued instructions. */
2133 :
2134 : void
2135 4533608 : commit_edge_insertions (void)
2136 : {
2137 4533608 : basic_block bb;
2138 :
2139 : /* Optimization passes that invoke this routine can cause hot blocks
2140 : previously reached by both hot and cold blocks to become dominated only
2141 : by cold blocks. This will cause the verification below to fail,
2142 : and lead to now cold code in the hot section. In some cases this
2143 : may only be visible after newly unreachable blocks are deleted,
2144 : which will be done by fixup_partitions. */
2145 4533608 : fixup_partitions ();
2146 :
2147 4533608 : if (!currently_expanding_to_rtl)
2148 3061468 : checking_verify_flow_info ();
2149 :
2150 67095964 : FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR_FOR_FN (cfun),
2151 : EXIT_BLOCK_PTR_FOR_FN (cfun), next_bb)
2152 : {
2153 62562356 : edge e;
2154 62562356 : edge_iterator ei;
2155 :
2156 149628264 : FOR_EACH_EDGE (e, ei, bb->succs)
2157 87065908 : if (e->insns.r)
2158 : {
2159 4737762 : if (currently_expanding_to_rtl)
2160 1241700 : rebuild_jump_labels_chain (e->insns.r);
2161 4737762 : commit_one_edge_insertion (e);
2162 : }
2163 : }
2164 4533608 : }
2165 :
2166 :
2167 : /* Print out RTL-specific basic block information (live information
2168 : at start and end with TDF_DETAILS). FLAGS are the TDF_* masks
2169 : documented in dumpfile.h. */
2170 :
2171 : static void
2172 2713 : rtl_dump_bb (FILE *outf, basic_block bb, int indent, dump_flags_t flags)
2173 : {
2174 2713 : char *s_indent;
2175 :
2176 2713 : s_indent = (char *) alloca ((size_t) indent + 1);
2177 2713 : memset (s_indent, ' ', (size_t) indent);
2178 2713 : s_indent[indent] = '\0';
2179 :
2180 2713 : if (df && (flags & TDF_DETAILS))
2181 : {
2182 728 : df_dump_top (bb, outf);
2183 728 : putc ('\n', outf);
2184 : }
2185 :
2186 2713 : if (bb->index != ENTRY_BLOCK && bb->index != EXIT_BLOCK
2187 2713 : && rtl_bb_info_initialized_p (bb))
2188 : {
2189 2137 : rtx_insn *last = BB_END (bb);
2190 2137 : if (last)
2191 2137 : last = NEXT_INSN (last);
2192 15607 : for (rtx_insn *insn = BB_HEAD (bb); insn != last; insn = NEXT_INSN (insn))
2193 : {
2194 13470 : if (flags & TDF_DETAILS)
2195 4176 : df_dump_insn_top (insn, outf);
2196 13470 : if (! (flags & TDF_SLIM))
2197 13438 : print_rtl_single (outf, insn);
2198 : else
2199 32 : dump_insn_slim (outf, insn);
2200 13470 : if (flags & TDF_DETAILS)
2201 4176 : df_dump_insn_bottom (insn, outf);
2202 : }
2203 : }
2204 :
2205 2713 : if (df && (flags & TDF_DETAILS))
2206 : {
2207 728 : df_dump_bottom (bb, outf);
2208 728 : putc ('\n', outf);
2209 : }
2210 :
2211 2713 : }
2212 :
2213 : /* Like dump_function_to_file, but for RTL. Print out dataflow information
2214 : for the start of each basic block. FLAGS are the TDF_* masks documented
2215 : in dumpfile.h. */
2216 :
2217 : void
2218 4219 : print_rtl_with_bb (FILE *outf, const rtx_insn *rtx_first, dump_flags_t flags)
2219 : {
2220 4219 : const rtx_insn *tmp_rtx;
2221 4219 : if (rtx_first == 0)
2222 0 : fprintf (outf, "(nil)\n");
2223 : else
2224 : {
2225 4219 : enum bb_state { NOT_IN_BB, IN_ONE_BB, IN_MULTIPLE_BB };
2226 4219 : int max_uid = get_max_uid ();
2227 4219 : basic_block *start = XCNEWVEC (basic_block, max_uid);
2228 4219 : basic_block *end = XCNEWVEC (basic_block, max_uid);
2229 4219 : enum bb_state *in_bb_p = XCNEWVEC (enum bb_state, max_uid);
2230 4219 : basic_block bb;
2231 :
2232 : /* After freeing the CFG, we still have BLOCK_FOR_INSN set on most
2233 : insns, but the CFG is not maintained so the basic block info
2234 : is not reliable. Therefore it's omitted from the dumps. */
2235 4219 : if (! (cfun->curr_properties & PROP_cfg))
2236 986 : flags &= ~TDF_BLOCKS;
2237 :
2238 4219 : if (df)
2239 3319 : df_dump_start (outf);
2240 :
2241 4219 : if (cfun->curr_properties & PROP_cfg)
2242 : {
2243 21752 : FOR_EACH_BB_REVERSE_FN (bb, cfun)
2244 : {
2245 18519 : rtx_insn *x;
2246 :
2247 18519 : start[INSN_UID (BB_HEAD (bb))] = bb;
2248 18519 : end[INSN_UID (BB_END (bb))] = bb;
2249 18519 : if (flags & TDF_BLOCKS)
2250 : {
2251 5331 : for (x = BB_HEAD (bb); x != NULL_RTX; x = NEXT_INSN (x))
2252 : {
2253 5331 : enum bb_state state = IN_MULTIPLE_BB;
2254 :
2255 5331 : if (in_bb_p[INSN_UID (x)] == NOT_IN_BB)
2256 5331 : state = IN_ONE_BB;
2257 5331 : in_bb_p[INSN_UID (x)] = state;
2258 :
2259 5331 : if (x == BB_END (bb))
2260 : break;
2261 : }
2262 : }
2263 : }
2264 : }
2265 :
2266 164513 : for (tmp_rtx = rtx_first; tmp_rtx != NULL; tmp_rtx = NEXT_INSN (tmp_rtx))
2267 : {
2268 160294 : if (flags & TDF_BLOCKS)
2269 : {
2270 6127 : bb = start[INSN_UID (tmp_rtx)];
2271 6127 : if (bb != NULL)
2272 : {
2273 885 : dump_bb_info (outf, bb, 0, dump_flags, true, false);
2274 885 : if (df && (flags & TDF_DETAILS))
2275 582 : df_dump_top (bb, outf);
2276 : }
2277 :
2278 6127 : if (in_bb_p[INSN_UID (tmp_rtx)] == NOT_IN_BB
2279 796 : && !NOTE_P (tmp_rtx)
2280 6341 : && !BARRIER_P (tmp_rtx))
2281 0 : fprintf (outf, ";; Insn is not within a basic block\n");
2282 6127 : else if (in_bb_p[INSN_UID (tmp_rtx)] == IN_MULTIPLE_BB)
2283 0 : fprintf (outf, ";; Insn is in multiple basic blocks\n");
2284 : }
2285 :
2286 160294 : if (flags & TDF_DETAILS)
2287 17653 : df_dump_insn_top (tmp_rtx, outf);
2288 160294 : if (! (flags & TDF_SLIM))
2289 159758 : print_rtl_single (outf, tmp_rtx);
2290 : else
2291 536 : dump_insn_slim (outf, tmp_rtx);
2292 160294 : if (flags & TDF_DETAILS)
2293 17653 : df_dump_insn_bottom (tmp_rtx, outf);
2294 :
2295 160294 : bb = end[INSN_UID (tmp_rtx)];
2296 160294 : if (bb != NULL)
2297 : {
2298 18519 : if (flags & TDF_BLOCKS)
2299 : {
2300 885 : dump_bb_info (outf, bb, 0, dump_flags, false, true);
2301 885 : if (df && (flags & TDF_DETAILS))
2302 582 : df_dump_bottom (bb, outf);
2303 885 : putc ('\n', outf);
2304 : }
2305 : /* Emit a hint if the fallthrough target of current basic block
2306 : isn't the one placed right next. */
2307 177875 : else if (EDGE_COUNT (bb->succs) > 0)
2308 : {
2309 17581 : gcc_assert (BB_END (bb) == tmp_rtx);
2310 17581 : const rtx_insn *ninsn = NEXT_INSN (tmp_rtx);
2311 : /* Bypass intervening deleted-insn notes and debug insns. */
2312 17581 : while (ninsn
2313 18865 : && !NONDEBUG_INSN_P (ninsn)
2314 40450 : && !start[INSN_UID (ninsn)])
2315 4004 : ninsn = NEXT_INSN (ninsn);
2316 17581 : edge e = find_fallthru_edge (bb->succs);
2317 17581 : if (e && ninsn)
2318 : {
2319 12847 : basic_block dest = e->dest;
2320 12847 : if (start[INSN_UID (ninsn)] != dest)
2321 2159 : fprintf (outf, "%s ; pc falls through to BB %d\n",
2322 : print_rtx_head, dest->index);
2323 : }
2324 : }
2325 : }
2326 : }
2327 :
2328 4219 : free (start);
2329 4219 : free (end);
2330 4219 : free (in_bb_p);
2331 : }
2332 4219 : }
2333 :
2334 : /* Update the branch probability of BB if a REG_BR_PROB is present. */
2335 :
2336 : void
2337 9719599 : update_br_prob_note (basic_block bb)
2338 : {
2339 9719599 : rtx note;
2340 9719599 : note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX);
2341 9719599 : if (!JUMP_P (BB_END (bb)) || !BRANCH_EDGE (bb)->probability.initialized_p ())
2342 : {
2343 248627 : if (note)
2344 : {
2345 3 : rtx *note_link, this_rtx;
2346 :
2347 3 : note_link = ®_NOTES (BB_END (bb));
2348 6 : for (this_rtx = *note_link; this_rtx; this_rtx = XEXP (this_rtx, 1))
2349 6 : if (this_rtx == note)
2350 : {
2351 3 : *note_link = XEXP (this_rtx, 1);
2352 3 : break;
2353 : }
2354 : }
2355 248627 : return;
2356 : }
2357 9470972 : if (!note
2358 9470972 : || XINT (note, 0) == BRANCH_EDGE (bb)->probability.to_reg_br_prob_note ())
2359 : return;
2360 203583 : XINT (note, 0) = BRANCH_EDGE (bb)->probability.to_reg_br_prob_note ();
2361 : }
2362 :
2363 : /* Get the last insn associated with block BB (that includes barriers and
2364 : tablejumps after BB). */
2365 : rtx_insn *
2366 6767453 : get_last_bb_insn (basic_block bb)
2367 : {
2368 6767453 : rtx_jump_table_data *table;
2369 6767453 : rtx_insn *tmp;
2370 6767453 : rtx_insn *end = BB_END (bb);
2371 :
2372 : /* Include any jump table following the basic block. */
2373 6767453 : if (tablejump_p (end, NULL, &table))
2374 5 : end = table;
2375 :
2376 : /* Include any barriers that may follow the basic block. */
2377 6767453 : tmp = next_nonnote_nondebug_insn_bb (end);
2378 14131880 : while (tmp && BARRIER_P (tmp))
2379 : {
2380 596974 : end = tmp;
2381 596974 : tmp = next_nonnote_nondebug_insn_bb (end);
2382 : }
2383 :
2384 6767453 : return end;
2385 : }
2386 :
2387 : /* Add all BBs reachable from entry via hot paths into the SET. */
2388 :
2389 : void
2390 563178 : find_bbs_reachable_by_hot_paths (hash_set<basic_block> *set)
2391 : {
2392 563178 : auto_vec<basic_block, 64> worklist;
2393 :
2394 563178 : set->add (ENTRY_BLOCK_PTR_FOR_FN (cfun));
2395 563178 : worklist.safe_push (ENTRY_BLOCK_PTR_FOR_FN (cfun));
2396 :
2397 20474734 : while (worklist.length () > 0)
2398 : {
2399 19348378 : basic_block bb = worklist.pop ();
2400 19348378 : edge_iterator ei;
2401 19348378 : edge e;
2402 :
2403 49202193 : FOR_EACH_EDGE (e, ei, bb->succs)
2404 29853815 : if (BB_PARTITION (e->dest) != BB_COLD_PARTITION
2405 29853815 : && !set->add (e->dest))
2406 18785200 : worklist.safe_push (e->dest);
2407 : }
2408 563178 : }
2409 :
2410 : /* Sanity check partition hotness to ensure that basic blocks in
2411 : Â the cold partition don't dominate basic blocks in the hot partition.
2412 : If FLAG_ONLY is true, report violations as errors. Otherwise
2413 : re-mark the dominated blocks as cold, since this is run after
2414 : cfg optimizations that may make hot blocks previously reached
2415 : by both hot and cold blocks now only reachable along cold paths. */
2416 :
2417 : static auto_vec<basic_block>
2418 498467 : find_partition_fixes (bool flag_only)
2419 : {
2420 498467 : basic_block bb;
2421 498467 : auto_vec<basic_block> bbs_to_fix;
2422 498467 : hash_set<basic_block> set;
2423 :
2424 : /* Callers check this. */
2425 498467 : gcc_checking_assert (crtl->has_bb_partition);
2426 :
2427 498467 : find_bbs_reachable_by_hot_paths (&set);
2428 :
2429 19220627 : FOR_EACH_BB_FN (bb, cfun)
2430 18722160 : if (!set.contains (bb)
2431 18722160 : && BB_PARTITION (bb) != BB_COLD_PARTITION)
2432 : {
2433 320 : if (flag_only)
2434 0 : error ("non-cold basic block %d reachable only "
2435 : "by paths crossing the cold partition", bb->index);
2436 : else
2437 320 : BB_SET_PARTITION (bb, BB_COLD_PARTITION);
2438 320 : bbs_to_fix.safe_push (bb);
2439 : }
2440 :
2441 498467 : return bbs_to_fix;
2442 498467 : }
2443 :
2444 : /* Perform cleanup on the hot/cold bb partitioning after optimization
2445 : passes that modify the cfg. */
2446 :
2447 : void
2448 12816073 : fixup_partitions (void)
2449 : {
2450 12816073 : if (!crtl->has_bb_partition)
2451 12440979 : return;
2452 :
2453 : /* Delete any blocks that became unreachable and weren't
2454 : already cleaned up, for example during edge forwarding
2455 : and convert_jumps_to_returns. This will expose more
2456 : opportunities for fixing the partition boundaries here.
2457 : Also, the calculation of the dominance graph during verification
2458 : will assert if there are unreachable nodes. */
2459 375094 : delete_unreachable_blocks ();
2460 :
2461 : /* If there are partitions, do a sanity check on them: A basic block in
2462 : Â a cold partition cannot dominate a basic block in a hot partition.
