1/* Search an insn for pseudo regs that must be in hard regs and are not. 2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, 4 Inc. 5 6This file is part of GCC. 7 8GCC is free software; you can redistribute it and/or modify it under 9the terms of the GNU General Public License as published by the Free 10Software Foundation; either version 2, or (at your option) any later 11version. 12 13GCC is distributed in the hope that it will be useful, but WITHOUT ANY 14WARRANTY; without even the implied warranty of MERCHANTABILITY or 15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 16for more details. 17 18You should have received a copy of the GNU General Public License 19along with GCC; see the file COPYING. If not, write to the Free 20Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 2102110-1301, USA. */ 22 23/* This file contains subroutines used only from the file reload1.c. 24 It knows how to scan one insn for operands and values 25 that need to be copied into registers to make valid code. 26 It also finds other operands and values which are valid 27 but for which equivalent values in registers exist and 28 ought to be used instead. 29 30 Before processing the first insn of the function, call `init_reload'. 31 init_reload actually has to be called earlier anyway. 32 33 To scan an insn, call `find_reloads'. This does two things: 34 1. sets up tables describing which values must be reloaded 35 for this insn, and what kind of hard regs they must be reloaded into; 36 2. optionally record the locations where those values appear in 37 the data, so they can be replaced properly later. 38 This is done only if the second arg to `find_reloads' is nonzero. 39 40 The third arg to `find_reloads' specifies the number of levels 41 of indirect addressing supported by the machine. If it is zero, 42 indirect addressing is not valid. If it is one, (MEM (REG n)) 43 is valid even if (REG n) did not get a hard register; if it is two, 44 (MEM (MEM (REG n))) is also valid even if (REG n) did not get a 45 hard register, and similarly for higher values. 46 47 Then you must choose the hard regs to reload those pseudo regs into, 48 and generate appropriate load insns before this insn and perhaps 49 also store insns after this insn. Set up the array `reload_reg_rtx' 50 to contain the REG rtx's for the registers you used. In some 51 cases `find_reloads' will return a nonzero value in `reload_reg_rtx' 52 for certain reloads. Then that tells you which register to use, 53 so you do not need to allocate one. But you still do need to add extra 54 instructions to copy the value into and out of that register. 55 56 Finally you must call `subst_reloads' to substitute the reload reg rtx's 57 into the locations already recorded. 58 59NOTE SIDE EFFECTS: 60 61 find_reloads can alter the operands of the instruction it is called on. 62 63 1. Two operands of any sort may be interchanged, if they are in a 64 commutative instruction. 65 This happens only if find_reloads thinks the instruction will compile 66 better that way. 67 68 2. Pseudo-registers that are equivalent to constants are replaced 69 with those constants if they are not in hard registers. 70 711 happens every time find_reloads is called. 722 happens only when REPLACE is 1, which is only when 73actually doing the reloads, not when just counting them. 74 75Using a reload register for several reloads in one insn: 76 77When an insn has reloads, it is considered as having three parts: 78the input reloads, the insn itself after reloading, and the output reloads. 79Reloads of values used in memory addresses are often needed for only one part. 80 81When this is so, reload_when_needed records which part needs the reload. 82Two reloads for different parts of the insn can share the same reload 83register. 84 85When a reload is used for addresses in multiple parts, or when it is 86an ordinary operand, it is classified as RELOAD_OTHER, and cannot share 87a register with any other reload. */ 88 89#define REG_OK_STRICT 90 91#include "config.h" 92#include "system.h" 93#include "coretypes.h" 94#include "tm.h" 95#include "rtl.h" 96#include "tm_p.h" 97#include "insn-config.h" 98#include "expr.h" 99#include "optabs.h" 100#include "recog.h" 101#include "reload.h" 102#include "regs.h" 103#include "addresses.h" 104#include "hard-reg-set.h" 105#include "flags.h" 106#include "real.h" 107#include "output.h" 108#include "function.h" 109#include "toplev.h" 110#include "params.h" 111#include "target.h" 112 113/* True if X is a constant that can be forced into the constant pool. */ 114#define CONST_POOL_OK_P(X) \ 115 (CONSTANT_P (X) \ 116 && GET_CODE (X) != HIGH \ 117 && !targetm.cannot_force_const_mem (X)) 118 119/* True if C is a non-empty register class that has too few registers 120 to be safely used as a reload target class. */ 121#define SMALL_REGISTER_CLASS_P(C) \ 122 (reg_class_size [(C)] == 1 \ 123 || (reg_class_size [(C)] >= 1 && CLASS_LIKELY_SPILLED_P (C))) 124 125 126/* All reloads of the current insn are recorded here. See reload.h for 127 comments. */ 128int n_reloads; 129struct reload rld[MAX_RELOADS]; 130 131/* All the "earlyclobber" operands of the current insn 132 are recorded here. */ 133int n_earlyclobbers; 134rtx reload_earlyclobbers[MAX_RECOG_OPERANDS]; 135 136int reload_n_operands; 137 138/* Replacing reloads. 139 140 If `replace_reloads' is nonzero, then as each reload is recorded 141 an entry is made for it in the table `replacements'. 142 Then later `subst_reloads' can look through that table and 143 perform all the replacements needed. */ 144 145/* Nonzero means record the places to replace. */ 146static int replace_reloads; 147 148/* Each replacement is recorded with a structure like this. */ 149struct replacement 150{ 151 rtx *where; /* Location to store in */ 152 rtx *subreg_loc; /* Location of SUBREG if WHERE is inside 153 a SUBREG; 0 otherwise. */ 154 int what; /* which reload this is for */ 155 enum machine_mode mode; /* mode it must have */ 156}; 157 158static struct replacement replacements[MAX_RECOG_OPERANDS * ((MAX_REGS_PER_ADDRESS * 2) + 1)]; 159 160/* Number of replacements currently recorded. */ 161static int n_replacements; 162 163/* Used to track what is modified by an operand. */ 164struct decomposition 165{ 166 int reg_flag; /* Nonzero if referencing a register. */ 167 int safe; /* Nonzero if this can't conflict with anything. */ 168 rtx base; /* Base address for MEM. */ 169 HOST_WIDE_INT start; /* Starting offset or register number. */ 170 HOST_WIDE_INT end; /* Ending offset or register number. */ 171}; 172 173#ifdef SECONDARY_MEMORY_NEEDED 174 175/* Save MEMs needed to copy from one class of registers to another. One MEM 176 is used per mode, but normally only one or two modes are ever used. 177 178 We keep two versions, before and after register elimination. The one 179 after register elimination is record separately for each operand. This 180 is done in case the address is not valid to be sure that we separately 181 reload each. */ 182 183static rtx secondary_memlocs[NUM_MACHINE_MODES]; 184static rtx secondary_memlocs_elim[NUM_MACHINE_MODES][MAX_RECOG_OPERANDS]; 185static int secondary_memlocs_elim_used = 0; 186#endif 187 188/* The instruction we are doing reloads for; 189 so we can test whether a register dies in it. */ 190static rtx this_insn; 191 192/* Nonzero if this instruction is a user-specified asm with operands. */ 193static int this_insn_is_asm; 194 195/* If hard_regs_live_known is nonzero, 196 we can tell which hard regs are currently live, 197 at least enough to succeed in choosing dummy reloads. */ 198static int hard_regs_live_known; 199 200/* Indexed by hard reg number, 201 element is nonnegative if hard reg has been spilled. 202 This vector is passed to `find_reloads' as an argument 203 and is not changed here. */ 204static short *static_reload_reg_p; 205 206/* Set to 1 in subst_reg_equivs if it changes anything. */ 207static int subst_reg_equivs_changed; 208 209/* On return from push_reload, holds the reload-number for the OUT 210 operand, which can be different for that from the input operand. */ 211static int output_reloadnum; 212 213 /* Compare two RTX's. */ 214#define MATCHES(x, y) \ 215 (x == y || (x != 0 && (REG_P (x) \ 216 ? REG_P (y) && REGNO (x) == REGNO (y) \ 217 : rtx_equal_p (x, y) && ! side_effects_p (x)))) 218 219 /* Indicates if two reloads purposes are for similar enough things that we 220 can merge their reloads. */ 221#define MERGABLE_RELOADS(when1, when2, op1, op2) \ 222 ((when1) == RELOAD_OTHER || (when2) == RELOAD_OTHER \ 223 || ((when1) == (when2) && (op1) == (op2)) \ 224 || ((when1) == RELOAD_FOR_INPUT && (when2) == RELOAD_FOR_INPUT) \ 225 || ((when1) == RELOAD_FOR_OPERAND_ADDRESS \ 226 && (when2) == RELOAD_FOR_OPERAND_ADDRESS) \ 227 || ((when1) == RELOAD_FOR_OTHER_ADDRESS \ 228 && (when2) == RELOAD_FOR_OTHER_ADDRESS)) 229 230 /* Nonzero if these two reload purposes produce RELOAD_OTHER when merged. */ 231#define MERGE_TO_OTHER(when1, when2, op1, op2) \ 232 ((when1) != (when2) \ 233 || ! ((op1) == (op2) \ 234 || (when1) == RELOAD_FOR_INPUT \ 235 || (when1) == RELOAD_FOR_OPERAND_ADDRESS \ 236 || (when1) == RELOAD_FOR_OTHER_ADDRESS)) 237 238 /* If we are going to reload an address, compute the reload type to 239 use. */ 240#define ADDR_TYPE(type) \ 241 ((type) == RELOAD_FOR_INPUT_ADDRESS \ 242 ? RELOAD_FOR_INPADDR_ADDRESS \ 243 : ((type) == RELOAD_FOR_OUTPUT_ADDRESS \ 244 ? RELOAD_FOR_OUTADDR_ADDRESS \ 245 : (type))) 246 247static int push_secondary_reload (int, rtx, int, int, enum reg_class, 248 enum machine_mode, enum reload_type, 249 enum insn_code *, secondary_reload_info *); 250static enum reg_class find_valid_class (enum machine_mode, enum machine_mode, 251 int, unsigned int); 252static int reload_inner_reg_of_subreg (rtx, enum machine_mode, int); 253static void push_replacement (rtx *, int, enum machine_mode); 254static void dup_replacements (rtx *, rtx *); 255static void combine_reloads (void); 256static int find_reusable_reload (rtx *, rtx, enum reg_class, 257 enum reload_type, int, int); 258static rtx find_dummy_reload (rtx, rtx, rtx *, rtx *, enum machine_mode, 259 enum machine_mode, enum reg_class, int, int); 260static int hard_reg_set_here_p (unsigned int, unsigned int, rtx); 261static struct decomposition decompose (rtx); 262static int immune_p (rtx, rtx, struct decomposition); 263static int alternative_allows_memconst (const char *, int); 264static rtx find_reloads_toplev (rtx, int, enum reload_type, int, int, rtx, 265 int *); 266static rtx make_memloc (rtx, int); 267static int maybe_memory_address_p (enum machine_mode, rtx, rtx *); 268static int find_reloads_address (enum machine_mode, rtx *, rtx, rtx *, 269 int, enum reload_type, int, rtx); 270static rtx subst_reg_equivs (rtx, rtx); 271static rtx subst_indexed_address (rtx); 272static void update_auto_inc_notes (rtx, int, int); 273static int find_reloads_address_1 (enum machine_mode, rtx, int, 274 enum rtx_code, enum rtx_code, rtx *, 275 int, enum reload_type,int, rtx); 276static void find_reloads_address_part (rtx, rtx *, enum reg_class, 277 enum machine_mode, int, 278 enum reload_type, int); 279static rtx find_reloads_subreg_address (rtx, int, int, enum reload_type, 280 int, rtx); 281static void copy_replacements_1 (rtx *, rtx *, int); 282static int find_inc_amount (rtx, rtx); 283static int refers_to_mem_for_reload_p (rtx); 284static int refers_to_regno_for_reload_p (unsigned int, unsigned int, 285 rtx, rtx *); 286 287/* Add NEW to reg_equiv_alt_mem_list[REGNO] if it's not present in the 288 list yet. */ 289 290static void 291push_reg_equiv_alt_mem (int regno, rtx mem) 292{ 293 rtx it; 294 295 for (it = reg_equiv_alt_mem_list [regno]; it; it = XEXP (it, 1)) 296 if (rtx_equal_p (XEXP (it, 0), mem)) 297 return; 298 299 reg_equiv_alt_mem_list [regno] 300 = alloc_EXPR_LIST (REG_EQUIV, mem, 301 reg_equiv_alt_mem_list [regno]); 302} 303 304/* Determine if any secondary reloads are needed for loading (if IN_P is 305 nonzero) or storing (if IN_P is zero) X to or from a reload register of 306 register class RELOAD_CLASS in mode RELOAD_MODE. If secondary reloads 307 are needed, push them. 308 309 Return the reload number of the secondary reload we made, or -1 if 310 we didn't need one. *PICODE is set to the insn_code to use if we do 311 need a secondary reload. */ 312 313static int 314push_secondary_reload (int in_p, rtx x, int opnum, int optional, 315 enum reg_class reload_class, 316 enum machine_mode reload_mode, enum reload_type type, 317 enum insn_code *picode, secondary_reload_info *prev_sri) 318{ 319 enum reg_class class = NO_REGS; 320 enum reg_class scratch_class; 321 enum machine_mode mode = reload_mode; 322 enum insn_code icode = CODE_FOR_nothing; 323 enum insn_code t_icode = CODE_FOR_nothing; 324 enum reload_type secondary_type; 325 int s_reload, t_reload = -1; 326 const char *scratch_constraint; 327 char letter; 328 secondary_reload_info sri; 329 330 if (type == RELOAD_FOR_INPUT_ADDRESS 331 || type == RELOAD_FOR_OUTPUT_ADDRESS 332 || type == RELOAD_FOR_INPADDR_ADDRESS 333 || type == RELOAD_FOR_OUTADDR_ADDRESS) 334 secondary_type = type; 335 else 336 secondary_type = in_p ? RELOAD_FOR_INPUT_ADDRESS : RELOAD_FOR_OUTPUT_ADDRESS; 337 338 *picode = CODE_FOR_nothing; 339 340 /* If X is a paradoxical SUBREG, use the inner value to determine both the 341 mode and object being reloaded. */ 342 if (GET_CODE (x) == SUBREG 343 && (GET_MODE_SIZE (GET_MODE (x)) 344 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))) 345 { 346 x = SUBREG_REG (x); 347 reload_mode = GET_MODE (x); 348 } 349 350 /* If X is a pseudo-register that has an equivalent MEM (actually, if it 351 is still a pseudo-register by now, it *must* have an equivalent MEM 352 but we don't want to assume that), use that equivalent when seeing if 353 a secondary reload is needed since whether or not a reload is needed 354 might be sensitive to the form of the MEM. */ 355 356 if (REG_P (x) && REGNO (x) >= FIRST_PSEUDO_REGISTER 357 && reg_equiv_mem[REGNO (x)] != 0) 358 x = reg_equiv_mem[REGNO (x)]; 359 360 sri.icode = CODE_FOR_nothing; 361 sri.prev_sri = prev_sri; 362 class = targetm.secondary_reload (in_p, x, reload_class, reload_mode, &sri); 363 icode = sri.icode; 364 365 /* If we don't need any secondary registers, done. */ 366 if (class == NO_REGS && icode == CODE_FOR_nothing) 367 return -1; 368 369 if (class != NO_REGS) 370 t_reload = push_secondary_reload (in_p, x, opnum, optional, class, 371 reload_mode, type, &t_icode, &sri); 372 373 /* If we will be using an insn, the secondary reload is for a 374 scratch register. */ 375 376 if (icode != CODE_FOR_nothing) 377 { 378 /* If IN_P is nonzero, the reload register will be the output in 379 operand 0. If IN_P is zero, the reload register will be the input 380 in operand 1. Outputs should have an initial "=", which we must 381 skip. */ 382 383 /* ??? It would be useful to be able to handle only two, or more than 384 three, operands, but for now we can only handle the case of having 385 exactly three: output, input and one temp/scratch. */ 386 gcc_assert (insn_data[(int) icode].n_operands == 3); 387 388 /* ??? We currently have no way to represent a reload that needs 389 an icode to reload from an intermediate tertiary reload register. 390 We should probably have a new field in struct reload to tag a 391 chain of scratch operand reloads onto. */ 392 gcc_assert (class == NO_REGS); 393 394 scratch_constraint = insn_data[(int) icode].operand[2].constraint; 395 gcc_assert (*scratch_constraint == '='); 396 scratch_constraint++; 397 if (*scratch_constraint == '&') 398 scratch_constraint++; 399 letter = *scratch_constraint; 400 scratch_class = (letter == 'r' ? GENERAL_REGS 401 : REG_CLASS_FROM_CONSTRAINT ((unsigned char) letter, 402 scratch_constraint)); 403 404 class = scratch_class; 405 mode = insn_data[(int) icode].operand[2].mode; 406 } 407 408 /* This case isn't valid, so fail. Reload is allowed to use the same 409 register for RELOAD_FOR_INPUT_ADDRESS and RELOAD_FOR_INPUT reloads, but 410 in the case of a secondary register, we actually need two different 411 registers for correct code. We fail here to prevent the possibility of 412 silently generating incorrect code later. 413 414 The convention is that secondary input reloads are valid only if the 415 secondary_class is different from class. If you have such a case, you 416 can not use secondary reloads, you must work around the problem some 417 other way. 418 419 Allow this when a reload_in/out pattern is being used. I.e. assume 420 that the generated code handles this case. */ 421 422 gcc_assert (!in_p || class != reload_class || icode != CODE_FOR_nothing 423 || t_icode != CODE_FOR_nothing); 424 425 /* See if we can reuse an existing secondary reload. */ 426 for (s_reload = 0; s_reload < n_reloads; s_reload++) 427 if (rld[s_reload].secondary_p 428 && (reg_class_subset_p (class, rld[s_reload].class) 429 || reg_class_subset_p (rld[s_reload].class, class)) 430 && ((in_p && rld[s_reload].inmode == mode) 431 || (! in_p && rld[s_reload].outmode == mode)) 432 && ((in_p && rld[s_reload].secondary_in_reload == t_reload) 433 || (! in_p && rld[s_reload].secondary_out_reload == t_reload)) 434 && ((in_p && rld[s_reload].secondary_in_icode == t_icode) 435 || (! in_p && rld[s_reload].secondary_out_icode == t_icode)) 436 && (SMALL_REGISTER_CLASS_P (class) || SMALL_REGISTER_CLASSES) 437 && MERGABLE_RELOADS (secondary_type, rld[s_reload].when_needed, 438 opnum, rld[s_reload].opnum)) 439 { 440 if (in_p) 441 rld[s_reload].inmode = mode; 442 if (! in_p) 443 rld[s_reload].outmode = mode; 444 445 if (reg_class_subset_p (class, rld[s_reload].class)) 446 rld[s_reload].class = class; 447 448 rld[s_reload].opnum = MIN (rld[s_reload].opnum, opnum); 449 rld[s_reload].optional &= optional; 450 rld[s_reload].secondary_p = 1; 451 if (MERGE_TO_OTHER (secondary_type, rld[s_reload].when_needed, 452 opnum, rld[s_reload].opnum)) 453 rld[s_reload].when_needed = RELOAD_OTHER; 454 } 455 456 if (s_reload == n_reloads) 457 { 458#ifdef SECONDARY_MEMORY_NEEDED 459 /* If we need a memory location to copy between the two reload regs, 460 set it up now. Note that we do the input case before making 461 the reload and the output case after. This is due to the 462 way reloads are output. */ 463 464 if (in_p && icode == CODE_FOR_nothing 465 && SECONDARY_MEMORY_NEEDED (class, reload_class, mode)) 466 { 467 get_secondary_mem (x, reload_mode, opnum, type); 468 469 /* We may have just added new reloads. Make sure we add 470 the new reload at the end. */ 471 s_reload = n_reloads; 472 } 473#endif 474 475 /* We need to make a new secondary reload for this register class. */ 476 rld[s_reload].in = rld[s_reload].out = 0; 477 rld[s_reload].class = class; 478 479 rld[s_reload].inmode = in_p ? mode : VOIDmode; 480 rld[s_reload].outmode = ! in_p ? mode : VOIDmode; 481 rld[s_reload].reg_rtx = 0; 482 rld[s_reload].optional = optional; 483 rld[s_reload].inc = 0; 484 /* Maybe we could combine these, but it seems too tricky. */ 485 rld[s_reload].nocombine = 1; 486 rld[s_reload].in_reg = 0; 487 rld[s_reload].out_reg = 0; 488 rld[s_reload].opnum = opnum; 489 rld[s_reload].when_needed = secondary_type; 490 rld[s_reload].secondary_in_reload = in_p ? t_reload : -1; 491 rld[s_reload].secondary_out_reload = ! in_p ? t_reload : -1; 492 rld[s_reload].secondary_in_icode = in_p ? t_icode : CODE_FOR_nothing; 493 rld[s_reload].secondary_out_icode 494 = ! in_p ? t_icode : CODE_FOR_nothing; 495 rld[s_reload].secondary_p = 1; 496 497 n_reloads++; 498 499#ifdef SECONDARY_MEMORY_NEEDED 500 if (! in_p && icode == CODE_FOR_nothing 501 && SECONDARY_MEMORY_NEEDED (reload_class, class, mode)) 502 get_secondary_mem (x, mode, opnum, type); 503#endif 504 } 505 506 *picode = icode; 507 return s_reload; 508} 509 510/* If a secondary reload is needed, return its class. If both an intermediate 511 register and a scratch register is needed, we return the class of the 512 intermediate register. */ 513enum reg_class 514secondary_reload_class (bool in_p, enum reg_class class, 515 enum machine_mode mode, rtx x) 516{ 517 enum insn_code icode; 518 secondary_reload_info sri; 519 520 sri.icode = CODE_FOR_nothing; 521 sri.prev_sri = NULL; 522 class = targetm.secondary_reload (in_p, x, class, mode, &sri); 523 icode = sri.icode; 524 525 /* If there are no secondary reloads at all, we return NO_REGS. 526 If an intermediate register is needed, we return its class. */ 527 if (icode == CODE_FOR_nothing || class != NO_REGS) 528 return class; 529 530 /* No intermediate register is needed, but we have a special reload 531 pattern, which we assume for now needs a scratch register. */ 532 return scratch_reload_class (icode); 533} 534 535/* ICODE is the insn_code of a reload pattern. Check that it has exactly 536 three operands, verify that operand 2 is an output operand, and return 537 its register class. 538 ??? We'd like to be able to handle any pattern with at least 2 operands, 539 for zero or more scratch registers, but that needs more infrastructure. */ 540enum reg_class 541scratch_reload_class (enum insn_code icode) 542{ 543 const char *scratch_constraint; 544 char scratch_letter; 545 enum reg_class class; 546 547 gcc_assert (insn_data[(int) icode].n_operands == 3); 548 scratch_constraint = insn_data[(int) icode].operand[2].constraint; 549 gcc_assert (*scratch_constraint == '='); 550 scratch_constraint++; 551 if (*scratch_constraint == '&') 552 scratch_constraint++; 553 scratch_letter = *scratch_constraint; 554 if (scratch_letter == 'r') 555 return GENERAL_REGS; 556 class = REG_CLASS_FROM_CONSTRAINT ((unsigned char) scratch_letter, 557 scratch_constraint); 558 gcc_assert (class != NO_REGS); 559 return class; 560} 561 562#ifdef SECONDARY_MEMORY_NEEDED 563 564/* Return a memory location that will be used to copy X in mode MODE. 565 If we haven't already made a location for this mode in this insn, 566 call find_reloads_address on the location being returned. */ 567 568rtx 569get_secondary_mem (rtx x ATTRIBUTE_UNUSED, enum machine_mode mode, 570 int opnum, enum reload_type type) 571{ 572 rtx loc; 573 int mem_valid; 574 575 /* By default, if MODE is narrower than a word, widen it to a word. 576 This is required because most machines that require these memory 577 locations do not support short load and stores from all registers 578 (e.g., FP registers). */ 579 580#ifdef SECONDARY_MEMORY_NEEDED_MODE 581 mode = SECONDARY_MEMORY_NEEDED_MODE (mode); 582#else 583 if (GET_MODE_BITSIZE (mode) < BITS_PER_WORD && INTEGRAL_MODE_P (mode)) 584 mode = mode_for_size (BITS_PER_WORD, GET_MODE_CLASS (mode), 0); 585#endif 586 587 /* If we already have made a MEM for this operand in MODE, return it. */ 588 if (secondary_memlocs_elim[(int) mode][opnum] != 0) 589 return secondary_memlocs_elim[(int) mode][opnum]; 590 591 /* If this is the first time we've tried to get a MEM for this mode, 592 allocate a new one. `something_changed' in reload will get set 593 by noticing that the frame size has changed. */ 594 595 if (secondary_memlocs[(int) mode] == 0) 596 { 597#ifdef SECONDARY_MEMORY_NEEDED_RTX 598 secondary_memlocs[(int) mode] = SECONDARY_MEMORY_NEEDED_RTX (mode); 599#else 600 secondary_memlocs[(int) mode] 601 = assign_stack_local (mode, GET_MODE_SIZE (mode), 0); 602#endif 603 } 604 605 /* Get a version of the address doing any eliminations needed. If that 606 didn't give us a new MEM, make a new one if it isn't valid. */ 607 608 loc = eliminate_regs (secondary_memlocs[(int) mode], VOIDmode, NULL_RTX); 609 mem_valid = strict_memory_address_p (mode, XEXP (loc, 0)); 610 611 if (! mem_valid && loc == secondary_memlocs[(int) mode]) 612 loc = copy_rtx (loc); 613 614 /* The only time the call below will do anything is if the stack 615 offset is too large. In that case IND_LEVELS doesn't matter, so we 616 can just pass a zero. Adjust the type to be the address of the 617 corresponding object. If the address was valid, save the eliminated 618 address. If it wasn't valid, we need to make a reload each time, so 619 don't save it. */ 620 621 if (! mem_valid) 622 { 623 type = (type == RELOAD_FOR_INPUT ? RELOAD_FOR_INPUT_ADDRESS 624 : type == RELOAD_FOR_OUTPUT ? RELOAD_FOR_OUTPUT_ADDRESS 625 : RELOAD_OTHER); 626 627 find_reloads_address (mode, &loc, XEXP (loc, 0), &XEXP (loc, 0), 628 opnum, type, 0, 0); 629 } 630 631 secondary_memlocs_elim[(int) mode][opnum] = loc; 632 if (secondary_memlocs_elim_used <= (int)mode) 633 secondary_memlocs_elim_used = (int)mode + 1; 634 return loc; 635} 636 637/* Clear any secondary memory locations we've made. */ 638 639void 640clear_secondary_mem (void) 641{ 642 memset (secondary_memlocs, 0, sizeof secondary_memlocs); 643} 644#endif /* SECONDARY_MEMORY_NEEDED */ 645 646 647/* Find the largest class which has at least one register valid in 648 mode INNER, and which for every such register, that register number 649 plus N is also valid in OUTER (if in range) and is cheap to move 650 into REGNO. Such a class must exist. */ 651 652static enum reg_class 653find_valid_class (enum machine_mode outer ATTRIBUTE_UNUSED, 654 enum machine_mode inner ATTRIBUTE_UNUSED, int n, 655 unsigned int dest_regno ATTRIBUTE_UNUSED) 656{ 657 int best_cost = -1; 658 int class; 659 int regno; 660 enum reg_class best_class = NO_REGS; 661 enum reg_class dest_class ATTRIBUTE_UNUSED = REGNO_REG_CLASS (dest_regno); 662 unsigned int best_size = 0; 663 int cost; 664 665 for (class = 1; class < N_REG_CLASSES; class++) 666 { 667 int bad = 0; 668 int good = 0; 669 for (regno = 0; regno < FIRST_PSEUDO_REGISTER - n && ! bad; regno++) 670 if (TEST_HARD_REG_BIT (reg_class_contents[class], regno)) 671 { 672 if (HARD_REGNO_MODE_OK (regno, inner)) 673 { 674 good = 1; 675 if (! TEST_HARD_REG_BIT (reg_class_contents[class], regno + n) 676 || ! HARD_REGNO_MODE_OK (regno + n, outer)) 677 bad = 1; 678 } 679 } 680 681 if (bad || !good) 682 continue; 683 cost = REGISTER_MOVE_COST (outer, class, dest_class); 684 685 if ((reg_class_size[class] > best_size 686 && (best_cost < 0 || best_cost >= cost)) 687 || best_cost > cost) 688 { 689 best_class = class; 690 best_size = reg_class_size[class]; 691 best_cost = REGISTER_MOVE_COST (outer, class, dest_class); 692 } 693 } 694 695 gcc_assert (best_size != 0); 696 697 return best_class; 698} 699 700/* Return the number of a previously made reload that can be combined with 701 a new one, or n_reloads if none of the existing reloads can be used. 702 OUT, CLASS, TYPE and OPNUM are the same arguments as passed to 703 push_reload, they determine the kind of the new reload that we try to 704 combine. P_IN points to the corresponding value of IN, which can be 705 modified by this function. 706 DONT_SHARE is nonzero if we can't share any input-only reload for IN. */ 707 708static int 709find_reusable_reload (rtx *p_in, rtx out, enum reg_class class, 710 enum reload_type type, int opnum, int dont_share) 711{ 712 rtx in = *p_in; 713 int i; 714 /* We can't merge two reloads if the output of either one is 715 earlyclobbered. */ 716 717 if (earlyclobber_operand_p (out)) 718 return n_reloads; 719 720 /* We can use an existing reload if the class is right 721 and at least one of IN and OUT is a match 722 and the other is at worst neutral. 723 (A zero compared against anything is neutral.) 724 725 If SMALL_REGISTER_CLASSES, don't use existing reloads unless they are 726 for the same thing since that can cause us to need more reload registers 727 than we otherwise would. */ 728 729 for (i = 0; i < n_reloads; i++) 730 if ((reg_class_subset_p (class, rld[i].class) 731 || reg_class_subset_p (rld[i].class, class)) 732 /* If the existing reload has a register, it must fit our class. */ 733 && (rld[i].reg_rtx == 0 734 || TEST_HARD_REG_BIT (reg_class_contents[(int) class], 735 true_regnum (rld[i].reg_rtx))) 736 && ((in != 0 && MATCHES (rld[i].in, in) && ! dont_share 737 && (out == 0 || rld[i].out == 0 || MATCHES (rld[i].out, out))) 738 || (out != 0 && MATCHES (rld[i].out, out) 739 && (in == 0 || rld[i].in == 0 || MATCHES (rld[i].in, in)))) 740 && (rld[i].out == 0 || ! earlyclobber_operand_p (rld[i].out)) 741 && (SMALL_REGISTER_CLASS_P (class) || SMALL_REGISTER_CLASSES) 742 && MERGABLE_RELOADS (type, rld[i].when_needed, opnum, rld[i].opnum)) 743 return i; 744 745 /* Reloading a plain reg for input can match a reload to postincrement 746 that reg, since the postincrement's value is the right value. 747 Likewise, it can match a preincrement reload, since we regard 748 the preincrementation as happening before any ref in this insn 749 to that register. */ 750 for (i = 0; i < n_reloads; i++) 751 if ((reg_class_subset_p (class, rld[i].class) 752 || reg_class_subset_p (rld[i].class, class)) 753 /* If the existing reload has a register, it must fit our 754 class. */ 755 && (rld[i].reg_rtx == 0 756 || TEST_HARD_REG_BIT (reg_class_contents[(int) class], 757 true_regnum (rld[i].reg_rtx))) 758 && out == 0 && rld[i].out == 0 && rld[i].in != 0 759 && ((REG_P (in) 760 && GET_RTX_CLASS (GET_CODE (rld[i].in)) == RTX_AUTOINC 761 && MATCHES (XEXP (rld[i].in, 0), in)) 762 || (REG_P (rld[i].in) 763 && GET_RTX_CLASS (GET_CODE (in)) == RTX_AUTOINC 764 && MATCHES (XEXP (in, 0), rld[i].in))) 765 && (rld[i].out == 0 || ! earlyclobber_operand_p (rld[i].out)) 766 && (SMALL_REGISTER_CLASS_P (class) || SMALL_REGISTER_CLASSES) 767 && MERGABLE_RELOADS (type, rld[i].when_needed, 768 opnum, rld[i].opnum)) 769 { 770 /* Make sure reload_in ultimately has the increment, 771 not the plain register. */ 772 if (REG_P (in)) 773 *p_in = rld[i].in; 774 return i; 775 } 776 return n_reloads; 777} 778 779/* Return nonzero if X is a SUBREG which will require reloading of its 780 SUBREG_REG expression. */ 781 782static int 783reload_inner_reg_of_subreg (rtx x, enum machine_mode mode, int output) 784{ 785 rtx inner; 786 787 /* Only SUBREGs are problematical. */ 788 if (GET_CODE (x) != SUBREG) 789 return 0; 790 791 inner = SUBREG_REG (x); 792 793 /* If INNER is a constant or PLUS, then INNER must be reloaded. */ 794 if (CONSTANT_P (inner) || GET_CODE (inner) == PLUS) 795 return 1; 796 797 /* If INNER is not a hard register, then INNER will not need to 798 be reloaded. */ 799 if (!REG_P (inner) 800 || REGNO (inner) >= FIRST_PSEUDO_REGISTER) 801 return 0; 802 803 /* If INNER is not ok for MODE, then INNER will need reloading. */ 804 if (! HARD_REGNO_MODE_OK (subreg_regno (x), mode)) 805 return 1; 806 807 /* If the outer part is a word or smaller, INNER larger than a 808 word and the number of regs for INNER is not the same as the 809 number of words in INNER, then INNER will need reloading. */ 810 return (GET_MODE_SIZE (mode) <= UNITS_PER_WORD 811 && output 812 && GET_MODE_SIZE (GET_MODE (inner)) > UNITS_PER_WORD 813 && ((GET_MODE_SIZE (GET_MODE (inner)) / UNITS_PER_WORD) 814 != (int) hard_regno_nregs[REGNO (inner)][GET_MODE (inner)])); 815} 816 817/* Return nonzero if IN can be reloaded into REGNO with mode MODE without 818 requiring an extra reload register. The caller has already found that 819 IN contains some reference to REGNO, so check that we can produce the 820 new value in a single step. E.g. if we have 821 (set (reg r13) (plus (reg r13) (const int 1))), and there is an 822 instruction that adds one to a register, this should succeed. 823 However, if we have something like 824 (set (reg r13) (plus (reg r13) (const int 999))), and the constant 999 825 needs to be loaded into a register first, we need a separate reload 826 register. 