tcg/optimize.c

   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
  28
  29 #include "qemu-common.h"
  30 #include "tcg-op.h"
  31
  32 #define CASE_OP_32_64(x)                        \
  33         glue(glue(case INDEX_op_, x), _i32):    \
  34         glue(glue(case INDEX_op_, x), _i64)
  35
  36 struct tcg_temp_info {
  37     bool is_const;
  38     uint16_t prev_copy;
  39     uint16_t next_copy;
  40     tcg_target_ulong val;
  41     tcg_target_ulong mask;
  42 };
  43
  44 static struct tcg_temp_info temps[TCG_MAX_TEMPS];
  45 static TCGTempSet temps_used;
  46
  47 static inline bool temp_is_const(TCGArg arg)
  48 {
  49     return temps[arg].is_const;
  50 }
  51
  52 static inline bool temp_is_copy(TCGArg arg)
  53 {
  54     return temps[arg].next_copy != arg;
  55 }
  56
  57 /* Reset TEMP's state, possibly removing the temp for the list of copies.  */
  58 static void reset_temp(TCGArg temp)
  59 {
  60     temps[temps[temp].next_copy].prev_copy = temps[temp].prev_copy;
  61     temps[temps[temp].prev_copy].next_copy = temps[temp].next_copy;
  62     temps[temp].next_copy = temp;
  63     temps[temp].prev_copy = temp;
  64     temps[temp].is_const = false;
  65     temps[temp].mask = -1;
  66 }
  67
  68 /* Reset all temporaries, given that there are NB_TEMPS of them.  */
  69 static void reset_all_temps(int nb_temps)
  70 {
  71     bitmap_zero(temps_used.l, nb_temps);
  72 }
  73
  74 /* Initialize and activate a temporary.  */
  75 static void init_temp_info(TCGArg temp)
  76 {
  77     if (!test_bit(temp, temps_used.l)) {
  78         temps[temp].next_copy = temp;
  79         temps[temp].prev_copy = temp;
  80         temps[temp].is_const = false;
  81         temps[temp].mask = -1;
  82         set_bit(temp, temps_used.l);
  83     }
  84 }
  85
  86 static TCGOp *insert_op_before(TCGContext *s, TCGOp *old_op,
  87                                 TCGOpcode opc, int nargs)
  88 {
  89     int oi = s->gen_next_op_idx;
  90     int pi = s->gen_next_parm_idx;
  91     int prev = old_op->prev;
  92     int next = old_op - s->gen_op_buf;
  93     TCGOp *new_op;
  94
  95     tcg_debug_assert(oi < OPC_BUF_SIZE);
  96     tcg_debug_assert(pi + nargs <= OPPARAM_BUF_SIZE);
  97     s->gen_next_op_idx = oi + 1;
  98     s->gen_next_parm_idx = pi + nargs;
  99
 100     new_op = &s->gen_op_buf[oi];
 101     *new_op = (TCGOp){
 102         .opc = opc,
 103         .args = pi,
 104         .prev = prev,
 105         .next = next
 106     };
 107     if (prev >= 0) {
 108         s->gen_op_buf[prev].next = oi;
 109     } else {
 110         s->gen_first_op_idx = oi;
 111     }
 112     old_op->prev = oi;
 113
 114     return new_op;
 115 }
 116
 117 static int op_bits(TCGOpcode op)
 118 {
 119     const TCGOpDef *def = &tcg_op_defs[op];
 120     return def->flags & TCG_OPF_64BIT ? 64 : 32;
 121 }
 122
 123 static TCGOpcode op_to_mov(TCGOpcode op)
 124 {
 125     switch (op_bits(op)) {
 126     case 32:
 127         return INDEX_op_mov_i32;
 128     case 64:
 129         return INDEX_op_mov_i64;
 130     default:
 131         fprintf(stderr, "op_to_mov: unexpected return value of "
 132                 "function op_bits.\n");
 133         tcg_abort();
 134     }
 135 }
 136
 137 static TCGOpcode op_to_movi(TCGOpcode op)
 138 {
 139     switch (op_bits(op)) {
 140     case 32:
 141         return INDEX_op_movi_i32;
 142     case 64:
 143         return INDEX_op_movi_i64;
 144     default:
 145         fprintf(stderr, "op_to_movi: unexpected return value of "
 146                 "function op_bits.\n");
 147         tcg_abort();
 148     }
 149 }
 150
 151 static TCGArg find_better_copy(TCGContext *s, TCGArg temp)
 152 {
 153     TCGArg i;
 154
 155     /* If this is already a global, we can't do better. */
 156     if (temp < s->nb_globals) {
 157         return temp;
 158     }
 159
 160     /* Search for a global first. */
