| 1 | /* Register renaming for the GNU compiler. |
| 2 | Copyright (C) 2000, 2001, 2002, 2003, 2004 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 |
| 7 | under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2, or (at your option) |
| 9 | any later version. |
| 10 | |
| 11 | GCC is distributed in the hope that it will be useful, but WITHOUT |
| 12 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| 13 | or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public |
| 14 | License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with GCC; see the file COPYING. If not, write to the Free |
| 18 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA |
| 19 | 02111-1307, USA. */ |
| 20 | |
| 21 | #define REG_OK_STRICT |
| 22 | |
| 23 | #include "config.h" |
| 24 | #include "system.h" |
| 25 | #include "coretypes.h" |
| 26 | #include "tm.h" |
| 27 | #include "rtl.h" |
| 28 | #include "tm_p.h" |
| 29 | #include "insn-config.h" |
| 30 | #include "regs.h" |
| 31 | #include "hard-reg-set.h" |
| 32 | #include "basic-block.h" |
| 33 | #include "reload.h" |
| 34 | #include "output.h" |
| 35 | #include "function.h" |
| 36 | #include "recog.h" |
| 37 | #include "flags.h" |
| 38 | #include "toplev.h" |
| 39 | #include "obstack.h" |
| 40 | |
| 41 | #ifndef REG_MODE_OK_FOR_BASE_P |
| 42 | #define REG_MODE_OK_FOR_BASE_P(REGNO, MODE) REG_OK_FOR_BASE_P (REGNO) |
| 43 | #endif |
| 44 | |
| 45 | static const char *const reg_class_names[] = REG_CLASS_NAMES; |
| 46 | |
| 47 | struct du_chain |
| 48 | { |
| 49 | struct du_chain *next_chain; |
| 50 | struct du_chain *next_use; |
| 51 | |
| 52 | rtx insn; |
| 53 | rtx *loc; |
| 54 | ENUM_BITFIELD(reg_class) class : 16; |
| 55 | unsigned int need_caller_save_reg:1; |
| 56 | unsigned int earlyclobber:1; |
| 57 | }; |
| 58 | |
| 59 | enum scan_actions |
| 60 | { |
| 61 | terminate_all_read, |
| 62 | terminate_overlapping_read, |
| 63 | terminate_write, |
| 64 | terminate_dead, |
| 65 | mark_read, |
| 66 | mark_write |
| 67 | }; |
| 68 | |
| 69 | static const char * const scan_actions_name[] = |
| 70 | { |
| 71 | "terminate_all_read", |
| 72 | "terminate_overlapping_read", |
| 73 | "terminate_write", |
| 74 | "terminate_dead", |
| 75 | "mark_read", |
| 76 | "mark_write" |
| 77 | }; |
| 78 | |
| 79 | static struct obstack rename_obstack; |
| 80 | |
| 81 | static void do_replace (struct du_chain *, int); |
| 82 | static void scan_rtx_reg (rtx, rtx *, enum reg_class, |
| 83 | enum scan_actions, enum op_type, int); |
| 84 | static void scan_rtx_address (rtx, rtx *, enum reg_class, |
| 85 | enum scan_actions, enum machine_mode); |
| 86 | static void scan_rtx (rtx, rtx *, enum reg_class, enum scan_actions, |
| 87 | enum op_type, int); |
| 88 | static struct du_chain *build_def_use (basic_block); |
| 89 | static void dump_def_use_chain (struct du_chain *); |
| 90 | static void note_sets (rtx, rtx, void *); |
| 91 | static void clear_dead_regs (HARD_REG_SET *, enum machine_mode, rtx); |
| 92 | static void merge_overlapping_regs (basic_block, HARD_REG_SET *, |
| 93 | struct du_chain *); |
| 94 | |
| 95 | /* Called through note_stores from update_life. Find sets of registers, and |
| 96 | record them in *DATA (which is actually a HARD_REG_SET *). */ |
| 97 | |
| 98 | static void |
| 99 | note_sets (rtx x, rtx set ATTRIBUTE_UNUSED, void *data) |
| 100 | { |
| 101 | HARD_REG_SET *pset = (HARD_REG_SET *) data; |
| 102 | unsigned int regno; |
| 103 | int nregs; |
| 104 | |
| 105 | if (GET_CODE (x) == SUBREG) |
| 106 | x = SUBREG_REG (x); |
| 107 | if (GET_CODE (x) != REG) |
| 108 | return; |
| 109 | |
| 110 | regno = REGNO (x); |
| 111 | nregs = HARD_REGNO_NREGS (regno, GET_MODE (x)); |
| 112 | |
| 113 | /* There must not be pseudos at this point. */ |
| 114 | if (regno + nregs > FIRST_PSEUDO_REGISTER) |
| 115 | abort (); |
| 116 | |
| 117 | while (nregs-- > 0) |
| 118 | SET_HARD_REG_BIT (*pset, regno + nregs); |
| 119 | } |
| 120 | |
| 121 | /* Clear all registers from *PSET for which a note of kind KIND can be found |
| 122 | in the list NOTES. */ |
| 123 | |
| 124 | static void |
| 125 | clear_dead_regs (HARD_REG_SET *pset, enum machine_mode kind, rtx notes) |
| 126 | { |
| 127 | rtx note; |
| 128 | for (note = notes; note; note = XEXP (note, 1)) |
| 129 | if (REG_NOTE_KIND (note) == kind && REG_P (XEXP (note, 0))) |
| 130 | { |
| 131 | rtx reg = XEXP (note, 0); |
| 132 | unsigned int regno = REGNO (reg); |
| 133 | int nregs = HARD_REGNO_NREGS (regno, GET_MODE (reg)); |
| 134 | |
| 135 | /* There must not be pseudos at this point. */ |
| 136 | if (regno + nregs > FIRST_PSEUDO_REGISTER) |
| 137 | abort (); |
| 138 | |
| 139 | while (nregs-- > 0) |
| 140 | CLEAR_HARD_REG_BIT (*pset, regno + nregs); |
| 141 | } |
| 142 | } |
| 143 | |
| 144 | /* For a def-use chain CHAIN in basic block B, find which registers overlap |
| 145 | its lifetime and set the corresponding bits in *PSET. */ |
| 146 | |
| 147 | static void |
| 148 | merge_overlapping_regs (basic_block b, HARD_REG_SET *pset, |
| 149 | struct du_chain *chain) |
| 150 | { |
| 151 | struct du_chain *t = chain; |
| 152 | rtx insn; |
| 153 | HARD_REG_SET live; |
| 154 | |
| 155 | REG_SET_TO_HARD_REG_SET (live, b->global_live_at_start); |
| 156 | insn = BB_HEAD (b); |
| 157 | while (t) |
| 158 | { |
| 159 | /* Search forward until the next reference to the register to be |
| 160 | renamed. */ |
| 161 | while (insn != t->insn) |
| 162 | { |
| 163 | if (INSN_P (insn)) |
| 164 | { |
| 165 | clear_dead_regs (&live, REG_DEAD, REG_NOTES (insn)); |
| 166 | note_stores (PATTERN (insn), note_sets, (void *) &live); |
| 167 | /* Only record currently live regs if we are inside the |
| 168 | reg's live range. */ |
| 169 | if (t != chain) |
| 170 | IOR_HARD_REG_SET (*pset, live); |
| 171 | clear_dead_regs (&live, REG_UNUSED, REG_NOTES (insn)); |
| 172 | } |
| 173 | insn = NEXT_INSN (insn); |
| 174 | } |
| 175 | |
| 176 | IOR_HARD_REG_SET (*pset, live); |
| 177 | |
| 178 | /* For the last reference, also merge in all registers set in the |
| 179 | same insn. |
| 180 | @@@ We only have take earlyclobbered sets into account. */ |
| 181 | if (! t->next_use) |
| 182 | note_stores (PATTERN (insn), note_sets, (void *) pset); |
| 183 | |
| 184 | t = t->next_use; |
| 185 | } |
| 186 | } |
| 187 | |
| 188 | /* Perform register renaming on the current function. */ |
| 189 | |
| 190 | void |
| 191 | regrename_optimize (void) |
| 192 | { |
| 193 | int tick[FIRST_PSEUDO_REGISTER]; |
| 194 | int this_tick = 0; |
| 195 | basic_block bb; |
| 196 | char *first_obj; |
| 197 | |
| 198 | memset (tick, 0, sizeof tick); |
| 199 | |
| 200 | gcc_obstack_init (&rename_obstack); |
| 201 | first_obj = obstack_alloc (&rename_obstack, 0); |
| 202 | |
| 203 | FOR_EACH_BB (bb) |
| 204 | { |
| 205 | struct du_chain *all_chains = 0; |
| 206 | HARD_REG_SET unavailable; |
| 207 | HARD_REG_SET regs_seen; |
| 208 | |
| 209 | CLEAR_HARD_REG_SET (unavailable); |
| 210 | |
| 211 | if (rtl_dump_file) |
| 212 | fprintf (rtl_dump_file, "\nBasic block %d:\n", bb->index); |
| 213 | |
| 214 | all_chains = build_def_use (bb); |
| 215 | |
| 216 | if (rtl_dump_file) |
| 217 | dump_def_use_chain (all_chains); |
| 218 | |
| 219 | CLEAR_HARD_REG_SET (unavailable); |
| 220 | /* Don't clobber traceback for noreturn functions. */ |
| 221 | if (frame_pointer_needed) |
| 222 | { |
| 223 | int i; |
| 224 | |
| 225 | for (i = HARD_REGNO_NREGS (FRAME_POINTER_REGNUM, Pmode); i--;) |
| 226 | SET_HARD_REG_BIT (unavailable, FRAME_POINTER_REGNUM + i); |
| 227 | |
| 228 | #if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM |
| 229 | for (i = HARD_REGNO_NREGS (HARD_FRAME_POINTER_REGNUM, Pmode); i--;) |
| 230 | SET_HARD_REG_BIT (unavailable, HARD_FRAME_POINTER_REGNUM + i); |
| 231 | #endif |
| 232 | } |
| 233 | |
| 234 | CLEAR_HARD_REG_SET (regs_seen); |
| 235 | while (all_chains) |
| 236 | { |
| 237 | int new_reg, best_new_reg; |
| 238 | int n_uses; |
| 239 | struct du_chain *this = all_chains; |
| 240 | struct du_chain *tmp, *last; |
| 241 | HARD_REG_SET this_unavailable; |
| 242 | int reg = REGNO (*this->loc); |
| 243 | int i; |
| 244 | |
| 245 | all_chains = this->next_chain; |
| 246 | |
| 247 | best_new_reg = reg; |
| 248 | |
| 249 | #if 0 /* This just disables optimization opportunities. */ |
| 250 | /* Only rename once we've seen the reg more than once. */ |
| 251 | if (! TEST_HARD_REG_BIT (regs_seen, reg)) |
| 252 | { |
| 253 | SET_HARD_REG_BIT (regs_seen, reg); |
