1 /* 2 * Optimizations for Tiny Code Generator for QEMU 3 * 4 * Copyright (c) 2010 Samsung Electronics. 5 * Contributed by Kirill Batuzov <batuzovk@ispras.ru> 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a copy 8 * of this software and associated documentation files (the "Software"), to deal 9 * in the Software without restriction, including without limitation the rights 10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11 * copies of the Software, and to permit persons to whom the Software is 12 * furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice shall be included in 15 * all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 23 * THE SOFTWARE. 24 */ 25 26 #include "qemu/osdep.h" 27 #include "tcg-op.h" 28 29 #define CASE_OP_32_64(x) \ 30 glue(glue(case INDEX_op_, x), _i32): \ 31 glue(glue(case INDEX_op_, x), _i64) 32 33 #define CASE_OP_32_64_VEC(x) \ 34 glue(glue(case INDEX_op_, x), _i32): \ 35 glue(glue(case INDEX_op_, x), _i64): \ 36 glue(glue(case INDEX_op_, x), _vec) 37 38 struct tcg_temp_info { 39 bool is_const; 40 TCGTemp *prev_copy; 41 TCGTemp *next_copy; 42 tcg_target_ulong val; 43 tcg_target_ulong mask; 44 }; 45 46 static inline struct tcg_temp_info *ts_info(TCGTemp *ts) 47 { 48 return ts->state_ptr; 49 } 50 51 static inline struct tcg_temp_info *arg_info(TCGArg arg) 52 { 53 return ts_info(arg_temp(arg)); 54 } 55 56 static inline bool ts_is_const(TCGTemp *ts) 57 { 58 return ts_info(ts)->is_const; 59 } 60 61 static inline bool arg_is_const(TCGArg arg) 62 { 63 return ts_is_const(arg_temp(arg)); 64 } 65 66 static inline bool ts_is_copy(TCGTemp *ts) 67 { 68 return ts_info(ts)->next_copy != ts; 69 } 70 71 /* Reset TEMP's state, possibly removing the temp for the list of copies. */ 72 static void reset_ts(TCGTemp *ts) 73 { 74 struct tcg_temp_info *ti = ts_info(ts); 75 struct tcg_temp_info *pi = ts_info(ti->prev_copy); 76 struct tcg_temp_info *ni = ts_info(ti->next_copy); 77 78 ni->prev_copy = ti->prev_copy; 79 pi->next_copy = ti->next_copy; 80 ti->next_copy = ts; 81 ti->prev_copy = ts; 82 ti->is_const = false; 83 ti->mask = -1; 84 } 85 86 static void reset_temp(TCGArg arg) 87 { 88 reset_ts(arg_temp(arg)); 89 } 90 91 /* Initialize and activate a temporary. */ 92 static void init_ts_info(struct tcg_temp_info *infos, 93 TCGTempSet *temps_used, TCGTemp *ts) 94 { 95 size_t idx = temp_idx(ts); 96 if (!test_bit(idx, temps_used->l)) { 97 struct tcg_temp_info *ti = &infos[idx]; 98 99 ts->state_ptr = ti; 100 ti->next_copy = ts; 101 ti->prev_copy = ts; 102 ti->is_const = false; 103 ti->mask = -1; 104 set_bit(idx, temps_used->l); 105 } 106 } 107 108 static void init_arg_info(struct tcg_temp_info *infos, 109 TCGTempSet *temps_used, TCGArg arg) 110 { 111 init_ts_info(infos, temps_used, arg_temp(arg)); 112 } 113 114 static TCGTemp *find_better_copy(TCGContext *s, TCGTemp *ts) 115 { 116 TCGTemp *i; 117 118 /* If this is already a global, we can't do better. */ 119 if (ts->temp_global) { 120 return ts; 121 } 122 123 /* Search for a global first. */ 124 for (i = ts_info(ts)->next_copy; i != ts; i = ts_info(i)->next_copy) { 125 if (i->temp_global) { 126 return i; 127 } 128 } 129 130 /* If it is a temp, search for a temp local. */ 131 if (!ts->temp_local) { 132 for (i = ts_info(ts)->next_copy; i != ts; i = ts_info(i)->next_copy) { 133 if (ts->temp_local) { 134 return i; 135 } 136 } 137 } 138 139 /* Failure to find a better representation, return the same temp. */ 140 return ts; 141 } 142 143 static bool ts_are_copies(TCGTemp *ts1, TCGTemp *ts2) 144 { 145 TCGTemp *i; 146 147 if (ts1 == ts2) { 148 return true; 149 } 150 151 if (!ts_is_copy(ts1) || !ts_is_copy(ts2)) { 152 return false; 153 } 154 155 for (i = ts_info(ts1)->next_copy; i != ts1; i = ts_info(i)->next_copy) { 156 if (i == ts2) { 157 return true; 158 } 159 } 160 161 return false; 162 } 163 164 static bool args_are_copies(TCGArg arg1, TCGArg arg2) 165 { 166 return ts_are_copies(arg_temp(arg1), arg_temp(arg2)); 167 } 168 169 static void tcg_opt_gen_movi(TCGContext *s, TCGOp *op, TCGArg dst, TCGArg val) 170 { 171 const TCGOpDef *def; 172 TCGOpcode new_op; 173 tcg_target_ulong mask; 174 struct tcg_temp_info *di = arg_info(dst); 175 176 def = &tcg_op_defs[op->opc]; 177 if (def->flags & TCG_OPF_VECTOR) { 178 new_op = INDEX_op_dupi_vec; 179 } else if (def->flags & TCG_OPF_64BIT) { 180 new_op = INDEX_op_movi_i64; 181 } else { 182 new_op = INDEX_op_movi_i32; 183 } 184 op->opc = new_op; 185 /* TCGOP_VECL and TCGOP_VECE remain unchanged. */ 186 op->args[0] = dst; 187 op->args[1] = val; 188 189 reset_temp(dst); 190 di->is_const = true; 191 di->val = val; 192 mask = val; 193 if (TCG_TARGET_REG_BITS > 32 && new_op == INDEX_op_movi_i32) { 194 /* High bits of the destination are now garbage. */ 195 mask |= ~0xffffffffull; 196 } 197 di->mask = mask; 198 } 199 200 static void tcg_opt_gen_mov(TCGContext *s, TCGOp *op, TCGArg dst, TCGArg src) 201 { 202 TCGTemp *dst_ts = arg_temp(dst); 203 TCGTemp *src_ts = arg_temp(src); 204 const TCGOpDef *def; 205 struct tcg_temp_info *di; 206 struct tcg_temp_info *si; 207 tcg_target_ulong mask; 208 