 161     for (i = temps[temp].next_copy ; i != temp ; i = temps[i].next_copy) {
 162         if (i < s->nb_globals) {
 163             return i;
 164         }
 165     }
 166
 167     /* If it is a temp, search for a temp local. */
 168     if (!s->temps[temp].temp_local) {
 169         for (i = temps[temp].next_copy ; i != temp ; i = temps[i].next_copy) {
 170             if (s->temps[i].temp_local) {
 171                 return i;
 172             }
 173         }
 174     }
 175
 176     /* Failure to find a better representation, return the same temp. */
 177     return temp;
 178 }
 179
 180 static bool temps_are_copies(TCGArg arg1, TCGArg arg2)
 181 {
 182     TCGArg i;
 183
 184     if (arg1 == arg2) {
 185         return true;
 186     }
 187
 188     if (!temp_is_copy(arg1) || !temp_is_copy(arg2)) {
 189         return false;
 190     }
 191
 192     for (i = temps[arg1].next_copy ; i != arg1 ; i = temps[i].next_copy) {
 193         if (i == arg2) {
 194             return true;
 195         }
 196     }
 197
 198     return false;
 199 }
 200
 201 static void tcg_opt_gen_movi(TCGContext *s, TCGOp *op, TCGArg *args,
 202                              TCGArg dst, TCGArg val)
 203 {
 204     TCGOpcode new_op = op_to_movi(op->opc);
 205     tcg_target_ulong mask;
 206
 207     op->opc = new_op;
 208
 209     reset_temp(dst);
 210     temps[dst].is_const = true;
 211     temps[dst].val = val;
 212     mask = val;
 213     if (TCG_TARGET_REG_BITS > 32 && new_op == INDEX_op_movi_i32) {
 214         /* High bits of the destination are now garbage.  */
 215         mask |= ~0xffffffffull;
 216     }
 217     temps[dst].mask = mask;
 218
 219     args[0] = dst;
 220     args[1] = val;
 221 }
 222
 223 static void tcg_opt_gen_mov(TCGContext *s, TCGOp *op, TCGArg *args,
 224                             TCGArg dst, TCGArg src)
 225 {
 226     if (temps_are_copies(dst, src)) {
 227         tcg_op_remove(s, op);
 228         return;
 229     }
 230
 231     TCGOpcode new_op = op_to_mov(op->opc);
 232     tcg_target_ulong mask;
 233
 234     op->opc = new_op;
 235
 236     reset_temp(dst);
 237     mask = temps[src].mask;
 238     if (TCG_TARGET_REG_BITS > 32 && new_op == INDEX_op_mov_i32) {
 239         /* High bits of the destination are now garbage.  */
 240         mask |= ~0xffffffffull;
 241     }
 242     temps[dst].mask = mask;
 243
 244     if (s->temps[src].type == s->temps[dst].type) {
 245         temps[dst].next_copy = temps[src].next_copy;
 246         temps[dst].prev_copy = src;
 247         temps[temps[dst].next_copy].prev_copy = dst;
 248         temps[src].next_copy = dst;
 249         temps[dst].is_const = temps[src].is_const;
 250         temps[dst].val = temps[src].val;
 251     }
 252
 253     args[0] = dst;
 254     args[1] = src;
 255 }
 256
 257 static TCGArg do_constant_folding_2(TCGOpcode op, TCGArg x, TCGArg y)
 258 {
 259     uint64_t l64, h64;
 260
 261     switch (op) {
 262     CASE_OP_32_64(add):
 263         return x + y;
 264
 265     CASE_OP_32_64(sub):
 266         return x - y;
 267
 268     CASE_OP_32_64(mul):
 269         return x * y;
 270
 271     CASE_OP_32_64(and):
 272         return x & y;
 273
 274     CASE_OP_32_64(or):
 275         return x | y;
 276
 277     CASE_OP_32_64(xor):
 278         return x ^ y;
 279
 280     case INDEX_op_shl_i32:
 281         return (uint32_t)x << (y & 31);
 282
 283     case INDEX_op_shl_i64:
 284         return (uint64_t)x << (y & 63);
 285
 286     case INDEX_op_shr_i32:
 287         return (uint32_t)x >> (y & 31);
 288
 289     case INDEX_op_shr_i64:
 290         return (uint64_t)x >> (y & 63);
 291
 292     case INDEX_op_sar_i32:
 293         return (int32_t)x >> (y & 31);
 294
 295     case INDEX_op_sar_i64:
 296         return (int64_t)x >> (y & 63);
 297
 298     case INDEX_op_rotr_i32:
 299         return ror32(x, y & 31);
 300
 301     case INDEX_op_rotr_i64:
 302         return ror64(x, y & 63);
 303
