1 /* Instruction scheduling pass. 2 Copyright (C) 1992-2017 Free Software Foundation, Inc. 3 Contributed by Michael Tiemann (tiemann@cygnus.com) Enhanced by, 4 and currently maintained by, Jim Wilson (wilson@cygnus.com) 5 6 This file is part of GCC. 7 8 GCC is free software; you can redistribute it and/or modify it under 9 the terms of the GNU General Public License as published by the Free 10 Software Foundation; either version 3, or (at your option) any later 11 version. 12 13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 14 WARRANTY; without even the implied warranty of MERCHANTABILITY or 15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 16 for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with GCC; see the file COPYING3. If not see 20 <http://www.gnu.org/licenses/>. */ 21 22 #include "config.h" 23 #include "system.h" 24 #include "coretypes.h" 25 #include "backend.h" 26 #include "target.h" 27 #include "rtl.h" 28 #include "cfghooks.h" 29 #include "df.h" 30 #include "profile.h" 31 #include "insn-attr.h" 32 #include "params.h" 33 #include "cfgrtl.h" 34 #include "cfgbuild.h" 35 #include "sched-int.h" 36 37 38 #ifdef INSN_SCHEDULING 39 40 /* The number of insns to be scheduled in total. */ 41 static int rgn_n_insns; 42 43 /* The number of insns scheduled so far. */ 44 static int sched_rgn_n_insns; 45 46 /* Set of blocks, that already have their dependencies calculated. */ 47 static bitmap_head dont_calc_deps; 48 49 /* Last basic block in current ebb. */ 50 static basic_block last_bb; 51 52 /* Implementations of the sched_info functions for region scheduling. */ 53 static void init_ready_list (void); 54 static void begin_schedule_ready (rtx_insn *); 55 static int schedule_more_p (void); 56 static const char *ebb_print_insn (const rtx_insn *, int); 57 static int rank (rtx_insn *, rtx_insn *); 58 static int ebb_contributes_to_priority (rtx_insn *, rtx_insn *); 59 static basic_block earliest_block_with_similiar_load (basic_block, rtx); 60 static void add_deps_for_risky_insns (rtx_insn *, rtx_insn *); 61 static void debug_ebb_dependencies (rtx_insn *, rtx_insn *); 62 63 static void ebb_add_remove_insn (rtx_insn *, int); 64 static void ebb_add_block (basic_block, basic_block); 65 static basic_block advance_target_bb (basic_block, rtx_insn *); 66 static void ebb_fix_recovery_cfg (int, int, int); 67 68 /* Allocate memory and store the state of the frontend. Return the allocated 69 memory. */ 70 static void * 71 save_ebb_state (void) 72 { 73 int *p = XNEW (int); 74 *p = sched_rgn_n_insns; 75 return p; 76 } 77 78 /* Restore the state of the frontend from P_, then free it. */ 79 static void 80 restore_ebb_state (void *p_) 81 { 82 int *p = (int *)p_; 83 sched_rgn_n_insns = *p; 84 free (p_); 85 } 86 87 /* Return nonzero if there are more insns that should be scheduled. */ 88 89 static int 90 schedule_more_p (void) 91 { 92 return sched_rgn_n_insns < rgn_n_insns; 93 } 94 95 /* Print dependency information about ebb between HEAD and TAIL. */ 96 static void 97 debug_ebb_dependencies (rtx_insn *head, rtx_insn *tail) 98 { 99 fprintf (sched_dump, 100 ";; --------------- forward dependences: ------------ \n"); 101 102 fprintf (sched_dump, "\n;; --- EBB Dependences --- from bb%d to bb%d \n", 103 BLOCK_NUM (head), BLOCK_NUM (tail)); 104 105 debug_dependencies (head, tail); 106 } 107 108 /* Add all insns that are initially ready to the ready list READY. Called 109 once before scheduling a set of insns. */ 110 111 static void 112 init_ready_list (void) 113 { 114 int n = 0; 115 rtx_insn *prev_head = current_sched_info->prev_head; 116 rtx_insn *next_tail = current_sched_info->next_tail; 117 rtx_insn *insn; 118 119 sched_rgn_n_insns = 0; 120 121 /* Print debugging information. */ 122 if (sched_verbose >= 5) 123 debug_ebb_dependencies (NEXT_INSN (prev_head), PREV_INSN (next_tail)); 124 125 /* Initialize ready list with all 'ready' insns in target block. 