| 254 | continue; |
| 255 | } |
| 256 | #endif |
| 257 | |
| 258 | if (fixed_regs[reg] || global_regs[reg] |
| 259 | #if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM |
| 260 | || (frame_pointer_needed && reg == HARD_FRAME_POINTER_REGNUM) |
| 261 | #else |
| 262 | || (frame_pointer_needed && reg == FRAME_POINTER_REGNUM) |
| 263 | #endif |
| 264 | ) |
| 265 | continue; |
| 266 | |
| 267 | COPY_HARD_REG_SET (this_unavailable, unavailable); |
| 268 | |
| 269 | /* Find last entry on chain (which has the need_caller_save bit), |
| 270 | count number of uses, and narrow the set of registers we can |
| 271 | use for renaming. */ |
| 272 | n_uses = 0; |
| 273 | for (last = this; last->next_use; last = last->next_use) |
| 274 | { |
| 275 | n_uses++; |
| 276 | IOR_COMPL_HARD_REG_SET (this_unavailable, |
| 277 | reg_class_contents[last->class]); |
| 278 | } |
| 279 | if (n_uses < 1) |
| 280 | continue; |
| 281 | |
| 282 | IOR_COMPL_HARD_REG_SET (this_unavailable, |
| 283 | reg_class_contents[last->class]); |
| 284 | |
| 285 | if (this->need_caller_save_reg) |
| 286 | IOR_HARD_REG_SET (this_unavailable, call_used_reg_set); |
| 287 | |
| 288 | merge_overlapping_regs (bb, &this_unavailable, this); |
| 289 | |
| 290 | /* Now potential_regs is a reasonable approximation, let's |
| 291 | have a closer look at each register still in there. */ |
| 292 | for (new_reg = 0; new_reg < FIRST_PSEUDO_REGISTER; new_reg++) |
| 293 | { |
| 294 | int nregs = HARD_REGNO_NREGS (new_reg, GET_MODE (*this->loc)); |
| 295 | |
| 296 | for (i = nregs - 1; i >= 0; --i) |
| 297 | if (TEST_HARD_REG_BIT (this_unavailable, new_reg + i) |
| 298 | || fixed_regs[new_reg + i] |
| 299 | || global_regs[new_reg + i] |
| 300 | /* Can't use regs which aren't saved by the prologue. */ |
| 301 | || (! regs_ever_live[new_reg + i] |
| 302 | && ! call_used_regs[new_reg + i]) |
| 303 | #ifdef LEAF_REGISTERS |
| 304 | /* We can't use a non-leaf register if we're in a |
| 305 | leaf function. */ |
| 306 | || (current_function_is_leaf |
| 307 | && !LEAF_REGISTERS[new_reg + i]) |
| 308 | #endif |
| 309 | #ifdef HARD_REGNO_RENAME_OK |
| 310 | || ! HARD_REGNO_RENAME_OK (reg + i, new_reg + i) |
| 311 | #endif |
| 312 | ) |
| 313 | break; |
| 314 | if (i >= 0) |
| 315 | continue; |
| 316 | |
| 317 | /* See whether it accepts all modes that occur in |
| 318 | definition and uses. */ |
| 319 | for (tmp = this; tmp; tmp = tmp->next_use) |
| 320 | if (! HARD_REGNO_MODE_OK (new_reg, GET_MODE (*tmp->loc)) |
| 321 | || (tmp->need_caller_save_reg |
| 322 | && ! (HARD_REGNO_CALL_PART_CLOBBERED |
| 323 | (reg, GET_MODE (*tmp->loc))) |
| 324 | && (HARD_REGNO_CALL_PART_CLOBBERED |
| 325 | (new_reg, GET_MODE (*tmp->loc))))) |
| 326 | break; |
| 327 | if (! tmp) |
| 328 | { |
| 329 | if (tick[best_new_reg] > tick[new_reg]) |
| 330 | best_new_reg = new_reg; |
| 331 | } |
| 332 | } |
| 333 | |
| 334 | if (rtl_dump_file) |
| 335 | { |
| 336 | fprintf (rtl_dump_file, "Register %s in insn %d", |
| 337 | reg_names[reg], INSN_UID (last->insn)); |
| 338 | if (last->need_caller_save_reg) |
| 339 | fprintf (rtl_dump_file, " crosses a call"); |
| 340 | } |
| 341 | |
| 342 | if (best_new_reg == reg) |
| 343 | { |
| 344 | tick[reg] = ++this_tick; |
| 345 | if (rtl_dump_file) |
| 346 | fprintf (rtl_dump_file, "; no available better choice\n"); |
| 347 | continue; |
| 348 | } |
| 349 | |
| 350 | do_replace (this, best_new_reg); |
| 351 | tick[best_new_reg] = ++this_tick; |
| 352 | |
| 353 | if (rtl_dump_file) |
| 354 | fprintf (rtl_dump_file, ", renamed as %s\n", reg_names[best_new_reg]); |
| 355 | } |
| 356 | |
| 357 | obstack_free (&rename_obstack, first_obj); |
| 358 | } |
| 359 | |
| 360 | obstack_free (&rename_obstack, NULL); |
| 361 | |
| 362 | if (rtl_dump_file) |
| 363 | fputc ('\n', rtl_dump_file); |
| 364 | |
| 365 | count_or_remove_death_notes (NULL, 1); |
| 366 | update_life_info (NULL, UPDATE_LIFE_LOCAL, |
| 367 | PROP_REG_INFO | PROP_DEATH_NOTES); |
| 368 | } |
| 369 | |
| 370 | static void |
| 371 | do_replace (struct du_chain *chain, int reg) |
| 372 | { |
| 373 | while (chain) |
| 374 | { |
| 375 | unsigned int regno = ORIGINAL_REGNO (*chain->loc); |
| 376 | struct reg_attrs * attr = REG_ATTRS (*chain->loc); |
| 377 | |
| 378 | *chain->loc = gen_raw_REG (GET_MODE (*chain->loc), reg); |
| 379 | if (regno >= FIRST_PSEUDO_REGISTER) |
| 380 | ORIGINAL_REGNO (*chain->loc) = regno; |
| 381 | REG_ATTRS (*chain->loc) = attr; |
| 382 | chain = chain->next_use; |
| 383 | } |
| 384 | } |
| 385 | |
| 386 | |
| 387 | static struct du_chain *open_chains; |
| 388 | static struct du_chain *closed_chains; |
| 389 | |
| 390 | static void |
| 391 | scan_rtx_reg (rtx insn, rtx *loc, enum reg_class class, |
| 392 | enum scan_actions action, enum op_type type, int earlyclobber) |
| 393 | { |
| 394 | struct du_chain **p; |
| 395 | rtx x = *loc; |
| 396 | enum machine_mode mode = GET_MODE (x); |
| 397 | int this_regno = REGNO (x); |
| 398 | int this_nregs = HARD_REGNO_NREGS (this_regno, mode); |
| 399 | |
| 400 | if (action == mark_write) |
| 401 | { |
| 402 | if (type == OP_OUT) |
| 403 | { |
| 404 | struct du_chain *this |
| 405 | = obstack_alloc (&rename_obstack, sizeof (struct du_chain)); |
| 406 | this->next_use = 0; |
| 407 | this->next_chain = open_chains; |
| 408 | this->loc = loc; |
| 409 | this->insn = insn; |
| 410 | this->class = class; |
| 411 | this->need_caller_save_reg = 0; |
| 412 | this->earlyclobber = earlyclobber; |
| 413 | open_chains = this; |
| 414 | } |
| 415 | return; |
| 416 | } |
| 417 | |
| 418 | if ((type == OP_OUT && action != terminate_write) |
| 419 | || (type != OP_OUT && action == terminate_write)) |
| 420 | return; |
| 421 | |
| 422 | for (p = &open_chains; *p;) |
| 423 | { |
| 424 | struct du_chain *this = *p; |
| 425 | |
| 426 | /* Check if the chain has been terminated if it has then skip to |
| 427 | the next chain. |
| 428 | |
| 429 | This can happen when we've already appended the location to |
| 430 | the chain in Step 3, but are trying to hide in-out operands |
| 431 | from terminate_write in Step 5. */ |
| 432 | |
| 433 | if (*this->loc == cc0_rtx) |
| 434 | p = &this->next_chain; |
| 435 | else |
| 436 | { |
| 437 | int regno = REGNO (*this->loc); |
| 438 | int nregs = HARD_REGNO_NREGS (regno, GET_MODE (*this->loc)); |
| 439 | int exact_match = (regno == this_regno && nregs == this_nregs); |
| 440 | |
| 441 | if (regno + nregs <= this_regno |
| 442 | || this_regno + this_nregs <= regno) |
| 443 | { |
| 444 | p = &this->next_chain; |
| 445 | continue; |
| 446 | } |
| 447 | |
| 448 | if (action == mark_read) |
| 449 | { |
| 450 | if (! exact_match) |
| 451 | abort (); |
| 452 | |
| 453 | /* ??? Class NO_REGS can happen if the md file makes use of |
| 454 | EXTRA_CONSTRAINTS to match registers. Which is arguably |
| 455 | wrong, but there we are. Since we know not what this may |
| 456 | be replaced with, terminate the chain. */ |
| 457 | if (class != NO_REGS) |
| 458 | { |
| 459 | this = obstack_alloc (&rename_obstack, sizeof (struct du_chain)); |
| 460 | this->next_use = 0; |
| 461 | this->next_chain = (*p)->next_chain; |
| 462 | this->loc = loc; |
| 463 | this->insn = insn; |
| 464 | this->class = class; |
| 465 | this->need_caller_save_reg = 0; |
| 466 | while (*p) |
| 467 | p = &(*p)->next_use; |
| 468 | *p = this; |
| 469 | return; |
| 470 | } |
| 471 | } |
| 472 | |
| 473 | if (action != terminate_overlapping_read || ! exact_match) |
| 474 | { |
| 475 | struct du_chain *next = this->next_chain; |
| 476 | |
| 477 | /* Whether the terminated chain can be used for renaming |
| 478 | depends on the action and this being an exact match. |
| 479 | In either case, we remove this element from open_chains. */ |
| 480 | |
| 481 | if ((action == terminate_dead || action == terminate_write) |
| 482 | && exact_match) |
| 483 | { |
| 484 | this->next_chain = closed_chains; |
| 485 | closed_chains = this; |
| 486 | if (rtl_dump_file) |
| 487 | fprintf (rtl_dump_file, |
| 488 | "Closing chain %s at insn %d (%s)\n", |
| 489 | reg_names[REGNO (*this->loc)], INSN_UID (insn), |
| 490 | scan_actions_name[(int) action]); |
| 491 | } |
| 492 | else |
| 493 | { |
| 494 | if (rtl_dump_file) |
| 495 | fprintf (rtl_dump_file, |
| 496 | "Discarding chain %s at insn %d (%s)\n", |
| 497 | reg_names[REGNO (*this->loc)], INSN_UID (insn), |
| 498 | scan_actions_name[(int) action]); |
| 499 | } |
| 500 | *p = next; |