TCGOpcode new_op; 209 210 if (ts_are_copies(dst_ts, src_ts)) { 211 tcg_op_remove(s, op); 212 return; 213 } 214 215 reset_ts(dst_ts); 216 di = ts_info(dst_ts); 217 si = ts_info(src_ts); 218 def = &tcg_op_defs[op->opc]; 219 if (def->flags & TCG_OPF_VECTOR) { 220 new_op = INDEX_op_mov_vec; 221 } else if (def->flags & TCG_OPF_64BIT) { 222 new_op = INDEX_op_mov_i64; 223 } else { 224 new_op = INDEX_op_mov_i32; 225 } 226 op->opc = new_op; 227 /* TCGOP_VECL and TCGOP_VECE remain unchanged. */ 228 op->args[0] = dst; 229 op->args[1] = src; 230 231 mask = si->mask; 232 if (TCG_TARGET_REG_BITS > 32 && new_op == INDEX_op_mov_i32) { 233 /* High bits of the destination are now garbage. */ 234 mask |= ~0xffffffffull; 235 } 236 di->mask = mask; 237 238 if (src_ts->type == dst_ts->type) { 239 struct tcg_temp_info *ni = ts_info(si->next_copy); 240 241 di->next_copy = si->next_copy; 242 di->prev_copy = src_ts; 243 ni->prev_copy = dst_ts; 244 si->next_copy = dst_ts; 245 di->is_const = si->is_const; 246 di->val = si->val; 247 } 248 } 249 250 static TCGArg do_constant_folding_2(TCGOpcode op, TCGArg x, TCGArg y) 251 { 252 uint64_t l64, h64; 253 254 switch (op) { 255 CASE_OP_32_64(add): 256 return x + y; 257 258 CASE_OP_32_64(sub): 259 return x - y; 260 261 CASE_OP_32_64(mul): 262 return x * y; 263 264 CASE_OP_32_64(and): 265 return x & y; 266 267 CASE_OP_32_64(or): 268 return x | y; 269 270 CASE_OP_32_64(xor): 271 return x ^ y; 272 273 case INDEX_op_shl_i32: 274 return (uint32_t)x << (y & 31); 275 276 case INDEX_op_shl_i64: 277 return (uint64_t)x << (y & 63); 278 279 case INDEX_op_shr_i32: 280 return (uint32_t)x >> (y & 31); 281 282 case INDEX_op_shr_i64: 283 return (uint64_t)x >> (y & 63); 284 285 case INDEX_op_sar_i32: 286 return (int32_t)x >> (y & 31); 287 288 case INDEX_op_sar_i64: 289 return (int64_t)x >> (y & 63); 290 291 case INDEX_op_rotr_i32: 292 return ror32(x, y & 31); 293 294 case INDEX_op_rotr_i64: 295 return ror64(x, y & 63); 296 297 case INDEX_op_rotl_i32: 298 return rol32(x, y & 31); 299 300 case INDEX_op_rotl_i64: 301 return rol64(x, y & 63); 302 303 CASE_OP_32_64(not): 304 return ~x; 305 306 CASE_OP_32_64(neg): 307 return -x; 308 309 CASE_OP_32_64(andc): 310 return x & ~y; 311 312 CASE_OP_32_64(orc): 313 return x | ~y; 314 315 CASE_OP_32_64(eqv): 316 return ~(x ^ y); 317 318 CASE_OP_32_64(nand): 319 return ~(x & y); 320 321 CASE_OP_32_64(nor): 322 return ~(x | y); 323 324 case INDEX_op_clz_i32: 325 return (uint32_t)x ? clz32(x) : y; 326 327 case INDEX_op_clz_i64: 328 return x ? clz64(x) : y; 329 330 case INDEX_op_ctz_i32: 331 return (uint32_t)x ? ctz32(x) : y; 332 333 case INDEX_op_ctz_i64: 334 return x ? ctz64(x) : y; 335 336 case INDEX_op_ctpop_i32: 337 return ctpop32(x); 338 339 case INDEX_op_ctpop_i64: 340 return ctpop64(x); 341 342 CASE_OP_32_64(ext8s): 343 return (int8_t)x; 344 345 CASE_OP_32_64(ext16s): 346 return (int16_t)x; 347 348 CASE_OP_32_64(ext8u): 349 return (uint8_t)x; 350 351 CASE_OP_32_64(ext16u): 352 return (uint16_t)x; 353 354 CASE_OP_32_64(bswap16): 355 return bswap16(x); 356 357 CASE_OP_32_64(bswap32): 358 return bswap32(x); 359 360 case INDEX_op_bswap64_i64: 361 return bswap64(x); 362 363 case INDEX_op_ext_i32_i64: 364 case INDEX_op_ext32s_i64: 365 return (int32_t)x; 366 367 case INDEX_op_extu_i32_i64: 368 case INDEX_op_extrl_i64_i32: 369 case INDEX_op_ext32u_i64: 370 return (uint32_t)x; 371 372 case INDEX_op_extrh_i64_i32: 373 return (uint64_t)x >> 32; 374 375 case INDEX_op_muluh_i32: 376 return ((uint64_t)(uint32_t)x * (uint32_t)y) >> 32; 377 case INDEX_op_mulsh_i32: 378 return ((int64_t)(int32_t)x * (int32_t)y) >> 32; 379 380 case INDEX_op_muluh_i64: 381 mulu64(&l64, &h64, x, y); 382 return h64; 383 case INDEX_op_mulsh_i64: 384 muls64(&l64, &h64, x, y); 385 return h64; 386 387 case INDEX_op_div_i32: 388 /* Avoid crashing on divide by zero, otherwise undefined. */ 389 return (int32_t)x / ((int32_t)y ? : 1); 390 case INDEX_op_divu_i32: 391 return (uint32_t)x / ((uint32_t)y ? : 1); 392 case INDEX_op_div_i64: 393 return (int64_t)x / ((int64_t)y ? : 1); 394 case INDEX_op_divu_i64: 395 return (uint64_t)x / ((uint64_t)y ? : 1); 396 397 case INDEX_op_rem_i32: 398 return (int32_t)x % ((int32_t)y ? : 1); 399 case INDEX_op_remu_i32: 400 return (uint32_t)x % ((uint32_t)y ? : 1); 401 case INDEX_op_rem_i64: 402 return (int64_t)x % ((int64_t)y ? : 1); 403 case INDEX_op_remu_i64: 404 return (uint64_t)x % ((uint64_t)y ? : 1); 405 406 default: 407 fprintf(stderr, 408 "Unrecognized operation %d in do_constant_folding.\n", op); 409 tcg_abort(); 410 } 411 } 412 413 static TCGArg do_constant_folding(TCGOpcode op, TCGArg x, TCGArg y) 414 { 415 const TCGOpDef *def = &tcg_op_defs[op]; 416 TCGArg res = do_constant_folding_2(op, x, y); 417 if (!