| 1 | /* Instruction scheduling pass. |
| 2 | Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, |
| 3 | 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 |
| 4 | Free Software Foundation, Inc. |
| 5 | Contributed by Michael Tiemann (tiemann@cygnus.com) Enhanced by, |
| 6 | and currently maintained by, Jim Wilson (wilson@cygnus.com) |
| 7 | |
| 8 | This file is part of GCC. |
| 9 | |
| 10 | GCC is free software; you can redistribute it and/or modify it under |
| 11 | the terms of the GNU General Public License as published by the Free |
| 12 | Software Foundation; either version 3, or (at your option) any later |
| 13 | version. |
| 14 | |
| 15 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
| 16 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 17 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 18 | for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU General Public License |
| 21 | along with GCC; see the file COPYING3. If not see |
| 22 | <http://www.gnu.org/licenses/>. */ |
| 23 | \f |
| 24 | #include "config.h" |
| 25 | #include "system.h" |
| 26 | #include "coretypes.h" |
| 27 | #include "tm.h" |
| 28 | #include "toplev.h" |
| 29 | #include "rtl.h" |
| 30 | #include "tm_p.h" |
| 31 | #include "hard-reg-set.h" |
| 32 | #include "regs.h" |
| 33 | #include "function.h" |
| 34 | #include "flags.h" |
| 35 | #include "insn-config.h" |
| 36 | #include "insn-attr.h" |
| 37 | #include "except.h" |
| 38 | #include "toplev.h" |
| 39 | #include "recog.h" |
| 40 | #include "cfglayout.h" |
| 41 | #include "params.h" |
| 42 | #include "sched-int.h" |
| 43 | #include "target.h" |
| 44 | #include "output.h" |
| 45 | |
| 46 | \f |
| 47 | #ifdef INSN_SCHEDULING |
| 48 | |
| 49 | /* The number of insns to be scheduled in total. */ |
| 50 | static int rgn_n_insns; |
| 51 | |
| 52 | /* The number of insns scheduled so far. */ |
| 53 | static int sched_rgn_n_insns; |
| 54 | |
| 55 | /* Set of blocks, that already have their dependencies calculated. */ |
| 56 | static bitmap_head dont_calc_deps; |
| 57 | |
| 58 | /* Last basic block in current ebb. */ |
| 59 | static basic_block last_bb; |
| 60 | |
| 61 | /* Implementations of the sched_info functions for region scheduling. */ |
| 62 | static void init_ready_list (void); |
| 63 | static void begin_schedule_ready (rtx, rtx); |
| 64 | static int schedule_more_p (void); |
| 65 | static const char *ebb_print_insn (const_rtx, int); |
| 66 | static int rank (rtx, rtx); |
| 67 | static int ebb_contributes_to_priority (rtx, rtx); |
| 68 | static basic_block earliest_block_with_similiar_load (basic_block, rtx); |
| 69 | static void add_deps_for_risky_insns (rtx, rtx); |
| 70 | static basic_block schedule_ebb (rtx, rtx); |
| 71 | static void debug_ebb_dependencies (rtx, rtx); |
| 72 | |
| 73 | static void ebb_add_remove_insn (rtx, int); |
| 74 | static void ebb_add_block (basic_block, basic_block); |
| 75 | static basic_block advance_target_bb (basic_block, rtx); |
| 76 | static void ebb_fix_recovery_cfg (int, int, int); |
| 77 | |