827 Such PLUS reloads are generated by find_reload_address_part. 828 The out-of-range PLUS expressions are usually introduced in the instruction 829 patterns by register elimination and substituting pseudos without a home 830 by their function-invariant equivalences. */ 831static int 832can_reload_into (rtx in, int regno, enum machine_mode mode) 833{ 834 rtx dst, test_insn; 835 int r = 0; 836 struct recog_data save_recog_data; 837 838 /* For matching constraints, we often get notional input reloads where 839 we want to use the original register as the reload register. I.e. 840 technically this is a non-optional input-output reload, but IN is 841 already a valid register, and has been chosen as the reload register. 842 Speed this up, since it trivially works. */ 843 if (REG_P (in)) 844 return 1; 845 846 /* To test MEMs properly, we'd have to take into account all the reloads 847 that are already scheduled, which can become quite complicated. 848 And since we've already handled address reloads for this MEM, it 849 should always succeed anyway. */ 850 if (MEM_P (in)) 851 return 1; 852 853 /* If we can make a simple SET insn that does the job, everything should 854 be fine. */ 855 dst = gen_rtx_REG (mode, regno); 856 test_insn = make_insn_raw (gen_rtx_SET (VOIDmode, dst, in)); 857 save_recog_data = recog_data; 858 if (recog_memoized (test_insn) >= 0) 859 { 860 extract_insn (test_insn); 861 r = constrain_operands (1); 862 } 863 recog_data = save_recog_data; 864 return r; 865} 866 867/* Record one reload that needs to be performed. 868 IN is an rtx saying where the data are to be found before this instruction. 869 OUT says where they must be stored after the instruction. 870 (IN is zero for data not read, and OUT is zero for data not written.) 871 INLOC and OUTLOC point to the places in the instructions where 872 IN and OUT were found. 873 If IN and OUT are both nonzero, it means the same register must be used 874 to reload both IN and OUT. 875 876 CLASS is a register class required for the reloaded data. 877 INMODE is the machine mode that the instruction requires 878 for the reg that replaces IN and OUTMODE is likewise for OUT. 879 880 If IN is zero, then OUT's location and mode should be passed as 881 INLOC and INMODE. 882 883 STRICT_LOW is the 1 if there is a containing STRICT_LOW_PART rtx. 884 885 OPTIONAL nonzero means this reload does not need to be performed: 886 it can be discarded if that is more convenient. 887 888 OPNUM and TYPE say what the purpose of this reload is. 889 890 The return value is the reload-number for this reload. 891 892 If both IN and OUT are nonzero, in some rare cases we might 893 want to make two separate reloads. (Actually we never do this now.) 894 Therefore, the reload-number for OUT is stored in 895 output_reloadnum when we return; the return value applies to IN. 896 Usually (presently always), when IN and OUT are nonzero, 897 the two reload-numbers are equal, but the caller should be careful to 898 distinguish them. */ 899 900int 901push_reload (rtx in, rtx out, rtx *inloc, rtx *outloc, 902 enum reg_class class, enum machine_mode inmode, 903 enum machine_mode outmode, int strict_low, int optional, 904 int opnum, enum reload_type type) 905{ 906 int i; 907 int dont_share = 0; 908 int dont_remove_subreg = 0; 909 rtx *in_subreg_loc = 0, *out_subreg_loc = 0; 910 int secondary_in_reload = -1, secondary_out_reload = -1; 911 enum insn_code secondary_in_icode = CODE_FOR_nothing; 912 enum insn_code secondary_out_icode = CODE_FOR_nothing; 913 914 /* INMODE and/or OUTMODE could be VOIDmode if no mode 915 has been specified for the operand. In that case, 916 use the operand's mode as the mode to reload. */ 917 if (inmode == VOIDmode && in != 0) 918 inmode = GET_MODE (in); 919 if (outmode == VOIDmode && out != 0) 920 outmode = GET_MODE (out); 921 922 /* If IN is a pseudo register everywhere-equivalent to a constant, and 923 it is not in a hard register, reload straight from the constant, 924 since we want to get rid of such pseudo registers. 925 Often this is done earlier, but not always in find_reloads_address. */ 926 if (in != 0 && REG_P (in)) 927 { 928 int regno = REGNO (in); 929 930 if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 931 && reg_equiv_constant[regno] != 0) 932 in = reg_equiv_constant[regno]; 933 } 934 935 /* Likewise for OUT. Of course, OUT will never be equivalent to 936 an actual constant, but it might be equivalent to a memory location 937 (in the case of a parameter). */ 938 if (out != 0 && REG_P (out)) 939 { 940 int regno = REGNO (out); 941 942 if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0 943 && reg_equiv_constant[regno] != 0) 944 out = reg_equiv_constant[regno]; 945 } 946 947 /* If we have a read-write operand with an address side-effect, 948 change either IN or OUT so the side-effect happens only once. */ 949 if (in != 0 && out != 0 && MEM_P (in) && rtx_equal_p (in, out)) 950 switch (GET_CODE (XEXP (in, 0))) 951 { 952 case POST_INC: case POST_DEC: case POST_MODIFY: 953 in = replace_equiv_address_nv (in, XEXP (XEXP (in, 0), 0)); 954 break; 955 956 case PRE_INC: case PRE_DEC: case PRE_MODIFY: 957 out = replace_equiv_address_nv (out, XEXP (XEXP (out, 0), 0)); 958 break; 959 960 default: 961 break; 962 } 963 964 /* If we are reloading a (SUBREG constant ...), really reload just the 965 inside expression in its own mode. Similarly for (SUBREG (PLUS ...)). 966 If we have (SUBREG:M1 (MEM:M2 ...) ...) (or an inner REG that is still 967 a pseudo and hence will become a MEM) with M1 wider than M2 and the 968 register is a pseudo, also reload the inside expression. 969 For machines that extend byte loads, do this for any SUBREG of a pseudo 970 where both M1 and M2 are a word or smaller, M1 is wider than M2, and 971 M2 is an integral mode that gets extended when loaded. 972 Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where 973 either M1 is not valid for R or M2 is wider than a word but we only 974 need one word to store an M2-sized quantity in R. 975 (However, if OUT is nonzero, we need to reload the reg *and* 976 the subreg, so do nothing here, and let following statement handle it.) 977 978 Note that the case of (SUBREG (CONST_INT...)...) is handled elsewhere; 979 we can't handle it here because CONST_INT does not indicate a mode. 980 981 Similarly, we must reload the inside expression if we have a 982 STRICT_LOW_PART (presumably, in == out in the cas). 983 984 Also reload the inner expression if it does not require a secondary 985 reload but the SUBREG does. 986 987 Finally, reload the inner expression if it is a register that is in 988 the class whose registers cannot be referenced in a different size 989 and M1 is not the same size as M2. If subreg_lowpart_p is false, we 990 cannot reload just the inside since we might end up with the wrong 991 register class. But if it is inside a STRICT_LOW_PART, we have 992 no choice, so we hope we do get the right register class there. */ 993 994 if (in != 0 && GET_CODE (in) == SUBREG 995 && (subreg_lowpart_p (in) || strict_low) 996#ifdef CANNOT_CHANGE_MODE_CLASS 997 && !CANNOT_CHANGE_MODE_CLASS (GET_MODE (SUBREG_REG (in)), inmode, class) 998#endif 999 && (CONSTANT_P (SUBREG_REG (in)) 1000 || GET_CODE (SUBREG_REG (in)) == PLUS 1001 || strict_low 1002 || (((REG_P (SUBREG_REG (in)) 1003 && REGNO (SUBREG_REG (in)) >= FIRST_PSEUDO_REGISTER) 1004 || MEM_P (SUBREG_REG (in))) 1005 && ((GET_MODE_SIZE (inmode) 1006 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))) 1007#ifdef LOAD_EXTEND_OP 1008 || (GET_MODE_SIZE (inmode) <= UNITS_PER_WORD 1009 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) 1010 <= UNITS_PER_WORD) 1011 && (GET_MODE_SIZE (inmode) 1012 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))) 1013 && INTEGRAL_MODE_P (GET_MODE (SUBREG_REG (in))) 1014 && LOAD_EXTEND_OP (GET_MODE (SUBREG_REG (in))) != UNKNOWN) 1015#endif 1016#ifdef WORD_REGISTER_OPERATIONS 1017 || ((GET_MODE_SIZE (inmode) 1018 < GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))) 1019 && ((GET_MODE_SIZE (inmode) - 1) / UNITS_PER_WORD == 1020 ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) - 1) 1021 / UNITS_PER_WORD))) 1022#endif 1023 )) 1024 || (REG_P (SUBREG_REG (in)) 1025 && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER 1026 /* The case where out is nonzero 1027 is handled differently in the following statement. */ 1028 && (out == 0 || subreg_lowpart_p (in)) 1029 && ((GET_MODE_SIZE (inmode) <= UNITS_PER_WORD 1030 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) 1031 > UNITS_PER_WORD) 1032 && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) 1033 / UNITS_PER_WORD) 1034 != (int) hard_regno_nregs[REGNO (SUBREG_REG (in))] 1035 [GET_MODE (SUBREG_REG (in))])) 1036 || ! HARD_REGNO_MODE_OK (subreg_regno (in), inmode))) 1037 || (secondary_reload_class (1, class, inmode, in) != NO_REGS 1038 && (secondary_reload_class (1, class, GET_MODE (SUBREG_REG (in)), 1039 SUBREG_REG (in)) 1040 == NO_REGS)) 1041#ifdef CANNOT_CHANGE_MODE_CLASS 1042 || (REG_P (SUBREG_REG (in)) 1043 && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER 1044 && REG_CANNOT_CHANGE_MODE_P 1045 (REGNO (SUBREG_REG (in)), GET_MODE (SUBREG_REG (in)), inmode)) 1046#endif 1047 )) 1048 { 1049 in_subreg_loc = inloc; 1050 inloc = &SUBREG_REG (in); 1051 in = *inloc; 1052#if ! defined (LOAD_EXTEND_OP) && ! defined (WORD_REGISTER_OPERATIONS) 1053 if (MEM_P (in)) 1054 /* This is supposed to happen only for paradoxical subregs made by 1055 combine.c. (SUBREG (MEM)) isn't supposed to occur other ways. */ 1056 gcc_assert (GET_MODE_SIZE (GET_MODE (in)) <= GET_MODE_SIZE (inmode)); 1057#endif 1058 inmode = GET_MODE (in); 1059 } 1060 1061 /* Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where 1062 either M1 is not valid for R or M2 is wider than a word but we only 1063 need one word to store an M2-sized quantity in R. 1064 1065 However, we must reload the inner reg *as well as* the subreg in 1066 that case. */ 1067 1068 /* Similar issue for (SUBREG constant ...) if it was not handled by the 1069 code above. This can happen if SUBREG_BYTE != 0. */ 1070 1071 if (in != 0 && reload_inner_reg_of_subreg (in, inmode, 0)) 1072 { 1073 enum reg_class in_class = class; 1074 1075 if (REG_P (SUBREG_REG (in))) 1076 in_class 1077 = find_valid_class (inmode, GET_MODE (SUBREG_REG (in)), 1078 subreg_regno_offset (REGNO (SUBREG_REG (in)), 1079 GET_MODE (SUBREG_REG (in)), 1080 SUBREG_BYTE (in), 1081 GET_MODE (in)), 1082 REGNO (SUBREG_REG (in))); 1083 1084 /* This relies on the fact that emit_reload_insns outputs the 1085 instructions for input reloads of type RELOAD_OTHER in the same 1086 order as the reloads. Thus if the outer reload is also of type 1087 RELOAD_OTHER, we are guaranteed that this inner reload will be 1088 output before the outer reload. */ 1089 push_reload (SUBREG_REG (in), NULL_RTX, &SUBREG_REG (in), (rtx *) 0, 1090 in_class, VOIDmode, VOIDmode, 0, 0, opnum, type); 1091 dont_remove_subreg = 1; 1092 } 1093 1094 /* Similarly for paradoxical and problematical SUBREGs on the output. 1095 Note that there is no reason we need worry about the previous value 1096 of SUBREG_REG (out); even if wider than out, 1097 storing in a subreg is entitled to clobber it all 1098 (except in the case of STRICT_LOW_PART, 1099 and in that case the constraint should label it input-output.) */ 1100 if (out != 0 && GET_CODE (out) == SUBREG 1101 && (subreg_lowpart_p (out) || strict_low) 1102#ifdef CANNOT_CHANGE_MODE_CLASS 1103 && !CANNOT_CHANGE_MODE_CLASS (GET_MODE (SUBREG_REG (out)), outmode, class) 1104#endif 1105 && (CONSTANT_P (SUBREG_REG (out)) 1106 || strict_low 1107 || (((REG_P (SUBREG_REG (out)) 1108 && REGNO (SUBREG_REG (out)) >= FIRST_PSEUDO_REGISTER) 1109 || MEM_P (SUBREG_REG (out))) 1110 && ((GET_MODE_SIZE (outmode) 1111 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (out)))) 1112#ifdef WORD_REGISTER_OPERATIONS 1113 || ((GET_MODE_SIZE (outmode) 1114 < GET_MODE_SIZE (GET_MODE (SUBREG_REG (out)))) 1115 && ((GET_MODE_SIZE (outmode) - 1) / UNITS_PER_WORD == 1116 ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (out))) - 1) 1117 / UNITS_PER_WORD))) 1118#endif 1119 )) 1120 || (REG_P (SUBREG_REG (out)) 1121 && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER 1122 && ((GET_MODE_SIZE (outmode) <= UNITS_PER_WORD 1123 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (out))) 1124 > UNITS_PER_WORD) 1125 && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (out))) 1126 / UNITS_PER_WORD) 1127 != (int) hard_regno_nregs[REGNO (SUBREG_REG (out))] 1128 [GET_MODE (SUBREG_REG (out))])) 1129 || ! HARD_REGNO_MODE_OK (subreg_regno (out), outmode))) 1130 || (secondary_reload_class (0, class, outmode, out) != NO_REGS 1131 && (secondary_reload_class (0, class, GET_MODE (SUBREG_REG (out)), 1132 SUBREG_REG (out)) 1133 == NO_REGS)) 1134#ifdef CANNOT_CHANGE_MODE_CLASS 1135 || (REG_P (SUBREG_REG (out)) 1136 && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER 1137 && REG_CANNOT_CHANGE_MODE_P (REGNO (SUBREG_REG (out)), 1138 GET_MODE (SUBREG_REG (out)), 1139 outmode)) 1140#endif 1141 )) 1142 { 1143 out_subreg_loc = outloc; 1144 outloc = &SUBREG_REG (out); 1145 out = *outloc; 1146#if ! defined (LOAD_EXTEND_OP) && ! defined (WORD_REGISTER_OPERATIONS) 1147 gcc_assert (!MEM_P (out) 1148 || GET_MODE_SIZE (GET_MODE (out)) 1149 <= GET_MODE_SIZE (outmode)); 1150#endif 1151 outmode = GET_MODE (out); 1152 } 1153 1154 /* Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where 1155 either M1 is not valid for R or M2 is wider than a word but we only 1156 need one word to store an M2-sized quantity in R. 1157 1158 However, we must reload the inner reg *as well as* the subreg in 1159 that case. In this case, the inner reg is an in-out reload. */ 1160 1161 if (out != 0 && reload_inner_reg_of_subreg (out, outmode, 1)) 1162 { 1163 /* This relies on the fact that emit_reload_insns outputs the 1164 instructions for output reloads of type RELOAD_OTHER in reverse 1165 order of the reloads. Thus if the outer reload is also of type 1166 RELOAD_OTHER, we are guaranteed that this inner reload will be 1167 output after the outer reload. */ 1168 dont_remove_subreg = 1; 1169 push_reload (SUBREG_REG (out), SUBREG_REG (out), &SUBREG_REG (out), 1170 &SUBREG_REG (out), 1171 find_valid_class (outmode, GET_MODE (SUBREG_REG (out)), 1172 subreg_regno_offset (REGNO (SUBREG_REG (out)), 1173 GET_MODE (SUBREG_REG (out)), 1174 SUBREG_BYTE (out), 1175 GET_MODE (out)), 1176 REGNO (SUBREG_REG (out))), 1177 VOIDmode, VOIDmode, 0, 0, 1178 opnum, RELOAD_OTHER); 1179 } 1180 1181 /* If IN appears in OUT, we can't share any input-only reload for IN. */ 1182 if (in != 0 && out != 0 && MEM_P (out) 1183 && (REG_P (in) || MEM_P (in) || GET_CODE (in) == PLUS) 1184 && reg_overlap_mentioned_for_reload_p (in, XEXP (out, 0))) 1185 dont_share = 1; 1186 1187 /* If IN is a SUBREG of a hard register, make a new REG. This 1188 simplifies some of the cases below. */ 1189 1190 if (in != 0 && GET_CODE (in) == SUBREG && REG_P (SUBREG_REG (in)) 1191 && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER 1192 && ! dont_remove_subreg) 1193 in = gen_rtx_REG (GET_MODE (in), subreg_regno (in)); 1194 1195 /* Similarly for OUT. */ 1196 if (out != 0 && GET_CODE (out) == SUBREG 1197 && REG_P (SUBREG_REG (out)) 1198 && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER 1199 && ! dont_remove_subreg) 1200 out = gen_rtx_REG (GET_MODE (out), subreg_regno (out)); 1201 1202 /* Narrow down the class of register wanted if that is 1203 desirable on this machine for efficiency. */ 1204 { 1205 enum reg_class preferred_class = class; 1206 1207 if (in != 0) 1208 preferred_class = PREFERRED_RELOAD_CLASS (in, class); 1209 1210 /* Output reloads may need analogous treatment, different in detail. */ 1211#ifdef PREFERRED_OUTPUT_RELOAD_CLASS 1212 if (out != 0) 1213 preferred_class = PREFERRED_OUTPUT_RELOAD_CLASS (out, preferred_class); 1214#endif 1215 1216 /* Discard what the target said if we cannot do it. */ 1217 if (preferred_class != NO_REGS 1218 || (optional && type == RELOAD_FOR_OUTPUT)) 1219 class = preferred_class; 1220 } 1221 1222 /* Make sure we use a class that can handle the actual pseudo 1223 inside any subreg. For example, on the 386, QImode regs 1224 can appear within SImode subregs. Although GENERAL_REGS 1225 can handle SImode, QImode needs a smaller class. */ 1226#ifdef LIMIT_RELOAD_CLASS 1227 if (in_subreg_loc) 1228 class = LIMIT_RELOAD_CLASS (inmode, class); 1229 else if (in != 0 && GET_CODE (in) == SUBREG) 1230 class = LIMIT_RELOAD_CLASS (GET_MODE (SUBREG_REG (in)), class); 1231 1232 if (out_subreg_loc) 1233 class = LIMIT_RELOAD_CLASS (outmode, class); 1234 if (out != 0 && GET_CODE (out) == SUBREG) 1235 class = LIMIT_RELOAD_CLASS (GET_MODE (SUBREG_REG (out)), class); 1236#endif 1237 1238 /* Verify that this class is at least possible for the mode that 1239 is specified. */ 1240 if (this_insn_is_asm) 1241 { 1242 enum machine_mode mode; 1243 if (GET_MODE_SIZE (inmode) > GET_MODE_SIZE (outmode)) 1244 mode = inmode; 1245 else 1246 mode = outmode; 1247 if (mode == VOIDmode) 1248 { 1249 error_for_asm (this_insn, "cannot reload integer constant " 1250 "operand in %<asm%>"); 1251 mode = word_mode; 1252 if (in != 0) 1253 inmode = word_mode; 1254 if (out != 0) 1255 outmode = word_mode; 1256 } 1257 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) 1258 if (HARD_REGNO_MODE_OK (i, mode) 1259 && TEST_HARD_REG_BIT (reg_class_contents[(int) class], i)) 1260 { 1261 int nregs = hard_regno_nregs[i][mode]; 1262 1263 int j; 1264 for (j = 1; j < nregs; j++) 1265 if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], i + j)) 1266 break; 1267 if (j == nregs) 1268 break; 1269 } 1270 if (i == FIRST_PSEUDO_REGISTER) 1271 { 1272 error_for_asm (this_insn, "impossible register constraint " 1273 "in %<asm%>"); 1274 /* Avoid further trouble with this insn. */ 1275 PATTERN (this_insn) = gen_rtx_USE (VOIDmode, const0_rtx); 1276 /* We used to continue here setting class to ALL_REGS, but it triggers 1277 sanity check on i386 for: 1278 void foo(long double d) 1279 { 1280 asm("" :: "a" (d)); 1281 } 1282 Returning zero here ought to be safe as we take care in 1283 find_reloads to not process the reloads when instruction was 1284 replaced by USE. */ 1285 1286 return 0; 1287 } 1288 } 1289 1290 /* Optional output reloads are always OK even if we have no register class, 1291 since the function of these reloads is only to have spill_reg_store etc. 1292 set, so that the storing insn can be deleted later. */ 1293 gcc_assert (class != NO_REGS 1294 || (optional != 0 && type == RELOAD_FOR_OUTPUT)); 1295 1296 i = find_reusable_reload (&in, out, class, type, opnum, dont_share); 1297 1298 if (i == n_reloads) 1299 { 1300 /* See if we need a secondary reload register to move between CLASS 1301 and IN or CLASS and OUT. Get the icode and push any required reloads 1302 needed for each of them if so. */ 1303 1304 if (in != 0) 1305 secondary_in_reload 1306 = push_secondary_reload (1, in, opnum, optional, class, inmode, type, 1307 &secondary_in_icode, NULL); 1308 if (out != 0 && GET_CODE (out) != SCRATCH) 1309 secondary_out_reload 1310 = push_secondary_reload (0, out, opnum, optional, class, outmode, 1311 type, &secondary_out_icode, NULL); 1312 1313 /* We found no existing reload suitable for re-use. 1314 So add an additional reload. */ 1315 1316#ifdef SECONDARY_MEMORY_NEEDED 1317 /* If a memory location is needed for the copy, make one. */ 1318 if (in != 0 1319 && (REG_P (in) 1320 || (GET_CODE (in) == SUBREG && REG_P (SUBREG_REG (in)))) 1321 && reg_or_subregno (in) < FIRST_PSEUDO_REGISTER 1322 && SECONDARY_MEMORY_NEEDED (REGNO_REG_CLASS (reg_or_subregno (in)), 1323 class, inmode)) 1324 get_secondary_mem (in, inmode, opnum, type); 1325#endif 1326 1327 i = n_reloads; 1328 rld[i].in = in; 1329 rld[i].out = out; 1330 rld[i].class = class; 1331 rld[i].inmode = inmode; 1332 rld[i].outmode = outmode; 1333 rld[i].reg_rtx = 0; 1334 rld[i].optional = optional; 1335 rld[i].inc = 0; 1336 rld[i].nocombine = 0; 1337 rld[i].in_reg = inloc ? *inloc : 0; 1338 rld[i].out_reg = outloc ? *outloc : 0; 1339 rld[i].opnum = opnum; 1340 rld[i].when_needed = type; 1341 rld[i].secondary_in_reload = secondary_in_reload; 1342 rld[i].secondary_out_reload = secondary_out_reload; 1343 rld[i].secondary_in_icode = secondary_in_icode; 1344 rld[i].secondary_out_icode = secondary_out_icode; 1345 rld[i].secondary_p = 0; 1346 1347 n_reloads++; 1348 1349#ifdef SECONDARY_MEMORY_NEEDED 1350 if (out != 0 1351 && (REG_P (out) 1352 || (GET_CODE (out) == SUBREG && REG_P (SUBREG_REG (out)))) 1353 && reg_or_subregno (out) < FIRST_PSEUDO_REGISTER 1354 && SECONDARY_MEMORY_NEEDED (class, 1355 REGNO_REG_CLASS (reg_or_subregno (out)), 1356 outmode)) 1357 get_secondary_mem (out, outmode, opnum, type); 1358#endif 1359 } 1360 else 1361 { 1362 /* We are reusing an existing reload, 1363 but we may have additional information for it. 1364 For example, we may now have both IN and OUT 1365 while the old one may have just one of them. */ 1366 1367 /* The modes can be different. If they are, we want to reload in 1368 the larger mode, so that the value is valid for both modes. */ 1369 if (inmode != VOIDmode 1370 && GET_MODE_SIZE (inmode) > GET_MODE_SIZE (rld[i].inmode)) 1371 rld[i].inmode = inmode; 1372 if (outmode != VOIDmode 1373 && GET_MODE_SIZE (outmode) > GET_MODE_SIZE (rld[i].outmode)) 1374 rld[i].outmode = outmode; 1375 if (in != 0) 1376 { 1377 rtx in_reg = inloc ? *inloc : 0; 1378 /* If we merge reloads for two distinct rtl expressions that 1379 are identical in content, there might be duplicate address 1380 reloads. Remove the extra set now, so that if we later find 1381 that we can inherit this reload, we can get rid of the 1382 address reloads altogether. 1383 1384 Do not do this if both reloads are optional since the result 1385 would be an optional reload which could potentially leave 1386 unresolved address replacements. 1387 1388 It is not sufficient to call transfer_replacements since 1389 choose_reload_regs will remove the replacements for address 1390 reloads of inherited reloads which results in the same 1391 problem. */ 1392 if (rld[i].in != in && rtx_equal_p (in, rld[i].in) 1393 && ! (rld[i].optional && optional)) 1394 { 1395 /* We must keep the address reload with the lower operand 1396 number alive. */ 1397 if (opnum > rld[i].opnum) 1398 { 1399 remove_address_replacements (in); 1400 in = rld[i].in; 1401 in_reg = rld[i].in_reg; 1402 } 1403 else 1404 remove_address_replacements (rld[i].in); 1405 } 1406 rld[i].in = in; 1407 rld[i].in_reg = in_reg; 1408 } 1409 if (out != 0) 1410 { 1411 rld[i].out = out; 1412 rld[i].out_reg = outloc ? *outloc : 0; 1413 } 1414 if (reg_class_subset_p (class, rld[i].class)) 1415 rld[i].class = class; 1416 rld[i].optional &= optional; 1417 if (MERGE_TO_OTHER (type, rld[i].when_needed, 1418 opnum, rld[i].opnum)) 1419 rld[i].when_needed = RELOAD_OTHER; 1420 rld[i].opnum = MIN (rld[i].opnum, opnum); 1421 } 1422 1423 /* If the ostensible rtx being reloaded differs from the rtx found 1424 in the location to substitute, this reload is not safe to combine 1425 because we cannot reliably tell whether it appears in the insn. */ 1426 1427 if (in != 0 && in != *inloc) 1428 rld[i].nocombine = 1; 1429 1430#if 0 1431 /* This was replaced by changes in find_reloads_address_1 and the new 1432 function inc_for_reload, which go with a new meaning of reload_inc. */ 1433 1434 /* If this is an IN/OUT reload in an insn that sets the CC, 1435 it must be for an autoincrement. It doesn't work to store 1436 the incremented value after the insn because that would clobber the CC. 1437 So we must do the increment of the value reloaded from, 1438 increment it, store it back, then decrement again. */ 1439 if (out != 0 && sets_cc0_p (PATTERN (this_insn))) 1440 { 1441 out = 0; 1442 rld[i].out = 0; 1443 rld[i].inc = find_inc_amount (PATTERN (this_insn), in); 1444 /* If we did not find a nonzero amount-to-increment-by, 1445 that contradicts the belief that IN is being incremented 1446 in an address in this insn. */ 1447 gcc_assert (rld[i].inc != 0); 1448 } 1449#endif 1450 1451 /* If we will replace IN and OUT with the reload-reg, 1452 record where they are located so that substitution need 1453 not do a tree walk. */ 1454 1455 if (replace_reloads) 1456 { 1457 if (inloc != 0) 1458 { 1459 struct replacement *r = &replacements[n_replacements++]; 1460 r->what = i; 1461 r->subreg_loc = in_subreg_loc; 1462 r->where = inloc; 1463 r->mode = inmode; 1464 } 1465 if (outloc != 0 && outloc != inloc) 1466 { 1467 struct replacement *r = &replacements[n_replacements++]; 1468 r->what = i; 1469 r->where = outloc; 1470 r->subreg_loc = out_subreg_loc; 1471 r->mode = outmode; 1472 } 1473 } 1474 1475 /* If this reload is just being introduced and it has both 1476 an incoming quantity and an outgoing quantity that are 1477 supposed to be made to match, see if either one of the two 1478 can serve as the place to reload into. 1479 1480 If one of them is acceptable, set rld[i].reg_rtx 1481 to that one. */ 1482 1483 if (in != 0 && out != 0 && in != out && rld[i].reg_rtx == 0) 1484 { 1485 rld[i].reg_rtx = find_dummy_reload (in, out, inloc, outloc, 1486 inmode, outmode, 1487 rld[i].class, i, 1488 earlyclobber_operand_p (out)); 1489 1490 /* If the outgoing register already contains the same value 1491 as the incoming one, we can dispense with loading it. 1492 The easiest way to tell the caller that is to give a phony 1493 value for the incoming operand (same as outgoing one). */ 1494 if (rld[i].reg_rtx == out 1495 && (REG_P (in) || CONSTANT_P (in)) 1496 && 0 != find_equiv_reg (in, this_insn, 0, REGNO (out), 1497 static_reload_reg_p, i, inmode)) 1498 rld[i].in = out; 1499 } 1500 1501 /* If this is an input reload and the operand contains a register that 1502 dies in this insn and is used nowhere else, see if it is the right class 1503 to be used for this reload. Use it if so. (This occurs most commonly 1504 in the case of paradoxical SUBREGs and in-out reloads). We cannot do 1505 this if it is also an output reload that mentions the register unless 1506 the output is a SUBREG that clobbers an entire register. 1507 1508 Note that the operand might be one of the spill regs, if it is a 1509 pseudo reg and we are in a block where spilling has not taken place. 1510 But if there is no spilling in this block, that is OK. 1511 An explicitly used hard reg cannot be a spill reg. */ 1512 1513 if (rld[i].reg_rtx == 0 && in != 0 && hard_regs_live_known) 1514 { 1515 rtx note; 1516 int regno; 1517 enum machine_mode rel_mode = inmode; 1518 1519 if (out && GET_MODE_SIZE (outmode) > GET_MODE_SIZE (inmode)) 1520 rel_mode = outmode; 1521 1522 for (note = REG_NOTES (this_insn); note; note = XEXP (note, 1)) 1523 if (REG_NOTE_KIND (note) == REG_DEAD 1524 && REG_P (XEXP (note, 0)) 1525 && (regno = REGNO (XEXP (note, 0))) < FIRST_PSEUDO_REGISTER 1526 && reg_mentioned_p (XEXP (note, 0), in) 1527 /* Check that we don't use a hardreg for an uninitialized 1528 pseudo. See also find_dummy_reload(). */ 1529 && (ORIGINAL_REGNO (XEXP (note, 0)) < FIRST_PSEUDO_REGISTER 1530 || ! bitmap_bit_p (ENTRY_BLOCK_PTR->il.rtl->global_live_at_end, 1531 ORIGINAL_REGNO (XEXP (note, 0)))) 1532 && ! refers_to_regno_for_reload_p (regno, 1533 (regno 1534 + hard_regno_nregs[regno] 1535 [rel_mode]), 1536 PATTERN (this_insn), inloc) 1537 /* If this is also an output reload, IN cannot be used as 1538 the reload register if it is set in this insn unless IN 1539 is also OUT. */ 1540 && (out == 0 || in == out 1541 || ! hard_reg_set_here_p (regno, 1542 (regno 1543 + hard_regno_nregs[regno] 1544 [rel_mode]), 1545 PATTERN (this_insn))) 1546 /* ??? Why is this code so different from the previous? 1547 Is there any simple coherent way to describe the two together? 1548 What's going on here. */ 1549 && (in != out 1550 || (GET_CODE (in) == SUBREG 1551 && (((GET_MODE_SIZE (GET_MODE (in)) + (UNITS_PER_WORD - 1)) 1552 / UNITS_PER_WORD) 1553 == ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))) 1554 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)))) 1555 /* Make sure the operand fits in the reg that dies. */ 1556 && (GET_MODE_SIZE (rel_mode) 1557 <= GET_MODE_SIZE (GET_MODE (XEXP (note, 0)))) 1558 && HARD_REGNO_MODE_OK (regno, inmode) 1559 && HARD_REGNO_MODE_OK (regno, outmode)) 1560 { 1561 unsigned int offs; 1562 unsigned int nregs = MAX (hard_regno_nregs[regno][inmode], 1563 hard_regno_nregs[regno][outmode]); 1564 1565 for (offs = 0; offs < nregs; offs++) 1566 if (fixed_regs[regno + offs] 1567 || ! TEST_HARD_REG_BIT (reg_class_contents[(int) class], 1568 regno + offs)) 1569 break; 1570 1571 if (offs == nregs 1572 && (! (refers_to_regno_for_reload_p 1573 (regno, (regno + hard_regno_nregs[regno][inmode]), 1574 in, (rtx *)0)) 1575 || can_reload_into (in, regno, inmode))) 1576 { 1577 rld[i].reg_rtx = gen_rtx_REG (rel_mode, regno); 1578 break; 1579 } 1580 } 1581 } 1582 1583 if (out) 1584 output_reloadnum = i; 1585 1586 return i; 1587} 1588 1589/* Record an additional place we must replace a value 1590 for which we have already recorded a reload. 1591 RELOADNUM is the value returned by push_reload 1592 when the reload was recorded. 1593 This is used in insn patterns that use match_dup. */ 1594 1595static void 1596push_replacement (rtx *loc, int reloadnum, enum machine_mode mode) 1597{ 1598 if (replace_reloads) 1599 { 1600 struct replacement *r = &replacements[n_replacements++]; 1601 r->what = reloadnum; 1602 r->where = loc; 1603 r->subreg_loc = 0; 1604 r->mode = mode; 1605 } 1606} 1607 1608/* Duplicate any replacement we have recorded to apply at 1609 location ORIG_LOC to also be performed at DUP_LOC. 1610 This is used in insn patterns that use match_dup. */ 1611 1612static void 1613dup_replacements (rtx *dup_loc, rtx *orig_loc) 1614{ 1615 int i, n = n_replacements; 1616 1617 for (i = 0; i < n; i++) 1618 { 1619 struct replacement *r = &replacements[i]; 1620 if (r->where == orig_loc) 1621 push_replacement (dup_loc, r->what, r->mode); 1622 } 1623} 1624 1625/* Transfer all replacements that used to be in reload FROM to be in 1626 reload TO. */ 1627 1628void 1629transfer_replacements (int to, int from) 1630{ 1631 int i; 1632 1633 for (i = 0; i < n_replacements; i++) 1634 if (replacements[i].what == from) 1635 replacements[i].what = to; 1636} 1637 1638/* IN_RTX is the value loaded by a reload that we now decided to inherit, 1639 or a subpart of it. If we have any replacements registered for IN_RTX, 1640 cancel the reloads that were supposed to load them. 1641 Return nonzero if we canceled any reloads. */ 1642int 1643remove_address_replacements (rtx in_rtx) 1644{ 1645 int i, j; 1646 char reload_flags[MAX_RELOADS]; 1647 int something_changed = 0; 1648 1649 memset (reload_flags, 0, sizeof reload_flags); 1650 for (i = 0, j = 0; i < n_replacements; i++) 1651 { 1652 if (loc_mentioned_in_p (replacements[i].where, in_rtx)) 1653 reload_flags[replacements[i].what] |= 1; 1654 else 1655 { 1656 replacements[j++] = replacements[i]; 1657 reload_flags[replacements[i].what] |= 2; 1658 } 1659 } 1660 /* Note that the following store must be done before the recursive calls. */ 1661 n_replacements = j; 1662 1663 for (i = n_reloads - 1; i >= 0; i--) 1664 { 1665 if (reload_flags[i] == 1) 1666 { 1667 deallocate_reload_reg (i); 1668 remove_address_replacements (rld[i].in); 1669 rld[i].in = 0; 1670 something_changed = 1; 1671 } 1672 } 1673 return something_changed; 1674} 1675 1676/* If there is only one output reload, and it is not for an earlyclobber 1677 operand, try to combine it with a (logically unrelated) input reload 1678 to reduce the number of reload registers needed. 