(def->flags & TCG_OPF_64BIT)) { 418 res = (int32_t)res; 419 } 420 return res; 421 } 422 423 static bool do_constant_folding_cond_32(uint32_t x, uint32_t y, TCGCond c) 424 { 425 switch (c) { 426 case TCG_COND_EQ: 427 return x == y; 428 case TCG_COND_NE: 429 return x != y; 430 case TCG_COND_LT: 431 return (int32_t)x < (int32_t)y; 432 case TCG_COND_GE: 433 return (int32_t)x >= (int32_t)y; 434 case TCG_COND_LE: 435 return (int32_t)x <= (int32_t)y; 436 case TCG_COND_GT: 437 return (int32_t)x > (int32_t)y; 438 case TCG_COND_LTU: 439 return x < y; 440 case TCG_COND_GEU: 441 return x >= y; 442 case TCG_COND_LEU: 443 return x <= y; 444 case TCG_COND_GTU: 445 return x > y; 446 default: 447 tcg_abort(); 448 } 449 } 450 451 static bool do_constant_folding_cond_64(uint64_t x, uint64_t y, TCGCond c) 452 { 453 switch (c) { 454 case TCG_COND_EQ: 455 return x == y; 456 case TCG_COND_NE: 457 return x != y; 458 case TCG_COND_LT: 459 return (int64_t)x < (int64_t)y; 460 case TCG_COND_GE: 461 return (int64_t)x >= (int64_t)y; 462 case TCG_COND_LE: 463 return (int64_t)x <= (int64_t)y; 464 case TCG_COND_GT: 465 return (int64_t)x > (int64_t)y; 466 case TCG_COND_LTU: 467 return x < y; 468 case TCG_COND_GEU: 469 return x >= y; 470 case TCG_COND_LEU: 471 return x <= y; 472 case TCG_COND_GTU: 473 return x > y; 474 default: 475 tcg_abort(); 476 } 477 } 478 479 static bool do_constant_folding_cond_eq(TCGCond c) 480 { 481 switch (c) { 482 case TCG_COND_GT: 483 case TCG_COND_LTU: 484 case TCG_COND_LT: 485 case TCG_COND_GTU: 486 case TCG_COND_NE: 487 return 0; 488 case TCG_COND_GE: 489 case TCG_COND_GEU: 490 case TCG_COND_LE: 491 case TCG_COND_LEU: 492 case TCG_COND_EQ: 493 return 1; 494 default: 495 tcg_abort(); 496 } 497 } 498 499 /* Return 2 if the condition can't be simplified, and the result 500 of the condition (0 or 1) if it can */ 501 static TCGArg do_constant_folding_cond(TCGOpcode op, TCGArg x, 502 TCGArg y, TCGCond c) 503 { 504 tcg_target_ulong xv = arg_info(x)->val; 505 tcg_target_ulong yv = arg_info(y)->val; 506 if (arg_is_const(x) && arg_is_const(y)) { 507 const TCGOpDef *def = &tcg_op_defs[op]; 508 tcg_debug_assert(!(def->flags & TCG_OPF_VECTOR)); 509 if (def->flags & TCG_OPF_64BIT) { 510 return do_constant_folding_cond_64(xv, yv, c); 511 } else { 512 return do_constant_folding_cond_32(xv, yv, c); 513 } 514 } else if (args_are_copies(x, y)) { 515 return do_constant_folding_cond_eq(c); 516 } else if (arg_is_const(y) && yv == 0) { 517 switch (c) { 518 case TCG_COND_LTU: 519 return 0; 520 case TCG_COND_GEU: 521 return 1; 522 default: 523 return 2; 524 } 525 } 526 return 2; 527 } 528 529 /* Return 2 if the condition can't be simplified, and the result 530 of the condition (0 or 1) if it can */ 531 static TCGArg do_constant_folding_cond2(TCGArg *p1, TCGArg *p2, TCGCond c) 532 { 533 TCGArg al = p1[0], ah = p1[1]; 534 TCGArg bl = p2[0], bh = p2[1]; 535 536 if (arg_is_const(bl) && arg_is_const(bh)) { 537 tcg_target_ulong blv = arg_info(bl)->val; 538 tcg_target_ulong bhv = arg_info(bh)->val; 539 uint64_t b = deposit64(blv, 32, 32, bhv); 540 541 if (arg_is_const(al) && arg_is_const(ah)) { 542 tcg_target_ulong alv = arg_info(al)->val; 543 tcg_target_ulong ahv = arg_info(ah)->val; 544 uint64_t a = deposit64(alv, 32, 32, ahv); 545 return do_constant_folding_cond_64(a, b, c); 546 } 547 if (b == 0) { 548 switch (c) { 549 case TCG_COND_LTU: 550 return 0; 551 case TCG_COND_GEU: 552 return 1; 553 default: 554 break; 555 } 556 } 557 } 558 if (args_are_copies(al, bl) && args_are_copies(ah, bh)) { 559 return do_constant_folding_cond_eq(c); 560 } 561 return 2; 562 } 563 564 static bool swap_commutative(TCGArg dest, TCGArg *p1, TCGArg *p2) 565 { 566 TCGArg a1 = *p1, a2 = *p2; 567 int sum = 0; 568 sum += arg_is_const(a1); 569 sum -= arg_is_const(a2); 570 571 /* Prefer the constant in second argument, and then the form 572 op a, a, b, which is better handled on non-RISC hosts. */ 573 if (sum > 0 || (sum == 0 && dest == a2)) { 574 *p1 = a2; 575 *p2 = a1; 576 return true; 577 } 578 return false; 579 } 580 581 static bool swap_commutative2(TCGArg *p1, TCGArg *p2) 582 { 583 int sum = 0; 584 sum += arg_is_const(p1[0]); 585 sum += arg_is_const(p1[1]); 586 sum -= arg_is_const(p2[0]); 587 sum -= arg_is_const(p2[1]); 588 if (sum > 0) { 589 TCGArg t; 590 t = p1[0], p1[0] = p2[0], p2[0] = t; 591 t = p1[1], p1[1] = p2[1], p2[1] = t; 592 return true; 593 } 594 return false; 595 } 596 597 /* Propagate constants and copies, fold constant expressions. */ 598 void tcg_optimize(TCGContext *s) 599 { 600 int nb_temps, nb_globals; 601 TCGOp *op, *op_next, *prev_mb = NULL; 602 struct tcg_temp_info *infos; 603 TCGTempSet temps_used; 604 605 /* Array VALS has an element for each temp. 606 If this temp holds a constant then its value is kept in VALS' element. 