 304     case INDEX_op_rotl_i32:
 305         return rol32(x, y & 31);
 306
 307     case INDEX_op_rotl_i64:
 308         return rol64(x, y & 63);
 309
 310     CASE_OP_32_64(not):
 311         return ~x;
 312
 313     CASE_OP_32_64(neg):
 314         return -x;
 315
 316     CASE_OP_32_64(andc):
 317         return x & ~y;
 318
 319     CASE_OP_32_64(orc):
 320         return x | ~y;
 321
 322     CASE_OP_32_64(eqv):
 323         return ~(x ^ y);
 324
 325     CASE_OP_32_64(nand):
 326         return ~(x & y);
 327
 328     CASE_OP_32_64(nor):
 329         return ~(x | y);
 330
 331     CASE_OP_32_64(ext8s):
 332         return (int8_t)x;
 333
 334     CASE_OP_32_64(ext16s):
 335         return (int16_t)x;
 336
 337     CASE_OP_32_64(ext8u):
 338         return (uint8_t)x;
 339
 340     CASE_OP_32_64(ext16u):
 341         return (uint16_t)x;
 342
 343     case INDEX_op_ext_i32_i64:
 344     case INDEX_op_ext32s_i64:
 345         return (int32_t)x;
 346
 347     case INDEX_op_extu_i32_i64:
 348     case INDEX_op_extrl_i64_i32:
 349     case INDEX_op_ext32u_i64:
 350         return (uint32_t)x;
 351
 352     case INDEX_op_extrh_i64_i32:
 353         return (uint64_t)x >> 32;
 354
 355     case INDEX_op_muluh_i32:
 356         return ((uint64_t)(uint32_t)x * (uint32_t)y) >> 32;
 357     case INDEX_op_mulsh_i32:
 358         return ((int64_t)(int32_t)x * (int32_t)y) >> 32;
 359
 360     case INDEX_op_muluh_i64:
 361         mulu64(&l64, &h64, x, y);
 362         return h64;
 363     case INDEX_op_mulsh_i64:
 364         muls64(&l64, &h64, x, y);
 365         return h64;
 366
 367     case INDEX_op_div_i32:
 368         /* Avoid crashing on divide by zero, otherwise undefined.  */
 369         return (int32_t)x / ((int32_t)y ? : 1);
 370     case INDEX_op_divu_i32:
 371         return (uint32_t)x / ((uint32_t)y ? : 1);
 372     case INDEX_op_div_i64:
 373         return (int64_t)x / ((int64_t)y ? : 1);
 374     case INDEX_op_divu_i64:
 375         return (uint64_t)x / ((uint64_t)y ? : 1);
 376
 377     case INDEX_op_rem_i32:
 378         return (int32_t)x % ((int32_t)y ? : 1);
 379     case INDEX_op_remu_i32:
 380         return (uint32_t)x % ((uint32_t)y ? : 1);
 381     case INDEX_op_rem_i64:
 382         return (int64_t)x % ((int64_t)y ? : 1);
 383     case INDEX_op_remu_i64:
 384         return (uint64_t)x % ((uint64_t)y ? : 1);
 385
 386     default:
 387         fprintf(stderr,
 388                 "Unrecognized operation %d in do_constant_folding.\n", op);
 389         tcg_abort();
 390     }
 391 }
 392
 393 static TCGArg do_constant_folding(TCGOpcode op, TCGArg x, TCGArg y)
 394 {
 395     TCGArg res = do_constant_folding_2(op, x, y);
 396     if (op_bits(op) == 32) {
 397         res = (int32_t)res;
 398     }
 399     return res;
 400 }
 401
 402 static bool do_constant_folding_cond_32(uint32_t x, uint32_t y, TCGCond c)
 403 {
 404     switch (c) {
 405     case TCG_COND_EQ:
 406         return x == y;
 407     case TCG_COND_NE:
 408         return x != y;
 409     case TCG_COND_LT:
 410         return (int32_t)x < (int32_t)y;
 411     case TCG_COND_GE:
 412         return (int32_t)x >= (int32_t)y;
 413     case TCG_COND_LE:
 414         return (int32_t)x <= (int32_t)y;
 415     case TCG_COND_GT:
 416         return (int32_t)x > (int32_t)y;
 417     case TCG_COND_LTU:
 418         return x < y;
 419     case TCG_COND_GEU:
 420         return x >= y;
 421     case TCG_COND_LEU:
 422         return x <= y;
 423     case TCG_COND_GTU:
 424         return x > y;
 425     default:
 426         tcg_abort();
 427     }
 428 }
 429
 430 static bool do_constant_folding_cond_64(uint64_t x, uint64_t y, TCGCond c)
 431 {
 432     switch (c) {
 433     case TCG_COND_EQ:
 434         return x == y;
 435     case TCG_COND_NE:
 436         return x != y;
 437     case TCG_COND_LT:
 438         return (int64_t)x < (int64_t)y;
 439     case TCG_COND_GE:
 440         return (int64_t)x >= (int64_t)y;