1679 1680 This is safe if the input reload does not appear in 1681 the value being output-reloaded, because this implies 1682 it is not needed any more once the original insn completes. 1683 1684 If that doesn't work, see we can use any of the registers that 1685 die in this insn as a reload register. We can if it is of the right 1686 class and does not appear in the value being output-reloaded. */ 1687 1688static void 1689combine_reloads (void) 1690{ 1691 int i; 1692 int output_reload = -1; 1693 int secondary_out = -1; 1694 rtx note; 1695 1696 /* Find the output reload; return unless there is exactly one 1697 and that one is mandatory. */ 1698 1699 for (i = 0; i < n_reloads; i++) 1700 if (rld[i].out != 0) 1701 { 1702 if (output_reload >= 0) 1703 return; 1704 output_reload = i; 1705 } 1706 1707 if (output_reload < 0 || rld[output_reload].optional) 1708 return; 1709 1710 /* An input-output reload isn't combinable. */ 1711 1712 if (rld[output_reload].in != 0) 1713 return; 1714 1715 /* If this reload is for an earlyclobber operand, we can't do anything. */ 1716 if (earlyclobber_operand_p (rld[output_reload].out)) 1717 return; 1718 1719 /* If there is a reload for part of the address of this operand, we would 1720 need to chnage it to RELOAD_FOR_OTHER_ADDRESS. But that would extend 1721 its life to the point where doing this combine would not lower the 1722 number of spill registers needed. */ 1723 for (i = 0; i < n_reloads; i++) 1724 if ((rld[i].when_needed == RELOAD_FOR_OUTPUT_ADDRESS 1725 || rld[i].when_needed == RELOAD_FOR_OUTADDR_ADDRESS) 1726 && rld[i].opnum == rld[output_reload].opnum) 1727 return; 1728 1729 /* Check each input reload; can we combine it? */ 1730 1731 for (i = 0; i < n_reloads; i++) 1732 if (rld[i].in && ! rld[i].optional && ! rld[i].nocombine 1733 /* Life span of this reload must not extend past main insn. */ 1734 && rld[i].when_needed != RELOAD_FOR_OUTPUT_ADDRESS 1735 && rld[i].when_needed != RELOAD_FOR_OUTADDR_ADDRESS 1736 && rld[i].when_needed != RELOAD_OTHER 1737 && (CLASS_MAX_NREGS (rld[i].class, rld[i].inmode) 1738 == CLASS_MAX_NREGS (rld[output_reload].class, 1739 rld[output_reload].outmode)) 1740 && rld[i].inc == 0 1741 && rld[i].reg_rtx == 0 1742#ifdef SECONDARY_MEMORY_NEEDED 1743 /* Don't combine two reloads with different secondary 1744 memory locations. */ 1745 && (secondary_memlocs_elim[(int) rld[output_reload].outmode][rld[i].opnum] == 0 1746 || secondary_memlocs_elim[(int) rld[output_reload].outmode][rld[output_reload].opnum] == 0 1747 || rtx_equal_p (secondary_memlocs_elim[(int) rld[output_reload].outmode][rld[i].opnum], 1748 secondary_memlocs_elim[(int) rld[output_reload].outmode][rld[output_reload].opnum])) 1749#endif 1750 && (SMALL_REGISTER_CLASSES 1751 ? (rld[i].class == rld[output_reload].class) 1752 : (reg_class_subset_p (rld[i].class, 1753 rld[output_reload].class) 1754 || reg_class_subset_p (rld[output_reload].class, 1755 rld[i].class))) 1756 && (MATCHES (rld[i].in, rld[output_reload].out) 1757 /* Args reversed because the first arg seems to be 1758 the one that we imagine being modified 1759 while the second is the one that might be affected. */ 1760 || (! reg_overlap_mentioned_for_reload_p (rld[output_reload].out, 1761 rld[i].in) 1762 /* However, if the input is a register that appears inside 1763 the output, then we also can't share. 1764 Imagine (set (mem (reg 69)) (plus (reg 69) ...)). 1765 If the same reload reg is used for both reg 69 and the 1766 result to be stored in memory, then that result 1767 will clobber the address of the memory ref. */ 1768 && ! (REG_P (rld[i].in) 1769 && reg_overlap_mentioned_for_reload_p (rld[i].in, 1770 rld[output_reload].out)))) 1771 && ! reload_inner_reg_of_subreg (rld[i].in, rld[i].inmode, 1772 rld[i].when_needed != RELOAD_FOR_INPUT) 1773 && (reg_class_size[(int) rld[i].class] 1774 || SMALL_REGISTER_CLASSES) 1775 /* We will allow making things slightly worse by combining an 1776 input and an output, but no worse than that. */ 1777 && (rld[i].when_needed == RELOAD_FOR_INPUT 1778 || rld[i].when_needed == RELOAD_FOR_OUTPUT)) 1779 { 1780 int j; 1781 1782 /* We have found a reload to combine with! */ 1783 rld[i].out = rld[output_reload].out; 1784 rld[i].out_reg = rld[output_reload].out_reg; 1785 rld[i].outmode = rld[output_reload].outmode; 1786 /* Mark the old output reload as inoperative. */ 1787 rld[output_reload].out = 0; 1788 /* The combined reload is needed for the entire insn. */ 1789 rld[i].when_needed = RELOAD_OTHER; 1790 /* If the output reload had a secondary reload, copy it. */ 1791 if (rld[output_reload].secondary_out_reload != -1) 1792 { 1793 rld[i].secondary_out_reload 1794 = rld[output_reload].secondary_out_reload; 1795 rld[i].secondary_out_icode 1796 = rld[output_reload].secondary_out_icode; 1797 } 1798 1799#ifdef SECONDARY_MEMORY_NEEDED 1800 /* Copy any secondary MEM. */ 1801 if (secondary_memlocs_elim[(int) rld[output_reload].outmode][rld[output_reload].opnum] != 0) 1802 secondary_memlocs_elim[(int) rld[output_reload].outmode][rld[i].opnum] 1803 = secondary_memlocs_elim[(int) rld[output_reload].outmode][rld[output_reload].opnum]; 1804#endif 1805 /* If required, minimize the register class. */ 1806 if (reg_class_subset_p (rld[output_reload].class, 1807 rld[i].class)) 1808 rld[i].class = rld[output_reload].class; 1809 1810 /* Transfer all replacements from the old reload to the combined. */ 1811 for (j = 0; j < n_replacements; j++) 1812 if (replacements[j].what == output_reload) 1813 replacements[j].what = i; 1814 1815 return; 1816 } 1817 1818 /* If this insn has only one operand that is modified or written (assumed 1819 to be the first), it must be the one corresponding to this reload. It 1820 is safe to use anything that dies in this insn for that output provided 1821 that it does not occur in the output (we already know it isn't an 1822 earlyclobber. If this is an asm insn, give up. */ 1823 1824 if (INSN_CODE (this_insn) == -1) 1825 return; 1826 1827 for (i = 1; i < insn_data[INSN_CODE (this_insn)].n_operands; i++) 1828 if (insn_data[INSN_CODE (this_insn)].operand[i].constraint[0] == '=' 1829 || insn_data[INSN_CODE (this_insn)].operand[i].constraint[0] == '+') 1830 return; 1831 1832 /* See if some hard register that dies in this insn and is not used in 1833 the output is the right class. Only works if the register we pick 1834 up can fully hold our output reload. */ 1835 for (note = REG_NOTES (this_insn); note; note = XEXP (note, 1)) 1836 if (REG_NOTE_KIND (note) == REG_DEAD 1837 && REG_P (XEXP (note, 0)) 1838 && ! reg_overlap_mentioned_for_reload_p (XEXP (note, 0), 1839 rld[output_reload].out) 1840 && REGNO (XEXP (note, 0)) < FIRST_PSEUDO_REGISTER 1841 && HARD_REGNO_MODE_OK (REGNO (XEXP (note, 0)), rld[output_reload].outmode) 1842 && TEST_HARD_REG_BIT (reg_class_contents[(int) rld[output_reload].class], 1843 REGNO (XEXP (note, 0))) 1844 && (hard_regno_nregs[REGNO (XEXP (note, 0))][rld[output_reload].outmode] 1845 <= hard_regno_nregs[REGNO (XEXP (note, 0))][GET_MODE (XEXP (note, 0))]) 1846 /* Ensure that a secondary or tertiary reload for this output 1847 won't want this register. */ 1848 && ((secondary_out = rld[output_reload].secondary_out_reload) == -1 1849 || (! (TEST_HARD_REG_BIT 1850 (reg_class_contents[(int) rld[secondary_out].class], 1851 REGNO (XEXP (note, 0)))) 1852 && ((secondary_out = rld[secondary_out].secondary_out_reload) == -1 1853 || ! (TEST_HARD_REG_BIT 1854 (reg_class_contents[(int) rld[secondary_out].class], 1855 REGNO (XEXP (note, 0))))))) 1856 && ! fixed_regs[REGNO (XEXP (note, 0))] 1857 /* Check that we don't use a hardreg for an uninitialized 1858 pseudo. See also find_dummy_reload(). */ 1859 && (ORIGINAL_REGNO (XEXP (note, 0)) < FIRST_PSEUDO_REGISTER 1860 || ! bitmap_bit_p (ENTRY_BLOCK_PTR->il.rtl->global_live_at_end, 1861 ORIGINAL_REGNO (XEXP (note, 0))))) 1862 { 1863 rld[output_reload].reg_rtx 1864 = gen_rtx_REG (rld[output_reload].outmode, 1865 REGNO (XEXP (note, 0))); 1866 return; 1867 } 1868} 1869 1870/* Try to find a reload register for an in-out reload (expressions IN and OUT). 1871 See if one of IN and OUT is a register that may be used; 1872 this is desirable since a spill-register won't be needed. 1873 If so, return the register rtx that proves acceptable. 1874 1875 INLOC and OUTLOC are locations where IN and OUT appear in the insn. 1876 CLASS is the register class required for the reload. 1877 1878 If FOR_REAL is >= 0, it is the number of the reload, 1879 and in some cases when it can be discovered that OUT doesn't need 1880 to be computed, clear out rld[FOR_REAL].out. 1881 1882 If FOR_REAL is -1, this should not be done, because this call 1883 is just to see if a register can be found, not to find and install it. 1884 1885 EARLYCLOBBER is nonzero if OUT is an earlyclobber operand. This 1886 puts an additional constraint on being able to use IN for OUT since 1887 IN must not appear elsewhere in the insn (it is assumed that IN itself 1888 is safe from the earlyclobber). */ 1889 1890static rtx 1891find_dummy_reload (rtx real_in, rtx real_out, rtx *inloc, rtx *outloc, 1892 enum machine_mode inmode, enum machine_mode outmode, 1893 enum reg_class class, int for_real, int earlyclobber) 1894{ 1895 rtx in = real_in; 1896 rtx out = real_out; 1897 int in_offset = 0; 1898 int out_offset = 0; 1899 rtx value = 0; 1900 1901 /* If operands exceed a word, we can't use either of them 1902 unless they have the same size. */ 1903 if (GET_MODE_SIZE (outmode) != GET_MODE_SIZE (inmode) 1904 && (GET_MODE_SIZE (outmode) > UNITS_PER_WORD 1905 || GET_MODE_SIZE (inmode) > UNITS_PER_WORD)) 1906 return 0; 1907 1908 /* Note that {in,out}_offset are needed only when 'in' or 'out' 1909 respectively refers to a hard register. */ 1910 1911 /* Find the inside of any subregs. */ 1912 while (GET_CODE (out) == SUBREG) 1913 { 1914 if (REG_P (SUBREG_REG (out)) 1915 && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER) 1916 out_offset += subreg_regno_offset (REGNO (SUBREG_REG (out)), 1917 GET_MODE (SUBREG_REG (out)), 1918 SUBREG_BYTE (out), 1919 GET_MODE (out)); 1920 out = SUBREG_REG (out); 1921 } 1922 while (GET_CODE (in) == SUBREG) 1923 { 1924 if (REG_P (SUBREG_REG (in)) 1925 && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER) 1926 in_offset += subreg_regno_offset (REGNO (SUBREG_REG (in)), 1927 GET_MODE (SUBREG_REG (in)), 1928 SUBREG_BYTE (in), 1929 GET_MODE (in)); 1930 in = SUBREG_REG (in); 1931 } 1932 1933 /* Narrow down the reg class, the same way push_reload will; 1934 otherwise we might find a dummy now, but push_reload won't. */ 1935 { 1936 enum reg_class preferred_class = PREFERRED_RELOAD_CLASS (in, class); 1937 if (preferred_class != NO_REGS) 1938 class = preferred_class; 1939 } 1940 1941 /* See if OUT will do. */ 1942 if (REG_P (out) 1943 && REGNO (out) < FIRST_PSEUDO_REGISTER) 1944 { 1945 unsigned int regno = REGNO (out) + out_offset; 1946 unsigned int nwords = hard_regno_nregs[regno][outmode]; 1947 rtx saved_rtx; 1948 1949 /* When we consider whether the insn uses OUT, 1950 ignore references within IN. They don't prevent us 1951 from copying IN into OUT, because those refs would 1952 move into the insn that reloads IN. 1953 1954 However, we only ignore IN in its role as this reload. 1955 If the insn uses IN elsewhere and it contains OUT, 1956 that counts. We can't be sure it's the "same" operand 1957 so it might not go through this reload. */ 1958 saved_rtx = *inloc; 1959 *inloc = const0_rtx; 1960 1961 if (regno < FIRST_PSEUDO_REGISTER 1962 && HARD_REGNO_MODE_OK (regno, outmode) 1963 && ! refers_to_regno_for_reload_p (regno, regno + nwords, 1964 PATTERN (this_insn), outloc)) 1965 { 1966 unsigned int i; 1967 1968 for (i = 0; i < nwords; i++) 1969 if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], 1970 regno + i)) 1971 break; 1972 1973 if (i == nwords) 1974 { 1975 if (REG_P (real_out)) 1976 value = real_out; 1977 else 1978 value = gen_rtx_REG (outmode, regno); 1979 } 1980 } 1981 1982 *inloc = saved_rtx; 1983 } 1984 1985 /* Consider using IN if OUT was not acceptable 1986 or if OUT dies in this insn (like the quotient in a divmod insn). 1987 We can't use IN unless it is dies in this insn, 1988 which means we must know accurately which hard regs are live. 1989 Also, the result can't go in IN if IN is used within OUT, 1990 or if OUT is an earlyclobber and IN appears elsewhere in the insn. */ 1991 if (hard_regs_live_known 1992 && REG_P (in) 1993 && REGNO (in) < FIRST_PSEUDO_REGISTER 1994 && (value == 0 1995 || find_reg_note (this_insn, REG_UNUSED, real_out)) 1996 && find_reg_note (this_insn, REG_DEAD, real_in) 1997 && !fixed_regs[REGNO (in)] 1998 && HARD_REGNO_MODE_OK (REGNO (in), 1999 /* The only case where out and real_out might 2000 have different modes is where real_out 2001 is a subreg, and in that case, out 2002 has a real mode. */ 2003 (GET_MODE (out) != VOIDmode 2004 ? GET_MODE (out) : outmode)) 2005 /* But only do all this if we can be sure, that this input 2006 operand doesn't correspond with an uninitialized pseudoreg. 2007 global can assign some hardreg to it, which is the same as 2008 a different pseudo also currently live (as it can ignore the 2009 conflict). So we never must introduce writes to such hardregs, 2010 as they would clobber the other live pseudo using the same. 2011 See also PR20973. */ 2012 && (ORIGINAL_REGNO (in) < FIRST_PSEUDO_REGISTER 2013 || ! bitmap_bit_p (ENTRY_BLOCK_PTR->il.rtl->global_live_at_end, 2014 ORIGINAL_REGNO (in)))) 2015 { 2016 unsigned int regno = REGNO (in) + in_offset; 2017 unsigned int nwords = hard_regno_nregs[regno][inmode]; 2018 2019 if (! refers_to_regno_for_reload_p (regno, regno + nwords, out, (rtx*) 0) 2020 && ! hard_reg_set_here_p (regno, regno + nwords, 2021 PATTERN (this_insn)) 2022 && (! earlyclobber 2023 || ! refers_to_regno_for_reload_p (regno, regno + nwords, 2024 PATTERN (this_insn), inloc))) 2025 { 2026 unsigned int i; 2027 2028 for (i = 0; i < nwords; i++) 2029 if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], 2030 regno + i)) 2031 break; 2032 2033 if (i == nwords) 2034 { 2035 /* If we were going to use OUT as the reload reg 2036 and changed our mind, it means OUT is a dummy that 2037 dies here. So don't bother copying value to it. */ 2038 if (for_real >= 0 && value == real_out) 2039 rld[for_real].out = 0; 2040 if (REG_P (real_in)) 2041 value = real_in; 2042 else 2043 value = gen_rtx_REG (inmode, regno); 2044 } 2045 } 2046 } 2047 2048 return value; 2049} 2050 2051/* This page contains subroutines used mainly for determining 2052 whether the IN or an OUT of a reload can serve as the 2053 reload register. */ 2054 2055/* Return 1 if X is an operand of an insn that is being earlyclobbered. */ 2056 2057int 2058earlyclobber_operand_p (rtx x) 2059{ 2060 int i; 2061 2062 for (i = 0; i < n_earlyclobbers; i++) 2063 if (reload_earlyclobbers[i] == x) 2064 return 1; 2065 2066 return 0; 2067} 2068 2069/* Return 1 if expression X alters a hard reg in the range 2070 from BEG_REGNO (inclusive) to END_REGNO (exclusive), 2071 either explicitly or in the guise of a pseudo-reg allocated to REGNO. 2072 X should be the body of an instruction. */ 2073 2074static int 2075hard_reg_set_here_p (unsigned int beg_regno, unsigned int end_regno, rtx x) 2076{ 2077 if (GET_CODE (x) == SET || GET_CODE (x) == CLOBBER) 2078 { 2079 rtx op0 = SET_DEST (x); 2080 2081 while (GET_CODE (op0) == SUBREG) 2082 op0 = SUBREG_REG (op0); 2083 if (REG_P (op0)) 2084 { 2085 unsigned int r = REGNO (op0); 2086 2087 /* See if this reg overlaps range under consideration. */ 2088 if (r < end_regno 2089 && r + hard_regno_nregs[r][GET_MODE (op0)] > beg_regno) 2090 return 1; 2091 } 2092 } 2093 else if (GET_CODE (x) == PARALLEL) 2094 { 2095 int i = XVECLEN (x, 0) - 1; 2096 2097 for (; i >= 0; i--) 2098 if (hard_reg_set_here_p (beg_regno, end_regno, XVECEXP (x, 0, i))) 2099 return 1; 2100 } 2101 2102 return 0; 2103} 2104 2105/* Return 1 if ADDR is a valid memory address for mode MODE, 2106 and check that each pseudo reg has the proper kind of 2107 hard reg. */ 2108 2109int 2110strict_memory_address_p (enum machine_mode mode ATTRIBUTE_UNUSED, rtx addr) 2111{ 2112 GO_IF_LEGITIMATE_ADDRESS (mode, addr, win); 2113 return 0; 2114 2115 win: 2116 return 1; 2117} 2118 2119/* Like rtx_equal_p except that it allows a REG and a SUBREG to match 2120 if they are the same hard reg, and has special hacks for 2121 autoincrement and autodecrement. 2122 This is specifically intended for find_reloads to use 2123 in determining whether two operands match. 2124 X is the operand whose number is the lower of the two. 2125 2126 The value is 2 if Y contains a pre-increment that matches 2127 a non-incrementing address in X. */ 2128 2129/* ??? To be completely correct, we should arrange to pass 2130 for X the output operand and for Y the input operand. 2131 For now, we assume that the output operand has the lower number 2132 because that is natural in (SET output (... input ...)). */ 2133 2134int 2135operands_match_p (rtx x, rtx y) 2136{ 2137 int i; 2138 RTX_CODE code = GET_CODE (x); 2139 const char *fmt; 2140 int success_2; 2141 2142 if (x == y) 2143 return 1; 2144 if ((code == REG || (code == SUBREG && REG_P (SUBREG_REG (x)))) 2145 && (REG_P (y) || (GET_CODE (y) == SUBREG 2146 && REG_P (SUBREG_REG (y))))) 2147 { 2148 int j; 2149 2150 if (code == SUBREG) 2151 { 2152 i = REGNO (SUBREG_REG (x)); 2153 if (i >= FIRST_PSEUDO_REGISTER) 2154 goto slow; 2155 i += subreg_regno_offset (REGNO (SUBREG_REG (x)), 2156 GET_MODE (SUBREG_REG (x)), 2157 SUBREG_BYTE (x), 2158 GET_MODE (x)); 2159 } 2160 else 2161 i = REGNO (x); 2162 2163 if (GET_CODE (y) == SUBREG) 2164 { 2165 j = REGNO (SUBREG_REG (y)); 2166 if (j >= FIRST_PSEUDO_REGISTER) 2167 goto slow; 2168 j += subreg_regno_offset (REGNO (SUBREG_REG (y)), 2169 GET_MODE (SUBREG_REG (y)), 2170 SUBREG_BYTE (y), 2171 GET_MODE (y)); 2172 } 2173 else 2174 j = REGNO (y); 2175 2176 /* On a WORDS_BIG_ENDIAN machine, point to the last register of a 2177 multiple hard register group of scalar integer registers, so that 2178 for example (reg:DI 0) and (reg:SI 1) will be considered the same 2179 register. */ 2180 if (WORDS_BIG_ENDIAN && GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD 2181 && SCALAR_INT_MODE_P (GET_MODE (x)) 2182 && i < FIRST_PSEUDO_REGISTER) 2183 i += hard_regno_nregs[i][GET_MODE (x)] - 1; 2184 if (WORDS_BIG_ENDIAN && GET_MODE_SIZE (GET_MODE (y)) > UNITS_PER_WORD 2185 && SCALAR_INT_MODE_P (GET_MODE (y)) 2186 && j < FIRST_PSEUDO_REGISTER) 2187 j += hard_regno_nregs[j][GET_MODE (y)] - 1; 2188 2189 return i == j; 2190 } 2191 /* If two operands must match, because they are really a single 2192 operand of an assembler insn, then two postincrements are invalid 2193 because the assembler insn would increment only once. 2194 On the other hand, a postincrement matches ordinary indexing 2195 if the postincrement is the output operand. */ 2196 if (code == POST_DEC || code == POST_INC || code == POST_MODIFY) 2197 return operands_match_p (XEXP (x, 0), y); 2198 /* Two preincrements are invalid 2199 because the assembler insn would increment only once. 2200 On the other hand, a preincrement matches ordinary indexing 2201 if the preincrement is the input operand. 2202 In this case, return 2, since some callers need to do special 2203 things when this happens. */ 2204 if (GET_CODE (y) == PRE_DEC || GET_CODE (y) == PRE_INC 2205 || GET_CODE (y) == PRE_MODIFY) 2206 return operands_match_p (x, XEXP (y, 0)) ? 2 : 0; 2207 2208 slow: 2209 2210 /* Now we have disposed of all the cases in which different rtx codes 2211 can match. */ 2212 if (code != GET_CODE (y)) 2213 return 0; 2214 2215 /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */ 2216 if (GET_MODE (x) != GET_MODE (y)) 2217 return 0; 2218 2219 switch (code) 2220 { 2221 case CONST_INT: 2222 case CONST_DOUBLE: 2223 return 0; 2224 2225 case LABEL_REF: 2226 return XEXP (x, 0) == XEXP (y, 0); 2227 case SYMBOL_REF: 2228 return XSTR (x, 0) == XSTR (y, 0); 2229 2230 default: 2231 break; 2232 } 2233 2234 /* Compare the elements. If any pair of corresponding elements 2235 fail to match, return 0 for the whole things. */ 2236 2237 success_2 = 0; 2238 fmt = GET_RTX_FORMAT (code); 2239 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 2240 { 2241 int val, j; 2242 switch (fmt[i]) 2243 { 2244 case 'w': 2245 if (XWINT (x, i) != XWINT (y, i)) 2246 return 0; 2247 break; 2248 2249 case 'i': 2250 if (XINT (x, i) != XINT (y, i)) 2251 return 0; 2252 break; 2253 2254 case 'e': 2255 val = operands_match_p (XEXP (x, i), XEXP (y, i)); 2256 if (val == 0) 2257 return 0; 2258 /* If any subexpression returns 2, 2259 we should return 2 if we are successful. */ 2260 if (val == 2) 2261 success_2 = 1; 2262 break; 2263 2264 case '0': 2265 break; 2266 2267 case 'E': 2268 if (XVECLEN (x, i) != XVECLEN (y, i)) 2269 return 0; 2270 for (j = XVECLEN (x, i) - 1; j >= 0; --j) 2271 { 2272 val = operands_match_p (XVECEXP (x, i, j), XVECEXP (y, i, j)); 2273 if (val == 0) 2274 return 0; 2275 if (val == 2) 2276 success_2 = 1; 2277 } 2278 break; 2279 2280 /* It is believed that rtx's at this level will never 2281 contain anything but integers and other rtx's, 2282 except for within LABEL_REFs and SYMBOL_REFs. */ 2283 default: 2284 gcc_unreachable (); 2285 } 2286 } 2287 return 1 + success_2; 2288} 2289 2290/* Describe the range of registers or memory referenced by X. 2291 If X is a register, set REG_FLAG and put the first register 2292 number into START and the last plus one into END. 2293 If X is a memory reference, put a base address into BASE 2294 and a range of integer offsets into START and END. 2295 If X is pushing on the stack, we can assume it causes no trouble, 2296 so we set the SAFE field. */ 2297 2298static struct decomposition 2299decompose (rtx x) 2300{ 2301 struct decomposition val; 2302 int all_const = 0; 2303 2304 memset (&val, 0, sizeof (val)); 2305 2306 switch (GET_CODE (x)) 2307 { 2308 case MEM: 2309 { 2310 rtx base = NULL_RTX, offset = 0; 2311 rtx addr = XEXP (x, 0); 2312 2313 if (GET_CODE (addr) == PRE_DEC || GET_CODE (addr) == PRE_INC 2314 || GET_CODE (addr) == POST_DEC || GET_CODE (addr) == POST_INC) 2315 { 2316 val.base = XEXP (addr, 0); 2317 val.start = -GET_MODE_SIZE (GET_MODE (x)); 2318 val.end = GET_MODE_SIZE (GET_MODE (x)); 2319 val.safe = REGNO (val.base) == STACK_POINTER_REGNUM; 2320 return val; 2321 } 2322 2323 if (GET_CODE (addr) == PRE_MODIFY || GET_CODE (addr) == POST_MODIFY) 2324 { 2325 if (GET_CODE (XEXP (addr, 1)) == PLUS 2326 && XEXP (addr, 0) == XEXP (XEXP (addr, 1), 0) 2327 && CONSTANT_P (XEXP (XEXP (addr, 1), 1))) 2328 { 2329 val.base = XEXP (addr, 0); 2330 val.start = -INTVAL (XEXP (XEXP (addr, 1), 1)); 2331 val.end = INTVAL (XEXP (XEXP (addr, 1), 1)); 2332 val.safe = REGNO (val.base) == STACK_POINTER_REGNUM; 2333 return val; 2334 } 2335 } 2336 2337 if (GET_CODE (addr) == CONST) 2338 { 2339 addr = XEXP (addr, 0); 2340 all_const = 1; 2341 } 2342 if (GET_CODE (addr) == PLUS) 2343 { 2344 if (CONSTANT_P (XEXP (addr, 0))) 2345 { 2346 base = XEXP (addr, 1); 2347 offset = XEXP (addr, 0); 2348 } 2349 else if (CONSTANT_P (XEXP (addr, 1))) 2350 { 2351 base = XEXP (addr, 0); 2352 offset = XEXP (addr, 1); 2353 } 2354 } 2355 2356 if (offset == 0) 2357 { 2358 base = addr; 2359 offset = const0_rtx; 2360 } 2361 if (GET_CODE (offset) == CONST) 2362 offset = XEXP (offset, 0); 2363 if (GET_CODE (offset) == PLUS) 2364 { 2365 if (GET_CODE (XEXP (offset, 0)) == CONST_INT) 2366 { 2367 base = gen_rtx_PLUS (GET_MODE (base), base, XEXP (offset, 1)); 2368 offset = XEXP (offset, 0); 2369 } 2370 else if (GET_CODE (XEXP (offset, 1)) == CONST_INT) 2371 { 2372 base = gen_rtx_PLUS (GET_MODE (base), base, XEXP (offset, 0)); 2373 offset = XEXP (offset, 1); 2374 } 2375 else 2376 { 2377 base = gen_rtx_PLUS (GET_MODE (base), base, offset); 2378 offset = const0_rtx; 2379 } 2380 } 2381 else if (GET_CODE (offset) != CONST_INT) 2382 { 2383 base = gen_rtx_PLUS (GET_MODE (base), base, offset); 2384 offset = const0_rtx; 2385 } 2386 2387 if (all_const && GET_CODE (base) == PLUS) 2388 base = gen_rtx_CONST (GET_MODE (base), base); 2389 2390 gcc_assert (GET_CODE (offset) == CONST_INT); 2391 2392 val.start = INTVAL (offset); 2393 val.end = val.start + GET_MODE_SIZE (GET_MODE (x)); 2394 val.base = base; 2395 } 2396 break; 2397 2398 case REG: 2399 val.reg_flag = 1; 2400 val.start = true_regnum (x); 2401 if (val.start < 0 || val.start >= FIRST_PSEUDO_REGISTER) 2402 { 2403 /* A pseudo with no hard reg. */ 2404 val.start = REGNO (x); 2405 val.end = val.start + 1; 2406 } 2407 else 2408 /* A hard reg. */ 2409 val.end = val.start + hard_regno_nregs[val.start][GET_MODE (x)]; 2410 break; 2411 2412 case SUBREG: 2413 if (!REG_P (SUBREG_REG (x))) 2414 /* This could be more precise, but it's good enough. */ 2415 return decompose (SUBREG_REG (x)); 2416 val.reg_flag = 1; 2417 val.start = true_regnum (x); 2418 if (val.start < 0 || val.start >= FIRST_PSEUDO_REGISTER) 2419 return decompose (SUBREG_REG (x)); 2420 else 2421 /* A hard reg. */ 2422 val.end = val.start + hard_regno_nregs[val.start][GET_MODE (x)]; 2423 break; 2424 2425 case SCRATCH: 2426 /* This hasn't been assigned yet, so it can't conflict yet. */ 2427 val.safe = 1; 2428 break; 2429 2430 default: 2431 gcc_assert (CONSTANT_P (x)); 2432 val.safe = 1; 2433 break; 2434 } 2435 return val; 2436} 2437 2438/* Return 1 if altering Y will not modify the value of X. 2439 Y is also described by YDATA, which should be decompose (Y). */ 2440 2441static int 2442immune_p (rtx x, rtx y, struct decomposition ydata) 2443{ 2444 struct decomposition xdata; 2445 2446 if (ydata.reg_flag) 2447 return !refers_to_regno_for_reload_p (ydata.start, ydata.end, x, (rtx*) 0); 2448 if (ydata.safe) 2449 return 1; 2450 2451 gcc_assert (MEM_P (y)); 2452 /* If Y is memory and X is not, Y can't affect X. */ 2453 if (!MEM_P (x)) 2454 return 1; 2455 2456 xdata = decompose (x); 2457 2458 if (! rtx_equal_p (xdata.base, ydata.base)) 2459 { 2460 /* If bases are distinct symbolic constants, there is no overlap. */ 2461 if (CONSTANT_P (xdata.base) && CONSTANT_P (ydata.base)) 2462 return 1; 2463 /* Constants and stack slots never overlap. */ 2464 if (CONSTANT_P (xdata.base) 2465 && (ydata.base == frame_pointer_rtx 2466 || ydata.base == hard_frame_pointer_rtx 2467 || ydata.base == stack_pointer_rtx)) 2468 return 1; 2469 if (CONSTANT_P (ydata.base) 2470 && (xdata.base == frame_pointer_rtx 2471 || xdata.base == hard_frame_pointer_rtx 2472 || xdata.base == stack_pointer_rtx)) 2473 return 1; 2474 /* If either base is variable, we don't know anything. */ 2475 return 0; 2476 } 2477 2478 return (xdata.start >= ydata.end || ydata.start >= xdata.end); 2479} 2480 2481/* Similar, but calls decompose. */ 2482 2483int 2484safe_from_earlyclobber (rtx op, rtx clobber) 2485{ 2486 struct decomposition early_data; 2487 2488 early_data = decompose (clobber); 2489 return immune_p (op, clobber, early_data); 2490} 2491 2492/* Main entry point of this file: search the body of INSN 2493 for values that need reloading and record them with push_reload. 2494 REPLACE nonzero means record also where the values occur 2495 so that subst_reloads can be used. 2496 2497 IND_LEVELS says how many levels of indirection are supported by this 2498 machine; a value of zero means that a memory reference is not a valid 2499 memory address. 2500 2501 LIVE_KNOWN says we have valid information about which hard 2502 regs are live at each point in the program; this is true when 2503 we are called from global_alloc but false when stupid register 2504 allocation has been done. 2505 2506 RELOAD_REG_P if nonzero is a vector indexed by hard reg number 2507 which is nonnegative if the reg has been commandeered for reloading into. 2508 It is copied into STATIC_RELOAD_REG_P and referenced from there 2509 by various subroutines. 2510 2511 Return TRUE if some operands need to be changed, because of swapping 2512 commutative operands, reg_equiv_address substitution, or whatever. */ 2513 2514int 2515find_reloads (rtx insn, int replace, int ind_levels, int live_known, 2516 short *reload_reg_p) 2517{ 2518 int insn_code_number; 2519 int i, j; 2520 int noperands; 2521 /* These start out as the constraints for the insn 2522 and they are chewed up as we consider alternatives. */ 2523 char *constraints[MAX_RECOG_OPERANDS]; 2524 /* These are the preferred classes for an operand, or NO_REGS if it isn't 2525 a register. */ 2526 enum reg_class preferred_class[MAX_RECOG_OPERANDS]; 2527 char pref_or_nothing[MAX_RECOG_OPERANDS]; 2528 /* Nonzero for a MEM operand whose entire address needs a reload. 2529 May be -1 to indicate the entire address may or may not need a reload. */ 2530 int address_reloaded[MAX_RECOG_OPERANDS]; 2531 /* Nonzero for an address operand that needs to be completely reloaded. 2532 May be -1 to indicate the entire operand may or may not need a reload. */ 2533 int address_operand_reloaded[MAX_RECOG_OPERANDS]; 2534 /* Value of enum reload_type to use for operand. */ 2535 enum reload_type operand_type[MAX_RECOG_OPERANDS]; 2536 /* Value of enum reload_type to use within address of operand. */ 2537 enum reload_type address_type[MAX_RECOG_OPERANDS]; 2538 /* Save the usage of each operand. */ 2539 enum reload_usage { RELOAD_READ, RELOAD_READ_WRITE, RELOAD_WRITE } modified[MAX_RECOG_OPERANDS]; 2540 int no_input_reloads = 0, no_output_reloads = 0; 2541 int n_alternatives; 2542 int this_alternative[MAX_RECOG_OPERANDS]; 2543 char this_alternative_match_win[MAX_RECOG_OPERANDS]; 2544 char this_alternative_win[MAX_RECOG_OPERANDS]; 2545 char this_alternative_offmemok[MAX_RECOG_OPERANDS]; 2546 char this_alternative_earlyclobber[MAX_RECOG_OPERANDS]; 2547 int this_alternative_matches[MAX_RECOG_OPERANDS]; 2548 int swapped; 2549 int goal_alternative[MAX_RECOG_OPERANDS]; 2550 int this_alternative_number; 2551 int goal_alternative_number = 0; 2552 int operand_reloadnum[MAX_RECOG_OPERANDS]; 2553 int goal_alternative_matches[MAX_RECOG_OPERANDS]; 2554 int goal_alternative_matched[MAX_RECOG_OPERANDS]; 2555 char goal_alternative_match_win[MAX_RECOG_OPERANDS]; 2556 char goal_alternative_win[MAX_RECOG_OPERANDS]; 2557 char goal_alternative_offmemok[MAX_RECOG_OPERANDS]; 2558 char goal_alternative_earlyclobber[MAX_RECOG_OPERANDS]; 2559 int goal_alternative_swapped; 2560 int best; 2561 int commutative; 2562 char operands_match[MAX_RECOG_OPERANDS][MAX_RECOG_OPERANDS]; 2563 rtx substed_operand[MAX_RECOG_OPERANDS]; 2564 rtx body = PATTERN (insn); 2565 rtx set = single_set (insn); 2566 int goal_earlyclobber = 0, this_earlyclobber; 2567 enum machine_mode operand_mode[MAX_RECOG_OPERANDS]; 2568 int retval = 0; 2569 2570 this_insn = insn; 2571 n_reloads = 0; 2572 n_replacements = 0; 2573 n_earlyclobbers = 0; 2574 replace_reloads = replace; 2575 hard_regs_live_known = live_known; 2576 static_reload_reg_p = reload_reg_p; 2577 2578 /* JUMP_INSNs and CALL_INSNs are not allowed to have any output reloads; 2579 neither are insns that SET cc0. Insns that use CC0 are not allowed 2580 to have any input reloads. */ 2581 if (JUMP_P (insn) || CALL_P (insn)) 2582 no_output_reloads = 1; 2583 2584#ifdef HAVE_cc0 2585 if (reg_referenced_p (cc0_rtx, PATTERN (insn))) 2586 no_input_reloads = 1; 2587 if (reg_set_p (cc0_rtx, PATTERN (insn))) 2588 no_output_reloads = 1; 2589#endif 2590 2591#ifdef SECONDARY_MEMORY_NEEDED 2592 /* The eliminated forms of any secondary memory locations are per-insn, so 2593 clear them out here. */ 2594 2595 if (secondary_memlocs_elim_used) 2596 { 2597 memset (secondary_memlocs_elim, 0, 2598 sizeof (secondary_memlocs_elim[0]) * secondary_memlocs_elim_used); 2599 secondary_memlocs_elim_used = 0; 2600 } 2601#endif 2602 2603 /* Dispose quickly of (set (reg..) (reg..)) if both have hard regs and it 2604 is cheap to move between them. If it is not, there may not be an insn 2605 to do the copy, so we may need a reload. */ 2606 if (GET_CODE (body) == SET 2607 && REG_P (SET_DEST (body)) 2608 && REGNO (SET_DEST (body)) < FIRST_PSEUDO_REGISTER 2609 && REG_P (SET_SRC (body)) 2610 && REGNO (SET_SRC (body)) < FIRST_PSEUDO_REGISTER 2611 && REGISTER_MOVE_COST (GET_MODE (SET_SRC (body)), 2612 REGNO_REG_CLASS (REGNO (SET_SRC (body))), 2613 REGNO_REG_CLASS (REGNO (SET_DEST (body)))) == 2) 2614 return 0; 2615 2616 extract_insn (insn); 2617 2618 noperands = reload_n_operands = recog_data.n_operands; 2619 n_alternatives = recog_data.n_alternatives; 2620 2621 /* Just return "no reloads" if insn has no operands with constraints. */ 2622 if (noperands == 0 || n_alternatives == 0) 2623 return 0; 2624 2625 insn_code_number = INSN_CODE (insn); 2626 this_insn_is_asm = insn_code_number < 0; 2627 2628 memcpy (operand_mode, recog_data.operand_mode, 2629 noperands * sizeof (enum machine_mode)); 2630 memcpy (constraints, recog_data.constraints, noperands * sizeof (char *)); 2631 2632 commutative = -1; 2633 2634 /* If we will need to know, later, whether some pair of operands 2635 are the same, we must compare them now and save the result. 