2463 : Fixup any that now violate this requirement, as a result of edge
2464 : forwarding and unreachable block deletion. Â */
2465 375094 : auto_vec<basic_block> bbs_to_fix = find_partition_fixes (false);
2466 :
2467 : /* Do the partition fixup after all necessary blocks have been converted to
2468 : cold, so that we only update the region crossings the minimum number of
2469 : places, which can require forcing edges to be non fallthru. */
2470 375375 : if (! bbs_to_fix.is_empty ())
2471 : {
2472 320 : do
2473 : {
2474 320 : basic_block bb = bbs_to_fix.pop ();
2475 320 : fixup_new_cold_bb (bb);
2476 : }
2477 601 : while (! bbs_to_fix.is_empty ());
2478 :
2479 : /* Fix up hot cold block grouping if needed. */
2480 281 : if (crtl->bb_reorder_complete && current_ir_type () == IR_RTL_CFGRTL)
2481 : {
2482 1 : basic_block bb, first = NULL, second = NULL;
2483 1 : int current_partition = BB_UNPARTITIONED;
2484 :
2485 16 : FOR_EACH_BB_FN (bb, cfun)
2486 : {
2487 15 : if (current_partition != BB_UNPARTITIONED
2488 14 : && BB_PARTITION (bb) != current_partition)
2489 : {
2490 3 : if (first == NULL)
2491 : first = bb;
2492 2 : else if (second == NULL)
2493 : second = bb;
2494 : else
2495 : {
2496 : /* If we switch partitions for the 3rd, 5th etc. time,
2497 : move bbs first (inclusive) .. second (exclusive) right
2498 : before bb. */
2499 1 : basic_block prev_first = first->prev_bb;
2500 1 : basic_block prev_second = second->prev_bb;
2501 1 : basic_block prev_bb = bb->prev_bb;
2502 1 : prev_first->next_bb = second;
2503 1 : second->prev_bb = prev_first;
2504 1 : prev_second->next_bb = bb;
2505 1 : bb->prev_bb = prev_second;
2506 1 : prev_bb->next_bb = first;
2507 1 : first->prev_bb = prev_bb;
2508 1 : rtx_insn *prev_first_insn = PREV_INSN (BB_HEAD (first));
2509 1 : rtx_insn *prev_second_insn
2510 1 : = PREV_INSN (BB_HEAD (second));
2511 1 : rtx_insn *prev_bb_insn = PREV_INSN (BB_HEAD (bb));
2512 1 : SET_NEXT_INSN (prev_first_insn) = BB_HEAD (second);
2513 1 : SET_PREV_INSN (BB_HEAD (second)) = prev_first_insn;
2514 1 : SET_NEXT_INSN (prev_second_insn) = BB_HEAD (bb);
2515 1 : SET_PREV_INSN (BB_HEAD (bb)) = prev_second_insn;
2516 1 : SET_NEXT_INSN (prev_bb_insn) = BB_HEAD (first);
2517 1 : SET_PREV_INSN (BB_HEAD (first)) = prev_bb_insn;
2518 1 : second = NULL;
2519 : }
2520 : }
2521 15 : current_partition = BB_PARTITION (bb);
2522 : }
2523 1 : gcc_assert (!second);
2524 : }
2525 : }
2526 375094 : }
2527 :
2528 : /* Verify, in the basic block chain, that there is at most one switch
2529 : between hot/cold partitions. This condition will not be true until
2530 : after reorder_basic_blocks is called. */
2531 :
2532 : static bool
2533 62618957 : verify_hot_cold_block_grouping (void)
2534 : {
2535 62618957 : basic_block bb;
2536 62618957 : bool err = false;
2537 62618957 : bool switched_sections = false;
2538 62618957 : int current_partition = BB_UNPARTITIONED;
2539 :
2540 : /* Even after bb reordering is complete, we go into cfglayout mode
2541 : again (in compgoto). Ensure we don't call this before going back
2542 : into linearized RTL when any layout fixes would have been committed. */
2543 62618957 : if (!crtl->bb_reorder_complete
2544 62618957 : || current_ir_type () != IR_RTL_CFGRTL)
2545 55300621 : return err;
2546 :
2547 130106839 : FOR_EACH_BB_FN (bb, cfun)
2548 : {
2549 122788503 : if (current_partition != BB_UNPARTITIONED
2550 51093128 : && BB_PARTITION (bb) != current_partition)
2551 : {
2552 729734 : if (switched_sections)
2553 : {
2554 0 : error ("multiple hot/cold transitions found (bb %i)",
2555 : bb->index);
2556 0 : err = true;
2557 : }
2558 : else
2559 : switched_sections = true;
2560 :
2561 729734 : if (!crtl->has_bb_partition)
2562 0 : error ("partition found but function partition flag not set");
2563 : }
2564 122788503 : current_partition = BB_PARTITION (bb);
2565 : }
2566 :
2567 : return err;
2568 : }
2569 :
2570 :
2571 : /* Perform several checks on the edges out of each block, such as
2572 : the consistency of the branch probabilities, the correctness
2573 : of hot/cold partition crossing edges, and the number of expected
2574 : successor edges. Also verify that the dominance relationship
2575 : between hot/cold blocks is sane. */
2576 :
2577 : static bool
2578 98983531 : rtl_verify_edges (void)
2579 : {
2580 98983531 : bool err = false;
2581 98983531 : basic_block bb;
2582 :
2583 1179629870 : FOR_EACH_BB_REVERSE_FN (bb, cfun)
2584 : {
2585 1080646339 : int n_fallthru = 0, n_branch = 0, n_abnormal_call = 0, n_sibcall = 0;
2586 1080646339 : int n_eh = 0, n_abnormal = 0;
2587 1080646339 : edge e, fallthru = NULL;
2588 1080646339 : edge_iterator ei;
2589 1080646339 : rtx note;
2590 1080646339 : bool has_crossing_edge = false;
2591 :
2592 1080646339 : if (JUMP_P (BB_END (bb))
2593 637077752 : && (note = find_reg_note (BB_END (bb), REG_BR_PROB, NULL_RTX))
2594 439320004 : && EDGE_COUNT (bb->succs) >= 2
2595 1519966343 : && any_condjump_p (BB_END (bb)))
2596 : {
2597 439320004 : if (!BRANCH_EDGE (bb)->probability.initialized_p ())
2598 : {
2599 300952 : if (profile_status_for_fn (cfun) != PROFILE_ABSENT)
2600 : {
2601 0 : error ("verify_flow_info: "
2602 : "REG_BR_PROB is set but cfg probability is not");
2603 0 : err = true;
2604 : }
2605 : }
2606 439019052 : else if (XINT (note, 0)
2607 439019052 : != BRANCH_EDGE (bb)->probability.to_reg_br_prob_note ()
2608 439019052 : && profile_status_for_fn (cfun) != PROFILE_ABSENT)
2609 : {
2610 0 : error ("verify_flow_info: REG_BR_PROB does not match cfg %i %i",
2611 : XINT (note, 0),
2612 0 : BRANCH_EDGE (bb)->probability.to_reg_br_prob_note ());
2613 0 : err = true;
2614 : }
2615 : }
2616 :
2617 2656334884 : FOR_EACH_EDGE (e, ei, bb->succs)
2618 : {
2619 1575688545 : bool is_crossing;
2620 :
2621 1575688545 : if (e->flags & EDGE_FALLTHRU)
2622 860489679 : n_fallthru++, fallthru = e;
2623 :
2624 3151377090 : is_crossing = (BB_PARTITION (e->src) != BB_PARTITION (e->dest)
2625 36277355 : && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
2626 1611965900 : && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun));
2627 1575688545 : has_crossing_edge |= is_crossing;
2628 1575688545 : if (e->flags & EDGE_CROSSING)
2629 : {
2630 20460571 : if (!is_crossing)
2631 : {
2632 0 : error ("EDGE_CROSSING incorrectly set across same section");
2633 0 : err = true;
2634 : }
2635 20460571 : if (e->flags & EDGE_FALLTHRU)
2636 : {
2637 0 : error ("fallthru edge crosses section boundary in bb %i",
2638 0 : e->src->index);
2639 0 : err = true;
2640 : }
2641 20460571 : if (e->flags & EDGE_EH)
2642 : {
2643 0 : error ("EH edge crosses section boundary in bb %i",
2644 0 : e->src->index);
2645 0 : err = true;
2646 : }
2647 20460571 : if (JUMP_P (BB_END (bb)) && !CROSSING_JUMP_P (BB_END (bb)))
2648 : {
2649 0 : error ("No region crossing jump at section boundary in bb %i",
2650 : bb->index);
2651 0 : err = true;
2652 : }
2653 : }
2654 1555227974 : else if (is_crossing)
2655 : {
2656 0 : error ("EDGE_CROSSING missing across section boundary");
2657 0 : err = true;
2658 : }
2659 :
2660 1575688545 : if ((e->flags & ~(EDGE_DFS_BACK
2661 : | EDGE_CAN_FALLTHRU
2662 : | EDGE_IRREDUCIBLE_LOOP
2663 : | EDGE_LOOP_EXIT
2664 : | EDGE_CROSSING
2665 : | EDGE_PRESERVE)) == 0)
2666 643048480 : n_branch++;
2667 :
2668 1575688545 : if (e->flags & EDGE_ABNORMAL_CALL)
2669 50047800 : n_abnormal_call++;
2670 :
2671 1575688545 : if (e->flags & EDGE_SIBCALL)
2672 10731814 : n_sibcall++;
2673 :
2674 1575688545 : if (e->flags & EDGE_EH)
2675 59577419 : n_eh++;
2676 :
2677 1575688545 : if (e->flags & EDGE_ABNORMAL)
2678 71748681 : n_abnormal++;
2679 : }
2680 :
2681 1080646339 : if (!has_crossing_edge
2682 1060203326 : && JUMP_P (BB_END (bb))
2683 1697285466 : && CROSSING_JUMP_P (BB_END (bb)))
2684 : {
2685 0 : print_rtl_with_bb (stderr, get_insns (), TDF_BLOCKS | TDF_DETAILS);
2686 0 : error ("Region crossing jump across same section in bb %i",
2687 : bb->index);
2688 0 : err = true;
2689 : }
2690 :
2691 1080646339 : if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX))
2692 : {
2693 0 : error ("missing REG_EH_REGION note at the end of bb %i", bb->index);
2694 0 : err = true;
2695 : }
2696 1080646339 : if (n_eh > 1)
2697 : {
2698 0 : error ("too many exception handling edges in bb %i", bb->index);
2699 0 : err = true;
2700 : }
2701 1080646339 : if (n_branch
2702 1080646339 : && (!JUMP_P (BB_END (bb))
2703 636976810 : || (n_branch > 1 && (any_uncondjump_p (BB_END (bb))
2704 742057 : || any_condjump_p (BB_END (bb))))))
2705 : {
2706 0 : error ("too many outgoing branch edges from bb %i", bb->index);
2707 0 : err = true;
2708 : }
2709 1080646339 : if (n_fallthru && any_uncondjump_p (BB_END (bb)))
2710 : {
2711 0 : error ("fallthru edge after unconditional jump in bb %i", bb->index);
2712 0 : err = true;
2713 : }
2714 1080646339 : if (n_branch != 1 && any_uncondjump_p (BB_END (bb)))
2715 : {
2716 0 : error ("wrong number of branch edges after unconditional jump"
2717 : " in bb %i", bb->index);
2718 0 : err = true;
2719 : }
2720 444411586 : if (n_branch != 1 && any_condjump_p (BB_END (bb))
2721 1080647651 : && JUMP_LABEL (BB_END (bb)) != BB_HEAD (fallthru->dest))
2722 : {
2723 0 : error ("wrong amount of branch edges after conditional jump"
2724 : " in bb %i", bb->index);
2725 0 : err = true;
2726 : }
2727 1080646339 : if (n_abnormal_call && !CALL_P (BB_END (bb)))
2728 : {
2729 0 : error ("abnormal call edges for non-call insn in bb %i", bb->index);
2730 0 : err = true;
2731 : }
2732 1080646339 : if (n_sibcall && !CALL_P (BB_END (bb)))
2733 : {
2734 0 : error ("sibcall edges for non-call insn in bb %i", bb->index);
2735 0 : err = true;
2736 : }
2737 1080646339 : if (n_abnormal > n_eh
2738 10936632 : && !(CALL_P (BB_END (bb))
2739 10916507 : && n_abnormal == n_abnormal_call + n_sibcall)
2740 1080666464 : && (!JUMP_P (BB_END (bb))
2741 20125 : || any_condjump_p (BB_END (bb))
2742 20125 : || any_uncondjump_p (BB_END (bb))))
2743 : {
2744 0 : error ("abnormal edges for no purpose in bb %i", bb->index);
2745 0 : err = true;
2746 : }
2747 :
2748 1080646339 : int has_eh = -1;
2749 2649704704 : FOR_EACH_EDGE (e, ei, bb->preds)
2750 : {
2751 1569058365 : if (has_eh == -1)
2752 1080530668 : has_eh = (e->flags & EDGE_EH);
2753 1569058365 : if ((e->flags & EDGE_EH) == has_eh)
2754 1569058365 : continue;
2755 0 : error ("EH incoming edge mixed with non-EH incoming edges "
2756 : "in bb %i", bb->index);
2757 0 : err = true;
2758 0 : break;
2759 : }
2760 : }
2761 :
2762 : /* If there are partitions, do a sanity check on them: A basic block in
2763 : Â a cold partition cannot dominate a basic block in a hot partition. Â */
2764 2984211 : if (crtl->has_bb_partition && !err
2765 101967742 : && current_ir_type () == IR_RTL_CFGLAYOUT)
2766 : {
2767 123373 : auto_vec<basic_block> bbs_to_fix = find_partition_fixes (true);
2768 246746 : err = !bbs_to_fix.is_empty ();
2769 123373 : }
2770 :
2771 : /* Clean up. */
2772 98983531 : return err;
2773 : }
2774 :
2775 : /* Checks on the instructions within blocks. Currently checks that each
2776 : block starts with a basic block note, and that basic block notes and
2777 : control flow jumps are not found in the middle of the block. */
2778 :
2779 : static bool
2780 98983531 : rtl_verify_bb_insns (void)
2781 : {
2782 98983531 : rtx_insn *x;
2783 98983531 : bool err = false;
2784 98983531 : basic_block bb;
2785 :
2786 1179629870 : FOR_EACH_BB_REVERSE_FN (bb, cfun)
2787 : {
2788 : /* Now check the header of basic
2789 : block. It ought to contain optional CODE_LABEL followed
2790 : by NOTE_BASIC_BLOCK. */
2791 1080646339 : x = BB_HEAD (bb);
2792 1080646339 : if (LABEL_P (x))
2793 : {
2794 521685867 : if (BB_END (bb) == x)
2795 : {
2796 0 : error ("NOTE_INSN_BASIC_BLOCK is missing for block %d",
2797 : bb->index);
2798 0 : err = true;
2799 : }
2800 :
2801 521685867 : x = NEXT_INSN (x);
2802 : }
2803 :
2804 1080646339 : if (!NOTE_INSN_BASIC_BLOCK_P (x) || NOTE_BASIC_BLOCK (x) != bb)
2805 : {
2806 0 : error ("NOTE_INSN_BASIC_BLOCK is missing for block %d",
2807 : bb->index);
2808 0 : err = true;
2809 : }
2810 :
2811 1080646339 : if (BB_END (bb) == x)
2812 : /* Do checks for empty blocks here. */
2813 : ;
2814 : else
2815 12152020099 : for (x = NEXT_INSN (x); x; x = NEXT_INSN (x))
2816 : {
2817 11089879159 : if (NOTE_INSN_BASIC_BLOCK_P (x))
2818 : {
2819 0 : error ("NOTE_INSN_BASIC_BLOCK %d in middle of basic block %d",
2820 0 : INSN_UID (x), bb->index);
2821 0 : err = true;
2822 : }
2823 :
2824 11089879159 : if (x == BB_END (bb))
2825 : break;
2826 :
2827 10027738219 : if (control_flow_insn_p (x))
2828 : {
2829 0 : error ("in basic block %d:", bb->index);
2830 0 : fatal_insn ("flow control insn inside a basic block", x);
2831 : }
2832 : }
2833 : }
2834 :
2835 : /* Clean up. */
2836 98983531 : return err;
2837 : }
2838 :
2839 : /* Verify that block pointers for instructions in basic blocks, headers and
2840 : footers are set appropriately. */
2841 :
2842 : static bool
2843 98983531 : rtl_verify_bb_pointers (void)
2844 : {
2845 98983531 : bool err = false;
2846 98983531 : basic_block bb;
2847 :
2848 : /* Check the general integrity of the basic blocks. */
2849 1179629870 : FOR_EACH_BB_REVERSE_FN (bb, cfun)
2850 : {
2851 1080646339 : rtx_insn *insn;
2852 :
2853 1080646339 : if (!(bb->flags & BB_RTL))
2854 : {
2855 0 : error ("BB_RTL flag not set for block %d", bb->index);
2856 0 : err = true;
2857 : }
2858 :
2859 13772857704 : FOR_BB_INSNS (bb, insn)
2860 12692211365 : if (BLOCK_FOR_INSN (insn) != bb)
2861 : {
2862 0 : error ("insn %d basic block pointer is %d, should be %d",
2863 0 : INSN_UID (insn),
2864 0 : BLOCK_FOR_INSN (insn) ? BLOCK_FOR_INSN (insn)->index : 0,
2865 : bb->index);
2866 0 : err = true;
2867 : }
2868 :
2869 1081201102 : for (insn = BB_HEADER (bb); insn; insn = NEXT_INSN (insn))
2870 554763 : if (!BARRIER_P (insn)
2871 554763 : && BLOCK_FOR_INSN (insn) != NULL)
2872 : {
2873 0 : error ("insn %d in header of bb %d has non-NULL basic block",
2874 0 : INSN_UID (insn), bb->index);
2875 0 : err = true;
2876 : }
2877 1109347727 : for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn))
2878 28701388 : if (!BARRIER_P (insn)
2879 28701388 : && BLOCK_FOR_INSN (insn) != NULL)
2880 : {
2881 0 : error ("insn %d in footer of bb %d has non-NULL basic block",
2882 0 : INSN_UID (insn), bb->index);
2883 0 : err = true;
2884 : }
2885 : }
2886 :
2887 : /* Clean up. */
2888 98983531 : return err;
2889 : }
2890 :
2891 : /* Verify the CFG and RTL consistency common for both underlying RTL and
2892 : cfglayout RTL.