 441     case TCG_COND_LE:
 442         return (int64_t)x <= (int64_t)y;
 443     case TCG_COND_GT:
 444         return (int64_t)x > (int64_t)y;
 445     case TCG_COND_LTU:
 446         return x < y;
 447     case TCG_COND_GEU:
 448         return x >= y;
 449     case TCG_COND_LEU:
 450         return x <= y;
 451     case TCG_COND_GTU:
 452         return x > y;
 453     default:
 454         tcg_abort();
 455     }
 456 }
 457
 458 static bool do_constant_folding_cond_eq(TCGCond c)
 459 {
 460     switch (c) {
 461     case TCG_COND_GT:
 462     case TCG_COND_LTU:
 463     case TCG_COND_LT:
 464     case TCG_COND_GTU:
 465     case TCG_COND_NE:
 466         return 0;
 467     case TCG_COND_GE:
 468     case TCG_COND_GEU:
 469     case TCG_COND_LE:
 470     case TCG_COND_LEU:
 471     case TCG_COND_EQ:
 472         return 1;
 473     default:
 474         tcg_abort();
 475     }
 476 }
 477
 478 /* Return 2 if the condition can't be simplified, and the result
 479    of the condition (0 or 1) if it can */
 480 static TCGArg do_constant_folding_cond(TCGOpcode op, TCGArg x,
 481                                        TCGArg y, TCGCond c)
 482 {
 483     if (temp_is_const(x) && temp_is_const(y)) {
 484         switch (op_bits(op)) {
 485         case 32:
 486             return do_constant_folding_cond_32(temps[x].val, temps[y].val, c);
 487         case 64:
 488             return do_constant_folding_cond_64(temps[x].val, temps[y].val, c);
 489         default:
 490             tcg_abort();
 491         }
 492     } else if (temps_are_copies(x, y)) {
 493         return do_constant_folding_cond_eq(c);
 494     } else if (temp_is_const(y) && temps[y].val == 0) {
 495         switch (c) {
 496         case TCG_COND_LTU:
 497             return 0;
 498         case TCG_COND_GEU:
 499             return 1;
 500         default:
 501             return 2;
 502         }
 503     } else {
 504         return 2;
 505     }
 506 }
 507
 508 /* Return 2 if the condition can't be simplified, and the result
 509    of the condition (0 or 1) if it can */
 510 static TCGArg do_constant_folding_cond2(TCGArg *p1, TCGArg *p2, TCGCond c)
 511 {
 512     TCGArg al = p1[0], ah = p1[1];
 513     TCGArg bl = p2[0], bh = p2[1];
 514
 515     if (temp_is_const(bl) && temp_is_const(bh)) {
 516         uint64_t b = ((uint64_t)temps[bh].val << 32) | (uint32_t)temps[bl].val;
 517
 518         if (temp_is_const(al) && temp_is_const(ah)) {
 519             uint64_t a;
 520             a = ((uint64_t)temps[ah].val << 32) | (uint32_t)temps[al].val;
 521             return do_constant_folding_cond_64(a, b, c);
 522         }
 523         if (b == 0) {
 524             switch (c) {
 525             case TCG_COND_LTU:
 526                 return 0;
 527             case TCG_COND_GEU:
 528                 return 1;
 529             default:
 530                 break;
 531             }
 532         }
 533     }
 534     if (temps_are_copies(al, bl) && temps_are_copies(ah, bh)) {
 535         return do_constant_folding_cond_eq(c);
 536     }
 537     return 2;
 538 }
 539
 540 static bool swap_commutative(TCGArg dest, TCGArg *p1, TCGArg *p2)
 541 {
 542     TCGArg a1 = *p1, a2 = *p2;
 543     int sum = 0;
 544     sum += temp_is_const(a1);
 545     sum -= temp_is_const(a2);
 546
 547     /* Prefer the constant in second argument, and then the form
 548        op a, a, b, which is better handled on non-RISC hosts. */
 549     if (sum > 0 || (sum == 0 && dest == a2)) {
 550         *p1 = a2;
 551         *p2 = a1;
 552         return true;
 553     }
 554     return false;
 555 }
 556
 557 static bool swap_commutative2(TCGArg *p1, TCGArg *p2)
 558 {
 559     int sum = 0;
 560     sum += temp_is_const(p1[0]);
 561     sum += temp_is_const(p1[1]);
 562     sum -= temp_is_const(p2[0]);
 563     sum -= temp_is_const(p2[1]);
 564     if (sum > 0) {
 565         TCGArg t;