2636 Reloading the base and index registers will clobber them 2637 and afterward they will fail to match. */ 2638 2639 for (i = 0; i < noperands; i++) 2640 { 2641 char *p; 2642 int c; 2643 2644 substed_operand[i] = recog_data.operand[i]; 2645 p = constraints[i]; 2646 2647 modified[i] = RELOAD_READ; 2648 2649 /* Scan this operand's constraint to see if it is an output operand, 2650 an in-out operand, is commutative, or should match another. */ 2651 2652 while ((c = *p)) 2653 { 2654 p += CONSTRAINT_LEN (c, p); 2655 switch (c) 2656 { 2657 case '=': 2658 modified[i] = RELOAD_WRITE; 2659 break; 2660 case '+': 2661 modified[i] = RELOAD_READ_WRITE; 2662 break; 2663 case '%': 2664 { 2665 /* The last operand should not be marked commutative. */ 2666 gcc_assert (i != noperands - 1); 2667 2668 /* We currently only support one commutative pair of 2669 operands. Some existing asm code currently uses more 2670 than one pair. Previously, that would usually work, 2671 but sometimes it would crash the compiler. We 2672 continue supporting that case as well as we can by 2673 silently ignoring all but the first pair. In the 2674 future we may handle it correctly. */ 2675 if (commutative < 0) 2676 commutative = i; 2677 else 2678 gcc_assert (this_insn_is_asm); 2679 } 2680 break; 2681 /* Use of ISDIGIT is tempting here, but it may get expensive because 2682 of locale support we don't want. */ 2683 case '0': case '1': case '2': case '3': case '4': 2684 case '5': case '6': case '7': case '8': case '9': 2685 { 2686 c = strtoul (p - 1, &p, 10); 2687 2688 operands_match[c][i] 2689 = operands_match_p (recog_data.operand[c], 2690 recog_data.operand[i]); 2691 2692 /* An operand may not match itself. */ 2693 gcc_assert (c != i); 2694 2695 /* If C can be commuted with C+1, and C might need to match I, 2696 then C+1 might also need to match I. */ 2697 if (commutative >= 0) 2698 { 2699 if (c == commutative || c == commutative + 1) 2700 { 2701 int other = c + (c == commutative ? 1 : -1); 2702 operands_match[other][i] 2703 = operands_match_p (recog_data.operand[other], 2704 recog_data.operand[i]); 2705 } 2706 if (i == commutative || i == commutative + 1) 2707 { 2708 int other = i + (i == commutative ? 1 : -1); 2709 operands_match[c][other] 2710 = operands_match_p (recog_data.operand[c], 2711 recog_data.operand[other]); 2712 } 2713 /* Note that C is supposed to be less than I. 2714 No need to consider altering both C and I because in 2715 that case we would alter one into the other. */ 2716 } 2717 } 2718 } 2719 } 2720 } 2721 2722 /* Examine each operand that is a memory reference or memory address 2723 and reload parts of the addresses into index registers. 2724 Also here any references to pseudo regs that didn't get hard regs 2725 but are equivalent to constants get replaced in the insn itself 2726 with those constants. Nobody will ever see them again. 2727 2728 Finally, set up the preferred classes of each operand. */ 2729 2730 for (i = 0; i < noperands; i++) 2731 { 2732 RTX_CODE code = GET_CODE (recog_data.operand[i]); 2733 2734 address_reloaded[i] = 0; 2735 address_operand_reloaded[i] = 0; 2736 operand_type[i] = (modified[i] == RELOAD_READ ? RELOAD_FOR_INPUT 2737 : modified[i] == RELOAD_WRITE ? RELOAD_FOR_OUTPUT 2738 : RELOAD_OTHER); 2739 address_type[i] 2740 = (modified[i] == RELOAD_READ ? RELOAD_FOR_INPUT_ADDRESS 2741 : modified[i] == RELOAD_WRITE ? RELOAD_FOR_OUTPUT_ADDRESS 2742 : RELOAD_OTHER); 2743 2744 if (*constraints[i] == 0) 2745 /* Ignore things like match_operator operands. */ 2746 ; 2747 else if (constraints[i][0] == 'p' 2748 || EXTRA_ADDRESS_CONSTRAINT (constraints[i][0], constraints[i])) 2749 { 2750 address_operand_reloaded[i] 2751 = find_reloads_address (recog_data.operand_mode[i], (rtx*) 0, 2752 recog_data.operand[i], 2753 recog_data.operand_loc[i], 2754 i, operand_type[i], ind_levels, insn); 2755 2756 /* If we now have a simple operand where we used to have a 2757 PLUS or MULT, re-recognize and try again. */ 2758 if ((OBJECT_P (*recog_data.operand_loc[i]) 2759 || GET_CODE (*recog_data.operand_loc[i]) == SUBREG) 2760 && (GET_CODE (recog_data.operand[i]) == MULT 2761 || GET_CODE (recog_data.operand[i]) == PLUS)) 2762 { 2763 INSN_CODE (insn) = -1; 2764 retval = find_reloads (insn, replace, ind_levels, live_known, 2765 reload_reg_p); 2766 return retval; 2767 } 2768 2769 recog_data.operand[i] = *recog_data.operand_loc[i]; 2770 substed_operand[i] = recog_data.operand[i]; 2771 2772 /* Address operands are reloaded in their existing mode, 2773 no matter what is specified in the machine description. */ 2774 operand_mode[i] = GET_MODE (recog_data.operand[i]); 2775 } 2776 else if (code == MEM) 2777 { 2778 address_reloaded[i] 2779 = find_reloads_address (GET_MODE (recog_data.operand[i]), 2780 recog_data.operand_loc[i], 2781 XEXP (recog_data.operand[i], 0), 2782 &XEXP (recog_data.operand[i], 0), 2783 i, address_type[i], ind_levels, insn); 2784 recog_data.operand[i] = *recog_data.operand_loc[i]; 2785 substed_operand[i] = recog_data.operand[i]; 2786 } 2787 else if (code == SUBREG) 2788 { 2789 rtx reg = SUBREG_REG (recog_data.operand[i]); 2790 rtx op 2791 = find_reloads_toplev (recog_data.operand[i], i, address_type[i], 2792 ind_levels, 2793 set != 0 2794 && &SET_DEST (set) == recog_data.operand_loc[i], 2795 insn, 2796 &address_reloaded[i]); 2797 2798 /* If we made a MEM to load (a part of) the stackslot of a pseudo 2799 that didn't get a hard register, emit a USE with a REG_EQUAL 2800 note in front so that we might inherit a previous, possibly 2801 wider reload. */ 2802 2803 if (replace 2804 && MEM_P (op) 2805 && REG_P (reg) 2806 && (GET_MODE_SIZE (GET_MODE (reg)) 2807 >= GET_MODE_SIZE (GET_MODE (op)))) 2808 set_unique_reg_note (emit_insn_before (gen_rtx_USE (VOIDmode, reg), 2809 insn), 2810 REG_EQUAL, reg_equiv_memory_loc[REGNO (reg)]); 2811 2812 substed_operand[i] = recog_data.operand[i] = op; 2813 } 2814 else if (code == PLUS || GET_RTX_CLASS (code) == RTX_UNARY) 2815 /* We can get a PLUS as an "operand" as a result of register 2816 elimination. See eliminate_regs and gen_reload. We handle 2817 a unary operator by reloading the operand. */ 2818 substed_operand[i] = recog_data.operand[i] 2819 = find_reloads_toplev (recog_data.operand[i], i, address_type[i], 2820 ind_levels, 0, insn, 2821 &address_reloaded[i]); 2822 else if (code == REG) 2823 { 2824 /* This is equivalent to calling find_reloads_toplev. 2825 The code is duplicated for speed. 2826 When we find a pseudo always equivalent to a constant, 2827 we replace it by the constant. We must be sure, however, 2828 that we don't try to replace it in the insn in which it 2829 is being set. */ 2830 int regno = REGNO (recog_data.operand[i]); 2831 if (reg_equiv_constant[regno] != 0 2832 && (set == 0 || &SET_DEST (set) != recog_data.operand_loc[i])) 2833 { 2834 /* Record the existing mode so that the check if constants are 2835 allowed will work when operand_mode isn't specified. */ 2836 2837 if (operand_mode[i] == VOIDmode) 2838 operand_mode[i] = GET_MODE (recog_data.operand[i]); 2839 2840 substed_operand[i] = recog_data.operand[i] 2841 = reg_equiv_constant[regno]; 2842 } 2843 if (reg_equiv_memory_loc[regno] != 0 2844 && (reg_equiv_address[regno] != 0 || num_not_at_initial_offset)) 2845 /* We need not give a valid is_set_dest argument since the case 2846 of a constant equivalence was checked above. */ 2847 substed_operand[i] = recog_data.operand[i] 2848 = find_reloads_toplev (recog_data.operand[i], i, address_type[i], 2849 ind_levels, 0, insn, 2850 &address_reloaded[i]); 2851 } 2852 /* If the operand is still a register (we didn't replace it with an 2853 equivalent), get the preferred class to reload it into. */ 2854 code = GET_CODE (recog_data.operand[i]); 2855 preferred_class[i] 2856 = ((code == REG && REGNO (recog_data.operand[i]) 2857 >= FIRST_PSEUDO_REGISTER) 2858 ? reg_preferred_class (REGNO (recog_data.operand[i])) 2859 : NO_REGS); 2860 pref_or_nothing[i] 2861 = (code == REG 2862 && REGNO (recog_data.operand[i]) >= FIRST_PSEUDO_REGISTER 2863 && reg_alternate_class (REGNO (recog_data.operand[i])) == NO_REGS); 2864 } 2865 2866 /* If this is simply a copy from operand 1 to operand 0, merge the 2867 preferred classes for the operands. */ 2868 if (set != 0 && noperands >= 2 && recog_data.operand[0] == SET_DEST (set) 2869 && recog_data.operand[1] == SET_SRC (set)) 2870 { 2871 preferred_class[0] = preferred_class[1] 2872 = reg_class_subunion[(int) preferred_class[0]][(int) preferred_class[1]]; 2873 pref_or_nothing[0] |= pref_or_nothing[1]; 2874 pref_or_nothing[1] |= pref_or_nothing[0]; 2875 } 2876 2877 /* Now see what we need for pseudo-regs that didn't get hard regs 2878 or got the wrong kind of hard reg. For this, we must consider 2879 all the operands together against the register constraints. */ 2880 2881 best = MAX_RECOG_OPERANDS * 2 + 600; 2882 2883 swapped = 0; 2884 goal_alternative_swapped = 0; 2885 try_swapped: 2886 2887 /* The constraints are made of several alternatives. 2888 Each operand's constraint looks like foo,bar,... with commas 2889 separating the alternatives. The first alternatives for all 2890 operands go together, the second alternatives go together, etc. 2891 2892 First loop over alternatives. */ 2893 2894 for (this_alternative_number = 0; 2895 this_alternative_number < n_alternatives; 2896 this_alternative_number++) 2897 { 2898 /* Loop over operands for one constraint alternative. */ 2899 /* LOSERS counts those that don't fit this alternative 2900 and would require loading. */ 2901 int losers = 0; 2902 /* BAD is set to 1 if it some operand can't fit this alternative 2903 even after reloading. */ 2904 int bad = 0; 2905 /* REJECT is a count of how undesirable this alternative says it is 2906 if any reloading is required. If the alternative matches exactly 2907 then REJECT is ignored, but otherwise it gets this much 2908 counted against it in addition to the reloading needed. Each 2909 ? counts three times here since we want the disparaging caused by 2910 a bad register class to only count 1/3 as much. */ 2911 int reject = 0; 2912 2913 this_earlyclobber = 0; 2914 2915 for (i = 0; i < noperands; i++) 2916 { 2917 char *p = constraints[i]; 2918 char *end; 2919 int len; 2920 int win = 0; 2921 int did_match = 0; 2922 /* 0 => this operand can be reloaded somehow for this alternative. */ 2923 int badop = 1; 2924 /* 0 => this operand can be reloaded if the alternative allows regs. */ 2925 int winreg = 0; 2926 int c; 2927 int m; 2928 rtx operand = recog_data.operand[i]; 2929 int offset = 0; 2930 /* Nonzero means this is a MEM that must be reloaded into a reg 2931 regardless of what the constraint says. */ 2932 int force_reload = 0; 2933 int offmemok = 0; 2934 /* Nonzero if a constant forced into memory would be OK for this 2935 operand. */ 2936 int constmemok = 0; 2937 int earlyclobber = 0; 2938 2939 /* If the predicate accepts a unary operator, it means that 2940 we need to reload the operand, but do not do this for 2941 match_operator and friends. */ 2942 if (UNARY_P (operand) && *p != 0) 2943 operand = XEXP (operand, 0); 2944 2945 /* If the operand is a SUBREG, extract 2946 the REG or MEM (or maybe even a constant) within. 2947 (Constants can occur as a result of reg_equiv_constant.) */ 2948 2949 while (GET_CODE (operand) == SUBREG) 2950 { 2951 /* Offset only matters when operand is a REG and 2952 it is a hard reg. This is because it is passed 2953 to reg_fits_class_p if it is a REG and all pseudos 2954 return 0 from that function. */ 2955 if (REG_P (SUBREG_REG (operand)) 2956 && REGNO (SUBREG_REG (operand)) < FIRST_PSEUDO_REGISTER) 2957 { 2958 if (!subreg_offset_representable_p 2959 (REGNO (SUBREG_REG (operand)), 2960 GET_MODE (SUBREG_REG (operand)), 2961 SUBREG_BYTE (operand), 2962 GET_MODE (operand))) 2963 force_reload = 1; 2964 offset += subreg_regno_offset (REGNO (SUBREG_REG (operand)), 2965 GET_MODE (SUBREG_REG (operand)), 2966 SUBREG_BYTE (operand), 2967 GET_MODE (operand)); 2968 } 2969 operand = SUBREG_REG (operand); 2970 /* Force reload if this is a constant or PLUS or if there may 2971 be a problem accessing OPERAND in the outer mode. */ 2972 if (CONSTANT_P (operand) 2973 || GET_CODE (operand) == PLUS 2974 /* We must force a reload of paradoxical SUBREGs 2975 of a MEM because the alignment of the inner value 2976 may not be enough to do the outer reference. On 2977 big-endian machines, it may also reference outside 2978 the object. 2979 2980 On machines that extend byte operations and we have a 2981 SUBREG where both the inner and outer modes are no wider 2982 than a word and the inner mode is narrower, is integral, 2983 and gets extended when loaded from memory, combine.c has 2984 made assumptions about the behavior of the machine in such 2985 register access. If the data is, in fact, in memory we 2986 must always load using the size assumed to be in the 2987 register and let the insn do the different-sized 2988 accesses. 2989 2990 This is doubly true if WORD_REGISTER_OPERATIONS. In 2991 this case eliminate_regs has left non-paradoxical 2992 subregs for push_reload to see. Make sure it does 2993 by forcing the reload. 2994 2995 ??? When is it right at this stage to have a subreg 2996 of a mem that is _not_ to be handled specially? IMO 2997 those should have been reduced to just a mem. */ 2998 || ((MEM_P (operand) 2999 || (REG_P (operand) 3000 && REGNO (operand) >= FIRST_PSEUDO_REGISTER)) 3001#ifndef WORD_REGISTER_OPERATIONS 3002 && (((GET_MODE_BITSIZE (GET_MODE (operand)) 3003 < BIGGEST_ALIGNMENT) 3004 && (GET_MODE_SIZE (operand_mode[i]) 3005 > GET_MODE_SIZE (GET_MODE (operand)))) 3006 || BYTES_BIG_ENDIAN 3007#ifdef LOAD_EXTEND_OP 3008 || (GET_MODE_SIZE (operand_mode[i]) <= UNITS_PER_WORD 3009 && (GET_MODE_SIZE (GET_MODE (operand)) 3010 <= UNITS_PER_WORD) 3011 && (GET_MODE_SIZE (operand_mode[i]) 3012 > GET_MODE_SIZE (GET_MODE (operand))) 3013 && INTEGRAL_MODE_P (GET_MODE (operand)) 3014 && LOAD_EXTEND_OP (GET_MODE (operand)) != UNKNOWN) 3015#endif 3016 ) 3017#endif 3018 ) 3019 ) 3020 force_reload = 1; 3021 } 3022 3023 this_alternative[i] = (int) NO_REGS; 3024 this_alternative_win[i] = 0; 3025 this_alternative_match_win[i] = 0; 3026 this_alternative_offmemok[i] = 0; 3027 this_alternative_earlyclobber[i] = 0; 3028 this_alternative_matches[i] = -1; 3029 3030 /* An empty constraint or empty alternative 3031 allows anything which matched the pattern. */ 3032 if (*p == 0 || *p == ',') 3033 win = 1, badop = 0; 3034 3035 /* Scan this alternative's specs for this operand; 3036 set WIN if the operand fits any letter in this alternative. 3037 Otherwise, clear BADOP if this operand could 3038 fit some letter after reloads, 3039 or set WINREG if this operand could fit after reloads 3040 provided the constraint allows some registers. */ 3041 3042 do 3043 switch ((c = *p, len = CONSTRAINT_LEN (c, p)), c) 3044 { 3045 case '\0': 3046 len = 0; 3047 break; 3048 case ',': 3049 c = '\0'; 3050 break; 3051 3052 case '=': case '+': case '*': 3053 break; 3054 3055 case '%': 3056 /* We only support one commutative marker, the first 3057 one. We already set commutative above. */ 3058 break; 3059 3060 case '?': 3061 reject += 6; 3062 break; 3063 3064 case '!': 3065 reject = 600; 3066 break; 3067 3068 case '#': 3069 /* Ignore rest of this alternative as far as 3070 reloading is concerned. */ 3071 do 3072 p++; 3073 while (*p && *p != ','); 3074 len = 0; 3075 break; 3076 3077 case '0': case '1': case '2': case '3': case '4': 3078 case '5': case '6': case '7': case '8': case '9': 3079 m = strtoul (p, &end, 10); 3080 p = end; 3081 len = 0; 3082 3083 this_alternative_matches[i] = m; 3084 /* We are supposed to match a previous operand. 3085 If we do, we win if that one did. 3086 If we do not, count both of the operands as losers. 3087 (This is too conservative, since most of the time 3088 only a single reload insn will be needed to make 3089 the two operands win. As a result, this alternative 3090 may be rejected when it is actually desirable.) */ 3091 if ((swapped && (m != commutative || i != commutative + 1)) 3092 /* If we are matching as if two operands were swapped, 3093 also pretend that operands_match had been computed 3094 with swapped. 3095 But if I is the second of those and C is the first, 3096 don't exchange them, because operands_match is valid 3097 only on one side of its diagonal. */ 3098 ? (operands_match 3099 [(m == commutative || m == commutative + 1) 3100 ? 2 * commutative + 1 - m : m] 3101 [(i == commutative || i == commutative + 1) 3102 ? 2 * commutative + 1 - i : i]) 3103 : operands_match[m][i]) 3104 { 3105 /* If we are matching a non-offsettable address where an 3106 offsettable address was expected, then we must reject 3107 this combination, because we can't reload it. */ 3108 if (this_alternative_offmemok[m] 3109 && MEM_P (recog_data.operand[m]) 3110 && this_alternative[m] == (int) NO_REGS 3111 && ! this_alternative_win[m]) 3112 bad = 1; 3113 3114 did_match = this_alternative_win[m]; 3115 } 3116 else 3117 { 3118 /* Operands don't match. */ 3119 rtx value; 3120 int loc1, loc2; 3121 /* Retroactively mark the operand we had to match 3122 as a loser, if it wasn't already. */ 3123 if (this_alternative_win[m]) 3124 losers++; 3125 this_alternative_win[m] = 0; 3126 if (this_alternative[m] == (int) NO_REGS) 3127 bad = 1; 3128 /* But count the pair only once in the total badness of 3129 this alternative, if the pair can be a dummy reload. 3130 The pointers in operand_loc are not swapped; swap 3131 them by hand if necessary. */ 3132 if (swapped && i == commutative) 3133 loc1 = commutative + 1; 3134 else if (swapped && i == commutative + 1) 3135 loc1 = commutative; 3136 else 3137 loc1 = i; 3138 if (swapped && m == commutative) 3139 loc2 = commutative + 1; 3140 else if (swapped && m == commutative + 1) 3141 loc2 = commutative; 3142 else 3143 loc2 = m; 3144 value 3145 = find_dummy_reload (recog_data.operand[i], 3146 recog_data.operand[m], 3147 recog_data.operand_loc[loc1], 3148 recog_data.operand_loc[loc2], 3149 operand_mode[i], operand_mode[m], 3150 this_alternative[m], -1, 3151 this_alternative_earlyclobber[m]); 3152 3153 if (value != 0) 3154 losers--; 3155 } 3156 /* This can be fixed with reloads if the operand 3157 we are supposed to match can be fixed with reloads. */ 3158 badop = 0; 3159 this_alternative[i] = this_alternative[m]; 3160 3161 /* If we have to reload this operand and some previous 3162 operand also had to match the same thing as this 3163 operand, we don't know how to do that. So reject this 3164 alternative. */ 3165 if (! did_match || force_reload) 3166 for (j = 0; j < i; j++) 3167 if (this_alternative_matches[j] 3168 == this_alternative_matches[i]) 3169 badop = 1; 3170 break; 3171 3172 case 'p': 3173 /* All necessary reloads for an address_operand 3174 were handled in find_reloads_address. */ 3175 this_alternative[i] 3176 = (int) base_reg_class (VOIDmode, ADDRESS, SCRATCH); 3177 win = 1; 3178 badop = 0; 3179 break; 3180 3181 case 'm': 3182 if (force_reload) 3183 break; 3184 if (MEM_P (operand) 3185 || (REG_P (operand) 3186 && REGNO (operand) >= FIRST_PSEUDO_REGISTER 3187 && reg_renumber[REGNO (operand)] < 0)) 3188 win = 1; 3189 if (CONST_POOL_OK_P (operand)) 3190 badop = 0; 3191 constmemok = 1; 3192 break; 3193 3194 case '<': 3195 if (MEM_P (operand) 3196 && ! address_reloaded[i] 3197 && (GET_CODE (XEXP (operand, 0)) == PRE_DEC 3198 || GET_CODE (XEXP (operand, 0)) == POST_DEC)) 3199 win = 1; 3200 break; 3201 3202 case '>': 3203 if (MEM_P (operand) 3204 && ! address_reloaded[i] 3205 && (GET_CODE (XEXP (operand, 0)) == PRE_INC 3206 || GET_CODE (XEXP (operand, 0)) == POST_INC)) 3207 win = 1; 3208 break; 3209 3210 /* Memory operand whose address is not offsettable. */ 3211 case 'V': 3212 if (force_reload) 3213 break; 3214 if (MEM_P (operand) 3215 && ! (ind_levels ? offsettable_memref_p (operand) 3216 : offsettable_nonstrict_memref_p (operand)) 3217 /* Certain mem addresses will become offsettable 3218 after they themselves are reloaded. This is important; 3219 we don't want our own handling of unoffsettables 3220 to override the handling of reg_equiv_address. */ 3221 && !(REG_P (XEXP (operand, 0)) 3222 && (ind_levels == 0 3223 || reg_equiv_address[REGNO (XEXP (operand, 0))] != 0))) 3224 win = 1; 3225 break; 3226 3227 /* Memory operand whose address is offsettable. */ 3228 case 'o': 3229 if (force_reload) 3230 break; 3231 if ((MEM_P (operand) 3232 /* If IND_LEVELS, find_reloads_address won't reload a 3233 pseudo that didn't get a hard reg, so we have to 3234 reject that case. */ 3235 && ((ind_levels ? offsettable_memref_p (operand) 3236 : offsettable_nonstrict_memref_p (operand)) 3237 /* A reloaded address is offsettable because it is now 3238 just a simple register indirect. */ 3239 || address_reloaded[i] == 1)) 3240 || (REG_P (operand) 3241 && REGNO (operand) >= FIRST_PSEUDO_REGISTER 3242 && reg_renumber[REGNO (operand)] < 0 3243 /* If reg_equiv_address is nonzero, we will be 3244 loading it into a register; hence it will be 3245 offsettable, but we cannot say that reg_equiv_mem 3246 is offsettable without checking. */ 3247 && ((reg_equiv_mem[REGNO (operand)] != 0 3248 && offsettable_memref_p (reg_equiv_mem[REGNO (operand)])) 3249 || (reg_equiv_address[REGNO (operand)] != 0)))) 3250 win = 1; 3251 if (CONST_POOL_OK_P (operand) 3252 || MEM_P (operand)) 3253 badop = 0; 3254 constmemok = 1; 3255 offmemok = 1; 3256 break; 3257 3258 case '&': 3259 /* Output operand that is stored before the need for the 3260 input operands (and their index registers) is over. */ 3261 earlyclobber = 1, this_earlyclobber = 1; 3262 break; 3263 3264 case 'E': 3265 case 'F': 3266 if (GET_CODE (operand) == CONST_DOUBLE 3267 || (GET_CODE (operand) == CONST_VECTOR 3268 && (GET_MODE_CLASS (GET_MODE (operand)) 3269 == MODE_VECTOR_FLOAT))) 3270 win = 1; 3271 break; 3272 3273 case 'G': 3274 case 'H': 3275 if (GET_CODE (operand) == CONST_DOUBLE 3276 && CONST_DOUBLE_OK_FOR_CONSTRAINT_P (operand, c, p)) 3277 win = 1; 3278 break; 3279 3280 case 's': 3281 if (GET_CODE (operand) == CONST_INT 3282 || (GET_CODE (operand) == CONST_DOUBLE 3283 && GET_MODE (operand) == VOIDmode)) 3284 break; 3285 case 'i': 3286 if (CONSTANT_P (operand) 3287 && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (operand))) 3288 win = 1; 3289 break; 3290 3291 case 'n': 3292 if (GET_CODE (operand) == CONST_INT 3293 || (GET_CODE (operand) == CONST_DOUBLE 3294 && GET_MODE (operand) == VOIDmode)) 3295 win = 1; 3296 break; 3297 3298 case 'I': 3299 case 'J': 3300 case 'K': 3301 case 'L': 3302 case 'M': 3303 case 'N': 3304 case 'O': 3305 case 'P': 3306 if (GET_CODE (operand) == CONST_INT 3307 && CONST_OK_FOR_CONSTRAINT_P (INTVAL (operand), c, p)) 3308 win = 1; 3309 break; 3310 3311 case 'X': 3312 force_reload = 0; 3313 win = 1; 3314 break; 3315 3316 case 'g': 3317 if (! force_reload 3318 /* A PLUS is never a valid operand, but reload can make 3319 it from a register when eliminating registers. */ 3320 && GET_CODE (operand) != PLUS 3321 /* A SCRATCH is not a valid operand. */ 3322 && GET_CODE (operand) != SCRATCH 3323 && (! CONSTANT_P (operand) 3324 || ! flag_pic 3325 || LEGITIMATE_PIC_OPERAND_P (operand)) 3326 && (GENERAL_REGS == ALL_REGS 3327 || !REG_P (operand) 3328 || (REGNO (operand) >= FIRST_PSEUDO_REGISTER 3329 && reg_renumber[REGNO (operand)] < 0))) 3330 win = 1; 3331 /* Drop through into 'r' case. */ 3332 3333 case 'r': 3334 this_alternative[i] 3335 = (int) reg_class_subunion[this_alternative[i]][(int) GENERAL_REGS]; 3336 goto reg; 3337 3338 default: 3339 if (REG_CLASS_FROM_CONSTRAINT (c, p) == NO_REGS) 3340 { 3341#ifdef EXTRA_CONSTRAINT_STR 3342 if (EXTRA_MEMORY_CONSTRAINT (c, p)) 3343 { 3344 if (force_reload) 3345 break; 3346 if (EXTRA_CONSTRAINT_STR (operand, c, p)) 3347 win = 1; 3348 /* If the address was already reloaded, 3349 we win as well. */ 3350 else if (MEM_P (operand) 3351 && address_reloaded[i] == 1) 3352 win = 1; 3353 /* Likewise if the address will be reloaded because 3354 reg_equiv_address is nonzero. For reg_equiv_mem 3355 we have to check. */ 3356 else if (REG_P (operand) 3357 && REGNO (operand) >= FIRST_PSEUDO_REGISTER 3358 && reg_renumber[REGNO (operand)] < 0 3359 && ((reg_equiv_mem[REGNO (operand)] != 0 3360 && EXTRA_CONSTRAINT_STR (reg_equiv_mem[REGNO (operand)], c, p)) 3361 || (reg_equiv_address[REGNO (operand)] != 0))) 3362 win = 1; 3363 3364 /* If we didn't already win, we can reload 3365 constants via force_const_mem, and other 3366 MEMs by reloading the address like for 'o'. */ 3367 if (CONST_POOL_OK_P (operand) 3368 || MEM_P (operand)) 3369 badop = 0; 3370 constmemok = 1; 3371 offmemok = 1; 3372 break; 3373 } 3374 if (EXTRA_ADDRESS_CONSTRAINT (c, p)) 3375 { 3376 if (EXTRA_CONSTRAINT_STR (operand, c, p)) 3377 win = 1; 3378 3379 /* If we didn't already win, we can reload 3380 the address into a base register. */ 3381 this_alternative[i] 3382 = (int) base_reg_class (VOIDmode, ADDRESS, SCRATCH); 3383 badop = 0; 3384 break; 3385 } 3386 3387 if (EXTRA_CONSTRAINT_STR (operand, c, p)) 3388 win = 1; 3389#endif 3390 break; 3391 } 3392 3393 this_alternative[i] 3394 = (int) (reg_class_subunion 3395 [this_alternative[i]] 3396 [(int) REG_CLASS_FROM_CONSTRAINT (c, p)]); 3397 reg: 3398 if (GET_MODE (operand) == BLKmode) 3399 break; 3400 winreg = 1; 3401 if (REG_P (operand) 3402 && reg_fits_class_p (operand, this_alternative[i], 3403 offset, GET_MODE (recog_data.operand[i]))) 3404 win = 1; 3405 break; 3406 } 3407 while ((p += len), c); 3408 3409 constraints[i] = p; 3410 3411 /* If this operand could be handled with a reg, 3412 and some reg is allowed, then this operand can be handled. */ 3413 if (winreg && this_alternative[i] != (int) NO_REGS) 3414 badop = 0; 3415 3416 /* Record which operands fit this alternative. */ 3417 this_alternative_earlyclobber[i] = earlyclobber; 3418 if (win && ! force_reload) 3419 this_alternative_win[i] = 1; 3420 else if (did_match && ! force_reload) 3421 this_alternative_match_win[i] = 1; 3422 else 3423 { 3424 int const_to_mem = 0; 3425 3426 this_alternative_offmemok[i] = offmemok; 3427 losers++; 3428 if (badop) 3429 bad = 1; 3430 /* Alternative loses if it has no regs for a reg operand. */ 3431 if (REG_P (operand) 3432 && this_alternative[i] == (int) NO_REGS 3433 && this_alternative_matches[i] < 0) 3434 bad = 1; 3435 3436 /* If this is a constant that is reloaded into the desired 3437 class by copying it to memory first, count that as another 3438 reload. This is consistent with other code and is 3439 required to avoid choosing another alternative when 3440 the constant is moved into memory by this function on 3441 an early reload pass. Note that the test here is 3442 precisely the same as in the code below that calls 3443 force_const_mem. */ 3444 if (CONST_POOL_OK_P (operand) 3445 && ((PREFERRED_RELOAD_CLASS (operand, 3446 (enum reg_class) this_alternative[i]) 3447 == NO_REGS) 3448 || no_input_reloads) 3449 && operand_mode[i] != VOIDmode) 3450 { 3451 const_to_mem = 1; 3452 if (this_alternative[i] != (int) NO_REGS) 3453 losers++; 3454 } 3455 3456 /* Alternative loses if it requires a type of reload not 3457 permitted for this insn. We can always reload SCRATCH 3458 and objects with a REG_UNUSED note. */ 3459 if (GET_CODE (operand) != SCRATCH 3460 && modified[i] != RELOAD_READ && no_output_reloads 3461 && ! find_reg_note (insn, REG_UNUSED, operand)) 3462 bad = 1; 3463 else if (modified[i] != RELOAD_WRITE && no_input_reloads 3464 && ! const_to_mem) 3465 bad = 1; 3466 3467 /* If we can't reload this value at all, reject this 3468 alternative. Note that we could also lose due to 3469 LIMIT_RELOAD_CLASS, but we don't check that 3470 here. */ 3471 3472 if (! CONSTANT_P (operand) 3473 && (enum reg_class) this_alternative[i] != NO_REGS) 3474 { 3475 if (PREFERRED_RELOAD_CLASS 3476 (operand, (enum reg_class) this_alternative[i]) 3477 == NO_REGS) 3478 reject = 600; 3479 3480#ifdef PREFERRED_OUTPUT_RELOAD_CLASS 3481 if (operand_type[i] == RELOAD_FOR_OUTPUT 3482 && PREFERRED_OUTPUT_RELOAD_CLASS 3483 (operand, (enum reg_class) this_alternative[i]) 3484 == NO_REGS) 3485 reject = 600; 3486#endif 3487 } 3488 3489 /* We prefer to reload pseudos over reloading other things, 3490 since such reloads may be able to be eliminated later. 3491 If we are reloading a SCRATCH, we won't be generating any 3492 insns, just using a register, so it is also preferred. 3493 So bump REJECT in other cases. Don't do this in the 3494 case where we are forcing a constant into memory and 3495 it will then win since we don't want to have a different 3496 alternative match then. */ 3497 if (! (REG_P (operand) 3498 && REGNO (operand) >= FIRST_PSEUDO_REGISTER) 3499 && GET_CODE (operand) != SCRATCH 3500 && ! (const_to_mem && constmemok)) 3501 reject += 2; 3502 3503 /* Input reloads can be inherited more often than output 3504 reloads can be removed, so penalize output reloads. */ 3505 if (operand_type[i] != RELOAD_FOR_INPUT 3506 && GET_CODE (operand) != SCRATCH) 3507 reject++; 3508 } 3509 3510 /* If this operand is a pseudo register that didn't get a hard 3511 reg and this alternative accepts some register, see if the 3512 class that we want is a subset of the preferred class for this 3513 register. If not, but it intersects that class, use the 3514 preferred class instead. If it does not intersect the preferred 3515 class, show that usage of this alternative should be discouraged; 3516 it will be discouraged more still if the register is `preferred 3517 or nothing'. We do this because it increases the chance of 3518 reusing our spill register in a later insn and avoiding a pair 3519 of memory stores and loads. 3520 3521 Don't bother with this if this alternative will accept this 3522 operand. 