2893 :
2894 : Currently it does following checks:
2895 :
2896 : - overlapping of basic blocks
2897 : - insns with wrong BLOCK_FOR_INSN pointers
2898 : - headers of basic blocks (the NOTE_INSN_BASIC_BLOCK note)
2899 : - tails of basic blocks (ensure that boundary is necessary)
2900 : - scans body of the basic block for JUMP_INSN, CODE_LABEL
2901 : and NOTE_INSN_BASIC_BLOCK
2902 : - verify that no fall_thru edge crosses hot/cold partition boundaries
2903 : - verify that there are no pending RTL branch predictions
2904 : - verify that hot blocks are not dominated by cold blocks
2905 :
2906 : In future it can be extended check a lot of other stuff as well
2907 : (reachability of basic blocks, life information, etc. etc.). */
2908 :
2909 : static bool
2910 98983531 : rtl_verify_flow_info_1 (void)
2911 : {
2912 98983531 : bool err = false;
2913 :
2914 98983531 : if (rtl_verify_bb_pointers ())
2915 : err = true;
2916 :
2917 98983531 : if (rtl_verify_bb_insns ())
2918 0 : err = true;
2919 :
2920 98983531 : if (rtl_verify_edges ())
2921 0 : err = true;
2922 :
2923 98983531 : return err;
2924 : }
2925 :
2926 : /* Walk the instruction chain and verify that bb head/end pointers
2927 : are correct, and that instructions are in exactly one bb and have
2928 : correct block pointers. */
2929 :
2930 : static bool
2931 62618957 : rtl_verify_bb_insn_chain (void)
2932 : {
2933 62618957 : basic_block bb;
2934 62618957 : bool err = false;
2935 62618957 : rtx_insn *x;
2936 62618957 : rtx_insn *last_head = get_last_insn ();
2937 62618957 : basic_block *bb_info;
2938 62618957 : const int max_uid = get_max_uid ();
2939 :
2940 62618957 : bb_info = XCNEWVEC (basic_block, max_uid);
2941 :
2942 723807246 : FOR_EACH_BB_REVERSE_FN (bb, cfun)
2943 : {
2944 661188289 : rtx_insn *head = BB_HEAD (bb);
2945 661188289 : rtx_insn *end = BB_END (bb);
2946 :
2947 919262425 : for (x = last_head; x != NULL_RTX; x = PREV_INSN (x))
2948 : {
2949 : /* Verify the end of the basic block is in the INSN chain. */
2950 919262425 : if (x == end)
2951 : break;
2952 :
2953 : /* And that the code outside of basic blocks has NULL bb field. */
2954 258074136 : if (!BARRIER_P (x)
2955 258074136 : && BLOCK_FOR_INSN (x) != NULL)
2956 : {
2957 0 : error ("insn %d outside of basic blocks has non-NULL bb field",
2958 0 : INSN_UID (x));
2959 0 : err = true;
2960 : }
2961 : }
2962 :
2963 661188289 : if (!x)
2964 : {
2965 0 : error ("end insn %d for block %d not found in the insn stream",
2966 0 : INSN_UID (end), bb->index);
2967 0 : err = true;
2968 : }
2969 :
2970 : /* Work backwards from the end to the head of the basic block
2971 : to verify the head is in the RTL chain. */
2972 7735212243 : for (; x != NULL_RTX; x = PREV_INSN (x))
2973 : {
2974 : /* While walking over the insn chain, verify insns appear
2975 : in only one basic block. */
2976 7735212243 : if (bb_info[INSN_UID (x)] != NULL)
2977 : {
2978 0 : error ("insn %d is in multiple basic blocks (%d and %d)",
2979 : INSN_UID (x), bb->index, bb_info[INSN_UID (x)]->index);
2980 0 : err = true;
2981 : }
2982 :
2983 7735212243 : bb_info[INSN_UID (x)] = bb;
2984 :
2985 7735212243 : if (x == head)
2986 : break;
2987 : }
2988 661188289 : if (!x)
2989 : {
2990 0 : error ("head insn %d for block %d not found in the insn stream",
2991 0 : INSN_UID (head), bb->index);
2992 0 : err = true;
2993 : }
2994 :
2995 661188289 : last_head = PREV_INSN (x);
2996 : }
2997 :
2998 126264331 : for (x = last_head; x != NULL_RTX; x = PREV_INSN (x))
2999 : {
3000 : /* Check that the code before the first basic block has NULL
3001 : bb field. */
3002 63645374 : if (!BARRIER_P (x)
3003 63645374 : && BLOCK_FOR_INSN (x) != NULL)
3004 : {
3005 0 : error ("insn %d outside of basic blocks has non-NULL bb field",
3006 0 : INSN_UID (x));
3007 0 : err = true;
3008 : }
3009 : }
3010 62618957 : free (bb_info);
3011 :
3012 62618957 : return err;
3013 : }
3014 :
3015 : /* Verify that fallthru edges point to adjacent blocks in layout order and
3016 : that barriers exist after non-fallthru blocks. */
3017 :
3018 : static bool
3019 62618957 : rtl_verify_fallthru (void)
3020 : {
3021 62618957 : basic_block bb;
3022 62618957 : bool err = false;
3023 :
3024 723807246 : FOR_EACH_BB_REVERSE_FN (bb, cfun)
3025 : {
3026 661188289 : edge e;
3027 :
3028 661188289 : e = find_fallthru_edge (bb->succs);
3029 661188289 : if (!e)
3030 : {
3031 192377892 : rtx_insn *insn;
3032 :
3033 : /* Ensure existence of barrier in BB with no fallthru edges. */
3034 192924184 : for (insn = NEXT_INSN (BB_END (bb)); ; insn = NEXT_INSN (insn))
3035 : {
3036 192924184 : if (!insn || NOTE_INSN_BASIC_BLOCK_P (insn))
3037 : {
3038 0 : error ("missing barrier after block %i", bb->index);
3039 0 : err = true;
3040 0 : break;
3041 : }
3042 192924184 : if (BARRIER_P (insn))
3043 : break;
3044 : }
3045 : }
3046 468810397 : else if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
3047 468810397 : && e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
3048 : {
3049 438795257 : rtx_insn *insn;
3050 :
3051 438795257 : if (e->src->next_bb != e->dest)
3052 : {
3053 0 : error
3054 0 : ("verify_flow_info: Incorrect blocks for fallthru %i->%i",
3055 : e->src->index, e->dest->index);
3056 0 : err = true;
3057 : }
3058 : else
3059 884236900 : for (insn = NEXT_INSN (BB_END (e->src)); insn != BB_HEAD (e->dest);
3060 6646386 : insn = NEXT_INSN (insn))
3061 6646386 : if (BARRIER_P (insn) || NONDEBUG_INSN_P (insn))
3062 : {
3063 0 : error ("verify_flow_info: Incorrect fallthru %i->%i",
3064 0 : e->src->index, e->dest->index);
3065 0 : error ("wrong insn in the fallthru edge");
3066 0 : debug_rtx (insn);
3067 0 : err = true;
3068 : }
3069 : }
3070 : }
3071 :
3072 62618957 : return err;
3073 : }
3074 :
3075 : /* Verify that blocks are laid out in consecutive order. While walking the
3076 : instructions, verify that all expected instructions are inside the basic
3077 : blocks, and that all returns are followed by barriers. */
3078 :
3079 : static bool
3080 62618957 : rtl_verify_bb_layout (void)
3081 : {
3082 62618957 : basic_block bb;
3083 62618957 : bool err = false;
3084 62618957 : rtx_insn *x, *y;
3085 62618957 : int num_bb_notes;
3086 62618957 : rtx_insn * const rtx_first = get_insns ();
3087 62618957 : basic_block last_bb_seen = ENTRY_BLOCK_PTR_FOR_FN (cfun), curr_bb = NULL;
3088 :
3089 62618957 : num_bb_notes = 0;
3090 :
3091 8119130536 : for (x = rtx_first; x; x = NEXT_INSN (x))
3092 : {
3093 8056511579 : if (NOTE_INSN_BASIC_BLOCK_P (x))
3094 : {
3095 661188289 : bb = NOTE_BASIC_BLOCK (x);
3096 :
3097 661188289 : num_bb_notes++;
3098 661188289 : if (bb != last_bb_seen->next_bb)
3099 0 : internal_error ("basic blocks not laid down consecutively");
3100 :
3101 : curr_bb = last_bb_seen = bb;
3102 : }
3103 :
3104 8056511579 : if (!curr_bb)
3105 : {
3106 634688579 : switch (GET_CODE (x))
3107 : {
3108 : case BARRIER:
3109 : case NOTE:
3110 : break;
3111 :
3112 313809417 : case CODE_LABEL:
3113 : /* An ADDR_VEC is placed outside any basic block. */
3114 313809417 : if (NEXT_INSN (x)
3115 313809417 : && JUMP_TABLE_DATA_P (NEXT_INSN (x)))
3116 : x = NEXT_INSN (x);
3117 :
3118 : /* But in any case, non-deletable labels can appear anywhere. */
3119 : break;
3120 :
3121 0 : default:
3122 0 : fatal_insn ("insn outside basic block", x);
3123 : }
3124 : }
3125 :
3126 8056511579 : if (JUMP_P (x)
3127 443435765 : && returnjump_p (x) && ! condjump_p (x)
3128 8087849029 : && ! ((y = next_nonnote_nondebug_insn (x))
3129 31337450 : && BARRIER_P (y)))
3130 0 : fatal_insn ("return not followed by barrier", x);
3131 :
3132 8056511579 : if (curr_bb && x == BB_END (curr_bb))
3133 1295876868 : curr_bb = NULL;
3134 : }
3135 :
3136 62618957 : if (num_bb_notes != n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS)
3137 0 : internal_error
3138 0 : ("number of bb notes in insn chain (%d) != n_basic_blocks (%d)",
3139 : num_bb_notes, n_basic_blocks_for_fn (cfun));
3140 :
3141 62618957 : return err;
3142 : }
3143 :
3144 : /* Verify the CFG and RTL consistency common for both underlying RTL and
3145 : cfglayout RTL, plus consistency checks specific to linearized RTL mode.
3146 :
3147 : Currently it does following checks:
3148 : - all checks of rtl_verify_flow_info_1
3149 : - test head/end pointers
3150 : - check that blocks are laid out in consecutive order
3151 : - check that all insns are in the basic blocks
3152 : (except the switch handling code, barriers and notes)
3153 : - check that all returns are followed by barriers
3154 : - check that all fallthru edge points to the adjacent blocks
3155 : - verify that there is a single hot/cold partition boundary after bbro */
3156 :
3157 : static bool
3158 62618957 : rtl_verify_flow_info (void)
3159 : {
3160 62618957 : bool err = false;
3161 :
3162 62618957 : if (rtl_verify_flow_info_1 ())
3163 : err = true;
3164 :
3165 62618957 : if (rtl_verify_bb_insn_chain ())
3166 0 : err = true;
3167 :
3168 62618957 : if (rtl_verify_fallthru ())
3169 0 : err = true;
3170 :
3171 62618957 : if (rtl_verify_bb_layout ())
3172 : err = true;
3173 :
3174 62618957 : if (verify_hot_cold_block_grouping ())
3175 0 : err = true;
3176 :
3177 62618957 : return err;
3178 : }
3179 :
3180 : /* Assume that the preceding pass has possibly eliminated jump instructions
3181 : or converted the unconditional jumps. Eliminate the edges from CFG.
3182 : Return true if any edges are eliminated. */
3183 :
3184 : bool
3185 72495431 : purge_dead_edges (basic_block bb)
3186 : {
3187 72495431 : edge e;
3188 72495431 : rtx_insn *insn = BB_END (bb);
3189 72495431 : rtx note;
3190 72495431 : bool purged = false;
3191 72495431 : bool found;
3192 72495431 : edge_iterator ei;
3193 :
3194 72495431 : if ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb))
3195 16646769 : do
3196 16646769 : insn = PREV_INSN (insn);
3197 16646769 : while ((DEBUG_INSN_P (insn) || NOTE_P (insn)) && insn != BB_HEAD (bb));
3198 :
3199 : /* If this instruction cannot trap, remove REG_EH_REGION notes. */
3200 72495431 : if (NONJUMP_INSN_P (insn)
3201 72495431 : && (note = find_reg_note (insn, REG_EH_REGION, NULL)))
3202 : {
3203 1263604 : rtx eqnote;
3204 :
3205 1263604 : if (! may_trap_p (PATTERN (insn))
3206 1263604 : || ((eqnote = find_reg_equal_equiv_note (insn))
3207 164 : && ! may_trap_p (XEXP (eqnote, 0))))
3208 44017 : remove_note (insn, note);
3209 : }
3210 : /* A tail call cannot trap either. The tailc/musttail pass could have
3211 : allowed a tail call if it could throw internally, but perform no
3212 : actual statements and then caused the exception to be thrown externally
3213 : in the hope that it is cleaned up later. If it is not, just
3214 : remove REG_EH_REGION note. While the call maybe can throw, the
3215 : current function's frame will not be there anymore when it does. */
3216 72495431 : if (CALL_P (insn)
3217 8874705 : && SIBLING_CALL_P (insn)
3218 73018769 : && (note = find_reg_note (insn, REG_EH_REGION, NULL)))
3219 84434 : remove_note (insn, note);
3220 :
3221 : /* Cleanup abnormal edges caused by exceptions or non-local gotos. */
3222 174080870 : for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
3223 : {
3224 101585439 : bool remove = false;
3225 :
3226 : /* There are three types of edges we need to handle correctly here: EH
3227 : edges, abnormal call EH edges, and abnormal call non-EH edges. The
3228 : latter can appear when nonlocal gotos are used. */
3229 101585439 : if (e->flags & EDGE_ABNORMAL_CALL)
3230 : {
3231 3170765 : if (!CALL_P (insn))
3232 : remove = true;
3233 3170760 : else if (can_nonlocal_goto (insn))
3234 : ;
3235 3094719 : else if ((e->flags & EDGE_EH) && can_throw_internal (insn))
3236 : ;
3237 0 : else if (flag_tm && find_reg_note (insn, REG_TM, NULL))
3238 : ;
3239 : else
3240 : remove = true;
3241 : }
3242 98414674 : else if (e->flags & EDGE_EH)
3243 1842285 : remove = !can_throw_internal (insn);
3244 :
3245 1842285 : if (remove)
3246 : {
3247 381853 : remove_edge (e);
3248 381853 : df_set_bb_dirty (bb);
3249 381853 : purged = true;
3250 : }
3251 : else
3252 101203586 : ei_next (&ei);
3253 : }
3254 :
3255 72495431 : if (JUMP_P (insn))
3256 : {
3257 39119103 : rtx note;
3258 39119103 : edge b,f;
3259 39119103 : edge_iterator ei;
3260 :
3261 : /* We do care only about conditional jumps and simplejumps. */
3262 39119103 : if (!any_condjump_p (insn)
3263 12445312 : && !returnjump_p (insn)
3264 48045037 : && !simplejump_p (insn))
3265 : return purged;
3266 :
3267 : /* Branch probability/prediction notes are defined only for
3268 : condjumps. We've possibly turned condjump into simplejump. */
3269 39075634 : if (simplejump_p (insn))
3270 : {
3271 8882465 : note = find_reg_note (insn, REG_BR_PROB, NULL);
3272 8882465 : if (note)
3273 4175 : remove_note (insn, note);
3274 8882465 : while ((note = find_reg_note (insn, REG_BR_PRED, NULL)))
3275 0 : remove_note (insn, note);
3276 : }
3277 :
3278 104832703 : for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
3279 : {
3280 : /* Avoid abnormal flags to leak from computed jumps turned
3281 : into simplejumps. */
3282 :
3283 65757069 : e->flags &= ~EDGE_ABNORMAL;
3284 :
3285 : /* See if this edge is one we should keep. */
3286 65757069 : if ((e->flags & EDGE_FALLTHRU) && any_condjump_p (insn))
3287 : /* A conditional jump can fall through into the next
3288 : block, so we should keep the edge. */
3289 : {
3290 26673791 : ei_next (&ei);
3291 26673791 : continue;
3292 : }
3293 39083278 : else if (e->dest != EXIT_BLOCK_PTR_FOR_FN (cfun)
3294 35563900 : && BB_HEAD (e->dest) == JUMP_LABEL (insn))
3295 : /* If the destination block is the target of the jump,
3296 : keep the edge. */
3297 : {
3298 35555230 : ei_next (&ei);
3299 35555230 : continue;
3300 : }
3301 7047426 : else if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun)
3302 3528048 : && returnjump_p (insn))
3303 : /* If the destination block is the exit block, and this
3304 : instruction is a return, then keep the edge. */
3305 : {
3306 3519378 : ei_next (&ei);
3307 3519378 : continue;
3308 : }
3309 8670 : else if ((e->flags & EDGE_EH) && can_throw_internal (insn))
3310 : /* Keep the edges that correspond to exceptions thrown by
3311 : this instruction and rematerialize the EDGE_ABNORMAL
3312 : flag we just cleared above. */
3313 : {
3314 0 : e->flags |= EDGE_ABNORMAL;
3315 0 : ei_next (&ei);
3316 0 : continue;
3317 : }
3318 :
3319 : /* We do not need this edge. */
3320 8670 : df_set_bb_dirty (bb);
3321 8670 : purged = true;
3322 8670 : remove_edge (e);
3323 : }
3324 :
3325 39258754 : if (EDGE_COUNT (bb->succs) == 0 || !purged)
3326 : return purged;
3327 :
3328 139651 : if (dump_file)
3329 0 : fprintf (dump_file, "Purged edges from bb %i\n", bb->index);
3330 :
3331 139651 : if (!optimize)
3332 : return purged;
3333 :
3334 : /* Redistribute probabilities. */
3335 139098 : if (single_succ_p (bb))
3336 : {
3337 139098 : single_succ_edge (bb)->probability = profile_probability::always ();
3338 : }
3339 : else
3340 : {
3341 0 : note = find_reg_note (insn, REG_BR_PROB, NULL);
3342 0 : if (!note)
3343 : return purged;
3344 :
3345 0 : b = BRANCH_EDGE (bb);
3346 0 : f = FALLTHRU_EDGE (bb);
3347 0 : b->probability = profile_probability::from_reg_br_prob_note
3348 0 : (XINT (note, 0));
3349 0 : f->probability = b->probability.invert ();
3350 : }
3351 :
3352 139098 : return purged;
3353 : }
3354 33376328 : else if (CALL_P (insn) && SIBLING_CALL_P (insn))
3355 : {
3356 : /* First, there should not be any EH or ABCALL edges resulting
3357 : from non-local gotos and the like. If there were, we shouldn't
3358 : have created the sibcall in the first place. Second, there
3359 : should of course never have been a fallthru edge. */
3360 523338 : gcc_assert (single_succ_p (bb));
3361 523338 : gcc_assert (single_succ_edge (bb)->flags
3362 : == (EDGE_SIBCALL | EDGE_ABNORMAL));
3363 :
3364 : return false;
3365 : }
3366 :
3367 : /* If we don't see a jump insn, we don't know exactly why the block would
3368 : have been broken at this point. Look for a simple, non-fallthru edge,
3369 : as these are only created by conditional branches. If we find such an
3370 : edge we know that there used to be a jump here and can then safely
3371 : remove all non-fallthru edges. */
3372 32852990 : found = false;
3373 67013204 : FOR_EACH_EDGE (e, ei, bb->succs)
3374 34436429 : if (! (e->flags & (EDGE_COMPLEX | EDGE_FALLTHRU)))
3375 : {
3376 : found = true;
3377 : break;
3378 : }
3379 :
3380 32852990 : if (!found)
3381 : return purged;
3382 :
3383 : /* Remove all but the fake and fallthru edges. The fake edge may be
3384 : the only successor for this block in the case of noreturn
3385 : calls. */
3386 828777 : for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
3387 : {
3388 552562 : if (!(e->flags & (EDGE_FALLTHRU | EDGE_FAKE)))
3389 : {
3390 276347 : df_set_bb_dirty (bb);
3391 276347 : remove_edge (e);
3392 276347 : purged = true;
3393 : }
3394 : else
3395 276215 : ei_next (&ei);
3396 : }
3397 :
3398 276215 : gcc_assert (single_succ_p (bb));
3399 :
3400 276215 : single_succ_edge (bb)->probability = profile_probability::always ();
3401 :
3402 276215 : if (dump_file)
3403 1 : fprintf (dump_file, "Purged non-fallthru edges from bb %i\n",
3404 : bb->index);
3405 : return purged;
3406 : }
3407 :
3408 : /* Search all basic blocks for potentially dead edges and purge them. Return
3409 : true if some edge has been eliminated. */
3410 :
3411 : bool
3412 3297980 : purge_all_dead_edges (void)
3413 : {
3414 3297980 : bool purged = false;
3415 3297980 : basic_block bb;
3416 :
3417 47497343 : FOR_EACH_BB_FN (bb, cfun)
3418 44199363 : if (purge_dead_edges (bb))
3419 2714 : purged = true;
3420 :
3421 3297980 : return purged;
3422 : }
3423 :
3424 : /* This is used by a few passes that emit some instructions after abnormal
3425 : calls, moving the basic block's end, while they in fact do want to emit
3426 : them on the fallthru edge. Look for abnormal call edges, find backward
3427 : the call in the block and insert the instructions on the edge instead.