| 78 | /* Return nonzero if there are more insns that should be scheduled. */ |
| 79 | |
| 80 | static int |
| 81 | schedule_more_p (void) |
| 82 | { |
| 83 | return sched_rgn_n_insns < rgn_n_insns; |
| 84 | } |
| 85 | |
| 86 | /* Print dependency information about ebb between HEAD and TAIL. */ |
| 87 | static void |
| 88 | debug_ebb_dependencies (rtx head, rtx tail) |
| 89 | { |
| 90 | fprintf (sched_dump, |
| 91 | ";; --------------- forward dependences: ------------ \n"); |
| 92 | |
| 93 | fprintf (sched_dump, "\n;; --- EBB Dependences --- from bb%d to bb%d \n", |
| 94 | BLOCK_NUM (head), BLOCK_NUM (tail)); |
| 95 | |
| 96 | debug_dependencies (head, tail); |
| 97 | } |
| 98 | |
| 99 | /* Add all insns that are initially ready to the ready list READY. Called |
| 100 | once before scheduling a set of insns. */ |
| 101 | |
| 102 | static void |
| 103 | init_ready_list (void) |
| 104 | { |
| 105 | int n = 0; |
| 106 | rtx prev_head = current_sched_info->prev_head; |
| 107 | rtx next_tail = current_sched_info->next_tail; |
| 108 | rtx insn; |
| 109 | |
| 110 | sched_rgn_n_insns = 0; |
| 111 | |
| 112 | /* Print debugging information. */ |
| 113 | if (sched_verbose >= 5) |
| 114 | debug_ebb_dependencies (NEXT_INSN (prev_head), PREV_INSN (next_tail)); |
| 115 | |
| 116 | /* Initialize ready list with all 'ready' insns in target block. |
| 117 | Count number of insns in the target block being scheduled. */ |
| 118 | for (insn = NEXT_INSN (prev_head); insn != next_tail; insn = NEXT_INSN (insn)) |
| 119 | { |
| 120 | try_ready (insn); |
| 121 | n++; |
| 122 | } |
| 123 | |
| 124 | gcc_assert (n == rgn_n_insns); |
| 125 | } |
| 126 | |
| 127 | /* INSN is being scheduled after LAST. Update counters. */ |
| 128 | static void |
| 129 | begin_schedule_ready (rtx insn, rtx last) |
| 130 | { |
| 131 | sched_rgn_n_insns++; |
| 132 | |
| 133 | if (BLOCK_FOR_INSN (insn) == last_bb |
| 134 | /* INSN is a jump in the last block, ... */ |
| 135 | && control_flow_insn_p (insn) |
| 136 | /* that is going to be moved over some instructions. */ |
| 137 | && last != PREV_INSN (insn)) |
| 138 | { |
| 139 | edge e; |
| 140 | edge_iterator ei; |
| 141 | basic_block bb; |
| 142 | |
| 143 | /* An obscure special case, where we do have partially dead |
| 144 | instruction scheduled after last control flow instruction. |
| 145 | In this case we can create new basic block. It is |
| 146 | always exactly one basic block last in the sequence. */ |
| 147 | |
| 148 | FOR_EACH_EDGE (e, ei, last_bb->succs) |
| 149 | if (e->flags & EDGE_FALLTHRU) |
| 150 | break; |
| 151 | |
| 152 | #ifdef ENABLE_CHECKING |
| 153 | gcc_assert (!e || !(e->flags & EDGE_COMPLEX)); |
| 154 | |
| 155 | gcc_assert (BLOCK_FOR_INSN (insn) == last_bb |
| 156 | && !IS_SPECULATION_CHECK_P (insn) |
| 157 | && BB_HEAD (last_bb) != insn |
| 158 | && BB_END (last_bb) == insn); |
| 159 | |
| 160 | { |
| 161 | rtx x; |
| 162 | |
| 163 | x = NEXT_INSN (insn); |
| 164 | if (e) |
| 165 | gcc_assert (NOTE_P (x) || LABEL_P (x)); |
| 166 | else |
| 167 | gcc_assert (BARRIER_P (x)); |