3523 3524 Don't do this for a multiword operand, since it is only a 3525 small win and has the risk of requiring more spill registers, 3526 which could cause a large loss. 3527 3528 Don't do this if the preferred class has only one register 3529 because we might otherwise exhaust the class. */ 3530 3531 if (! win && ! did_match 3532 && this_alternative[i] != (int) NO_REGS 3533 && GET_MODE_SIZE (operand_mode[i]) <= UNITS_PER_WORD 3534 && reg_class_size [(int) preferred_class[i]] > 0 3535 && ! SMALL_REGISTER_CLASS_P (preferred_class[i])) 3536 { 3537 if (! reg_class_subset_p (this_alternative[i], 3538 preferred_class[i])) 3539 { 3540 /* Since we don't have a way of forming the intersection, 3541 we just do something special if the preferred class 3542 is a subset of the class we have; that's the most 3543 common case anyway. */ 3544 if (reg_class_subset_p (preferred_class[i], 3545 this_alternative[i])) 3546 this_alternative[i] = (int) preferred_class[i]; 3547 else 3548 reject += (2 + 2 * pref_or_nothing[i]); 3549 } 3550 } 3551 } 3552 3553 /* Now see if any output operands that are marked "earlyclobber" 3554 in this alternative conflict with any input operands 3555 or any memory addresses. */ 3556 3557 for (i = 0; i < noperands; i++) 3558 if (this_alternative_earlyclobber[i] 3559 && (this_alternative_win[i] || this_alternative_match_win[i])) 3560 { 3561 struct decomposition early_data; 3562 3563 early_data = decompose (recog_data.operand[i]); 3564 3565 gcc_assert (modified[i] != RELOAD_READ); 3566 3567 if (this_alternative[i] == NO_REGS) 3568 { 3569 this_alternative_earlyclobber[i] = 0; 3570 gcc_assert (this_insn_is_asm); 3571 error_for_asm (this_insn, 3572 "%<&%> constraint used with no register class"); 3573 } 3574 3575 for (j = 0; j < noperands; j++) 3576 /* Is this an input operand or a memory ref? */ 3577 if ((MEM_P (recog_data.operand[j]) 3578 || modified[j] != RELOAD_WRITE) 3579 && j != i 3580 /* Ignore things like match_operator operands. */ 3581 && *recog_data.constraints[j] != 0 3582 /* Don't count an input operand that is constrained to match 3583 the early clobber operand. */ 3584 && ! (this_alternative_matches[j] == i 3585 && rtx_equal_p (recog_data.operand[i], 3586 recog_data.operand[j])) 3587 /* Is it altered by storing the earlyclobber operand? */ 3588 && !immune_p (recog_data.operand[j], recog_data.operand[i], 3589 early_data)) 3590 { 3591 /* If the output is in a non-empty few-regs class, 3592 it's costly to reload it, so reload the input instead. */ 3593 if (SMALL_REGISTER_CLASS_P (this_alternative[i]) 3594 && (REG_P (recog_data.operand[j]) 3595 || GET_CODE (recog_data.operand[j]) == SUBREG)) 3596 { 3597 losers++; 3598 this_alternative_win[j] = 0; 3599 this_alternative_match_win[j] = 0; 3600 } 3601 else 3602 break; 3603 } 3604 /* If an earlyclobber operand conflicts with something, 3605 it must be reloaded, so request this and count the cost. */ 3606 if (j != noperands) 3607 { 3608 losers++; 3609 this_alternative_win[i] = 0; 3610 this_alternative_match_win[j] = 0; 3611 for (j = 0; j < noperands; j++) 3612 if (this_alternative_matches[j] == i 3613 && this_alternative_match_win[j]) 3614 { 3615 this_alternative_win[j] = 0; 3616 this_alternative_match_win[j] = 0; 3617 losers++; 3618 } 3619 } 3620 } 3621 3622 /* If one alternative accepts all the operands, no reload required, 3623 choose that alternative; don't consider the remaining ones. */ 3624 if (losers == 0) 3625 { 3626 /* Unswap these so that they are never swapped at `finish'. */ 3627 if (commutative >= 0) 3628 { 3629 recog_data.operand[commutative] = substed_operand[commutative]; 3630 recog_data.operand[commutative + 1] 3631 = substed_operand[commutative + 1]; 3632 } 3633 for (i = 0; i < noperands; i++) 3634 { 3635 goal_alternative_win[i] = this_alternative_win[i]; 3636 goal_alternative_match_win[i] = this_alternative_match_win[i]; 3637 goal_alternative[i] = this_alternative[i]; 3638 goal_alternative_offmemok[i] = this_alternative_offmemok[i]; 3639 goal_alternative_matches[i] = this_alternative_matches[i]; 3640 goal_alternative_earlyclobber[i] 3641 = this_alternative_earlyclobber[i]; 3642 } 3643 goal_alternative_number = this_alternative_number; 3644 goal_alternative_swapped = swapped; 3645 goal_earlyclobber = this_earlyclobber; 3646 goto finish; 3647 } 3648 3649 /* REJECT, set by the ! and ? constraint characters and when a register 3650 would be reloaded into a non-preferred class, discourages the use of 3651 this alternative for a reload goal. REJECT is incremented by six 3652 for each ? and two for each non-preferred class. */ 3653 losers = losers * 6 + reject; 3654 3655 /* If this alternative can be made to work by reloading, 3656 and it needs less reloading than the others checked so far, 3657 record it as the chosen goal for reloading. */ 3658 if (! bad && best > losers) 3659 { 3660 for (i = 0; i < noperands; i++) 3661 { 3662 goal_alternative[i] = this_alternative[i]; 3663 goal_alternative_win[i] = this_alternative_win[i]; 3664 goal_alternative_match_win[i] = this_alternative_match_win[i]; 3665 goal_alternative_offmemok[i] = this_alternative_offmemok[i]; 3666 goal_alternative_matches[i] = this_alternative_matches[i]; 3667 goal_alternative_earlyclobber[i] 3668 = this_alternative_earlyclobber[i]; 3669 } 3670 goal_alternative_swapped = swapped; 3671 best = losers; 3672 goal_alternative_number = this_alternative_number; 3673 goal_earlyclobber = this_earlyclobber; 3674 } 3675 } 3676 3677 /* If insn is commutative (it's safe to exchange a certain pair of operands) 3678 then we need to try each alternative twice, 3679 the second time matching those two operands 3680 as if we had exchanged them. 3681 To do this, really exchange them in operands. 3682 3683 If we have just tried the alternatives the second time, 3684 return operands to normal and drop through. */ 3685 3686 if (commutative >= 0) 3687 { 3688 swapped = !swapped; 3689 if (swapped) 3690 { 3691 enum reg_class tclass; 3692 int t; 3693 3694 recog_data.operand[commutative] = substed_operand[commutative + 1]; 3695 recog_data.operand[commutative + 1] = substed_operand[commutative]; 3696 /* Swap the duplicates too. */ 3697 for (i = 0; i < recog_data.n_dups; i++) 3698 if (recog_data.dup_num[i] == commutative 3699 || recog_data.dup_num[i] == commutative + 1) 3700 *recog_data.dup_loc[i] 3701 = recog_data.operand[(int) recog_data.dup_num[i]]; 3702 3703 tclass = preferred_class[commutative]; 3704 preferred_class[commutative] = preferred_class[commutative + 1]; 3705 preferred_class[commutative + 1] = tclass; 3706 3707 t = pref_or_nothing[commutative]; 3708 pref_or_nothing[commutative] = pref_or_nothing[commutative + 1]; 3709 pref_or_nothing[commutative + 1] = t; 3710 3711 t = address_reloaded[commutative]; 3712 address_reloaded[commutative] = address_reloaded[commutative + 1]; 3713 address_reloaded[commutative + 1] = t; 3714 3715 memcpy (constraints, recog_data.constraints, 3716 noperands * sizeof (char *)); 3717 goto try_swapped; 3718 } 3719 else 3720 { 3721 recog_data.operand[commutative] = substed_operand[commutative]; 3722 recog_data.operand[commutative + 1] 3723 = substed_operand[commutative + 1]; 3724 /* Unswap the duplicates too. */ 3725 for (i = 0; i < recog_data.n_dups; i++) 3726 if (recog_data.dup_num[i] == commutative 3727 || recog_data.dup_num[i] == commutative + 1) 3728 *recog_data.dup_loc[i] 3729 = recog_data.operand[(int) recog_data.dup_num[i]]; 3730 } 3731 } 3732 3733 /* The operands don't meet the constraints. 3734 goal_alternative describes the alternative 3735 that we could reach by reloading the fewest operands. 3736 Reload so as to fit it. */ 3737 3738 if (best == MAX_RECOG_OPERANDS * 2 + 600) 3739 { 3740 /* No alternative works with reloads?? */ 3741 if (insn_code_number >= 0) 3742 fatal_insn ("unable to generate reloads for:", insn); 3743 error_for_asm (insn, "inconsistent operand constraints in an %<asm%>"); 3744 /* Avoid further trouble with this insn. */ 3745 PATTERN (insn) = gen_rtx_USE (VOIDmode, const0_rtx); 3746 n_reloads = 0; 3747 return 0; 3748 } 3749 3750 /* Jump to `finish' from above if all operands are valid already. 3751 In that case, goal_alternative_win is all 1. */ 3752 finish: 3753 3754 /* Right now, for any pair of operands I and J that are required to match, 3755 with I < J, 3756 goal_alternative_matches[J] is I. 3757 Set up goal_alternative_matched as the inverse function: 3758 goal_alternative_matched[I] = J. */ 3759 3760 for (i = 0; i < noperands; i++) 3761 goal_alternative_matched[i] = -1; 3762 3763 for (i = 0; i < noperands; i++) 3764 if (! goal_alternative_win[i] 3765 && goal_alternative_matches[i] >= 0) 3766 goal_alternative_matched[goal_alternative_matches[i]] = i; 3767 3768 for (i = 0; i < noperands; i++) 3769 goal_alternative_win[i] |= goal_alternative_match_win[i]; 3770 3771 /* If the best alternative is with operands 1 and 2 swapped, 3772 consider them swapped before reporting the reloads. Update the 3773 operand numbers of any reloads already pushed. */ 3774 3775 if (goal_alternative_swapped) 3776 { 3777 rtx tem; 3778 3779 tem = substed_operand[commutative]; 3780 substed_operand[commutative] = substed_operand[commutative + 1]; 3781 substed_operand[commutative + 1] = tem; 3782 tem = recog_data.operand[commutative]; 3783 recog_data.operand[commutative] = recog_data.operand[commutative + 1]; 3784 recog_data.operand[commutative + 1] = tem; 3785 tem = *recog_data.operand_loc[commutative]; 3786 *recog_data.operand_loc[commutative] 3787 = *recog_data.operand_loc[commutative + 1]; 3788 *recog_data.operand_loc[commutative + 1] = tem; 3789 3790 for (i = 0; i < n_reloads; i++) 3791 { 3792 if (rld[i].opnum == commutative) 3793 rld[i].opnum = commutative + 1; 3794 else if (rld[i].opnum == commutative + 1) 3795 rld[i].opnum = commutative; 3796 } 3797 } 3798 3799 for (i = 0; i < noperands; i++) 3800 { 3801 operand_reloadnum[i] = -1; 3802 3803 /* If this is an earlyclobber operand, we need to widen the scope. 3804 The reload must remain valid from the start of the insn being 3805 reloaded until after the operand is stored into its destination. 3806 We approximate this with RELOAD_OTHER even though we know that we 3807 do not conflict with RELOAD_FOR_INPUT_ADDRESS reloads. 3808 3809 One special case that is worth checking is when we have an 3810 output that is earlyclobber but isn't used past the insn (typically 3811 a SCRATCH). In this case, we only need have the reload live 3812 through the insn itself, but not for any of our input or output 3813 reloads. 3814 But we must not accidentally narrow the scope of an existing 3815 RELOAD_OTHER reload - leave these alone. 3816 3817 In any case, anything needed to address this operand can remain 3818 however they were previously categorized. */ 3819 3820 if (goal_alternative_earlyclobber[i] && operand_type[i] != RELOAD_OTHER) 3821 operand_type[i] 3822 = (find_reg_note (insn, REG_UNUSED, recog_data.operand[i]) 3823 ? RELOAD_FOR_INSN : RELOAD_OTHER); 3824 } 3825 3826 /* Any constants that aren't allowed and can't be reloaded 3827 into registers are here changed into memory references. */ 3828 for (i = 0; i < noperands; i++) 3829 if (! goal_alternative_win[i] 3830 && CONST_POOL_OK_P (recog_data.operand[i]) 3831 && ((PREFERRED_RELOAD_CLASS (recog_data.operand[i], 3832 (enum reg_class) goal_alternative[i]) 3833 == NO_REGS) 3834 || no_input_reloads) 3835 && operand_mode[i] != VOIDmode) 3836 { 3837 substed_operand[i] = recog_data.operand[i] 3838 = find_reloads_toplev (force_const_mem (operand_mode[i], 3839 recog_data.operand[i]), 3840 i, address_type[i], ind_levels, 0, insn, 3841 NULL); 3842 if (alternative_allows_memconst (recog_data.constraints[i], 3843 goal_alternative_number)) 3844 goal_alternative_win[i] = 1; 3845 } 3846 3847 /* Likewise any invalid constants appearing as operand of a PLUS 3848 that is to be reloaded. */ 3849 for (i = 0; i < noperands; i++) 3850 if (! goal_alternative_win[i] 3851 && GET_CODE (recog_data.operand[i]) == PLUS 3852 && CONST_POOL_OK_P (XEXP (recog_data.operand[i], 1)) 3853 && (PREFERRED_RELOAD_CLASS (XEXP (recog_data.operand[i], 1), 3854 (enum reg_class) goal_alternative[i]) 3855 == NO_REGS) 3856 && operand_mode[i] != VOIDmode) 3857 { 3858 rtx tem = force_const_mem (operand_mode[i], 3859 XEXP (recog_data.operand[i], 1)); 3860 tem = gen_rtx_PLUS (operand_mode[i], 3861 XEXP (recog_data.operand[i], 0), tem); 3862 3863 substed_operand[i] = recog_data.operand[i] 3864 = find_reloads_toplev (tem, i, address_type[i], 3865 ind_levels, 0, insn, NULL); 3866 } 3867 3868 /* Record the values of the earlyclobber operands for the caller. */ 3869 if (goal_earlyclobber) 3870 for (i = 0; i < noperands; i++) 3871 if (goal_alternative_earlyclobber[i]) 3872 reload_earlyclobbers[n_earlyclobbers++] = recog_data.operand[i]; 3873 3874 /* Now record reloads for all the operands that need them. */ 3875 for (i = 0; i < noperands; i++) 3876 if (! goal_alternative_win[i]) 3877 { 3878 /* Operands that match previous ones have already been handled. */ 3879 if (goal_alternative_matches[i] >= 0) 3880 ; 3881 /* Handle an operand with a nonoffsettable address 3882 appearing where an offsettable address will do 3883 by reloading the address into a base register. 3884 3885 ??? We can also do this when the operand is a register and 3886 reg_equiv_mem is not offsettable, but this is a bit tricky, 3887 so we don't bother with it. It may not be worth doing. */ 3888 else if (goal_alternative_matched[i] == -1 3889 && goal_alternative_offmemok[i] 3890 && MEM_P (recog_data.operand[i])) 3891 { 3892 /* If the address to be reloaded is a VOIDmode constant, 3893 use Pmode as mode of the reload register, as would have 3894 been done by find_reloads_address. */ 3895 enum machine_mode address_mode; 3896 address_mode = GET_MODE (XEXP (recog_data.operand[i], 0)); 3897 if (address_mode == VOIDmode) 3898 address_mode = Pmode; 3899 3900 operand_reloadnum[i] 3901 = push_reload (XEXP (recog_data.operand[i], 0), NULL_RTX, 3902 &XEXP (recog_data.operand[i], 0), (rtx*) 0, 3903 base_reg_class (VOIDmode, MEM, SCRATCH), 3904 address_mode, 3905 VOIDmode, 0, 0, i, RELOAD_FOR_INPUT); 3906 rld[operand_reloadnum[i]].inc 3907 = GET_MODE_SIZE (GET_MODE (recog_data.operand[i])); 3908 3909 /* If this operand is an output, we will have made any 3910 reloads for its address as RELOAD_FOR_OUTPUT_ADDRESS, but 3911 now we are treating part of the operand as an input, so 3912 we must change these to RELOAD_FOR_INPUT_ADDRESS. */ 3913 3914 if (modified[i] == RELOAD_WRITE) 3915 { 3916 for (j = 0; j < n_reloads; j++) 3917 { 3918 if (rld[j].opnum == i) 3919 { 3920 if (rld[j].when_needed == RELOAD_FOR_OUTPUT_ADDRESS) 3921 rld[j].when_needed = RELOAD_FOR_INPUT_ADDRESS; 3922 else if (rld[j].when_needed 3923 == RELOAD_FOR_OUTADDR_ADDRESS) 3924 rld[j].when_needed = RELOAD_FOR_INPADDR_ADDRESS; 3925 } 3926 } 3927 } 3928 } 3929 else if (goal_alternative_matched[i] == -1) 3930 { 3931 operand_reloadnum[i] 3932 = push_reload ((modified[i] != RELOAD_WRITE 3933 ? recog_data.operand[i] : 0), 3934 (modified[i] != RELOAD_READ 3935 ? recog_data.operand[i] : 0), 3936 (modified[i] != RELOAD_WRITE 3937 ? recog_data.operand_loc[i] : 0), 3938 (modified[i] != RELOAD_READ 3939 ? recog_data.operand_loc[i] : 0), 3940 (enum reg_class) goal_alternative[i], 3941 (modified[i] == RELOAD_WRITE 3942 ? VOIDmode : operand_mode[i]), 3943 (modified[i] == RELOAD_READ 3944 ? VOIDmode : operand_mode[i]), 3945 (insn_code_number < 0 ? 0 3946 : insn_data[insn_code_number].operand[i].strict_low), 3947 0, i, operand_type[i]); 3948 } 3949 /* In a matching pair of operands, one must be input only 3950 and the other must be output only. 3951 Pass the input operand as IN and the other as OUT. */ 3952 else if (modified[i] == RELOAD_READ 3953 && modified[goal_alternative_matched[i]] == RELOAD_WRITE) 3954 { 3955 operand_reloadnum[i] 3956 = push_reload (recog_data.operand[i], 3957 recog_data.operand[goal_alternative_matched[i]], 3958 recog_data.operand_loc[i], 3959 recog_data.operand_loc[goal_alternative_matched[i]], 3960 (enum reg_class) goal_alternative[i], 3961 operand_mode[i], 3962 operand_mode[goal_alternative_matched[i]], 3963 0, 0, i, RELOAD_OTHER); 3964 operand_reloadnum[goal_alternative_matched[i]] = output_reloadnum; 3965 } 3966 else if (modified[i] == RELOAD_WRITE 3967 && modified[goal_alternative_matched[i]] == RELOAD_READ) 3968 { 3969 operand_reloadnum[goal_alternative_matched[i]] 3970 = push_reload (recog_data.operand[goal_alternative_matched[i]], 3971 recog_data.operand[i], 3972 recog_data.operand_loc[goal_alternative_matched[i]], 3973 recog_data.operand_loc[i], 3974 (enum reg_class) goal_alternative[i], 3975 operand_mode[goal_alternative_matched[i]], 3976 operand_mode[i], 3977 0, 0, i, RELOAD_OTHER); 3978 operand_reloadnum[i] = output_reloadnum; 3979 } 3980 else 3981 { 3982 gcc_assert (insn_code_number < 0); 3983 error_for_asm (insn, "inconsistent operand constraints " 3984 "in an %<asm%>"); 3985 /* Avoid further trouble with this insn. */ 3986 PATTERN (insn) = gen_rtx_USE (VOIDmode, const0_rtx); 3987 n_reloads = 0; 3988 return 0; 3989 } 3990 } 3991 else if (goal_alternative_matched[i] < 0 3992 && goal_alternative_matches[i] < 0 3993 && address_operand_reloaded[i] != 1 3994 && optimize) 3995 { 3996 /* For each non-matching operand that's a MEM or a pseudo-register 3997 that didn't get a hard register, make an optional reload. 3998 This may get done even if the insn needs no reloads otherwise. */ 3999 4000 rtx operand = recog_data.operand[i]; 4001 4002 while (GET_CODE (operand) == SUBREG) 4003 operand = SUBREG_REG (operand); 4004 if ((MEM_P (operand) 4005 || (REG_P (operand) 4006 && REGNO (operand) >= FIRST_PSEUDO_REGISTER)) 4007 /* If this is only for an output, the optional reload would not 4008 actually cause us to use a register now, just note that 4009 something is stored here. */ 4010 && ((enum reg_class) goal_alternative[i] != NO_REGS 4011 || modified[i] == RELOAD_WRITE) 4012 && ! no_input_reloads 4013 /* An optional output reload might allow to delete INSN later. 4014 We mustn't make in-out reloads on insns that are not permitted 4015 output reloads. 4016 If this is an asm, we can't delete it; we must not even call 4017 push_reload for an optional output reload in this case, 4018 because we can't be sure that the constraint allows a register, 4019 and push_reload verifies the constraints for asms. */ 4020 && (modified[i] == RELOAD_READ 4021 || (! no_output_reloads && ! this_insn_is_asm))) 4022 operand_reloadnum[i] 4023 = push_reload ((modified[i] != RELOAD_WRITE 4024 ? recog_data.operand[i] : 0), 4025 (modified[i] != RELOAD_READ 4026 ? recog_data.operand[i] : 0), 4027 (modified[i] != RELOAD_WRITE 4028 ? recog_data.operand_loc[i] : 0), 4029 (modified[i] != RELOAD_READ 4030 ? recog_data.operand_loc[i] : 0), 4031 (enum reg_class) goal_alternative[i], 4032 (modified[i] == RELOAD_WRITE 4033 ? VOIDmode : operand_mode[i]), 4034 (modified[i] == RELOAD_READ 4035 ? VOIDmode : operand_mode[i]), 4036 (insn_code_number < 0 ? 0 4037 : insn_data[insn_code_number].operand[i].strict_low), 4038 1, i, operand_type[i]); 4039 /* If a memory reference remains (either as a MEM or a pseudo that 4040 did not get a hard register), yet we can't make an optional 4041 reload, check if this is actually a pseudo register reference; 4042 we then need to emit a USE and/or a CLOBBER so that reload 4043 inheritance will do the right thing. */ 4044 else if (replace 4045 && (MEM_P (operand) 4046 || (REG_P (operand) 4047 && REGNO (operand) >= FIRST_PSEUDO_REGISTER 4048 && reg_renumber [REGNO (operand)] < 0))) 4049 { 4050 operand = *recog_data.operand_loc[i]; 4051 4052 while (GET_CODE (operand) == SUBREG) 4053 operand = SUBREG_REG (operand); 4054 if (REG_P (operand)) 4055 { 4056 if (modified[i] != RELOAD_WRITE) 4057 /* We mark the USE with QImode so that we recognize 4058 it as one that can be safely deleted at the end 4059 of reload. */ 4060 PUT_MODE (emit_insn_before (gen_rtx_USE (VOIDmode, operand), 4061 insn), QImode); 4062 if (modified[i] != RELOAD_READ) 4063 emit_insn_after (gen_rtx_CLOBBER (VOIDmode, operand), insn); 4064 } 4065 } 4066 } 4067 else if (goal_alternative_matches[i] >= 0 4068 && goal_alternative_win[goal_alternative_matches[i]] 4069 && modified[i] == RELOAD_READ 4070 && modified[goal_alternative_matches[i]] == RELOAD_WRITE 4071 && ! no_input_reloads && ! no_output_reloads 4072 && optimize) 4073 { 4074 /* Similarly, make an optional reload for a pair of matching 4075 objects that are in MEM or a pseudo that didn't get a hard reg. */ 4076 4077 rtx operand = recog_data.operand[i]; 4078 4079 while (GET_CODE (operand) == SUBREG) 4080 operand = SUBREG_REG (operand); 4081 if ((MEM_P (operand) 4082 || (REG_P (operand) 4083 && REGNO (operand) >= FIRST_PSEUDO_REGISTER)) 4084 && ((enum reg_class) goal_alternative[goal_alternative_matches[i]] 4085 != NO_REGS)) 4086 operand_reloadnum[i] = operand_reloadnum[goal_alternative_matches[i]] 4087 = push_reload (recog_data.operand[goal_alternative_matches[i]], 4088 recog_data.operand[i], 4089 recog_data.operand_loc[goal_alternative_matches[i]], 4090 recog_data.operand_loc[i], 4091 (enum reg_class) goal_alternative[goal_alternative_matches[i]], 4092 operand_mode[goal_alternative_matches[i]], 4093 operand_mode[i], 4094 0, 1, goal_alternative_matches[i], RELOAD_OTHER); 4095 } 4096 4097 /* Perform whatever substitutions on the operands we are supposed 4098 to make due to commutativity or replacement of registers 4099 with equivalent constants or memory slots. */ 4100 4101 for (i = 0; i < noperands; i++) 4102 { 4103 /* We only do this on the last pass through reload, because it is 4104 possible for some data (like reg_equiv_address) to be changed during 4105 later passes. Moreover, we lose the opportunity to get a useful 4106 reload_{in,out}_reg when we do these replacements. */ 4107 4108 if (replace) 4109 { 4110 rtx substitution = substed_operand[i]; 4111 4112 *recog_data.operand_loc[i] = substitution; 4113 4114 /* If we're replacing an operand with a LABEL_REF, we need 4115 to make sure that there's a REG_LABEL note attached to 4116 this instruction. */ 4117 if (!JUMP_P (insn) 4118 && GET_CODE (substitution) == LABEL_REF 4119 && !find_reg_note (insn, REG_LABEL, XEXP (substitution, 0))) 4120 REG_NOTES (insn) = gen_rtx_INSN_LIST (REG_LABEL, 4121 XEXP (substitution, 0), 4122 REG_NOTES (insn)); 4123 } 4124 else 4125 retval |= (substed_operand[i] != *recog_data.operand_loc[i]); 4126 } 4127 4128 /* If this insn pattern contains any MATCH_DUP's, make sure that 4129 they will be substituted if the operands they match are substituted. 4130 Also do now any substitutions we already did on the operands. 4131 4132 Don't do this if we aren't making replacements because we might be 4133 propagating things allocated by frame pointer elimination into places 4134 it doesn't expect. */ 4135 4136 if (insn_code_number >= 0 && replace) 4137 for (i = insn_data[insn_code_number].n_dups - 1; i >= 0; i--) 4138 { 4139 int opno = recog_data.dup_num[i]; 4140 *recog_data.dup_loc[i] = *recog_data.operand_loc[opno]; 4141 dup_replacements (recog_data.dup_loc[i], recog_data.operand_loc[opno]); 4142 } 4143 4144#if 0 4145 /* This loses because reloading of prior insns can invalidate the equivalence 4146 (or at least find_equiv_reg isn't smart enough to find it any more), 4147 causing this insn to need more reload regs than it needed before. 4148 It may be too late to make the reload regs available. 4149 Now this optimization is done safely in choose_reload_regs. */ 4150 4151 /* For each reload of a reg into some other class of reg, 4152 search for an existing equivalent reg (same value now) in the right class. 4153 We can use it as long as we don't need to change its contents. */ 4154 for (i = 0; i < n_reloads; i++) 4155 if (rld[i].reg_rtx == 0 4156 && rld[i].in != 0 4157 && REG_P (rld[i].in) 4158 && rld[i].out == 0) 4159 { 4160 rld[i].reg_rtx 4161 = find_equiv_reg (rld[i].in, insn, rld[i].class, -1, 4162 static_reload_reg_p, 0, rld[i].inmode); 4163 /* Prevent generation of insn to load the value 4164 because the one we found already has the value. */ 4165 if (rld[i].reg_rtx) 4166 rld[i].in = rld[i].reg_rtx; 4167 } 4168#endif 4169 4170 /* If we detected error and replaced asm instruction by USE, forget about the 4171 reloads. */ 4172 if (GET_CODE (PATTERN (insn)) == USE 4173 && GET_CODE (XEXP (PATTERN (insn), 0)) == CONST_INT) 4174 n_reloads = 0; 4175 4176 /* Perhaps an output reload can be combined with another 4177 to reduce needs by one. */ 4178 if (!goal_earlyclobber) 4179 combine_reloads (); 4180 4181 /* If we have a pair of reloads for parts of an address, they are reloading 4182 the same object, the operands themselves were not reloaded, and they 4183 are for two operands that are supposed to match, merge the reloads and 4184 change the type of the surviving reload to RELOAD_FOR_OPERAND_ADDRESS. */ 4185 4186 for (i = 0; i < n_reloads; i++) 4187 { 4188 int k; 4189 4190 for (j = i + 1; j < n_reloads; j++) 4191 if ((rld[i].when_needed == RELOAD_FOR_INPUT_ADDRESS 4192 || rld[i].when_needed == RELOAD_FOR_OUTPUT_ADDRESS 4193 || rld[i].when_needed == RELOAD_FOR_INPADDR_ADDRESS 4194 || rld[i].when_needed == RELOAD_FOR_OUTADDR_ADDRESS) 4195 && (rld[j].when_needed == RELOAD_FOR_INPUT_ADDRESS 4196 || rld[j].when_needed == RELOAD_FOR_OUTPUT_ADDRESS 4197 || rld[j].when_needed == RELOAD_FOR_INPADDR_ADDRESS 4198 || rld[j].when_needed == RELOAD_FOR_OUTADDR_ADDRESS) 4199 && rtx_equal_p (rld[i].in, rld[j].in) 4200 && (operand_reloadnum[rld[i].opnum] < 0 4201 || rld[operand_reloadnum[rld[i].opnum]].optional) 4202 && (operand_reloadnum[rld[j].opnum] < 0 4203 || rld[operand_reloadnum[rld[j].opnum]].optional) 4204 && (goal_alternative_matches[rld[i].opnum] == rld[j].opnum 4205 || (goal_alternative_matches[rld[j].opnum] 4206 == rld[i].opnum))) 4207 { 4208 for (k = 0; k < n_replacements; k++) 4209 if (replacements[k].what == j) 4210 replacements[k].what = i; 4211 4212 if (rld[i].when_needed == RELOAD_FOR_INPADDR_ADDRESS 4213 || rld[i].when_needed == RELOAD_FOR_OUTADDR_ADDRESS) 4214 rld[i].when_needed = RELOAD_FOR_OPADDR_ADDR; 4215 else 4216 rld[i].when_needed = RELOAD_FOR_OPERAND_ADDRESS; 4217 rld[j].in = 0; 4218 } 4219 } 4220 4221 /* Scan all the reloads and update their type. 4222 If a reload is for the address of an operand and we didn't reload 4223 that operand, change the type. Similarly, change the operand number 4224 of a reload when two operands match. If a reload is optional, treat it 4225 as though the operand isn't reloaded. 4226 4227 ??? This latter case is somewhat odd because if we do the optional 4228 reload, it means the object is hanging around. Thus we need only 4229 do the address reload if the optional reload was NOT done. 4230 4231 Change secondary reloads to be the address type of their operand, not 4232 the normal type. 4233 4234 If an operand's reload is now RELOAD_OTHER, change any 4235 RELOAD_FOR_INPUT_ADDRESS reloads of that operand to 4236 RELOAD_FOR_OTHER_ADDRESS. */ 4237 4238 for (i = 0; i < n_reloads; i++) 4239 { 4240 if (rld[i].secondary_p 4241 && rld[i].when_needed == operand_type[rld[i].opnum]) 4242 rld[i].when_needed = address_type[rld[i].opnum]; 4243 4244 if ((rld[i].when_needed == RELOAD_FOR_INPUT_ADDRESS 4245 || rld[i].when_needed == RELOAD_FOR_OUTPUT_ADDRESS 4246 || rld[i].when_needed == RELOAD_FOR_INPADDR_ADDRESS 4247 || rld[i].when_needed == RELOAD_FOR_OUTADDR_ADDRESS) 4248 && (operand_reloadnum[rld[i].opnum] < 0 4249 || rld[operand_reloadnum[rld[i].opnum]].optional)) 4250 { 4251 /* If we have a secondary reload to go along with this reload, 4252 change its type to RELOAD_FOR_OPADDR_ADDR. */ 4253 4254 if ((rld[i].when_needed == RELOAD_FOR_INPUT_ADDRESS 4255 || rld[i].when_needed == RELOAD_FOR_INPADDR_ADDRESS) 4256 && rld[i].secondary_in_reload != -1) 4257 { 4258 int secondary_in_reload = rld[i].secondary_in_reload; 4259 4260 rld[secondary_in_reload].when_needed = RELOAD_FOR_OPADDR_ADDR; 4261 4262 /* If there's a tertiary reload we have to change it also. */ 4263 if (secondary_in_reload > 0 4264 && rld[secondary_in_reload].secondary_in_reload != -1) 4265 rld[rld[secondary_in_reload].secondary_in_reload].when_needed 4266 = RELOAD_FOR_OPADDR_ADDR; 4267 } 4268 4269 if ((rld[i].when_needed == RELOAD_FOR_OUTPUT_ADDRESS 4270 || rld[i].when_needed == RELOAD_FOR_OUTADDR_ADDRESS) 4271 && rld[i].secondary_out_reload != -1) 4272 { 4273 int secondary_out_reload = rld[i].secondary_out_reload; 4274 4275 rld[secondary_out_reload].when_needed = RELOAD_FOR_OPADDR_ADDR; 4276 4277 /* If there's a tertiary reload we have to change it also. */ 4278 if (secondary_out_reload 4279 && rld[secondary_out_reload].secondary_out_reload != -1) 4280 rld[rld[secondary_out_reload].secondary_out_reload].when_needed 4281 = RELOAD_FOR_OPADDR_ADDR; 4282 } 4283 4284 if (rld[i].when_needed == RELOAD_FOR_INPADDR_ADDRESS 4285 || rld[i].when_needed == RELOAD_FOR_OUTADDR_ADDRESS) 4286 rld[i].when_needed = RELOAD_FOR_OPADDR_ADDR; 4287 else 4288 rld[i].when_needed = RELOAD_FOR_OPERAND_ADDRESS; 4289 } 4290 4291 if ((rld[i].when_needed == RELOAD_FOR_INPUT_ADDRESS 4292 || rld[i].when_needed == RELOAD_FOR_INPADDR_ADDRESS) 4293 && operand_reloadnum[rld[i].opnum] >= 0 4294 && (rld[operand_reloadnum[rld[i].opnum]].when_needed 4295 == RELOAD_OTHER)) 4296 rld[i].when_needed = RELOAD_FOR_OTHER_ADDRESS; 4297 4298 if (goal_alternative_matches[rld[i].opnum] >= 0) 4299 rld[i].opnum = goal_alternative_matches[rld[i].opnum]; 4300 } 4301 4302 /* Scan all the reloads, and check for RELOAD_FOR_OPERAND_ADDRESS reloads. 4303 If we have more than one, then convert all RELOAD_FOR_OPADDR_ADDR 4304 reloads to RELOAD_FOR_OPERAND_ADDRESS reloads. 4305 4306 choose_reload_regs assumes that RELOAD_FOR_OPADDR_ADDR reloads never 4307 conflict with RELOAD_FOR_OPERAND_ADDRESS reloads. This is true for a 4308 single pair of RELOAD_FOR_OPADDR_ADDR/RELOAD_FOR_OPERAND_ADDRESS reloads. 4309 However, if there is more than one RELOAD_FOR_OPERAND_ADDRESS reload, 4310 then a RELOAD_FOR_OPADDR_ADDR reload conflicts with all 4311 RELOAD_FOR_OPERAND_ADDRESS reloads other than the one that uses it. 4312 This is complicated by the fact that a single operand can have more 4313 than one RELOAD_FOR_OPERAND_ADDRESS reload. It is very difficult to fix 4314 choose_reload_regs without affecting code quality, and cases that 4315 actually fail are extremely rare, so it turns out to be better to fix 4316 the problem here by not generating cases that choose_reload_regs will 4317 fail for. */ 4318 /* There is a similar problem with RELOAD_FOR_INPUT_ADDRESS / 4319 RELOAD_FOR_OUTPUT_ADDRESS when there is more than one of a kind for 4320 a single operand. 4321 We can reduce the register pressure by exploiting that a 4322 RELOAD_FOR_X_ADDR_ADDR that precedes all RELOAD_FOR_X_ADDRESS reloads 4323 does not conflict with any of them, if it is only used for the first of 4324 the RELOAD_FOR_X_ADDRESS reloads. */ 4325 { 4326 int first_op_addr_num = -2; 4327 int first_inpaddr_num[MAX_RECOG_OPERANDS]; 4328 int first_outpaddr_num[MAX_RECOG_OPERANDS]; 4329 int need_change = 0; 4330 /* We use last_op_addr_reload and the contents of the above arrays 4331 first as flags - -2 means no instance encountered, -1 means exactly 4332 one instance encountered. 