3428 :
3429 : Similarly, handle instructions throwing exceptions internally.
3430 :
3431 : Return true when instructions have been found and inserted on edges. */
3432 :
3433 : bool
3434 1506197 : fixup_abnormal_edges (void)
3435 : {
3436 1506197 : bool inserted = false;
3437 1506197 : basic_block bb;
3438 :
3439 17146526 : FOR_EACH_BB_FN (bb, cfun)
3440 : {
3441 15640329 : edge e;
3442 15640329 : edge_iterator ei;
3443 :
3444 : /* Look for cases we are interested in - calls or instructions causing
3445 : exceptions. */
3446 36888307 : FOR_EACH_EDGE (e, ei, bb->succs)
3447 21927200 : if ((e->flags & EDGE_ABNORMAL_CALL)
3448 21358531 : || ((e->flags & (EDGE_ABNORMAL | EDGE_EH))
3449 : == (EDGE_ABNORMAL | EDGE_EH)))
3450 : break;
3451 :
3452 15640329 : if (e && !CALL_P (BB_END (bb)) && !can_throw_internal (BB_END (bb)))
3453 : {
3454 9405 : rtx_insn *insn;
3455 :
3456 : /* Get past the new insns generated. Allow notes, as the insns
3457 : may be already deleted. */
3458 9405 : insn = BB_END (bb);
3459 16059 : while ((NONJUMP_INSN_P (insn) || NOTE_P (insn))
3460 15152 : && !can_throw_internal (insn)
3461 28654 : && insn != BB_HEAD (bb))
3462 8028 : insn = PREV_INSN (insn);
3463 :
3464 9405 : if (CALL_P (insn) || can_throw_internal (insn))
3465 : {
3466 6203 : rtx_insn *stop, *next;
3467 :
3468 6203 : e = find_fallthru_edge (bb->succs);
3469 :
3470 6203 : stop = NEXT_INSN (BB_END (bb));
3471 6203 : BB_END (bb) = insn;
3472 :
3473 20233 : for (insn = NEXT_INSN (insn); insn != stop; insn = next)
3474 : {
3475 7827 : next = NEXT_INSN (insn);
3476 7827 : if (INSN_P (insn))
3477 : {
3478 6694 : delete_insn (insn);
3479 :
3480 : /* Sometimes there's still the return value USE.
3481 : If it's placed after a trapping call (i.e. that
3482 : call is the last insn anyway), we have no fallthru
3483 : edge. Simply delete this use and don't try to insert
3484 : on the non-existent edge.
3485 : Similarly, sometimes a call that can throw is
3486 : followed in the source with __builtin_unreachable (),
3487 : meaning that there is UB if the call returns rather
3488 : than throws. If there weren't any instructions
3489 : following such calls before, supposedly even the ones
3490 : we've deleted aren't significant and can be
3491 : removed. */
3492 6694 : if (e)
3493 : {
3494 : /* We're not deleting it, we're moving it. */
3495 6693 : insn->set_undeleted ();
3496 6693 : SET_PREV_INSN (insn) = NULL_RTX;
3497 6693 : SET_NEXT_INSN (insn) = NULL_RTX;
3498 :
3499 6693 : insert_insn_on_edge (insn, e);
3500 6693 : inserted = true;
3501 : }
3502 : }
3503 1133 : else if (!BARRIER_P (insn))
3504 1133 : set_block_for_insn (insn, NULL);
3505 : }
3506 : }
3507 :
3508 : /* It may be that we don't find any trapping insn. In this
3509 : case we discovered quite late that the insn that had been
3510 : marked as can_throw_internal in fact couldn't trap at all.
3511 : So we should in fact delete the EH edges out of the block. */
3512 : else
3513 3202 : purge_dead_edges (bb);
3514 : }
3515 : }
3516 :
3517 1506197 : return inserted;
3518 : }
3519 :
3520 : /* Delete the unconditional jump INSN and adjust the CFG correspondingly.
3521 : Note that the INSN should be deleted *after* removing dead edges, so
3522 : that the kept edge is the fallthrough edge for a (set (pc) (pc))
3523 : but not for a (set (pc) (label_ref FOO)). */
3524 :
3525 : void
3526 4508 : update_cfg_for_uncondjump (rtx_insn *insn)
3527 : {
3528 4508 : basic_block bb = BLOCK_FOR_INSN (insn);
3529 4508 : gcc_assert (BB_END (bb) == insn);
3530 :
3531 4508 : purge_dead_edges (bb);
3532 :
3533 4508 : if (current_ir_type () != IR_RTL_CFGLAYOUT)
3534 : {
3535 35 : if (!find_fallthru_edge (bb->succs))
3536 : {
3537 35 : auto barrier = next_nonnote_nondebug_insn (insn);
3538 35 : if (!barrier || !BARRIER_P (barrier))
3539 35 : emit_barrier_after (insn);
3540 : }
3541 35 : return;
3542 : }
3543 :
3544 4473 : delete_insn (insn);
3545 4473 : if (EDGE_COUNT (bb->succs) == 1)
3546 : {
3547 2065 : rtx_insn *insn;
3548 :
3549 2065 : single_succ_edge (bb)->flags |= EDGE_FALLTHRU;
3550 :
3551 : /* Remove barriers from the footer if there are any. */
3552 2066 : for (insn = BB_FOOTER (bb); insn; insn = NEXT_INSN (insn))
3553 1 : if (BARRIER_P (insn))
3554 : {
3555 1 : if (PREV_INSN (insn))
3556 0 : SET_NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn);
3557 : else
3558 1 : BB_FOOTER (bb) = NEXT_INSN (insn);
3559 1 : if (NEXT_INSN (insn))
3560 0 : SET_PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn);
3561 : }
3562 0 : else if (LABEL_P (insn))
3563 : break;
3564 : }
3565 : }
3566 :
3567 : /* Cut the insns from FIRST to LAST out of the insns stream. */
3568 :
3569 : rtx_insn *
3570 11898639 : unlink_insn_chain (rtx_insn *first, rtx_insn *last)
3571 : {
3572 11898639 : rtx_insn *prevfirst = PREV_INSN (first);
3573 11898639 : rtx_insn *nextlast = NEXT_INSN (last);
3574 :
3575 11898639 : SET_PREV_INSN (first) = NULL;
3576 11898639 : SET_NEXT_INSN (last) = NULL;
3577 11898639 : if (prevfirst)
3578 9383298 : SET_NEXT_INSN (prevfirst) = nextlast;
3579 11898639 : if (nextlast)
3580 10443726 : SET_PREV_INSN (nextlast) = prevfirst;
3581 : else
3582 1454913 : set_last_insn (prevfirst);
3583 11898639 : if (!prevfirst)
3584 2515341 : set_first_insn (nextlast);
3585 11898639 : return first;
3586 : }
3587 :
3588 : /* Skip over inter-block insns occurring after BB which are typically
3589 : associated with BB (e.g., barriers). If there are any such insns,
3590 : we return the last one. Otherwise, we return the end of BB. */
3591 :
3592 : static rtx_insn *
3593 26537190 : skip_insns_after_block (basic_block bb)
3594 : {
3595 26537190 : rtx_insn *insn, *last_insn, *next_head, *prev;
3596 :
3597 26537190 : next_head = NULL;
3598 26537190 : if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun))
3599 24021834 : next_head = BB_HEAD (bb->next_bb);
3600 :
3601 35326526 : for (last_insn = insn = BB_END (bb); (insn = NEXT_INSN (insn)) != 0; )
3602 : {
3603 32811170 : if (insn == next_head)
3604 : break;
3605 :
3606 8789336 : switch (GET_CODE (insn))
3607 : {
3608 7697477 : case BARRIER:
3609 7697477 : last_insn = insn;
3610 7697477 : continue;
3611 :
3612 1075816 : case NOTE:
3613 1075816 : gcc_assert (NOTE_KIND (insn) != NOTE_INSN_BLOCK_END);
3614 1075816 : continue;
3615 :
3616 16043 : case CODE_LABEL:
3617 16043 : if (NEXT_INSN (insn)
3618 16043 : && JUMP_TABLE_DATA_P (NEXT_INSN (insn)))
3619 : {
3620 16043 : insn = NEXT_INSN (insn);
3621 16043 : last_insn = insn;
3622 16043 : continue;
3623 : }
3624 : break;
3625 :
3626 : default:
3627 : break;
3628 : }
3629 :
3630 : break;
3631 : }
3632 :
3633 : /* It is possible to hit contradictory sequence. For instance:
3634 :
3635 : jump_insn
3636 : NOTE_INSN_BLOCK_BEG
3637 : barrier
3638 :
3639 : Where barrier belongs to jump_insn, but the note does not. This can be
3640 : created by removing the basic block originally following
3641 : NOTE_INSN_BLOCK_BEG. In such case reorder the notes. */
3642 :
3643 34266894 : for (insn = last_insn; insn != BB_END (bb); insn = prev)
3644 : {
3645 7729704 : prev = PREV_INSN (insn);
3646 7729704 : if (NOTE_P (insn))
3647 141 : switch (NOTE_KIND (insn))
3648 : {
3649 0 : case NOTE_INSN_BLOCK_END:
3650 0 : gcc_unreachable ();
3651 141 : break;
3652 141 : case NOTE_INSN_DELETED:
3653 141 : case NOTE_INSN_DELETED_LABEL:
3654 141 : case NOTE_INSN_DELETED_DEBUG_LABEL:
3655 141 : continue;
3656 0 : default:
3657 0 : reorder_insns (insn, insn, last_insn);
3658 : }
3659 : }
3660 :
3661 26537190 : return last_insn;
3662 : }
3663 :
3664 : /* Locate or create a label for a given basic block. */
3665 :
3666 : static rtx_insn *
3667 2280795 : label_for_bb (basic_block bb)
3668 : {
3669 2280795 : rtx_insn *label = BB_HEAD (bb);
3670 :
3671 2280795 : if (!LABEL_P (label))
3672 : {
3673 1452525 : if (dump_file)
3674 8 : fprintf (dump_file, "Emitting label for block %d\n", bb->index);
3675 :
3676 1452525 : label = block_label (bb);
3677 : }
3678 :
3679 2280795 : return label;
3680 : }
3681 :
3682 : /* Locate the effective beginning and end of the insn chain for each
3683 : block, as defined by skip_insns_after_block above. */
3684 :
3685 : static void
3686 2515356 : record_effective_endpoints (void)
3687 : {
3688 2515356 : rtx_insn *next_insn;
3689 2515356 : basic_block bb;
3690 2515356 : rtx_insn *insn;
3691 :
3692 2515356 : for (insn = get_insns ();
3693 : insn
3694 5033332 : && NOTE_P (insn)
3695 10065555 : && NOTE_KIND (insn) != NOTE_INSN_BASIC_BLOCK;
3696 2517976 : insn = NEXT_INSN (insn))
3697 2517976 : continue;
3698 : /* No basic blocks at all? */
3699 2515356 : gcc_assert (insn);
3700 :
3701 2515356 : if (PREV_INSN (insn))
3702 2515341 : cfg_layout_function_header =
3703 2515341 : unlink_insn_chain (get_insns (), PREV_INSN (insn));
3704 : else
3705 15 : cfg_layout_function_header = NULL;
3706 :
3707 2515356 : next_insn = get_insns ();
3708 29052546 : FOR_EACH_BB_FN (bb, cfun)
3709 : {
3710 26537190 : rtx_insn *end;
3711 :
3712 26537190 : if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb))
3713 45825 : BB_HEADER (bb) = unlink_insn_chain (next_insn,
3714 45825 : PREV_INSN (BB_HEAD (bb)));
3715 26537190 : end = skip_insns_after_block (bb);
3716 26537190 : if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end)
3717 7617773 : BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end);
3718 26537190 : next_insn = NEXT_INSN (BB_END (bb));
3719 : }
3720 :
3721 2515356 : cfg_layout_function_footer = next_insn;
3722 2515356 : if (cfg_layout_function_footer)
3723 1019684 : cfg_layout_function_footer = unlink_insn_chain (cfg_layout_function_footer, get_last_insn ());
3724 2517976 : }
3725 :
3726 : namespace {
3727 :
3728 : const pass_data pass_data_into_cfg_layout_mode =
3729 : {
3730 : RTL_PASS, /* type */
3731 : "into_cfglayout", /* name */
3732 : OPTGROUP_NONE, /* optinfo_flags */
3733 : TV_CFG, /* tv_id */
3734 : 0, /* properties_required */
3735 : PROP_cfglayout, /* properties_provided */
3736 : 0, /* properties_destroyed */
3737 : 0, /* todo_flags_start */
3738 : 0, /* todo_flags_finish */
3739 : };
3740 :
3741 : class pass_into_cfg_layout_mode : public rtl_opt_pass
3742 : {
3743 : public:
3744 285722 : pass_into_cfg_layout_mode (gcc::context *ctxt)
3745 571444 : : rtl_opt_pass (pass_data_into_cfg_layout_mode, ctxt)
3746 : {}
3747 :
3748 : /* opt_pass methods: */
3749 1471359 : unsigned int execute (function *) final override
3750 : {
3751 1471359 : cfg_layout_initialize (0);
3752 1471359 : return 0;
3753 : }
3754 :
3755 : }; // class pass_into_cfg_layout_mode
3756 :
3757 : } // anon namespace
3758 :
3759 : rtl_opt_pass *
3760 285722 : make_pass_into_cfg_layout_mode (gcc::context *ctxt)
3761 : {
3762 285722 : return new pass_into_cfg_layout_mode (ctxt);
3763 : }
3764 :
3765 : namespace {
3766 :
3767 : const pass_data pass_data_outof_cfg_layout_mode =
3768 : {
3769 : RTL_PASS, /* type */
3770 : "outof_cfglayout", /* name */
3771 : OPTGROUP_NONE, /* optinfo_flags */
3772 : TV_CFG, /* tv_id */
3773 : 0, /* properties_required */
3774 : 0, /* properties_provided */
3775 : PROP_cfglayout, /* properties_destroyed */
3776 : 0, /* todo_flags_start */
3777 : 0, /* todo_flags_finish */
3778 : };
3779 :
3780 : class pass_outof_cfg_layout_mode : public rtl_opt_pass
3781 : {
3782 : public:
3783 285722 : pass_outof_cfg_layout_mode (gcc::context *ctxt)
3784 571444 : : rtl_opt_pass (pass_data_outof_cfg_layout_mode, ctxt)
3785 : {}
3786 :
3787 : /* opt_pass methods: */
3788 : unsigned int execute (function *) final override;
3789 :
3790 : }; // class pass_outof_cfg_layout_mode
3791 :
3792 : unsigned int
3793 1471360 : pass_outof_cfg_layout_mode::execute (function *fun)
3794 : {
3795 1471360 : basic_block bb;
3796 :
3797 15032846 : FOR_EACH_BB_FN (bb, fun)
3798 13561486 : if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (fun))
3799 12090126 : bb->aux = bb->next_bb;
3800 :
3801 1471360 : cfg_layout_finalize ();
3802 :
3803 1471360 : return 0;
3804 : }
3805 :
3806 : } // anon namespace
3807 :
3808 : rtl_opt_pass *
3809 285722 : make_pass_outof_cfg_layout_mode (gcc::context *ctxt)
3810 : {
3811 285722 : return new pass_outof_cfg_layout_mode (ctxt);
3812 : }
3813 :
3814 :
3815 : /* Link the basic blocks in the correct order, compacting the basic
3816 : block queue while at it. If STAY_IN_CFGLAYOUT_MODE is false, this
3817 : function also clears the basic block header and footer fields.
3818 :
3819 : This function is usually called after a pass (e.g. tracer) finishes
3820 : some transformations while in cfglayout mode. The required sequence
3821 : of the basic blocks is in a linked list along the bb->aux field.
3822 : This functions re-links the basic block prev_bb and next_bb pointers
3823 : accordingly, and it compacts and renumbers the blocks.