607 If this temp is a copy of other ones then the other copies are 608 available through the doubly linked circular list. */ 609 610 nb_temps = s->nb_temps; 611 nb_globals = s->nb_globals; 612 bitmap_zero(temps_used.l, nb_temps); 613 infos = tcg_malloc(sizeof(struct tcg_temp_info) * nb_temps); 614 615 QTAILQ_FOREACH_SAFE(op, &s->ops, link, op_next) { 616 tcg_target_ulong mask, partmask, affected; 617 int nb_oargs, nb_iargs, i; 618 TCGArg tmp; 619 TCGOpcode opc = op->opc; 620 const TCGOpDef *def = &tcg_op_defs[opc]; 621 622 /* Count the arguments, and initialize the temps that are 623 going to be used */ 624 if (opc == INDEX_op_call) { 625 nb_oargs = TCGOP_CALLO(op); 626 nb_iargs = TCGOP_CALLI(op); 627 for (i = 0; i < nb_oargs + nb_iargs; i++) { 628 TCGTemp *ts = arg_temp(op->args[i]); 629 if (ts) { 630 init_ts_info(infos, &temps_used, ts); 631 } 632 } 633 } else { 634 nb_oargs = def->nb_oargs; 635 nb_iargs = def->nb_iargs; 636 for (i = 0; i < nb_oargs + nb_iargs; i++) { 637 init_arg_info(infos, &temps_used, op->args[i]); 638 } 639 } 640 641 /* Do copy propagation */ 642 for (i = nb_oargs; i < nb_oargs + nb_iargs; i++) { 643 TCGTemp *ts = arg_temp(op->args[i]); 644 if (ts && ts_is_copy(ts)) { 645 op->args[i] = temp_arg(find_better_copy(s, ts)); 646 } 647 } 648 649 /* For commutative operations make constant second argument */ 650 switch (opc) { 651 CASE_OP_32_64_VEC(add): 652 CASE_OP_32_64_VEC(mul): 653 CASE_OP_32_64_VEC(and): 654 CASE_OP_32_64_VEC(or): 655 CASE_OP_32_64_VEC(xor): 656 CASE_OP_32_64(eqv): 657 CASE_OP_32_64(nand): 658 CASE_OP_32_64(nor): 659 CASE_OP_32_64(muluh): 660 CASE_OP_32_64(mulsh): 661 swap_commutative(op->args[0], &op->args[1], &op->args[2]); 662 break; 663 CASE_OP_32_64(brcond): 664 if (swap_commutative(-1, &op->args[0], &op->args[1])) { 665 op->args[2] = tcg_swap_cond(op->args[2]); 666 } 667 break; 668 CASE_OP_32_64(setcond): 669 if (swap_commutative(op->args[0], &op->args[1], &op->args[2])) { 670 op->args[3] = tcg_swap_cond(op->args[3]); 671 } 672 break; 673 CASE_OP_32_64(movcond): 674 if (swap_commutative(-1, &op->args[1], &op->args[2])) { 675 op->args[5] = tcg_swap_cond(op->args[5]); 676 } 677 /* For movcond, we canonicalize the "false" input reg to match 678 the destination reg so that the tcg backend can implement 679 a "move if true" operation. */ 680 if (swap_commutative(op->args[0], &op->args[4], &op->args[3])) { 681 op->args[5] = tcg_invert_cond(op->args[5]); 682 } 683 break; 684 CASE_OP_32_64(add2): 685 swap_commutative(op->args[0], &op->args[2], &op->args[4]); 686 swap_commutative(op->args[1], &op->args[3], &op->args[5]); 687 break; 688 CASE_OP_32_64(mulu2): 689 CASE_OP_32_64(muls2): 690 swap_commutative(op->args[0], &op->args[2], &op->args[3]); 691 break; 692 case INDEX_op_brcond2_i32: 693 if (swap_commutative2(&op->args[0], &op->args[2])) { 694 op->args[4] = tcg_swap_cond(op->args[4]); 695 } 696 break; 697 case INDEX_op_setcond2_i32: 698 if (swap_commutative2(&op->args[1], &op->args[3])) { 699 op->args[5] = tcg_swap_cond(op->args[5]); 700 } 701 break; 702 default: 703 break; 704 } 705 706 /* Simplify expressions for "shift/rot r, 0, a => movi r, 0", 707 and "sub r, 0, a => neg r, a" case. */ 708 switch (opc) { 709 CASE_OP_32_64(shl): 710 CASE_OP_32_64(shr): 711 CASE_OP_32_64(sar): 712 CASE_OP_32_64(rotl): 713 CASE_OP_32_64(rotr): 714 if (arg_is_const(op->args[1]) 715 && arg_info(op->args[1])->val == 0) { 716 tcg_opt_gen_movi(s, op, op->args[0], 0); 717 continue; 718 } 719 break; 720 CASE_OP_32_64_VEC(sub): 721 { 722 TCGOpcode neg_op; 723 bool have_neg; 724 725 if (arg_is_const(op->args[2])) { 726 /* Proceed with possible constant folding. */ 727 break; 728 } 729 if (opc == INDEX_op_sub_i32) { 730 neg_op = INDEX_op_neg_i32; 731 have_neg = TCG_TARGET_HAS_neg_i32; 732 } else if (opc == INDEX_op_sub_i64) { 733 neg_op = INDEX_op_neg_i64; 734 have_neg = TCG_TARGET_HAS_neg_i64; 735 } else if (TCG_TARGET_HAS_neg_vec) { 736 TCGType type = TCGOP_VECL(op) + TCG_TYPE_V64; 737 unsigned vece = TCGOP_VECE(op); 738 neg_op = INDEX_op_neg_vec; 739 have_neg = tcg_can_emit_vec_op(neg_op, type, vece) > 0; 740 } else { 741 break; 742 } 743 if (!have_neg) { 744 break; 745 } 746 if (arg_is_const(op->args[1]) 747 && arg_info(op->args[1])->val == 0) { 748 op->opc = neg_op; 749 reset_temp(op->args[0]); 750 op->args[1] = op->args[2]; 751 continue; 752 } 753 } 754 break; 755 CASE_OP_32_64_VEC(xor): 756 CASE_OP_32_64(nand): 757 if (!arg_is_const(op->args[1]) 758 && arg_is_const(op->args[2]) 759 && arg_info(op->args[2])->val == -1) { 760 i = 1; 761 goto try_not; 762 } 763 break; 764 CASE_OP_32_64(nor): 765 if (!arg_is_const(op->args[1]) 766 && arg_is_const(op->args[2]) 767 && arg_info(op->args[2])->val == 0) { 768 i = 1; 769 goto try_not; 770 } 771 break; 772 CASE_OP_32_64_VEC(andc): 773 if (!arg_is_const(op->args[2]) 774 && arg_is_const(op->args[1]) 775 && arg_info(op->args[1])->val == -1) { 776 i = 2; 777 goto try_not; 778 } 779 break; 780 CASE_OP_32_64_VEC(orc): 781 CASE_OP_32_64(eqv): 782 if (!arg_is_const(op->args[2]) 783 && arg_is_const(op->args[1]) 784 && arg_info(op->args[1])->val == 0) { 785 i = 2; 786 goto try_not; 787 } 788 break; 789 try_not: 790 { 791 TCGOpcode not_op; 792 bool have_not; 793 794 if (def->flags & TCG_OPF_VECTOR) { 795 not_op = INDEX_op_not_vec; 796 have_not = TCG_TARGET_HAS_not_vec; 797 } else if (def->flags & TCG_OPF_64BIT) { 798 not_op = INDEX_op_not_i64; 799 have_not = TCG_TARGET_HAS_not_i64; 800 } else { 801 not_op = INDEX_op_not_i32; 802 have_not = TCG_TARGET_HAS_not_i32; 803 } 804 if (!have_not) { 805 break; 806 } 807 op->opc = not_op; 808 reset_temp(op->args[0]); 809 op->args[1] = op->args[i]; 810 continue; 811 } 812 default: 813 break; 814 } 815 816 /* Simplify expression for "op r, a, const => mov r, a" cases */ 817 switch (opc) { 818 CASE_OP_32_64_VEC(add): 819 CASE_OP_32_64_VEC(sub): 820 CASE_OP_32_64_VEC(or): 821 CASE_OP_32_64_VEC(xor): 822 CASE_OP_32_64_VEC(andc): 823 CASE_OP_32_64(shl): 824 CASE_OP_32_64(shr): 825 CASE_OP_32_64(sar): 826 CASE_OP_32_64(rotl): 827 CASE_OP_32_64(rotr): 828 if (!arg_is_const(op->args[1]) 829 && arg_is_const(op->args[2]) 830 && arg_info(op->args[2])->val == 0) { 831 tcg_opt_gen_mov(s, op, op->args[0], op->args[1]); 832 continue; 833 } 834 break; 835 CASE_OP_32_64_VEC(and): 836 CASE_OP_32_64_VEC(orc): 837 CASE_OP_32_64(eqv): 838 if (!arg_is_const(op->args[1]) 839 && arg_is_const(op->args[2]) 840 && arg_info(op->args[2])->val == -1) { 841 tcg_opt_gen_mov(s, op, op->args[0], op->args[1]); 842 continue; 843 } 844 break; 845 default: 846 break; 847 } 848 849 /* Simplify using known-zero bits. Currently only ops with a single 850 output argument is supported. */ 851 mask = -1; 852 affected = -1; 853 switch (opc) { 854 CASE_OP_32_64(ext8s): 855 if ((arg_info(op->args[1])->mask & 0x80) != 0) { 856 break; 857 } 858 CASE_OP_32_64(ext8u): 859 mask = 0xff; 860 goto and_const; 861 CASE_OP_32_64(ext16s): 862 if ((arg_info(op->args[1])->mask & 0x8000) != 0) { 863 break; 864 } 865 CASE_OP_32_64(ext16u): 866 mask = 0xffff; 867 goto and_const; 868 case INDEX_op_ext32s_i64: 869 if ((arg_info(op->args[1])->mask & 0x80000000) != 0) { 870 break; 871 } 872 case INDEX_op_ext32u_i64: 873 mask = 0xffffffffU; 874 goto and_const; 875 876 CASE_OP_32_64(and): 877 mask = arg_info(op->args[2])->mask; 878 if (arg_is_const(op->args[2])) { 879 and_const: 880 affected = arg_info(op->args[1])->mask & ~mask; 881 } 882 mask = arg_info(op->args[1])->mask & mask; 883 break; 884 885 case INDEX_op_ext_i32_i64: 886 if ((arg_info(op->args[1])->mask & 0x80000000) != 0) { 887 break; 888 } 889 case INDEX_op_extu_i32_i64: 890 /* We do not compute affected as it is a size changing op. */ 891 mask = (uint32_t)arg_info(op->args[1])->mask; 892 break; 893 894 CASE_OP_32_64(andc): 895 /* Known-zeros does not imply known-ones. Therefore unless 896 op->args[2] is constant, we can't infer anything from it. */ 897 if (arg_is_const(op->args[2])) { 898 mask = ~arg_info(op->args[2])->mask; 899 goto and_const; 900 } 901 /* But we certainly know nothing outside args[1] may be set. */ 902 mask = arg_info(op->args[1])->mask; 903 break; 904 905 case INDEX_op_sar_i32: 906 if (arg_is_const(op->args[2])) { 907 tmp = arg_info(op->args[2])->val & 31; 908 mask = (int32_t)arg_info(op->args[1])->mask >> tmp; 909 } 910 break; 911 case INDEX_op_sar_i64: 912 if (arg_is_const(op->args[2])) { 913 tmp = arg_info(op->args[2])->val & 63; 914 mask = (int64_t)arg_info(op->args[1])->mask >> tmp; 915 } 916 break; 917 918 case INDEX_op_shr_i32: 919 if (arg_is_const(op->args[2])) { 920 tmp = arg_info(op->args[2])->val & 31; 921 mask = (uint32_t)arg_info(op->args[1])->mask >> tmp; 922 } 923 break; 924 case INDEX_op_shr_i64: 925 if (arg_is_const(op->args[2])) { 926 tmp = arg_info(op->args[2])->val & 63; 927 mask = (uint64_t)arg_info(op->args[1])->mask >> tmp; 928 } 929 break; 930 931 case INDEX_op_extrl_i64_i32: 932 mask = (uint32_t)arg_info(op->args[1])->mask; 933 break; 934 case INDEX_op_extrh_i64_i32: 935 mask = (uint64_t)arg_info(op->args[1])->mask >> 32; 936 break; 937 938 CASE_OP_32_64(shl): 939 if (arg_is_const(op->args[2])) { 940 tmp = arg_info(op->args[2])->val & (TCG_TARGET_REG_BITS - 1); 941 mask = arg_info(op->args[1])->mask << tmp; 942 } 943 break; 944 945 CASE_OP_32_64(neg): 946 /* Set to 1 all bits to the left of the rightmost. */ 947 mask = -(arg_info(op->args[1])->mask 948 & -arg_info(op->args[1])->mask); 949 break; 950 951 CASE_OP_32_64(deposit): 952 mask = deposit64(arg_info(op->args[1])->mask, 953 op->args[3], op->args[4], 954 arg_info(op->args[2])->mask); 955 break; 956 957 CASE_OP_32_64(extract): 958 mask = extract64(arg_info(op->args[1])->mask, 959 op->args[2], op->args[3]); 960 if (op->args[2] == 0) { 961 affected = arg_info(op->args[1])->mask & ~mask; 962 } 963 break; 964 CASE_OP_32_64(sextract): 965 mask = sextract64(arg_info(op->args[1])->mask, 966 op->args[2], op->args[3]); 967 if (op->args[2] == 0 && (tcg_target_long)mask >= 0) { 968 affected = arg_info(op->args[1])->mask & ~mask; 969 } 970 break; 971 972 CASE_OP_32_64(or): 973 CASE_OP_32_64(xor): 974 mask = arg_info(op->args[1])->mask | arg_info(op->args[2])->mask; 975 break; 976 977 case INDEX_op_clz_i32: 978 case INDEX_op_ctz_i32: 979 mask = arg_info(op->args[2])->mask | 31; 980 break; 981 982 case INDEX_op_clz_i64: 983 case INDEX_op_ctz_i64: 984 mask = arg_info(op->args[2])->mask | 63; 985 break; 986 987 case INDEX_op_ctpop_i32: 988 mask = 32 | 31; 989 break; 990 case INDEX_op_ctpop_i64: 991 mask = 64 | 63; 992 break; 993 994 CASE_OP_32_64(setcond): 995 case INDEX_op_setcond2_i32: 996 mask = 1; 997 break; 998 999 CASE_OP_32_64(movcond): 1000 mask = arg_info(op->args[3])->mask | arg_info(op->args[4])->mask; 1001 break; 1002 1003 CASE_OP_32_64(ld8u): 1004 mask = 0xff; 1005 break; 1006 CASE_OP_32_64(ld16u): 1007 mask = 0xffff; 1008 break; 1009 case INDEX_op_ld32u_i64: 1010 mask = 0xffffffffu; 1011 break; 1012 1013 CASE_OP_32_64(qemu_ld): 1014 { 1015 TCGMemOpIdx oi = op->args[nb_oargs + nb_iargs]; 1016 MemOp mop = get_memop(oi); 1017 if (!