1 /* IRA hard register and memory cost calculation for allocnos or pseudos. 2 Copyright (C) 2006-2020 Free Software Foundation, Inc. 3 Contributed by Vladimir Makarov <vmakarov@redhat.com>. 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify it under 8 the terms of the GNU General Public License as published by the Free 9 Software Foundation; either version 3, or (at your option) any later 10 version. 11 12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13 WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15 for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 #include "config.h" 22 #include "system.h" 23 #include "coretypes.h" 24 #include "backend.h" 25 #include "target.h" 26 #include "rtl.h" 27 #include "tree.h" 28 #include "predict.h" 29 #include "memmodel.h" 30 #include "tm_p.h" 31 #include "insn-config.h" 32 #include "regs.h" 33 #include "ira.h" 34 #include "ira-int.h" 35 #include "addresses.h" 36 #include "reload.h" 37 38 /* The flags is set up every time when we calculate pseudo register 39 classes through function ira_set_pseudo_classes. */ 40 static bool pseudo_classes_defined_p = false; 41 42 /* TRUE if we work with allocnos. Otherwise we work with pseudos. */ 43 static bool allocno_p; 44 45 /* Number of elements in array `costs'. */ 46 static int cost_elements_num; 47 48 /* The `costs' struct records the cost of using hard registers of each 49 class considered for the calculation and of using memory for each 50 allocno or pseudo. */ 51 struct costs 52 { 53 int mem_cost; 54 /* Costs for register classes start here. We process only some 55 allocno classes. */ 56 int cost[1]; 57 }; 58 59 #define max_struct_costs_size \ 60 (this_target_ira_int->x_max_struct_costs_size) 61 #define init_cost \ 62 (this_target_ira_int->x_init_cost) 63 #define temp_costs \ 64 (this_target_ira_int->x_temp_costs) 65 #define op_costs \ 66 (this_target_ira_int->x_op_costs) 67 #define this_op_costs \ 68 (this_target_ira_int->x_this_op_costs) 69 70 /* Costs of each class for each allocno or pseudo. */ 71 static struct costs *costs; 72 73 /* Accumulated costs of each class for each allocno. */ 74 static struct costs *total_allocno_costs; 75 76 /* It is the current size of struct costs. */ 77 static size_t struct_costs_size; 78 79 /* Return pointer to structure containing costs of allocno or pseudo 80 with given NUM in array ARR. */ 81 #define COSTS(arr, num) \ 82 ((struct costs *) ((char *) (arr) + (num) * struct_costs_size)) 83 84 /* Return index in COSTS when processing reg with REGNO. */ 85 #define COST_INDEX(regno) (allocno_p \ 86 ? ALLOCNO_NUM (ira_curr_regno_allocno_map[regno]) \ 87 : (int) regno) 88 89 /* Record register class preferences of each allocno or pseudo. Null 90 value means no preferences. It happens on the 1st iteration of the 91 cost calculation. */ 92 static enum reg_class *pref; 93 94 /* Allocated buffers for pref. */ 95 static enum reg_class *pref_buffer; 96 97 /* Record allocno class of each allocno with the same regno. */ 98 static enum reg_class *regno_aclass; 99 100 /* Record cost gains for not allocating a register with an invariant 101 equivalence. */ 102 static int *regno_equiv_gains; 103 104 /* Execution frequency of the current insn. */ 105 static int frequency; 106 107 108 109 /* Info about reg classes whose costs are calculated for a pseudo. */ 110 struct cost_classes 111 { 112 /* Number of the cost classes in the subsequent array. */ 113 int num; 114 /* Container of the cost classes. */ 115 enum reg_class classes[N_REG_CLASSES]; 116 /* Map reg class -> index of the reg class in the previous array. 117 -1 if it is not a cost class. */ 118 int index[N_REG_CLASSES]; 119 /* Map hard regno index of first class in array CLASSES containing 120 the hard regno, -1 otherwise. */ 121 int hard_regno_index[FIRST_PSEUDO_REGISTER]; 122 }; 123 124 /* Types of pointers to the structure above. */ 125 typedef struct cost_classes *cost_classes_t; 126 typedef const struct cost_classes *const_cost_classes_t; 127 128 /* Info about cost classes for each pseudo. */ 129 static cost_classes_t *regno_cost_classes; 130 131 /* Helper for cost_classes hashing. */ 132 133 struct cost_classes_hasher : pointer_hash <cost_classes> 134 { 135 static inline hashval_t hash (const cost_classes *); 136 static inline bool equal (const cost_classes *, const cost_classes *); 137 static inline void remove (cost_classes *); 138 }; 139 140 /* Returns hash value for cost classes info HV. */ 141 inline hashval_t 142 cost_classes_hasher::hash (const cost_classes *hv) 143 { 144 return iterative_hash (&hv->classes, sizeof (enum reg_class) * hv->num, 0); 145 } 146 147 /* Compares cost classes info HV1 and HV2. */ 148 inline bool 149 cost_classes_hasher::equal (const cost_classes *hv1, const cost_classes *hv2) 150 { 151 return (hv1->num == hv2->num 152 && memcmp (hv1->classes, hv2->classes, 153 sizeof (enum reg_class) * hv1->num) == 0); 154 } 155 156 /* Delete cost classes info V from the hash table. */ 157 inline void 158 cost_classes_hasher::remove (cost_classes *v) 159 { 160 ira_free (v); 161 } 162 163 /* Hash table of unique cost classes. */ 164 static hash_table<cost_classes_hasher> *cost_classes_htab; 165 166 /* Map allocno class -> cost classes for pseudo of given allocno 167 class. */ 168 static cost_classes_t cost_classes_aclass_cache[N_REG_CLASSES]; 169 170 /* Map mode -> cost classes for pseudo of give mode. */ 171 static cost_classes_t cost_classes_mode_cache[MAX_MACHINE_MODE]; 172 173 /* Cost classes that include all classes in ira_important_classes. */ 174 static cost_classes all_cost_classes; 175 176 /* Use the array of classes in CLASSES_PTR to fill out the rest of 177 the structure. */ 178 static void 179 complete_cost_classes (cost_classes_t classes_ptr) 180 { 181 for (int i = 0; i < N_REG_CLASSES; i++) 182 classes_ptr->index[i] = -1; 183 for (int i = 0; i < FIRST_PSEUDO_REGISTER; i++) 184 classes_ptr->hard_regno_index[i] = -1; 185 for (int i = 0; i < classes_ptr->num; i++) 186 { 187 enum reg_class cl = classes_ptr->classes[i]; 188 classes_ptr->index[cl] = i; 189 for (int j = ira_class_hard_regs_num[cl] - 1; j >= 0; j--) 190 { 191 unsigned int hard_regno = ira_class_hard_regs[cl][j]; 192 if (classes_ptr->hard_regno_index[hard_regno] < 0) 193 classes_ptr->hard_regno_index[hard_regno] = i; 194 } 195 } 196 } 197 198 /* Initialize info about the cost classes for each pseudo. */ 199 static void 200 initiate_regno_cost_classes (void) 201 { 202 int size = sizeof (cost_classes_t) * max_reg_num (); 203 204 regno_cost_classes = (cost_classes_t *) ira_allocate (size); 205 memset (regno_cost_classes, 0, size); 206 memset (cost_classes_aclass_cache, 0, 207 sizeof (cost_classes_t) * N_REG_CLASSES); 208 memset (cost_classes_mode_cache, 0, 209 sizeof (cost_classes_t) * MAX_MACHINE_MODE); 210 cost_classes_htab = new hash_table<cost_classes_hasher> (200); 211 all_cost_classes.num = ira_important_classes_num; 212 for (int i = 0; i < ira_important_classes_num; i++) 213 all_cost_classes.classes[i] = ira_important_classes[i]; 214 complete_cost_classes (&all_cost_classes); 215 } 216 217 /* Create new cost classes from cost classes FROM and set up members 218 index and hard_regno_index. Return the new classes. The function 219 implements some common code of two functions 220 setup_regno_cost_classes_by_aclass and 221 setup_regno_cost_classes_by_mode. */ 222 static cost_classes_t 223 setup_cost_classes (cost_classes_t from) 224 { 225 cost_classes_t classes_ptr; 226 227 classes_ptr = (cost_classes_t) ira_allocate (sizeof (struct cost_classes)); 228 classes_ptr->num = from->num; 229 for (int i = 0; i < from->num; i++) 230 classes_ptr->classes[i] = from->classes[i]; 231 complete_cost_classes (classes_ptr); 232 return classes_ptr; 233 } 234 235 /* Return a version of FULL that only considers registers in REGS that are 236 valid for mode MODE. Both FULL and the returned class are globally 237 allocated. */ 238 static cost_classes_t 239 restrict_cost_classes (cost_classes_t full, machine_mode mode, 240 const_hard_reg_set regs) 241 { 242 static struct cost_classes narrow; 243 int map[N_REG_CLASSES]; 244 narrow.num = 0; 245 for (int i = 0; i < full->num; i++) 246 { 247 /* Assume that we'll drop the class. */ 248 map[i] = -1; 249 250 /* Ignore classes that are too small for the mode. */ 251 enum reg_class cl = full->classes[i]; 252 if (!contains_reg_of_mode[cl][mode]) 253 continue; 254 255 /* Calculate the set of registers in CL that belong to REGS and 256 are valid for MODE. */ 257 HARD_REG_SET valid_for_cl = reg_class_contents[cl] & regs; 258 valid_for_cl &= ~(ira_prohibited_class_mode_regs[cl][mode] 259 | ira_no_alloc_regs); 260 if (hard_reg_set_empty_p (valid_for_cl)) 261 continue; 262 263 /* Don't use this class if the set of valid registers is a subset 264 of an existing class. For example, suppose we have two classes 265 GR_REGS and FR_REGS and a union class GR_AND_FR_REGS. Suppose 266 that the mode changes allowed by FR_REGS are not as general as 267 the mode changes allowed by GR_REGS. 268 269 In this situation, the mode changes for GR_AND_FR_REGS could 270 either be seen as the union or the intersection of the mode 271 changes allowed by the two subclasses. The justification for 272 the union-based definition would be that, if you want a mode 273 change that's only allowed by GR_REGS, you can pick a register 274 from the GR_REGS subclass. The justification for the 275 intersection-based definition would be that every register 276 from the class would allow the mode change. 