| 501 | } |
| 502 | else |
| 503 | p = &this->next_chain; |
| 504 | } |
| 505 | } |
| 506 | } |
| 507 | |
| 508 | /* Adapted from find_reloads_address_1. CLASS is INDEX_REG_CLASS or |
| 509 | BASE_REG_CLASS depending on how the register is being considered. */ |
| 510 | |
| 511 | static void |
| 512 | scan_rtx_address (rtx insn, rtx *loc, enum reg_class class, |
| 513 | enum scan_actions action, enum machine_mode mode) |
| 514 | { |
| 515 | rtx x = *loc; |
| 516 | RTX_CODE code = GET_CODE (x); |
| 517 | const char *fmt; |
| 518 | int i, j; |
| 519 | |
| 520 | if (action == mark_write) |
| 521 | return; |
| 522 | |
| 523 | switch (code) |
| 524 | { |
| 525 | case PLUS: |
| 526 | { |
| 527 | rtx orig_op0 = XEXP (x, 0); |
| 528 | rtx orig_op1 = XEXP (x, 1); |
| 529 | RTX_CODE code0 = GET_CODE (orig_op0); |
| 530 | RTX_CODE code1 = GET_CODE (orig_op1); |
| 531 | rtx op0 = orig_op0; |
| 532 | rtx op1 = orig_op1; |
| 533 | rtx *locI = NULL; |
| 534 | rtx *locB = NULL; |
| 535 | |
| 536 | if (GET_CODE (op0) == SUBREG) |
| 537 | { |
| 538 | op0 = SUBREG_REG (op0); |
| 539 | code0 = GET_CODE (op0); |
| 540 | } |
| 541 | |
| 542 | if (GET_CODE (op1) == SUBREG) |
| 543 | { |
| 544 | op1 = SUBREG_REG (op1); |
| 545 | code1 = GET_CODE (op1); |
| 546 | } |
| 547 | |
| 548 | if (code0 == MULT || code0 == SIGN_EXTEND || code0 == TRUNCATE |
| 549 | || code0 == ZERO_EXTEND || code1 == MEM) |
| 550 | { |
| 551 | locI = &XEXP (x, 0); |
| 552 | locB = &XEXP (x, 1); |
| 553 | } |
| 554 | else if (code1 == MULT || code1 == SIGN_EXTEND || code1 == TRUNCATE |
| 555 | || code1 == ZERO_EXTEND || code0 == MEM) |
| 556 | { |
| 557 | locI = &XEXP (x, 1); |
| 558 | locB = &XEXP (x, 0); |
| 559 | } |
| 560 | else if (code0 == CONST_INT || code0 == CONST |
| 561 | || code0 == SYMBOL_REF || code0 == LABEL_REF) |
| 562 | locB = &XEXP (x, 1); |
| 563 | else if (code1 == CONST_INT || code1 == CONST |
| 564 | || code1 == SYMBOL_REF || code1 == LABEL_REF) |
| 565 | locB = &XEXP (x, 0); |
| 566 | else if (code0 == REG && code1 == REG) |
| 567 | { |
| 568 | int index_op; |
| 569 | |
| 570 | if (REG_OK_FOR_INDEX_P (op0) |
| 571 | && REG_MODE_OK_FOR_BASE_P (op1, mode)) |
| 572 | index_op = 0; |
| 573 | else if (REG_OK_FOR_INDEX_P (op1) |
| 574 | && REG_MODE_OK_FOR_BASE_P (op0, mode)) |
| 575 | index_op = 1; |
| 576 | else if (REG_MODE_OK_FOR_BASE_P (op1, mode)) |
| 577 | index_op = 0; |
| 578 | else if (REG_MODE_OK_FOR_BASE_P (op0, mode)) |
| 579 | index_op = 1; |
| 580 | else if (REG_OK_FOR_INDEX_P (op1)) |
| 581 | index_op = 1; |
| 582 | else |
| 583 | index_op = 0; |
| 584 | |
| 585 | locI = &XEXP (x, index_op); |
| 586 | locB = &XEXP (x, !index_op); |
| 587 | } |
| 588 | else if (code0 == REG) |
| 589 | { |
| 590 | locI = &XEXP (x, 0); |
| 591 | locB = &XEXP (x, 1); |
| 592 | } |
| 593 | else if (code1 == REG) |
| 594 | { |
| 595 | locI = &XEXP (x, 1); |
| 596 | locB = &XEXP (x, 0); |
| 597 | } |
| 598 | |
| 599 | if (locI) |
| 600 | scan_rtx_address (insn, locI, INDEX_REG_CLASS, action, mode); |
| 601 | if (locB) |
| 602 | scan_rtx_address (insn, locB, MODE_BASE_REG_CLASS (mode), action, mode); |
| 603 | return; |
| 604 | } |
| 605 | |
| 606 | case POST_INC: |
| 607 | case POST_DEC: |
| 608 | case POST_MODIFY: |
| 609 | case PRE_INC: |
| 610 | case PRE_DEC: |
| 611 | case PRE_MODIFY: |
| 612 | #ifndef AUTO_INC_DEC |
| 613 | /* If the target doesn't claim to handle autoinc, this must be |
| 614 | something special, like a stack push. Kill this chain. */ |
| 615 | action = terminate_all_read; |
| 616 | #endif |
| 617 | break; |
| 618 | |
| 619 | case MEM: |
| 620 | scan_rtx_address (insn, &XEXP (x, 0), |
| 621 | MODE_BASE_REG_CLASS (GET_MODE (x)), action, |
| 622 | GET_MODE (x)); |
| 623 | return; |
| 624 | |
| 625 | case REG: |
| 626 | scan_rtx_reg (insn, loc, class, action, OP_IN, 0); |
| 627 | return; |
| 628 | |
| 629 | default: |
| 630 | break; |
| 631 | } |
| 632 | |
| 633 | fmt = GET_RTX_FORMAT (code); |
| 634 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
| 635 | { |
| 636 | if (fmt[i] == 'e') |
| 637 | scan_rtx_address (insn, &XEXP (x, i), class, action, mode); |
| 638 | else if (fmt[i] == 'E') |
| 639 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) |
| 640 | scan_rtx_address (insn, &XVECEXP (x, i, j), class, action, mode); |
| 641 | } |
| 642 | } |
| 643 | |
| 644 | static void |
| 645 | scan_rtx (rtx insn, rtx *loc, enum reg_class class, |
| 646 | enum scan_actions action, enum op_type type, int earlyclobber) |
| 647 | { |
| 648 | const char *fmt; |
| 649 | rtx x = *loc; |
| 650 | enum rtx_code code = GET_CODE (x); |
| 651 | int i, j; |
| 652 | |
| 653 | code = GET_CODE (x); |
| 654 | switch (code) |
| 655 | { |
| 656 | case CONST: |
| 657 | case CONST_INT: |
| 658 | case CONST_DOUBLE: |
| 659 | case CONST_VECTOR: |
| 660 | case SYMBOL_REF: |
| 661 | case LABEL_REF: |
| 662 | case CC0: |
| 663 | case PC: |
| 664 | return; |
| 665 | |
| 666 | case REG: |
| 667 | scan_rtx_reg (insn, loc, class, action, type, earlyclobber); |
| 668 | return; |
| 669 | |
| 670 | case MEM: |
| 671 | scan_rtx_address (insn, &XEXP (x, 0), |
| 672 | MODE_BASE_REG_CLASS (GET_MODE (x)), action, |
| 673 | GET_MODE (x)); |
| 674 | return; |
| 675 | |
| 676 | case SET: |
| 677 | scan_rtx (insn, &SET_SRC (x), class, action, OP_IN, 0); |
| 678 | scan_rtx (insn, &SET_DEST (x), class, action, |
| 679 | GET_CODE (PATTERN (insn)) == COND_EXEC ? OP_INOUT : OP_OUT, 0); |
| 680 | return; |
| 681 | |
| 682 | case STRICT_LOW_PART: |
| 683 | scan_rtx (insn, &XEXP (x, 0), class, action, OP_INOUT, earlyclobber); |
| 684 | return; |
| 685 | |
| 686 | case ZERO_EXTRACT: |
| 687 | case SIGN_EXTRACT: |
| 688 | scan_rtx (insn, &XEXP (x, 0), class, action, |
| 689 | type == OP_IN ? OP_IN : OP_INOUT, earlyclobber); |
| 690 | scan_rtx (insn, &XEXP (x, 1), class, action, OP_IN, 0); |
| 691 | scan_rtx (insn, &XEXP (x, 2), class, action, OP_IN, 0); |
| 692 | return; |
| 693 | |
| 694 | case POST_INC: |
| 695 | case PRE_INC: |
| 696 | case POST_DEC: |
| 697 | case PRE_DEC: |
| 698 | case POST_MODIFY: |
| 699 | case PRE_MODIFY: |
| 700 | /* Should only happen inside MEM. */ |
| 701 | abort (); |
| 702 | |
| 703 | case CLOBBER: |
| 704 | scan_rtx (insn, &SET_DEST (x), class, action, |
| 705 | GET_CODE (PATTERN (insn)) == COND_EXEC ? OP_INOUT : OP_OUT, 1); |
| 706 | return; |
| 707 | |
| 708 | case EXPR_LIST: |
| 709 | scan_rtx (insn, &XEXP (x, 0), class, action, type, 0); |
| 710 | if (XEXP (x, 1)) |
| 711 | scan_rtx (insn, &XEXP (x, 1), class, action, type, 0); |
| 712 | return; |
| 713 | |
| 714 | default: |
| 715 | break; |
| 716 | } |
| 717 | |
| 718 | fmt = GET_RTX_FORMAT (code); |
| 719 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
| 720 | { |
| 721 | if (fmt[i] == 'e') |
| 722 | scan_rtx (insn, &XEXP (x, i), class, action, type, 0); |
| 723 | else if (fmt[i] == 'E') |
| 724 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) |
| 725 | scan_rtx (insn, &XVECEXP (x, i, j), class, action, type, 0); |
| 726 | } |
| 727 | } |
| 728 | |
| 729 | /* Build def/use chain. */ |
| 730 | |
| 731 | static struct du_chain * |
| 732 | build_def_use (basic_block bb) |
| 733 | { |
| 734 | rtx insn; |
| 735 | |
| 736 | open_chains = closed_chains = NULL; |
| 737 | |
| 738 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
| 739 | { |
| 740 | if (INSN_P (insn)) |
| 741 | { |
| 742 | int n_ops; |
| 743 | rtx note; |
| 744 | rtx old_operands[MAX_RECOG_OPERANDS]; |
| 745 | rtx old_dups[MAX_DUP_OPERANDS]; |
| 746 | int i, icode; |
| 747 | int alt; |
| 748 | int predicated; |
| 749 | |
| 750 | /* Process the insn, determining its effect on the def-use |
| 751 | chains. We perform the following steps with the register |
| 752 | references in the insn: |
| 753 | (1) Any read that overlaps an open chain, but doesn't exactly |
| 754 | match, causes that chain to be closed. We can't deal |
| 755 | with overlaps yet. |
| 756 | (2) Any read outside an operand causes any chain it overlaps |
| 757 | with to be closed, since we can't replace it. |
| 758 | (3) Any read inside an operand is added if there's already |
| 759 | an open chain for it. |
| 760 | (4) For any REG_DEAD note we find, close open chains that |
| 761 | overlap it. |
| 762 | (5) For any write we find, close open chains that overlap it. |
| 763 | (6) For any write we find in an operand, make a new chain. |
| 764 | (7) For any REG_UNUSED, close any chains we just opened. */ |