3824 :
3825 : FIXME: This currently works only for RTL, but the only RTL-specific
3826 : bits are the STAY_IN_CFGLAYOUT_MODE bits. The tracer pass was moved
3827 : to GIMPLE a long time ago, but it doesn't relink the basic block
3828 : chain. It could do that (to give better initial RTL) if this function
3829 : is made IR-agnostic (and moved to cfganal.cc or cfg.cc while at it). */
3830 :
3831 : void
3832 3148896 : relink_block_chain (bool stay_in_cfglayout_mode)
3833 : {
3834 3148896 : basic_block bb, prev_bb;
3835 3148896 : int index;
3836 :
3837 : /* Maybe dump the re-ordered sequence. */
3838 3148896 : if (dump_file)
3839 : {
3840 168 : fprintf (dump_file, "Reordered sequence:\n");
3841 168 : for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb, index =
3842 : NUM_FIXED_BLOCKS;
3843 1093 : bb;
3844 925 : bb = (basic_block) bb->aux, index++)
3845 : {
3846 925 : fprintf (dump_file, " %i ", index);
3847 925 : if (get_bb_original (bb))
3848 28 : fprintf (dump_file, "duplicate of %i\n",
3849 28 : get_bb_original (bb)->index);
3850 897 : else if (forwarder_block_p (bb)
3851 897 : && !LABEL_P (BB_HEAD (bb)))
3852 16 : fprintf (dump_file, "compensation\n");
3853 : else
3854 881 : fprintf (dump_file, "bb %i\n", bb->index);
3855 : }
3856 : }
3857 :
3858 : /* Now reorder the blocks. */
3859 3148896 : prev_bb = ENTRY_BLOCK_PTR_FOR_FN (cfun);
3860 3148896 : bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb;
3861 38808733 : for (; bb; prev_bb = bb, bb = (basic_block) bb->aux)
3862 : {
3863 35659837 : bb->prev_bb = prev_bb;
3864 35659837 : prev_bb->next_bb = bb;
3865 : }
3866 3148896 : prev_bb->next_bb = EXIT_BLOCK_PTR_FOR_FN (cfun);
3867 3148896 : EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb = prev_bb;
3868 :
3869 : /* Then, clean up the aux fields. */
3870 45106525 : FOR_ALL_BB_FN (bb, cfun)
3871 : {
3872 41957629 : bb->aux = NULL;
3873 41957629 : if (!stay_in_cfglayout_mode)
3874 30082899 : BB_HEADER (bb) = BB_FOOTER (bb) = NULL;
3875 : }
3876 :
3877 : /* Maybe reset the original copy tables, they are not valid anymore
3878 : when we renumber the basic blocks in compact_blocks. If we are
3879 : are going out of cfglayout mode, don't re-allocate the tables. */
3880 3148896 : if (original_copy_tables_initialized_p ())
3881 3148895 : free_original_copy_tables ();
3882 3148896 : if (stay_in_cfglayout_mode)
3883 633539 : initialize_original_copy_tables ();
3884 :
3885 : /* Finally, put basic_block_info in the new order. */
3886 3148896 : compact_blocks ();
3887 3148896 : }
3888 :
3889 :
3890 : /* Given a reorder chain, rearrange the code to match. */
3891 :
3892 : static void
3893 2515357 : fixup_reorder_chain (void)
3894 : {
3895 2515357 : basic_block bb;
3896 2515357 : rtx_insn *insn = NULL;
3897 :
3898 2515357 : if (cfg_layout_function_header)
3899 : {
3900 2515341 : set_first_insn (cfg_layout_function_header);
3901 2515341 : insn = cfg_layout_function_header;
3902 2517976 : while (NEXT_INSN (insn))
3903 : insn = NEXT_INSN (insn);
3904 : }
3905 :
3906 : /* First do the bulk reordering -- rechain the blocks without regard to
3907 : the needed changes to jumps and labels. */
3908 :
3909 26812094 : for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb; bb = (basic_block)
3910 : bb->aux)
3911 : {
3912 24296737 : if (BB_HEADER (bb))
3913 : {
3914 45520 : if (insn)
3915 45520 : SET_NEXT_INSN (insn) = BB_HEADER (bb);
3916 : else
3917 0 : set_first_insn (BB_HEADER (bb));
3918 45520 : SET_PREV_INSN (BB_HEADER (bb)) = insn;
3919 45520 : insn = BB_HEADER (bb);
3920 55572 : while (NEXT_INSN (insn))
3921 : insn = NEXT_INSN (insn);
3922 : }
3923 24296737 : if (insn)
3924 24296721 : SET_NEXT_INSN (insn) = BB_HEAD (bb);
3925 : else
3926 16 : set_first_insn (BB_HEAD (bb));
3927 24296737 : SET_PREV_INSN (BB_HEAD (bb)) = insn;
3928 24296737 : insn = BB_END (bb);
3929 24296737 : if (BB_FOOTER (bb))
3930 : {
3931 2990346 : SET_NEXT_INSN (insn) = BB_FOOTER (bb);
3932 2990346 : SET_PREV_INSN (BB_FOOTER (bb)) = insn;
3933 6032361 : while (NEXT_INSN (insn))
3934 : insn = NEXT_INSN (insn);
3935 : }
3936 : }
3937 :
3938 2515357 : SET_NEXT_INSN (insn) = cfg_layout_function_footer;
3939 2515357 : if (cfg_layout_function_footer)
3940 1019694 : SET_PREV_INSN (cfg_layout_function_footer) = insn;
3941 :
3942 3535850 : while (NEXT_INSN (insn))
3943 : insn = NEXT_INSN (insn);
3944 :
3945 2515357 : set_last_insn (insn);
3946 2515357 : if (flag_checking)
3947 2515319 : verify_insn_chain ();
3948 :
3949 : /* Now add jumps and labels as needed to match the blocks new
3950 : outgoing edges. */
3951 :
3952 2515357 : bool remove_unreachable_blocks = false;
3953 26812094 : for (bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb; bb ; bb = (basic_block)
3954 : bb->aux)
3955 : {
3956 24296737 : edge e_fall, e_taken, e;
3957 24296737 : rtx_insn *bb_end_insn;
3958 24296737 : rtx ret_label = NULL_RTX;
3959 24296737 : basic_block nb;
3960 24296737 : edge_iterator ei;
3961 24296737 : bool asm_goto = false;
3962 :
3963 24296737 : if (EDGE_COUNT (bb->succs) == 0)
3964 20194108 : continue;
3965 :
3966 : /* Find the old fallthru edge, and another non-EH edge for
3967 : a taken jump. */
3968 23025971 : e_taken = e_fall = NULL;
3969 :
3970 58736251 : FOR_EACH_EDGE (e, ei, bb->succs)
3971 35710280 : if (e->flags & EDGE_FALLTHRU)
3972 : e_fall = e;
3973 14402846 : else if (! (e->flags & EDGE_EH))
3974 13140441 : e_taken = e;
3975 :
3976 23025971 : bb_end_insn = BB_END (bb);
3977 23025971 : if (rtx_jump_insn *bb_end_jump = dyn_cast <rtx_jump_insn *> (bb_end_insn))
3978 : {
3979 12707135 : ret_label = JUMP_LABEL (bb_end_jump);
3980 12707135 : if (any_condjump_p (bb_end_jump))
3981 : {
3982 : /* This might happen if the conditional jump has side
3983 : effects and could therefore not be optimized away.
3984 : Make the basic block to end with a barrier in order
3985 : to prevent rtl_verify_flow_info from complaining. */
3986 11348923 : if (!e_fall)
3987 : {
3988 0 : gcc_assert (!onlyjump_p (bb_end_jump)
3989 : || returnjump_p (bb_end_jump)
3990 : || (e_taken->flags & EDGE_CROSSING));
3991 0 : emit_barrier_after (bb_end_jump);
3992 0 : continue;
3993 : }
3994 :
3995 : /* If the old fallthru is still next, nothing to do. */
3996 11348923 : if (bb->aux == e_fall->dest
3997 2734718 : || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
3998 8614217 : continue;
3999 :
4000 : /* The degenerated case of conditional jump jumping to the next
4001 : instruction can happen for jumps with side effects. We need
4002 : to construct a forwarder block and this will be done just
4003 : fine by force_nonfallthru below. */
4004 2734706 : if (!e_taken)
4005 : ;
4006 :
4007 : /* There is another special case: if *neither* block is next,
4008 : such as happens at the very end of a function, then we'll
4009 : need to add a new unconditional jump. Choose the taken
4010 : edge based on known or assumed probability. */
4011 2734706 : else if (bb->aux != e_taken->dest)
4012 : {
4013 578733 : rtx note = find_reg_note (bb_end_jump, REG_BR_PROB, 0);
4014 :
4015 578733 : if (note
4016 : && profile_probability::from_reg_br_prob_note
4017 557205 : (XINT (note, 0)) < profile_probability::even ()
4018 774276 : && invert_jump (bb_end_jump,
4019 195543 : (e_fall->dest
4020 195543 : == EXIT_BLOCK_PTR_FOR_FN (cfun)
4021 : ? NULL_RTX
4022 195543 : : label_for_bb (e_fall->dest)), 0))
4023 : {
4024 195543 : e_fall->flags &= ~EDGE_FALLTHRU;
4025 195543 : gcc_checking_assert (could_fall_through
4026 : (e_taken->src, e_taken->dest));
4027 195543 : e_taken->flags |= EDGE_FALLTHRU;
4028 195543 : update_br_prob_note (bb);
4029 195543 : e = e_fall, e_fall = e_taken, e_taken = e;
4030 : }
4031 : }
4032 :
4033 : /* If the "jumping" edge is a crossing edge, and the fall
4034 : through edge is non-crossing, leave things as they are. */
4035 2155973 : else if ((e_taken->flags & EDGE_CROSSING)
4036 70721 : && !(e_fall->flags & EDGE_CROSSING))
4037 70721 : continue;
4038 :
4039 : /* Otherwise we can try to invert the jump. This will
4040 : basically never fail, however, keep up the pretense. */
4041 2085252 : else if (invert_jump (bb_end_jump,
4042 : (e_fall->dest
4043 : == EXIT_BLOCK_PTR_FOR_FN (cfun)
4044 : ? NULL_RTX
4045 2085252 : : label_for_bb (e_fall->dest)), 0))
4046 : {
4047 2085252 : e_fall->flags &= ~EDGE_FALLTHRU;
4048 2085252 : gcc_checking_assert (could_fall_through
4049 : (e_taken->src, e_taken->dest));
4050 2085252 : e_taken->flags |= EDGE_FALLTHRU;
4051 2085252 : update_br_prob_note (bb);
4052 2085252 : if (LABEL_NUSES (ret_label) == 0
4053 2085252 : && single_pred_p (e_taken->dest))
4054 1292563 : delete_insn (as_a<rtx_insn *> (ret_label));
4055 2085252 : continue;
4056 : }
4057 : }
4058 1358212 : else if (extract_asm_operands (PATTERN (bb_end_insn)) != NULL)
4059 : {
4060 : /* If the old fallthru is still next or if
4061 : asm goto doesn't have a fallthru (e.g. when followed by
4062 : __builtin_unreachable ()), nothing to do. */
4063 1081 : if (! e_fall
4064 1015 : || bb->aux == e_fall->dest
4065 101 : || e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
4066 980 : continue;
4067 :
4068 : /* Otherwise we'll have to use the fallthru fixup below.
4069 : But avoid redirecting asm goto to EXIT. */
4070 : asm_goto = true;
4071 : }
4072 : else
4073 : {
4074 : /* Otherwise we have some return, switch or computed
4075 : jump. In the 99% case, there should not have been a
4076 : fallthru edge. */
4077 1357131 : gcc_assert (returnjump_p (bb_end_insn) || !e_fall);
4078 1357131 : continue;
4079 : }
4080 : }
4081 : else
4082 : {
4083 : /* No fallthru implies a noreturn function with EH edges, or
4084 : something similarly bizarre. In any case, we don't need to
4085 : do anything. */
4086 10318836 : if (! e_fall)
4087 361340 : continue;
4088 :
4089 : /* If the fallthru block is still next, nothing to do. */
4090 9957496 : if (bb->aux == e_fall->dest)
4091 5067111 : continue;
4092 :
4093 : /* A fallthru to exit block. */
4094 4890385 : if (e_fall->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
4095 1366590 : continue;
4096 : }
4097 :
4098 : /* If E_FALL->dest is just a return block, then we can emit a
4099 : return rather than a jump to the return block. */
4100 578733 : rtx_insn *ret, *use;
4101 578733 : basic_block dest;
4102 578733 : if (!asm_goto
4103 4102528 : && bb_is_just_return (e_fall->dest, &ret, &use)
4104 736 : && ((PATTERN (ret) == simple_return_rtx && targetm.have_simple_return ())
4105 0 : || (PATTERN (ret) == ret_rtx && targetm.have_return ())))
4106 : {
4107 736 : ret_label = PATTERN (ret);
4108 736 : dest = EXIT_BLOCK_PTR_FOR_FN (cfun);
4109 :
4110 736 : e_fall->flags &= ~EDGE_CROSSING;
4111 : /* E_FALL->dest might become unreachable as a result of
4112 : replacing the jump with a return. So arrange to remove
4113 : unreachable blocks. */
4114 736 : remove_unreachable_blocks = true;
4115 : }
4116 : else
4117 : {
4118 4101893 : dest = e_fall->dest;
4119 : }
4120 :
4121 : /* We got here if we need to add a new jump insn.
4122 : Note force_nonfallthru can delete E_FALL and thus we have to
4123 : save E_FALL->src prior to the call to force_nonfallthru. */
4124 4102629 : nb = force_nonfallthru_and_redirect (e_fall, dest, ret_label);
4125 4102629 : if (nb)
4126 : {
4127 755448 : nb->aux = bb->aux;
4128 755448 : bb->aux = nb;
4129 : /* Don't process this new block. */
4130 755448 : bb = nb;
4131 : }
4132 : }
4133 :
4134 2515357 : relink_block_chain (/*stay_in_cfglayout_mode=*/false);
4135 :
4136 : /* Annoying special case - jump around dead jumptables left in the code. */
4137 27638263 : FOR_EACH_BB_FN (bb, cfun)
4138 : {
4139 25122906 : edge e = find_fallthru_edge (bb->succs);
4140 :
4141 25122906 : if (e && !can_fallthru (e->src, e->dest))
4142 70721 : force_nonfallthru (e);
4143 : }
4144 :
4145 : /* Ensure goto_locus from edges has some instructions with that locus in RTL
4146 : when not optimizing. */
4147 2515357 : if (!optimize && !DECL_IGNORED_P (current_function_decl))
4148 3818019 : FOR_EACH_BB_FN (bb, cfun)
4149 : {
4150 3392249 : edge e;
4151 3392249 : edge_iterator ei;
4152 :
4153 8070711 : FOR_EACH_EDGE (e, ei, bb->succs)
4154 4678462 : if (LOCATION_LOCUS (e->goto_locus) != UNKNOWN_LOCATION
4155 4678462 : && !(e->flags & EDGE_ABNORMAL))
4156 : {
4157 722728 : edge e2;
4158 722728 : edge_iterator ei2;
4159 722728 : basic_block dest, nb;
4160 722728 : rtx_insn *end;
4161 :
4162 722728 : insn = BB_END (e->src);
4163 722728 : end = PREV_INSN (BB_HEAD (e->src));
4164 722728 : while (insn != end
4165 867662 : && (!NONDEBUG_INSN_P (insn) || !INSN_HAS_LOCATION (insn)))
4166 144934 : insn = PREV_INSN (insn);
4167 1229580 : if (insn != end
4168 722728 : && loc_equal (INSN_LOCATION (insn), e->goto_locus))
4169 521266 : continue;
4170 215876 : if (simplejump_p (BB_END (e->src))
4171 215876 : && !INSN_HAS_LOCATION (BB_END (e->src)))
4172 : {
4173 0 : INSN_LOCATION (BB_END (e->src)) = e->goto_locus;
4174 0 : continue;
4175 : }
4176 215876 : dest = e->dest;
4177 215876 : if (dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
4178 : {
4179 : /* Non-fallthru edges to the exit block cannot be split. */
4180 143616 : if (!(e->flags & EDGE_FALLTHRU))
4181 0 : continue;
4182 : }
4183 : else
4184 : {
4185 72260 : insn = BB_HEAD (dest);
4186 72260 : end = NEXT_INSN (BB_END (dest));
4187 284659 : while (insn != end && !NONDEBUG_INSN_P (insn))
4188 140139 : insn = NEXT_INSN (insn);
4189 44467 : if (insn != end && INSN_HAS_LOCATION (insn)
4190 114677 : && loc_equal (INSN_LOCATION (insn), e->goto_locus))
4191 14414 : continue;
4192 : }
4193 201462 : nb = split_edge (e);
4194 201462 : if (!INSN_P (BB_END (nb)))
4195 201462 : BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb),
4196 : nb);
4197 201462 : INSN_LOCATION (BB_END (nb)) = e->goto_locus;
4198 :
4199 : /* If there are other incoming edges to the destination block
4200 : with the same goto locus, redirect them to the new block as
4201 : well, this can prevent other such blocks from being created
4202 : in subsequent iterations of the loop. */
4203 467290 : for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); )
4204 265828 : if (LOCATION_LOCUS (e2->goto_locus) != UNKNOWN_LOCATION
4205 43299 : && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU))
4206 309127 : && e->goto_locus == e2->goto_locus)
4207 15463 : redirect_edge_and_branch (e2, nb);
4208 : else
4209 250365 : ei_next (&ei2);
4210 : }
4211 : }
4212 :
4213 : /* Replacing a jump with a return may have exposed an unreachable
4214 : block. Conditionally remove them if such transformations were
4215 : made. */
4216 2515357 : if (remove_unreachable_blocks)
4217 726 : delete_unreachable_blocks ();
4218 2515357 : }
4219 :
4220 : /* Perform sanity checks on the insn chain.
4221 : 1. Check that next/prev pointers are consistent in both the forward and
4222 : reverse direction.
4223 : 2. Count insns in chain, going both directions, and check if equal.