4333 If more than one instance has been encountered, we store the reload 4334 number of the first reload of the kind in question; reload numbers 4335 are known to be non-negative. */ 4336 for (i = 0; i < noperands; i++) 4337 first_inpaddr_num[i] = first_outpaddr_num[i] = -2; 4338 for (i = n_reloads - 1; i >= 0; i--) 4339 { 4340 switch (rld[i].when_needed) 4341 { 4342 case RELOAD_FOR_OPERAND_ADDRESS: 4343 if (++first_op_addr_num >= 0) 4344 { 4345 first_op_addr_num = i; 4346 need_change = 1; 4347 } 4348 break; 4349 case RELOAD_FOR_INPUT_ADDRESS: 4350 if (++first_inpaddr_num[rld[i].opnum] >= 0) 4351 { 4352 first_inpaddr_num[rld[i].opnum] = i; 4353 need_change = 1; 4354 } 4355 break; 4356 case RELOAD_FOR_OUTPUT_ADDRESS: 4357 if (++first_outpaddr_num[rld[i].opnum] >= 0) 4358 { 4359 first_outpaddr_num[rld[i].opnum] = i; 4360 need_change = 1; 4361 } 4362 break; 4363 default: 4364 break; 4365 } 4366 } 4367 4368 if (need_change) 4369 { 4370 for (i = 0; i < n_reloads; i++) 4371 { 4372 int first_num; 4373 enum reload_type type; 4374 4375 switch (rld[i].when_needed) 4376 { 4377 case RELOAD_FOR_OPADDR_ADDR: 4378 first_num = first_op_addr_num; 4379 type = RELOAD_FOR_OPERAND_ADDRESS; 4380 break; 4381 case RELOAD_FOR_INPADDR_ADDRESS: 4382 first_num = first_inpaddr_num[rld[i].opnum]; 4383 type = RELOAD_FOR_INPUT_ADDRESS; 4384 break; 4385 case RELOAD_FOR_OUTADDR_ADDRESS: 4386 first_num = first_outpaddr_num[rld[i].opnum]; 4387 type = RELOAD_FOR_OUTPUT_ADDRESS; 4388 break; 4389 default: 4390 continue; 4391 } 4392 if (first_num < 0) 4393 continue; 4394 else if (i > first_num) 4395 rld[i].when_needed = type; 4396 else 4397 { 4398 /* Check if the only TYPE reload that uses reload I is 4399 reload FIRST_NUM. */ 4400 for (j = n_reloads - 1; j > first_num; j--) 4401 { 4402 if (rld[j].when_needed == type 4403 && (rld[i].secondary_p 4404 ? rld[j].secondary_in_reload == i 4405 : reg_mentioned_p (rld[i].in, rld[j].in))) 4406 { 4407 rld[i].when_needed = type; 4408 break; 4409 } 4410 } 4411 } 4412 } 4413 } 4414 } 4415 4416 /* See if we have any reloads that are now allowed to be merged 4417 because we've changed when the reload is needed to 4418 RELOAD_FOR_OPERAND_ADDRESS or RELOAD_FOR_OTHER_ADDRESS. Only 4419 check for the most common cases. */ 4420 4421 for (i = 0; i < n_reloads; i++) 4422 if (rld[i].in != 0 && rld[i].out == 0 4423 && (rld[i].when_needed == RELOAD_FOR_OPERAND_ADDRESS 4424 || rld[i].when_needed == RELOAD_FOR_OPADDR_ADDR 4425 || rld[i].when_needed == RELOAD_FOR_OTHER_ADDRESS)) 4426 for (j = 0; j < n_reloads; j++) 4427 if (i != j && rld[j].in != 0 && rld[j].out == 0 4428 && rld[j].when_needed == rld[i].when_needed 4429 && MATCHES (rld[i].in, rld[j].in) 4430 && rld[i].class == rld[j].class 4431 && !rld[i].nocombine && !rld[j].nocombine 4432 && rld[i].reg_rtx == rld[j].reg_rtx) 4433 { 4434 rld[i].opnum = MIN (rld[i].opnum, rld[j].opnum); 4435 transfer_replacements (i, j); 4436 rld[j].in = 0; 4437 } 4438 4439#ifdef HAVE_cc0 4440 /* If we made any reloads for addresses, see if they violate a 4441 "no input reloads" requirement for this insn. But loads that we 4442 do after the insn (such as for output addresses) are fine. */ 4443 if (no_input_reloads) 4444 for (i = 0; i < n_reloads; i++) 4445 gcc_assert (rld[i].in == 0 4446 || rld[i].when_needed == RELOAD_FOR_OUTADDR_ADDRESS 4447 || rld[i].when_needed == RELOAD_FOR_OUTPUT_ADDRESS); 4448#endif 4449 4450 /* Compute reload_mode and reload_nregs. */ 4451 for (i = 0; i < n_reloads; i++) 4452 { 4453 rld[i].mode 4454 = (rld[i].inmode == VOIDmode 4455 || (GET_MODE_SIZE (rld[i].outmode) 4456 > GET_MODE_SIZE (rld[i].inmode))) 4457 ? rld[i].outmode : rld[i].inmode; 4458 4459 rld[i].nregs = CLASS_MAX_NREGS (rld[i].class, rld[i].mode); 4460 } 4461 4462 /* Special case a simple move with an input reload and a 4463 destination of a hard reg, if the hard reg is ok, use it. */ 4464 for (i = 0; i < n_reloads; i++) 4465 if (rld[i].when_needed == RELOAD_FOR_INPUT 4466 && GET_CODE (PATTERN (insn)) == SET 4467 && REG_P (SET_DEST (PATTERN (insn))) 4468 && SET_SRC (PATTERN (insn)) == rld[i].in) 4469 { 4470 rtx dest = SET_DEST (PATTERN (insn)); 4471 unsigned int regno = REGNO (dest); 4472 4473 if (regno < FIRST_PSEUDO_REGISTER 4474 && TEST_HARD_REG_BIT (reg_class_contents[rld[i].class], regno) 4475 && HARD_REGNO_MODE_OK (regno, rld[i].mode)) 4476 { 4477 int nr = hard_regno_nregs[regno][rld[i].mode]; 4478 int ok = 1, nri; 4479 4480 for (nri = 1; nri < nr; nri ++) 4481 if (! TEST_HARD_REG_BIT (reg_class_contents[rld[i].class], regno + nri)) 4482 ok = 0; 4483 4484 if (ok) 4485 rld[i].reg_rtx = dest; 4486 } 4487 } 4488 4489 return retval; 4490} 4491 4492/* Return 1 if alternative number ALTNUM in constraint-string CONSTRAINT 4493 accepts a memory operand with constant address. */ 4494 4495static int 4496alternative_allows_memconst (const char *constraint, int altnum) 4497{ 4498 int c; 4499 /* Skip alternatives before the one requested. */ 4500 while (altnum > 0) 4501 { 4502 while (*constraint++ != ','); 4503 altnum--; 4504 } 4505 /* Scan the requested alternative for 'm' or 'o'. 4506 If one of them is present, this alternative accepts memory constants. */ 4507 for (; (c = *constraint) && c != ',' && c != '#'; 4508 constraint += CONSTRAINT_LEN (c, constraint)) 4509 if (c == 'm' || c == 'o' || EXTRA_MEMORY_CONSTRAINT (c, constraint)) 4510 return 1; 4511 return 0; 4512} 4513 4514/* Scan X for memory references and scan the addresses for reloading. 4515 Also checks for references to "constant" regs that we want to eliminate 4516 and replaces them with the values they stand for. 4517 We may alter X destructively if it contains a reference to such. 4518 If X is just a constant reg, we return the equivalent value 4519 instead of X. 4520 4521 IND_LEVELS says how many levels of indirect addressing this machine 4522 supports. 4523 4524 OPNUM and TYPE identify the purpose of the reload. 4525 4526 IS_SET_DEST is true if X is the destination of a SET, which is not 4527 appropriate to be replaced by a constant. 4528 4529 INSN, if nonzero, is the insn in which we do the reload. It is used 4530 to determine if we may generate output reloads, and where to put USEs 4531 for pseudos that we have to replace with stack slots. 4532 4533 ADDRESS_RELOADED. If nonzero, is a pointer to where we put the 4534 result of find_reloads_address. */ 4535 4536static rtx 4537find_reloads_toplev (rtx x, int opnum, enum reload_type type, 4538 int ind_levels, int is_set_dest, rtx insn, 4539 int *address_reloaded) 4540{ 4541 RTX_CODE code = GET_CODE (x); 4542 4543 const char *fmt = GET_RTX_FORMAT (code); 4544 int i; 4545 int copied; 4546 4547 if (code == REG) 4548 { 4549 /* This code is duplicated for speed in find_reloads. */ 4550 int regno = REGNO (x); 4551 if (reg_equiv_constant[regno] != 0 && !is_set_dest) 4552 x = reg_equiv_constant[regno]; 4553#if 0 4554 /* This creates (subreg (mem...)) which would cause an unnecessary 4555 reload of the mem. */ 4556 else if (reg_equiv_mem[regno] != 0) 4557 x = reg_equiv_mem[regno]; 4558#endif 4559 else if (reg_equiv_memory_loc[regno] 4560 && (reg_equiv_address[regno] != 0 || num_not_at_initial_offset)) 4561 { 4562 rtx mem = make_memloc (x, regno); 4563 if (reg_equiv_address[regno] 4564 || ! rtx_equal_p (mem, reg_equiv_mem[regno])) 4565 { 4566 /* If this is not a toplevel operand, find_reloads doesn't see 4567 this substitution. We have to emit a USE of the pseudo so 4568 that delete_output_reload can see it. */ 4569 if (replace_reloads && recog_data.operand[opnum] != x) 4570 /* We mark the USE with QImode so that we recognize it 4571 as one that can be safely deleted at the end of 4572 reload. */ 4573 PUT_MODE (emit_insn_before (gen_rtx_USE (VOIDmode, x), insn), 4574 QImode); 4575 x = mem; 4576 i = find_reloads_address (GET_MODE (x), &x, XEXP (x, 0), &XEXP (x, 0), 4577 opnum, type, ind_levels, insn); 4578 if (x != mem) 4579 push_reg_equiv_alt_mem (regno, x); 4580 if (address_reloaded) 4581 *address_reloaded = i; 4582 } 4583 } 4584 return x; 4585 } 4586 if (code == MEM) 4587 { 4588 rtx tem = x; 4589 4590 i = find_reloads_address (GET_MODE (x), &tem, XEXP (x, 0), &XEXP (x, 0), 4591 opnum, type, ind_levels, insn); 4592 if (address_reloaded) 4593 *address_reloaded = i; 4594 4595 return tem; 4596 } 4597 4598 if (code == SUBREG && REG_P (SUBREG_REG (x))) 4599 { 4600 /* Check for SUBREG containing a REG that's equivalent to a 4601 constant. If the constant has a known value, truncate it 4602 right now. Similarly if we are extracting a single-word of a 4603 multi-word constant. If the constant is symbolic, allow it 4604 to be substituted normally. push_reload will strip the 4605 subreg later. The constant must not be VOIDmode, because we 4606 will lose the mode of the register (this should never happen 4607 because one of the cases above should handle it). */ 4608 4609 int regno = REGNO (SUBREG_REG (x)); 4610 rtx tem; 4611 4612 if (subreg_lowpart_p (x) 4613 && regno >= FIRST_PSEUDO_REGISTER 4614 && reg_renumber[regno] < 0 4615 && reg_equiv_constant[regno] != 0 4616 && (tem = gen_lowpart_common (GET_MODE (x), 4617 reg_equiv_constant[regno])) != 0) 4618 return tem; 4619 4620 if (regno >= FIRST_PSEUDO_REGISTER 4621 && reg_renumber[regno] < 0 4622 && reg_equiv_constant[regno] != 0) 4623 { 4624 tem = 4625 simplify_gen_subreg (GET_MODE (x), reg_equiv_constant[regno], 4626 GET_MODE (SUBREG_REG (x)), SUBREG_BYTE (x)); 4627 gcc_assert (tem); 4628 return tem; 4629 } 4630 4631 /* If the subreg contains a reg that will be converted to a mem, 4632 convert the subreg to a narrower memref now. 4633 Otherwise, we would get (subreg (mem ...) ...), 4634 which would force reload of the mem. 4635 4636 We also need to do this if there is an equivalent MEM that is 4637 not offsettable. In that case, alter_subreg would produce an 4638 invalid address on big-endian machines. 4639 4640 For machines that extend byte loads, we must not reload using 4641 a wider mode if we have a paradoxical SUBREG. find_reloads will 4642 force a reload in that case. So we should not do anything here. */ 4643 4644 if (regno >= FIRST_PSEUDO_REGISTER 4645#ifdef LOAD_EXTEND_OP 4646 && (GET_MODE_SIZE (GET_MODE (x)) 4647 <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))) 4648#endif 4649 && (reg_equiv_address[regno] != 0 4650 || (reg_equiv_mem[regno] != 0 4651 && (! strict_memory_address_p (GET_MODE (x), 4652 XEXP (reg_equiv_mem[regno], 0)) 4653 || ! offsettable_memref_p (reg_equiv_mem[regno]) 4654 || num_not_at_initial_offset)))) 4655 x = find_reloads_subreg_address (x, 1, opnum, type, ind_levels, 4656 insn); 4657 } 4658 4659 for (copied = 0, i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 4660 { 4661 if (fmt[i] == 'e') 4662 { 4663 rtx new_part = find_reloads_toplev (XEXP (x, i), opnum, type, 4664 ind_levels, is_set_dest, insn, 4665 address_reloaded); 4666 /* If we have replaced a reg with it's equivalent memory loc - 4667 that can still be handled here e.g. if it's in a paradoxical 4668 subreg - we must make the change in a copy, rather than using 4669 a destructive change. This way, find_reloads can still elect 4670 not to do the change. */ 4671 if (new_part != XEXP (x, i) && ! CONSTANT_P (new_part) && ! copied) 4672 { 4673 x = shallow_copy_rtx (x); 4674 copied = 1; 4675 } 4676 XEXP (x, i) = new_part; 4677 } 4678 } 4679 return x; 4680} 4681 4682/* Return a mem ref for the memory equivalent of reg REGNO. 4683 This mem ref is not shared with anything. */ 4684 4685static rtx 4686make_memloc (rtx ad, int regno) 4687{ 4688 /* We must rerun eliminate_regs, in case the elimination 4689 offsets have changed. */ 4690 rtx tem 4691 = XEXP (eliminate_regs (reg_equiv_memory_loc[regno], 0, NULL_RTX), 0); 4692 4693 /* If TEM might contain a pseudo, we must copy it to avoid 4694 modifying it when we do the substitution for the reload. */ 4695 if (rtx_varies_p (tem, 0)) 4696 tem = copy_rtx (tem); 4697 4698 tem = replace_equiv_address_nv (reg_equiv_memory_loc[regno], tem); 4699 tem = adjust_address_nv (tem, GET_MODE (ad), 0); 4700 4701 /* Copy the result if it's still the same as the equivalence, to avoid 4702 modifying it when we do the substitution for the reload. */ 4703 if (tem == reg_equiv_memory_loc[regno]) 4704 tem = copy_rtx (tem); 4705 return tem; 4706} 4707 4708/* Returns true if AD could be turned into a valid memory reference 4709 to mode MODE by reloading the part pointed to by PART into a 4710 register. */ 4711 4712static int 4713maybe_memory_address_p (enum machine_mode mode, rtx ad, rtx *part) 4714{ 4715 int retv; 4716 rtx tem = *part; 4717 rtx reg = gen_rtx_REG (GET_MODE (tem), max_reg_num ()); 4718 4719 *part = reg; 4720 retv = memory_address_p (mode, ad); 4721 *part = tem; 4722 4723 return retv; 4724} 4725 4726/* Record all reloads needed for handling memory address AD 4727 which appears in *LOC in a memory reference to mode MODE 4728 which itself is found in location *MEMREFLOC. 4729 Note that we take shortcuts assuming that no multi-reg machine mode 4730 occurs as part of an address. 4731 4732 OPNUM and TYPE specify the purpose of this reload. 4733 4734 IND_LEVELS says how many levels of indirect addressing this machine 4735 supports. 4736 4737 INSN, if nonzero, is the insn in which we do the reload. It is used 4738 to determine if we may generate output reloads, and where to put USEs 4739 for pseudos that we have to replace with stack slots. 4740 4741 Value is one if this address is reloaded or replaced as a whole; it is 4742 zero if the top level of this address was not reloaded or replaced, and 4743 it is -1 if it may or may not have been reloaded or replaced. 4744 4745 Note that there is no verification that the address will be valid after 4746 this routine does its work. Instead, we rely on the fact that the address 4747 was valid when reload started. So we need only undo things that reload 4748 could have broken. These are wrong register types, pseudos not allocated 4749 to a hard register, and frame pointer elimination. */ 4750 4751static int 4752find_reloads_address (enum machine_mode mode, rtx *memrefloc, rtx ad, 4753 rtx *loc, int opnum, enum reload_type type, 4754 int ind_levels, rtx insn) 4755{ 4756 int regno; 4757 int removed_and = 0; 4758 int op_index; 4759 rtx tem; 4760 4761 /* If the address is a register, see if it is a legitimate address and 4762 reload if not. We first handle the cases where we need not reload 4763 or where we must reload in a non-standard way. */ 4764 4765 if (REG_P (ad)) 4766 { 4767 regno = REGNO (ad); 4768 4769 /* If the register is equivalent to an invariant expression, substitute 4770 the invariant, and eliminate any eliminable register references. */ 4771 tem = reg_equiv_constant[regno]; 4772 if (tem != 0 4773 && (tem = eliminate_regs (tem, mode, insn)) 4774 && strict_memory_address_p (mode, tem)) 4775 { 4776 *loc = ad = tem; 4777 return 0; 4778 } 4779 4780 tem = reg_equiv_memory_loc[regno]; 4781 if (tem != 0) 4782 { 4783 if (reg_equiv_address[regno] != 0 || num_not_at_initial_offset) 4784 { 4785 tem = make_memloc (ad, regno); 4786 if (! strict_memory_address_p (GET_MODE (tem), XEXP (tem, 0))) 4787 { 4788 rtx orig = tem; 4789 4790 find_reloads_address (GET_MODE (tem), &tem, XEXP (tem, 0), 4791 &XEXP (tem, 0), opnum, 4792 ADDR_TYPE (type), ind_levels, insn); 4793 if (tem != orig) 4794 push_reg_equiv_alt_mem (regno, tem); 4795 } 4796 /* We can avoid a reload if the register's equivalent memory 4797 expression is valid as an indirect memory address. 4798 But not all addresses are valid in a mem used as an indirect 4799 address: only reg or reg+constant. */ 4800 4801 if (ind_levels > 0 4802 && strict_memory_address_p (mode, tem) 4803 && (REG_P (XEXP (tem, 0)) 4804 || (GET_CODE (XEXP (tem, 0)) == PLUS 4805 && REG_P (XEXP (XEXP (tem, 0), 0)) 4806 && CONSTANT_P (XEXP (XEXP (tem, 0), 1))))) 4807 { 4808 /* TEM is not the same as what we'll be replacing the 4809 pseudo with after reload, put a USE in front of INSN 4810 in the final reload pass. */ 4811 if (replace_reloads 4812 && num_not_at_initial_offset 4813 && ! rtx_equal_p (tem, reg_equiv_mem[regno])) 4814 { 4815 *loc = tem; 4816 /* We mark the USE with QImode so that we 4817 recognize it as one that can be safely 4818 deleted at the end of reload. */ 4819 PUT_MODE (emit_insn_before (gen_rtx_USE (VOIDmode, ad), 4820 insn), QImode); 4821 4822 /* This doesn't really count as replacing the address 4823 as a whole, since it is still a memory access. */ 4824 } 4825 return 0; 4826 } 4827 ad = tem; 4828 } 4829 } 4830 4831 /* The only remaining case where we can avoid a reload is if this is a 4832 hard register that is valid as a base register and which is not the 4833 subject of a CLOBBER in this insn. */ 4834 4835 else if (regno < FIRST_PSEUDO_REGISTER 4836 && regno_ok_for_base_p (regno, mode, MEM, SCRATCH) 4837 && ! regno_clobbered_p (regno, this_insn, mode, 0)) 4838 return 0; 4839 4840 /* If we do not have one of the cases above, we must do the reload. */ 4841 push_reload (ad, NULL_RTX, loc, (rtx*) 0, base_reg_class (mode, MEM, SCRATCH), 4842 GET_MODE (ad), VOIDmode, 0, 0, opnum, type); 4843 return 1; 4844 } 4845 4846 if (strict_memory_address_p (mode, ad)) 4847 { 4848 /* The address appears valid, so reloads are not needed. 4849 But the address may contain an eliminable register. 4850 This can happen because a machine with indirect addressing 4851 may consider a pseudo register by itself a valid address even when 4852 it has failed to get a hard reg. 4853 So do a tree-walk to find and eliminate all such regs. */ 4854 4855 /* But first quickly dispose of a common case. */ 4856 if (GET_CODE (ad) == PLUS 4857 && GET_CODE (XEXP (ad, 1)) == CONST_INT 4858 && REG_P (XEXP (ad, 0)) 4859 && reg_equiv_constant[REGNO (XEXP (ad, 0))] == 0) 4860 return 0; 4861 4862 subst_reg_equivs_changed = 0; 4863 *loc = subst_reg_equivs (ad, insn); 4864 4865 if (! subst_reg_equivs_changed) 4866 return 0; 4867 4868 /* Check result for validity after substitution. */ 4869 if (strict_memory_address_p (mode, ad)) 4870 return 0; 4871 } 4872 4873#ifdef LEGITIMIZE_RELOAD_ADDRESS 4874 do 4875 { 4876 if (memrefloc) 4877 { 4878 LEGITIMIZE_RELOAD_ADDRESS (ad, GET_MODE (*memrefloc), opnum, type, 4879 ind_levels, win); 4880 } 4881 break; 4882 win: 4883 *memrefloc = copy_rtx (*memrefloc); 4884 XEXP (*memrefloc, 0) = ad; 4885 move_replacements (&ad, &XEXP (*memrefloc, 0)); 4886 return -1; 4887 } 4888 while (0); 4889#endif 4890 4891 /* The address is not valid. We have to figure out why. First see if 4892 we have an outer AND and remove it if so. Then analyze what's inside. */ 4893 4894 if (GET_CODE (ad) == AND) 4895 { 4896 removed_and = 1; 4897 loc = &XEXP (ad, 0); 4898 ad = *loc; 4899 } 4900 4901 /* One possibility for why the address is invalid is that it is itself 4902 a MEM. This can happen when the frame pointer is being eliminated, a 4903 pseudo is not allocated to a hard register, and the offset between the 4904 frame and stack pointers is not its initial value. In that case the 4905 pseudo will have been replaced by a MEM referring to the 4906 stack pointer. */ 4907 if (MEM_P (ad)) 4908 { 4909 /* First ensure that the address in this MEM is valid. Then, unless 4910 indirect addresses are valid, reload the MEM into a register. */ 4911 tem = ad; 4912 find_reloads_address (GET_MODE (ad), &tem, XEXP (ad, 0), &XEXP (ad, 0), 4913 opnum, ADDR_TYPE (type), 4914 ind_levels == 0 ? 0 : ind_levels - 1, insn); 4915 4916 /* If tem was changed, then we must create a new memory reference to 4917 hold it and store it back into memrefloc. */ 4918 if (tem != ad && memrefloc) 4919 { 4920 *memrefloc = copy_rtx (*memrefloc); 4921 copy_replacements (tem, XEXP (*memrefloc, 0)); 4922 loc = &XEXP (*memrefloc, 0); 4923 if (removed_and) 4924 loc = &XEXP (*loc, 0); 4925 } 4926 4927 /* Check similar cases as for indirect addresses as above except 4928 that we can allow pseudos and a MEM since they should have been 4929 taken care of above. */ 4930 4931 if (ind_levels == 0 4932 || (GET_CODE (XEXP (tem, 0)) == SYMBOL_REF && ! indirect_symref_ok) 4933 || MEM_P (XEXP (tem, 0)) 4934 || ! (REG_P (XEXP (tem, 0)) 4935 || (GET_CODE (XEXP (tem, 0)) == PLUS 4936 && REG_P (XEXP (XEXP (tem, 0), 0)) 4937 && GET_CODE (XEXP (XEXP (tem, 0), 1)) == CONST_INT))) 4938 { 4939 /* Must use TEM here, not AD, since it is the one that will 4940 have any subexpressions reloaded, if needed. */ 4941 push_reload (tem, NULL_RTX, loc, (rtx*) 0, 4942 base_reg_class (mode, MEM, SCRATCH), GET_MODE (tem), 4943 VOIDmode, 0, 4944 0, opnum, type); 4945 return ! removed_and; 4946 } 4947 else 4948 return 0; 4949 } 4950 4951 /* If we have address of a stack slot but it's not valid because the 4952 displacement is too large, compute the sum in a register. 4953 Handle all base registers here, not just fp/ap/sp, because on some 4954 targets (namely SH) we can also get too large displacements from 4955 big-endian corrections. */ 4956 else if (GET_CODE (ad) == PLUS 4957 && REG_P (XEXP (ad, 0)) 4958 && REGNO (XEXP (ad, 0)) < FIRST_PSEUDO_REGISTER 4959 && GET_CODE (XEXP (ad, 1)) == CONST_INT 4960 && regno_ok_for_base_p (REGNO (XEXP (ad, 0)), mode, PLUS, 4961 CONST_INT)) 4962 4963 { 4964 /* Unshare the MEM rtx so we can safely alter it. */ 4965 if (memrefloc) 4966 { 4967 *memrefloc = copy_rtx (*memrefloc); 4968 loc = &XEXP (*memrefloc, 0); 4969 if (removed_and) 4970 loc = &XEXP (*loc, 0); 4971 } 4972 4973 if (double_reg_address_ok) 4974 { 4975 /* Unshare the sum as well. */ 4976 *loc = ad = copy_rtx (ad); 4977 4978 /* Reload the displacement into an index reg. 4979 We assume the frame pointer or arg pointer is a base reg. */ 4980 find_reloads_address_part (XEXP (ad, 1), &XEXP (ad, 1), 4981 INDEX_REG_CLASS, GET_MODE (ad), opnum, 4982 type, ind_levels); 4983 return 0; 4984 } 4985 else 4986 { 4987 /* If the sum of two regs is not necessarily valid, 4988 reload the sum into a base reg. 4989 That will at least work. */ 4990 find_reloads_address_part (ad, loc, 4991 base_reg_class (mode, MEM, SCRATCH), 4992 Pmode, opnum, type, ind_levels); 4993 } 4994 return ! removed_and; 4995 } 4996 4997 /* If we have an indexed stack slot, there are three possible reasons why 4998 it might be invalid: The index might need to be reloaded, the address 4999 might have been made by frame pointer elimination and hence have a 5000 constant out of range, or both reasons might apply. 5001 5002 We can easily check for an index needing reload, but even if that is the 5003 case, we might also have an invalid constant. To avoid making the 5004 conservative assumption and requiring two reloads, we see if this address 5005 is valid when not interpreted strictly. If it is, the only problem is 5006 that the index needs a reload and find_reloads_address_1 will take care 5007 of it. 5008 5009 Handle all base registers here, not just fp/ap/sp, because on some 5010 targets (namely SPARC) we can also get invalid addresses from preventive 5011 subreg big-endian corrections made by find_reloads_toplev. We 5012 can also get expressions involving LO_SUM (rather than PLUS) from 5013 find_reloads_subreg_address. 5014 5015 If we decide to do something, it must be that `double_reg_address_ok' 5016 is true. We generate a reload of the base register + constant and 5017 rework the sum so that the reload register will be added to the index. 5018 This is safe because we know the address isn't shared. 5019 5020 We check for the base register as both the first and second operand of 5021 the innermost PLUS and/or LO_SUM. */ 5022 5023 for (op_index = 0; op_index < 2; ++op_index) 5024 { 5025 rtx operand, addend; 5026 enum rtx_code inner_code; 5027 5028 if (GET_CODE (ad) != PLUS) 5029 continue; 5030 5031 inner_code = GET_CODE (XEXP (ad, 0)); 5032 if (!(GET_CODE (ad) == PLUS 5033 && GET_CODE (XEXP (ad, 1)) == CONST_INT 5034 && (inner_code == PLUS || inner_code == LO_SUM))) 5035 continue; 5036 5037 operand = XEXP (XEXP (ad, 0), op_index); 5038 if (!REG_P (operand) || REGNO (operand) >= FIRST_PSEUDO_REGISTER) 5039 continue; 5040 5041 addend = XEXP (XEXP (ad, 0), 1 - op_index); 5042 5043 if ((regno_ok_for_base_p (REGNO (operand), mode, inner_code, 5044 GET_CODE (addend)) 5045 || operand == frame_pointer_rtx 5046#if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM 5047 || operand == hard_frame_pointer_rtx 5048#endif 5049#if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM 5050 || operand == arg_pointer_rtx 5051#endif 5052 || operand == stack_pointer_rtx) 5053 && ! maybe_memory_address_p (mode, ad, 5054 &XEXP (XEXP (ad, 0), 1 - op_index))) 5055 { 5056 rtx offset_reg; 5057 enum reg_class cls; 5058 5059 offset_reg = plus_constant (operand, INTVAL (XEXP (ad, 1))); 5060 5061 /* Form the adjusted address. */ 5062 if (GET_CODE (XEXP (ad, 0)) == PLUS) 5063 ad = gen_rtx_PLUS (GET_MODE (ad), 5064 op_index == 0 ? offset_reg : addend, 5065 op_index == 0 ? addend : offset_reg); 5066 else 5067 ad = gen_rtx_LO_SUM (GET_MODE (ad), 5068 op_index == 0 ? offset_reg : addend, 5069 op_index == 0 ? addend : offset_reg); 5070 *loc = ad; 5071 5072 cls = base_reg_class (mode, MEM, GET_CODE (addend)); 5073 find_reloads_address_part (XEXP (ad, op_index), 5074 &XEXP (ad, op_index), cls, 5075 GET_MODE (ad), opnum, type, ind_levels); 5076 find_reloads_address_1 (mode, 5077 XEXP (ad, 1 - op_index), 1, GET_CODE (ad), 5078 GET_CODE (XEXP (ad, op_index)), 5079 &XEXP (ad, 1 - op_index), opnum, 5080 type, 0, insn); 5081 5082 return 0; 5083 } 5084 } 5085 5086 /* See if address becomes valid when an eliminable register 5087 in a sum is replaced. */ 5088 5089 tem = ad; 5090 if (GET_CODE (ad) == PLUS) 5091 tem = subst_indexed_address (ad); 5092 if (tem != ad && strict_memory_address_p (mode, tem)) 5093 { 5094 /* Ok, we win that way. Replace any additional eliminable 5095 registers. */ 5096 5097 subst_reg_equivs_changed = 0; 5098 tem = subst_reg_equivs (tem, insn); 5099 5100 /* Make sure that didn't make the address invalid again. */ 5101 5102 if (! subst_reg_equivs_changed || strict_memory_address_p (mode, tem)) 5103 { 5104 *loc = tem; 5105 return 0; 5106 } 5107 } 5108 5109 /* If constants aren't valid addresses, reload the constant address 5110 into a register. */ 5111 if (CONSTANT_P (ad) && ! strict_memory_address_p (mode, ad)) 5112 { 5113 /* If AD is an address in the constant pool, the MEM rtx may be shared. 5114 Unshare it so we can safely alter it. */ 5115 if (memrefloc && GET_CODE (ad) == SYMBOL_REF 5116 && CONSTANT_POOL_ADDRESS_P (ad)) 5117 { 5118 *memrefloc = copy_rtx (*memrefloc); 5119 loc = &XEXP (*memrefloc, 0); 5120 if (removed_and) 5121 loc = &XEXP (*loc, 0); 5122 } 5123 5124 find_reloads_address_part (ad, loc, base_reg_class (mode, MEM, SCRATCH), 5125 Pmode, opnum, type, ind_levels); 5126 return ! removed_and; 5127 } 5128 5129 return find_reloads_address_1 (mode, ad, 0, MEM, SCRATCH, loc, opnum, type, 5130 ind_levels, insn); 5131} 5132 5133/* Find all pseudo regs appearing in AD 5134 that are eliminable in favor of equivalent values 5135 and do not have hard regs; replace them by their equivalents. 5136 INSN, if nonzero, is the insn in which we do the reload. We put USEs in 5137 front of it for pseudos that we have to replace with stack slots. */ 5138 5139static rtx 5140subst_reg_equivs (rtx ad, rtx insn) 5141{ 5142 RTX_CODE code = GET_CODE (ad); 5143 int i; 5144 const char *fmt; 5145 5146 switch (code) 5147 { 5148 case HIGH: 5149 case CONST_INT: 5150 case CONST: 5151 case CONST_DOUBLE: 5152 case CONST_VECTOR: 5153 case SYMBOL_REF: 5154 case LABEL_REF: 5155 case PC: 5156 case CC0: 5157 return ad; 5158 5159 case REG: 5160 { 5161 int regno = REGNO (ad); 5162 5163 if (reg_equiv_constant[regno] != 0) 5164 { 5165 subst_reg_equivs_changed = 1; 5166 return reg_equiv_constant[regno]; 5167 } 5168 if (reg_equiv_memory_loc[regno] && num_not_at_initial_offset) 5169 { 5170 rtx mem = make_memloc (ad, regno); 5171 if (! rtx_equal_p (mem, reg_equiv_mem[regno])) 5172 { 5173 subst_reg_equivs_changed = 1; 5174 /* We mark the USE with QImode so that we recognize it 5175 as one that can be safely deleted at the end of 5176 reload. */ 5177 PUT_MODE (emit_insn_before (gen_rtx_USE (VOIDmode, ad), insn), 5178 QImode); 5179 return mem; 5180 } 5181 } 5182 } 5183 return ad; 5184 5185 case PLUS: 5186 /* Quickly dispose of a common case. */ 5187 if (XEXP (ad, 0) == frame_pointer_rtx 5188 && GET_CODE (XEXP (ad, 1)) == CONST_INT) 5189 return ad; 5190 break; 5191 5192 default: 5193 break; 5194 } 5195 5196 fmt = GET_RTX_FORMAT (code); 5197 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 5198 if (fmt[i] == 'e') 5199 XEXP (ad, i) = subst_reg_equivs (XEXP (ad, i), insn); 5200 return ad; 5201} 5202 5203/* Compute the sum of X and Y, making canonicalizations assumed in an 5204 address, namely: sum constant integers, surround the sum of two 5205 constants with a CONST, put the constant as the second operand, and 5206 group the constant on the outermost sum. 5207 5208 This routine assumes both inputs are already in canonical form. */ 5209 5210rtx 5211form_sum (rtx x, rtx y) 5212{ 5213 rtx tem; 5214 enum machine_mode mode = GET_MODE (x); 5215 5216 if (mode == VOIDmode) 5217 mode = GET_MODE (y); 5218 5219 if (mode == VOIDmode) 5220 mode = Pmode; 5221 5222 if (GET_CODE (x) == CONST_INT) 5223 return plus_constant (y, INTVAL (x)); 5224 else if (GET_CODE (y) == CONST_INT) 5225 return plus_constant (x, INTVAL (y)); 5226 else if (CONSTANT_P (x)) 5227 tem = x, x = y, y = tem; 5228 5229 if (GET_CODE (x) == PLUS && CONSTANT_P (XEXP (x, 1))) 5230 return form_sum (XEXP (x, 0), form_sum (XEXP (x, 1), y)); 5231 5232 /* Note that if the operands of Y are specified in the opposite 5233 order in the recursive calls below, infinite recursion will occur. */ 5234 if (GET_CODE (y) == PLUS && CONSTANT_P (XEXP (y, 1))) 5235 return form_sum (form_sum (x, XEXP (y, 0)), XEXP (y, 1)); 5236 5237 /* If both constant, encapsulate sum. Otherwise, just form sum. A 5238 constant will have been placed second. */ 5239 if (CONSTANT_P (x) && CONSTANT_P (y)) 5240 { 5241 if (GET_CODE (x) == CONST) 5242 x = XEXP (x, 0); 5243 if (GET_CODE (y) == CONST) 5244 y = XEXP (y, 0); 5245 5246 return gen_rtx_CONST (VOIDmode, gen_rtx_PLUS (mode, x, y)); 5247 } 5248 5249 return gen_rtx_PLUS (mode, x, y); 5250} 5251 5252/* If ADDR is a sum containing a pseudo register that should be 5253 replaced with a constant (from reg_equiv_constant), 5254 return the result of doing so, and also apply the associative 5255 law so that the result is more likely to be a valid address. 5256 (But it is not guaranteed to be one.) 5257 5258 Note that at most one register is replaced, even if more are 5259 replaceable. Also, we try to put the result into a canonical form 5260 so it is more likely to be a valid address. 5261 5262 In all other cases, return ADDR. */ 5263 5264static rtx 5265subst_indexed_address (rtx addr) 5266{ 5267 rtx op0 = 0, op1 = 0, op2 = 0; 5268 rtx tem; 5269 int regno; 5270 5271 if (GET_CODE (addr) == PLUS) 5272 { 5273 /* Try to find a register to replace. */ 5274 op0 = XEXP (addr, 0), op1 = XEXP (addr, 1), op2 = 0; 5275 if (REG_P (op0) 5276 && (regno = REGNO (op0)) >= FIRST_PSEUDO_REGISTER 5277 && reg_renumber[regno] < 0 5278 && reg_equiv_constant[regno] != 0) 5279 op0 = reg_equiv_constant[regno]; 5280 else if (REG_P (op1) 5281 && (regno = REGNO (op1)) >= FIRST_PSEUDO_REGISTER 5282 && reg_renumber[regno] < 0 5283 && reg_equiv_constant[regno] != 0) 5284 op1 = reg_equiv_constant[regno]; 5285 else if (GET_CODE (op0) == PLUS 5286 && (tem = subst_indexed_address (op0)) != op0) 5287 op0 = tem; 5288 else if (GET_CODE (op1) == PLUS 5289 && (tem = subst_indexed_address (op1)) != op1) 5290 op1 = tem; 5291 else 5292 return addr; 5293 5294 /* Pick out up to three things to add. */ 5295 if (GET_CODE (op1) == PLUS) 5296 op2 = XEXP (op1, 1), op1 = XEXP (op1, 0); 5297 else if (GET_CODE (op0) == PLUS) 5298 op2 = op1, op1 = XEXP (op0, 1), op0 = XEXP (op0, 0); 5299 5300 /* Compute the sum. */ 5301 if (op2 != 0) 5302 op1 = form_sum (op1, op2); 5303 if (op1 != 0) 5304 op0 = form_sum (op0, op1); 5305 5306 return op0; 5307 } 5308 return addr; 5309} 5310 5311/* Update the REG_INC notes for an insn. It updates all REG_INC 5312 notes for the instruction which refer to REGNO the to refer 5313 to the reload number. 5314 5315 INSN is the insn for which any REG_INC notes need updating. 5316 5317 REGNO is the register number which has been reloaded. 