| 765 | |
| 766 | icode = recog_memoized (insn); |
| 767 | extract_insn (insn); |
| 768 | if (! constrain_operands (1)) |
| 769 | fatal_insn_not_found (insn); |
| 770 | preprocess_constraints (); |
| 771 | alt = which_alternative; |
| 772 | n_ops = recog_data.n_operands; |
| 773 | |
| 774 | /* Simplify the code below by rewriting things to reflect |
| 775 | matching constraints. Also promote OP_OUT to OP_INOUT |
| 776 | in predicated instructions. */ |
| 777 | |
| 778 | predicated = GET_CODE (PATTERN (insn)) == COND_EXEC; |
| 779 | for (i = 0; i < n_ops; ++i) |
| 780 | { |
| 781 | int matches = recog_op_alt[i][alt].matches; |
| 782 | if (matches >= 0) |
| 783 | recog_op_alt[i][alt].class = recog_op_alt[matches][alt].class; |
| 784 | if (matches >= 0 || recog_op_alt[i][alt].matched >= 0 |
| 785 | || (predicated && recog_data.operand_type[i] == OP_OUT)) |
| 786 | recog_data.operand_type[i] = OP_INOUT; |
| 787 | } |
| 788 | |
| 789 | /* Step 1: Close chains for which we have overlapping reads. */ |
| 790 | for (i = 0; i < n_ops; i++) |
| 791 | scan_rtx (insn, recog_data.operand_loc[i], |
| 792 | NO_REGS, terminate_overlapping_read, |
| 793 | recog_data.operand_type[i], 0); |
| 794 | |
| 795 | /* Step 2: Close chains for which we have reads outside operands. |
| 796 | We do this by munging all operands into CC0, and closing |
| 797 | everything remaining. */ |
| 798 | |
| 799 | for (i = 0; i < n_ops; i++) |
| 800 | { |
| 801 | old_operands[i] = recog_data.operand[i]; |
| 802 | /* Don't squash match_operator or match_parallel here, since |
| 803 | we don't know that all of the contained registers are |
| 804 | reachable by proper operands. */ |
| 805 | if (recog_data.constraints[i][0] == '\0') |
| 806 | continue; |
| 807 | *recog_data.operand_loc[i] = cc0_rtx; |
| 808 | } |
| 809 | for (i = 0; i < recog_data.n_dups; i++) |
| 810 | { |
| 811 | int dup_num = recog_data.dup_num[i]; |
| 812 | |
| 813 | old_dups[i] = *recog_data.dup_loc[i]; |
| 814 | *recog_data.dup_loc[i] = cc0_rtx; |
| 815 | |
| 816 | /* For match_dup of match_operator or match_parallel, share |
| 817 | them, so that we don't miss changes in the dup. */ |
| 818 | if (icode >= 0 |
| 819 | && insn_data[icode].operand[dup_num].eliminable == 0) |
| 820 | old_dups[i] = recog_data.operand[dup_num]; |
| 821 | } |
| 822 | |
| 823 | scan_rtx (insn, &PATTERN (insn), NO_REGS, terminate_all_read, |
| 824 | OP_IN, 0); |
| 825 | |
| 826 | for (i = 0; i < recog_data.n_dups; i++) |
| 827 | *recog_data.dup_loc[i] = old_dups[i]; |
| 828 | for (i = 0; i < n_ops; i++) |
| 829 | *recog_data.operand_loc[i] = old_operands[i]; |
| 830 | |
| 831 | /* Step 2B: Can't rename function call argument registers. */ |
| 832 | if (GET_CODE (insn) == CALL_INSN && CALL_INSN_FUNCTION_USAGE (insn)) |
| 833 | scan_rtx (insn, &CALL_INSN_FUNCTION_USAGE (insn), |
| 834 | NO_REGS, terminate_all_read, OP_IN, 0); |
| 835 | |
| 836 | /* Step 2C: Can't rename asm operands that were originally |
| 837 | hard registers. */ |
| 838 | if (asm_noperands (PATTERN (insn)) > 0) |
| 839 | for (i = 0; i < n_ops; i++) |
| 840 | { |
| 841 | rtx *loc = recog_data.operand_loc[i]; |
| 842 | rtx op = *loc; |
| 843 | |
| 844 | if (GET_CODE (op) == REG |
| 845 | && REGNO (op) == ORIGINAL_REGNO (op) |
| 846 | && (recog_data.operand_type[i] == OP_IN |
| 847 | || recog_data.operand_type[i] == OP_INOUT)) |
| 848 | scan_rtx (insn, loc, NO_REGS, terminate_all_read, OP_IN, 0); |
| 849 | } |
| 850 | |
| 851 | /* Step 3: Append to chains for reads inside operands. */ |
| 852 | for (i = 0; i < n_ops + recog_data.n_dups; i++) |
| 853 | { |
| 854 | int opn = i < n_ops ? i : recog_data.dup_num[i - n_ops]; |
| 855 | rtx *loc = (i < n_ops |
| 856 | ? recog_data.operand_loc[opn] |
| 857 | : recog_data.dup_loc[i - n_ops]); |
| 858 | enum reg_class class = recog_op_alt[opn][alt].class; |
| 859 | enum op_type type = recog_data.operand_type[opn]; |
| 860 | |
| 861 | /* Don't scan match_operand here, since we've no reg class |
| 862 | information to pass down. Any operands that we could |
| 863 | substitute in will be represented elsewhere. */ |
| 864 | if (recog_data.constraints[opn][0] == '\0') |
| 865 | continue; |
| 866 | |
| 867 | if (recog_op_alt[opn][alt].is_address) |
| 868 | scan_rtx_address (insn, loc, class, mark_read, VOIDmode); |
| 869 | else |
| 870 | scan_rtx (insn, loc, class, mark_read, type, 0); |
| 871 | } |
| 872 | |
| 873 | /* Step 4: Close chains for registers that die here. |
| 874 | Also record updates for REG_INC notes. */ |
| 875 | for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) |
| 876 | { |
| 877 | if (REG_NOTE_KIND (note) == REG_DEAD) |
| 878 | scan_rtx (insn, &XEXP (note, 0), NO_REGS, terminate_dead, |
| 879 | OP_IN, 0); |
| 880 | else if (REG_NOTE_KIND (note) == REG_INC) |
| 881 | scan_rtx (insn, &XEXP (note, 0), ALL_REGS, mark_read, |
| 882 | OP_INOUT, 0); |
| 883 | } |
| 884 | |
| 885 | /* Step 4B: If this is a call, any chain live at this point |
| 886 | requires a caller-saved reg. */ |
| 887 | if (GET_CODE (insn) == CALL_INSN) |
| 888 | { |
| 889 | struct du_chain *p; |
| 890 | for (p = open_chains; p; p = p->next_chain) |
| 891 | p->need_caller_save_reg = 1; |
| 892 | } |
| 893 | |
| 894 | /* Step 5: Close open chains that overlap writes. Similar to |
| 895 | step 2, we hide in-out operands, since we do not want to |
| 896 | close these chains. */ |
| 897 | |
| 898 | for (i = 0; i < n_ops; i++) |
| 899 | { |
| 900 | old_operands[i] = recog_data.operand[i]; |
| 901 | if (recog_data.operand_type[i] == OP_INOUT) |
| 902 | *recog_data.operand_loc[i] = cc0_rtx; |
| 903 | } |
| 904 | for (i = 0; i < recog_data.n_dups; i++) |
| 905 | { |
| 906 | int opn = recog_data.dup_num[i]; |
| 907 | old_dups[i] = *recog_data.dup_loc[i]; |
| 908 | if (recog_data.operand_type[opn] == OP_INOUT) |
| 909 | *recog_data.dup_loc[i] = cc0_rtx; |
| 910 | } |
| 911 | |
| 912 | scan_rtx (insn, &PATTERN (insn), NO_REGS, terminate_write, OP_IN, 0); |
| 913 | |
| 914 | for (i = 0; i < recog_data.n_dups; i++) |
| 915 | *recog_data.dup_loc[i] = old_dups[i]; |
| 916 | for (i = 0; i < n_ops; i++) |
| 917 | *recog_data.operand_loc[i] = old_operands[i]; |
| 918 | |
| 919 | /* Step 6: Begin new chains for writes inside operands. */ |
| 920 | /* ??? Many targets have output constraints on the SET_DEST |
| 921 | of a call insn, which is stupid, since these are certainly |
| 922 | ABI defined hard registers. Don't change calls at all. |
| 923 | Similarly take special care for asm statement that originally |
| 924 | referenced hard registers. */ |
| 925 | if (asm_noperands (PATTERN (insn)) > 0) |
| 926 | { |
| 927 | for (i = 0; i < n_ops; i++) |
| 928 | if (recog_data.operand_type[i] == OP_OUT) |
| 929 | { |
| 930 | rtx *loc = recog_data.operand_loc[i]; |
| 931 | rtx op = *loc; |
| 932 | enum reg_class class = recog_op_alt[i][alt].class; |
| 933 | |
| 934 | if (GET_CODE (op) == REG |
| 935 | && REGNO (op) == ORIGINAL_REGNO (op)) |
| 936 | continue; |
| 937 | |
| 938 | scan_rtx (insn, loc, class, mark_write, OP_OUT, |
| 939 | recog_op_alt[i][alt].earlyclobber); |
| 940 | } |
| 941 | } |
| 942 | else if (GET_CODE (insn) != CALL_INSN) |
| 943 | for (i = 0; i < n_ops + recog_data.n_dups; i++) |
| 944 | { |
| 945 | int opn = i < n_ops ? i : recog_data.dup_num[i - n_ops]; |
| 946 | rtx *loc = (i < n_ops |
| 947 | ? recog_data.operand_loc[opn] |
| 948 | : recog_data.dup_loc[i - n_ops]); |
| 949 | enum reg_class class = recog_op_alt[opn][alt].class; |
| 950 | |
| 951 | if (recog_data.operand_type[opn] == OP_OUT) |
| 952 | scan_rtx (insn, loc, class, mark_write, OP_OUT, |
| 953 | recog_op_alt[opn][alt].earlyclobber); |
| 954 | } |
| 955 | |
| 956 | /* Step 7: Close chains for registers that were never |
| 957 | really used here. */ |
| 958 | for (note = REG_NOTES (insn); note; note = XEXP (note, 1)) |
| 959 | if (REG_NOTE_KIND (note) == REG_UNUSED) |
| 960 | scan_rtx (insn, &XEXP (note, 0), NO_REGS, terminate_dead, |
| 961 | OP_IN, 0); |
| 962 | } |
| 963 | if (insn == BB_END (bb)) |
| 964 | break; |
| 965 | } |
| 966 | |
| 967 | /* Since we close every chain when we find a REG_DEAD note, anything that |
| 968 | is still open lives past the basic block, so it can't be renamed. */ |
| 969 | return closed_chains; |
| 970 | } |
| 971 | |
| 972 | /* Dump all def/use chains in CHAINS to RTL_DUMP_FILE. They are |
| 973 | printed in reverse order as that's how we build them. */ |
| 974 | |