4224 : 3. Check that get_last_insn () returns the actual end of chain. */
4225 :
4226 : DEBUG_FUNCTION void
4227 5030638 : verify_insn_chain (void)
4228 : {
4229 5030638 : rtx_insn *x, *prevx, *nextx;
4230 5030638 : int insn_cnt1, insn_cnt2;
4231 :
4232 5030638 : for (prevx = NULL, insn_cnt1 = 1, x = get_insns ();
4233 609011349 : x != 0;
4234 603980711 : prevx = x, insn_cnt1++, x = NEXT_INSN (x))
4235 603980711 : gcc_assert (PREV_INSN (x) == prevx);
4236 :
4237 5030638 : gcc_assert (prevx == get_last_insn ());
4238 :
4239 : for (nextx = NULL, insn_cnt2 = 1, x = get_last_insn ();
4240 609011349 : x != 0;
4241 603980711 : nextx = x, insn_cnt2++, x = PREV_INSN (x))
4242 603980711 : gcc_assert (NEXT_INSN (x) == nextx);
4243 :
4244 5030638 : gcc_assert (insn_cnt1 == insn_cnt2);
4245 5030638 : }
4246 :
4247 : /* If we have assembler epilogues, the block falling through to exit must
4248 : be the last one in the reordered chain when we reach final. Ensure
4249 : that this condition is met. */
4250 : static void
4251 0 : fixup_fallthru_exit_predecessor (void)
4252 : {
4253 0 : edge e;
4254 0 : basic_block bb = NULL;
4255 :
4256 : /* This transformation is not valid before reload, because we might
4257 : separate a call from the instruction that copies the return
4258 : value. */
4259 0 : gcc_assert (reload_completed);
4260 :
4261 0 : e = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
4262 0 : if (e)
4263 0 : bb = e->src;
4264 :
4265 0 : if (bb && bb->aux)
4266 : {
4267 0 : basic_block c = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb;
4268 :
4269 : /* If the very first block is the one with the fall-through exit
4270 : edge, we have to split that block. */
4271 0 : if (c == bb)
4272 : {
4273 0 : bb = split_block_after_labels (bb)->dest;
4274 0 : bb->aux = c->aux;
4275 0 : c->aux = bb;
4276 0 : BB_FOOTER (bb) = BB_FOOTER (c);
4277 0 : BB_FOOTER (c) = NULL;
4278 : }
4279 :
4280 0 : while (c->aux != bb)
4281 : c = (basic_block) c->aux;
4282 :
4283 0 : c->aux = bb->aux;
4284 0 : while (c->aux)
4285 : c = (basic_block) c->aux;
4286 :
4287 0 : c->aux = bb;
4288 0 : bb->aux = NULL;
4289 : }
4290 0 : }
4291 :
4292 : /* In case there are more than one fallthru predecessors of exit, force that
4293 : there is only one. */
4294 :
4295 : static void
4296 2515357 : force_one_exit_fallthru (void)
4297 : {
4298 2515357 : edge e, predecessor = NULL;
4299 2515357 : bool more = false;
4300 2515357 : edge_iterator ei;
4301 2515357 : basic_block forwarder, bb;
4302 :
4303 5322976 : FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
4304 2807620 : if (e->flags & EDGE_FALLTHRU)
4305 : {
4306 1366603 : if (predecessor == NULL)
4307 : predecessor = e;
4308 : else
4309 : {
4310 : more = true;
4311 : break;
4312 : }
4313 : }
4314 :
4315 2515357 : if (!more)
4316 2515356 : return;
4317 :
4318 : /* Exit has several fallthru predecessors. Create a forwarder block for
4319 : them. */
4320 1 : forwarder = split_edge (predecessor);
4321 1 : for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
4322 3 : (e = ei_safe_edge (ei)); )
4323 : {
4324 2 : if (e->src == forwarder
4325 1 : || !(e->flags & EDGE_FALLTHRU))
4326 1 : ei_next (&ei);
4327 : else
4328 1 : redirect_edge_and_branch_force (e, forwarder);
4329 : }
4330 :
4331 : /* Fix up the chain of blocks -- make FORWARDER immediately precede the
4332 : exit block. */
4333 5 : FOR_EACH_BB_FN (bb, cfun)
4334 : {
4335 5 : if (bb->aux == NULL && bb != forwarder)
4336 : {
4337 1 : bb->aux = forwarder;
4338 1 : break;
4339 : }
4340 : }
4341 : }
4342 :
4343 : /* Return true in case it is possible to duplicate the basic block BB. */
4344 :
4345 : static bool
4346 8340883 : cfg_layout_can_duplicate_bb_p (const_basic_block bb)
4347 : {
4348 : /* Do not attempt to duplicate tablejumps, as we need to unshare
4349 : the dispatch table. This is difficult to do, as the instructions
4350 : computing jump destination may be hoisted outside the basic block. */
4351 8340883 : if (tablejump_p (BB_END (bb), NULL, NULL))
4352 : return false;
4353 :
4354 : /* Do not duplicate blocks containing insns that can't be copied. */
4355 8338064 : if (targetm.cannot_copy_insn_p)
4356 : {
4357 0 : rtx_insn *insn = BB_HEAD (bb);
4358 0 : while (1)
4359 : {
4360 0 : if (INSN_P (insn) && targetm.cannot_copy_insn_p (insn))
4361 : return false;
4362 0 : if (insn == BB_END (bb))
4363 : break;
4364 0 : insn = NEXT_INSN (insn);
4365 : }
4366 : }
4367 :
4368 : return true;
4369 : }
4370 :
4371 : rtx_insn *
4372 887860 : duplicate_insn_chain (rtx_insn *from, rtx_insn *to,
4373 : class loop *loop, copy_bb_data *id)
4374 : {
4375 887860 : rtx_insn *insn, *next, *copy;
4376 887860 : rtx_note *last;
4377 :
4378 : /* Avoid updating of boundaries of previous basic block. The
4379 : note will get removed from insn stream in fixup. */
4380 887860 : last = emit_note (NOTE_INSN_DELETED);
4381 :
4382 : /* Create copy at the end of INSN chain. The chain will
4383 : be reordered later. */
4384 6291210 : for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn))
4385 : {
4386 5403350 : switch (GET_CODE (insn))
4387 : {
4388 1440795 : case DEBUG_INSN:
4389 : /* Don't duplicate label debug insns. */
4390 1440795 : if (DEBUG_BIND_INSN_P (insn)
4391 1108341 : && TREE_CODE (INSN_VAR_LOCATION_DECL (insn)) == LABEL_DECL)
4392 : break;
4393 : /* FALLTHRU */
4394 3657587 : case INSN:
4395 3657587 : case CALL_INSN:
4396 3657587 : case JUMP_INSN:
4397 3657587 : copy = emit_copy_of_insn_after (insn, get_last_insn ());
4398 3657587 : if (JUMP_P (insn) && JUMP_LABEL (insn) != NULL_RTX
4399 484462 : && ANY_RETURN_P (JUMP_LABEL (insn)))
4400 178998 : JUMP_LABEL (copy) = JUMP_LABEL (insn);
4401 3657587 : maybe_copy_prologue_epilogue_insn (insn, copy);
4402 : /* If requested remap dependence info of cliques brought in
4403 : via inlining. */
4404 3657587 : if (id)
4405 : {
4406 1999576 : subrtx_iterator::array_type array;
4407 12051229 : FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
4408 10065684 : if (MEM_P (*iter) && MEM_EXPR (*iter))
4409 : {
4410 320660 : tree op = MEM_EXPR (*iter);
4411 320660 : if (TREE_CODE (op) == WITH_SIZE_EXPR)
4412 0 : op = TREE_OPERAND (op, 0);
4413 355295 : while (handled_component_p (op))
4414 34635 : op = TREE_OPERAND (op, 0);
4415 320660 : if ((TREE_CODE (op) == MEM_REF
4416 320660 : || TREE_CODE (op) == TARGET_MEM_REF)
4417 301786 : && MR_DEPENDENCE_CLIQUE (op) > 1
4418 335271 : && (!loop
4419 14611 : || (MR_DEPENDENCE_CLIQUE (op)
4420 14611 : != loop->owned_clique)))
4421 : {
4422 1855 : if (!id->dependence_map)
4423 944 : id->dependence_map = new hash_map<dependence_hash,
4424 : unsigned short>;
4425 1855 : bool existed;
4426 1855 : unsigned short &newc = id->dependence_map->get_or_insert
4427 1855 : (MR_DEPENDENCE_CLIQUE (op), &existed);
4428 1855 : if (!existed)
4429 : {
4430 956 : gcc_assert
4431 : (MR_DEPENDENCE_CLIQUE (op) <= cfun->last_clique);
4432 1912 : newc = get_new_clique (cfun);
4433 : }
4434 : /* We cannot adjust MR_DEPENDENCE_CLIQUE in-place
4435 : since MEM_EXPR is shared so make a copy and
4436 : walk to the subtree again. */
4437 1855 : tree new_expr = unshare_expr (MEM_EXPR (*iter));
4438 1855 : tree orig_new_expr = new_expr;
4439 1855 : if (TREE_CODE (new_expr) == WITH_SIZE_EXPR)
4440 0 : new_expr = TREE_OPERAND (new_expr, 0);
4441 2422 : while (handled_component_p (new_expr))
4442 567 : new_expr = TREE_OPERAND (new_expr, 0);
4443 1855 : MR_DEPENDENCE_CLIQUE (new_expr) = newc;
4444 1855 : set_mem_expr (const_cast <rtx> (*iter), orig_new_expr);
4445 : }
4446 : }
4447 1999576 : }
4448 : break;
4449 :
4450 0 : case JUMP_TABLE_DATA:
4451 : /* Avoid copying of dispatch tables. We never duplicate
4452 : tablejumps, so this can hit only in case the table got
4453 : moved far from original jump.
4454 : Avoid copying following barrier as well if any
4455 : (and debug insns in between). */
4456 0 : for (next = NEXT_INSN (insn);
4457 0 : next != NEXT_INSN (to);
4458 0 : next = NEXT_INSN (next))
4459 0 : if (!DEBUG_INSN_P (next))
4460 : break;
4461 0 : if (next != NEXT_INSN (to) && BARRIER_P (next))
4462 5403350 : insn = next;
4463 : break;
4464 :
4465 : case CODE_LABEL:
4466 : break;
4467 :
4468 180442 : case BARRIER:
4469 180442 : emit_barrier ();
4470 180442 : break;
4471 :
4472 920379 : case NOTE:
4473 920379 : switch (NOTE_KIND (insn))
4474 : {
4475 : /* In case prologue is empty and function contain label
4476 : in first BB, we may want to copy the block. */
4477 : case NOTE_INSN_PROLOGUE_END:
4478 :
4479 : case NOTE_INSN_DELETED:
4480 : case NOTE_INSN_DELETED_LABEL:
4481 : case NOTE_INSN_DELETED_DEBUG_LABEL:
4482 : /* No problem to strip these. */
4483 : case NOTE_INSN_FUNCTION_BEG:
4484 : /* There is always just single entry to function. */
4485 : case NOTE_INSN_BASIC_BLOCK:
4486 : /* We should only switch text sections once. */
4487 : case NOTE_INSN_SWITCH_TEXT_SECTIONS:
4488 : break;
4489 :
4490 176484 : case NOTE_INSN_EPILOGUE_BEG:
4491 176484 : case NOTE_INSN_UPDATE_SJLJ_CONTEXT:
4492 176484 : emit_note_copy (as_a <rtx_note *> (insn));
4493 176484 : break;
4494 :
4495 0 : default:
4496 : /* All other notes should have already been eliminated. */
4497 0 : gcc_unreachable ();
4498 : }
4499 : break;
4500 0 : default:
4501 0 : gcc_unreachable ();
4502 : }
4503 : }
4504 887860 : insn = NEXT_INSN (last);
4505 887860 : delete_insn (last);
4506 887860 : return insn;
4507 : }
4508 :
4509 : /* Create a duplicate of the basic block BB. */
4510 :
4511 : static basic_block
4512 704426 : cfg_layout_duplicate_bb (basic_block bb, copy_bb_data *id)
4513 : {
4514 704426 : rtx_insn *insn;
4515 704426 : basic_block new_bb;
4516 :
4517 704426 : class loop *loop = (id && current_loops) ? bb->loop_father : NULL;
4518 :
4519 704426 : insn = duplicate_insn_chain (BB_HEAD (bb), BB_END (bb), loop, id);
4520 704426 : new_bb = create_basic_block (insn,
4521 : insn ? get_last_insn () : NULL,
4522 704426 : EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb);
4523 :
4524 704426 : BB_COPY_PARTITION (new_bb, bb);
4525 704426 : if (BB_HEADER (bb))
4526 : {
4527 : insn = BB_HEADER (bb);
4528 3673 : while (NEXT_INSN (insn))
4529 : insn = NEXT_INSN (insn);
4530 2829 : insn = duplicate_insn_chain (BB_HEADER (bb), insn, loop, id);
4531 2829 : if (insn)
4532 0 : BB_HEADER (new_bb) = unlink_insn_chain (insn, get_last_insn ());
4533 : }
4534 :
4535 704426 : if (BB_FOOTER (bb))
4536 : {
4537 : insn = BB_FOOTER (bb);
4538 180519 : while (NEXT_INSN (insn))
4539 : insn = NEXT_INSN (insn);
4540 180396 : insn = duplicate_insn_chain (BB_FOOTER (bb), insn, loop, id);
4541 180396 : if (insn)
4542 180395 : BB_FOOTER (new_bb) = unlink_insn_chain (insn, get_last_insn ());
4543 : }
4544 :
4545 704426 : return new_bb;
4546 : }
4547 :
4548 :
4549 : /* Main entry point to this module - initialize the datastructures for
4550 : CFG layout changes. It keeps LOOPS up-to-date if not null.