126 Count number of insns in the target block being scheduled. */ 127 for (insn = NEXT_INSN (prev_head); insn != next_tail; insn = NEXT_INSN (insn)) 128 { 129 try_ready (insn); 130 n++; 131 } 132 133 gcc_assert (n == rgn_n_insns); 134 } 135 136 /* INSN is being scheduled after LAST. Update counters. */ 137 static void 138 begin_schedule_ready (rtx_insn *insn ATTRIBUTE_UNUSED) 139 { 140 sched_rgn_n_insns++; 141 } 142 143 /* INSN is being moved to its place in the schedule, after LAST. */ 144 static void 145 begin_move_insn (rtx_insn *insn, rtx_insn *last) 146 { 147 if (BLOCK_FOR_INSN (insn) == last_bb 148 /* INSN is a jump in the last block, ... */ 149 && control_flow_insn_p (insn) 150 /* that is going to be moved over some instructions. */ 151 && last != PREV_INSN (insn)) 152 { 153 edge e; 154 basic_block bb; 155 156 /* An obscure special case, where we do have partially dead 157 instruction scheduled after last control flow instruction. 158 In this case we can create new basic block. It is 159 always exactly one basic block last in the sequence. */ 160 161 e = find_fallthru_edge (last_bb->succs); 162 163 gcc_checking_assert (!e || !(e->flags & EDGE_COMPLEX)); 164 165 gcc_checking_assert (BLOCK_FOR_INSN (insn) == last_bb 166 && !IS_SPECULATION_CHECK_P (insn) 167 && BB_HEAD (last_bb) != insn 168 && BB_END (last_bb) == insn); 169 170 { 171 rtx_insn *x = NEXT_INSN (insn); 172 if (e) 173 gcc_checking_assert (NOTE_P (x) || LABEL_P (x)); 174 else 175 gcc_checking_assert (BARRIER_P (x)); 176 } 177 178 if (e) 179 { 180 bb = split_edge (e); 181 gcc_assert (NOTE_INSN_BASIC_BLOCK_P (BB_END (bb))); 182 } 183 else 184 { 185 /* Create an empty unreachable block after the INSN. */ 186 rtx_insn *next = NEXT_INSN (insn); 187 if (next && BARRIER_P (next)) 188 next = NEXT_INSN (next); 189 bb = create_basic_block (next, NULL_RTX, last_bb); 190 } 191 192 /* split_edge () creates BB before E->DEST. Keep in mind, that 193 this operation extends scheduling region till the end of BB. 194 Hence, we need to shift NEXT_TAIL, so haifa-sched.c won't go out 195 of the scheduling region. */ 196 current_sched_info->next_tail = NEXT_INSN (BB_END (bb)); 197 gcc_assert (current_sched_info->next_tail); 198 199 /* Append new basic block to the end of the ebb. */ 200 sched_init_only_bb (bb, last_bb); 201 gcc_assert (last_bb == bb); 202 } 203 } 204 205 /* Return a string that contains the insn uid and optionally anything else 206 necessary to identify this insn in an output. It's valid to use a 207 static buffer for this. The ALIGNED parameter should cause the string 208 to be formatted so that multiple output lines will line up nicely. */ 209 210 static const char * 211 ebb_print_insn (const rtx_insn *insn, int aligned ATTRIBUTE_UNUSED) 212 { 213 static char tmp[80]; 214 215 /* '+' before insn means it is a new cycle start. */ 216 if (GET_MODE (insn) == TImode) 217 sprintf (tmp, "+ %4d", INSN_UID (insn)); 218 else 219 sprintf (tmp, " %4d", INSN_UID (insn)); 220 221 return tmp; 222 } 223 224 /* Compare priority of two insns. Return a positive number if the second 225 insn is to be preferred for scheduling, and