| 975 | static void |
| 976 | dump_def_use_chain (struct du_chain *chains) |
| 977 | { |
| 978 | while (chains) |
| 979 | { |
| 980 | struct du_chain *this = chains; |
| 981 | int r = REGNO (*this->loc); |
| 982 | int nregs = HARD_REGNO_NREGS (r, GET_MODE (*this->loc)); |
| 983 | fprintf (rtl_dump_file, "Register %s (%d):", reg_names[r], nregs); |
| 984 | while (this) |
| 985 | { |
| 986 | fprintf (rtl_dump_file, " %d [%s]", INSN_UID (this->insn), |
| 987 | reg_class_names[this->class]); |
| 988 | this = this->next_use; |
| 989 | } |
| 990 | fprintf (rtl_dump_file, "\n"); |
| 991 | chains = chains->next_chain; |
| 992 | } |
| 993 | } |
| 994 | \f |
| 995 | /* The following code does forward propagation of hard register copies. |
| 996 | The object is to eliminate as many dependencies as possible, so that |
| 997 | we have the most scheduling freedom. As a side effect, we also clean |
| 998 | up some silly register allocation decisions made by reload. This |
| 999 | code may be obsoleted by a new register allocator. */ |
| 1000 | |
| 1001 | /* For each register, we have a list of registers that contain the same |
| 1002 | value. The OLDEST_REGNO field points to the head of the list, and |
| 1003 | the NEXT_REGNO field runs through the list. The MODE field indicates |
| 1004 | what mode the data is known to be in; this field is VOIDmode when the |
| 1005 | register is not known to contain valid data. */ |
| 1006 | |
| 1007 | struct value_data_entry |
| 1008 | { |
| 1009 | enum machine_mode mode; |
| 1010 | unsigned int oldest_regno; |
| 1011 | unsigned int next_regno; |
| 1012 | }; |
| 1013 | |
| 1014 | struct value_data |
| 1015 | { |
| 1016 | struct value_data_entry e[FIRST_PSEUDO_REGISTER]; |
| 1017 | unsigned int max_value_regs; |
| 1018 | }; |
| 1019 | |
| 1020 | static void kill_value_regno (unsigned, struct value_data *); |
| 1021 | static void kill_value (rtx, struct value_data *); |
| 1022 | static void set_value_regno (unsigned, enum machine_mode, struct value_data *); |
| 1023 | static void init_value_data (struct value_data *); |
| 1024 | static void kill_clobbered_value (rtx, rtx, void *); |
| 1025 | static void kill_set_value (rtx, rtx, void *); |
| 1026 | static int kill_autoinc_value (rtx *, void *); |
| 1027 | static void copy_value (rtx, rtx, struct value_data *); |
| 1028 | static bool mode_change_ok (enum machine_mode, enum machine_mode, |
| 1029 | unsigned int); |
| 1030 | static rtx maybe_mode_change (enum machine_mode, enum machine_mode, |
| 1031 | enum machine_mode, unsigned int, unsigned int); |
| 1032 | static rtx find_oldest_value_reg (enum reg_class, rtx, struct value_data *); |
| 1033 | static bool replace_oldest_value_reg (rtx *, enum reg_class, rtx, |
| 1034 | struct value_data *); |
| 1035 | static bool replace_oldest_value_addr (rtx *, enum reg_class, |
| 1036 | enum machine_mode, rtx, |
| 1037 | struct value_data *); |
| 1038 | static bool replace_oldest_value_mem (rtx, rtx, struct value_data *); |
| 1039 | static bool copyprop_hardreg_forward_1 (basic_block, struct value_data *); |
| 1040 | extern void debug_value_data (struct value_data *); |
| 1041 | #ifdef ENABLE_CHECKING |
| 1042 | static void validate_value_data (struct value_data *); |
| 1043 | #endif |
| 1044 | |
| 1045 | /* Kill register REGNO. This involves removing it from any value lists, |
| 1046 | and resetting the value mode to VOIDmode. */ |
| 1047 | |
| 1048 | static void |
| 1049 | kill_value_regno (unsigned int regno, struct value_data *vd) |
| 1050 | { |
| 1051 | unsigned int i, next; |
| 1052 | |
| 1053 | if (vd->e[regno].oldest_regno != regno) |
| 1054 | { |
| 1055 | for (i = vd->e[regno].oldest_regno; |
| 1056 | vd->e[i].next_regno != regno; |
| 1057 | i = vd->e[i].next_regno) |
| 1058 | continue; |
| 1059 | vd->e[i].next_regno = vd->e[regno].next_regno; |
| 1060 | } |
| 1061 | else if ((next = vd->e[regno].next_regno) != INVALID_REGNUM) |
| 1062 | { |
| 1063 | for (i = next; i != INVALID_REGNUM; i = vd->e[i].next_regno) |
| 1064 | vd->e[i].oldest_regno = next; |
| 1065 | } |
| 1066 | |
| 1067 | vd->e[regno].mode = VOIDmode; |
| 1068 | vd->e[regno].oldest_regno = regno; |
| 1069 | vd->e[regno].next_regno = INVALID_REGNUM; |
| 1070 | |
| 1071 | #ifdef ENABLE_CHECKING |
| 1072 | validate_value_data (vd); |
| 1073 | #endif |
| 1074 | } |
| 1075 | |
| 1076 | /* Kill X. This is a convenience function for kill_value_regno |
| 1077 | so that we mind the mode the register is in. */ |
| 1078 | |
| 1079 | static void |
| 1080 | kill_value (rtx x, struct value_data *vd) |
| 1081 | { |
| 1082 | /* SUBREGS are supposed to have been eliminated by now. But some |
| 1083 | ports, e.g. i386 sse, use them to smuggle vector type information |
| 1084 | through to instruction selection. Each such SUBREG should simplify, |
| 1085 | so if we get a NULL we've done something wrong elsewhere. */ |
| 1086 | |
| 1087 | if (GET_CODE (x) == SUBREG) |
| 1088 | x = simplify_subreg (GET_MODE (x), SUBREG_REG (x), |
| 1089 | GET_MODE (SUBREG_REG (x)), SUBREG_BYTE (x)); |
| 1090 | if (REG_P (x)) |
| 1091 | { |
| 1092 | unsigned int regno = REGNO (x); |
| 1093 | unsigned int n = HARD_REGNO_NREGS (regno, GET_MODE (x)); |
| 1094 | unsigned int i, j; |
| 1095 | |
| 1096 | /* Kill the value we're told to kill. */ |
| 1097 | for (i = 0; i < n; ++i) |
| 1098 | kill_value_regno (regno + i, vd); |
| 1099 | |
| 1100 | /* Kill everything that overlapped what we're told to kill. */ |
| 1101 | if (regno < vd->max_value_regs) |
| 1102 | j = 0; |
| 1103 | else |
| 1104 | j = regno - vd->max_value_regs; |
| 1105 | for (; j < regno; ++j) |
| 1106 | { |
| 1107 | if (vd->e[j].mode == VOIDmode) |
| 1108 | continue; |
| 1109 | n = HARD_REGNO_NREGS (j, vd->e[j].mode); |
| 1110 | if (j + n > regno) |
| 1111 | for (i = 0; i < n; ++i) |
| 1112 | kill_value_regno (j + i, vd); |
| 1113 | } |
| 1114 | } |
| 1115 | } |
| 1116 | |
| 1117 | /* Remember that REGNO is valid in MODE. */ |
| 1118 | |
| 1119 | static void |
| 1120 | set_value_regno (unsigned int regno, enum machine_mode mode, |
| 1121 | struct value_data *vd) |
| 1122 | { |
| 1123 | unsigned int nregs; |
| 1124 | |
| 1125 | vd->e[regno].mode = mode; |
| 1126 | |
| 1127 | nregs = HARD_REGNO_NREGS (regno, mode); |
| 1128 | if (nregs > vd->max_value_regs) |
| 1129 | vd->max_value_regs = nregs; |
| 1130 | } |
| 1131 | |
| 1132 | /* Initialize VD such that there are no known relationships between regs. */ |
| 1133 | |
| 1134 | static void |
| 1135 | init_value_data (struct value_data *vd) |
| 1136 | { |
| 1137 | int i; |
| 1138 | for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i) |
| 1139 | { |
| 1140 | vd->e[i].mode = VOIDmode; |
| 1141 | vd->e[i].oldest_regno = i; |
| 1142 | vd->e[i].next_regno = INVALID_REGNUM; |
| 1143 | } |
| 1144 | vd->max_value_regs = 0; |
| 1145 | } |
| 1146 | |
| 1147 | /* Called through note_stores. If X is clobbered, kill its value. */ |
| 1148 | |
| 1149 | static void |
| 1150 | kill_clobbered_value (rtx x, rtx set, void *data) |
| 1151 | { |
| 1152 | struct value_data *vd = data; |
| 1153 | if (GET_CODE (set) == CLOBBER) |
| 1154 | kill_value (x, vd); |
| 1155 | } |
| 1156 | |
| 1157 | /* Called through note_stores. If X is set, not clobbered, kill its |
| 1158 | current value and install it as the root of its own value list. */ |
| 1159 | |
| 1160 | static void |
| 1161 | kill_set_value (rtx x, rtx set, void *data) |
| 1162 | { |
| 1163 | struct value_data *vd = data; |
| 1164 | if (GET_CODE (set) != CLOBBER) |
| 1165 | { |
| 1166 | kill_value (x, vd); |
| 1167 | if (REG_P (x)) |
| 1168 | set_value_regno (REGNO (x), GET_MODE (x), vd); |
| 1169 | } |
| 1170 | } |
| 1171 | |
| 1172 | /* Called through for_each_rtx. Kill any register used as the base of an |
| 1173 | auto-increment expression, and install that register as the root of its |
| 1174 | own value list. */ |
| 1175 | |
| 1176 | static int |
| 1177 | kill_autoinc_value (rtx *px, void *data) |
| 1178 | { |
| 1179 | rtx x = *px; |
| 1180 | struct value_data *vd = data; |
| 1181 | |
| 1182 | if (GET_RTX_CLASS (GET_CODE (x)) == 'a') |
| 1183 | { |
| 1184 | x = XEXP (x, 0); |
| 1185 | kill_value (x, vd); |
| 1186 | set_value_regno (REGNO (x), Pmode, vd); |
| 1187 | return -1; |
| 1188 | } |
| 1189 | |
| 1190 | return 0; |
| 1191 | } |
| 1192 | |
| 1193 | /* Assert that SRC has been copied to DEST. Adjust the data structures |
| 1194 | to reflect that SRC contains an older copy of the shared value. */ |