| 168 | } |
| 169 | #endif |
| 170 | |
| 171 | if (e) |
| 172 | { |
| 173 | bb = split_edge (e); |
| 174 | gcc_assert (NOTE_INSN_BASIC_BLOCK_P (BB_END (bb))); |
| 175 | } |
| 176 | else |
| 177 | /* Create an empty unreachable block after the INSN. */ |
| 178 | bb = create_basic_block (NEXT_INSN (insn), NULL_RTX, last_bb); |
| 179 | |
| 180 | /* split_edge () creates BB before E->DEST. Keep in mind, that |
| 181 | this operation extends scheduling region till the end of BB. |
| 182 | Hence, we need to shift NEXT_TAIL, so haifa-sched.c won't go out |
| 183 | of the scheduling region. */ |
| 184 | current_sched_info->next_tail = NEXT_INSN (BB_END (bb)); |
| 185 | gcc_assert (current_sched_info->next_tail); |
| 186 | |
| 187 | /* Append new basic block to the end of the ebb. */ |
| 188 | sched_init_only_bb (bb, last_bb); |
| 189 | gcc_assert (last_bb == bb); |
| 190 | } |
| 191 | } |
| 192 | |
| 193 | /* Return a string that contains the insn uid and optionally anything else |
| 194 | necessary to identify this insn in an output. It's valid to use a |
| 195 | static buffer for this. The ALIGNED parameter should cause the string |
| 196 | to be formatted so that multiple output lines will line up nicely. */ |
| 197 | |
| 198 | static const char * |
| 199 | ebb_print_insn (const_rtx insn, int aligned ATTRIBUTE_UNUSED) |
| 200 | { |
| 201 | static char tmp[80]; |
| 202 | |
| 203 | /* '+' before insn means it is a new cycle start. */ |
| 204 | if (GET_MODE (insn) == TImode) |
| 205 | sprintf (tmp, "+ %4d", INSN_UID (insn)); |
| 206 | else |
| 207 | sprintf (tmp, " %4d", INSN_UID (insn)); |
| 208 | |
| 209 | return tmp; |
| 210 | } |
| 211 | |
| 212 | /* Compare priority of two insns. Return a positive number if the second |
| 213 | insn is to be preferred for scheduling, and a negative one if the first |
| 214 | is to be preferred. Zero if they are equally good. */ |
| 215 | |
| 216 | static int |
| 217 | rank (rtx insn1, rtx insn2) |
| 218 | { |
| 219 | basic_block bb1 = BLOCK_FOR_INSN (insn1); |
| 220 | basic_block bb2 = BLOCK_FOR_INSN (insn2); |
| 221 | |
| 222 | if (bb1->count > bb2->count |
| 223 | || bb1->frequency > bb2->frequency) |
| 224 | return -1; |
| 225 | if (bb1->count < bb2->count |
| 226 | || bb1->frequency < bb2->frequency) |
| 227 | return 1; |
| 228 | return 0; |
| 229 | } |
| 230 | |
| 231 | /* NEXT is an instruction that depends on INSN (a backward dependence); |
| 232 | return nonzero if we should include this dependence in priority |
| 233 | calculations. */ |
| 234 | |
| 235 | static int |
| 236 | ebb_contributes_to_priority (rtx next ATTRIBUTE_UNUSED, |
| 237 | rtx insn ATTRIBUTE_UNUSED) |
| 238 | { |
| 239 | return 1; |
| 240 | } |
| 241 | |
| 242 | /* INSN is a JUMP_INSN, COND_SET is the set of registers that are |
| 243 | conditionally set before INSN. Store the set of registers that |
| 244 | must be considered as used by this jump in USED and that of |
| 245 | registers that must be considered as set in SET. */ |
| 246 | |
| 247 | void |