277 278 However, if we have a register that needs to be in GR_REGS, 279 using GR_AND_FR_REGS with the intersection-based definition 280 would be too pessimistic, since it would bring in restrictions 281 that only apply to FR_REGS. Conversely, if we have a register 282 that needs to be in FR_REGS, using GR_AND_FR_REGS with the 283 union-based definition would lose the extra restrictions 284 placed on FR_REGS. GR_AND_FR_REGS is therefore only useful 285 for cases where GR_REGS and FP_REGS are both valid. */ 286 int pos; 287 for (pos = 0; pos < narrow.num; ++pos) 288 { 289 enum reg_class cl2 = narrow.classes[pos]; 290 if (hard_reg_set_subset_p (valid_for_cl, reg_class_contents[cl2])) 291 break; 292 } 293 map[i] = pos; 294 if (pos == narrow.num) 295 { 296 /* If several classes are equivalent, prefer to use the one 297 that was chosen as the allocno class. */ 298 enum reg_class cl2 = ira_allocno_class_translate[cl]; 299 if (ira_class_hard_regs_num[cl] == ira_class_hard_regs_num[cl2]) 300 cl = cl2; 301 narrow.classes[narrow.num++] = cl; 302 } 303 } 304 if (narrow.num == full->num) 305 return full; 306 307 cost_classes **slot = cost_classes_htab->find_slot (&narrow, INSERT); 308 if (*slot == NULL) 309 { 310 cost_classes_t classes = setup_cost_classes (&narrow); 311 /* Map equivalent classes to the representative that we chose above. */ 312 for (int i = 0; i < ira_important_classes_num; i++) 313 { 314 enum reg_class cl = ira_important_classes[i]; 315 int index = full->index[cl]; 316 if (index >= 0) 317 classes->index[cl] = map[index]; 318 } 319 *slot = classes; 320 } 321 return *slot; 322 } 323 324 /* Setup cost classes for pseudo REGNO whose allocno class is ACLASS. 325 This function is used when we know an initial approximation of 326 allocno class of the pseudo already, e.g. on the second iteration 327 of class cost calculation or after class cost calculation in 328 register-pressure sensitive insn scheduling or register-pressure 329 sensitive loop-invariant motion. */ 330 static void 331 setup_regno_cost_classes_by_aclass (int regno, enum reg_class aclass) 332 { 333 static struct cost_classes classes; 334 cost_classes_t classes_ptr; 335 enum reg_class cl; 336 int i; 337 cost_classes **slot; 338 HARD_REG_SET temp, temp2; 339 bool exclude_p; 340 341 if ((classes_ptr = cost_classes_aclass_cache[aclass]) == NULL) 342 { 343 temp = reg_class_contents[aclass] & ~ira_no_alloc_regs; 344 /* We exclude classes from consideration which are subsets of 345 ACLASS only if ACLASS is an uniform class. */ 346 exclude_p = ira_uniform_class_p[aclass]; 347 classes.num = 0; 348 for (i = 0; i < ira_important_classes_num; i++) 349 { 350 cl = ira_important_classes[i]; 351 if (exclude_p) 352 { 353 /* Exclude non-uniform classes which are subsets of 354 ACLASS. */ 355 temp2 = reg_class_contents[cl] & ~ira_no_alloc_regs; 356 if (hard_reg_set_subset_p (temp2, temp) && cl != aclass) 357 continue; 358 } 359 classes.classes[classes.num++] = cl; 360 } 361 slot = cost_classes_htab->find_slot (&classes, INSERT); 362 if (*slot == NULL) 363 { 364 classes_ptr = setup_cost_classes (&classes); 365 *slot = classes_ptr; 366 } 367 classes_ptr = cost_classes_aclass_cache[aclass] = (cost_classes_t) *slot; 368 } 369 if (regno_reg_rtx[regno] != NULL_RTX) 370 { 371 /* Restrict the classes to those that are valid for REGNO's mode 372 (which might for example exclude singleton classes if the mode 373 requires two registers). Also restrict the classes to those that 374 are valid for subregs of REGNO. */ 375 const HARD_REG_SET *valid_regs = valid_mode_changes_for_regno (regno); 376 if (!valid_regs) 377 valid_regs = ®_class_contents[ALL_REGS]; 378 classes_ptr = restrict_cost_classes (classes_ptr, 379 PSEUDO_REGNO_MODE (regno), 380 *valid_regs); 381 } 382 regno_cost_classes[regno] = classes_ptr; 383 } 384 385 /* Setup cost classes for pseudo REGNO with MODE. Usage of MODE can 386 decrease number of cost classes for the pseudo, if hard registers 387 of some important classes cannot hold a value of MODE. So the 388 pseudo cannot get hard register of some important classes and cost 389 calculation for such important classes is only wasting CPU 390 time. */ 391 static void 392 setup_regno_cost_classes_by_mode (int regno, machine_mode mode) 393 { 394 if (const HARD_REG_SET *valid_regs = valid_mode_changes_for_regno (regno)) 395 regno_cost_classes[regno] = restrict_cost_classes (&all_cost_classes, 396 mode, *valid_regs); 397 else 398 { 399 if (cost_classes_mode_cache[mode] == NULL) 400 cost_classes_mode_cache[mode] 401 = restrict_cost_classes (&all_cost_classes, mode, 402 reg_class_contents[ALL_REGS]); 403 regno_cost_classes[regno] = cost_classes_mode_cache[mode]; 404 } 405 } 406 407 /* Finalize info about the cost classes for each pseudo. */ 408 static void 409 finish_regno_cost_classes (void) 410 { 411 ira_free (regno_cost_classes); 412 delete cost_classes_htab; 413 cost_classes_htab = NULL; 414 } 415 416 417 418 /* Compute the cost of loading X into (if TO_P is TRUE) or from (if 419 TO_P is FALSE) a register of class RCLASS in mode MODE. X must not 420 be a pseudo register. */ 421 static int 422 copy_cost (rtx x, machine_mode mode, reg_class_t rclass, bool to_p, 423 secondary_reload_info *prev_sri) 424 { 425 secondary_reload_info sri; 426 reg_class_t secondary_class = NO_REGS; 427 428 /* If X is a SCRATCH, there is actually nothing to move since we are 429 assuming optimal allocation. */ 430 if (GET_CODE (x) == SCRATCH) 431 return 0; 432 433 /* Get the class we will actually use for a reload. */ 434 rclass = targetm.preferred_reload_class (x, rclass); 435 436 /* If we need a secondary reload for an intermediate, the cost is 437 that to load the input into the intermediate register, then to 438 copy it. */ 439 sri.prev_sri = prev_sri; 440 sri.extra_cost = 0; 441 /* PR 68770: Secondary reload might examine the t_icode field. */ 442 sri.t_icode = CODE_FOR_nothing; 443 444 secondary_class = targetm.secondary_reload (to_p, x, rclass, mode, &sri); 445 446 if (secondary_class != NO_REGS) 447 { 448 ira_init_register_move_cost_if_necessary (mode); 449 return (ira_register_move_cost[mode][(int) secondary_class][(int) rclass] 450 + sri.extra_cost 451 + copy_cost (x, mode, secondary_class, to_p, &sri)); 452 } 453 454 /* For memory, use the memory move cost, for (hard) registers, use 455 the cost to move between the register classes, and use 2 for 456 everything else (constants). */ 457 if (MEM_P (x) || rclass == NO_REGS) 458 return sri.extra_cost 459 + ira_memory_move_cost[mode][(int) rclass][to_p != 0]; 460 else if (REG_P (x)) 461 { 462 reg_class_t x_class = REGNO_REG_CLASS (REGNO (x)); 463 464 ira_init_register_move_cost_if_necessary (mode); 465 return (sri.extra_cost 466 + ira_register_move_cost[mode][(int) x_class][(int) rclass]); 467 } 468 else 469 /* If this is a constant, we may eventually want to call rtx_cost 470 here. */ 471 return sri.extra_cost + COSTS_N_INSNS (1); 472 } 473 474 475 476 /* Record the cost of using memory or hard registers of various 477 classes for the operands in INSN. 478 479 N_ALTS is the number of alternatives. 480 N_OPS is the number of operands. 481 OPS is an array of the operands. 482 MODES are the modes of the operands, in case any are VOIDmode. 483 CONSTRAINTS are the constraints to use for the operands. This array 484 is modified by this procedure. 485 486 This procedure works alternative by alternative. For each 487 alternative we assume that we will be able to allocate all allocnos 488 to their ideal register class and calculate the cost of using that 489 alternative. Then we compute, for each operand that is a 490 pseudo-register, the cost of having the allocno allocated to each 491 register class and using it in that alternative. To this cost is 492 added the cost of the alternative. 493 494 The cost of each class for this insn is its lowest cost among all 495 the alternatives. */ 496 static void 497 record_reg_classes (int n_alts, int n_ops, rtx *ops, 498 machine_mode *modes, const char **constraints, 499 rtx_insn *insn, enum reg_class *pref) 500 { 501 int alt; 502 int i, j, k; 503 int insn_allows_mem[MAX_RECOG_OPERANDS]; 504 move_table *move_in_cost, *move_out_cost; 505 short (*mem_cost)[2]; 506 507 for (i = 0; i < n_ops; i++) 508 insn_allows_mem[i] = 0; 509 510 /* Process each alternative, each time minimizing an operand's cost 511 with the cost for each operand in that alternative. */ 512 alternative_mask preferred = get_preferred_alternatives (insn); 513 for (alt = 0; alt < n_alts; alt++) 514 { 515 enum reg_class classes[MAX_RECOG_OPERANDS]; 516 int allows_mem[MAX_RECOG_OPERANDS]; 517 enum reg_class rclass; 518 int alt_fail = 0; 519 int alt_cost = 0, op_cost_add; 520 521 if (!TEST_BIT (preferred, alt)) 522 { 523 for (i = 0; i < recog_data.n_operands; i++) 524 constraints[i] = skip_alternative (constraints[i]); 525 526 continue; 527 } 528 529 for (i = 0; i < n_ops; i++) 530 { 531 unsigned char c; 532 const char *p = constraints[i]; 533 rtx op = ops[i]; 534 machine_mode mode = modes[i]; 535 int allows_addr = 0; 536 int win = 0; 537 538 /* Initially show we know nothing about the register class. */ 539 classes[i] = NO_REGS; 540 allows_mem[i] = 0; 541 542 /* If this operand has no constraints at all, we can 543 conclude nothing about it since anything is valid. */ 544 if (*p == 0) 545 { 546 if (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER) 547 memset (this_op_costs[i], 0, struct_costs_size); 548 continue; 549 } 550 551 /* If this alternative is only relevant when this operand 552 matches a previous operand, we do different things 553 depending on whether this operand is a allocno-reg or not. 554 We must process any modifiers for the operand before we 555 can make this test. */ 556 while (*p == '%' || *p == '=' || *p == '+' || *p == '&') 557 p++; 558 559 if (p[0] >= '0' && p[0] <= '0' + i) 560 { 561 /* Copy class and whether memory is allowed from the 562 matching alternative. Then perform any needed cost 563 computations and/or adjustments. */ 564 j = p[0] - '0'; 565 classes[i] = classes[j]; 566 allows_mem[i] = allows_mem[j]; 567 if (allows_mem[i]) 568 insn_allows_mem[i] = 1; 569 570 if (! REG_P (op) || REGNO (op) < FIRST_PSEUDO_REGISTER) 571 { 572 /* If this matches the other operand, we have no 573 added cost and we win. */ 574 if (rtx_equal_p (ops[j], op)) 575 win = 1; 576 /* If we can put the other operand into a register, 577 add to the cost of this alternative the cost to 578 copy this operand to the register used for the 579 other operand. */ 580 else if (classes[j] != NO_REGS) 581 { 582 alt_cost += copy_cost (op, mode, classes[j], 1, NULL); 583 win = 1; 584 } 585 } 586 else if (! REG_P (ops[j]) 587 || REGNO (ops[j]) < FIRST_PSEUDO_REGISTER) 588 { 589 /* This op is an allocno but the one it matches is 590 not. */ 591 592 /* If we can't put the other operand into a 593 register, this alternative can't be used. */ 594 595 if (classes[j] == NO_REGS) 596 alt_fail = 1; 597 /* Otherwise, add to the cost of this alternative 598 the cost to copy the other operand to the hard 599 register used for this operand. */ 600 else 601 alt_cost += copy_cost (ops[j], mode, classes[j], 1, NULL); 602 } 603 else 604 { 605 /* The costs of this operand are not the same as the 606 other operand since move costs are not symmetric. 