| 1195 | |
| 1196 | static void |
| 1197 | copy_value (rtx dest, rtx src, struct value_data *vd) |
| 1198 | { |
| 1199 | unsigned int dr = REGNO (dest); |
| 1200 | unsigned int sr = REGNO (src); |
| 1201 | unsigned int dn, sn; |
| 1202 | unsigned int i; |
| 1203 | |
| 1204 | /* ??? At present, it's possible to see noop sets. It'd be nice if |
| 1205 | this were cleaned up beforehand... */ |
| 1206 | if (sr == dr) |
| 1207 | return; |
| 1208 | |
| 1209 | /* Do not propagate copies to the stack pointer, as that can leave |
| 1210 | memory accesses with no scheduling dependency on the stack update. */ |
| 1211 | if (dr == STACK_POINTER_REGNUM) |
| 1212 | return; |
| 1213 | |
| 1214 | /* Likewise with the frame pointer, if we're using one. */ |
| 1215 | if (frame_pointer_needed && dr == HARD_FRAME_POINTER_REGNUM) |
| 1216 | return; |
| 1217 | |
| 1218 | /* If SRC and DEST overlap, don't record anything. */ |
| 1219 | dn = HARD_REGNO_NREGS (dr, GET_MODE (dest)); |
| 1220 | sn = HARD_REGNO_NREGS (sr, GET_MODE (dest)); |
| 1221 | if ((dr > sr && dr < sr + sn) |
| 1222 | || (sr > dr && sr < dr + dn)) |
| 1223 | return; |
| 1224 | |
| 1225 | /* If SRC had no assigned mode (i.e. we didn't know it was live) |
| 1226 | assign it now and assume the value came from an input argument |
| 1227 | or somesuch. */ |
| 1228 | if (vd->e[sr].mode == VOIDmode) |
| 1229 | set_value_regno (sr, vd->e[dr].mode, vd); |
| 1230 | |
| 1231 | /* If we are narrowing the input to a smaller number of hard regs, |
| 1232 | and it is in big endian, we are really extracting a high part. |
| 1233 | Since we generally associate a low part of a value with the value itself, |
| 1234 | we must not do the same for the high part. |
| 1235 | Note we can still get low parts for the same mode combination through |
| 1236 | a two-step copy involving differently sized hard regs. |
| 1237 | Assume hard regs fr* are 32 bits bits each, while r* are 64 bits each: |
| 1238 | (set (reg:DI r0) (reg:DI fr0)) |
| 1239 | (set (reg:SI fr2) (reg:SI r0)) |
| 1240 | loads the low part of (reg:DI fr0) - i.e. fr1 - into fr2, while: |
| 1241 | (set (reg:SI fr2) (reg:SI fr0)) |
| 1242 | loads the high part of (reg:DI fr0) into fr2. |
| 1243 | |
| 1244 | We can't properly represent the latter case in our tables, so don't |
| 1245 | record anything then. */ |
| 1246 | else if (sn < (unsigned int) HARD_REGNO_NREGS (sr, vd->e[sr].mode) |
| 1247 | && (GET_MODE_SIZE (vd->e[sr].mode) > UNITS_PER_WORD |
| 1248 | ? WORDS_BIG_ENDIAN : BYTES_BIG_ENDIAN)) |
| 1249 | return; |
| 1250 | |
| 1251 | /* If SRC had been assigned a mode narrower than the copy, we can't |
| 1252 | link DEST into the chain, because not all of the pieces of the |
| 1253 | copy came from oldest_regno. */ |
| 1254 | else if (sn > (unsigned int) HARD_REGNO_NREGS (sr, vd->e[sr].mode)) |
| 1255 | return; |
| 1256 | |
| 1257 | /* Link DR at the end of the value chain used by SR. */ |
| 1258 | |
| 1259 | vd->e[dr].oldest_regno = vd->e[sr].oldest_regno; |
| 1260 | |
| 1261 | for (i = sr; vd->e[i].next_regno != INVALID_REGNUM; i = vd->e[i].next_regno) |
| 1262 | continue; |
| 1263 | vd->e[i].next_regno = dr; |
| 1264 | |
| 1265 | #ifdef ENABLE_CHECKING |
| 1266 | validate_value_data (vd); |
| 1267 | #endif |
| 1268 | } |
| 1269 | |
| 1270 | /* Return true if a mode change from ORIG to NEW is allowed for REGNO. */ |
| 1271 | |
| 1272 | static bool |
| 1273 | mode_change_ok (enum machine_mode orig_mode, enum machine_mode new_mode, |
| 1274 | unsigned int regno ATTRIBUTE_UNUSED) |
| 1275 | { |
| 1276 | if (GET_MODE_SIZE (orig_mode) < GET_MODE_SIZE (new_mode)) |
| 1277 | return false; |
| 1278 | |
| 1279 | #ifdef CANNOT_CHANGE_MODE_CLASS |
| 1280 | return !REG_CANNOT_CHANGE_MODE_P (regno, orig_mode, new_mode); |
| 1281 | #endif |
| 1282 | |
| 1283 | return true; |
| 1284 | } |
| 1285 | |
| 1286 | /* Register REGNO was originally set in ORIG_MODE. It - or a copy of it - |
| 1287 | was copied in COPY_MODE to COPY_REGNO, and then COPY_REGNO was accessed |
| 1288 | in NEW_MODE. |
| 1289 | Return a NEW_MODE rtx for REGNO if that's OK, otherwise return NULL_RTX. */ |
| 1290 | |
| 1291 | static rtx |
| 1292 | maybe_mode_change (enum machine_mode orig_mode, enum machine_mode copy_mode, |
| 1293 | enum machine_mode new_mode, unsigned int regno, |
| 1294 | unsigned int copy_regno ATTRIBUTE_UNUSED) |
| 1295 | { |
| 1296 | if (orig_mode == new_mode) |
| 1297 | return gen_rtx_raw_REG (new_mode, regno); |
| 1298 | else if (mode_change_ok (orig_mode, new_mode, regno)) |
| 1299 | { |
| 1300 | int copy_nregs = HARD_REGNO_NREGS (copy_regno, copy_mode); |
| 1301 | int use_nregs = HARD_REGNO_NREGS (copy_regno, new_mode); |
| 1302 | int copy_offset |
| 1303 | = GET_MODE_SIZE (copy_mode) / copy_nregs * (copy_nregs - use_nregs); |
| 1304 | int offset |
| 1305 | = GET_MODE_SIZE (orig_mode) - GET_MODE_SIZE (new_mode) - copy_offset; |
| 1306 | int byteoffset = offset % UNITS_PER_WORD; |
| 1307 | int wordoffset = offset - byteoffset; |
| 1308 | |
| 1309 | offset = ((WORDS_BIG_ENDIAN ? wordoffset : 0) |
| 1310 | + (BYTES_BIG_ENDIAN ? byteoffset : 0)); |
| 1311 | return gen_rtx_raw_REG (new_mode, |
| 1312 | regno + subreg_regno_offset (regno, orig_mode, |
| 1313 | offset, |
| 1314 | new_mode)); |
| 1315 | } |
| 1316 | return NULL_RTX; |
| 1317 | } |
| 1318 | |
| 1319 | /* Find the oldest copy of the value contained in REGNO that is in |
| 1320 | register class CLASS and has mode MODE. If found, return an rtx |
| 1321 | of that oldest register, otherwise return NULL. */ |
| 1322 | |
| 1323 | static rtx |
| 1324 | find_oldest_value_reg (enum reg_class class, rtx reg, struct value_data *vd) |
| 1325 | { |
| 1326 | unsigned int regno = REGNO (reg); |
| 1327 | enum machine_mode mode = GET_MODE (reg); |
| 1328 | unsigned int i; |
| 1329 | |
| 1330 | /* If we are accessing REG in some mode other that what we set it in, |
| 1331 | make sure that the replacement is valid. In particular, consider |
| 1332 | (set (reg:DI r11) (...)) |
| 1333 | (set (reg:SI r9) (reg:SI r11)) |
| 1334 | (set (reg:SI r10) (...)) |
| 1335 | (set (...) (reg:DI r9)) |
| 1336 | Replacing r9 with r11 is invalid. */ |
| 1337 | if (mode != vd->e[regno].mode) |
| 1338 | { |
| 1339 | if (HARD_REGNO_NREGS (regno, mode) |
| 1340 | > HARD_REGNO_NREGS (regno, vd->e[regno].mode)) |
| 1341 | return NULL_RTX; |
| 1342 | } |
| 1343 | |
| 1344 | for (i = vd->e[regno].oldest_regno; i != regno; i = vd->e[i].next_regno) |
| 1345 | { |
| 1346 | enum machine_mode oldmode = vd->e[i].mode; |
| 1347 | rtx new; |
| 1348 | unsigned int last; |
| 1349 | |
| 1350 | for (last = i; last < i + HARD_REGNO_NREGS (i, mode); last++) |
| 1351 | if (!TEST_HARD_REG_BIT (reg_class_contents[class], last)) |
| 1352 | return NULL_RTX; |
| 1353 | |
| 1354 | new = maybe_mode_change (oldmode, vd->e[regno].mode, mode, i, regno); |
| 1355 | if (new) |
| 1356 | { |
| 1357 | ORIGINAL_REGNO (new) = ORIGINAL_REGNO (reg); |
| 1358 | REG_ATTRS (new) = REG_ATTRS (reg); |
| 1359 | return new; |
| 1360 | } |
| 1361 | } |
| 1362 | |
| 1363 | return NULL_RTX; |
| 1364 | } |
| 1365 | |
| 1366 | /* If possible, replace the register at *LOC with the oldest register |
| 1367 | in register class CLASS. Return true if successfully replaced. */ |
| 1368 | |
| 1369 | static bool |
| 1370 | replace_oldest_value_reg (rtx *loc, enum reg_class class, rtx insn, |
| 1371 | struct value_data *vd) |
| 1372 | { |
| 1373 | rtx new = find_oldest_value_reg (class, *loc, vd); |
| 1374 | if (new) |
| 1375 | { |
| 1376 | if (rtl_dump_file) |
| 1377 | fprintf (rtl_dump_file, "insn %u: replaced reg %u with %u\n", |
| 1378 | INSN_UID (insn), REGNO (*loc), REGNO (new)); |
| 1379 | |
| 1380 | *loc = new; |
| 1381 | return true; |
| 1382 | } |
| 1383 | return false; |
| 1384 | } |
| 1385 | |
| 1386 | /* Similar to replace_oldest_value_reg, but *LOC contains an address. |
| 1387 | Adapted from find_reloads_address_1. CLASS is INDEX_REG_CLASS or |
| 1388 | BASE_REG_CLASS depending on how the register is being considered. */ |
| 1389 | |
| 1390 | static bool |
| 1391 | replace_oldest_value_addr (rtx *loc, enum reg_class class, |
| 1392 | enum machine_mode mode, rtx insn, |
| 1393 | struct value_data *vd) |
| 1394 | { |
| 1395 | rtx x = *loc; |
| 1396 | RTX_CODE code = GET_CODE (x); |
| 1397 | const char *fmt; |
| 1398 | int i, j; |
| 1399 | bool changed = false; |
| 1400 | |
| 1401 | switch (code) |