| 248 | ebb_compute_jump_reg_dependencies (rtx insn, regset cond_set, regset used, |
| 249 | regset set) |
| 250 | { |
| 251 | basic_block b = BLOCK_FOR_INSN (insn); |
| 252 | edge e; |
| 253 | edge_iterator ei; |
| 254 | |
| 255 | FOR_EACH_EDGE (e, ei, b->succs) |
| 256 | if (e->flags & EDGE_FALLTHRU) |
| 257 | /* The jump may be a by-product of a branch that has been merged |
| 258 | in the main codepath after being conditionalized. Therefore |
| 259 | it may guard the fallthrough block from using a value that has |
| 260 | conditionally overwritten that of the main codepath. So we |
| 261 | consider that it restores the value of the main codepath. */ |
| 262 | bitmap_and (set, df_get_live_in (e->dest), cond_set); |
| 263 | else |
| 264 | bitmap_ior_into (used, df_get_live_in (e->dest)); |
| 265 | } |
| 266 | |
| 267 | /* Used in schedule_insns to initialize current_sched_info for scheduling |
| 268 | regions (or single basic blocks). */ |
| 269 | |
| 270 | static struct common_sched_info_def ebb_common_sched_info; |
| 271 | |
| 272 | static struct sched_deps_info_def ebb_sched_deps_info = |
| 273 | { |
| 274 | ebb_compute_jump_reg_dependencies, |
| 275 | NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, |
| 276 | NULL, |
| 277 | 1, 0, 0 |
| 278 | }; |
| 279 | |
| 280 | static struct haifa_sched_info ebb_sched_info = |
| 281 | { |
| 282 | init_ready_list, |
| 283 | NULL, |
| 284 | schedule_more_p, |
| 285 | NULL, |
| 286 | rank, |
| 287 | ebb_print_insn, |
| 288 | ebb_contributes_to_priority, |
| 289 | |
| 290 | NULL, NULL, |
| 291 | NULL, NULL, |
| 292 | 1, 0, |
| 293 | |
| 294 | ebb_add_remove_insn, |
| 295 | begin_schedule_ready, |
| 296 | advance_target_bb, |
| 297 | SCHED_EBB |
| 298 | /* We can create new blocks in begin_schedule_ready (). */ |
| 299 | | NEW_BBS |
| 300 | }; |
| 301 | \f |
| 302 | /* Returns the earliest block in EBB currently being processed where a |
| 303 | "similar load" 'insn2' is found, and hence LOAD_INSN can move |
| 304 | speculatively into the found block. All the following must hold: |
| 305 | |
| 306 | (1) both loads have 1 base register (PFREE_CANDIDATEs). |
| 307 | (2) load_insn and load2 have a def-use dependence upon |
| 308 | the same insn 'insn1'. |
| 309 | |
| 310 | From all these we can conclude that the two loads access memory |
| 311 | addresses that differ at most by a constant, and hence if moving |
| 312 | load_insn would cause an exception, it would have been caused by |
| 313 | load2 anyhow. |
| 314 | |
| 315 | The function uses list (given by LAST_BLOCK) of already processed |
| 316 | blocks in EBB. The list is formed in `add_deps_for_risky_insns'. */ |
| 317 | |
| 318 | static basic_block |
| 319 | earliest_block_with_similiar_load (basic_block last_block, rtx load_insn) |
| 320 | { |
| 321 | sd_iterator_def back_sd_it; |
| 322 | dep_t back_dep; |
| 323 | basic_block bb, earliest_block = NULL; |
| 324 | |
| 325 | FOR_EACH_DEP (load_insn, SD_LIST_BACK, back_sd_it, back_dep) |
| 326 | { |
| 327 | rtx insn1 = DEP_PRO (back_dep); |
| 328 | |
| 329 | if (DEP_TYPE (back_dep) == REG_DEP_TRUE) |