607 Moreover, if we cannot tie them, this alternative 608 needs to do a copy, which is one insn. */ 609 struct costs *pp = this_op_costs[i]; 610 int *pp_costs = pp->cost; 611 cost_classes_t cost_classes_ptr 612 = regno_cost_classes[REGNO (op)]; 613 enum reg_class *cost_classes = cost_classes_ptr->classes; 614 bool in_p = recog_data.operand_type[i] != OP_OUT; 615 bool out_p = recog_data.operand_type[i] != OP_IN; 616 enum reg_class op_class = classes[i]; 617 618 ira_init_register_move_cost_if_necessary (mode); 619 if (! in_p) 620 { 621 ira_assert (out_p); 622 if (op_class == NO_REGS) 623 { 624 mem_cost = ira_memory_move_cost[mode]; 625 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 626 { 627 rclass = cost_classes[k]; 628 pp_costs[k] = mem_cost[rclass][0] * frequency; 629 } 630 } 631 else 632 { 633 move_out_cost = ira_may_move_out_cost[mode]; 634 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 635 { 636 rclass = cost_classes[k]; 637 pp_costs[k] 638 = move_out_cost[op_class][rclass] * frequency; 639 } 640 } 641 } 642 else if (! out_p) 643 { 644 ira_assert (in_p); 645 if (op_class == NO_REGS) 646 { 647 mem_cost = ira_memory_move_cost[mode]; 648 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 649 { 650 rclass = cost_classes[k]; 651 pp_costs[k] = mem_cost[rclass][1] * frequency; 652 } 653 } 654 else 655 { 656 move_in_cost = ira_may_move_in_cost[mode]; 657 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 658 { 659 rclass = cost_classes[k]; 660 pp_costs[k] 661 = move_in_cost[rclass][op_class] * frequency; 662 } 663 } 664 } 665 else 666 { 667 if (op_class == NO_REGS) 668 { 669 mem_cost = ira_memory_move_cost[mode]; 670 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 671 { 672 rclass = cost_classes[k]; 673 pp_costs[k] = ((mem_cost[rclass][0] 674 + mem_cost[rclass][1]) 675 * frequency); 676 } 677 } 678 else 679 { 680 move_in_cost = ira_may_move_in_cost[mode]; 681 move_out_cost = ira_may_move_out_cost[mode]; 682 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 683 { 684 rclass = cost_classes[k]; 685 pp_costs[k] = ((move_in_cost[rclass][op_class] 686 + move_out_cost[op_class][rclass]) 687 * frequency); 688 } 689 } 690 } 691 692 /* If the alternative actually allows memory, make 693 things a bit cheaper since we won't need an extra 694 insn to load it. */ 695 pp->mem_cost 696 = ((out_p ? ira_memory_move_cost[mode][op_class][0] : 0) 697 + (in_p ? ira_memory_move_cost[mode][op_class][1] : 0) 698 - allows_mem[i]) * frequency; 699 700 /* If we have assigned a class to this allocno in 701 our first pass, add a cost to this alternative 702 corresponding to what we would add if this 703 allocno were not in the appropriate class. */ 704 if (pref) 705 { 706 enum reg_class pref_class = pref[COST_INDEX (REGNO (op))]; 707 708 if (pref_class == NO_REGS) 709 alt_cost 710 += ((out_p 711 ? ira_memory_move_cost[mode][op_class][0] : 0) 712 + (in_p 713 ? ira_memory_move_cost[mode][op_class][1] 714 : 0)); 715 else if (ira_reg_class_intersect 716 [pref_class][op_class] == NO_REGS) 717 alt_cost 718 += ira_register_move_cost[mode][pref_class][op_class]; 719 } 720 if (REGNO (ops[i]) != REGNO (ops[j]) 721 && ! find_reg_note (insn, REG_DEAD, op)) 722 alt_cost += 2; 723 724 p++; 725 } 726 } 727 728 /* Scan all the constraint letters. See if the operand 729 matches any of the constraints. Collect the valid 730 register classes and see if this operand accepts 731 memory. */ 732 while ((c = *p)) 733 { 734 switch (c) 735 { 736 case '*': 737 /* Ignore the next letter for this pass. */ 738 c = *++p; 739 break; 740 741 case '^': 742 alt_cost += 2; 743 break; 744 745 case '?': 746 alt_cost += 2; 747 break; 748 749 case 'g': 750 if (MEM_P (op) 751 || (CONSTANT_P (op) 752 && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (op)))) 753 win = 1; 754 insn_allows_mem[i] = allows_mem[i] = 1; 755 classes[i] = ira_reg_class_subunion[classes[i]][GENERAL_REGS]; 756 break; 757 758 default: 759 enum constraint_num cn = lookup_constraint (p); 760 enum reg_class cl; 761 switch (get_constraint_type (cn)) 762 { 763 case CT_REGISTER: 764 cl = reg_class_for_constraint (cn); 765 if (cl != NO_REGS) 766 classes[i] = ira_reg_class_subunion[classes[i]][cl]; 767 break; 768 769 case CT_CONST_INT: 770 if (CONST_INT_P (op) 771 && insn_const_int_ok_for_constraint (INTVAL (op), cn)) 772 win = 1; 773 break; 774 775 case CT_MEMORY: 776 /* Every MEM can be reloaded to fit. */ 777 insn_allows_mem[i] = allows_mem[i] = 1; 778 if (MEM_P (op)) 779 win = 1; 780 break; 781 782 case CT_SPECIAL_MEMORY: 783 insn_allows_mem[i] = allows_mem[i] = 1; 784 if (MEM_P (op) && constraint_satisfied_p (op, cn)) 785 win = 1; 786 break; 787 788 case CT_ADDRESS: 789 /* Every address can be reloaded to fit. */ 790 allows_addr = 1; 791 if (address_operand (op, GET_MODE (op)) 792 || constraint_satisfied_p (op, cn)) 793 win = 1; 794 /* We know this operand is an address, so we 795 want it to be allocated to a hard register 796 that can be the base of an address, 797 i.e. BASE_REG_CLASS. */ 798 classes[i] 799 = ira_reg_class_subunion[classes[i]] 800 [base_reg_class (VOIDmode, ADDR_SPACE_GENERIC, 801 ADDRESS, SCRATCH)]; 802 break; 803 804 case CT_FIXED_FORM: 805 if (constraint_satisfied_p (op, cn)) 806 win = 1; 807 break; 808 } 809 break; 810 } 811 p += CONSTRAINT_LEN (c, p); 812 if (c == ',') 813 break; 814 } 815 816 constraints[i] = p; 817 818 if (alt_fail) 819 break; 820 821 /* How we account for this operand now depends on whether it 822 is a pseudo register or not. If it is, we first check if 823 any register classes are valid. If not, we ignore this 824 alternative, since we want to assume that all allocnos get 825 allocated for register preferencing. If some register 826 class is valid, compute the costs of moving the allocno 827 into that class. */ 828 if (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER) 829 { 830 if (classes[i] == NO_REGS && ! allows_mem[i]) 831 { 832 /* We must always fail if the operand is a REG, but 833 we did not find a suitable class and memory is 834 not allowed. 835 836 Otherwise we may perform an uninitialized read 837 from this_op_costs after the `continue' statement 838 below. */ 839 alt_fail = 1; 840 } 841 else 842 { 843 unsigned int regno = REGNO (op); 844 struct costs *pp = this_op_costs[i]; 845 int *pp_costs = pp->cost; 846 cost_classes_t cost_classes_ptr = regno_cost_classes[regno]; 847 enum reg_class *cost_classes = cost_classes_ptr->classes; 848 bool in_p = recog_data.operand_type[i] != OP_OUT; 849 bool out_p = recog_data.operand_type[i] != OP_IN; 850 enum reg_class op_class = classes[i]; 851 852 ira_init_register_move_cost_if_necessary (mode); 853 if (! in_p) 854 { 855 ira_assert (out_p); 856 if (op_class == NO_REGS) 857 { 858 mem_cost = ira_memory_move_cost[mode]; 859 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 860 { 861 rclass = cost_classes[k]; 862 pp_costs[k] = mem_cost[rclass][0] * frequency; 863 } 864 } 865 else 866 { 867 move_out_cost = ira_may_move_out_cost[mode]; 868 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 869 { 870 rclass = cost_classes[k]; 871 pp_costs[k] 872 = move_out_cost[op_class][rclass] * frequency; 873 } 874 } 875 } 876 else if (! out_p) 877 { 878 ira_assert (in_p); 879 if (op_class == NO_REGS) 880 { 881 mem_cost = ira_memory_move_cost[mode]; 882 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 883 { 884 rclass = cost_classes[k]; 885 pp_costs[k] = mem_cost[rclass][1] * frequency; 886 } 887 } 888 else 889 { 890 move_in_cost = ira_may_move_in_cost[mode]; 891 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 892 { 893 rclass = cost_classes[k]; 894 pp_costs[k] 895 = move_in_cost[rclass][op_class] * frequency; 896 } 897 } 898 } 899 else 900 { 901 if (op_class == NO_REGS) 902 { 903 mem_cost = ira_memory_move_cost[mode]; 904 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 905 { 906 rclass = cost_classes[k]; 907 pp_costs[k] = ((mem_cost[rclass][0] 908 + mem_cost[rclass][1]) 909 * frequency); 910 } 911 } 912 else 913 { 914 move_in_cost = ira_may_move_in_cost[mode]; 915 move_out_cost = ira_may_move_out_cost[mode]; 916 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 917 { 918 rclass = cost_classes[k]; 919 pp_costs[k] = ((move_in_cost[rclass][op_class] 920 + move_out_cost[op_class][rclass]) 921 * frequency); 922 } 923 } 924 } 925 926 if (op_class == NO_REGS) 927 /* Although we don't need insn to reload from 928 memory, still accessing memory is usually more 929 expensive than a register. */ 930 pp->mem_cost = frequency; 931 else 932 /* If the alternative actually allows memory, make 933 things a bit cheaper since we won't need an 934 extra insn to load it. */ 935 pp->mem_cost 936 = ((out_p ? ira_memory_move_cost[mode][op_class][0] : 0) 937 + (in_p ? ira_memory_move_cost[mode][op_class][1] : 0) 938 - allows_mem[i]) * frequency; 939 /* If we have assigned