(mop & MO_SIGN)) { 1018 mask = (2ULL << ((8 << (mop & MO_SIZE)) - 1)) - 1; 1019 } 1020 } 1021 break; 1022 1023 default: 1024 break; 1025 } 1026 1027 /* 32-bit ops generate 32-bit results. For the result is zero test 1028 below, we can ignore high bits, but for further optimizations we 1029 need to record that the high bits contain garbage. */ 1030 partmask = mask; 1031 if (!(def->flags & TCG_OPF_64BIT)) { 1032 mask |= ~(tcg_target_ulong)0xffffffffu; 1033 partmask &= 0xffffffffu; 1034 affected &= 0xffffffffu; 1035 } 1036 1037 if (partmask == 0) { 1038 tcg_debug_assert(nb_oargs == 1); 1039 tcg_opt_gen_movi(s, op, op->args[0], 0); 1040 continue; 1041 } 1042 if (affected == 0) { 1043 tcg_debug_assert(nb_oargs == 1); 1044 tcg_opt_gen_mov(s, op, op->args[0], op->args[1]); 1045 continue; 1046 } 1047 1048 /* Simplify expression for "op r, a, 0 => movi r, 0" cases */ 1049 switch (opc) { 1050 CASE_OP_32_64_VEC(and): 1051 CASE_OP_32_64_VEC(mul): 1052 CASE_OP_32_64(muluh): 1053 CASE_OP_32_64(mulsh): 1054 if (arg_is_const(op->args[2]) 1055 && arg_info(op->args[2])->val == 0) { 1056 tcg_opt_gen_movi(s, op, op->args[0], 0); 1057 continue; 1058 } 1059 break; 1060 default: 1061 break; 1062 } 1063 1064 /* Simplify expression for "op r, a, a => mov r, a" cases */ 1065 switch (opc) { 1066 CASE_OP_32_64_VEC(or): 1067 CASE_OP_32_64_VEC(and): 1068 if (args_are_copies(op->args[1], op->args[2])) { 1069 tcg_opt_gen_mov(s, op, op->args[0], op->args[1]); 1070 continue; 1071 } 1072 break; 1073 default: 1074 break; 1075 } 1076 1077 /* Simplify expression for "op r, a, a => movi r, 0" cases */ 1078 switch (opc) { 1079 CASE_OP_32_64_VEC(andc): 1080 CASE_OP_32_64_VEC(sub): 1081 CASE_OP_32_64_VEC(xor): 1082 if (args_are_copies(op->args[1], op->args[2])) { 1083 tcg_opt_gen_movi(s, op, op->args[0], 0); 1084 continue; 1085 } 1086 break; 1087 default: 1088 break; 1089 } 1090 1091 /* Propagate constants through copy operations and do constant 1092 folding. Constants will be substituted to arguments by register 1093 allocator where needed and possible. Also detect copies. */ 1094 switch (opc) { 1095 CASE_OP_32_64_VEC(mov): 1096 tcg_opt_gen_mov(s, op, op->args[0], op->args[1]); 1097 break; 1098 CASE_OP_32_64(movi): 1099 case INDEX_op_dupi_vec: 1100 tcg_opt_gen_movi(s, op, op->args[0], op->args[1]); 1101 break; 1102 1103 case INDEX_op_dup_vec: 1104 if (arg_is_const(op->args[1])) { 1105 tmp = arg_info(op->args[1])->val; 1106 tmp = dup_const(TCGOP_VECE(op), tmp); 1107 tcg_opt_gen_movi(s, op, op->args[0], tmp); 1108 break; 1109 } 1110 goto do_default; 1111 1112 CASE_OP_32_64(not): 1113 CASE_OP_32_64(neg): 1114 CASE_OP_32_64(ext8s): 1115 CASE_OP_32_64(ext8u): 1116 CASE_OP_32_64(ext16s): 1117 CASE_OP_32_64(ext16u): 1118 CASE_OP_32_64(ctpop): 1119 CASE_OP_32_64(bswap16): 1120 CASE_OP_32_64(bswap32): 1121 case INDEX_op_bswap64_i64: 1122 case INDEX_op_ext32s_i64: 1123 case INDEX_op_ext32u_i64: 1124 case INDEX_op_ext_i32_i64: 1125 case INDEX_op_extu_i32_i64: 1126 case INDEX_op_extrl_i64_i32: 1127 case INDEX_op_extrh_i64_i32: 1128 if (arg_is_const(op->args[1])) { 1129 tmp = do_constant_folding(opc, arg_info(op->args[1])->val, 0); 1130 tcg_opt_gen_movi(s, op, op->args[0], tmp); 1131 break; 1132 } 1133 goto do_default; 1134 1135 CASE_OP_32_64(add): 1136 CASE_OP_32_64(sub): 1137 CASE_OP_32_64(mul): 1138 CASE_OP_32_64(or): 1139 CASE_OP_32_64(and): 1140 CASE_OP_32_64(xor): 1141 CASE_OP_32_64(shl): 1142 CASE_OP_32_64(shr): 1143 CASE_OP_32_64(sar): 1144 CASE_OP_32_64(rotl): 1145 CASE_OP_32_64(rotr): 1146 CASE_OP_32_64(andc): 1147 CASE_OP_32_64(orc): 1148 CASE_OP_32_64(eqv): 1149 CASE_OP_32_64(nand): 1150 CASE_OP_32_64(nor): 1151 CASE_OP_32_64(muluh): 1152 CASE_OP_32_64(mulsh): 1153 CASE_OP_32_64(div): 1154 CASE_OP_32_64(divu): 1155 CASE_OP_32_64(rem): 1156 CASE_OP_32_64(remu): 1157 if (arg_is_const(op->args[1]) && arg_is_const(op->args[2])) { 1158 tmp = do_constant_folding(opc, arg_info(op->args[1])->val, 1159 arg_info(op->args[2])->val); 1160 tcg_opt_gen_movi(s, op, op->args[0], tmp); 1161 break; 1162 } 1163 goto do_default; 1164 1165 CASE_OP_32_64(clz): 1166 CASE_OP_32_64(ctz): 1167 if (arg_is_const(op->args[1])) { 1168 TCGArg v = arg_info(op->args[1])->val; 1169 if (v != 0) { 1170 tmp = do_constant_folding(opc, v, 0); 1171 tcg_opt_gen_movi(s, op, op->args[0], tmp); 1172 } else { 1173 tcg_opt_gen_mov(s, op, op->args[0], op->args[2]); 1174 } 1175 break; 1176 } 1177 goto do_default; 1178 1179 CASE_OP_32_64(deposit): 1180 if (arg_is_const(op->args[1]) && arg_is_const(op->args[2])) { 1181 tmp = deposit64(arg_info(op->args[1])->val, 1182 op->args[3], op->args[4], 1183 arg_info(op->args[2])->val); 1184 tcg_opt_gen_movi(s, op, op->args[0], tmp); 1185 break; 1186 } 1187 goto do_default; 1188 1189 CASE_OP_32_64(extract): 1190 if (arg_is_const(op->args[1])) { 1191 tmp = extract64(arg_info(op->args[1])->val, 1192 op->args[2], op->args[3]); 1193 