| 330 | /* Found a DEF-USE dependence (insn1, load_insn). */ |
| 331 | { |
| 332 | sd_iterator_def fore_sd_it; |
| 333 | dep_t fore_dep; |
| 334 | |
| 335 | FOR_EACH_DEP (insn1, SD_LIST_FORW, fore_sd_it, fore_dep) |
| 336 | { |
| 337 | rtx insn2 = DEP_CON (fore_dep); |
| 338 | basic_block insn2_block = BLOCK_FOR_INSN (insn2); |
| 339 | |
| 340 | if (DEP_TYPE (fore_dep) == REG_DEP_TRUE) |
| 341 | { |
| 342 | if (earliest_block != NULL |
| 343 | && earliest_block->index < insn2_block->index) |
| 344 | continue; |
| 345 | |
| 346 | /* Found a DEF-USE dependence (insn1, insn2). */ |
| 347 | if (haifa_classify_insn (insn2) != PFREE_CANDIDATE) |
| 348 | /* insn2 not guaranteed to be a 1 base reg load. */ |
| 349 | continue; |
| 350 | |
| 351 | for (bb = last_block; bb; bb = (basic_block) bb->aux) |
| 352 | if (insn2_block == bb) |
| 353 | break; |
| 354 | |
| 355 | if (!bb) |
| 356 | /* insn2 is the similar load. */ |
| 357 | earliest_block = insn2_block; |
| 358 | } |
| 359 | } |
| 360 | } |
| 361 | } |
| 362 | |
| 363 | return earliest_block; |
| 364 | } |
| 365 | |
| 366 | /* The following function adds dependencies between jumps and risky |
| 367 | insns in given ebb. */ |
| 368 | |
| 369 | static void |
| 370 | add_deps_for_risky_insns (rtx head, rtx tail) |
| 371 | { |
| 372 | rtx insn, prev; |
| 373 | int classification; |
| 374 | rtx last_jump = NULL_RTX; |
| 375 | rtx next_tail = NEXT_INSN (tail); |
| 376 | basic_block last_block = NULL, bb; |
| 377 | |
| 378 | for (insn = head; insn != next_tail; insn = NEXT_INSN (insn)) |
| 379 | if (control_flow_insn_p (insn)) |
| 380 | { |
| 381 | bb = BLOCK_FOR_INSN (insn); |
| 382 | bb->aux = last_block; |
| 383 | last_block = bb; |
| 384 | last_jump = insn; |
| 385 | } |
| 386 | else if (INSN_P (insn) && last_jump != NULL_RTX) |
| 387 | { |
| 388 | classification = haifa_classify_insn (insn); |
| 389 | prev = last_jump; |
| 390 | switch (classification) |
| 391 | { |
| 392 | case PFREE_CANDIDATE: |
| 393 | if (flag_schedule_speculative_load) |
| 394 | { |
| 395 | bb = earliest_block_with_similiar_load (last_block, insn); |
| 396 | if (bb) |
| 397 | { |
| 398 | bb = (basic_block) bb->aux; |
| 399 | if (!bb) |
| 400 | break; |
| 401 | prev = BB_END (bb); |
| 402 | } |
| 403 | } |
| 404 | /* Fall through. */ |
| 405 | case TRAP_RISKY: |
| 406 | case IRISKY: |
| 407 | case PRISKY_CANDIDATE: |
| 408 | /* ??? We could implement better checking PRISKY_CANDIDATEs |
| 409 | analogous to sched-rgn.c. */ |
| 410 | /* We can not change the mode of the backward |
| 411 | dependency because REG_DEP_ANTI has the lowest |
| 412 | rank. */ |
| 413 | if (! sched_insns_conditions_mutex_p (insn, prev)) |
| 414 | { |
| 415 | dep_def _dep, *dep = &_dep; |
| 416 | |
| 417 | init_dep (dep, prev, insn, REG_DEP_ANTI); |
| 418 | |
| 419 | if (!(current_sched_info->flags & USE_DEPS_LIST)) |
| 420 | { |
| 421 | enum DEPS_ADJUST_RESULT res; |
| 422 | |
| 423 | res = sd_add_or_update_dep (dep, false); |
| 424 | |
| 425 | /* We can't change an existing dependency with |