a negative one if the first 226 is to be preferred. Zero if they are equally good. */ 227 228 static int 229 rank (rtx_insn *insn1, rtx_insn *insn2) 230 { 231 basic_block bb1 = BLOCK_FOR_INSN (insn1); 232 basic_block bb2 = BLOCK_FOR_INSN (insn2); 233 234 if (bb1->count > bb2->count 235 || bb1->frequency > bb2->frequency) 236 return -1; 237 if (bb1->count < bb2->count 238 || bb1->frequency < bb2->frequency) 239 return 1; 240 return 0; 241 } 242 243 /* NEXT is an instruction that depends on INSN (a backward dependence); 244 return nonzero if we should include this dependence in priority 245 calculations. */ 246 247 static int 248 ebb_contributes_to_priority (rtx_insn *next ATTRIBUTE_UNUSED, 249 rtx_insn *insn ATTRIBUTE_UNUSED) 250 { 251 return 1; 252 } 253 254 /* INSN is a JUMP_INSN. Store the set of registers that 255 must be considered as used by this jump in USED. */ 256 257 void 258 ebb_compute_jump_reg_dependencies (rtx insn, regset used) 259 { 260 basic_block b = BLOCK_FOR_INSN (insn); 261 edge e; 262 edge_iterator ei; 263 264 FOR_EACH_EDGE (e, ei, b->succs) 265 if ((e->flags & EDGE_FALLTHRU) == 0) 266 bitmap_ior_into (used, df_get_live_in (e->dest)); 267 } 268 269 /* Used in schedule_insns to initialize current_sched_info for scheduling 270 regions (or single basic blocks). */ 271 272 static struct common_sched_info_def ebb_common_sched_info; 273 274 static struct sched_deps_info_def ebb_sched_deps_info = 275 { 276 ebb_compute_jump_reg_dependencies, 277 NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 278 NULL, 279 1, 0, 0 280 }; 281 282 static struct haifa_sched_info ebb_sched_info = 283 { 284 init_ready_list, 285 NULL, 286 schedule_more_p, 287 NULL, 288 rank, 289 ebb_print_insn, 290 ebb_contributes_to_priority, 291 NULL, /* insn_finishes_block_p */ 292 293 NULL, NULL, 294 NULL, NULL, 295 1, 0, 296 297 ebb_add_remove_insn, 298 begin_schedule_ready, 299 begin_move_insn, 300 advance_target_bb, 301 302 save_ebb_state, 303 restore_ebb_state, 304 305 SCHED_EBB 306 /* We can create new blocks in begin_schedule_ready (). */ 307 | NEW_BBS 308 }; 309 310 /* Returns the earliest block in EBB currently being processed where a 311 "similar load" 'insn2' is found, and hence LOAD_INSN can move 312 speculatively into the found block. All the following must hold: 313 314 (1) both loads have 1 base register (PFREE_CANDIDATEs). 315 (2) load_insn and load2 have a def-use dependence upon 316 the same insn 'insn1'. 317 318 From all these we can conclude that the two loads access memory 319 addresses that differ at most by a constant, and hence if moving 320 load_insn would cause an exception, it would have been caused by 321 load2 anyhow. 322 323 The function uses list (given by LAST_BLOCK) of already processed 324 blocks in EBB. The list is formed in `add_deps_for_risky_insns'. */ 325 326 static basic_block 327 earliest_block_with_similiar_load (basic_block last_block, rtx load_insn) 328 { 329 sd_iterator_def back_sd_it; 330 dep_t back_dep; 331 basic_block bb, earliest_block = NULL; 332 333 FOR_EACH_DEP (load_insn, SD_LIST_BACK, back_sd_it, back_dep) 334 { 335 rtx_insn *insn1 = DEP_PRO (back_dep); 336 337 if (DEP_TYPE (back_dep) == REG_DEP_TRUE) 338 /* Found a DEF-USE dependence (insn1, load_insn). */ 339 { 340 sd_iterator_def fore_sd_it; 341 dep_t fore_dep; 342 343 FOR_EACH_DEP (insn1, SD_LIST_FORW, fore_sd_it, fore_dep) 344 { 345 rtx_insn *insn2 = DEP_CON (fore_dep); 346 basic_block insn2_block = BLOCK_FOR_INSN (insn2); 347 348 if (DEP_TYPE (fore_dep) == REG_DEP_TRUE) 