4551 :
4552 : FLAGS is a set of additional flags to pass to cleanup_cfg(). */
4553 :
4554 : void
4555 2515356 : cfg_layout_initialize (int flags)
4556 : {
4557 2515356 : rtx_insn_list *x;
4558 2515356 : basic_block bb;
4559 :
4560 : /* Once bb partitioning is complete, cfg layout mode should not be
4561 : re-entered. Entering cfg layout mode may require fixups. As an
4562 : example, if edge forwarding performed when optimizing the cfg
4563 : layout required moving a block from the hot to the cold
4564 : section. This would create an illegal partitioning unless some
4565 : manual fixup was performed. */
4566 2515356 : gcc_assert (!crtl->bb_reorder_complete || !crtl->has_bb_partition);
4567 :
4568 2515356 : initialize_original_copy_tables ();
4569 :
4570 2515356 : cfg_layout_rtl_register_cfg_hooks ();
4571 :
4572 2515356 : record_effective_endpoints ();
4573 :
4574 : /* Make sure that the targets of non local gotos are marked. */
4575 2517733 : for (x = nonlocal_goto_handler_labels; x; x = x->next ())
4576 : {
4577 2377 : bb = BLOCK_FOR_INSN (x->insn ());
4578 2377 : bb->flags |= BB_NON_LOCAL_GOTO_TARGET;
4579 : }
4580 :
4581 2515356 : cleanup_cfg (CLEANUP_CFGLAYOUT | flags);
4582 2515356 : }
4583 :
4584 : /* Splits superblocks. */
4585 : void
4586 62307 : break_superblocks (void)
4587 : {
4588 62307 : bool need = false;
4589 62307 : basic_block bb;
4590 :
4591 62307 : auto_sbitmap superblocks (last_basic_block_for_fn (cfun));
4592 62307 : bitmap_clear (superblocks);
4593 :
4594 3637497 : FOR_EACH_BB_FN (bb, cfun)
4595 3575190 : if (bb->flags & BB_SUPERBLOCK)
4596 : {
4597 204366 : bb->flags &= ~BB_SUPERBLOCK;
4598 204366 : bitmap_set_bit (superblocks, bb->index);
4599 204366 : need = true;
4600 : }
4601 :
4602 62307 : if (need)
4603 : {
4604 53066 : rebuild_jump_labels (get_insns ());
4605 53066 : find_many_sub_basic_blocks (superblocks);
4606 : }
4607 62307 : }
4608 :
4609 : /* Finalize the changes: reorder insn list according to the sequence specified
4610 : by aux pointers, enter compensation code, rebuild scope forest. */
4611 :
4612 : void
4613 2515357 : cfg_layout_finalize (void)
4614 : {
4615 2515357 : free_dominance_info (CDI_DOMINATORS);
4616 2515357 : force_one_exit_fallthru ();
4617 2515357 : rtl_register_cfg_hooks ();
4618 2515357 : if (reload_completed && !targetm.have_epilogue ())
4619 0 : fixup_fallthru_exit_predecessor ();
4620 2515357 : fixup_reorder_chain ();
4621 :
4622 2515357 : rebuild_jump_labels (get_insns ());
4623 2515357 : delete_dead_jumptables ();
4624 :
4625 2515357 : if (flag_checking)
4626 2515319 : verify_insn_chain ();
4627 2515357 : checking_verify_flow_info ();
4628 2515357 : }
4629 :
4630 :
4631 : /* Same as split_block but update cfg_layout structures. */
4632 :
4633 : static basic_block
4634 17666 : cfg_layout_split_block (basic_block bb, void *insnp)
4635 : {
4636 17666 : rtx insn = (rtx) insnp;
4637 17666 : basic_block new_bb = rtl_split_block (bb, insn);
4638 :
4639 17666 : BB_FOOTER (new_bb) = BB_FOOTER (bb);
4640 17666 : BB_FOOTER (bb) = NULL;
4641 :
4642 17666 : return new_bb;
4643 : }
4644 :
4645 : /* Redirect Edge to DEST. */
4646 : static edge
4647 10107353 : cfg_layout_redirect_edge_and_branch (edge e, basic_block dest)
4648 : {
4649 10107353 : basic_block src = e->src;
4650 10107353 : edge ret;
4651 :
4652 10107353 : if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
4653 : return NULL;
4654 :
4655 10107353 : if (e->dest == dest)
4656 : return e;
4657 :
4658 10107353 : if (e->flags & EDGE_CROSSING
4659 7 : && BB_PARTITION (e->src) == BB_PARTITION (dest)
4660 10107355 : && simplejump_p (BB_END (src)))
4661 : {
4662 1 : if (dump_file)
4663 0 : fprintf (dump_file,
4664 : "Removing crossing jump while redirecting edge form %i to %i\n",
4665 0 : e->src->index, dest->index);
4666 1 : delete_insn (BB_END (src));
4667 1 : remove_barriers_from_footer (src);
4668 1 : e->flags |= EDGE_FALLTHRU;
4669 : }
4670 :
4671 10107353 : if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
4672 10107353 : && (ret = try_redirect_by_replacing_jump (e, dest, true)))
4673 : {
4674 303349 : df_set_bb_dirty (src);
4675 303349 : return ret;
4676 : }
4677 :
4678 9804004 : if (e->src == ENTRY_BLOCK_PTR_FOR_FN (cfun)
4679 0 : && (e->flags & EDGE_FALLTHRU) && !(e->flags & EDGE_COMPLEX))
4680 : {
4681 0 : if (dump_file)
4682 0 : fprintf (dump_file, "Redirecting entry edge from bb %i to %i\n",
4683 : e->src->index, dest->index);
4684 :
4685 0 : df_set_bb_dirty (e->src);
4686 0 : redirect_edge_succ (e, dest);
4687 0 : return e;
4688 : }
4689 :
4690 : /* Redirect_edge_and_branch may decide to turn branch into fallthru edge
4691 : in the case the basic block appears to be in sequence. Avoid this
4692 : transformation. */
4693 :
4694 9804004 : if (e->flags & EDGE_FALLTHRU)
4695 : {
4696 : /* Redirect any branch edges unified with the fallthru one. */
4697 4692945 : if (JUMP_P (BB_END (src))
4698 4692945 : && label_is_jump_target_p (BB_HEAD (e->dest),
4699 : BB_END (src)))
4700 : {
4701 170 : edge redirected;
4702 :
4703 170 : if (dump_file)
4704 0 : fprintf (dump_file, "Fallthru edge unified with branch "
4705 : "%i->%i redirected to %i\n",
4706 0 : e->src->index, e->dest->index, dest->index);
4707 170 : e->flags &= ~EDGE_FALLTHRU;
4708 170 : redirected = redirect_branch_edge (e, dest);
4709 170 : gcc_assert (redirected);
4710 170 : redirected->flags |= EDGE_FALLTHRU;
4711 170 : df_set_bb_dirty (redirected->src);
4712 170 : return redirected;
4713 : }
4714 : /* In case we are redirecting fallthru edge to the branch edge
4715 : of conditional jump, remove it. */
4716 4692775 : if (EDGE_COUNT (src->succs) == 2)
4717 : {
4718 : /* Find the edge that is different from E. */
4719 3633238 : edge s = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e);
4720 :
4721 3633238 : if (s->dest == dest
4722 2 : && any_condjump_p (BB_END (src))
4723 3633238 : && onlyjump_p (BB_END (src)))
4724 0 : delete_insn (BB_END (src));
4725 : }
4726 4692775 : if (dump_file)
4727 2201 : fprintf (dump_file, "Redirecting fallthru edge %i->%i to %i\n",
4728 2201 : e->src->index, e->dest->index, dest->index);
4729 4692775 : ret = redirect_edge_succ_nodup (e, dest);
4730 : }
4731 : else
4732 5111059 : ret = redirect_branch_edge (e, dest);
4733 :
4734 9803834 : if (!ret)
4735 : return NULL;
4736 :
4737 9803834 : fixup_partition_crossing (ret);
4738 : /* We don't want simplejumps in the insn stream during cfglayout. */
4739 9803834 : gcc_assert (!simplejump_p (BB_END (src)) || CROSSING_JUMP_P (BB_END (src)));
4740 :
4741 9803834 : df_set_bb_dirty (src);
4742 9803834 : return ret;
4743 : }
4744 :
4745 : /* Simple wrapper as we always can redirect fallthru edges. */
4746 : static basic_block
4747 4812321 : cfg_layout_redirect_edge_and_branch_force (edge e, basic_block dest)
4748 : {
4749 4812321 : edge redirected = cfg_layout_redirect_edge_and_branch (e, dest);
4750 :
4751 4812321 : gcc_assert (redirected);
4752 4812321 : return NULL;
4753 : }
4754 :
4755 : /* Same as delete_basic_block but update cfg_layout structures. */
4756 :
4757 : static void
4758 5560261 : cfg_layout_delete_block (basic_block bb)
4759 : {
4760 5560261 : rtx_insn *insn, *next, *prev = PREV_INSN (BB_HEAD (bb)), *remaints;
4761 5560261 : rtx_insn **to;
4762 :
4763 5560261 : if (BB_HEADER (bb))
4764 : {
4765 76 : next = BB_HEAD (bb);
4766 76 : if (prev)
4767 76 : SET_NEXT_INSN (prev) = BB_HEADER (bb);
4768 : else
4769 0 : set_first_insn (BB_HEADER (bb));
4770 76 : SET_PREV_INSN (BB_HEADER (bb)) = prev;
4771 76 : insn = BB_HEADER (bb);
4772 77 : while (NEXT_INSN (insn))
4773 : insn = NEXT_INSN (insn);
4774 76 : SET_NEXT_INSN (insn) = next;
4775 76 : SET_PREV_INSN (next) = insn;
4776 : }
4777 5560261 : next = NEXT_INSN (BB_END (bb));
4778 5560261 : if (BB_FOOTER (bb))
4779 : {
4780 : insn = BB_FOOTER (bb);
4781 2847607 : while (insn)
4782 : {
4783 1423807 : if (BARRIER_P (insn))
4784 : {
4785 1423793 : if (PREV_INSN (insn))
4786 3 : SET_NEXT_INSN (PREV_INSN (insn)) = NEXT_INSN (insn);
4787 : else
4788 1423790 : BB_FOOTER (bb) = NEXT_INSN (insn);
4789 1423793 : if (NEXT_INSN (insn))
4790 4 : SET_PREV_INSN (NEXT_INSN (insn)) = PREV_INSN (insn);
4791 : }
4792 1423807 : if (LABEL_P (insn))
4793 : break;
4794 1423806 : insn = NEXT_INSN (insn);
4795 : }
4796 1423801 : if (BB_FOOTER (bb))
4797 : {
4798 14 : insn = BB_END (bb);
4799 14 : SET_NEXT_INSN (insn) = BB_FOOTER (bb);
4800 14 : SET_PREV_INSN (BB_FOOTER (bb)) = insn;
4801 30 : while (NEXT_INSN (insn))
4802 : insn = NEXT_INSN (insn);
4803 14 : SET_NEXT_INSN (insn) = next;
4804 14 : if (next)
4805 12 : SET_PREV_INSN (next) = insn;
4806 : else
4807 2 : set_last_insn (insn);
4808 : }
4809 : }
4810 5560261 : if (bb->next_bb != EXIT_BLOCK_PTR_FOR_FN (cfun))
4811 5526432 : to = &BB_HEADER (bb->next_bb);
4812 : else
4813 : to = &cfg_layout_function_footer;
4814 :
4815 5560261 : rtl_delete_block (bb);
4816 :
4817 5560261 : if (prev)
4818 5560261 : prev = NEXT_INSN (prev);
4819 : else
4820 0 : prev = get_insns ();
4821 5560261 : if (next)
4822 5526429 : next = PREV_INSN (next);
4823 : else
4824 33832 : next = get_last_insn ();
4825 :
4826 11120522 : if (next && NEXT_INSN (next) != prev)
4827 : {
4828 2705 : remaints = unlink_insn_chain (prev, next);
4829 2705 : insn = remaints;
4830 5669 : while (NEXT_INSN (insn))
4831 : insn = NEXT_INSN (insn);
4832 2705 : SET_NEXT_INSN (insn) = *to;
4833 2705 : if (*to)
4834 702 : SET_PREV_INSN (*to) = insn;
4835 2705 : *to = remaints;
4836 : }
4837 5560261 : }
4838 :
4839 : /* Return true when blocks A and B can be safely merged. */
4840 :
4841 : static bool
4842 3102849 : cfg_layout_can_merge_blocks_p (basic_block a, basic_block b)
4843 : {
4844 : /* If we are partitioning hot/cold basic blocks, we don't want to
4845 : mess up unconditional or indirect jumps that cross between hot
4846 : and cold sections.
4847 :
4848 : Basic block partitioning may result in some jumps that appear to
4849 : be optimizable (or blocks that appear to be mergeable), but which really
4850 : must be left untouched (they are required to make it safely across
4851 : partition boundaries). See the comments at the top of
4852 : bb-reorder.cc:partition_hot_cold_basic_blocks for complete details. */
4853 :
4854 3102849 : if (BB_PARTITION (a) != BB_PARTITION (b))
4855 : return false;
4856 :
4857 : /* Protect the loop latches. */
4858 2936737 : if (current_loops && b->loop_father->latch == b)
4859 : return false;
4860 :
4861 : /* If we would end up moving B's instructions, make sure it doesn't fall
4862 : through into the exit block, since we cannot recover from a fallthrough
4863 : edge into the exit block occurring in the middle of a function. */
4864 2554982 : if (NEXT_INSN (BB_END (a)) != BB_HEAD (b))
4865 : {
4866 1605408 : edge e = find_fallthru_edge (b->succs);
4867 1605408 : if (e && e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
4868 : return false;
4869 : }
4870 :
4871 : /* There must be exactly one edge in between the blocks. */
4872 1847695 : return (single_succ_p (a)
4873 1847695 : && single_succ (a) == b
4874 1847695 : && single_pred_p (b) == 1
4875 1822578 : && a != b
4876 : /* Must be simple edge. */
4877 1822578 : && !(single_succ_edge (a)->flags & EDGE_COMPLEX)
4878 1822578 : && a != ENTRY_BLOCK_PTR_FOR_FN (cfun)
4879 1822578 : && b != EXIT_BLOCK_PTR_FOR_FN (cfun)
4880 : /* If the jump insn has side effects, we can't kill the edge.
4881 : When not optimizing, try_redirect_by_replacing_jump will
4882 : not allow us to redirect an edge by replacing a table jump. */
4883 3670273 : && (!JUMP_P (BB_END (a))
4884 63622 : || ((!optimize || reload_completed)
4885 50650 : ? simplejump_p (BB_END (a)) : onlyjump_p (BB_END (a)))));
4886 : }
4887 :
4888 : /* Merge block A and B. The blocks must be mergeable. */
4889 :
4890 : static void
4891 909989 : cfg_layout_merge_blocks (basic_block a, basic_block b)
4892 : {
4893 : /* If B is a forwarder block whose outgoing edge has no location, we'll
4894 : propagate the locus of the edge between A and B onto it. */
4895 909989 : const bool forward_edge_locus
4896 909989 : = (b->flags & BB_FORWARDER_BLOCK) != 0
4897 909989 : && LOCATION_LOCUS (EDGE_SUCC (b, 0)->goto_locus) == UNKNOWN_LOCATION;
4898 909989 : rtx_insn *insn;
4899 :
4900 909989 : gcc_checking_assert (cfg_layout_can_merge_blocks_p (a, b));
4901 :
4902 909989 : if (dump_file)
4903 74 : fprintf (dump_file, "Merging block %d into block %d...\n", b->index,
4904 : a->index);
4905 :
4906 : /* If there was a CODE_LABEL beginning B, delete it. */
4907 909989 : if (LABEL_P (BB_HEAD (b)))
4908 : {
4909 384287 : delete_insn (BB_HEAD (b));
4910 : }
4911 :
4912 : /* We should have fallthru edge in a, or we can do dummy redirection to get
4913 : it cleaned up. */
4914 909989 : if (JUMP_P (BB_END (a)))
4915 24025 : try_redirect_by_replacing_jump (EDGE_SUCC (a, 0), b, true);
4916 909989 : gcc_assert (!JUMP_P (BB_END (a)));
4917 :
4918 : /* If not optimizing, preserve the locus of the single edge between
4919 : blocks A and B if necessary by emitting a nop. */
4920 909989 : if (!optimize
4921 2617 : && !forward_edge_locus
4922 912169 : && !DECL_IGNORED_P (current_function_decl))
4923 2180 : emit_nop_for_unique_locus_between (a, b);
4924 :
4925 : /* Move things from b->footer after a->footer. */
4926 909989 : if (BB_FOOTER (b))
4927 : {
4928 206698 : if (!BB_FOOTER (a))
4929 206698 : BB_FOOTER (a) = BB_FOOTER (b);
4930 : else
4931 : {
4932 : rtx_insn *last = BB_FOOTER (a);
4933 :
4934 0 : while (NEXT_INSN (last))
4935 : last = NEXT_INSN (last);
4936 0 : SET_NEXT_INSN (last) = BB_FOOTER (b);
4937 0 : SET_PREV_INSN (BB_FOOTER (b)) = last;
4938 : }
4939 206698 : BB_FOOTER (b) = NULL;
4940 : }
4941 :
4942 : /* Move things from b->header before a->footer.
4943 : Note that this may include dead tablejump data, but we don't clean
4944 : those up until we go out of cfglayout mode. */
4945 909989 : if (BB_HEADER (b))
4946 : {
4947 2222 : if (! BB_FOOTER (a))
4948 1042 : BB_FOOTER (a) = BB_HEADER (b);
4949 : else
4950 : {
4951 : rtx_insn *last = BB_HEADER (b);
4952 :
4953 1365 : while (NEXT_INSN (last))
4954 : last = NEXT_INSN (last);
4955 1180 : SET_NEXT_INSN (last) = BB_FOOTER (a);
4956 1180 : SET_PREV_INSN (BB_FOOTER (a)) = last;
4957 1180 : BB_FOOTER (a) = BB_HEADER (b);
4958 : }
4959 2222 : BB_HEADER (b) = NULL;
4960 : }
4961 :
4962 : /* In the case basic blocks are not adjacent, move them around. */
4963 909989 : if (NEXT_INSN (BB_END (a)) != BB_HEAD (b))
4964 : {
4965 443065 : insn = unlink_insn_chain (BB_HEAD (b), BB_END (b));
4966 :
4967 443065 : emit_insn_after_noloc (insn, BB_END (a), a);
4968 : }
4969 : /* Otherwise just re-associate the instructions. */
4970 : else
4971 : {
4972 466924 : insn = BB_HEAD (b);
4973 466924 : BB_END (a) = BB_END (b);
4974 : }
4975 :
4976 : /* emit_insn_after_noloc doesn't call df_insn_change_bb.
4977 : We need to explicitly call. */
4978 909989 : update_bb_for_insn_chain (insn, BB_END (b), a);
4979 :
4980 : /* Skip possible DELETED_LABEL insn. */
4981 909989 : if (!NOTE_INSN_BASIC_BLOCK_P (insn))
4982 0 : insn = NEXT_INSN (insn);
4983 909989 : gcc_assert (NOTE_INSN_BASIC_BLOCK_P (insn));
4984 909989 : BB_HEAD (b) = BB_END (b) = NULL;
4985 909989 : delete_insn (insn);
4986 :
4987 909989 : df_bb_delete (b->index);
4988 :
4989 909989 : if (forward_edge_locus)
4990 178257 : EDGE_SUCC (b, 0)->goto_locus = EDGE_SUCC (a, 0)->goto_locus;
4991 :
4992 909989 : if (dump_file)
4993 74 : fprintf (dump_file, "Merged blocks %d and %d.\n", a->index, b->index);
4994 909989 : }
4995 :
4996 : /* Split edge E. */
4997 :
4998 : static basic_block
4999 3539194 : cfg_layout_split_edge (edge e)
5000 : {
5001 3539194 : basic_block new_bb =
5002 7078388 : create_basic_block (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
5003 3539194 : ? NEXT_INSN (BB_END (e->src)) : get_insns (),
5004 : NULL_RTX, e->src);
5005 :
5006 3539194 : if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
5007 1 : BB_COPY_PARTITION (new_bb, e->src);
5008 : else
5009 3539193 : BB_COPY_PARTITION (new_bb, e->dest);
5010 3539194 : make_edge (new_bb, e->dest, EDGE_FALLTHRU);
5011 3539194 : redirect_edge_and_branch_force (e, new_bb);
5012 :
5013 3539194 : return new_bb;
5014 : }
5015 :
5016 : /* Do postprocessing after making a forwarder block joined by edge FALLTHRU. */
5017 :
5018 : static void
5019 1181 : rtl_make_forwarder_block (edge fallthru ATTRIBUTE_UNUSED)
5020 : {
5021 1181 : }
5022 :
5023 : /* Return true if BB contains only labels or non-executable
5024 : instructions. */
5025 :
5026 : static bool
5027 0 : rtl_block_empty_p (basic_block bb)
5028 : {
5029 0 : rtx_insn *insn;
5030 :
5031 0 : if (bb == ENTRY_BLOCK_PTR_FOR_FN (cfun)
5032 0 : || bb == EXIT_BLOCK_PTR_FOR_FN (cfun))
5033 : return true;
5034 :
5035 0 : FOR_BB_INSNS (bb, insn)
5036 0 : if (NONDEBUG_INSN_P (insn)
5037 0 : && (!any_uncondjump_p (insn) || !onlyjump_p (insn)))
5038 0 : return false;
5039 :
5040 : return true;
5041 : }
5042 :
5043 : /* Split a basic block if it ends with a conditional branch and if
5044 : the other part of the block is not empty. */
5045 :
5046 : static basic_block
5047 0 : rtl_split_block_before_cond_jump (basic_block bb)
5048 : {
5049 0 : rtx_insn *insn;
5050 0 : rtx_insn *split_point = NULL;
5051 0 : rtx_insn *last = NULL;
5052 0 : bool found_code = false;
5053 :
5054 0 : FOR_BB_INSNS (bb, insn)
5055 : {
5056 0 : if (any_condjump_p (insn))
5057 : split_point = last;
5058 0 : else if (NONDEBUG_INSN_P (insn))
5059 0 : found_code = true;
5060 0 : last = insn;
5061 : }
5062 :
5063 : /* Did not find everything. */
5064 0 : if (found_code && split_point)
5065 0 : return split_block (bb, split_point)->dest;
5066 : else
5067 : return NULL;
5068 : }
5069 :
5070 : /* Return true if BB ends with a call, possibly followed by some
5071 : instructions that must stay with the call, false otherwise. */
5072 :
5073 : static bool
5074 9808656 : rtl_block_ends_with_call_p (basic_block bb)
5075 : {
5076 9808656 : rtx_insn *insn = BB_END (bb);
5077 :
5078 9808656 : while (!CALL_P (insn)
5079 11145406 : && insn != BB_HEAD (bb)
5080 23554128 : && (keep_with_call_p (insn)
5081 11094447 : || NOTE_P (insn)
5082 10973425 : || DEBUG_INSN_P (insn)))
5083 2650674 : insn = PREV_INSN (insn);
5084 9808656 : return (CALL_P (insn));
5085 : }
5086 :
5087 : /* Return true if BB ends with a conditional branch, false otherwise. */
5088 :
5089 : static bool
5090 0 : rtl_block_ends_with_condjump_p (const_basic_block bb)
5091 : {
5092 0 : return any_condjump_p (BB_END (bb));
5093 : }
5094 :
5095 : /* Return true if we need to add fake edge to exit.