a class to this allocno in 940 our first pass, add a cost to this alternative 941 corresponding to what we would add if this 942 allocno were not in the appropriate class. */ 943 if (pref) 944 { 945 enum reg_class pref_class = pref[COST_INDEX (REGNO (op))]; 946 947 if (pref_class == NO_REGS) 948 { 949 if (op_class != NO_REGS) 950 alt_cost 951 += ((out_p 952 ? ira_memory_move_cost[mode][op_class][0] 953 : 0) 954 + (in_p 955 ? ira_memory_move_cost[mode][op_class][1] 956 : 0)); 957 } 958 else if (op_class == NO_REGS) 959 alt_cost 960 += ((out_p 961 ? ira_memory_move_cost[mode][pref_class][1] 962 : 0) 963 + (in_p 964 ? ira_memory_move_cost[mode][pref_class][0] 965 : 0)); 966 else if (ira_reg_class_intersect[pref_class][op_class] 967 == NO_REGS) 968 alt_cost += (ira_register_move_cost 969 [mode][pref_class][op_class]); 970 } 971 } 972 } 973 974 /* Otherwise, if this alternative wins, either because we 975 have already determined that or if we have a hard 976 register of the proper class, there is no cost for this 977 alternative. */ 978 else if (win || (REG_P (op) 979 && reg_fits_class_p (op, classes[i], 980 0, GET_MODE (op)))) 981 ; 982 983 /* If registers are valid, the cost of this alternative 984 includes copying the object to and/or from a 985 register. */ 986 else if (classes[i] != NO_REGS) 987 { 988 if (recog_data.operand_type[i] != OP_OUT) 989 alt_cost += copy_cost (op, mode, classes[i], 1, NULL); 990 991 if (recog_data.operand_type[i] != OP_IN) 992 alt_cost += copy_cost (op, mode, classes[i], 0, NULL); 993 } 994 /* The only other way this alternative can be used is if 995 this is a constant that could be placed into memory. */ 996 else if (CONSTANT_P (op) && (allows_addr || allows_mem[i])) 997 alt_cost += ira_memory_move_cost[mode][classes[i]][1]; 998 else 999 alt_fail = 1; 1000 1001 if (alt_fail) 1002 break; 1003 } 1004 1005 if (alt_fail) 1006 { 1007 /* The loop above might have exited early once the failure 1008 was seen. Skip over the constraints for the remaining 1009 operands. */ 1010 i += 1; 1011 for (; i < n_ops; ++i) 1012 constraints[i] = skip_alternative (constraints[i]); 1013 continue; 1014 } 1015 1016 op_cost_add = alt_cost * frequency; 1017 /* Finally, update the costs with the information we've 1018 calculated about this alternative. */ 1019 for (i = 0; i < n_ops; i++) 1020 if (REG_P (ops[i]) && REGNO (ops[i]) >= FIRST_PSEUDO_REGISTER) 1021 { 1022 struct costs *pp = op_costs[i], *qq = this_op_costs[i]; 1023 int *pp_costs = pp->cost, *qq_costs = qq->cost; 1024 int scale = 1 + (recog_data.operand_type[i] == OP_INOUT); 1025 cost_classes_t cost_classes_ptr 1026 = regno_cost_classes[REGNO (ops[i])]; 1027 1028 pp->mem_cost = MIN (pp->mem_cost, 1029 (qq->mem_cost + op_cost_add) * scale); 1030 1031 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 1032 pp_costs[k] 1033 = MIN (pp_costs[k], (qq_costs[k] + op_cost_add) * scale); 1034 } 1035 } 1036 1037 if (allocno_p) 1038 for (i = 0; i < n_ops; i++) 1039 { 1040 ira_allocno_t a; 1041 rtx op = ops[i]; 1042 1043 if (! REG_P (op) || REGNO (op) < FIRST_PSEUDO_REGISTER) 1044 continue; 1045 a = ira_curr_regno_allocno_map [REGNO (op)]; 1046 if (! ALLOCNO_BAD_SPILL_P (a) && insn_allows_mem[i] == 0) 1047 ALLOCNO_BAD_SPILL_P (a) = true; 1048 } 1049 1050 } 1051 1052 1053 1054 /* Wrapper around REGNO_OK_FOR_INDEX_P, to allow pseudo registers. */ 1055 static inline bool 1056 ok_for_index_p_nonstrict (rtx reg) 1057 { 1058 unsigned regno = REGNO (reg); 1059 1060 return regno >= FIRST_PSEUDO_REGISTER || REGNO_OK_FOR_INDEX_P (regno); 1061 } 1062 1063 /* A version of regno_ok_for_base_p for use here, when all 1064 pseudo-registers should count as OK. Arguments as for 1065 regno_ok_for_base_p. */ 1066 static inline bool 1067 ok_for_base_p_nonstrict (rtx reg, machine_mode mode, addr_space_t as, 1068 enum rtx_code outer_code, enum rtx_code index_code) 1069 { 1070 unsigned regno = REGNO (reg); 1071 1072 if (regno >= FIRST_PSEUDO_REGISTER) 1073 return true; 1074 return ok_for_base_p_1 (regno, mode, as, outer_code, index_code); 1075 } 1076 1077 /* Record the pseudo registers we must reload into hard registers in a 1078 subexpression of a memory address, X. 1079 1080 If CONTEXT is 0, we are looking at the base part of an address, 1081 otherwise we are looking at the index part. 1082 1083 MODE and AS are the mode and address space of the memory reference; 1084 OUTER_CODE and INDEX_CODE give the context that the rtx appears in. 1085 These four arguments are passed down to base_reg_class. 1086 1087 SCALE is twice the amount to multiply the cost by (it is twice so 1088 we can represent half-cost adjustments). */ 1089 static void 1090 record_address_regs (machine_mode mode, addr_space_t as, rtx x, 1091 int context, enum rtx_code outer_code, 1092 enum rtx_code index_code, int scale) 1093 { 1094 enum rtx_code code = GET_CODE (x); 1095 enum reg_class rclass; 1096 1097 if (context == 1) 1098 rclass = INDEX_REG_CLASS; 1099 else 1100 rclass = base_reg_class (mode, as, outer_code, index_code); 1101 1102 switch (code) 1103 { 1104 case CONST_INT: 1105 case CONST: 1106 case CC0: 1107 case PC: 1108 case SYMBOL_REF: 1109 case LABEL_REF: 1110 return; 1111 1112 case PLUS: 1113 /* When we have an address that is a sum, we must determine 1114 whether registers are "base" or "index" regs. If there is a 1115 sum of two registers, we must choose one to be the "base". 1116 Luckily, we can use the REG_POINTER to make a good choice 1117 most of the time. We only need to do this on machines that 1118 can have two registers in an address and where the base and 1119 index register classes are different. 1120 1121 ??? This code used to set REGNO_POINTER_FLAG in some cases, 1122 but that seems bogus since it should only be set when we are 1123 sure the register is being used as a pointer. */ 1124 { 1125 rtx arg0 = XEXP (x, 0); 1126 rtx arg1 = XEXP (x, 1); 1127 enum rtx_code code0 = GET_CODE (arg0); 1128 enum rtx_code code1 = GET_CODE (arg1); 1129 1130 /* Look inside subregs. */ 1131 if (code0 == SUBREG) 1132 arg0 = SUBREG_REG (arg0), code0 = GET_CODE (arg0); 1133 if (code1 == SUBREG) 1134 arg1 = SUBREG_REG (arg1), code1 = GET_CODE (arg1); 1135 1136 /* If index registers do not appear, or coincide with base registers, 1137 just record registers in any non-constant operands. We 1138 assume here, as well as in the tests below, that all 1139 addresses are in canonical form. */ 1140 if (MAX_REGS_PER_ADDRESS == 1 1141 || INDEX_REG_CLASS == base_reg_class (VOIDmode, as, PLUS, SCRATCH)) 1142 { 1143 record_address_regs (mode, as, arg0, context, PLUS, code1, scale); 1144 if (! CONSTANT_P (arg1)) 1145 record_address_regs (mode, as, arg1, context, PLUS, code0, scale); 1146 } 1147 1148 /* If the second operand is a constant integer, it doesn't 1149 change what class the first operand must be. */ 1150 else if (CONST_SCALAR_INT_P (arg1)) 1151 record_address_regs (mode, as, arg0, context, PLUS, code1, scale); 1152 /* If the second operand is a symbolic constant, the first 1153 operand must be an index register. */ 1154 else if (code1 == SYMBOL_REF || code1 == CONST || code1 == LABEL_REF) 1155 record_address_regs (mode, as, arg0, 1, PLUS, code1, scale); 1156 /* If both operands are registers but one is already a hard 1157 register of index or reg-base class, give the other the 1158 class that the hard register is not. */ 1159 else if (code0 == REG && code1 == REG 1160 && REGNO (arg0) < FIRST_PSEUDO_REGISTER 1161 && (ok_for_base_p_nonstrict (arg0, mode, as, PLUS, REG) 1162 || ok_for_index_p_nonstrict (arg0))) 1163 record_address_regs (mode, as, arg1, 1164 ok_for_base_p_nonstrict (arg0, mode, as, 1165 PLUS, REG) ? 1 : 0, 1166 PLUS, REG, scale); 1167 else if (code0 == REG && code1 == REG 1168 && REGNO (arg1) < FIRST_PSEUDO_REGISTER 1169 && (ok_for_base_p_nonstrict (arg1, mode, as, PLUS, REG) 1170 || ok_for_index_p_nonstrict (arg1))) 1171 record_address_regs (mode, as, arg0, 1172 ok_for_base_p_nonstrict (arg1, mode, as, 1173 PLUS, REG) ? 1 : 0, 1174 PLUS, REG, scale); 1175 /* If one operand is known to be a pointer, it must be the 1176 base with the other operand the index. Likewise if the 1177 other operand is a MULT. */ 1178 else if ((code0 == REG && REG_POINTER (arg0)) || code1 == MULT) 1179 { 1180 record_address_regs (mode, as, arg0, 0, PLUS, code1, scale); 1181 record_address_regs (mode, as, arg1, 1, PLUS, code0, scale); 1182 } 1183 else if ((code1 == REG && REG_POINTER (arg1)) || code0 == MULT) 1184 { 1185 record_address_regs (mode, as, arg0, 1, PLUS, code1, scale); 1186 record_address_regs (mode, as, arg1, 0, PLUS, code0, scale); 1187 } 1188 /* Otherwise, count equal chances that each might be a base or 1189 index register. This case should be rare. */ 1190 else 1191 { 1192 record_address_regs (mode, as, arg0, 0, PLUS, code1, scale / 2); 1193 record_address_regs (mode, as, arg0, 1, PLUS, code1, scale / 2); 1194 record_address_regs (mode, as, arg1, 0, PLUS, code0, scale / 2); 1195 record_address_regs (mode, as, arg1, 1, PLUS, code0, scale / 2); 1196 } 1197 } 1198 break; 1199 1200 /* Double the importance of an allocno that is incremented or 1201 decremented, since it would take two extra insns if it ends 1202 up in the wrong place. */ 1203 case POST_MODIFY: 1204 case PRE_MODIFY: 1205 record_address_regs (mode, as, XEXP (x, 0), 0, code, 1206 GET_CODE (XEXP (XEXP (x, 1), 1)), 2 * scale); 1207 if (REG_P (XEXP (XEXP (x, 1), 1))) 1208 record_address_regs (mode, as, XEXP (XEXP (x, 1), 1), 1, code, REG, 1209 2 * scale); 1210 break; 1211 1212 case POST_INC: 1213 case PRE_INC: 1214 case POST_DEC: 1215 case PRE_DEC: 1216 /* Double the importance of an allocno that is incremented or 1217 decremented, since it would take two extra insns if it ends 1218 up in the wrong place. */ 1219 record_address_regs (mode, as, XEXP (x, 0), 0, code, SCRATCH, 2 * scale); 1220 break; 1221 1222 case REG: 1223 { 1224 struct costs *pp; 1225 int *pp_costs; 1226 enum reg_class i; 1227 int k, regno, add_cost; 1228 cost_classes_t cost_classes_ptr; 1229 enum reg_class *cost_classes; 1230 move_table *move_in_cost; 1231 1232 if (REGNO (x) < FIRST_PSEUDO_REGISTER) 1233 break; 1234 1235 regno = REGNO (x); 1236 if (allocno_p) 1237 ALLOCNO_BAD_SPILL_P (ira_curr_regno_allocno_map[regno]) = true; 1238 pp = COSTS (costs, COST_INDEX (regno)); 1239 add_cost = (ira_memory_move_cost[Pmode][rclass][1] * scale) / 2; 1240 if (INT_MAX - add_cost < pp->mem_cost) 1241 pp->mem_cost = INT_MAX; 1242 else 1243 pp->mem_cost += add_cost; 1244 cost_classes_ptr = regno_cost_classes[regno]; 1245 cost_classes = cost_classes_ptr->classes; 1246 pp_costs = pp->cost; 1247 ira_init_register_move_cost_if_necessary (Pmode); 1248 move_in_cost = ira_may_move_in_cost[Pmode]; 1249 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 1250 { 1251 i = cost_classes[k]; 1252 add_cost = (move_in_cost[i][rclass] * scale) / 2; 1253 if (INT_MAX - add_cost < pp_costs[k]) 1254 pp_costs[k] = INT_MAX; 1255 else 1256 pp_costs[k] += add_cost; 1257 } 1258 } 1259 break; 1260 1261 default: 1262 { 1263 const char *fmt = GET_RTX_FORMAT (code); 1264 int i; 1265 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 1266 if (fmt[i] == 'e') 1267 record_address_regs (mode, as, XEXP (x, i), context, code, SCRATCH, 1268 scale); 1269 } 1270 } 1271 } 1272 1273 1274 1275 /* Calculate the costs of insn operands. */ 1276 static void 1277 record_operand_costs (rtx_insn *insn, enum reg_class *pref) 1278 { 1279 const char *constraints[MAX_RECOG_OPERANDS]; 1280 machine_mode modes[MAX_RECOG_OPERANDS]; 1281 rtx set; 1282 int i; 1283 1284 if ((set = single_set (insn)) != NULL_RTX 1285 /* In rare cases the single set insn might have less 2 operands 1286 as the source can be a fixed special reg. */ 1287 && recog_data.n_operands > 1 1288 && recog_data.operand[0] == SET_DEST (set) 1289 && recog_data.operand[1] == SET_SRC (set)) 1290 { 1291 int regno, other_regno; 1292 rtx dest = SET_DEST (set); 1293 rtx src = SET_SRC (set); 1294 1295 if (GET_CODE (dest) == SUBREG 1296 && known_eq (GET_MODE_SIZE (GET_MODE (dest)), 1297 GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest))))) 1298 dest = SUBREG_REG (dest); 1299 if (GET_CODE (src) == SUBREG 1300 && known_eq (GET_MODE_SIZE (GET_MODE (src)), 1301 GET_MODE_SIZE (GET_MODE (SUBREG_REG (src))))) 1302 src = SUBREG_REG (src); 1303 if (REG_P (src) && REG_P (dest) 1304 && (((regno = REGNO (src)) >= FIRST_PSEUDO_REGISTER 1305 && (other_regno = REGNO (dest)) < FIRST_PSEUDO_REGISTER) 1306 || ((regno = REGNO (dest)) >= FIRST_PSEUDO_REGISTER 1307 && (other_regno = REGNO (src)) < FIRST_PSEUDO_REGISTER))) 1308 { 1309 machine_mode mode = GET_MODE (SET_SRC (set)); 1310 cost_classes_t cost_classes_ptr = regno_cost_classes[regno]; 1311 enum reg_class *cost_classes = cost_classes_ptr->classes; 1312 reg_class_t rclass, hard_reg_class, pref_class, bigger_hard_reg_class; 1313 int cost, k; 1314 move_table *move_costs; 1315 bool dead_p = find_regno_note (insn, REG_DEAD, REGNO (src)); 1316 1317 ira_init_register_move_cost_if_necessary (mode); 1318 move_costs = ira_register_move_cost[mode]; 1319 hard_reg_class = REGNO_REG_CLASS (other_regno); 1320 bigger_hard_reg_class = ira_pressure_class_translate[hard_reg_class]; 1321 /* Target code may return any cost for mode which does not 1322 fit the hard reg class (e.g. DImode for AREG on 1323 i386). Check this and use a bigger class to get the 1324 right cost. */ 1325 if (bigger_hard_reg_class != NO_REGS 1326 && ! ira_hard_reg_in_set_p (other_regno, mode, 1327 reg_class_contents[hard_reg_class])) 1328 hard_reg_class = bigger_hard_reg_class; 1329 i = regno == (int) REGNO (src) ? 1 : 0; 1330 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 1331 { 1332 rclass = cost_classes[k]; 1333 cost = (i == 0 1334 ? move_costs[hard_reg_class][rclass] 1335 : move_costs[rclass][hard_reg_class]); 1336 1337 op_costs[i]->cost[k] = cost * frequency; 1338 /* If we have assigned a class to this allocno in our 1339 first pass, add a cost to this alternative 1340 corresponding to what we would add if this allocno 1341 were not in the appropriate class. */ 1342 if (pref) 1343 { 1344 if ((pref_class = pref[COST_INDEX (regno)]) == NO_REGS) 1345 op_costs[i]->cost[k] 1346 += ((i == 0 ? ira_memory_move_cost[mode][rclass][0] : 0) 1347 + (i == 1 ? ira_memory_move_cost[mode][rclass][1] : 0) 1348 * frequency); 1349 else if (ira_reg_class_intersect[pref_class][rclass] 1350 == NO_REGS) 1351 op_costs[i]->cost[k] 1352 += (move_costs[pref_class][rclass] 1353 * frequency); 1354 } 1355 /* If this insn is a single set copying operand 1 to 1356 operand 0 and one operand is an allocno with the 1357 other a hard reg or an allocno that prefers a hard 1358 register that is in its own register class then we 1359 may want to adjust the cost of that register class to 1360 -1. 1361 1362 Avoid the adjustment if the source does not die to 1363 avoid stressing of register allocator by preferencing 1364 two colliding registers into single class. */ 1365 if (dead_p 1366 && TEST_HARD_REG_BIT (reg_class_contents[rclass], other_regno) 1367 && (reg_class_size[(int) rclass] 1368 == (ira_reg_class_max_nregs 1369 [(int) rclass][(int) GET_MODE(src)]))) 1370 { 1371 if (reg_class_size[rclass] == 1) 1372 op_costs[i]->cost[k] = -frequency; 1373 else if (in_hard_reg_set_p (reg_class_contents[rclass], 1374 GET_MODE(src), other_regno)) 1375 op_costs[i]->cost[k] = -frequency; 1376 } 1377 } 1378 op_costs[i]->mem_cost 1379 = ira_memory_move_cost[mode][hard_reg_class][i] * frequency; 1380 if (pref && (pref_class = pref[COST_INDEX (regno)]) != NO_REGS) 1381 op_costs[i]->mem_cost 1382 += ira_memory_move_cost[mode][pref_class][i] * frequency; 1383 return; 1384 } 1385 } 1386 1387 for (i = 0; i < recog_data.n_operands; i++) 1388 { 1389 constraints[i] = recog_data.constraints[i]; 1390 modes[i] = recog_data.operand_mode[i]; 1391 } 1392 1393 /* If we get here, we are set up to record the costs of all the 1394 operands for this insn. Start by initializing the costs. Then 1395 handle any address registers. Finally record the desired classes 1396 for any allocnos, doing it twice if some pair of operands are 1397 commutative. */ 1398 for (i = 0; i < recog_data.n_operands; i++) 1399 { 1400 memcpy (op_costs[i], init_cost, struct_costs_size); 1401 1402 if (GET_CODE (recog_data.operand[i]) == SUBREG) 1403 recog_data.operand[i] = SUBREG_REG (recog_data.operand[i]); 1404 1405 if (MEM_P (recog_data.operand[i])) 1406 record_address_regs (GET_MODE (recog_data.operand[i]), 1407 MEM_ADDR_SPACE (recog_data.operand[i]), 1408 XEXP (recog_data.operand[i], 0), 1409 0, MEM, SCRATCH, frequency * 2); 1410 else if (constraints[i][0] == 'p' 1411 || (insn_extra_address_constraint 1412 (lookup_constraint (constraints[i])))) 1413 record_address_regs (VOIDmode, ADDR_SPACE_GENERIC, 1414 recog_data.operand[i], 0, ADDRESS, SCRATCH, 1415 frequency * 2); 1416 } 1417 1418 /* Check for commutative in a separate loop so everything will have 1419 been initialized. We must do this even if one operand is a 1420 constant--see addsi3 in m68k.md. */ 1421 for (i = 0; i < (int) recog_data.n_operands - 1; i++) 1422 if (constraints[i][0] == '%') 1423 { 1424 const char *xconstraints[MAX_RECOG_OPERANDS]; 1425 int j; 1426 1427 /* Handle commutative operands by swapping the 1428 constraints. We assume the modes are the same. */ 1429 for (j = 0; j < recog_data.n_operands; j++) 1430 xconstraints[j] = constraints[j]; 1431 1432 xconstraints[i] = constraints[i+1]; 1433 xconstraints[i+1] = constraints[i]; 1434 record_reg_classes (recog_data.n_alternatives, recog_data.n_operands, 1435 recog_data.operand, modes, 1436 xconstraints, insn, pref); 1437 } 1438 record_reg_classes (recog_data.n_alternatives, recog_data.n_operands, 1439 recog_data.operand, modes, 1440 constraints, insn, pref); 1441 } 1442 1443 1444 1445 /* Process one insn INSN. Scan it and record each time it would save 1446 code to put a certain allocnos in a certain class. Return the last 1447 insn processed, so that the scan can be continued from there. */ 1448 static rtx_insn * 1449 scan_one_insn (rtx_insn *insn) 1450 { 1451 enum rtx_code pat_code; 1452 rtx set, note; 1453 int i, k; 1454 bool counted_mem; 1455 1456 if (!NONDEBUG_INSN_P (insn)) 1457 return insn; 1458 1459 pat_code = GET_CODE (PATTERN (insn)); 1460 if (pat_code == ASM_INPUT) 1461 return insn; 1462 1463 /* If INSN is a USE/CLOBBER of a pseudo in a mode M then go ahead 1464 and initialize the register move costs of mode M. 1465 1466 The pseudo may be related to another pseudo via a copy (implicit or 1467 explicit) and if there are no mode M uses/sets of the original 1468 pseudo, then we may leave the register move costs uninitialized for 1469 mode M. */ 1470 if (pat_code == USE || pat_code == CLOBBER) 1471 { 1472 rtx x = XEXP (PATTERN (insn), 0); 1473 if (GET_CODE (x) == REG 1474 && REGNO (x) >= FIRST_PSEUDO_REGISTER 1475 && have_regs_of_mode[GET_MODE (x)]) 1476 ira_init_register_move_cost_if_necessary (GET_MODE (x)); 1477 return insn; 1478 } 1479 1480 counted_mem = false; 1481 set = single_set (insn); 1482 extract_insn (insn); 1483 1484 /* If this insn loads a parameter from its stack slot, then it 1485 represents a savings, rather than a cost, if the parameter is 1486 stored in memory. Record this fact. 1487 1488 Similarly if we're loading other constants from memory (constant 1489 pool, TOC references, small data areas, etc) and this is the only 1490 assignment to the destination pseudo. 1491 1492 Don't do this if SET_SRC (set) isn't a general operand, if it is 1493 a memory requiring special instructions to load it, decreasing 1494 mem_cost might result in it being loaded using the specialized 1495 instruction into a register, then stored into stack and loaded 1496 again from the stack. See PR52208. 