349 { 350 if (earliest_block != NULL 351 && earliest_block->index < insn2_block->index) 352 continue; 353 354 /* Found a DEF-USE dependence (insn1, insn2). */ 355 if (haifa_classify_insn (insn2) != PFREE_CANDIDATE) 356 /* insn2 not guaranteed to be a 1 base reg load. */ 357 continue; 358 359 for (bb = last_block; bb; bb = (basic_block) bb->aux) 360 if (insn2_block == bb) 361 break; 362 363 if (!bb) 364 /* insn2 is the similar load. */ 365 earliest_block = insn2_block; 366 } 367 } 368 } 369 } 370 371 return earliest_block; 372 } 373 374 /* The following function adds dependencies between jumps and risky 375 insns in given ebb. */ 376 377 static void 378 add_deps_for_risky_insns (rtx_insn *head, rtx_insn *tail) 379 { 380 rtx_insn *insn, *prev; 381 int classification; 382 rtx_insn *last_jump = NULL; 383 rtx_insn *next_tail = NEXT_INSN (tail); 384 basic_block last_block = NULL, bb; 385 386 for (insn = head; insn != next_tail; insn = NEXT_INSN (insn)) 387 { 388 add_delay_dependencies (insn); 389 if (control_flow_insn_p (insn)) 390 { 391 bb = BLOCK_FOR_INSN (insn); 392 bb->aux = last_block; 393 last_block = bb; 394 /* Ensure blocks stay in the same order. */ 395 if (last_jump) 396 add_dependence (insn, last_jump, REG_DEP_ANTI); 397 last_jump = insn; 398 } 399 else if (INSN_P (insn) && last_jump != NULL_RTX) 400 { 401 classification = haifa_classify_insn (insn); 402 prev = last_jump; 403 404 switch (classification) 405 { 406 case PFREE_CANDIDATE: 407 if (flag_schedule_speculative_load) 408 { 409 bb = earliest_block_with_similiar_load (last_block, insn); 410 if (bb) 411 { 412 bb = (basic_block) bb->aux; 413 if (!bb) 414 break; 415 prev = BB_END (bb); 416 } 417 } 418 /* Fall through. */ 419 case TRAP_RISKY: 420 case IRISKY: 421 case PRISKY_CANDIDATE: 422 /* ??? We could implement better checking PRISKY_CANDIDATEs 423 analogous to sched-rgn.c. */ 424 /* We can not change the mode of the backward 425 dependency because REG_DEP_ANTI has the lowest 426 rank. */ 427 if (! sched_insns_conditions_mutex_p (insn, prev)) 428 { 429 if ((current_sched_info->flags & DO_SPECULATION) 430 && (spec_info->mask & BEGIN_CONTROL)) 431 { 432 dep_def _dep, *dep = &_dep; 433 434 init_dep (dep, prev, insn, REG_DEP_ANTI); 435 436 if (current_sched_info->flags & USE_DEPS_LIST) 437 { 438 DEP_STATUS (dep) = set_dep_weak (DEP_ANTI, BEGIN_CONTROL, 439 MAX_DEP_WEAK); 440 441 } 442 sd_add_or_update_dep (dep, false); 443 } 444 else 445 add_dependence (insn, prev, REG_DEP_CONTROL); 446 } 447 448 break; 449 450 default: 451 break; 452 } 453 } 454 } 455 /* Maintain the invariant that bb->aux is clear after use. */ 456 while (last_block) 457 { 458 bb = (basic_block) last_block->aux; 459 last_block->aux = NULL; 460 last_block = bb; 461 } 462 } 463 464 /* Schedule a single extended basic block, defined by the boundaries 465 HEAD and TAIL. 466 467 We change our expectations about scheduler behavior depending on 468 whether MODULO_SCHEDULING is true. If it is, we expect that the 469 caller has already called set_modulo_params and created delay pairs 470 as appropriate. If the modulo schedule failed, we return 471 NULL_RTX. */ 472 473 basic_block 474 schedule_ebb (rtx_insn *head, rtx_insn *tail, bool modulo_scheduling) 475 { 476 basic_block first_bb, target_bb; 477 struct deps_desc tmp_deps; 478 bool success; 479 480 /* Blah. We should fix the rest of the code not to get confused by 481 a note or two. */ 482 while (head != tail) 483 { 484 if (NOTE_P (head) || DEBUG_INSN_P (head)) 485 head = NEXT_INSN (head); 486 else if (NOTE_P (tail) || DEBUG_INSN_P (tail)) 487 tail = PREV_INSN (tail); 488 else if (LABEL_P (head)) 489 head = NEXT_INSN (head); 490 else 491 break; 492 } 493 494 first_bb = BLOCK_FOR_INSN (head); 495 last_bb = BLOCK_FOR_INSN (tail); 496 497 if (no_real_insns_p (head, tail)) 498 return BLOCK_FOR_INSN (tail); 499 500 gcc_assert (INSN_P (head) && INSN_P (tail)); 501 502 if (!bitmap_bit_p (&dont_calc_deps, first_bb->index)) 503 { 504 init_deps_global (); 505 506 /* Compute dependencies. */ 507 init_deps (&tmp_deps, false); 508 sched_analyze (&tmp_deps, head, tail); 509 free_deps (&tmp_deps); 510 511 add_deps_for_risky_insns (head, tail); 512 513 if (targetm.sched.dependencies_evaluation_hook) 514 targetm.sched.dependencies_evaluation_hook (head, tail); 515 516 finish_deps_global (); 517 } 518 else 519 /* Only recovery blocks can have their dependencies already calculated, 520 and they always are single block ebbs. */ 521 gcc_assert (first_bb == last_bb); 522 523 /* Set priorities. */ 524 current_sched_info->sched_max_insns_priority = 0; 525 rgn_n_insns = set_priorities (head, tail); 526 current_sched_info->sched_max_insns_priority++; 527 528 current_sched_info->prev_head = PREV_INSN (head); 529 current_sched_info->next_tail = NEXT_INSN (tail); 530 531 remove_notes (head, tail); 532 533 unlink_bb_notes (first_bb, last_bb); 534 535 target_bb = first_bb; 536 537 /* Make ready list big enough to hold all the instructions from the ebb. */ 538 sched_extend_ready_list (rgn_n_insns); 539 success = schedule_block (&target_bb, NULL); 540 gcc_assert (success || modulo_scheduling); 541 542 /* Free ready list. */ 543 sched_finish_ready_list (); 544 545 /* We might pack all instructions into fewer blocks, 546 so we may made some of them empty. Can't assert (b == last_bb). */ 547 548 /* Sanity check: verify that all region insns were scheduled. */ 549 gcc_assert (modulo_scheduling || sched_rgn_n_insns == rgn_n_insns); 550 551 /* Free dependencies. */ 552 sched_free_deps (current_sched_info->head, current_sched_info->tail, true); 553 554 gcc_assert (haifa_recovery_bb_ever_added_p 555 || deps_pools_are_empty_p ()); 556 557 if (EDGE_COUNT (last_bb->preds) == 0) 558 /* LAST_BB is unreachable. */ 559 { 560 gcc_assert (first_bb != last_bb 561 && EDGE_COUNT (last_bb->succs) == 0); 562 last_bb = last_bb->prev_bb; 563 delete_basic_block (last_bb->next_bb); 564 } 565 566 return success ? last_bb : NULL; 567 } 568 569 /* Perform initializations before running schedule_ebbs or a single 570 schedule_ebb. */ 571 void 572 schedule_ebbs_init (void) 573 { 574 /* Setup infos. */ 575 { 576 memcpy (&ebb_common_sched_info, &haifa_common_sched_info, 577 sizeof (ebb_common_sched_info)); 578 579 ebb_common_sched_info.fix_recovery_cfg = ebb_fix_recovery_cfg; 580 ebb_common_sched_info.add_block = ebb_add_block; 581 ebb_common_sched_info.sched_pass_id = SCHED_EBB_PASS; 582 583 common_sched_info = &ebb_common_sched_info; 584 sched_deps_info = &ebb_sched_deps_info; 585 current_sched_info = &ebb_sched_info; 586 } 587 588 haifa_sched_init (); 589 590 compute_bb_for_insn (); 591 592 /* Initialize DONT_CALC_DEPS and ebb-{start, end} markers. */ 593 bitmap_initialize (&dont_calc_deps, 0); 594 bitmap_clear (&dont_calc_deps); 595 } 596 597 /* Perform cleanups after scheduling using schedules_ebbs or schedule_ebb. */ 598 void 599 schedule_ebbs_finish (void) 600 { 601 bitmap_clear (&dont_calc_deps); 602 603 /* Reposition the prologue and epilogue notes in case we moved the 604 prologue/epilogue