 566         t = p1[0], p1[0] = p2[0], p2[0] = t;
 567         t = p1[1], p1[1] = p2[1], p2[1] = t;
 568         return true;
 569     }
 570     return false;
 571 }
 572
 573 /* Propagate constants and copies, fold constant expressions. */
 574 void tcg_optimize(TCGContext *s)
 575 {
 576     int oi, oi_next, nb_temps, nb_globals;
 577
 578     /* Array VALS has an element for each temp.
 579        If this temp holds a constant then its value is kept in VALS' element.
 580        If this temp is a copy of other ones then the other copies are
 581        available through the doubly linked circular list. */
 582
 583     nb_temps = s->nb_temps;
 584     nb_globals = s->nb_globals;
 585     reset_all_temps(nb_temps);
 586
 587     for (oi = s->gen_first_op_idx; oi >= 0; oi = oi_next) {
 588         tcg_target_ulong mask, partmask, affected;
 589         int nb_oargs, nb_iargs, i;
 590         TCGArg tmp;
 591
 592         TCGOp * const op = &s->gen_op_buf[oi];
 593         TCGArg * const args = &s->gen_opparam_buf[op->args];
 594         TCGOpcode opc = op->opc;
 595         const TCGOpDef *def = &tcg_op_defs[opc];
 596
 597         oi_next = op->next;
 598
 599         /* Count the arguments, and initialize the temps that are
 600            going to be used */
 601         if (opc == INDEX_op_call) {
 602             nb_oargs = op->callo;
 603             nb_iargs = op->calli;
 604             for (i = 0; i < nb_oargs + nb_iargs; i++) {
 605                 tmp = args[i];
 606                 if (tmp != TCG_CALL_DUMMY_ARG) {
 607                     init_temp_info(tmp);
 608                 }
 609             }
 610         } else {
 611             nb_oargs = def->nb_oargs;
 612             nb_iargs = def->nb_iargs;
 613             for (i = 0; i < nb_oargs + nb_iargs; i++) {
 614                 init_temp_info(args[i]);
 615             }
 616         }
 617
 618         /* Do copy propagation */
 619         for (i = nb_oargs; i < nb_oargs + nb_iargs; i++) {
 620             if (temp_is_copy(args[i])) {
 621                 args[i] = find_better_copy(s, args[i]);
 622             }
 623         }
 624
 625         /* For commutative operations make constant second argument */
 626         switch (opc) {
 627         CASE_OP_32_64(add):
 628         CASE_OP_32_64(mul):
 629         CASE_OP_32_64(and):
 630         CASE_OP_32_64(or):
 631         CASE_OP_32_64(xor):
 632         CASE_OP_32_64(eqv):
 633         CASE_OP_32_64(nand):
 634         CASE_OP_32_64(nor):
 635         CASE_OP_32_64(muluh):
 636         CASE_OP_32_64(mulsh):
 637             swap_commutative(args[0], &args[1], &args[2]);
 638             break;
 639         CASE_OP_32_64(brcond):
 640             if (swap_commutative(-1, &args[0], &args[1])) {
 641                 args[2] = tcg_swap_cond(args[2]);
 642             }
 643             break;
 644         CASE_OP_32_64(setcond):
 645             if (swap_commutative(args[0], &args[1], &args[2])) {
 646                 args[3] = tcg_swap_cond(args[3]);
 647             }
 648             break;
 649         CASE_OP_32_64(movcond):
 650             if (swap_commutative(-1, &args[1], &args[2])) {
 651                 args[5] = tcg_swap_cond(args[5]);
 652             }
 653             /* For movcond, we canonicalize the "false" input reg to match
 654                the destination reg so that the tcg backend can implement
 655                a "move if true" operation.  */
 656             if (swap_commutative(args[0], &args[4], &args[3])) {
 657                 args[5] = tcg_invert_cond(args[5]);
 658             }
 659             break;
 660         CASE_OP_32_64(add2):
 661             swap_commutative(args[0], &args[2], &args[4]);
 662             swap_commutative(args[1], &args[3], &args[5]);
 663             break;
 664         CASE_OP_32_64(mulu2):
 665         CASE_OP_32_64(muls2):
 666             swap_commutative(args[0], &args[2], &args[3]);