| 426 | DEP_ANTI. */ |
| 427 | gcc_assert (res != DEP_CHANGED); |
| 428 | } |
| 429 | else |
| 430 | { |
| 431 | if ((current_sched_info->flags & DO_SPECULATION) |
| 432 | && (spec_info->mask & BEGIN_CONTROL)) |
| 433 | DEP_STATUS (dep) = set_dep_weak (DEP_ANTI, BEGIN_CONTROL, |
| 434 | MAX_DEP_WEAK); |
| 435 | |
| 436 | sd_add_or_update_dep (dep, false); |
| 437 | |
| 438 | /* Dep_status could have been changed. |
| 439 | No assertion here. */ |
| 440 | } |
| 441 | } |
| 442 | |
| 443 | break; |
| 444 | |
| 445 | default: |
| 446 | break; |
| 447 | } |
| 448 | } |
| 449 | /* Maintain the invariant that bb->aux is clear after use. */ |
| 450 | while (last_block) |
| 451 | { |
| 452 | bb = (basic_block) last_block->aux; |
| 453 | last_block->aux = NULL; |
| 454 | last_block = bb; |
| 455 | } |
| 456 | } |
| 457 | |
| 458 | /* Schedule a single extended basic block, defined by the boundaries HEAD |
| 459 | and TAIL. */ |
| 460 | |
| 461 | static basic_block |
| 462 | schedule_ebb (rtx head, rtx tail) |
| 463 | { |
| 464 | basic_block first_bb, target_bb; |
| 465 | struct deps tmp_deps; |
| 466 | |
| 467 | first_bb = BLOCK_FOR_INSN (head); |
| 468 | last_bb = BLOCK_FOR_INSN (tail); |
| 469 | |
| 470 | if (no_real_insns_p (head, tail)) |
| 471 | return BLOCK_FOR_INSN (tail); |
| 472 | |
| 473 | gcc_assert (INSN_P (head) && INSN_P (tail)); |
| 474 | |
| 475 | if (!bitmap_bit_p (&dont_calc_deps, first_bb->index)) |
| 476 | { |
| 477 | init_deps_global (); |
| 478 | |
| 479 | /* Compute dependencies. */ |
| 480 | init_deps (&tmp_deps, false); |
| 481 | sched_analyze (&tmp_deps, head, tail); |
| 482 | free_deps (&tmp_deps); |
| 483 | |
| 484 | add_deps_for_risky_insns (head, tail); |
| 485 | |
| 486 | if (targetm.sched.dependencies_evaluation_hook) |
| 487 | targetm.sched.dependencies_evaluation_hook (head, tail); |
| 488 | |
| 489 | finish_deps_global (); |
| 490 | } |
| 491 | else |
| 492 | /* Only recovery blocks can have their dependencies already calculated, |
| 493 | and they always are single block ebbs. */ |
| 494 | gcc_assert (first_bb == last_bb); |
| 495 | |
| 496 | /* Set priorities. */ |
| 497 | current_sched_info->sched_max_insns_priority = 0; |
| 498 | rgn_n_insns = set_priorities (head, tail); |
| 499 | current_sched_info->sched_max_insns_priority++; |
| 500 | |
| 501 | current_sched_info->prev_head = PREV_INSN (head); |
| 502 | current_sched_info->next_tail = NEXT_INSN (tail); |
| 503 | |
| 504 | remove_notes (head, tail); |
| 505 | |
| 506 | unlink_bb_notes (first_bb, last_bb); |
| 507 | |
| 508 | target_bb = first_bb; |
| 509 | |
| 510 | /* Make ready list big enough to hold all the instructions from the ebb. */ |
| 511 | sched_extend_ready_list (rgn_n_insns); |
| 512 | schedule_block (&target_bb); |
| 513 | /* Free ready list. */ |
| 514 | sched_finish_ready_list (); |
| 515 | |
| 516 | /* We might pack all instructions into fewer blocks, |
| 517 | so we may made some of them empty. Can't assert (b == last_bb). */ |
| 518 | |
| 519 | /* Sanity check: verify that all region insns were scheduled. */ |