1497 1498 Don't do this if SET_SRC (set) has side effect. See PR56124. */ 1499 if (set != 0 && REG_P (SET_DEST (set)) && MEM_P (SET_SRC (set)) 1500 && (note = find_reg_note (insn, REG_EQUIV, NULL_RTX)) != NULL_RTX 1501 && ((MEM_P (XEXP (note, 0)) 1502 && !side_effects_p (SET_SRC (set))) 1503 || (CONSTANT_P (XEXP (note, 0)) 1504 && targetm.legitimate_constant_p (GET_MODE (SET_DEST (set)), 1505 XEXP (note, 0)) 1506 && REG_N_SETS (REGNO (SET_DEST (set))) == 1)) 1507 && general_operand (SET_SRC (set), GET_MODE (SET_SRC (set))) 1508 /* LRA does not use equiv with a symbol for PIC code. */ 1509 && (! ira_use_lra_p || ! pic_offset_table_rtx 1510 || ! contains_symbol_ref_p (XEXP (note, 0)))) 1511 { 1512 enum reg_class cl = GENERAL_REGS; 1513 rtx reg = SET_DEST (set); 1514 int num = COST_INDEX (REGNO (reg)); 1515 1516 COSTS (costs, num)->mem_cost 1517 -= ira_memory_move_cost[GET_MODE (reg)][cl][1] * frequency; 1518 record_address_regs (GET_MODE (SET_SRC (set)), 1519 MEM_ADDR_SPACE (SET_SRC (set)), 1520 XEXP (SET_SRC (set), 0), 0, MEM, SCRATCH, 1521 frequency * 2); 1522 counted_mem = true; 1523 } 1524 1525 record_operand_costs (insn, pref); 1526 1527 /* Now add the cost for each operand to the total costs for its 1528 allocno. */ 1529 for (i = 0; i < recog_data.n_operands; i++) 1530 { 1531 rtx op = recog_data.operand[i]; 1532 1533 if (GET_CODE (op) == SUBREG) 1534 op = SUBREG_REG (op); 1535 if (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER) 1536 { 1537 int regno = REGNO (op); 1538 struct costs *p = COSTS (costs, COST_INDEX (regno)); 1539 struct costs *q = op_costs[i]; 1540 int *p_costs = p->cost, *q_costs = q->cost; 1541 cost_classes_t cost_classes_ptr = regno_cost_classes[regno]; 1542 int add_cost; 1543 1544 /* If the already accounted for the memory "cost" above, don't 1545 do so again. */ 1546 if (!counted_mem) 1547 { 1548 add_cost = q->mem_cost; 1549 if (add_cost > 0 && INT_MAX - add_cost < p->mem_cost) 1550 p->mem_cost = INT_MAX; 1551 else 1552 p->mem_cost += add_cost; 1553 } 1554 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 1555 { 1556 add_cost = q_costs[k]; 1557 if (add_cost > 0 && INT_MAX - add_cost < p_costs[k]) 1558 p_costs[k] = INT_MAX; 1559 else 1560 p_costs[k] += add_cost; 1561 } 1562 } 1563 } 1564 return insn; 1565 } 1566 1567 1568 1569 /* Print allocnos costs to file F. */ 1570 static void 1571 print_allocno_costs (FILE *f) 1572 { 1573 int k; 1574 ira_allocno_t a; 1575 ira_allocno_iterator ai; 1576 1577 ira_assert (allocno_p); 1578 fprintf (f, "\n"); 1579 FOR_EACH_ALLOCNO (a, ai) 1580 { 1581 int i, rclass; 1582 basic_block bb; 1583 int regno = ALLOCNO_REGNO (a); 1584 cost_classes_t cost_classes_ptr = regno_cost_classes[regno]; 1585 enum reg_class *cost_classes = cost_classes_ptr->classes; 1586 1587 i = ALLOCNO_NUM (a); 1588 fprintf (f, " a%d(r%d,", i, regno); 1589 if ((bb = ALLOCNO_LOOP_TREE_NODE (a)->bb) != NULL) 1590 fprintf (f, "b%d", bb->index); 1591 else 1592 fprintf (f, "l%d", ALLOCNO_LOOP_TREE_NODE (a)->loop_num); 1593 fprintf (f, ") costs:"); 1594 for (k = 0; k < cost_classes_ptr->num; k++) 1595 { 1596 rclass = cost_classes[k]; 1597 fprintf (f, " %s:%d", reg_class_names[rclass], 1598 COSTS (costs, i)->cost[k]); 1599 if (flag_ira_region == IRA_REGION_ALL 1600 || flag_ira_region == IRA_REGION_MIXED) 1601 fprintf (f, ",%d", COSTS (total_allocno_costs, i)->cost[k]); 1602 } 1603 fprintf (f, " MEM:%i", COSTS (costs, i)->mem_cost); 1604 if (flag_ira_region == IRA_REGION_ALL 1605 || flag_ira_region == IRA_REGION_MIXED) 1606 fprintf (f, ",%d", COSTS (total_allocno_costs, i)->mem_cost); 1607 fprintf (f, "\n"); 1608 } 1609 } 1610 1611 /* Print pseudo costs to file F. */ 1612 static void 1613 print_pseudo_costs (FILE *f) 1614 { 1615 int regno, k; 1616 int rclass; 1617 cost_classes_t cost_classes_ptr; 1618 enum reg_class *cost_classes; 1619 1620 ira_assert (! allocno_p); 1621 fprintf (f, "\n"); 1622 for (regno = max_reg_num () - 1; regno >= FIRST_PSEUDO_REGISTER; regno--) 1623 { 1624 if (REG_N_REFS (regno) <= 0) 1625 continue; 1626 cost_classes_ptr = regno_cost_classes[regno]; 1627 cost_classes = cost_classes_ptr->classes; 1628 fprintf (f, " r%d costs:", regno); 1629 for (k = 0; k < cost_classes_ptr->num; k++) 1630 { 1631 rclass = cost_classes[k]; 1632 fprintf (f, " %s:%d", reg_class_names[rclass], 1633 COSTS (costs, regno)->cost[k]); 1634 } 1635 fprintf (f, " MEM:%i\n", COSTS (costs, regno)->mem_cost); 1636 } 1637 } 1638 1639 /* Traverse the BB represented by LOOP_TREE_NODE to update the allocno 1640 costs. */ 1641 static void 1642 process_bb_for_costs (basic_block bb) 1643 { 1644 rtx_insn *insn; 1645 1646 frequency = REG_FREQ_FROM_BB (bb); 1647 if (frequency == 0) 1648 frequency = 1; 1649 FOR_BB_INSNS (bb, insn) 1650 insn = scan_one_insn (insn); 1651 } 1652 1653 /* Traverse the BB represented by LOOP_TREE_NODE to update the allocno 1654 costs. */ 1655 static void 1656 process_bb_node_for_costs (ira_loop_tree_node_t loop_tree_node) 1657 { 1658 basic_block bb; 1659 1660 bb = loop_tree_node->bb; 1661 if (bb != NULL) 1662 process_bb_for_costs (bb); 1663 } 1664 1665 /* Find costs of register classes and memory for allocnos or pseudos 1666 and their best costs. Set up preferred, alternative and allocno 1667 classes for pseudos. */ 1668 static void 1669 find_costs_and_classes (FILE *dump_file) 1670 { 1671 int i, k, start, max_cost_classes_num; 1672 int pass; 1673 basic_block bb; 1674 enum reg_class *regno_best_class, new_class; 1675 1676 init_recog (); 1677 regno_best_class 1678 = (enum reg_class *) ira_allocate (max_reg_num () 1679 * sizeof (enum reg_class)); 1680 for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--) 1681 regno_best_class[i] = NO_REGS; 1682 if (!resize_reg_info () && allocno_p 1683 && pseudo_classes_defined_p && flag_expensive_optimizations) 1684 { 1685 ira_allocno_t a; 1686 ira_allocno_iterator ai; 1687 1688 pref = pref_buffer; 1689 max_cost_classes_num = 1; 1690 FOR_EACH_ALLOCNO (a, ai) 1691 { 1692 pref[ALLOCNO_NUM (a)] = reg_preferred_class (ALLOCNO_REGNO (a)); 1693 setup_regno_cost_classes_by_aclass 1694 (ALLOCNO_REGNO (a), pref[ALLOCNO_NUM (a)]); 1695 max_cost_classes_num 1696 = MAX (max_cost_classes_num, 1697 regno_cost_classes[ALLOCNO_REGNO (a)]->num); 1698 } 1699 start = 1; 1700 } 1701 else 1702 { 1703 pref = NULL; 1704 max_cost_classes_num = ira_important_classes_num; 1705 for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--) 1706 if (regno_reg_rtx[i] != NULL_RTX) 1707 setup_regno_cost_classes_by_mode (i, PSEUDO_REGNO_MODE (i)); 1708 else 1709 setup_regno_cost_classes_by_aclass (i, ALL_REGS); 1710 start = 0; 1711 } 1712 if (allocno_p) 1713 /* Clear the flag for the next compiled function. */ 1714 pseudo_classes_defined_p = false; 1715 /* Normally we scan the insns once and determine the best class to 1716 use for each allocno. However, if -fexpensive-optimizations are 1717 on, we do so twice, the second time using the tentative best 1718 classes to guide the selection. */ 1719 for (pass = start; pass <= flag_expensive_optimizations; pass++) 1720 { 1721 if ((!allocno_p || internal_flag_ira_verbose > 0) && dump_file) 1722 fprintf (dump_file, 1723 "\nPass %i for finding pseudo/allocno costs\n\n", pass); 1724 1725 if (pass != start) 1726 { 1727 max_cost_classes_num = 1; 1728 for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--) 1729 { 1730 setup_regno_cost_classes_by_aclass (i, regno_best_class[i]); 1731 max_cost_classes_num 1732 = MAX (max_cost_classes_num, regno_cost_classes[i]->num); 1733 } 1734 } 1735 1736 struct_costs_size 1737 = sizeof (struct costs) + sizeof (int) * (max_cost_classes_num - 1); 1738 /* Zero out our accumulation of the cost of each class for each 1739 allocno. */ 1740 memset (costs, 0, cost_elements_num * struct_costs_size); 1741 1742 if (allocno_p) 1743 { 1744 /* Scan the instructions and record each time it would save code 1745 to put a certain allocno in a certain class. */ 1746 ira_traverse_loop_tree (true, ira_loop_tree_root, 1747 process_bb_node_for_costs, NULL); 1748 1749 memcpy (total_allocno_costs, costs, 1750 max_struct_costs_size * ira_allocnos_num); 1751 } 1752 else 1753 { 1754 basic_block bb; 1755 1756 FOR_EACH_BB_FN (bb, cfun) 1757 process_bb_for_costs (bb); 1758 } 1759 1760 if (pass == 0) 1761 pref = pref_buffer; 1762 1763 /* Now for each allocno look at how desirable each class is and 1764 find which class is preferred. */ 1765 for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--) 1766 { 1767 ira_allocno_t a, parent_a; 1768 int rclass, a_num, parent_a_num, add_cost; 1769 ira_loop_tree_node_t parent; 1770 int best_cost, allocno_cost; 1771 enum reg_class best, alt_class; 1772 cost_classes_t cost_classes_ptr = regno_cost_classes[i]; 1773 enum reg_class *cost_classes; 1774 int *i_costs = temp_costs->cost; 1775 int i_mem_cost; 1776 int equiv_savings = regno_equiv_gains[i]; 1777 1778 if (! allocno_p) 1779 { 1780 if (regno_reg_rtx[i] == NULL_RTX) 1781 continue; 1782 memcpy (temp_costs, COSTS (costs, i), struct_costs_size); 1783 i_mem_cost = temp_costs->mem_cost; 1784 cost_classes = cost_classes_ptr->classes; 1785 } 1786 else 1787 { 1788 if (ira_regno_allocno_map[i] == NULL) 1789 continue; 1790 memset (temp_costs, 0, struct_costs_size); 1791 i_mem_cost = 0; 1792 cost_classes = cost_classes_ptr->classes; 1793 /* Find cost of all allocnos with the same regno. */ 1794 for (a = ira_regno_allocno_map[i]; 1795 a != NULL; 1796 a = ALLOCNO_NEXT_REGNO_ALLOCNO (a)) 1797 { 1798 int *a_costs, *p_costs; 1799 1800 a_num = ALLOCNO_NUM (a); 1801 if ((flag_ira_region == IRA_REGION_ALL 1802 || flag_ira_region == IRA_REGION_MIXED) 1803 && (parent = ALLOCNO_LOOP_TREE_NODE (a)->parent) != NULL 1804 && (parent_a = parent->regno_allocno_map[i]) != NULL 1805 /* There are no caps yet. */ 1806 && bitmap_bit_p (ALLOCNO_LOOP_TREE_NODE 1807 (a)->border_allocnos, 1808 ALLOCNO_NUM (a))) 1809 { 1810 /* Propagate costs to upper levels in the region 1811 tree. */ 1812 parent_a_num = ALLOCNO_NUM (parent_a); 1813 a_costs = COSTS (total_allocno_costs, a_num)->cost; 1814 p_costs = COSTS (total_allocno_costs, parent_a_num)->cost; 1815 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 1816 { 1817 add_cost = a_costs[k]; 1818 if (add_cost > 0 && INT_MAX - add_cost < p_costs[k]) 1819 p_costs[k] = INT_MAX; 1820 else 1821 p_costs[k] += add_cost; 1822 } 1823 add_cost = COSTS (total_allocno_costs, a_num)->mem_cost; 1824 if (add_cost > 0 1825 && (INT_MAX - add_cost 1826 < COSTS (total_allocno_costs, 1827 parent_a_num)->mem_cost)) 1828 COSTS (total_allocno_costs, parent_a_num)->mem_cost 1829 = INT_MAX; 1830 else 1831 COSTS (total_allocno_costs, parent_a_num)->mem_cost 1832 += add_cost; 1833 1834 if (i >= first_moveable_pseudo && i < last_moveable_pseudo) 1835 COSTS (total_allocno_costs, parent_a_num)->mem_cost = 0; 1836 } 1837 a_costs = COSTS (costs, a_num)->cost; 1838 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 1839 { 1840 add_cost = a_costs[k]; 1841 if (add_cost > 0 && INT_MAX - add_cost < i_costs[k]) 1842 i_costs[k] = INT_MAX; 1843 else 1844 i_costs[k] += add_cost; 1845 } 1846 add_cost = COSTS (costs, a_num)->mem_cost; 1847 if (add_cost > 0 && INT_MAX - add_cost < i_mem_cost) 1848 i_mem_cost = INT_MAX; 1849 else 1850 i_mem_cost += add_cost; 1851 } 1852 } 1853 if (i >= first_moveable_pseudo && i < last_moveable_pseudo) 1854 i_mem_cost = 0; 1855 else if (equiv_savings < 0) 1856 i_mem_cost = -equiv_savings; 1857 else if (equiv_savings > 0) 1858 { 1859 i_mem_cost = 0; 1860 for (k = cost_classes_ptr->num - 1; k >= 0; k--) 1861 i_costs[k] += equiv_savings; 1862 } 1863 1864 best_cost = (1 << (HOST_BITS_PER_INT - 2)) - 1; 1865 best = ALL_REGS; 1866 alt_class = NO_REGS; 1867 /* Find best common class for all allocnos with the same 1868 regno. */ 1869 for (k = 0; k < cost_classes_ptr->num; k++) 1870 { 1871 rclass = cost_classes[k]; 1872 if (i_costs[k] < best_cost) 1873 { 1874 best_cost = i_costs[k]; 1875 best = (enum reg_class) rclass; 1876 } 1877 else if (i_costs[k] == best_cost) 1878 best = ira_reg_class_subunion[best][rclass]; 1879 if (pass == flag_expensive_optimizations 1880 /* We still prefer registers to memory even at this 1881 stage if their costs are the same. We will make 1882 a final decision during assigning hard registers 1883 when we have all info including more accurate 1884 costs which might be affected by assigning hard 1885 registers to other pseudos because the pseudos 1886 involved in moves can be coalesced. */ 1887 && i_costs[k] <= i_mem_cost 1888 && (reg_class_size[reg_class_subunion[alt_class][rclass]] 1889 > reg_class_size[alt_class])) 1890 alt_class = reg_class_subunion[alt_class][rclass]; 1891 } 1892 alt_class = ira_allocno_class_translate[alt_class]; 1893 if (best_cost > i_mem_cost 1894 && ! non_spilled_static_chain_regno_p (i)) 1895 regno_aclass[i] = NO_REGS; 1896 else if (!optimize && !targetm.class_likely_spilled_p (best)) 1897 /* Registers in the alternative class are likely to need 1898 longer or slower sequences than registers in the best class. 1899 When optimizing we make some effort to use the best class 1900 over the alternative class where possible, but at -O0 we 1901 effectively give the alternative class equal weight. 1902 We then run the risk of using slower alternative registers 1903 when plenty of registers from the best class are still free. 1904 This is especially true because live ranges tend to be very 1905 short in -O0 code and so register pressure tends to be low. 1906 1907 Avoid that by ignoring the alternative class if the best 1908 class has plenty of registers. 1909 1910 The union class arrays give important classes and only 1911 part of it are allocno classes. So translate them into 1912 allocno classes. */ 1913 regno_aclass[i] = ira_allocno_class_translate[best]; 1914 else 1915 { 1916 /* Make the common class the biggest class of best and 1917 alt_class. Translate the common class into an 1918 allocno class too. */ 1919 regno_aclass[i] = (ira_allocno_class_translate 1920 [ira_reg_class_superunion[best][alt_class]]); 1921 ira_assert (regno_aclass[i] != NO_REGS 1922 && ira_reg_allocno_class_p[regno_aclass[i]]); 1923 } 1924 if ((new_class 1925 = (reg_class) (targetm.ira_change_pseudo_allocno_class 1926 (i, regno_aclass[i], best))) != regno_aclass[i]) 1927 { 1928 regno_aclass[i] = new_class; 1929 if (hard_reg_set_subset_p (reg_class_contents[new_class], 1930 reg_class_contents[best])) 1931 best = new_class; 1932 if (hard_reg_set_subset_p (reg_class_contents[new_class], 1933 reg_class_contents[alt_class])) 1934 alt_class = new_class; 1935 } 1936 if (pass == flag_expensive_optimizations) 1937 { 1938 if (best_cost > i_mem_cost 1939 /* Do not assign NO_REGS to static chain pointer 1940 pseudo when non-local goto is used. */ 1941 && ! non_spilled_static_chain_regno_p (i)) 1942 best = alt_class = NO_REGS; 1943 else if (best == alt_class) 1944 alt_class = NO_REGS; 1945 setup_reg_classes (i, best, alt_class, regno_aclass[i]); 1946 if ((!allocno_p || internal_flag_ira_verbose > 2) 1947 && dump_file != NULL) 1948 fprintf (dump_file, 1949 " r%d: preferred %s, alternative %s, allocno %s\n", 1950 i, reg_class_names[best], reg_class_names[alt_class], 1951 reg_class_names[regno_aclass[i]]); 1952 } 1953 regno_best_class[i] = best; 1954 if (! allocno_p) 1955 { 1956 pref[i] = (best_cost > i_mem_cost 1957 && ! non_spilled_static_chain_regno_p (i) 1958 ? NO_REGS : best); 1959 continue; 1960 } 1961 for (a = ira_regno_allocno_map[i]; 1962 a != NULL; 1963 a = ALLOCNO_NEXT_REGNO_ALLOCNO (a)) 1964 { 1965 enum reg_class aclass = regno_aclass[i]; 1966 int a_num = ALLOCNO_NUM (a); 1967 int *total_a_costs = COSTS (total_allocno_costs, a_num)->cost; 1968 int *a_costs = COSTS (costs, a_num)->cost; 1969 1970 if (aclass == NO_REGS) 1971 best = NO_REGS; 1972 else 1973 { 1974 /* Finding best class which is subset of the common 1975 class. */ 1976 best_cost = (1 << (HOST_BITS_PER_INT - 2)) - 1; 1977 allocno_cost = best_cost; 1978 best = ALL_REGS; 1979 for (k = 0; k < cost_classes_ptr->num; k++) 1980 { 1981 rclass = cost_classes[k]; 1982 if (! ira_class_subset_p[rclass][aclass]) 1983 continue; 1984 if (total_a_costs[k] < best_cost) 1985 { 1986 best_cost = total_a_costs[k]; 1987 allocno_cost = a_costs[k]; 1988 best = (enum reg_class) rclass; 1989 } 1990 else if (total_a_costs[k] == best_cost) 1991 { 1992 best = ira_reg_class_subunion[best][rclass]; 1993 allocno_cost = MAX (allocno_cost, a_costs[k]); 1994 } 1995 } 1996 ALLOCNO_CLASS_COST (a) = allocno_cost; 1997 } 1998 if (internal_flag_ira_verbose > 2 && dump_file != NULL 1999 && (pass == 0 || pref[a_num] != best)) 2000 { 2001 fprintf (dump_file, " a%d (r%d,", a_num, i); 2002 if ((bb = ALLOCNO_LOOP_TREE_NODE (a)->bb) != NULL) 2003 fprintf (dump_file, "b%d", bb->index); 2004 else 2005 fprintf (dump_file, "l%d", 2006 ALLOCNO_LOOP_TREE_NODE (a)->loop_num); 2007 fprintf (dump_file, ") best %s, allocno %s\n", 2008 reg_class_names[best], 2009 reg_class_names[aclass]); 2010 } 2011 pref[a_num] = best; 2012 if (pass == flag_expensive_optimizations && best != aclass 2013 && ira_class_hard_regs_num[best] > 0 2014 && (ira_reg_class_max_nregs[best][ALLOCNO_MODE (a)] 2015 >= ira_class_hard_regs_num[best])) 2016 { 2017 int ind = cost_classes_ptr->index[aclass]; 2018 2019 ira_assert (ind >= 0); 2020 ira_init_register_move_cost_if_necessary (ALLOCNO_MODE (a)); 2021 ira_add_allocno_pref (a, ira_class_hard_regs[best][0], 2022 (a_costs[ind] - ALLOCNO_CLASS_COST (a)) 2023 / (ira_register_move_cost 2024 [ALLOCNO_MODE (a)][best][aclass])); 2025 for (k = 0; k < cost_classes_ptr->num; k++) 2026 if (ira_class_subset_p[cost_classes[k]][best]) 2027 a_costs[k] = a_costs[ind]; 2028 } 2029 } 2030 } 2031 2032 if (internal_flag_ira_verbose > 4 && dump_file) 2033 { 2034 if (allocno_p) 2035 print_allocno_costs (dump_file); 2036 else 2037 print_pseudo_costs (dump_file); 2038 fprintf (dump_file,"\n"); 2039 } 2040 } 2041 ira_free (regno_best_class); 2042 } 2043 2044 2045 2046 /* Process moves involving hard regs to modify allocno hard register 2047 costs. We can do this only after determining allocno class. If a 2048 hard register forms a register class, then moves with the hard 2049 register are already taken into account in class costs for the 2050 allocno. */ 2051 static void 2052 process_bb_node_for_hard_reg_moves (ira_loop_tree_node_t loop_tree_node) 2053 { 2054 int i, freq, src_regno, dst_regno, hard_regno, a_regno; 2055 bool to_p; 2056 ira_allocno_t a, curr_a; 2057 ira_loop_tree_node_t curr_loop_tree_node; 2058 enum reg_class rclass; 2059 basic_block bb; 2060 rtx_insn *insn; 2061 rtx set, src, dst; 2062 2063 bb = loop_tree_node->bb; 2064 if (bb == NULL) 2065 return; 2066 freq = REG_FREQ_FROM_BB (bb); 2067 if (freq == 0) 2068 freq = 1; 2069 FOR_BB_INSNS (bb, insn) 2070 { 2071 if (!NONDEBUG_INSN_P (insn)) 2072 continue; 2073 set = single_set (insn); 2074 if (set == NULL_RTX) 2075 continue; 2076 dst = SET_DEST (set); 2077 src = SET_SRC (set); 2078 if (! REG_P (dst) || ! REG_P (src)) 2079 continue; 2080 dst_regno = REGNO (dst); 2081 src_regno = REGNO (src); 2082 if (dst_regno >= FIRST_PSEUDO_REGISTER 2083 && src_regno < FIRST_PSEUDO_REGISTER) 2084 { 2085 hard_regno = src_regno; 2086 a = ira_curr_regno_allocno_map[dst_regno]; 2087 to_p = true; 2088 } 2089 else if (src_regno >= FIRST_PSEUDO_REGISTER 2090 && dst_regno < FIRST_PSEUDO_REGISTER) 2091 { 2092 hard_regno = dst_regno; 2093 a = ira_curr_regno_allocno_map[src_regno]; 2094 to_p = false; 2095 } 2096 else 2097 continue; 2098 if (reg_class_size[(int) REGNO_REG_CLASS (hard_regno)] 2099 == (ira_reg_class_max_nregs 2100 [REGNO_REG_CLASS (hard_regno)][(int) ALLOCNO_MODE(a)])) 2101 /* If the class can provide only one hard reg to the allocno, 2102 we processed the insn record_operand_costs already and we 2103 actually updated the hard reg cost there. */ 2104 continue; 2105 rclass = ALLOCNO_CLASS (a); 2106 if (! TEST_HARD_REG_BIT (reg_class_contents[rclass], hard_regno)) 