 667             break;
 668         case INDEX_op_brcond2_i32:
 669             if (swap_commutative2(&args[0], &args[2])) {
 670                 args[4] = tcg_swap_cond(args[4]);
 671             }
 672             break;
 673         case INDEX_op_setcond2_i32:
 674             if (swap_commutative2(&args[1], &args[3])) {
 675                 args[5] = tcg_swap_cond(args[5]);
 676             }
 677             break;
 678         default:
 679             break;
 680         }
 681
 682         /* Simplify expressions for "shift/rot r, 0, a => movi r, 0",
 683            and "sub r, 0, a => neg r, a" case.  */
 684         switch (opc) {
 685         CASE_OP_32_64(shl):
 686         CASE_OP_32_64(shr):
 687         CASE_OP_32_64(sar):
 688         CASE_OP_32_64(rotl):
 689         CASE_OP_32_64(rotr):
 690             if (temp_is_const(args[1]) && temps[args[1]].val == 0) {
 691                 tcg_opt_gen_movi(s, op, args, args[0], 0);
 692                 continue;
 693             }
 694             break;
 695         CASE_OP_32_64(sub):
 696             {
 697                 TCGOpcode neg_op;
 698                 bool have_neg;
 699
 700                 if (temp_is_const(args[2])) {
 701                     /* Proceed with possible constant folding. */
 702                     break;
 703                 }
 704                 if (opc == INDEX_op_sub_i32) {
 705                     neg_op = INDEX_op_neg_i32;
 706                     have_neg = TCG_TARGET_HAS_neg_i32;
 707                 } else {
 708                     neg_op = INDEX_op_neg_i64;
 709                     have_neg = TCG_TARGET_HAS_neg_i64;
 710                 }
 711                 if (!have_neg) {
 712                     break;
 713                 }
 714                 if (temp_is_const(args[1]) && temps[args[1]].val == 0) {
 715                     op->opc = neg_op;
 716                     reset_temp(args[0]);
 717                     args[1] = args[2];
 718                     continue;
 719                 }
 720             }
 721             break;
 722         CASE_OP_32_64(xor):
 723         CASE_OP_32_64(nand):
 724             if (!temp_is_const(args[1])
 725                 && temp_is_const(args[2]) && temps[args[2]].val == -1) {
 726                 i = 1;
 727                 goto try_not;
 728             }
 729             break;
 730         CASE_OP_32_64(nor):
 731             if (!temp_is_const(args[1])
 732                 && temp_is_const(args[2]) && temps[args[2]].val == 0) {
 733                 i = 1;
 734                 goto try_not;
 735             }
 736             break;
 737         CASE_OP_32_64(andc):
 738             if (!temp_is_const(args[2])
 739                 && temp_is_const(args[1]) && temps[args[1]].val == -1) {
 740                 i = 2;
 741                 goto try_not;
 742             }
 743             break;
 744         CASE_OP_32_64(orc):
 745         CASE_OP_32_64(eqv):
 746             if (!temp_is_const(args[2])
 747                 && temp_is_const(args[1]) && temps[args[1]].val == 0) {
 748                 i = 2;
 749                 goto try_not;
 750             }
 751             break;
 752         try_not:
 753             {
 754                 TCGOpcode not_op;
 755                 bool have_not;
 756
 757                 if (def->flags & TCG_OPF_64BIT) {
 758                     not_op = INDEX_op_not_i64;
 759                     have_not = TCG_TARGET_HAS_not_i64;
 760                 } else {
 761                     not_op = INDEX_op_not_i32;
 762                     have_not = TCG_TARGET_HAS_not_i32;
 763                 }
 764                 if (!have_not) {
 765                     break;
 766                 }
 767                 op->opc = not_op;
 768                 reset_temp(args[0]);
 769                 args[1] = args[i];
 770                 continue;
 771             }
 772         default:
 773             break;
 774         }
 775
 776         /* Simplify expression for "op r, a, const => mov r, a" cases */
 777         switch (opc) {
 778         CASE_OP_32_64(add):
 779         CASE_OP_32_64(sub):
 780         CASE_OP_32_64(shl):
 781         CASE_OP_32_64(shr):
 782         CASE_OP_32_64(sar):
 783         CASE_OP_32_64(rotl):
 784         CASE_OP_32_64(rotr):
 785         CASE_OP_32_64(or):
 786         CASE_OP_32_64(xor):
 787         CASE_OP_32_64(andc):
 788             if (!temp_is_const(args[1])
 789                 && temp_is_const(args[2]) && temps[args[2]].val == 0) {
 790                 tcg_opt_gen_mov(s, op, args, args[0], args[1]);
 791                 continue;
 792             }
 793             break;
 794         CASE_OP_32_64(and):
 795         CASE_OP_32_64(orc):
 796         CASE_OP_32_64(eqv):
 797             if (!temp_is_const(args[1])
 798                 && temp_is_const(args[2]) && temps[args[2]].val == -1) {
 799                 tcg_opt_gen_mov(s, op, args, args[0], args[1]);
 800                 continue;
 801             }
 802             break;
 803         default:
 804             break;
 805         }
 806
 807         /* Simplify using known-zero bits. Currently only ops with a single
 808            output argument is supported. */
 809         mask = -1;
 810         affected = -1;
 811         switch (opc) {
 812         CASE_OP_32_64(ext8s):
 813             if ((temps[args[1]].mask & 0x80) != 0) {
 814                 break;
 815             }
 816         CASE_OP_32_64(ext8u):
 817             mask = 0xff;
 818             goto and_const;
 819         CASE_OP_32_64(ext16s):
 820             if ((temps[args[1]].mask & 0x8000) != 0) {
 821                 break;
 822             }
 823         CASE_OP_32_64(ext16u):
 824             mask = 0xffff;
 825             goto and_const;
 826         case INDEX_op_ext32s_i64:
 827             if ((temps[args[1]].mask & 0x80000000) != 0) {
 828                 break;
 829             }
 830         case INDEX_op_ext32u_i64:
 831             mask = 0xffffffffU;
 832             goto and_const;
 833
 834         CASE_OP_32_64(and):
 835             mask = temps[args[2]].mask;
 836             if (temp_is_const(args[2])) {
 837         and_const:
 838                 affected = temps[args[1]].mask & ~mask;
 839             }
 840             mask = temps[args[1]].mask & mask;
 841             break;
 842
 843         case INDEX_op_ext_i32_i64:
 844             if ((temps[args[1]].mask & 0x80000000) != 0) {
 845                 break;
 846             }
 847         case INDEX_op_extu_i32_i64:
 848             /* We do not compute affected as it is a size changing op.  */
 849             mask = (uint32_t)temps[args[1]].mask;
 850             break;
 851
 852         CASE_OP_32_64(andc):
 853             /* Known-zeros does not imply known-ones.  Therefore unless
 854                args[2] is constant, we can't infer anything from it.  */
 855             if (temp_is_const(args[2])) {
 856                 mask = ~temps[args[2]].mask;
 857                 goto and_const;
 858             }
 859             /* But we certainly know nothing outside args[1] may be set. */
 860             mask = temps[args[1]].mask;
 861             break;
 862
 863         case INDEX_op_sar_i32:
 864             if (temp_is_const(args[2])) {
 865                 tmp = temps[args[2]].val & 31;
 866                 mask = (int32_t)temps[args[1]].mask >> tmp;
 867             }
 868             break;
 869         case INDEX_op_sar_i64:
 870             if (temp_is_const(args[2])) {
 871                 tmp = temps[args[2]].val & 63;
 872                 mask = (int64_t)temps[args[1]].mask >> tmp;
 873             }
 874             break;
 875
 876         case INDEX_op_shr_i32:
 877             if (temp_is_const(args[2])) {
 878                 tmp = temps[args[2]].val & 31;