tcg_opt_gen_movi(s, op, op->args[0], tmp); 1194 break; 1195 } 1196 goto do_default; 1197 1198 CASE_OP_32_64(sextract): 1199 if (arg_is_const(op->args[1])) { 1200 tmp = sextract64(arg_info(op->args[1])->val, 1201 op->args[2], op->args[3]); 1202 tcg_opt_gen_movi(s, op, op->args[0], tmp); 1203 break; 1204 } 1205 goto do_default; 1206 1207 CASE_OP_32_64(extract2): 1208 if (arg_is_const(op->args[1]) && arg_is_const(op->args[2])) { 1209 TCGArg v1 = arg_info(op->args[1])->val; 1210 TCGArg v2 = arg_info(op->args[2])->val; 1211 1212 if (opc == INDEX_op_extract2_i64) { 1213 tmp = (v1 >> op->args[3]) | (v2 << (64 - op->args[3])); 1214 } else { 1215 tmp = (int32_t)(((uint32_t)v1 >> op->args[3]) | 1216 ((uint32_t)v2 << (32 - op->args[3]))); 1217 } 1218 tcg_opt_gen_movi(s, op, op->args[0], tmp); 1219 break; 1220 } 1221 goto do_default; 1222 1223 CASE_OP_32_64(setcond): 1224 tmp = do_constant_folding_cond(opc, op->args[1], 1225 op->args[2], op->args[3]); 1226 if (tmp != 2) { 1227 tcg_opt_gen_movi(s, op, op->args[0], tmp); 1228 break; 1229 } 1230 goto do_default; 1231 1232 CASE_OP_32_64(brcond): 1233 tmp = do_constant_folding_cond(opc, op->args[0], 1234 op->args[1], op->args[2]); 1235 if (tmp != 2) { 1236 if (tmp) { 1237 bitmap_zero(temps_used.l, nb_temps); 1238 op->opc = INDEX_op_br; 1239 op->args[0] = op->args[3]; 1240 } else { 1241 tcg_op_remove(s, op); 1242 } 1243 break; 1244 } 1245 goto do_default; 1246 1247 CASE_OP_32_64(movcond): 1248 tmp = do_constant_folding_cond(opc, op->args[1], 1249 op->args[2], op->args[5]); 1250 if (tmp != 2) { 1251 tcg_opt_gen_mov(s, op, op->args[0], op->args[4-tmp]); 1252 break; 1253 } 1254 if (arg_is_const(op->args[3]) && arg_is_const(op->args[4])) { 1255 tcg_target_ulong tv = arg_info(op->args[3])->val; 1256 tcg_target_ulong fv = arg_info(op->args[4])->val; 1257 TCGCond cond = op->args[5]; 1258 if (fv == 1 && tv == 0) { 1259 cond = tcg_invert_cond(cond); 1260 } else if (!(tv == 1 && fv == 0)) { 1261 goto do_default; 1262 } 1263 op->args[3] = cond; 1264 op->opc = opc = (opc == INDEX_op_movcond_i32 1265 ? INDEX_op_setcond_i32 1266 : INDEX_op_setcond_i64); 1267 nb_iargs = 2; 1268 } 1269 goto do_default; 1270 1271 case INDEX_op_add2_i32: 1272 case INDEX_op_sub2_i32: 1273 if (arg_is_const(op->args[2]) && arg_is_const(op->args[3]) 1274 && arg_is_const(op->args[4]) && arg_is_const(op->args[5])) { 1275 uint32_t al = arg_info(op->args[2])->val; 1276 uint32_t ah = arg_info(op->args[3])->val; 1277 uint32_t bl = arg_info(op->args[4])->val; 1278 uint32_t bh = arg_info(op->args[5])->val; 1279 uint64_t a = ((uint64_t)ah << 32) | al; 1280 uint64_t b = ((uint64_t)bh << 32) | bl; 1281 TCGArg rl, rh; 1282 TCGOp *op2 = tcg_op_insert_before(s, op, INDEX_op_movi_i32); 1283 1284 if (opc == INDEX_op_add2_i32) { 1285 a += b; 1286 } else { 1287 a -= b; 1288 } 1289 1290 rl = op->args[0]; 1291 rh = op->args[1]; 1292 tcg_opt_gen_movi(s, op, rl, (int32_t)a); 1293 tcg_opt_gen_movi(s, op2, rh, (int32_t)(a >> 32)); 1294 break; 1295 } 1296 goto do_default; 1297 1298 case INDEX_op_mulu2_i32: 1299 if (arg_is_const(op->args[2]) && arg_is_const(op->args[3])) { 1300 uint32_t a = arg_info(op->args[2])->val; 1301 uint32_t b = arg_info(op->args[3])->val; 1302 uint64_t r = (uint64_t)a * b; 1303 TCGArg rl, rh; 1304 TCGOp *op2 = tcg_op_insert_before(s, op, INDEX_op_movi_i32); 1305 1306 rl = op->args[0]; 1307 rh = op->args[1]; 1308 tcg_opt_gen_movi(s, op, rl, (int32_t)r); 1309 tcg_opt_gen_movi(s, op2, rh, (int32_t)(r >> 32)); 1310 break; 1311 } 1312 goto do_default; 1313 1314 case INDEX_op_brcond2_i32: 1315 tmp = do_constant_folding_cond2(&op->args[0], &op->args[2], 1316 op->args[4]); 1317 if (tmp != 2) { 1318 if (tmp) { 1319 do_brcond_true: 1320 bitmap_zero(temps_used.l, nb_temps); 1321 op->opc = INDEX_op_br; 1322 op->args[0] = op->args[5]; 1323 } else { 1324 do_brcond_false: 1325 tcg_op_remove(s, op); 1326 } 1327 } else if ((op->args[4] == TCG_COND_LT 1328 || op->args[4] == TCG_COND_GE) 1329 && arg_is_const(op->args[2]) 1330 && arg_info(op->args[2])->val == 0 1331 && arg_is_const(op->args[3]) 1332 && arg_info(op->args[3])->val == 0) { 1333 /* Simplify LT/GE comparisons vs zero to a single compare 1334 vs the high word of the input. */ 1335 do_brcond_high: 1336 bitmap_zero(temps_used.l, nb_temps); 1337 op->opc = INDEX_op_brcond_i32; 1338 op->args[0] = op->args[1]; 1339 op->args[1] = op->args[3]; 1340 op->args[2] = op->args[4]; 1341 op->args[3] = op->args[5]; 1342 } else if (op->args[4] == TCG_COND_EQ) { 1343 /* Simplify EQ comparisons where one of the pairs 1344 can be simplified. */ 1345 tmp = do_constant_folding_cond(INDEX_op_brcond_i32, 1346 op->args[0], op->args[2], 1347 TCG_COND_EQ); 1348 if (tmp == 0) { 1349 goto do_brcond_false; 1350 } else if (tmp == 1) { 1351 goto do_brcond_high; 1352 } 1353 tmp = do_constant_folding_cond(INDEX_op_brcond_i32, 1354 op->args[1], op->args[3], 1355 TCG_COND_EQ); 1356 if (tmp == 0) { 1357 goto do_brcond_false; 1358 } else if (tmp != 1) { 1359 goto do_default; 1360 } 1361 do_brcond_low: 1362 bitmap_zero(temps_used.l, nb_temps); 1363 op->opc = INDEX_op_brcond_i32; 1364 op->args[1] = op->args[2]; 