5318 5319 RELOADNUM is the reload number. */ 5320 5321static void 5322update_auto_inc_notes (rtx insn ATTRIBUTE_UNUSED, int regno ATTRIBUTE_UNUSED, 5323 int reloadnum ATTRIBUTE_UNUSED) 5324{ 5325#ifdef AUTO_INC_DEC 5326 rtx link; 5327 5328 for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) 5329 if (REG_NOTE_KIND (link) == REG_INC 5330 && (int) REGNO (XEXP (link, 0)) == regno) 5331 push_replacement (&XEXP (link, 0), reloadnum, VOIDmode); 5332#endif 5333} 5334 5335/* Record the pseudo registers we must reload into hard registers in a 5336 subexpression of a would-be memory address, X referring to a value 5337 in mode MODE. (This function is not called if the address we find 5338 is strictly valid.) 5339 5340 CONTEXT = 1 means we are considering regs as index regs, 5341 = 0 means we are considering them as base regs. 5342 OUTER_CODE is the code of the enclosing RTX, typically a MEM, a PLUS, 5343 or an autoinc code. 5344 If CONTEXT == 0 and OUTER_CODE is a PLUS or LO_SUM, then INDEX_CODE 5345 is the code of the index part of the address. Otherwise, pass SCRATCH 5346 for this argument. 5347 OPNUM and TYPE specify the purpose of any reloads made. 5348 5349 IND_LEVELS says how many levels of indirect addressing are 5350 supported at this point in the address. 5351 5352 INSN, if nonzero, is the insn in which we do the reload. It is used 5353 to determine if we may generate output reloads. 5354 5355 We return nonzero if X, as a whole, is reloaded or replaced. */ 5356 5357/* Note that we take shortcuts assuming that no multi-reg machine mode 5358 occurs as part of an address. 5359 Also, this is not fully machine-customizable; it works for machines 5360 such as VAXen and 68000's and 32000's, but other possible machines 5361 could have addressing modes that this does not handle right. 5362 If you add push_reload calls here, you need to make sure gen_reload 5363 handles those cases gracefully. */ 5364 5365static int 5366find_reloads_address_1 (enum machine_mode mode, rtx x, int context, 5367 enum rtx_code outer_code, enum rtx_code index_code, 5368 rtx *loc, int opnum, enum reload_type type, 5369 int ind_levels, rtx insn) 5370{ 5371#define REG_OK_FOR_CONTEXT(CONTEXT, REGNO, MODE, OUTER, INDEX) \ 5372 ((CONTEXT) == 0 \ 5373 ? regno_ok_for_base_p (REGNO, MODE, OUTER, INDEX) \ 5374 : REGNO_OK_FOR_INDEX_P (REGNO)) 5375 5376 enum reg_class context_reg_class; 5377 RTX_CODE code = GET_CODE (x); 5378 5379 if (context == 1) 5380 context_reg_class = INDEX_REG_CLASS; 5381 else 5382 context_reg_class = base_reg_class (mode, outer_code, index_code); 5383 5384 switch (code) 5385 { 5386 case PLUS: 5387 { 5388 rtx orig_op0 = XEXP (x, 0); 5389 rtx orig_op1 = XEXP (x, 1); 5390 RTX_CODE code0 = GET_CODE (orig_op0); 5391 RTX_CODE code1 = GET_CODE (orig_op1); 5392 rtx op0 = orig_op0; 5393 rtx op1 = orig_op1; 5394 5395 if (GET_CODE (op0) == SUBREG) 5396 { 5397 op0 = SUBREG_REG (op0); 5398 code0 = GET_CODE (op0); 5399 if (code0 == REG && REGNO (op0) < FIRST_PSEUDO_REGISTER) 5400 op0 = gen_rtx_REG (word_mode, 5401 (REGNO (op0) + 5402 subreg_regno_offset (REGNO (SUBREG_REG (orig_op0)), 5403 GET_MODE (SUBREG_REG (orig_op0)), 5404 SUBREG_BYTE (orig_op0), 5405 GET_MODE (orig_op0)))); 5406 } 5407 5408 if (GET_CODE (op1) == SUBREG) 5409 { 5410 op1 = SUBREG_REG (op1); 5411 code1 = GET_CODE (op1); 5412 if (code1 == REG && REGNO (op1) < FIRST_PSEUDO_REGISTER) 5413 /* ??? Why is this given op1's mode and above for 5414 ??? op0 SUBREGs we use word_mode? */ 5415 op1 = gen_rtx_REG (GET_MODE (op1), 5416 (REGNO (op1) + 5417 subreg_regno_offset (REGNO (SUBREG_REG (orig_op1)), 5418 GET_MODE (SUBREG_REG (orig_op1)), 5419 SUBREG_BYTE (orig_op1), 5420 GET_MODE (orig_op1)))); 5421 } 5422 /* Plus in the index register may be created only as a result of 5423 register rematerialization for expression like &localvar*4. Reload it. 5424 It may be possible to combine the displacement on the outer level, 5425 but it is probably not worthwhile to do so. */ 5426 if (context == 1) 5427 { 5428 find_reloads_address (GET_MODE (x), loc, XEXP (x, 0), &XEXP (x, 0), 5429 opnum, ADDR_TYPE (type), ind_levels, insn); 5430 push_reload (*loc, NULL_RTX, loc, (rtx*) 0, 5431 context_reg_class, 5432 GET_MODE (x), VOIDmode, 0, 0, opnum, type); 5433 return 1; 5434 } 5435 5436 if (code0 == MULT || code0 == SIGN_EXTEND || code0 == TRUNCATE 5437 || code0 == ZERO_EXTEND || code1 == MEM) 5438 { 5439 find_reloads_address_1 (mode, orig_op0, 1, PLUS, SCRATCH, 5440 &XEXP (x, 0), opnum, type, ind_levels, 5441 insn); 5442 find_reloads_address_1 (mode, orig_op1, 0, PLUS, code0, 5443 &XEXP (x, 1), opnum, type, ind_levels, 5444 insn); 5445 } 5446 5447 else if (code1 == MULT || code1 == SIGN_EXTEND || code1 == TRUNCATE 5448 || code1 == ZERO_EXTEND || code0 == MEM) 5449 { 5450 find_reloads_address_1 (mode, orig_op0, 0, PLUS, code1, 5451 &XEXP (x, 0), opnum, type, ind_levels, 5452 insn); 5453 find_reloads_address_1 (mode, orig_op1, 1, PLUS, SCRATCH, 5454 &XEXP (x, 1), opnum, type, ind_levels, 5455 insn); 5456 } 5457 5458 else if (code0 == CONST_INT || code0 == CONST 5459 || code0 == SYMBOL_REF || code0 == LABEL_REF) 5460 find_reloads_address_1 (mode, orig_op1, 0, PLUS, code0, 5461 &XEXP (x, 1), opnum, type, ind_levels, 5462 insn); 5463 5464 else if (code1 == CONST_INT || code1 == CONST 5465 || code1 == SYMBOL_REF || code1 == LABEL_REF) 5466 find_reloads_address_1 (mode, orig_op0, 0, PLUS, code1, 5467 &XEXP (x, 0), opnum, type, ind_levels, 5468 insn); 5469 5470 else if (code0 == REG && code1 == REG) 5471 { 5472 if (REGNO_OK_FOR_INDEX_P (REGNO (op0)) 5473 && regno_ok_for_base_p (REGNO (op1), mode, PLUS, REG)) 5474 return 0; 5475 else if (REGNO_OK_FOR_INDEX_P (REGNO (op1)) 5476 && regno_ok_for_base_p (REGNO (op0), mode, PLUS, REG)) 5477 return 0; 5478 else if (regno_ok_for_base_p (REGNO (op1), mode, PLUS, REG)) 5479 find_reloads_address_1 (mode, orig_op0, 1, PLUS, SCRATCH, 5480 &XEXP (x, 0), opnum, type, ind_levels, 5481 insn); 5482 else if (regno_ok_for_base_p (REGNO (op0), mode, PLUS, REG)) 5483 find_reloads_address_1 (mode, orig_op1, 1, PLUS, SCRATCH, 5484 &XEXP (x, 1), opnum, type, ind_levels, 5485 insn); 5486 else if (REGNO_OK_FOR_INDEX_P (REGNO (op1))) 5487 find_reloads_address_1 (mode, orig_op0, 0, PLUS, REG, 5488 &XEXP (x, 0), opnum, type, ind_levels, 5489 insn); 5490 else if (REGNO_OK_FOR_INDEX_P (REGNO (op0))) 5491 find_reloads_address_1 (mode, orig_op1, 0, PLUS, REG, 5492 &XEXP (x, 1), opnum, type, ind_levels, 5493 insn); 5494 else 5495 { 5496 find_reloads_address_1 (mode, orig_op0, 1, PLUS, SCRATCH, 5497 &XEXP (x, 0), opnum, type, ind_levels, 5498 insn); 5499 find_reloads_address_1 (mode, orig_op1, 0, PLUS, REG, 5500 &XEXP (x, 1), opnum, type, ind_levels, 5501 insn); 5502 } 5503 } 5504 5505 else if (code0 == REG) 5506 { 5507 find_reloads_address_1 (mode, orig_op0, 1, PLUS, SCRATCH, 5508 &XEXP (x, 0), opnum, type, ind_levels, 5509 insn); 5510 find_reloads_address_1 (mode, orig_op1, 0, PLUS, REG, 5511 &XEXP (x, 1), opnum, type, ind_levels, 5512 insn); 5513 } 5514 5515 else if (code1 == REG) 5516 { 5517 find_reloads_address_1 (mode, orig_op1, 1, PLUS, SCRATCH, 5518 &XEXP (x, 1), opnum, type, ind_levels, 5519 insn); 5520 find_reloads_address_1 (mode, orig_op0, 0, PLUS, REG, 5521 &XEXP (x, 0), opnum, type, ind_levels, 5522 insn); 5523 } 5524 } 5525 5526 return 0; 5527 5528 case POST_MODIFY: 5529 case PRE_MODIFY: 5530 { 5531 rtx op0 = XEXP (x, 0); 5532 rtx op1 = XEXP (x, 1); 5533 enum rtx_code index_code; 5534 int regno; 5535 int reloadnum; 5536 5537 if (GET_CODE (op1) != PLUS && GET_CODE (op1) != MINUS) 5538 return 0; 5539 5540 /* Currently, we only support {PRE,POST}_MODIFY constructs 5541 where a base register is {inc,dec}remented by the contents 5542 of another register or by a constant value. Thus, these 5543 operands must match. */ 5544 gcc_assert (op0 == XEXP (op1, 0)); 5545 5546 /* Require index register (or constant). Let's just handle the 5547 register case in the meantime... If the target allows 5548 auto-modify by a constant then we could try replacing a pseudo 5549 register with its equivalent constant where applicable. 5550 5551 If we later decide to reload the whole PRE_MODIFY or 5552 POST_MODIFY, inc_for_reload might clobber the reload register 5553 before reading the index. The index register might therefore 5554 need to live longer than a TYPE reload normally would, so be 5555 conservative and class it as RELOAD_OTHER. */ 5556 if (REG_P (XEXP (op1, 1))) 5557 if (!REGNO_OK_FOR_INDEX_P (REGNO (XEXP (op1, 1)))) 5558 find_reloads_address_1 (mode, XEXP (op1, 1), 1, code, SCRATCH, 5559 &XEXP (op1, 1), opnum, RELOAD_OTHER, 5560 ind_levels, insn); 5561 5562 gcc_assert (REG_P (XEXP (op1, 0))); 5563 5564 regno = REGNO (XEXP (op1, 0)); 5565 index_code = GET_CODE (XEXP (op1, 1)); 5566 5567 /* A register that is incremented cannot be constant! */ 5568 gcc_assert (regno < FIRST_PSEUDO_REGISTER 5569 || reg_equiv_constant[regno] == 0); 5570 5571 /* Handle a register that is equivalent to a memory location 5572 which cannot be addressed directly. */ 5573 if (reg_equiv_memory_loc[regno] != 0 5574 && (reg_equiv_address[regno] != 0 5575 || num_not_at_initial_offset)) 5576 { 5577 rtx tem = make_memloc (XEXP (x, 0), regno); 5578 5579 if (reg_equiv_address[regno] 5580 || ! rtx_equal_p (tem, reg_equiv_mem[regno])) 5581 { 5582 rtx orig = tem; 5583 5584 /* First reload the memory location's address. 5585 We can't use ADDR_TYPE (type) here, because we need to 5586 write back the value after reading it, hence we actually 5587 need two registers. */ 5588 find_reloads_address (GET_MODE (tem), &tem, XEXP (tem, 0), 5589 &XEXP (tem, 0), opnum, 5590 RELOAD_OTHER, 5591 ind_levels, insn); 5592 5593 if (tem != orig) 5594 push_reg_equiv_alt_mem (regno, tem); 5595 5596 /* Then reload the memory location into a base 5597 register. */ 5598 reloadnum = push_reload (tem, tem, &XEXP (x, 0), 5599 &XEXP (op1, 0), 5600 base_reg_class (mode, code, 5601 index_code), 5602 GET_MODE (x), GET_MODE (x), 0, 5603 0, opnum, RELOAD_OTHER); 5604 5605 update_auto_inc_notes (this_insn, regno, reloadnum); 5606 return 0; 5607 } 5608 } 5609 5610 if (reg_renumber[regno] >= 0) 5611 regno = reg_renumber[regno]; 5612 5613 /* We require a base register here... */ 5614 if (!regno_ok_for_base_p (regno, GET_MODE (x), code, index_code)) 5615 { 5616 reloadnum = push_reload (XEXP (op1, 0), XEXP (x, 0), 5617 &XEXP (op1, 0), &XEXP (x, 0), 5618 base_reg_class (mode, code, index_code), 5619 GET_MODE (x), GET_MODE (x), 0, 0, 5620 opnum, RELOAD_OTHER); 5621 5622 update_auto_inc_notes (this_insn, regno, reloadnum); 5623 return 0; 5624 } 5625 } 5626 return 0; 5627 5628 case POST_INC: 5629 case POST_DEC: 5630 case PRE_INC: 5631 case PRE_DEC: 5632 if (REG_P (XEXP (x, 0))) 5633 { 5634 int regno = REGNO (XEXP (x, 0)); 5635 int value = 0; 5636 rtx x_orig = x; 5637 5638 /* A register that is incremented cannot be constant! */ 5639 gcc_assert (regno < FIRST_PSEUDO_REGISTER 5640 || reg_equiv_constant[regno] == 0); 5641 5642 /* Handle a register that is equivalent to a memory location 5643 which cannot be addressed directly. */ 5644 if (reg_equiv_memory_loc[regno] != 0 5645 && (reg_equiv_address[regno] != 0 || num_not_at_initial_offset)) 5646 { 5647 rtx tem = make_memloc (XEXP (x, 0), regno); 5648 if (reg_equiv_address[regno] 5649 || ! rtx_equal_p (tem, reg_equiv_mem[regno])) 5650 { 5651 rtx orig = tem; 5652 5653 /* First reload the memory location's address. 5654 We can't use ADDR_TYPE (type) here, because we need to 5655 write back the value after reading it, hence we actually 5656 need two registers. */ 5657 find_reloads_address (GET_MODE (tem), &tem, XEXP (tem, 0), 5658 &XEXP (tem, 0), opnum, type, 5659 ind_levels, insn); 5660 if (tem != orig) 5661 push_reg_equiv_alt_mem (regno, tem); 5662 /* Put this inside a new increment-expression. */ 5663 x = gen_rtx_fmt_e (GET_CODE (x), GET_MODE (x), tem); 5664 /* Proceed to reload that, as if it contained a register. */ 5665 } 5666 } 5667 5668 /* If we have a hard register that is ok as an index, 5669 don't make a reload. If an autoincrement of a nice register 5670 isn't "valid", it must be that no autoincrement is "valid". 5671 If that is true and something made an autoincrement anyway, 5672 this must be a special context where one is allowed. 5673 (For example, a "push" instruction.) 5674 We can't improve this address, so leave it alone. */ 5675 5676 /* Otherwise, reload the autoincrement into a suitable hard reg 5677 and record how much to increment by. */ 5678 5679 if (reg_renumber[regno] >= 0) 5680 regno = reg_renumber[regno]; 5681 if (regno >= FIRST_PSEUDO_REGISTER 5682 || !REG_OK_FOR_CONTEXT (context, regno, mode, outer_code, 5683 index_code)) 5684 { 5685 int reloadnum; 5686 5687 /* If we can output the register afterwards, do so, this 5688 saves the extra update. 5689 We can do so if we have an INSN - i.e. no JUMP_INSN nor 5690 CALL_INSN - and it does not set CC0. 5691 But don't do this if we cannot directly address the 5692 memory location, since this will make it harder to 5693 reuse address reloads, and increases register pressure. 5694 Also don't do this if we can probably update x directly. */ 5695 rtx equiv = (MEM_P (XEXP (x, 0)) 5696 ? XEXP (x, 0) 5697 : reg_equiv_mem[regno]); 5698 int icode = (int) add_optab->handlers[(int) Pmode].insn_code; 5699 if (insn && NONJUMP_INSN_P (insn) && equiv 5700 && memory_operand (equiv, GET_MODE (equiv)) 5701#ifdef HAVE_cc0 5702 && ! sets_cc0_p (PATTERN (insn)) 5703#endif 5704 && ! (icode != CODE_FOR_nothing 5705 && ((*insn_data[icode].operand[0].predicate) 5706 (equiv, Pmode)) 5707 && ((*insn_data[icode].operand[1].predicate) 5708 (equiv, Pmode)))) 5709 { 5710 /* We use the original pseudo for loc, so that 5711 emit_reload_insns() knows which pseudo this 5712 reload refers to and updates the pseudo rtx, not 5713 its equivalent memory location, as well as the 5714 corresponding entry in reg_last_reload_reg. */ 5715 loc = &XEXP (x_orig, 0); 5716 x = XEXP (x, 0); 5717 reloadnum 5718 = push_reload (x, x, loc, loc, 5719 context_reg_class, 5720 GET_MODE (x), GET_MODE (x), 0, 0, 5721 opnum, RELOAD_OTHER); 5722 } 5723 else 5724 { 5725 reloadnum 5726 = push_reload (x, NULL_RTX, loc, (rtx*) 0, 5727 context_reg_class, 5728 GET_MODE (x), GET_MODE (x), 0, 0, 5729 opnum, type); 5730 rld[reloadnum].inc 5731 = find_inc_amount (PATTERN (this_insn), XEXP (x_orig, 0)); 5732 5733 value = 1; 5734 } 5735 5736 update_auto_inc_notes (this_insn, REGNO (XEXP (x_orig, 0)), 5737 reloadnum); 5738 } 5739 return value; 5740 } 5741 5742 else if (MEM_P (XEXP (x, 0))) 5743 { 5744 /* This is probably the result of a substitution, by eliminate_regs, 5745 of an equivalent address for a pseudo that was not allocated to a 5746 hard register. Verify that the specified address is valid and 5747 reload it into a register. */ 5748 /* Variable `tem' might or might not be used in FIND_REG_INC_NOTE. */ 5749 rtx tem ATTRIBUTE_UNUSED = XEXP (x, 0); 5750 rtx link; 5751 int reloadnum; 5752 5753 /* Since we know we are going to reload this item, don't decrement 5754 for the indirection level. 5755 5756 Note that this is actually conservative: it would be slightly 5757 more efficient to use the value of SPILL_INDIRECT_LEVELS from 5758 reload1.c here. */ 5759 /* We can't use ADDR_TYPE (type) here, because we need to 5760 write back the value after reading it, hence we actually 5761 need two registers. */ 5762 find_reloads_address (GET_MODE (x), &XEXP (x, 0), 5763 XEXP (XEXP (x, 0), 0), &XEXP (XEXP (x, 0), 0), 5764 opnum, type, ind_levels, insn); 5765 5766 reloadnum = push_reload (x, NULL_RTX, loc, (rtx*) 0, 5767 context_reg_class, 5768 GET_MODE (x), VOIDmode, 0, 0, opnum, type); 5769 rld[reloadnum].inc 5770 = find_inc_amount (PATTERN (this_insn), XEXP (x, 0)); 5771 5772 link = FIND_REG_INC_NOTE (this_insn, tem); 5773 if (link != 0) 5774 push_replacement (&XEXP (link, 0), reloadnum, VOIDmode); 5775 5776 return 1; 5777 } 5778 return 0; 5779 5780 case TRUNCATE: 5781 case SIGN_EXTEND: 5782 case ZERO_EXTEND: 5783 /* Look for parts to reload in the inner expression and reload them 5784 too, in addition to this operation. Reloading all inner parts in 5785 addition to this one shouldn't be necessary, but at this point, 5786 we don't know if we can possibly omit any part that *can* be 5787 reloaded. Targets that are better off reloading just either part 5788 (or perhaps even a different part of an outer expression), should 5789 define LEGITIMIZE_RELOAD_ADDRESS. */ 5790 find_reloads_address_1 (GET_MODE (XEXP (x, 0)), XEXP (x, 0), 5791 context, code, SCRATCH, &XEXP (x, 0), opnum, 5792 type, ind_levels, insn); 5793 push_reload (x, NULL_RTX, loc, (rtx*) 0, 5794 context_reg_class, 5795 GET_MODE (x), VOIDmode, 0, 0, opnum, type); 5796 return 1; 5797 5798 case MEM: 5799 /* This is probably the result of a substitution, by eliminate_regs, of 5800 an equivalent address for a pseudo that was not allocated to a hard 5801 register. Verify that the specified address is valid and reload it 5802 into a register. 5803 5804 Since we know we are going to reload this item, don't decrement for 5805 the indirection level. 5806 5807 Note that this is actually conservative: it would be slightly more 5808 efficient to use the value of SPILL_INDIRECT_LEVELS from 5809 reload1.c here. */ 5810 5811 find_reloads_address (GET_MODE (x), loc, XEXP (x, 0), &XEXP (x, 0), 5812 opnum, ADDR_TYPE (type), ind_levels, insn); 5813 push_reload (*loc, NULL_RTX, loc, (rtx*) 0, 5814 context_reg_class, 5815 GET_MODE (x), VOIDmode, 0, 0, opnum, type); 5816 return 1; 5817 5818 case REG: 5819 { 5820 int regno = REGNO (x); 5821 5822 if (reg_equiv_constant[regno] != 0) 5823 { 5824 find_reloads_address_part (reg_equiv_constant[regno], loc, 5825 context_reg_class, 5826 GET_MODE (x), opnum, type, ind_levels); 5827 return 1; 5828 } 5829 5830#if 0 /* This might screw code in reload1.c to delete prior output-reload 5831 that feeds this insn. */ 5832 if (reg_equiv_mem[regno] != 0) 5833 { 5834 push_reload (reg_equiv_mem[regno], NULL_RTX, loc, (rtx*) 0, 5835 context_reg_class, 5836 GET_MODE (x), VOIDmode, 0, 0, opnum, type); 5837 return 1; 5838 } 5839#endif 5840 5841 if (reg_equiv_memory_loc[regno] 5842 && (reg_equiv_address[regno] != 0 || num_not_at_initial_offset)) 5843 { 5844 rtx tem = make_memloc (x, regno); 5845 if (reg_equiv_address[regno] != 0 5846 || ! rtx_equal_p (tem, reg_equiv_mem[regno])) 5847 { 5848 x = tem; 5849 find_reloads_address (GET_MODE (x), &x, XEXP (x, 0), 5850 &XEXP (x, 0), opnum, ADDR_TYPE (type), 5851 ind_levels, insn); 5852 if (x != tem) 5853 push_reg_equiv_alt_mem (regno, x); 5854 } 5855 } 5856 5857 if (reg_renumber[regno] >= 0) 5858 regno = reg_renumber[regno]; 5859 5860 if (regno >= FIRST_PSEUDO_REGISTER 5861 || !REG_OK_FOR_CONTEXT (context, regno, mode, outer_code, 5862 index_code)) 5863 { 5864 push_reload (x, NULL_RTX, loc, (rtx*) 0, 5865 context_reg_class, 5866 GET_MODE (x), VOIDmode, 0, 0, opnum, type); 5867 return 1; 5868 } 5869 5870 /* If a register appearing in an address is the subject of a CLOBBER 5871 in this insn, reload it into some other register to be safe. 5872 The CLOBBER is supposed to make the register unavailable 5873 from before this insn to after it. */ 5874 if (regno_clobbered_p (regno, this_insn, GET_MODE (x), 0)) 5875 { 5876 push_reload (x, NULL_RTX, loc, (rtx*) 0, 5877 context_reg_class, 5878 GET_MODE (x), VOIDmode, 0, 0, opnum, type); 5879 return 1; 5880 } 5881 } 5882 return 0; 5883 5884 case SUBREG: 5885 if (REG_P (SUBREG_REG (x))) 5886 { 5887 /* If this is a SUBREG of a hard register and the resulting register 5888 is of the wrong class, reload the whole SUBREG. This avoids 5889 needless copies if SUBREG_REG is multi-word. */ 5890 if (REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER) 5891 { 5892 int regno ATTRIBUTE_UNUSED = subreg_regno (x); 5893 5894 if (!REG_OK_FOR_CONTEXT (context, regno, mode, outer_code, 5895 index_code)) 5896 { 5897 push_reload (x, NULL_RTX, loc, (rtx*) 0, 5898 context_reg_class, 5899 GET_MODE (x), VOIDmode, 0, 0, opnum, type); 5900 return 1; 5901 } 5902 } 5903 /* If this is a SUBREG of a pseudo-register, and the pseudo-register 5904 is larger than the class size, then reload the whole SUBREG. */ 5905 else 5906 { 5907 enum reg_class class = context_reg_class; 5908 if ((unsigned) CLASS_MAX_NREGS (class, GET_MODE (SUBREG_REG (x))) 5909 > reg_class_size[class]) 5910 { 5911 x = find_reloads_subreg_address (x, 0, opnum, 5912 ADDR_TYPE (type), 5913 ind_levels, insn); 5914 push_reload (x, NULL_RTX, loc, (rtx*) 0, class, 5915 GET_MODE (x), VOIDmode, 0, 0, opnum, type); 5916 return 1; 5917 } 5918 } 5919 } 5920 break; 5921 5922 default: 5923 break; 5924 } 5925 5926 { 5927 const char *fmt = GET_RTX_FORMAT (code); 5928 int i; 5929 5930 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 5931 { 5932 if (fmt[i] == 'e') 5933 /* Pass SCRATCH for INDEX_CODE, since CODE can never be a PLUS once 5934 we get here. */ 5935 find_reloads_address_1 (mode, XEXP (x, i), context, code, SCRATCH, 5936 &XEXP (x, i), opnum, type, ind_levels, insn); 5937 } 5938 } 5939 5940#undef REG_OK_FOR_CONTEXT 5941 return 0; 5942} 5943 5944/* X, which is found at *LOC, is a part of an address that needs to be 5945 reloaded into a register of class CLASS. If X is a constant, or if 5946 X is a PLUS that contains a constant, check that the constant is a 5947 legitimate operand and that we are supposed to be able to load 5948 it into the register. 5949 5950 If not, force the constant into memory and reload the MEM instead. 5951 5952 MODE is the mode to use, in case X is an integer constant. 5953 5954 OPNUM and TYPE describe the purpose of any reloads made. 5955 5956 IND_LEVELS says how many levels of indirect addressing this machine 5957 supports. */ 5958 5959static void 5960find_reloads_address_part (rtx x, rtx *loc, enum reg_class class, 5961 enum machine_mode mode, int opnum, 5962 enum reload_type type, int ind_levels) 5963{ 5964 if (CONSTANT_P (x) 5965 && (! LEGITIMATE_CONSTANT_P (x) 5966 || PREFERRED_RELOAD_CLASS (x, class) == NO_REGS)) 5967 { 5968 rtx tem; 5969 5970 tem = x = force_const_mem (mode, x); 5971 find_reloads_address (mode, &tem, XEXP (tem, 0), &XEXP (tem, 0), 5972 opnum, type, ind_levels, 0); 5973 } 5974 5975 else if (GET_CODE (x) == PLUS 5976 && CONSTANT_P (XEXP (x, 1)) 5977 && (! LEGITIMATE_CONSTANT_P (XEXP (x, 1)) 5978 || PREFERRED_RELOAD_CLASS (XEXP (x, 1), class) == NO_REGS)) 5979 { 5980 rtx tem; 5981 5982 tem = force_const_mem (GET_MODE (x), XEXP (x, 1)); 5983 x = gen_rtx_PLUS (GET_MODE (x), XEXP (x, 0), tem); 5984 find_reloads_address (mode, &tem, XEXP (tem, 0), &XEXP (tem, 0), 5985 opnum, type, ind_levels, 0); 5986 } 5987 5988 push_reload (x, NULL_RTX, loc, (rtx*) 0, class, 5989 mode, VOIDmode, 0, 0, opnum, type); 5990} 5991 5992/* X, a subreg of a pseudo, is a part of an address that needs to be 5993 reloaded. 5994 5995 If the pseudo is equivalent to a memory location that cannot be directly 5996 addressed, make the necessary address reloads. 5997 5998 If address reloads have been necessary, or if the address is changed 5999 by register elimination, return the rtx of the memory location; 6000 otherwise, return X. 6001 6002 If FORCE_REPLACE is nonzero, unconditionally replace the subreg with the 6003 memory location. 6004 6005 OPNUM and TYPE identify the purpose of the reload. 6006 6007 IND_LEVELS says how many levels of indirect addressing are 6008 supported at this point in the address. 6009 6010 INSN, if nonzero, is the insn in which we do the reload. It is used 6011 to determine where to put USEs for pseudos that we have to replace with 6012 stack slots. */ 6013 6014static rtx 6015find_reloads_subreg_address (rtx x, int force_replace, int opnum, 6016 enum reload_type type, int ind_levels, rtx insn) 6017{ 6018 int regno = REGNO (SUBREG_REG (x)); 6019 6020 if (reg_equiv_memory_loc[regno]) 6021 { 6022 /* If the address is not directly addressable, or if the address is not 6023 offsettable, then it must be replaced. */ 6024 if (! force_replace 6025 && (reg_equiv_address[regno] 6026 || ! offsettable_memref_p (reg_equiv_mem[regno]))) 6027 force_replace = 1; 6028 6029 if (force_replace || num_not_at_initial_offset) 6030 { 6031 rtx tem = make_memloc (SUBREG_REG (x), regno); 6032 6033 /* If the address changes because of register elimination, then 6034 it must be replaced. */ 6035 if (force_replace 6036 || ! rtx_equal_p (tem, reg_equiv_mem[regno])) 6037 { 6038 unsigned outer_size = GET_MODE_SIZE (GET_MODE (x)); 6039 unsigned inner_size = GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))); 6040 int offset; 6041 rtx orig = tem; 6042 enum machine_mode orig_mode = GET_MODE (orig); 6043 int reloaded; 6044 6045 /* For big-endian paradoxical subregs, SUBREG_BYTE does not 6046 hold the correct (negative) byte offset. */ 6047 if (BYTES_BIG_ENDIAN && outer_size > inner_size) 6048 offset = inner_size - outer_size; 6049 else 6050 offset = SUBREG_BYTE (x); 6051 6052 XEXP (tem, 0) = plus_constant (XEXP (tem, 0), offset); 6053 PUT_MODE (tem, GET_MODE (x)); 6054 6055 /* If this was a paradoxical subreg that we replaced, the 6056 resulting memory must be sufficiently aligned to allow 6057 us to widen the mode of the memory. */ 6058 if (outer_size > inner_size) 6059 { 6060 rtx base; 6061 6062 base = XEXP (tem, 0); 6063 if (GET_CODE (base) == PLUS) 6064 { 6065 if (GET_CODE (XEXP (base, 1)) == CONST_INT 6066 && INTVAL (XEXP (base, 1)) % outer_size != 0) 6067 return x; 6068 base = XEXP (base, 0); 6069 } 6070 if (!REG_P (base) 6071 || (REGNO_POINTER_ALIGN (REGNO (base)) 6072 < outer_size * BITS_PER_UNIT)) 6073 return x; 6074 } 6075 6076 reloaded = find_reloads_address (GET_MODE (tem), &tem, 6077 XEXP (tem, 0), &XEXP (tem, 0), 6078 opnum, type, ind_levels, insn); 6079 /* ??? Do we need to handle nonzero offsets somehow? */ 6080 if (!offset && tem != orig) 6081 push_reg_equiv_alt_mem (regno, tem); 6082 6083 /* For some processors an address may be valid in the 6084 original mode but not in a smaller mode. For 6085 example, ARM accepts a scaled index register in 6086 SImode but not in HImode. find_reloads_address 6087 assumes that we pass it a valid address, and doesn't 6088 force a reload. This will probably be fine if 6089 find_reloads_address finds some reloads. But if it 6090 doesn't find any, then we may have just converted a 6091 valid address into an invalid one. Check for that 6092 here. */ 6093 if (reloaded != 1 6094 && strict_memory_address_p (orig_mode, XEXP (tem, 0)) 6095 && !strict_memory_address_p (GET_MODE (tem), 6096 XEXP (tem, 0))) 6097 push_reload (XEXP (tem, 0), NULL_RTX, &XEXP (tem, 0), (rtx*) 0, 6098 base_reg_class (GET_MODE (tem), MEM, SCRATCH), 6099 GET_MODE (XEXP (tem, 0)), VOIDmode, 0, 0, 6100 opnum, type); 6101 6102 /* If this is not a toplevel operand, find_reloads doesn't see 6103 this substitution. We have to emit a USE of the pseudo so 6104 that delete_output_reload can see it. */ 6105 if (replace_reloads && recog_data.operand[opnum] != x) 6106 /* We mark the USE with QImode so that we recognize it 6107 as one that can be safely deleted at the end of 6108 reload. */ 6109 PUT_MODE (emit_insn_before (gen_rtx_USE (VOIDmode, 6110 SUBREG_REG (x)), 6111 insn), QImode); 6112 x = tem; 6113 } 6114 } 6115 } 6116 return x; 6117} 6118 6119/* Substitute into the current INSN the registers into which we have reloaded 6120 the things that need reloading. The array `replacements' 6121 contains the locations of all pointers that must be changed 6122 and says what to replace them with. 6123 6124 Return the rtx that X translates into; usually X, but modified. */ 6125 6126void 6127subst_reloads (rtx insn) 6128{ 6129 int i; 6130 6131 for (i = 0; i < n_replacements; i++) 6132 { 6133 struct replacement *r = &replacements[i]; 6134 rtx reloadreg = rld[r->what].reg_rtx; 6135 if (reloadreg) 6136 { 6137#ifdef ENABLE_CHECKING 6138 /* Internal consistency test. Check that we don't modify 6139 anything in the equivalence arrays. Whenever something from 6140 those arrays needs to be reloaded, it must be unshared before 6141 being substituted into; the equivalence must not be modified. 6142 Otherwise, if the equivalence is used after that, it will 6143 have been modified, and the thing substituted (probably a 6144 register) is likely overwritten and not a usable equivalence. */ 6145 int check_regno; 6146 6147 for (check_regno = 0; check_regno < max_regno; check_regno++) 6148 { 6149#define CHECK_MODF(ARRAY) \ 6150 gcc_assert (!ARRAY[check_regno] \ 6151 || !loc_mentioned_in_p (r->where, \ 6152 ARRAY[check_regno])) 6153 6154 CHECK_MODF (reg_equiv_constant); 6155 CHECK_MODF (reg_equiv_memory_loc); 6156 CHECK_MODF (reg_equiv_address); 6157 CHECK_MODF (reg_equiv_mem); 6158#undef CHECK_MODF 6159 } 6160#endif /* ENABLE_CHECKING */ 6161 6162 /* If we're replacing a LABEL_REF with a register, add a 6163 REG_LABEL note to indicate to flow which label this 6164 register refers to. */ 6165 if (GET_CODE (*r->where) == LABEL_REF 6166 && JUMP_P (insn)) 6167 { 6168 REG_NOTES (insn) = gen_rtx_INSN_LIST (REG_LABEL, 6169 XEXP (*r->where, 0), 6170 REG_NOTES (insn)); 6171 JUMP_LABEL (insn) = XEXP (*r->where, 0); 6172 } 6173 6174 /* Encapsulate RELOADREG so its machine mode matches what 6175 used to be there. Note that gen_lowpart_common will 6176 do the wrong thing if RELOADREG is multi-word. RELOADREG 6177 will always be a REG here. */ 6178 if (GET_MODE (reloadreg) != r->mode && r->mode != VOIDmode) 6179 reloadreg = reload_adjust_reg_for_mode (reloadreg, r->mode); 6180 6181 /* If we are putting this into a SUBREG and RELOADREG is a 6182 SUBREG, we would be making nested SUBREGs, so we have to fix 6183 this up. Note that r->where == &SUBREG_REG (*r->subreg_loc). */ 6184 6185 if (r->subreg_loc != 0 && GET_CODE (reloadreg) == SUBREG) 6186 { 6187 if (GET_MODE (*r->subreg_loc) 6188 == GET_MODE (SUBREG_REG (reloadreg))) 6189 *r->subreg_loc = SUBREG_REG (reloadreg); 6190 else 6191 { 6192 int final_offset = 6193 SUBREG_BYTE (*r->subreg_loc) + SUBREG_BYTE (reloadreg); 6194 6195 /* When working with SUBREGs the rule is that the byte 6196 offset must be a multiple of the SUBREG's mode. */ 6197 final_offset = (final_offset / 6198 GET_MODE_SIZE (GET_MODE (*r->subreg_loc))); 6199 final_offset = (final_offset * 6200 GET_MODE_SIZE (GET_MODE (*r->subreg_loc))); 6201 6202 *r->where = SUBREG_REG (reloadreg); 6203 SUBREG_BYTE (*r->subreg_loc) = final_offset; 6204 } 6205 } 6206 else 6207 *r->where = reloadreg; 6208 } 6209 /* If reload got no reg and isn't optional, something's wrong. */ 6210 else 6211 gcc_assert (rld[r->what].optional); 6212 } 6213} 6214 6215/* Make a copy of any replacements being done into X and move those 6216 copies to locations in Y, a copy of X. */ 6217 6218void 6219copy_replacements (rtx x, rtx y) 6220{ 6221 /* We can't support X being a SUBREG because we might then need to know its 6222 location if something inside it was replaced. */ 6223 gcc_assert (GET_CODE (x) != SUBREG); 6224 6225 copy_replacements_1 (&x, &y, n_replacements); 6226} 6227 6228static void 6229copy_replacements_1 (rtx *px, rtx *py, int orig_replacements) 6230{ 6231 int i, j; 6232 rtx x, y; 6233 struct replacement *r; 6234 enum rtx_code code; 6235 const char *fmt; 6236 6237 for (j = 0; j < orig_replacements; j++) 6238 { 6239 if (replacements[j].subreg_loc == px) 6240 { 6241 r = &replacements[n_replacements++]; 6242 r->where = replacements[j].where; 6243 r->subreg_loc = py; 6244 r->what = replacements[j].what; 6245 r->mode = replacements[j].mode; 6246 } 6247 else if (replacements[j].where == px) 6248 { 6249 r = &replacements[n_replacements++]; 6250 r->where = py; 6251 r->subreg_loc = 0; 6252 r->what = replacements[j].what; 6253 r->mode = replacements[j].mode; 6254 } 6255 } 6256 6257 x = *px; 6258 y = *py; 6259 code = GET_CODE (x); 6260 fmt = GET_RTX_FORMAT (code); 6261 6262 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 6263 { 6264 if (fmt[i] == 'e') 6265 copy_replacements_1 (&XEXP (x, i), &XEXP (y, i), orig_replacements); 6266 else if (fmt[i] == 'E') 6267 for (j = XVECLEN (x, i); --j >= 0; ) 6268 copy_replacements_1 (&XVECEXP (x, i, j), &XVECEXP (y, i, j), 6269 orig_replacements); 6270 } 6271} 6272 6273/* Change any replacements being done to *X to be done to *Y. */ 6274 6275void 6276move_replacements (rtx *x, rtx *y) 6277{ 6278 int i; 6279 6280 for (i = 0; i < n_replacements; i++) 6281 if (replacements[i].subreg_loc == x) 6282 replacements[i].subreg_loc = y; 6283 else if (replacements[i].where == x) 6284 { 6285 replacements[i].where = y; 6286 replacements[i].subreg_loc = 0; 6287 } 6288} 6289 6290/* If LOC was scheduled to be replaced by something, return the replacement. 