5096 : Helper function for rtl_flow_call_edges_add. */
5097 :
5098 : static bool
5099 0 : need_fake_edge_p (const rtx_insn *insn)
5100 : {
5101 0 : if (!INSN_P (insn))
5102 : return false;
5103 :
5104 0 : if ((CALL_P (insn)
5105 0 : && !SIBLING_CALL_P (insn)
5106 0 : && !find_reg_note (insn, REG_NORETURN, NULL)
5107 0 : && !(RTL_CONST_OR_PURE_CALL_P (insn))))
5108 : return true;
5109 :
5110 0 : return ((GET_CODE (PATTERN (insn)) == ASM_OPERANDS
5111 0 : && MEM_VOLATILE_P (PATTERN (insn)))
5112 0 : || (GET_CODE (PATTERN (insn)) == PARALLEL
5113 0 : && asm_noperands (insn) != -1
5114 0 : && MEM_VOLATILE_P (XVECEXP (PATTERN (insn), 0, 0)))
5115 0 : || GET_CODE (PATTERN (insn)) == ASM_INPUT);
5116 : }
5117 :
5118 : /* Add fake edges to the function exit for any non constant and non noreturn
5119 : calls, volatile inline assembly in the bitmap of blocks specified by
5120 : BLOCKS or to the whole CFG if BLOCKS is zero. Return the number of blocks
5121 : that were split.
5122 :
5123 : The goal is to expose cases in which entering a basic block does not imply
5124 : that all subsequent instructions must be executed. */
5125 :
5126 : static int
5127 0 : rtl_flow_call_edges_add (sbitmap blocks)
5128 : {
5129 0 : int i;
5130 0 : int blocks_split = 0;
5131 0 : int last_bb = last_basic_block_for_fn (cfun);
5132 0 : bool check_last_block = false;
5133 :
5134 0 : if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS)
5135 : return 0;
5136 :
5137 0 : if (! blocks)
5138 : check_last_block = true;
5139 : else
5140 0 : check_last_block = bitmap_bit_p (blocks,
5141 0 : EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb->index);
5142 :
5143 : /* In the last basic block, before epilogue generation, there will be
5144 : a fallthru edge to EXIT. Special care is required if the last insn
5145 : of the last basic block is a call because make_edge folds duplicate
5146 : edges, which would result in the fallthru edge also being marked
5147 : fake, which would result in the fallthru edge being removed by
5148 : remove_fake_edges, which would result in an invalid CFG.
5149 :
5150 : Moreover, we can't elide the outgoing fake edge, since the block
5151 : profiler needs to take this into account in order to solve the minimal
5152 : spanning tree in the case that the call doesn't return.
5153 :
5154 : Handle this by adding a dummy instruction in a new last basic block. */
5155 0 : if (check_last_block)
5156 : {
5157 0 : basic_block bb = EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb;
5158 0 : rtx_insn *insn = BB_END (bb);
5159 :
5160 : /* Back up past insns that must be kept in the same block as a call. */
5161 0 : while (insn != BB_HEAD (bb)
5162 0 : && keep_with_call_p (insn))
5163 0 : insn = PREV_INSN (insn);
5164 :
5165 0 : if (need_fake_edge_p (insn))
5166 : {
5167 0 : edge e;
5168 :
5169 0 : e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun));
5170 0 : if (e)
5171 : {
5172 0 : insert_insn_on_edge (gen_use (const0_rtx), e);
5173 0 : commit_edge_insertions ();
5174 : }
5175 : }
5176 : }
5177 :
5178 : /* Now add fake edges to the function exit for any non constant
5179 : calls since there is no way that we can determine if they will
5180 : return or not... */
5181 :
5182 0 : for (i = NUM_FIXED_BLOCKS; i < last_bb; i++)
5183 : {
5184 0 : basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i);
5185 0 : rtx_insn *insn;
5186 0 : rtx_insn *prev_insn;
5187 :
5188 0 : if (!bb)
5189 0 : continue;
5190 :
5191 0 : if (blocks && !bitmap_bit_p (blocks, i))
5192 0 : continue;
5193 :
5194 0 : for (insn = BB_END (bb); ; insn = prev_insn)
5195 : {
5196 0 : prev_insn = PREV_INSN (insn);
5197 0 : if (need_fake_edge_p (insn))
5198 : {
5199 0 : edge e;
5200 0 : rtx_insn *split_at_insn = insn;
5201 :
5202 : /* Don't split the block between a call and an insn that should
5203 : remain in the same block as the call. */
5204 0 : if (CALL_P (insn))
5205 0 : while (split_at_insn != BB_END (bb)
5206 0 : && keep_with_call_p (NEXT_INSN (split_at_insn)))
5207 0 : split_at_insn = NEXT_INSN (split_at_insn);
5208 :
5209 : /* The handling above of the final block before the epilogue
5210 : should be enough to verify that there is no edge to the exit
5211 : block in CFG already. Calling make_edge in such case would
5212 : cause us to mark that edge as fake and remove it later. */
5213 :
5214 0 : if (flag_checking && split_at_insn == BB_END (bb))
5215 : {
5216 0 : e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun));
5217 0 : gcc_assert (e == NULL);
5218 : }
5219 :
5220 : /* Note that the following may create a new basic block
5221 : and renumber the existing basic blocks. */
5222 0 : if (split_at_insn != BB_END (bb))
5223 : {
5224 0 : e = split_block (bb, split_at_insn);
5225 0 : if (e)
5226 0 : blocks_split++;
5227 : }
5228 :
5229 0 : edge ne = make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_FAKE);
5230 0 : ne->probability = profile_probability::guessed_never ();
5231 : }
5232 :
5233 0 : if (insn == BB_HEAD (bb))
5234 : break;
5235 : }
5236 : }
5237 :
5238 0 : if (blocks_split)
5239 0 : verify_flow_info ();
5240 :
5241 : return blocks_split;
5242 : }
5243 :
5244 : /* Add COMP_RTX as a condition at end of COND_BB. FIRST_HEAD is
5245 : the conditional branch target, SECOND_HEAD should be the fall-thru
5246 : there is no need to handle this here the loop versioning code handles
5247 : this. the reason for SECON_HEAD is that it is needed for condition
5248 : in trees, and this should be of the same type since it is a hook. */
5249 : static void
5250 0 : rtl_lv_add_condition_to_bb (basic_block first_head ,
5251 : basic_block second_head ATTRIBUTE_UNUSED,
5252 : basic_block cond_bb, void *comp_rtx)
5253 : {
5254 0 : rtx_code_label *label;
5255 0 : rtx_insn *seq, *jump;
5256 0 : rtx op0 = XEXP ((rtx)comp_rtx, 0);
5257 0 : rtx op1 = XEXP ((rtx)comp_rtx, 1);
5258 0 : enum rtx_code comp = GET_CODE ((rtx)comp_rtx);
5259 0 : machine_mode mode;
5260 :
5261 :
5262 0 : label = block_label (first_head);
5263 0 : mode = GET_MODE (op0);
5264 0 : if (mode == VOIDmode)
5265 0 : mode = GET_MODE (op1);
5266 :
5267 0 : start_sequence ();
5268 0 : op0 = force_operand (op0, NULL_RTX);
5269 0 : op1 = force_operand (op1, NULL_RTX);
5270 0 : do_compare_rtx_and_jump (op0, op1, comp, 0, mode, NULL_RTX, NULL, label,
5271 : profile_probability::uninitialized ());
5272 0 : jump = get_last_insn ();
5273 0 : JUMP_LABEL (jump) = label;
5274 0 : LABEL_NUSES (label)++;
5275 0 : seq = end_sequence ();
5276 :
5277 : /* Add the new cond, in the new head. */
5278 0 : emit_insn_after (seq, BB_END (cond_bb));
5279 0 : }
5280 :
5281 :
5282 : /* Given a block B with unconditional branch at its end, get the
5283 : store the return the branch edge and the fall-thru edge in
5284 : BRANCH_EDGE and FALLTHRU_EDGE respectively. */
5285 : static void
5286 0 : rtl_extract_cond_bb_edges (basic_block b, edge *branch_edge,
5287 : edge *fallthru_edge)
5288 : {
5289 0 : edge e = EDGE_SUCC (b, 0);
5290 :
5291 0 : if (e->flags & EDGE_FALLTHRU)
5292 : {
5293 0 : *fallthru_edge = e;
5294 0 : *branch_edge = EDGE_SUCC (b, 1);
5295 : }
5296 : else
5297 : {
5298 0 : *branch_edge = e;
5299 0 : *fallthru_edge = EDGE_SUCC (b, 1);
5300 : }
5301 0 : }
5302 :
5303 : void
5304 28574459 : init_rtl_bb_info (basic_block bb)
5305 : {
5306 28574459 : gcc_assert (!bb->il.x.rtl);
5307 28574459 : bb->il.x.head_ = NULL;
5308 28574459 : bb->il.x.rtl = ggc_cleared_alloc<rtl_bb_info> ();
5309 28574459 : }
5310 :
5311 : static bool
5312 2137 : rtl_bb_info_initialized_p (basic_block bb)
5313 : {
5314 2137 : return bb->il.x.rtl;
5315 : }
5316 :
5317 : /* Returns true if it is possible to remove edge E by redirecting
5318 : it to the destination of the other edge from E->src. */
5319 :
5320 : static bool
5321 144276 : rtl_can_remove_branch_p (const_edge e)
5322 : {
5323 144276 : const_basic_block src = e->src;
5324 144276 : const_basic_block target = EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest;
5325 144276 : const rtx_insn *insn = BB_END (src);
5326 144276 : rtx set;
5327 :
5328 : /* The conditions are taken from try_redirect_by_replacing_jump. */
5329 144276 : if (target == EXIT_BLOCK_PTR_FOR_FN (cfun))
5330 : return false;
5331 :
5332 144276 : if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
5333 : return false;
5334 :
5335 144276 : if (BB_PARTITION (src) != BB_PARTITION (target))
5336 : return false;
5337 :
5338 144276 : if (!onlyjump_p (insn)
5339 144276 : || tablejump_p (insn, NULL, NULL))
5340 0 : return false;
5341 :
5342 144276 : set = single_set (insn);
5343 144276 : if (!set || side_effects_p (set))
5344 0 : return false;
5345 :
5346 : return true;
5347 : }
5348 :
5349 : static basic_block
5350 41185 : rtl_duplicate_bb (basic_block bb, copy_bb_data *id)
5351 : {
5352 41185 : bb = cfg_layout_duplicate_bb (bb, id);
5353 41185 : bb->aux = NULL;
5354 41185 : return bb;
5355 : }
5356 :
5357 : /* Do book-keeping of basic block BB for the profile consistency checker.
5358 : Store the counting in RECORD. */
5359 : static void
5360 0 : rtl_account_profile_record (basic_block bb, struct profile_record *record)
5361 : {
5362 0 : rtx_insn *insn;
5363 0 : FOR_BB_INSNS (bb, insn)
5364 0 : if (INSN_P (insn))
5365 : {
5366 0 : record->size += insn_cost (insn, false);
5367 0 : if (profile_info)
5368 : {
5369 0 : if (ENTRY_BLOCK_PTR_FOR_FN (cfun)->count.ipa ().initialized_p ()
5370 0 : && ENTRY_BLOCK_PTR_FOR_FN (cfun)->count.ipa ().nonzero_p ()
5371 0 : && bb->count.ipa ().initialized_p ())
5372 0 : record->time
5373 0 : += insn_cost (insn, true) * bb->count.ipa ().to_gcov_type ();
5374 : }
5375 0 : else if (bb->count.initialized_p ()
5376 0 : && ENTRY_BLOCK_PTR_FOR_FN (cfun)->count.initialized_p ())
5377 0 : record->time
5378 0 : += insn_cost (insn, true)
5379 0 : * bb->count.to_sreal_scale
5380 0 : (ENTRY_BLOCK_PTR_FOR_FN (cfun)->count).to_double ();
5381 : else
5382 0 : record->time += insn_cost (insn, true);
5383 : }
5384 0 : }
5385 :
5386 : /* Implementation of CFG manipulation for linearized RTL. */
5387 : struct cfg_hooks rtl_cfg_hooks = {
5388 : "rtl",
5389 : rtl_verify_flow_info,
5390 : rtl_dump_bb,
5391 : rtl_dump_bb_for_graph,
5392 : rtl_dump_bb_as_sarif_properties,
5393 : rtl_create_basic_block,
5394 : rtl_redirect_edge_and_branch,
5395 : rtl_redirect_edge_and_branch_force,
5396 : rtl_can_remove_branch_p,
5397 : rtl_delete_block,
5398 : rtl_split_block,
5399 : rtl_move_block_after,
5400 : rtl_can_merge_blocks, /* can_merge_blocks_p */
5401 : rtl_merge_blocks,
5402 : rtl_predict_edge,
5403 : rtl_predicted_by_p,
5404 : cfg_layout_can_duplicate_bb_p,
5405 : rtl_duplicate_bb,
5406 : rtl_split_edge,
5407 : rtl_make_forwarder_block,
5408 : rtl_tidy_fallthru_edge,
5409 : rtl_force_nonfallthru,
5410 : rtl_block_ends_with_call_p,
5411 : rtl_block_ends_with_condjump_p,
5412 : rtl_flow_call_edges_add,
5413 : NULL, /* execute_on_growing_pred */
5414 : NULL, /* execute_on_shrinking_pred */
5415 : NULL, /* duplicate loop for trees */
5416 : NULL, /* lv_add_condition_to_bb */
5417 : NULL, /* lv_adjust_loop_header_phi*/
5418 : NULL, /* extract_cond_bb_edges */
5419 : NULL, /* flush_pending_stmts */
5420 : rtl_block_empty_p, /* block_empty_p */
5421 : rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */
5422 : rtl_account_profile_record,
5423 : };
5424 :
5425 : /* Implementation of CFG manipulation for cfg layout RTL, where
5426 : basic block connected via fallthru edges does not have to be adjacent.
5427 : This representation will hopefully become the default one in future
5428 : version of the compiler. */
5429 :
5430 : struct cfg_hooks cfg_layout_rtl_cfg_hooks = {
5431 : "cfglayout mode",
5432 : rtl_verify_flow_info_1,
5433 : rtl_dump_bb,
5434 : rtl_dump_bb_for_graph,
5435 : rtl_dump_bb_as_sarif_properties,
5436 : cfg_layout_create_basic_block,
5437 : cfg_layout_redirect_edge_and_branch,
5438 : cfg_layout_redirect_edge_and_branch_force,
5439 : rtl_can_remove_branch_p,
5440 : cfg_layout_delete_block,
5441 : cfg_layout_split_block,
5442 : rtl_move_block_after,
5443 : cfg_layout_can_merge_blocks_p,
5444 : cfg_layout_merge_blocks,
5445 : rtl_predict_edge,
5446 : rtl_predicted_by_p,
5447 : cfg_layout_can_duplicate_bb_p,
5448 : cfg_layout_duplicate_bb,
5449 : cfg_layout_split_edge,
5450 : rtl_make_forwarder_block,
5451 : NULL, /* tidy_fallthru_edge */
5452 : rtl_force_nonfallthru,
5453 : rtl_block_ends_with_call_p,
5454 : rtl_block_ends_with_condjump_p,
5455 : rtl_flow_call_edges_add,
5456 : NULL, /* execute_on_growing_pred */
5457 : NULL, /* execute_on_shrinking_pred */
5458 : duplicate_loop_body_to_header_edge, /* duplicate loop for rtl */
5459 : rtl_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
5460 : NULL, /* lv_adjust_loop_header_phi*/
5461 : rtl_extract_cond_bb_edges, /* extract_cond_bb_edges */
5462 : NULL, /* flush_pending_stmts */
5463 : rtl_block_empty_p, /* block_empty_p */
5464 : rtl_split_block_before_cond_jump, /* split_block_before_cond_jump */
5465 : rtl_account_profile_record,
5466 : };
5467 :
5468 : #include "gt-cfgrtl.h"
5469 :
5470 : #if __GNUC__ >= 10
5471 : # pragma GCC diagnostic pop
5472 : #endif
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