| 520 | gcc_assert (sched_rgn_n_insns == rgn_n_insns); |
| 521 | |
| 522 | /* Free dependencies. */ |
| 523 | sched_free_deps (current_sched_info->head, current_sched_info->tail, true); |
| 524 | |
| 525 | gcc_assert (haifa_recovery_bb_ever_added_p |
| 526 | || deps_pools_are_empty_p ()); |
| 527 | |
| 528 | if (EDGE_COUNT (last_bb->preds) == 0) |
| 529 | /* LAST_BB is unreachable. */ |
| 530 | { |
| 531 | gcc_assert (first_bb != last_bb |
| 532 | && EDGE_COUNT (last_bb->succs) == 0); |
| 533 | last_bb = last_bb->prev_bb; |
| 534 | delete_basic_block (last_bb->next_bb); |
| 535 | } |
| 536 | |
| 537 | return last_bb; |
| 538 | } |
| 539 | |
| 540 | /* The one entry point in this file. */ |
| 541 | |
| 542 | void |
| 543 | schedule_ebbs (void) |
| 544 | { |
| 545 | basic_block bb; |
| 546 | int probability_cutoff; |
| 547 | rtx tail; |
| 548 | |
| 549 | if (profile_info && flag_branch_probabilities) |
| 550 | probability_cutoff = PARAM_VALUE (TRACER_MIN_BRANCH_PROBABILITY_FEEDBACK); |
| 551 | else |
| 552 | probability_cutoff = PARAM_VALUE (TRACER_MIN_BRANCH_PROBABILITY); |
| 553 | probability_cutoff = REG_BR_PROB_BASE / 100 * probability_cutoff; |
| 554 | |
| 555 | /* Taking care of this degenerate case makes the rest of |
| 556 | this code simpler. */ |
| 557 | if (n_basic_blocks == NUM_FIXED_BLOCKS) |
| 558 | return; |
| 559 | |
| 560 | /* Setup infos. */ |
| 561 | { |
| 562 | memcpy (&ebb_common_sched_info, &haifa_common_sched_info, |
| 563 | sizeof (ebb_common_sched_info)); |
| 564 | |
| 565 | ebb_common_sched_info.fix_recovery_cfg = ebb_fix_recovery_cfg; |
| 566 | ebb_common_sched_info.add_block = ebb_add_block; |
| 567 | ebb_common_sched_info.sched_pass_id = SCHED_EBB_PASS; |
| 568 | |
| 569 | common_sched_info = &ebb_common_sched_info; |
| 570 | sched_deps_info = &ebb_sched_deps_info; |
| 571 | current_sched_info = &ebb_sched_info; |
| 572 | } |
| 573 | |
| 574 | haifa_sched_init (); |
| 575 | |
| 576 | compute_bb_for_insn (); |
| 577 | |
| 578 | /* Initialize DONT_CALC_DEPS and ebb-{start, end} markers. */ |
| 579 | bitmap_initialize (&dont_calc_deps, 0); |
| 580 | bitmap_clear (&dont_calc_deps); |
| 581 | |
| 582 | /* Schedule every region in the subroutine. */ |
| 583 | FOR_EACH_BB (bb) |
| 584 | { |
| 585 | rtx head = BB_HEAD (bb); |
| 586 | |
| 587 | for (;;) |
| 588 | { |
| 589 | edge e; |
| 590 | edge_iterator ei; |
| 591 | tail = BB_END (bb); |
| 592 | if (bb->next_bb == EXIT_BLOCK_PTR |
| 593 | || LABEL_P (BB_HEAD (bb->next_bb))) |
| 594 | break; |
| 595 | FOR_EACH_EDGE (e, ei, bb->succs) |
| 596 | if ((e->flags & EDGE_FALLTHRU) != 0) |
| 597 | break; |
| 598 | if (! e) |
| 599 | break; |
| 600 | if (e->probability <= probability_cutoff) |
| 601 | break; |
| 602 | bb = bb->next_bb; |
| 603 | } |
| 604 | |
| 605 | /* Blah. We should fix the rest of the code not to get confused by |
| 606 | a note or two. */ |
| 607 | while (head != tail) |
| 608 | { |
| 609 | if (NOTE_P (head)) |
| 610 | head = NEXT_INSN (head); |
| 611 | else if (NOTE_P (tail)) |