| 1402 | { |
| 1403 | case PLUS: |
| 1404 | { |
| 1405 | rtx orig_op0 = XEXP (x, 0); |
| 1406 | rtx orig_op1 = XEXP (x, 1); |
| 1407 | RTX_CODE code0 = GET_CODE (orig_op0); |
| 1408 | RTX_CODE code1 = GET_CODE (orig_op1); |
| 1409 | rtx op0 = orig_op0; |
| 1410 | rtx op1 = orig_op1; |
| 1411 | rtx *locI = NULL; |
| 1412 | rtx *locB = NULL; |
| 1413 | |
| 1414 | if (GET_CODE (op0) == SUBREG) |
| 1415 | { |
| 1416 | op0 = SUBREG_REG (op0); |
| 1417 | code0 = GET_CODE (op0); |
| 1418 | } |
| 1419 | |
| 1420 | if (GET_CODE (op1) == SUBREG) |
| 1421 | { |
| 1422 | op1 = SUBREG_REG (op1); |
| 1423 | code1 = GET_CODE (op1); |
| 1424 | } |
| 1425 | |
| 1426 | if (code0 == MULT || code0 == SIGN_EXTEND || code0 == TRUNCATE |
| 1427 | || code0 == ZERO_EXTEND || code1 == MEM) |
| 1428 | { |
| 1429 | locI = &XEXP (x, 0); |
| 1430 | locB = &XEXP (x, 1); |
| 1431 | } |
| 1432 | else if (code1 == MULT || code1 == SIGN_EXTEND || code1 == TRUNCATE |
| 1433 | || code1 == ZERO_EXTEND || code0 == MEM) |
| 1434 | { |
| 1435 | locI = &XEXP (x, 1); |
| 1436 | locB = &XEXP (x, 0); |
| 1437 | } |
| 1438 | else if (code0 == CONST_INT || code0 == CONST |
| 1439 | || code0 == SYMBOL_REF || code0 == LABEL_REF) |
| 1440 | locB = &XEXP (x, 1); |
| 1441 | else if (code1 == CONST_INT || code1 == CONST |
| 1442 | || code1 == SYMBOL_REF || code1 == LABEL_REF) |
| 1443 | locB = &XEXP (x, 0); |
| 1444 | else if (code0 == REG && code1 == REG) |
| 1445 | { |
| 1446 | int index_op; |
| 1447 | |
| 1448 | if (REG_OK_FOR_INDEX_P (op0) |
| 1449 | && REG_MODE_OK_FOR_BASE_P (op1, mode)) |
| 1450 | index_op = 0; |
| 1451 | else if (REG_OK_FOR_INDEX_P (op1) |
| 1452 | && REG_MODE_OK_FOR_BASE_P (op0, mode)) |
| 1453 | index_op = 1; |
| 1454 | else if (REG_MODE_OK_FOR_BASE_P (op1, mode)) |
| 1455 | index_op = 0; |
| 1456 | else if (REG_MODE_OK_FOR_BASE_P (op0, mode)) |
| 1457 | index_op = 1; |
| 1458 | else if (REG_OK_FOR_INDEX_P (op1)) |
| 1459 | index_op = 1; |
| 1460 | else |
| 1461 | index_op = 0; |
| 1462 | |
| 1463 | locI = &XEXP (x, index_op); |
| 1464 | locB = &XEXP (x, !index_op); |
| 1465 | } |
| 1466 | else if (code0 == REG) |
| 1467 | { |
| 1468 | locI = &XEXP (x, 0); |
| 1469 | locB = &XEXP (x, 1); |
| 1470 | } |
| 1471 | else if (code1 == REG) |
| 1472 | { |
| 1473 | locI = &XEXP (x, 1); |
| 1474 | locB = &XEXP (x, 0); |
| 1475 | } |
| 1476 | |
| 1477 | if (locI) |
| 1478 | changed |= replace_oldest_value_addr (locI, INDEX_REG_CLASS, mode, |
| 1479 | insn, vd); |
| 1480 | if (locB) |
| 1481 | changed |= replace_oldest_value_addr (locB, |
| 1482 | MODE_BASE_REG_CLASS (mode), |
| 1483 | mode, insn, vd); |
| 1484 | return changed; |
| 1485 | } |
| 1486 | |
| 1487 | case POST_INC: |
| 1488 | case POST_DEC: |
| 1489 | case POST_MODIFY: |
| 1490 | case PRE_INC: |
| 1491 | case PRE_DEC: |
| 1492 | case PRE_MODIFY: |
| 1493 | return false; |
| 1494 | |
| 1495 | case MEM: |
| 1496 | return replace_oldest_value_mem (x, insn, vd); |
| 1497 | |
| 1498 | case REG: |
| 1499 | return replace_oldest_value_reg (loc, class, insn, vd); |
| 1500 | |
| 1501 | default: |
| 1502 | break; |
| 1503 | } |
| 1504 | |
| 1505 | fmt = GET_RTX_FORMAT (code); |
| 1506 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
| 1507 | { |
| 1508 | if (fmt[i] == 'e') |
| 1509 | changed |= replace_oldest_value_addr (&XEXP (x, i), class, mode, |
| 1510 | insn, vd); |
| 1511 | else if (fmt[i] == 'E') |
| 1512 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) |
| 1513 | changed |= replace_oldest_value_addr (&XVECEXP (x, i, j), class, |
| 1514 | mode, insn, vd); |
| 1515 | } |
| 1516 | |
| 1517 | return changed; |
| 1518 | } |
| 1519 | |
| 1520 | /* Similar to replace_oldest_value_reg, but X contains a memory. */ |
| 1521 | |
| 1522 | static bool |
| 1523 | replace_oldest_value_mem (rtx x, rtx insn, struct value_data *vd) |
| 1524 | { |
| 1525 | return replace_oldest_value_addr (&XEXP (x, 0), |
| 1526 | MODE_BASE_REG_CLASS (GET_MODE (x)), |
| 1527 | GET_MODE (x), insn, vd); |
| 1528 | } |
| 1529 | |
| 1530 | /* Perform the forward copy propagation on basic block BB. */ |
| 1531 | |
| 1532 | static bool |
| 1533 | copyprop_hardreg_forward_1 (basic_block bb, struct value_data *vd) |
| 1534 | { |
| 1535 | bool changed = false; |
| 1536 | rtx insn; |
| 1537 | |
| 1538 | for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn)) |
| 1539 | { |
| 1540 | int n_ops, i, alt, predicated; |
| 1541 | bool is_asm; |
| 1542 | rtx set; |
| 1543 | |
| 1544 | if (! INSN_P (insn)) |
| 1545 | { |
| 1546 | if (insn == BB_END (bb)) |
| 1547 | break; |
| 1548 | else |
| 1549 | continue; |
| 1550 | } |
| 1551 | |
| 1552 | set = single_set (insn); |
| 1553 | extract_insn (insn); |
| 1554 | if (! constrain_operands (1)) |
| 1555 | fatal_insn_not_found (insn); |
| 1556 | preprocess_constraints (); |
| 1557 | alt = which_alternative; |
| 1558 | n_ops = recog_data.n_operands; |
| 1559 | is_asm = asm_noperands (PATTERN (insn)) >= 0; |
| 1560 | |
| 1561 | /* Simplify the code below by rewriting things to reflect |
| 1562 | matching constraints. Also promote OP_OUT to OP_INOUT |
| 1563 | in predicated instructions. */ |
| 1564 | |
| 1565 | predicated = GET_CODE (PATTERN (insn)) == COND_EXEC; |
| 1566 | for (i = 0; i < n_ops; ++i) |
| 1567 | { |
| 1568 | int matches = recog_op_alt[i][alt].matches; |
| 1569 | if (matches >= 0) |
| 1570 | recog_op_alt[i][alt].class = recog_op_alt[matches][alt].class; |
| 1571 | if (matches >= 0 || recog_op_alt[i][alt].matched >= 0 |
| 1572 | || (predicated && recog_data.operand_type[i] == OP_OUT)) |
| 1573 | recog_data.operand_type[i] = OP_INOUT; |
| 1574 | } |
| 1575 | |
| 1576 | /* For each earlyclobber operand, zap the value data. */ |
| 1577 | for (i = 0; i < n_ops; i++) |
| 1578 | if (recog_op_alt[i][alt].earlyclobber) |
| 1579 | kill_value (recog_data.operand[i], vd); |
| 1580 | |
| 1581 | /* Within asms, a clobber cannot overlap inputs or outputs. |
| 1582 | I wouldn't think this were true for regular insns, but |
| 1583 | scan_rtx treats them like that... */ |
| 1584 | note_stores (PATTERN (insn), kill_clobbered_value, vd); |
| 1585 | |
| 1586 | /* Kill all auto-incremented values. */ |
| 1587 | /* ??? REG_INC is useless, since stack pushes aren't done that way. */ |
| 1588 | for_each_rtx (&PATTERN (insn), kill_autoinc_value, vd); |
| 1589 | |
| 1590 | /* Kill all early-clobbered operands. */ |
| 1591 | for (i = 0; i < n_ops; i++) |
| 1592 | if (recog_op_alt[i][alt].earlyclobber) |
| 1593 | kill_value (recog_data.operand[i], vd); |
| 1594 | |
| 1595 | /* Special-case plain move instructions, since we may well |
| 1596 | be able to do the move from a different register class. */ |
| 1597 | if (set && REG_P (SET_SRC (set))) |
| 1598 | { |
| 1599 | rtx src = SET_SRC (set); |
| 1600 | unsigned int regno = REGNO (src); |
| 1601 | enum machine_mode mode = GET_MODE (src); |
| 1602 | unsigned int i; |
| 1603 | rtx new; |
| 1604 | |
| 1605 | /* If we are accessing SRC in some mode other that what we |
| 1606 | set it in, make sure that the replacement is valid. */ |
| 1607 | if (mode != vd->e[regno].mode) |
| 1608 | { |
| 1609 | if (HARD_REGNO_NREGS (regno, mode) |
| 1610 | > HARD_REGNO_NREGS (regno, vd->e[regno].mode)) |
| 1611 | goto no_move_special_case; |
| 1612 | } |
| 1613 | |
| 1614 | /* If the destination is also a register, try to find a source |
| 1615 | register in the same class. */ |
| 1616 | if (REG_P (SET_DEST (set))) |
| 1617 | { |
| 1618 | new = find_oldest_value_reg (REGNO_REG_CLASS (regno), src, vd); |
| 1619 | if (new && validate_change (insn, &SET_SRC (set), new, 0)) |
| 1620 | { |
| 1621 | if (rtl_dump_file) |
| 1622 | fprintf (rtl_dump_file, |
| 1623 | "insn %u: replaced reg %u with %u\n", |
| 1624 | INSN_UID (insn), regno, REGNO (new)); |
| 1625 | changed = true; |
| 1626 | goto did_replacement; |
| 1627 | } |
| 1628 | } |
| 1629 | |
| 1630 | /* Otherwise, try all valid registers and see if its valid. */ |
| 1631 | for (i = vd->e[regno].oldest_regno; i != regno; |
| 1632 | i = vd->e[i].next_regno) |
| 1633 | { |
| 1634 | new = maybe_mode_change (vd->e[i].mode, vd->e[regno].mode, |
| 1635 | mode, i, regno); |
| 1636 | if (new != NULL_RTX) |
| 1637 | { |
| 1638 | if (validate_change (insn, &SET_SRC (set), new, 0)) |
| 1639 | { |
| 1640 | ORIGINAL_REGNO (new) = ORIGINAL_REGNO (src); |
| 1641 | REG_ATTRS (new) = REG_ATTRS (src); |
| 1642 | if (rtl_dump_file) |
| 1643 | fprintf (rtl_dump_file, |