1365 op->args[2] = op->args[4]; 1366 op->args[3] = op->args[5]; 1367 } else if (op->args[4] == TCG_COND_NE) { 1368 /* Simplify NE comparisons where one of the pairs 1369 can be simplified. */ 1370 tmp = do_constant_folding_cond(INDEX_op_brcond_i32, 1371 op->args[0], op->args[2], 1372 TCG_COND_NE); 1373 if (tmp == 0) { 1374 goto do_brcond_high; 1375 } else if (tmp == 1) { 1376 goto do_brcond_true; 1377 } 1378 tmp = do_constant_folding_cond(INDEX_op_brcond_i32, 1379 op->args[1], op->args[3], 1380 TCG_COND_NE); 1381 if (tmp == 0) { 1382 goto do_brcond_low; 1383 } else if (tmp == 1) { 1384 goto do_brcond_true; 1385 } 1386 goto do_default; 1387 } else { 1388 goto do_default; 1389 } 1390 break; 1391 1392 case INDEX_op_setcond2_i32: 1393 tmp = do_constant_folding_cond2(&op->args[1], &op->args[3], 1394 op->args[5]); 1395 if (tmp != 2) { 1396 do_setcond_const: 1397 tcg_opt_gen_movi(s, op, op->args[0], tmp); 1398 } else if ((op->args[5] == TCG_COND_LT 1399 || op->args[5] == TCG_COND_GE) 1400 && arg_is_const(op->args[3]) 1401 && arg_info(op->args[3])->val == 0 1402 && arg_is_const(op->args[4]) 1403 && arg_info(op->args[4])->val == 0) { 1404 /* Simplify LT/GE comparisons vs zero to a single compare 1405 vs the high word of the input. */ 1406 do_setcond_high: 1407 reset_temp(op->args[0]); 1408 arg_info(op->args[0])->mask = 1; 1409 op->opc = INDEX_op_setcond_i32; 1410 op->args[1] = op->args[2]; 1411 op->args[2] = op->args[4]; 1412 op->args[3] = op->args[5]; 1413 } else if (op->args[5] == TCG_COND_EQ) { 1414 /* Simplify EQ comparisons where one of the pairs 1415 can be simplified. */ 1416 tmp = do_constant_folding_cond(INDEX_op_setcond_i32, 1417 op->args[1], op->args[3], 1418 TCG_COND_EQ); 1419 if (tmp == 0) { 1420 goto do_setcond_const; 1421 } else if (tmp == 1) { 1422 goto do_setcond_high; 1423 } 1424 tmp = do_constant_folding_cond(INDEX_op_setcond_i32, 1425 op->args[2], op->args[4], 1426 TCG_COND_EQ); 1427 if (tmp == 0) { 1428 goto do_setcond_high; 1429 } else if (tmp != 1) { 1430 goto do_default; 1431 } 1432 do_setcond_low: 1433 reset_temp(op->args[0]); 1434 arg_info(op->args[0])->mask = 1; 1435 op->opc = INDEX_op_setcond_i32; 1436 op->args[2] = op->args[3]; 1437 op->args[3] = op->args[5]; 1438 } else if (op->args[5] == TCG_COND_NE) { 1439 /* Simplify NE comparisons where one of the pairs 1440 can be simplified. */ 1441 tmp = do_constant_folding_cond(INDEX_op_setcond_i32, 1442 op->args[1], op->args[3], 1443 TCG_COND_NE); 1444 if (tmp == 0) { 1445 goto do_setcond_high; 1446 } else if (tmp == 1) { 1447 goto do_setcond_const; 1448 } 1449 tmp = do_constant_folding_cond(INDEX_op_setcond_i32, 1450 op->args[2], op->args[4], 1451 TCG_COND_NE); 1452 if (tmp == 0) { 1453 goto do_setcond_low; 1454 } else if (tmp == 1) { 1455 goto do_setcond_const; 1456 } 1457 goto do_default; 1458 } else { 1459 goto do_default; 1460 } 1461 break; 1462 1463 case INDEX_op_call: 1464 if (!(op->args[nb_oargs + nb_iargs + 1] 1465 & (TCG_CALL_NO_READ_GLOBALS | TCG_CALL_NO_WRITE_GLOBALS))) { 1466 for (i = 0; i < nb_globals; i++) { 1467 if (test_bit(i, temps_used.l)) { 1468 reset_ts(&s->temps[i]); 1469 } 1470 } 1471 } 1472 goto do_reset_output; 1473 1474 default: 1475 do_default: 1476 /* Default case: we know nothing about operation (or were unable 1477 to compute the operation result) so no propagation is done. 1478 We trash everything if the operation is the end of a basic 1479 block, otherwise we only trash the output args. "mask" is 1480 the non-zero bits mask for the first output arg. */ 1481 if (def->flags & TCG_OPF_BB_END) { 1482 bitmap_zero(temps_used.l, nb_temps); 1483 } else { 1484 do_reset_output: 1485 for (i = 0; i < nb_oargs; i++) { 1486 reset_temp(op->args[i]); 1487 /* Save the corresponding known-zero bits mask for the 1488 first output argument (only one supported so far). */ 1489 if (i == 0) { 1490 arg_info(op->args[i])->mask = mask; 1491 } 1492 } 1493 } 1494 break; 1495 } 1496 1497 /* Eliminate duplicate and redundant fence instructions. */ 1498 if (prev_mb) { 1499 switch (opc) { 1500 case INDEX_op_mb: 1501 /* Merge two barriers of the same type into one, 1502 * or a weaker barrier into a stronger one, 1503 * or two weaker barriers into a stronger one. 1504 * mb X; mb Y => mb X|Y 1505 * mb; strl => mb; st 1506 * ldaq; mb => ld; mb 1507 * ldaq; strl => ld; mb; st 1508 * Other combinations are also merged into a strong 1509 * barrier. This is stricter than specified but for 1510 * the purposes of TCG is better than not optimizing. 1511 */ 1512 prev_mb->args[0] |= op->args[0]; 1513 tcg_op_remove(s, op); 1514 break; 1515 1516 default: 1517 /* Opcodes that end the block stop the optimization. */ 1518 if ((def->flags & TCG_OPF_BB_END) == 0) { 1519 break; 1520 } 1521 /* fallthru */ 1522 case INDEX_op_qemu_ld_i32: 1523 case INDEX_op_qemu_ld_i64: 1524 case INDEX_op_qemu_st_i32: 1525 case INDEX_op_qemu_st_i64: 1526 case INDEX_op_call: 1527 /* Opcodes that touch guest memory stop the optimization. */ 1528 prev_mb = NULL; 1529 break; 1530 } 1531 } else if (opc == INDEX_op_mb) { 1532 prev_mb = op; 1533 } 1534 } 1535 } 1536