insns. */ 605 if (reload_completed) 606 reposition_prologue_and_epilogue_notes (); 607 608 haifa_sched_finish (); 609 } 610 611 /* The main entry point in this file. */ 612 613 void 614 schedule_ebbs (void) 615 { 616 basic_block bb; 617 int probability_cutoff; 618 rtx_insn *tail; 619 620 /* Taking care of this degenerate case makes the rest of 621 this code simpler. */ 622 if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS) 623 return; 624 625 if (profile_info && flag_branch_probabilities) 626 probability_cutoff = PARAM_VALUE (TRACER_MIN_BRANCH_PROBABILITY_FEEDBACK); 627 else 628 probability_cutoff = PARAM_VALUE (TRACER_MIN_BRANCH_PROBABILITY); 629 probability_cutoff = REG_BR_PROB_BASE / 100 * probability_cutoff; 630 631 schedule_ebbs_init (); 632 633 /* Schedule every region in the subroutine. */ 634 FOR_EACH_BB_FN (bb, cfun) 635 { 636 rtx_insn *head = BB_HEAD (bb); 637 638 if (bb->flags & BB_DISABLE_SCHEDULE) 639 continue; 640 641 for (;;) 642 { 643 edge e; 644 tail = BB_END (bb); 645 if (bb->next_bb == EXIT_BLOCK_PTR_FOR_FN (cfun) 646 || LABEL_P (BB_HEAD (bb->next_bb))) 647 break; 648 e = find_fallthru_edge (bb->succs); 649 if (! e) 650 break; 651 if (e->probability <= probability_cutoff) 652 break; 653 if (e->dest->flags & BB_DISABLE_SCHEDULE) 654 break; 655 bb = bb->next_bb; 656 } 657 658 bb = schedule_ebb (head, tail, false); 659 } 660 schedule_ebbs_finish (); 661 } 662 663 /* INSN has been added to/removed from current ebb. */ 664 static void 665 ebb_add_remove_insn (rtx_insn *insn ATTRIBUTE_UNUSED, int remove_p) 666 { 667 if (!remove_p) 668 rgn_n_insns++; 669 else 670 rgn_n_insns--; 671 } 672 673 /* BB was added to ebb after AFTER. */ 674 static void 675 ebb_add_block (basic_block bb, basic_block after) 676 { 677 /* Recovery blocks are always bounded by BARRIERS, 678 therefore, they always form single block EBB, 679 therefore, we can use rec->index to identify such EBBs. */ 680 if (after == EXIT_BLOCK_PTR_FOR_FN (cfun)) 681 bitmap_set_bit (&dont_calc_deps, bb->index); 682 else if (after == last_bb) 683 last_bb = bb; 684 } 685 686 /* Return next block in ebb chain. For parameter meaning please refer to 687 sched-int.h: struct sched_info: advance_target_bb. */ 688 static basic_block 689 advance_target_bb (basic_block bb, rtx_insn *insn) 690 { 691 if (insn) 692 { 693 if (BLOCK_FOR_INSN (insn) != bb 694 && control_flow_insn_p (insn) 695 /* We handle interblock movement of the speculation check 696 or over a speculation check in 697 haifa-sched.c: move_block_after_check (). */ 698 && !IS_SPECULATION_BRANCHY_CHECK_P (insn) 699 && !IS_SPECULATION_BRANCHY_CHECK_P (BB_END (bb))) 700 { 701 /* Assert that we don't move jumps across blocks. */ 702 gcc_assert (!control_flow_insn_p (BB_END (bb)) 703 && NOTE_INSN_BASIC_BLOCK_P (BB_HEAD (bb->next_bb))); 704 return bb; 705 } 706 else 707 return 0; 708 } 709 else 710 /* Return next non empty block. */ 711 { 712 do 713 { 714 gcc_assert (bb != last_bb); 715 716 bb = bb->next_bb; 717 } 718 while (bb_note (bb) == BB_END (bb)); 719 720 return bb; 721 } 722 } 723 724 /* Fix internal data after interblock movement of jump instruction. 725 For parameter meaning please refer to 726 sched-int.h: struct sched_info: fix_recovery_cfg. */ 727 static void 728 ebb_fix_recovery_cfg (int bbi ATTRIBUTE_UNUSED, int jump_bbi, 729 int jump_bb_nexti) 730 { 731 gcc_assert (last_bb->index != bbi); 732 733 if (jump_bb_nexti == last_bb->index) 734 last_bb = BASIC_BLOCK_FOR_FN (cfun, jump_bbi); 735 } 736 737 #endif /* INSN_SCHEDULING */ 738