2107 continue; 2108 i = ira_class_hard_reg_index[rclass][hard_regno]; 2109 if (i < 0) 2110 continue; 2111 a_regno = ALLOCNO_REGNO (a); 2112 for (curr_loop_tree_node = ALLOCNO_LOOP_TREE_NODE (a); 2113 curr_loop_tree_node != NULL; 2114 curr_loop_tree_node = curr_loop_tree_node->parent) 2115 if ((curr_a = curr_loop_tree_node->regno_allocno_map[a_regno]) != NULL) 2116 ira_add_allocno_pref (curr_a, hard_regno, freq); 2117 { 2118 int cost; 2119 enum reg_class hard_reg_class; 2120 machine_mode mode; 2121 2122 mode = ALLOCNO_MODE (a); 2123 hard_reg_class = REGNO_REG_CLASS (hard_regno); 2124 ira_init_register_move_cost_if_necessary (mode); 2125 cost = (to_p ? ira_register_move_cost[mode][hard_reg_class][rclass] 2126 : ira_register_move_cost[mode][rclass][hard_reg_class]) * freq; 2127 ira_allocate_and_set_costs (&ALLOCNO_HARD_REG_COSTS (a), rclass, 2128 ALLOCNO_CLASS_COST (a)); 2129 ira_allocate_and_set_costs (&ALLOCNO_CONFLICT_HARD_REG_COSTS (a), 2130 rclass, 0); 2131 ALLOCNO_HARD_REG_COSTS (a)[i] -= cost; 2132 ALLOCNO_CONFLICT_HARD_REG_COSTS (a)[i] -= cost; 2133 ALLOCNO_CLASS_COST (a) = MIN (ALLOCNO_CLASS_COST (a), 2134 ALLOCNO_HARD_REG_COSTS (a)[i]); 2135 } 2136 } 2137 } 2138 2139 /* After we find hard register and memory costs for allocnos, define 2140 its class and modify hard register cost because insns moving 2141 allocno to/from hard registers. */ 2142 static void 2143 setup_allocno_class_and_costs (void) 2144 { 2145 int i, j, n, regno, hard_regno, num; 2146 int *reg_costs; 2147 enum reg_class aclass, rclass; 2148 ira_allocno_t a; 2149 ira_allocno_iterator ai; 2150 cost_classes_t cost_classes_ptr; 2151 2152 ira_assert (allocno_p); 2153 FOR_EACH_ALLOCNO (a, ai) 2154 { 2155 i = ALLOCNO_NUM (a); 2156 regno = ALLOCNO_REGNO (a); 2157 aclass = regno_aclass[regno]; 2158 cost_classes_ptr = regno_cost_classes[regno]; 2159 ira_assert (pref[i] == NO_REGS || aclass != NO_REGS); 2160 ALLOCNO_MEMORY_COST (a) = COSTS (costs, i)->mem_cost; 2161 ira_set_allocno_class (a, aclass); 2162 if (aclass == NO_REGS) 2163 continue; 2164 if (optimize && ALLOCNO_CLASS (a) != pref[i]) 2165 { 2166 n = ira_class_hard_regs_num[aclass]; 2167 ALLOCNO_HARD_REG_COSTS (a) 2168 = reg_costs = ira_allocate_cost_vector (aclass); 2169 for (j = n - 1; j >= 0; j--) 2170 { 2171 hard_regno = ira_class_hard_regs[aclass][j]; 2172 if (TEST_HARD_REG_BIT (reg_class_contents[pref[i]], hard_regno)) 2173 reg_costs[j] = ALLOCNO_CLASS_COST (a); 2174 else 2175 { 2176 rclass = REGNO_REG_CLASS (hard_regno); 2177 num = cost_classes_ptr->index[rclass]; 2178 if (num < 0) 2179 { 2180 num = cost_classes_ptr->hard_regno_index[hard_regno]; 2181 ira_assert (num >= 0); 2182 } 2183 reg_costs[j] = COSTS (costs, i)->cost[num]; 2184 } 2185 } 2186 } 2187 } 2188 if (optimize) 2189 ira_traverse_loop_tree (true, ira_loop_tree_root, 2190 process_bb_node_for_hard_reg_moves, NULL); 2191 } 2192 2193 2194 2195 /* Function called once during compiler work. */ 2196 void 2197 ira_init_costs_once (void) 2198 { 2199 int i; 2200 2201 init_cost = NULL; 2202 for (i = 0; i < MAX_RECOG_OPERANDS; i++) 2203 { 2204 op_costs[i] = NULL; 2205 this_op_costs[i] = NULL; 2206 } 2207 temp_costs = NULL; 2208 } 2209 2210 /* Free allocated temporary cost vectors. */ 2211 void 2212 target_ira_int::free_ira_costs () 2213 { 2214 int i; 2215 2216 free (x_init_cost); 2217 x_init_cost = NULL; 2218 for (i = 0; i < MAX_RECOG_OPERANDS; i++) 2219 { 2220 free (x_op_costs[i]); 2221 free (x_this_op_costs[i]); 2222 x_op_costs[i] = x_this_op_costs[i] = NULL; 2223 } 2224 free (x_temp_costs); 2225 x_temp_costs = NULL; 2226 } 2227 2228 /* This is called each time register related information is 2229 changed. */ 2230 void 2231 ira_init_costs (void) 2232 { 2233 int i; 2234 2235 this_target_ira_int->free_ira_costs (); 2236 max_struct_costs_size 2237 = sizeof (struct costs) + sizeof (int) * (ira_important_classes_num - 1); 2238 /* Don't use ira_allocate because vectors live through several IRA 2239 calls. */ 2240 init_cost = (struct costs *) xmalloc (max_struct_costs_size); 2241 init_cost->mem_cost = 1000000; 2242 for (i = 0; i < ira_important_classes_num; i++) 2243 init_cost->cost[i] = 1000000; 2244 for (i = 0; i < MAX_RECOG_OPERANDS; i++) 2245 { 2246 op_costs[i] = (struct costs *) xmalloc (max_struct_costs_size); 2247 this_op_costs[i] = (struct costs *) xmalloc (max_struct_costs_size); 2248 } 2249 temp_costs = (struct costs *) xmalloc (max_struct_costs_size); 2250 } 2251 2252 2253 2254 /* Common initialization function for ira_costs and 2255 ira_set_pseudo_classes. */ 2256 static void 2257 init_costs (void) 2258 { 2259 init_subregs_of_mode (); 2260 costs = (struct costs *) ira_allocate (max_struct_costs_size 2261 * cost_elements_num); 2262 pref_buffer = (enum reg_class *) ira_allocate (sizeof (enum reg_class) 2263 * cost_elements_num); 2264 regno_aclass = (enum reg_class *) ira_allocate (sizeof (enum reg_class) 2265 * max_reg_num ()); 2266 regno_equiv_gains = (int *) ira_allocate (sizeof (int) * max_reg_num ()); 2267 memset (regno_equiv_gains, 0, sizeof (int) * max_reg_num ()); 2268 } 2269 2270 /* Common finalization function for ira_costs and 2271 ira_set_pseudo_classes. */ 2272 static void 2273 finish_costs (void) 2274 { 2275 finish_subregs_of_mode (); 2276 ira_free (regno_equiv_gains); 2277 ira_free (regno_aclass); 2278 ira_free (pref_buffer); 2279 ira_free (costs); 2280 } 2281 2282 /* Entry function which defines register class, memory and hard 2283 register costs for each allocno. */ 2284 void 2285 ira_costs (void) 2286 { 2287 allocno_p = true; 2288 cost_elements_num = ira_allocnos_num; 2289 init_costs (); 2290 total_allocno_costs = (struct costs *) ira_allocate (max_struct_costs_size 2291 * ira_allocnos_num); 2292 initiate_regno_cost_classes (); 2293 calculate_elim_costs_all_insns (); 2294 find_costs_and_classes (ira_dump_file); 2295 setup_allocno_class_and_costs (); 2296 finish_regno_cost_classes (); 2297 finish_costs (); 2298 ira_free (total_allocno_costs); 2299 } 2300 2301 /* Entry function which defines classes for pseudos. 2302 Set pseudo_classes_defined_p only if DEFINE_PSEUDO_CLASSES is true. */ 2303 void 2304 ira_set_pseudo_classes (bool define_pseudo_classes, FILE *dump_file) 2305 { 2306 allocno_p = false; 2307 internal_flag_ira_verbose = flag_ira_verbose; 2308 cost_elements_num = max_reg_num (); 2309 init_costs (); 2310 initiate_regno_cost_classes (); 2311 find_costs_and_classes (dump_file); 2312 finish_regno_cost_classes (); 2313 if (define_pseudo_classes) 2314 pseudo_classes_defined_p = true; 2315 2316 finish_costs (); 2317 } 2318 2319 2320 2321 /* Change hard register costs for allocnos which lives through 2322 function calls. This is called only when we found all intersected 2323 calls during building allocno live ranges. */ 2324 void 2325 ira_tune_allocno_costs (void) 2326 { 2327 int j, n, regno; 2328 int cost, min_cost, *reg_costs; 2329 enum reg_class aclass, rclass; 2330 machine_mode mode; 2331 ira_allocno_t a; 2332 ira_allocno_iterator ai; 2333 ira_allocno_object_iterator oi; 2334 ira_object_t obj; 2335 bool skip_p; 2336 2337 FOR_EACH_ALLOCNO (a, ai) 2338 { 2339 aclass = ALLOCNO_CLASS (a); 2340 if (aclass == NO_REGS) 2341 continue; 2342 mode = ALLOCNO_MODE (a); 2343 n = ira_class_hard_regs_num[aclass]; 2344 min_cost = INT_MAX; 2345 if (ALLOCNO_CALLS_CROSSED_NUM (a) 2346 != ALLOCNO_CHEAP_CALLS_CROSSED_NUM (a)) 2347 { 2348 ira_allocate_and_set_costs 2349 (&ALLOCNO_HARD_REG_COSTS (a), aclass, 2350 ALLOCNO_CLASS_COST (a)); 2351 reg_costs = ALLOCNO_HARD_REG_COSTS (a); 2352 for (j = n - 1; j >= 0; j--) 2353 { 2354 regno = ira_class_hard_regs[aclass][j]; 2355 skip_p = false; 2356 FOR_EACH_ALLOCNO_OBJECT (a, obj, oi) 2357 { 2358 if (ira_hard_reg_set_intersection_p (regno, mode, 2359 OBJECT_CONFLICT_HARD_REGS 2360 (obj))) 2361 { 2362 skip_p = true; 2363 break; 2364 } 2365 } 2366 if (skip_p) 2367 continue; 2368 rclass = REGNO_REG_CLASS (regno); 2369 cost = 0; 2370 if (ira_need_caller_save_p (a, regno)) 2371 cost += (ALLOCNO_CALL_FREQ (a) 2372 * (ira_memory_move_cost[mode][rclass][0] 2373 + ira_memory_move_cost[mode][rclass][1])); 2374 #ifdef IRA_HARD_REGNO_ADD_COST_MULTIPLIER 2375 cost += ((ira_memory_move_cost[mode][rclass][0] 2376 + ira_memory_move_cost[mode][rclass][1]) 2377 * ALLOCNO_FREQ (a) 2378 * IRA_HARD_REGNO_ADD_COST_MULTIPLIER (regno) / 2); 2379 #endif 2380 if (INT_MAX - cost < reg_costs[j]) 2381 reg_costs[j] = INT_MAX; 2382 else 2383 reg_costs[j] += cost; 2384 if (min_cost > reg_costs[j]) 2385 min_cost = reg_costs[j]; 2386 } 2387 } 2388 if (min_cost != INT_MAX) 2389 ALLOCNO_CLASS_COST (a) = min_cost; 2390 2391 /* Some targets allow pseudos to be allocated to unaligned sequences 2392 of hard registers. However, selecting an unaligned sequence can 2393 unnecessarily restrict later allocations. So increase the cost of 2394 unaligned hard regs to encourage the use of aligned hard regs. */ 2395 { 2396 const int nregs = ira_reg_class_max_nregs[aclass][ALLOCNO_MODE (a)]; 2397 2398 if (nregs > 1) 2399 { 2400 ira_allocate_and_set_costs 2401 (&ALLOCNO_HARD_REG_COSTS (a), aclass, ALLOCNO_CLASS_COST (a)); 2402 reg_costs = ALLOCNO_HARD_REG_COSTS (a); 2403 for (j = n - 1; j >= 0; j--) 2404 { 2405 regno = ira_non_ordered_class_hard_regs[aclass][j]; 2406 if ((regno % nregs) != 0) 2407 { 2408 int index = ira_class_hard_reg_index[aclass][regno]; 2409 ira_assert (index != -1); 2410 reg_costs[index] += ALLOCNO_FREQ (a); 2411 } 2412 } 2413 } 2414 } 2415 } 2416 } 2417 2418 /* Add COST to the estimated gain for eliminating REGNO with its 2419 equivalence. If COST is zero, record that no such elimination is 2420 possible. */ 2421 2422 void 2423 ira_adjust_equiv_reg_cost (unsigned regno, int cost) 2424 { 2425 if (cost == 0) 2426 regno_equiv_gains[regno] = 0; 2427 else 2428 regno_equiv_gains[regno] += cost; 2429 } 2430 2431 void 2432 ira_costs_c_finalize (void) 2433 { 2434 this_target_ira_int->free_ira_costs (); 2435 } 2436