6291 Otherwise, return *LOC. */ 6292 6293rtx 6294find_replacement (rtx *loc) 6295{ 6296 struct replacement *r; 6297 6298 for (r = &replacements[0]; r < &replacements[n_replacements]; r++) 6299 { 6300 rtx reloadreg = rld[r->what].reg_rtx; 6301 6302 if (reloadreg && r->where == loc) 6303 { 6304 if (r->mode != VOIDmode && GET_MODE (reloadreg) != r->mode) 6305 reloadreg = gen_rtx_REG (r->mode, REGNO (reloadreg)); 6306 6307 return reloadreg; 6308 } 6309 else if (reloadreg && r->subreg_loc == loc) 6310 { 6311 /* RELOADREG must be either a REG or a SUBREG. 6312 6313 ??? Is it actually still ever a SUBREG? If so, why? */ 6314 6315 if (REG_P (reloadreg)) 6316 return gen_rtx_REG (GET_MODE (*loc), 6317 (REGNO (reloadreg) + 6318 subreg_regno_offset (REGNO (SUBREG_REG (*loc)), 6319 GET_MODE (SUBREG_REG (*loc)), 6320 SUBREG_BYTE (*loc), 6321 GET_MODE (*loc)))); 6322 else if (GET_MODE (reloadreg) == GET_MODE (*loc)) 6323 return reloadreg; 6324 else 6325 { 6326 int final_offset = SUBREG_BYTE (reloadreg) + SUBREG_BYTE (*loc); 6327 6328 /* When working with SUBREGs the rule is that the byte 6329 offset must be a multiple of the SUBREG's mode. */ 6330 final_offset = (final_offset / GET_MODE_SIZE (GET_MODE (*loc))); 6331 final_offset = (final_offset * GET_MODE_SIZE (GET_MODE (*loc))); 6332 return gen_rtx_SUBREG (GET_MODE (*loc), SUBREG_REG (reloadreg), 6333 final_offset); 6334 } 6335 } 6336 } 6337 6338 /* If *LOC is a PLUS, MINUS, or MULT, see if a replacement is scheduled for 6339 what's inside and make a new rtl if so. */ 6340 if (GET_CODE (*loc) == PLUS || GET_CODE (*loc) == MINUS 6341 || GET_CODE (*loc) == MULT) 6342 { 6343 rtx x = find_replacement (&XEXP (*loc, 0)); 6344 rtx y = find_replacement (&XEXP (*loc, 1)); 6345 6346 if (x != XEXP (*loc, 0) || y != XEXP (*loc, 1)) 6347 return gen_rtx_fmt_ee (GET_CODE (*loc), GET_MODE (*loc), x, y); 6348 } 6349 6350 return *loc; 6351} 6352 6353/* Return nonzero if register in range [REGNO, ENDREGNO) 6354 appears either explicitly or implicitly in X 6355 other than being stored into (except for earlyclobber operands). 6356 6357 References contained within the substructure at LOC do not count. 6358 LOC may be zero, meaning don't ignore anything. 6359 6360 This is similar to refers_to_regno_p in rtlanal.c except that we 6361 look at equivalences for pseudos that didn't get hard registers. */ 6362 6363static int 6364refers_to_regno_for_reload_p (unsigned int regno, unsigned int endregno, 6365 rtx x, rtx *loc) 6366{ 6367 int i; 6368 unsigned int r; 6369 RTX_CODE code; 6370 const char *fmt; 6371 6372 if (x == 0) 6373 return 0; 6374 6375 repeat: 6376 code = GET_CODE (x); 6377 6378 switch (code) 6379 { 6380 case REG: 6381 r = REGNO (x); 6382 6383 /* If this is a pseudo, a hard register must not have been allocated. 6384 X must therefore either be a constant or be in memory. */ 6385 if (r >= FIRST_PSEUDO_REGISTER) 6386 { 6387 if (reg_equiv_memory_loc[r]) 6388 return refers_to_regno_for_reload_p (regno, endregno, 6389 reg_equiv_memory_loc[r], 6390 (rtx*) 0); 6391 6392 gcc_assert (reg_equiv_constant[r] || reg_equiv_invariant[r]); 6393 return 0; 6394 } 6395 6396 return (endregno > r 6397 && regno < r + (r < FIRST_PSEUDO_REGISTER 6398 ? hard_regno_nregs[r][GET_MODE (x)] 6399 : 1)); 6400 6401 case SUBREG: 6402 /* If this is a SUBREG of a hard reg, we can see exactly which 6403 registers are being modified. Otherwise, handle normally. */ 6404 if (REG_P (SUBREG_REG (x)) 6405 && REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER) 6406 { 6407 unsigned int inner_regno = subreg_regno (x); 6408 unsigned int inner_endregno 6409 = inner_regno + (inner_regno < FIRST_PSEUDO_REGISTER 6410 ? hard_regno_nregs[inner_regno][GET_MODE (x)] : 1); 6411 6412 return endregno > inner_regno && regno < inner_endregno; 6413 } 6414 break; 6415 6416 case CLOBBER: 6417 case SET: 6418 if (&SET_DEST (x) != loc 6419 /* Note setting a SUBREG counts as referring to the REG it is in for 6420 a pseudo but not for hard registers since we can 6421 treat each word individually. */ 6422 && ((GET_CODE (SET_DEST (x)) == SUBREG 6423 && loc != &SUBREG_REG (SET_DEST (x)) 6424 && REG_P (SUBREG_REG (SET_DEST (x))) 6425 && REGNO (SUBREG_REG (SET_DEST (x))) >= FIRST_PSEUDO_REGISTER 6426 && refers_to_regno_for_reload_p (regno, endregno, 6427 SUBREG_REG (SET_DEST (x)), 6428 loc)) 6429 /* If the output is an earlyclobber operand, this is 6430 a conflict. */ 6431 || ((!REG_P (SET_DEST (x)) 6432 || earlyclobber_operand_p (SET_DEST (x))) 6433 && refers_to_regno_for_reload_p (regno, endregno, 6434 SET_DEST (x), loc)))) 6435 return 1; 6436 6437 if (code == CLOBBER || loc == &SET_SRC (x)) 6438 return 0; 6439 x = SET_SRC (x); 6440 goto repeat; 6441 6442 default: 6443 break; 6444 } 6445 6446 /* X does not match, so try its subexpressions. */ 6447 6448 fmt = GET_RTX_FORMAT (code); 6449 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 6450 { 6451 if (fmt[i] == 'e' && loc != &XEXP (x, i)) 6452 { 6453 if (i == 0) 6454 { 6455 x = XEXP (x, 0); 6456 goto repeat; 6457 } 6458 else 6459 if (refers_to_regno_for_reload_p (regno, endregno, 6460 XEXP (x, i), loc)) 6461 return 1; 6462 } 6463 else if (fmt[i] == 'E') 6464 { 6465 int j; 6466 for (j = XVECLEN (x, i) - 1; j >= 0; j--) 6467 if (loc != &XVECEXP (x, i, j) 6468 && refers_to_regno_for_reload_p (regno, endregno, 6469 XVECEXP (x, i, j), loc)) 6470 return 1; 6471 } 6472 } 6473 return 0; 6474} 6475 6476/* Nonzero if modifying X will affect IN. If X is a register or a SUBREG, 6477 we check if any register number in X conflicts with the relevant register 6478 numbers. If X is a constant, return 0. If X is a MEM, return 1 iff IN 6479 contains a MEM (we don't bother checking for memory addresses that can't 6480 conflict because we expect this to be a rare case. 6481 6482 This function is similar to reg_overlap_mentioned_p in rtlanal.c except 6483 that we look at equivalences for pseudos that didn't get hard registers. */ 6484 6485int 6486reg_overlap_mentioned_for_reload_p (rtx x, rtx in) 6487{ 6488 int regno, endregno; 6489 6490 /* Overly conservative. */ 6491 if (GET_CODE (x) == STRICT_LOW_PART 6492 || GET_RTX_CLASS (GET_CODE (x)) == RTX_AUTOINC) 6493 x = XEXP (x, 0); 6494 6495 /* If either argument is a constant, then modifying X can not affect IN. */ 6496 if (CONSTANT_P (x) || CONSTANT_P (in)) 6497 return 0; 6498 else if (GET_CODE (x) == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM) 6499 return refers_to_mem_for_reload_p (in); 6500 else if (GET_CODE (x) == SUBREG) 6501 { 6502 regno = REGNO (SUBREG_REG (x)); 6503 if (regno < FIRST_PSEUDO_REGISTER) 6504 regno += subreg_regno_offset (REGNO (SUBREG_REG (x)), 6505 GET_MODE (SUBREG_REG (x)), 6506 SUBREG_BYTE (x), 6507 GET_MODE (x)); 6508 } 6509 else if (REG_P (x)) 6510 { 6511 regno = REGNO (x); 6512 6513 /* If this is a pseudo, it must not have been assigned a hard register. 6514 Therefore, it must either be in memory or be a constant. */ 6515 6516 if (regno >= FIRST_PSEUDO_REGISTER) 6517 { 6518 if (reg_equiv_memory_loc[regno]) 6519 return refers_to_mem_for_reload_p (in); 6520 gcc_assert (reg_equiv_constant[regno]); 6521 return 0; 6522 } 6523 } 6524 else if (MEM_P (x)) 6525 return refers_to_mem_for_reload_p (in); 6526 else if (GET_CODE (x) == SCRATCH || GET_CODE (x) == PC 6527 || GET_CODE (x) == CC0) 6528 return reg_mentioned_p (x, in); 6529 else 6530 { 6531 gcc_assert (GET_CODE (x) == PLUS); 6532 6533 /* We actually want to know if X is mentioned somewhere inside IN. 6534 We must not say that (plus (sp) (const_int 124)) is in 6535 (plus (sp) (const_int 64)), since that can lead to incorrect reload 6536 allocation when spuriously changing a RELOAD_FOR_OUTPUT_ADDRESS 6537 into a RELOAD_OTHER on behalf of another RELOAD_OTHER. */ 6538 while (MEM_P (in)) 6539 in = XEXP (in, 0); 6540 if (REG_P (in)) 6541 return 0; 6542 else if (GET_CODE (in) == PLUS) 6543 return (rtx_equal_p (x, in) 6544 || reg_overlap_mentioned_for_reload_p (x, XEXP (in, 0)) 6545 || reg_overlap_mentioned_for_reload_p (x, XEXP (in, 1))); 6546 else return (reg_overlap_mentioned_for_reload_p (XEXP (x, 0), in) 6547 || reg_overlap_mentioned_for_reload_p (XEXP (x, 1), in)); 6548 } 6549 6550 endregno = regno + (regno < FIRST_PSEUDO_REGISTER 6551 ? hard_regno_nregs[regno][GET_MODE (x)] : 1); 6552 6553 return refers_to_regno_for_reload_p (regno, endregno, in, (rtx*) 0); 6554} 6555 6556/* Return nonzero if anything in X contains a MEM. Look also for pseudo 6557 registers. */ 6558 6559static int 6560refers_to_mem_for_reload_p (rtx x) 6561{ 6562 const char *fmt; 6563 int i; 6564 6565 if (MEM_P (x)) 6566 return 1; 6567 6568 if (REG_P (x)) 6569 return (REGNO (x) >= FIRST_PSEUDO_REGISTER 6570 && reg_equiv_memory_loc[REGNO (x)]); 6571 6572 fmt = GET_RTX_FORMAT (GET_CODE (x)); 6573 for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--) 6574 if (fmt[i] == 'e' 6575 && (MEM_P (XEXP (x, i)) 6576 || refers_to_mem_for_reload_p (XEXP (x, i)))) 6577 return 1; 6578 6579 return 0; 6580} 6581 6582/* Check the insns before INSN to see if there is a suitable register 6583 containing the same value as GOAL. 6584 If OTHER is -1, look for a register in class CLASS. 6585 Otherwise, just see if register number OTHER shares GOAL's value. 6586 6587 Return an rtx for the register found, or zero if none is found. 6588 6589 If RELOAD_REG_P is (short *)1, 6590 we reject any hard reg that appears in reload_reg_rtx 6591 because such a hard reg is also needed coming into this insn. 6592 6593 If RELOAD_REG_P is any other nonzero value, 6594 it is a vector indexed by hard reg number 6595 and we reject any hard reg whose element in the vector is nonnegative 6596 as well as any that appears in reload_reg_rtx. 6597 6598 If GOAL is zero, then GOALREG is a register number; we look 6599 for an equivalent for that register. 6600 6601 MODE is the machine mode of the value we want an equivalence for. 6602 If GOAL is nonzero and not VOIDmode, then it must have mode MODE. 6603 6604 This function is used by jump.c as well as in the reload pass. 6605 6606 If GOAL is the sum of the stack pointer and a constant, we treat it 6607 as if it were a constant except that sp is required to be unchanging. */ 6608 6609rtx 6610find_equiv_reg (rtx goal, rtx insn, enum reg_class class, int other, 6611 short *reload_reg_p, int goalreg, enum machine_mode mode) 6612{ 6613 rtx p = insn; 6614 rtx goaltry, valtry, value, where; 6615 rtx pat; 6616 int regno = -1; 6617 int valueno; 6618 int goal_mem = 0; 6619 int goal_const = 0; 6620 int goal_mem_addr_varies = 0; 6621 int need_stable_sp = 0; 6622 int nregs; 6623 int valuenregs; 6624 int num = 0; 6625 6626 if (goal == 0) 6627 regno = goalreg; 6628 else if (REG_P (goal)) 6629 regno = REGNO (goal); 6630 else if (MEM_P (goal)) 6631 { 6632 enum rtx_code code = GET_CODE (XEXP (goal, 0)); 6633 if (MEM_VOLATILE_P (goal)) 6634 return 0; 6635 if (flag_float_store && SCALAR_FLOAT_MODE_P (GET_MODE (goal))) 6636 return 0; 6637 /* An address with side effects must be reexecuted. */ 6638 switch (code) 6639 { 6640 case POST_INC: 6641 case PRE_INC: 6642 case POST_DEC: 6643 case PRE_DEC: 6644 case POST_MODIFY: 6645 case PRE_MODIFY: 6646 return 0; 6647 default: 6648 break; 6649 } 6650 goal_mem = 1; 6651 } 6652 else if (CONSTANT_P (goal)) 6653 goal_const = 1; 6654 else if (GET_CODE (goal) == PLUS 6655 && XEXP (goal, 0) == stack_pointer_rtx 6656 && CONSTANT_P (XEXP (goal, 1))) 6657 goal_const = need_stable_sp = 1; 6658 else if (GET_CODE (goal) == PLUS 6659 && XEXP (goal, 0) == frame_pointer_rtx 6660 && CONSTANT_P (XEXP (goal, 1))) 6661 goal_const = 1; 6662 else 6663 return 0; 6664 6665 num = 0; 6666 /* Scan insns back from INSN, looking for one that copies 6667 a value into or out of GOAL. 6668 Stop and give up if we reach a label. */ 6669 6670 while (1) 6671 { 6672 p = PREV_INSN (p); 6673 num++; 6674 if (p == 0 || LABEL_P (p) 6675 || num > PARAM_VALUE (PARAM_MAX_RELOAD_SEARCH_INSNS)) 6676 return 0; 6677 6678 if (NONJUMP_INSN_P (p) 6679 /* If we don't want spill regs ... */ 6680 && (! (reload_reg_p != 0 6681 && reload_reg_p != (short *) (HOST_WIDE_INT) 1) 6682 /* ... then ignore insns introduced by reload; they aren't 6683 useful and can cause results in reload_as_needed to be 6684 different from what they were when calculating the need for 6685 spills. If we notice an input-reload insn here, we will 6686 reject it below, but it might hide a usable equivalent. 6687 That makes bad code. It may even fail: perhaps no reg was 6688 spilled for this insn because it was assumed we would find 6689 that equivalent. */ 6690 || INSN_UID (p) < reload_first_uid)) 6691 { 6692 rtx tem; 6693 pat = single_set (p); 6694 6695 /* First check for something that sets some reg equal to GOAL. */ 6696 if (pat != 0 6697 && ((regno >= 0 6698 && true_regnum (SET_SRC (pat)) == regno 6699 && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0) 6700 || 6701 (regno >= 0 6702 && true_regnum (SET_DEST (pat)) == regno 6703 && (valueno = true_regnum (valtry = SET_SRC (pat))) >= 0) 6704 || 6705 (goal_const && rtx_equal_p (SET_SRC (pat), goal) 6706 /* When looking for stack pointer + const, 6707 make sure we don't use a stack adjust. */ 6708 && !reg_overlap_mentioned_for_reload_p (SET_DEST (pat), goal) 6709 && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0) 6710 || (goal_mem 6711 && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0 6712 && rtx_renumbered_equal_p (goal, SET_SRC (pat))) 6713 || (goal_mem 6714 && (valueno = true_regnum (valtry = SET_SRC (pat))) >= 0 6715 && rtx_renumbered_equal_p (goal, SET_DEST (pat))) 6716 /* If we are looking for a constant, 6717 and something equivalent to that constant was copied 6718 into a reg, we can use that reg. */ 6719 || (goal_const && REG_NOTES (p) != 0 6720 && (tem = find_reg_note (p, REG_EQUIV, NULL_RTX)) 6721 && ((rtx_equal_p (XEXP (tem, 0), goal) 6722 && (valueno 6723 = true_regnum (valtry = SET_DEST (pat))) >= 0) 6724 || (REG_P (SET_DEST (pat)) 6725 && GET_CODE (XEXP (tem, 0)) == CONST_DOUBLE 6726 && SCALAR_FLOAT_MODE_P (GET_MODE (XEXP (tem, 0))) 6727 && GET_CODE (goal) == CONST_INT 6728 && 0 != (goaltry 6729 = operand_subword (XEXP (tem, 0), 0, 0, 6730 VOIDmode)) 6731 && rtx_equal_p (goal, goaltry) 6732 && (valtry 6733 = operand_subword (SET_DEST (pat), 0, 0, 6734 VOIDmode)) 6735 && (valueno = true_regnum (valtry)) >= 0))) 6736 || (goal_const && (tem = find_reg_note (p, REG_EQUIV, 6737 NULL_RTX)) 6738 && REG_P (SET_DEST (pat)) 6739 && GET_CODE (XEXP (tem, 0)) == CONST_DOUBLE 6740 && SCALAR_FLOAT_MODE_P (GET_MODE (XEXP (tem, 0))) 6741 && GET_CODE (goal) == CONST_INT 6742 && 0 != (goaltry = operand_subword (XEXP (tem, 0), 1, 0, 6743 VOIDmode)) 6744 && rtx_equal_p (goal, goaltry) 6745 && (valtry 6746 = operand_subword (SET_DEST (pat), 1, 0, VOIDmode)) 6747 && (valueno = true_regnum (valtry)) >= 0))) 6748 { 6749 if (other >= 0) 6750 { 6751 if (valueno != other) 6752 continue; 6753 } 6754 else if ((unsigned) valueno >= FIRST_PSEUDO_REGISTER) 6755 continue; 6756 else 6757 { 6758 int i; 6759 6760 for (i = hard_regno_nregs[valueno][mode] - 1; i >= 0; i--) 6761 if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], 6762 valueno + i)) 6763 break; 6764 if (i >= 0) 6765 continue; 6766 } 6767 value = valtry; 6768 where = p; 6769 break; 6770 } 6771 } 6772 } 6773 6774 /* We found a previous insn copying GOAL into a suitable other reg VALUE 6775 (or copying VALUE into GOAL, if GOAL is also a register). 6776 Now verify that VALUE is really valid. */ 6777 6778 /* VALUENO is the register number of VALUE; a hard register. */ 6779 6780 /* Don't try to re-use something that is killed in this insn. We want 6781 to be able to trust REG_UNUSED notes. */ 6782 if (REG_NOTES (where) != 0 && find_reg_note (where, REG_UNUSED, value)) 6783 return 0; 6784 6785 /* If we propose to get the value from the stack pointer or if GOAL is 6786 a MEM based on the stack pointer, we need a stable SP. */ 6787 if (valueno == STACK_POINTER_REGNUM || regno == STACK_POINTER_REGNUM 6788 || (goal_mem && reg_overlap_mentioned_for_reload_p (stack_pointer_rtx, 6789 goal))) 6790 need_stable_sp = 1; 6791 6792 /* Reject VALUE if the copy-insn moved the wrong sort of datum. */ 6793 if (GET_MODE (value) != mode) 6794 return 0; 6795 6796 /* Reject VALUE if it was loaded from GOAL 6797 and is also a register that appears in the address of GOAL. */ 6798 6799 if (goal_mem && value == SET_DEST (single_set (where)) 6800 && refers_to_regno_for_reload_p (valueno, 6801 (valueno 6802 + hard_regno_nregs[valueno][mode]), 6803 goal, (rtx*) 0)) 6804 return 0; 6805 6806 /* Reject registers that overlap GOAL. */ 6807 6808 if (regno >= 0 && regno < FIRST_PSEUDO_REGISTER) 6809 nregs = hard_regno_nregs[regno][mode]; 6810 else 6811 nregs = 1; 6812 valuenregs = hard_regno_nregs[valueno][mode]; 6813 6814 if (!goal_mem && !goal_const 6815 && regno + nregs > valueno && regno < valueno + valuenregs) 6816 return 0; 6817 6818 /* Reject VALUE if it is one of the regs reserved for reloads. 6819 Reload1 knows how to reuse them anyway, and it would get 6820 confused if we allocated one without its knowledge. 6821 (Now that insns introduced by reload are ignored above, 6822 this case shouldn't happen, but I'm not positive.) */ 6823 6824 if (reload_reg_p != 0 && reload_reg_p != (short *) (HOST_WIDE_INT) 1) 6825 { 6826 int i; 6827 for (i = 0; i < valuenregs; ++i) 6828 if (reload_reg_p[valueno + i] >= 0) 6829 return 0; 6830 } 6831 6832 /* Reject VALUE if it is a register being used for an input reload 6833 even if it is not one of those reserved. */ 6834 6835 if (reload_reg_p != 0) 6836 { 6837 int i; 6838 for (i = 0; i < n_reloads; i++) 6839 if (rld[i].reg_rtx != 0 && rld[i].in) 6840 { 6841 int regno1 = REGNO (rld[i].reg_rtx); 6842 int nregs1 = hard_regno_nregs[regno1] 6843 [GET_MODE (rld[i].reg_rtx)]; 6844 if (regno1 < valueno + valuenregs 6845 && regno1 + nregs1 > valueno) 6846 return 0; 6847 } 6848 } 6849 6850 if (goal_mem) 6851 /* We must treat frame pointer as varying here, 6852 since it can vary--in a nonlocal goto as generated by expand_goto. */ 6853 goal_mem_addr_varies = !CONSTANT_ADDRESS_P (XEXP (goal, 0)); 6854 6855 /* Now verify that the values of GOAL and VALUE remain unaltered 6856 until INSN is reached. */ 6857 6858 p = insn; 6859 while (1) 6860 { 6861 p = PREV_INSN (p); 6862 if (p == where) 6863 return value; 6864 6865 /* Don't trust the conversion past a function call 6866 if either of the two is in a call-clobbered register, or memory. */ 6867 if (CALL_P (p)) 6868 { 6869 int i; 6870 6871 if (goal_mem || need_stable_sp) 6872 return 0; 6873 6874 if (regno >= 0 && regno < FIRST_PSEUDO_REGISTER) 6875 for (i = 0; i < nregs; ++i) 6876 if (call_used_regs[regno + i] 6877 || HARD_REGNO_CALL_PART_CLOBBERED (regno + i, mode)) 6878 return 0; 6879 6880 if (valueno >= 0 && valueno < FIRST_PSEUDO_REGISTER) 6881 for (i = 0; i < valuenregs; ++i) 6882 if (call_used_regs[valueno + i] 6883 || HARD_REGNO_CALL_PART_CLOBBERED (valueno + i, mode)) 6884 return 0; 6885 } 6886 6887 if (INSN_P (p)) 6888 { 6889 pat = PATTERN (p); 6890 6891 /* Watch out for unspec_volatile, and volatile asms. */ 6892 if (volatile_insn_p (pat)) 6893 return 0; 6894 6895 /* If this insn P stores in either GOAL or VALUE, return 0. 6896 If GOAL is a memory ref and this insn writes memory, return 0. 6897 If GOAL is a memory ref and its address is not constant, 6898 and this insn P changes a register used in GOAL, return 0. */ 6899 6900 if (GET_CODE (pat) == COND_EXEC) 6901 pat = COND_EXEC_CODE (pat); 6902 if (GET_CODE (pat) == SET || GET_CODE (pat) == CLOBBER) 6903 { 6904 rtx dest = SET_DEST (pat); 6905 while (GET_CODE (dest) == SUBREG 6906 || GET_CODE (dest) == ZERO_EXTRACT 6907 || GET_CODE (dest) == STRICT_LOW_PART) 6908 dest = XEXP (dest, 0); 6909 if (REG_P (dest)) 6910 { 6911 int xregno = REGNO (dest); 6912 int xnregs; 6913 if (REGNO (dest) < FIRST_PSEUDO_REGISTER) 6914 xnregs = hard_regno_nregs[xregno][GET_MODE (dest)]; 6915 else 6916 xnregs = 1; 6917 if (xregno < regno + nregs && xregno + xnregs > regno) 6918 return 0; 6919 if (xregno < valueno + valuenregs 6920 && xregno + xnregs > valueno) 6921 return 0; 6922 if (goal_mem_addr_varies 6923 && reg_overlap_mentioned_for_reload_p (dest, goal)) 6924 return 0; 6925 if (xregno == STACK_POINTER_REGNUM && need_stable_sp) 6926 return 0; 6927 } 6928 else if (goal_mem && MEM_P (dest) 6929 && ! push_operand (dest, GET_MODE (dest))) 6930 return 0; 6931 else if (MEM_P (dest) && regno >= FIRST_PSEUDO_REGISTER 6932 && reg_equiv_memory_loc[regno] != 0) 6933 return 0; 6934 else if (need_stable_sp && push_operand (dest, GET_MODE (dest))) 6935 return 0; 6936 } 6937 else if (GET_CODE (pat) == PARALLEL) 6938 { 6939 int i; 6940 for (i = XVECLEN (pat, 0) - 1; i >= 0; i--) 6941 { 6942 rtx v1 = XVECEXP (pat, 0, i); 6943 if (GET_CODE (v1) == COND_EXEC) 6944 v1 = COND_EXEC_CODE (v1); 6945 if (GET_CODE (v1) == SET || GET_CODE (v1) == CLOBBER) 6946 { 6947 rtx dest = SET_DEST (v1); 6948 while (GET_CODE (dest) == SUBREG 6949 || GET_CODE (dest) == ZERO_EXTRACT 6950 || GET_CODE (dest) == STRICT_LOW_PART) 6951 dest = XEXP (dest, 0); 6952 if (REG_P (dest)) 6953 { 6954 int xregno = REGNO (dest); 6955 int xnregs; 6956 if (REGNO (dest) < FIRST_PSEUDO_REGISTER) 6957 xnregs = hard_regno_nregs[xregno][GET_MODE (dest)]; 6958 else 6959 xnregs = 1; 6960 if (xregno < regno + nregs 6961 && xregno + xnregs > regno) 6962 return 0; 6963 if (xregno < valueno + valuenregs 6964 && xregno + xnregs > valueno) 6965 return 0; 6966 if (goal_mem_addr_varies 6967 && reg_overlap_mentioned_for_reload_p (dest, 6968 goal)) 6969 return 0; 6970 if (xregno == STACK_POINTER_REGNUM && need_stable_sp) 6971 return 0; 6972 } 6973 else if (goal_mem && MEM_P (dest) 6974 && ! push_operand (dest, GET_MODE (dest))) 6975 return 0; 6976 else if (MEM_P (dest) && regno >= FIRST_PSEUDO_REGISTER 6977 && reg_equiv_memory_loc[regno] != 0) 6978 return 0; 6979 else if (need_stable_sp 6980 && push_operand (dest, GET_MODE (dest))) 6981 return 0; 6982 } 6983 } 6984 } 6985 6986 if (CALL_P (p) && CALL_INSN_FUNCTION_USAGE (p)) 6987 { 6988 rtx link; 6989 6990 for (link = CALL_INSN_FUNCTION_USAGE (p); XEXP (link, 1) != 0; 6991 link = XEXP (link, 1)) 6992 { 6993 pat = XEXP (link, 0); 6994 if (GET_CODE (pat) == CLOBBER) 6995 { 6996 rtx dest = SET_DEST (pat); 6997 6998 if (REG_P (dest)) 6999 { 7000 int xregno = REGNO (dest); 7001 int xnregs 7002 = hard_regno_nregs[xregno][GET_MODE (dest)]; 7003 7004 if (xregno < regno + nregs 7005 && xregno + xnregs > regno) 7006 return 0; 7007 else if (xregno < valueno + valuenregs 7008 && xregno + xnregs > valueno) 7009 return 0; 7010 else if (goal_mem_addr_varies 7011 && reg_overlap_mentioned_for_reload_p (dest, 7012 goal)) 7013 return 0; 7014 } 7015 7016 else if (goal_mem && MEM_P (dest) 7017 && ! push_operand (dest, GET_MODE (dest))) 7018 return 0; 7019 else if (need_stable_sp 7020 && push_operand (dest, GET_MODE (dest))) 7021 return 0; 7022 } 7023 } 7024 } 7025 7026#ifdef AUTO_INC_DEC 7027 /* If this insn auto-increments or auto-decrements 7028 either regno or valueno, return 0 now. 7029 If GOAL is a memory ref and its address is not constant, 7030 and this insn P increments a register used in GOAL, return 0. */ 7031 { 7032 rtx link; 7033 7034 for (link = REG_NOTES (p); link; link = XEXP (link, 1)) 7035 if (REG_NOTE_KIND (link) == REG_INC 7036 && REG_P (XEXP (link, 0))) 7037 { 7038 int incno = REGNO (XEXP (link, 0)); 7039 if (incno < regno + nregs && incno >= regno) 7040 return 0; 7041 if (incno < valueno + valuenregs && incno >= valueno) 7042 return 0; 7043 if (goal_mem_addr_varies 7044 && reg_overlap_mentioned_for_reload_p (XEXP (link, 0), 7045 goal)) 7046 return 0; 7047 } 7048 } 7049#endif 7050 } 7051 } 7052} 7053 7054/* Find a place where INCED appears in an increment or decrement operator 7055 within X, and return the amount INCED is incremented or decremented by. 7056 The value is always positive. */ 7057 7058static int 7059find_inc_amount (rtx x, rtx inced) 7060{ 7061 enum rtx_code code = GET_CODE (x); 7062 const char *fmt; 7063 int i; 7064 7065 if (code == MEM) 7066 { 7067 rtx addr = XEXP (x, 0); 7068 if ((GET_CODE (addr) == PRE_DEC 7069 || GET_CODE (addr) == POST_DEC 7070 || GET_CODE (addr) == PRE_INC 7071 || GET_CODE (addr) == POST_INC) 7072 && XEXP (addr, 0) == inced) 7073 return GET_MODE_SIZE (GET_MODE (x)); 7074 else if ((GET_CODE (addr) == PRE_MODIFY 7075 || GET_CODE (addr) == POST_MODIFY) 7076 && GET_CODE (XEXP (addr, 1)) == PLUS 7077 && XEXP (addr, 0) == XEXP (XEXP (addr, 1), 0) 7078 && XEXP (addr, 0) == inced 7079 && GET_CODE (XEXP (XEXP (addr, 1), 1)) == CONST_INT) 7080 { 7081 i = INTVAL (XEXP (XEXP (addr, 1), 1)); 7082 return i < 0 ? -i : i; 7083 } 7084 } 7085 7086 fmt = GET_RTX_FORMAT (code); 7087 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) 7088 { 7089 if (fmt[i] == 'e') 7090 { 7091 int tem = find_inc_amount (XEXP (x, i), inced); 7092 if (tem != 0) 7093 return tem; 7094 } 7095 if (fmt[i] == 'E') 7096 { 7097 int j; 7098 for (j = XVECLEN (x, i) - 1; j >= 0; j--) 7099 { 7100 int tem = find_inc_amount (XVECEXP (x, i, j), inced); 7101 if (tem != 0) 7102 return tem; 7103 } 7104 } 7105 } 7106 7107 return 0; 7108} 7109 7110/* Return 1 if registers from REGNO to ENDREGNO are the subjects of a 7111 REG_INC note in insn INSN. REGNO must refer to a hard register. */ 7112 7113#ifdef AUTO_INC_DEC 7114static int 7115reg_inc_found_and_valid_p (unsigned int regno, unsigned int endregno, 7116 rtx insn) 7117{ 7118 rtx link; 7119 7120 gcc_assert (insn); 7121 7122 if (! INSN_P (insn)) 7123 return 0; 7124 7125 for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) 7126 if (REG_NOTE_KIND (link) == REG_INC) 7127 { 7128 unsigned int test = (int) REGNO (XEXP (link, 0)); 7129 if (test >= regno && test < endregno) 7130 return 1; 7131 } 7132 return 0; 7133} 7134#else 7135 7136#define reg_inc_found_and_valid_p(regno,endregno,insn) 0 7137 7138#endif 7139 7140/* Return 1 if register REGNO is the subject of a clobber in insn INSN. 7141 If SETS is 1, also consider SETs. If SETS is 2, enable checking 7142 REG_INC. REGNO must refer to a hard register. */ 7143 7144int 7145regno_clobbered_p (unsigned int regno, rtx insn, enum machine_mode mode, 7146 int sets) 7147{ 7148 unsigned int nregs, endregno; 7149 7150 /* regno must be a hard register. */ 7151 gcc_assert (regno < FIRST_PSEUDO_REGISTER); 7152 7153 nregs = hard_regno_nregs[regno][mode]; 7154 endregno = regno + nregs; 7155 7156 if ((GET_CODE (PATTERN (insn)) == CLOBBER 7157 || (sets == 1 && GET_CODE (PATTERN (insn)) == SET)) 7158 && REG_P (XEXP (PATTERN (insn), 0))) 7159 { 7160 unsigned int test = REGNO (XEXP (PATTERN (insn), 0)); 7161 7162 return test >= regno && test < endregno; 7163 } 7164 7165 if (sets == 2 && reg_inc_found_and_valid_p (regno, endregno, insn)) 7166 return 1; 7167 7168 if (GET_CODE (PATTERN (insn)) == PARALLEL) 7169 { 7170 int i = XVECLEN (PATTERN (insn), 0) - 1; 7171 7172 for (; i >= 0; i--) 7173 { 7174 rtx elt = XVECEXP (PATTERN (insn), 0, i); 7175 if ((GET_CODE (elt) == CLOBBER 7176 || (sets == 1 && GET_CODE (PATTERN (insn)) == SET)) 7177 && REG_P (XEXP (elt, 0))) 7178 { 7179 unsigned int test = REGNO (XEXP (elt, 0)); 7180 7181 if (test >= regno && test < endregno) 7182 return 1; 7183 } 7184 if (sets == 2 7185 && reg_inc_found_and_valid_p (regno, endregno, elt)) 7186 return 1; 7187 } 7188 } 7189 7190 return 0; 7191} 7192 7193/* Find the low part, with mode MODE, of a hard regno RELOADREG. */ 7194rtx 7195reload_adjust_reg_for_mode (rtx reloadreg, enum machine_mode mode) 7196{ 7197 int regno; 7198 7199 if (GET_MODE (reloadreg) == mode) 7200 return reloadreg; 7201 7202 regno = REGNO (reloadreg); 7203 7204 if (WORDS_BIG_ENDIAN) 7205 regno += (int) hard_regno_nregs[regno][GET_MODE (reloadreg)] 7206 - (int) hard_regno_nregs[regno][mode]; 7207 7208 return gen_rtx_REG (mode, regno); 7209} 7210 7211static const char *const reload_when_needed_name[] = 7212{ 7213 "RELOAD_FOR_INPUT", 7214 "RELOAD_FOR_OUTPUT", 7215 "RELOAD_FOR_INSN", 7216 "RELOAD_FOR_INPUT_ADDRESS", 7217 "RELOAD_FOR_INPADDR_ADDRESS", 7218 "RELOAD_FOR_OUTPUT_ADDRESS", 7219 "RELOAD_FOR_OUTADDR_ADDRESS", 7220 "RELOAD_FOR_OPERAND_ADDRESS", 7221 "RELOAD_FOR_OPADDR_ADDR", 7222 "RELOAD_OTHER", 7223 "RELOAD_FOR_OTHER_ADDRESS" 7224}; 7225 7226/* These functions are used to print the variables set by 'find_reloads' */ 7227 7228void 7229debug_reload_to_stream (FILE *f) 7230{ 7231 int r; 7232 const char *prefix; 7233 7234 if (! f) 7235 f = stderr; 7236 for (r = 0; r < n_reloads; r++) 7237 { 7238 fprintf (f, "Reload %d: ", r); 7239 7240 if (rld[r].in != 0) 7241 { 7242 fprintf (f, "reload_in (%s) = ", 7243 GET_MODE_NAME (rld[r].inmode)); 7244 print_inline_rtx (f, rld[r].in, 24); 7245 fprintf (f, "\n\t"); 7246 } 7247 7248 if (rld[r].out != 0) 7249 { 7250 fprintf (f, "reload_out (%s) = ", 7251 GET_MODE_NAME (rld[r].outmode)); 7252 print_inline_rtx (f, rld[r].out, 24); 7253 fprintf (f, "\n\t"); 7254 } 7255 7256 fprintf (f, "%s, ", reg_class_names[(int) rld[r].class]); 7257 7258 fprintf (f, "%s (opnum = %d)", 7259 reload_when_needed_name[(int) rld[r].when_needed], 7260 rld[r].opnum); 7261 7262 if (rld[r].optional) 7263 fprintf (f, ", optional"); 7264 7265 if (rld[r].nongroup) 7266 fprintf (f, ", nongroup"); 7267 7268 if (rld[r].inc != 0) 7269 fprintf (f, ", inc by %d", rld[r].inc); 7270 7271 if (rld[r].nocombine) 7272 fprintf (f, ", can't combine"); 7273 7274 if (rld[r].secondary_p) 7275 fprintf (f, ", secondary_reload_p"); 7276 7277 if (rld[r].in_reg != 0) 7278 { 7279 fprintf (f, "\n\treload_in_reg: "); 7280 print_inline_rtx (f, rld[r].in_reg, 24); 7281 } 7282 7283 if (rld[r].out_reg != 0) 7284 { 7285 fprintf (f, "\n\treload_out_reg: "); 7286 print_inline_rtx (f, rld[r].out_reg, 24); 7287 } 7288 7289 if (rld[r].reg_rtx != 0) 7290 { 7291 fprintf (f, "\n\treload_reg_rtx: "); 7292 print_inline_rtx (f, rld[r].reg_rtx, 24); 7293 } 7294 7295 prefix = "\n\t"; 7296 if (rld[r].secondary_in_reload != -1) 7297 { 7298 fprintf (f, "%ssecondary_in_reload = %d", 7299 prefix, rld[r].secondary_in_reload); 7300 prefix = ", "; 7301 } 7302 7303 if (rld[r].secondary_out_reload != -1) 7304 fprintf (f, "%ssecondary_out_reload = %d\n", 7305 prefix, rld[r].secondary_out_reload); 7306 7307 prefix = "\n\t"; 7308 if (rld[r].secondary_in_icode != CODE_FOR_nothing) 7309 { 7310 fprintf (f, "%ssecondary_in_icode = %s", prefix, 7311 insn_data[rld[r].secondary_in_icode].name); 7312 prefix = ", "; 7313 } 7314 7315 if (rld[r].secondary_out_icode != CODE_FOR_nothing) 7316 fprintf (f, "%ssecondary_out_icode = %s", prefix, 7317 insn_data[rld[r].secondary_out_icode].name); 7318 7319 fprintf (f, "\n"); 7320 } 7321} 7322 7323void 7324debug_reload (void) 7325{ 7326 debug_reload_to_stream (stderr); 7327} 7328