| 612 | tail = PREV_INSN (tail); |
| 613 | else if (LABEL_P (head)) |
| 614 | head = NEXT_INSN (head); |
| 615 | else |
| 616 | break; |
| 617 | } |
| 618 | |
| 619 | bb = schedule_ebb (head, tail); |
| 620 | } |
| 621 | bitmap_clear (&dont_calc_deps); |
| 622 | |
| 623 | /* Reposition the prologue and epilogue notes in case we moved the |
| 624 | prologue/epilogue insns. */ |
| 625 | if (reload_completed) |
| 626 | reposition_prologue_and_epilogue_notes (); |
| 627 | |
| 628 | haifa_sched_finish (); |
| 629 | } |
| 630 | |
| 631 | /* INSN has been added to/removed from current ebb. */ |
| 632 | static void |
| 633 | ebb_add_remove_insn (rtx insn ATTRIBUTE_UNUSED, int remove_p) |
| 634 | { |
| 635 | if (!remove_p) |
| 636 | rgn_n_insns++; |
| 637 | else |
| 638 | rgn_n_insns--; |
| 639 | } |
| 640 | |
| 641 | /* BB was added to ebb after AFTER. */ |
| 642 | static void |
| 643 | ebb_add_block (basic_block bb, basic_block after) |
| 644 | { |
| 645 | /* Recovery blocks are always bounded by BARRIERS, |
| 646 | therefore, they always form single block EBB, |
| 647 | therefore, we can use rec->index to identify such EBBs. */ |
| 648 | if (after == EXIT_BLOCK_PTR) |
| 649 | bitmap_set_bit (&dont_calc_deps, bb->index); |
| 650 | else if (after == last_bb) |
| 651 | last_bb = bb; |
| 652 | } |
| 653 | |
| 654 | /* Return next block in ebb chain. For parameter meaning please refer to |
| 655 | sched-int.h: struct sched_info: advance_target_bb. */ |
| 656 | static basic_block |
| 657 | advance_target_bb (basic_block bb, rtx insn) |
| 658 | { |
| 659 | if (insn) |
| 660 | { |
| 661 | if (BLOCK_FOR_INSN (insn) != bb |
| 662 | && control_flow_insn_p (insn) |
| 663 | /* We handle interblock movement of the speculation check |
| 664 | or over a speculation check in |
| 665 | haifa-sched.c: move_block_after_check (). */ |
| 666 | && !IS_SPECULATION_BRANCHY_CHECK_P (insn) |
| 667 | && !IS_SPECULATION_BRANCHY_CHECK_P (BB_END (bb))) |
| 668 | { |
| 669 | /* Assert that we don't move jumps across blocks. */ |
| 670 | gcc_assert (!control_flow_insn_p (BB_END (bb)) |
| 671 | && NOTE_INSN_BASIC_BLOCK_P (BB_HEAD (bb->next_bb))); |
| 672 | return bb; |
| 673 | } |
| 674 | else |
| 675 | return 0; |
| 676 | } |
| 677 | else |
| 678 | /* Return next non empty block. */ |
| 679 | { |
| 680 | do |
| 681 | { |
| 682 | gcc_assert (bb != last_bb); |
| 683 | |
| 684 | bb = bb->next_bb; |
| 685 | } |
| 686 | while (bb_note (bb) == BB_END (bb)); |
| 687 | |
| 688 | return bb; |
| 689 | } |
| 690 | } |
| 691 | |
| 692 | /* Fix internal data after interblock movement of jump instruction. |
| 693 | For parameter meaning please refer to |
| 694 | sched-int.h: struct sched_info: fix_recovery_cfg. */ |
| 695 | static void |
| 696 | ebb_fix_recovery_cfg (int bbi ATTRIBUTE_UNUSED, int jump_bbi, |
| 697 | int jump_bb_nexti) |
| 698 | { |
| 699 | gcc_assert (last_bb->index != bbi); |
| 700 | |
| 701 | if (jump_bb_nexti == last_bb->index) |
| 702 | last_bb = BASIC_BLOCK (jump_bbi); |
| 703 | } |
| 704 | |
| 705 | #endif /* INSN_SCHEDULING */ |