| 1644 | "insn %u: replaced reg %u with %u\n", |
| 1645 | INSN_UID (insn), regno, REGNO (new)); |
| 1646 | changed = true; |
| 1647 | goto did_replacement; |
| 1648 | } |
| 1649 | } |
| 1650 | } |
| 1651 | } |
| 1652 | no_move_special_case: |
| 1653 | |
| 1654 | /* For each input operand, replace a hard register with the |
| 1655 | eldest live copy that's in an appropriate register class. */ |
| 1656 | for (i = 0; i < n_ops; i++) |
| 1657 | { |
| 1658 | bool replaced = false; |
| 1659 | |
| 1660 | /* Don't scan match_operand here, since we've no reg class |
| 1661 | information to pass down. Any operands that we could |
| 1662 | substitute in will be represented elsewhere. */ |
| 1663 | if (recog_data.constraints[i][0] == '\0') |
| 1664 | continue; |
| 1665 | |
| 1666 | /* Don't replace in asms intentionally referencing hard regs. */ |
| 1667 | if (is_asm && GET_CODE (recog_data.operand[i]) == REG |
| 1668 | && (REGNO (recog_data.operand[i]) |
| 1669 | == ORIGINAL_REGNO (recog_data.operand[i]))) |
| 1670 | continue; |
| 1671 | |
| 1672 | if (recog_data.operand_type[i] == OP_IN) |
| 1673 | { |
| 1674 | if (recog_op_alt[i][alt].is_address) |
| 1675 | replaced |
| 1676 | = replace_oldest_value_addr (recog_data.operand_loc[i], |
| 1677 | recog_op_alt[i][alt].class, |
| 1678 | VOIDmode, insn, vd); |
| 1679 | else if (REG_P (recog_data.operand[i])) |
| 1680 | replaced |
| 1681 | = replace_oldest_value_reg (recog_data.operand_loc[i], |
| 1682 | recog_op_alt[i][alt].class, |
| 1683 | insn, vd); |
| 1684 | else if (GET_CODE (recog_data.operand[i]) == MEM) |
| 1685 | replaced = replace_oldest_value_mem (recog_data.operand[i], |
| 1686 | insn, vd); |
| 1687 | } |
| 1688 | else if (GET_CODE (recog_data.operand[i]) == MEM) |
| 1689 | replaced = replace_oldest_value_mem (recog_data.operand[i], |
| 1690 | insn, vd); |
| 1691 | |
| 1692 | /* If we performed any replacement, update match_dups. */ |
| 1693 | if (replaced) |
| 1694 | { |
| 1695 | int j; |
| 1696 | rtx new; |
| 1697 | |
| 1698 | changed = true; |
| 1699 | |
| 1700 | new = *recog_data.operand_loc[i]; |
| 1701 | recog_data.operand[i] = new; |
| 1702 | for (j = 0; j < recog_data.n_dups; j++) |
| 1703 | if (recog_data.dup_num[j] == i) |
| 1704 | *recog_data.dup_loc[j] = new; |
| 1705 | } |
| 1706 | } |
| 1707 | |
| 1708 | did_replacement: |
| 1709 | /* Clobber call-clobbered registers. */ |
| 1710 | if (GET_CODE (insn) == CALL_INSN) |
| 1711 | for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) |
| 1712 | if (TEST_HARD_REG_BIT (regs_invalidated_by_call, i)) |
| 1713 | kill_value_regno (i, vd); |
| 1714 | |
| 1715 | /* Notice stores. */ |
| 1716 | note_stores (PATTERN (insn), kill_set_value, vd); |
| 1717 | |
| 1718 | /* Notice copies. */ |
| 1719 | if (set && REG_P (SET_DEST (set)) && REG_P (SET_SRC (set))) |
| 1720 | copy_value (SET_DEST (set), SET_SRC (set), vd); |
| 1721 | |
| 1722 | if (insn == BB_END (bb)) |
| 1723 | break; |
| 1724 | } |
| 1725 | |
| 1726 | return changed; |
| 1727 | } |
| 1728 | |
| 1729 | /* Main entry point for the forward copy propagation optimization. */ |
| 1730 | |
| 1731 | void |
| 1732 | copyprop_hardreg_forward (void) |
| 1733 | { |
| 1734 | struct value_data *all_vd; |
| 1735 | bool need_refresh; |
| 1736 | basic_block bb, bbp = 0; |
| 1737 | |
| 1738 | need_refresh = false; |
| 1739 | |
| 1740 | all_vd = xmalloc (sizeof (struct value_data) * last_basic_block); |
| 1741 | |
| 1742 | FOR_EACH_BB (bb) |
| 1743 | { |
| 1744 | /* If a block has a single predecessor, that we've already |
| 1745 | processed, begin with the value data that was live at |
| 1746 | the end of the predecessor block. */ |
| 1747 | /* ??? Ought to use more intelligent queuing of blocks. */ |
| 1748 | if (bb->pred) |
| 1749 | for (bbp = bb; bbp && bbp != bb->pred->src; bbp = bbp->prev_bb); |
| 1750 | if (bb->pred |
| 1751 | && ! bb->pred->pred_next |
| 1752 | && ! (bb->pred->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) |
| 1753 | && bb->pred->src != ENTRY_BLOCK_PTR |
| 1754 | && bbp) |
| 1755 | all_vd[bb->index] = all_vd[bb->pred->src->index]; |
| 1756 | else |
| 1757 | init_value_data (all_vd + bb->index); |
| 1758 | |
| 1759 | if (copyprop_hardreg_forward_1 (bb, all_vd + bb->index)) |
| 1760 | need_refresh = true; |
| 1761 | } |
| 1762 | |
| 1763 | if (need_refresh) |
| 1764 | { |
| 1765 | if (rtl_dump_file) |
| 1766 | fputs ("\n\n", rtl_dump_file); |
| 1767 | |
| 1768 | /* ??? Irritatingly, delete_noop_moves does not take a set of blocks |
| 1769 | to scan, so we have to do a life update with no initial set of |
| 1770 | blocks Just In Case. */ |
| 1771 | delete_noop_moves (get_insns ()); |
| 1772 | update_life_info (NULL, UPDATE_LIFE_GLOBAL_RM_NOTES, |
| 1773 | PROP_DEATH_NOTES |
| 1774 | | PROP_SCAN_DEAD_CODE |
| 1775 | | PROP_KILL_DEAD_CODE); |
| 1776 | } |
| 1777 | |
| 1778 | free (all_vd); |
| 1779 | } |
| 1780 | |
| 1781 | /* Dump the value chain data to stderr. */ |
| 1782 | |
| 1783 | void |
| 1784 | debug_value_data (struct value_data *vd) |
| 1785 | { |
| 1786 | HARD_REG_SET set; |
| 1787 | unsigned int i, j; |
| 1788 | |
| 1789 | CLEAR_HARD_REG_SET (set); |
| 1790 | |
| 1791 | for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i) |
| 1792 | if (vd->e[i].oldest_regno == i) |
| 1793 | { |
| 1794 | if (vd->e[i].mode == VOIDmode) |
| 1795 | { |
| 1796 | if (vd->e[i].next_regno != INVALID_REGNUM) |
| 1797 | fprintf (stderr, "[%u] Bad next_regno for empty chain (%u)\n", |
| 1798 | i, vd->e[i].next_regno); |
| 1799 | continue; |
| 1800 | } |
| 1801 | |
| 1802 | SET_HARD_REG_BIT (set, i); |
| 1803 | fprintf (stderr, "[%u %s] ", i, GET_MODE_NAME (vd->e[i].mode)); |
| 1804 | |
| 1805 | for (j = vd->e[i].next_regno; |
| 1806 | j != INVALID_REGNUM; |
| 1807 | j = vd->e[j].next_regno) |
| 1808 | { |
| 1809 | if (TEST_HARD_REG_BIT (set, j)) |
| 1810 | { |
| 1811 | fprintf (stderr, "[%u] Loop in regno chain\n", j); |
| 1812 | return; |
| 1813 | } |
| 1814 | |
| 1815 | if (vd->e[j].oldest_regno != i) |
| 1816 | { |
| 1817 | fprintf (stderr, "[%u] Bad oldest_regno (%u)\n", |
| 1818 | j, vd->e[j].oldest_regno); |
| 1819 | return; |
| 1820 | } |
| 1821 | SET_HARD_REG_BIT (set, j); |
| 1822 | fprintf (stderr, "[%u %s] ", j, GET_MODE_NAME (vd->e[j].mode)); |
| 1823 | } |
| 1824 | fputc ('\n', stderr); |
| 1825 | } |
| 1826 | |
| 1827 | for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i) |
| 1828 | if (! TEST_HARD_REG_BIT (set, i) |
| 1829 | && (vd->e[i].mode != VOIDmode |
| 1830 | || vd->e[i].oldest_regno != i |
| 1831 | || vd->e[i].next_regno != INVALID_REGNUM)) |
| 1832 | fprintf (stderr, "[%u] Non-empty reg in chain (%s %u %i)\n", |
| 1833 | i, GET_MODE_NAME (vd->e[i].mode), vd->e[i].oldest_regno, |
| 1834 | vd->e[i].next_regno); |
| 1835 | } |
| 1836 | |
| 1837 | #ifdef ENABLE_CHECKING |
| 1838 | static void |
| 1839 | validate_value_data (struct value_data *vd) |
| 1840 | { |
| 1841 | HARD_REG_SET set; |
| 1842 | unsigned int i, j; |
| 1843 | |
| 1844 | CLEAR_HARD_REG_SET (set); |
| 1845 | |
| 1846 | for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i) |
| 1847 | if (vd->e[i].oldest_regno == i) |
| 1848 | { |
| 1849 | if (vd->e[i].mode == VOIDmode) |
| 1850 | { |
| 1851 | if (vd->e[i].next_regno != INVALID_REGNUM) |
| 1852 | internal_error ("validate_value_data: [%u] Bad next_regno for empty chain (%u)", |
| 1853 | i, vd->e[i].next_regno); |
| 1854 | continue; |
| 1855 | } |
| 1856 | |
| 1857 | SET_HARD_REG_BIT (set, i); |
| 1858 | |
| 1859 | for (j = vd->e[i].next_regno; |
| 1860 | j != INVALID_REGNUM; |
| 1861 | j = vd->e[j].next_regno) |
| 1862 | { |
| 1863 | if (TEST_HARD_REG_BIT (set, j)) |
| 1864 | internal_error ("validate_value_data: Loop in regno chain (%u)", |
| 1865 | j); |
| 1866 | if (vd->e[j].oldest_regno != i) |
| 1867 | internal_error ("validate_value_data: [%u] Bad oldest_regno (%u)", |
| 1868 | j, vd->e[j].oldest_regno); |
| 1869 | |
| 1870 | SET_HARD_REG_BIT (set, j); |
| 1871 | } |
| 1872 | } |
| 1873 | |
| 1874 | for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i) |
| 1875 | if (! TEST_HARD_REG_BIT (set, i) |
| 1876 | && (vd->e[i].mode != VOIDmode |
| 1877 | || vd->e[i].oldest_regno != i |
| 1878 | || vd->e[i].next_regno != INVALID_REGNUM)) |
| 1879 | internal_error ("validate_value_data: [%u] Non-empty reg in chain (%s %u %i)", |
| 1880 | i, GET_MODE_NAME (vd->e[i].mode), vd->e[i].oldest_regno, |
| 1881 | vd->e[i].next_regno); |
| 1882 | } |
| 1883 | #endif |