 879                 mask = (uint32_t)temps[args[1]].mask >> tmp;
 880             }
 881             break;
 882         case INDEX_op_shr_i64:
 883             if (temp_is_const(args[2])) {
 884                 tmp = temps[args[2]].val & 63;
 885                 mask = (uint64_t)temps[args[1]].mask >> tmp;
 886             }
 887             break;
 888
 889         case INDEX_op_extrl_i64_i32:
 890             mask = (uint32_t)temps[args[1]].mask;
 891             break;
 892         case INDEX_op_extrh_i64_i32:
 893             mask = (uint64_t)temps[args[1]].mask >> 32;
 894             break;
 895
 896         CASE_OP_32_64(shl):
 897             if (temp_is_const(args[2])) {
 898                 tmp = temps[args[2]].val & (TCG_TARGET_REG_BITS - 1);
 899                 mask = temps[args[1]].mask << tmp;
 900             }
 901             break;
 902
 903         CASE_OP_32_64(neg):
 904             /* Set to 1 all bits to the left of the rightmost.  */
 905             mask = -(temps[args[1]].mask & -temps[args[1]].mask);
 906             break;
 907
 908         CASE_OP_32_64(deposit):
 909             mask = deposit64(temps[args[1]].mask, args[3], args[4],
 910                              temps[args[2]].mask);
 911             break;
 912
 913         CASE_OP_32_64(or):
 914         CASE_OP_32_64(xor):
 915             mask = temps[args[1]].mask | temps[args[2]].mask;
 916             break;
 917
 918         CASE_OP_32_64(setcond):
 919         case INDEX_op_setcond2_i32:
 920             mask = 1;
 921             break;
 922
 923         CASE_OP_32_64(movcond):
 924             mask = temps[args[3]].mask | temps[args[4]].mask;
 925             break;
 926
 927         CASE_OP_32_64(ld8u):
 928             mask = 0xff;
 929             break;
 930         CASE_OP_32_64(ld16u):
 931             mask = 0xffff;
 932             break;
 933         case INDEX_op_ld32u_i64:
 934             mask = 0xffffffffu;
 935             break;
 936
 937         CASE_OP_32_64(qemu_ld):
 938             {
 939                 TCGMemOpIdx oi = args[nb_oargs + nb_iargs];
 940                 TCGMemOp mop = get_memop(oi);
 941                 if (!(mop & MO_SIGN)) {
 942                     mask = (2ULL << ((8 << (mop & MO_SIZE)) - 1)) - 1;
 943                 }
 944             }
 945             break;
 946
 947         default:
 948             break;
 949         }
 950
 951         /* 32-bit ops generate 32-bit results.  For the result is zero test
 952            below, we can ignore high bits, but for further optimizations we
 953            need to record that the high bits contain garbage.  */
 954         partmask = mask;
 955         if (!(def->flags & TCG_OPF_64BIT)) {
 956             mask |= ~(tcg_target_ulong)0xffffffffu;
 957             partmask &= 0xffffffffu;
 958             affected &= 0xffffffffu;
 959         }
 960
 961         if (partmask == 0) {
 962             tcg_debug_assert(nb_oargs == 1);
 963             tcg_opt_gen_movi(s, op, args, args[0], 0);
 964             continue;
 965         }
 966         if (affected == 0) {
 967             tcg_debug_assert(nb_oargs == 1);
 968             tcg_opt_gen_mov(s, op, args, args[0], args[1]);
 969             continue;
 970         }
 971
 972         /* Simplify expression for "op r, a, 0 => movi r, 0" cases */
 973         switch (opc) {
 974         CASE_OP_32_64(and):
 975         CASE_OP_32_64(mul):
 976         CASE_OP_32_64(muluh):
 977         CASE_OP_32_64(mulsh):
 978             if ((temp_is_const(args[2]) && temps[args[2]].val == 0)) {
 979                 tcg_opt_gen_movi(s, op, args, args[0], 0);
 980                 continue;
 981             }
 982             break;
 983         default:
 984             break;
 985         }
 986
 987         /* Simplify expression for "op r, a, a => mov r, a" cases */
 988         switch (opc) {
 989         CASE_OP_32_64(or):
 990         CASE_OP_32_64(and):
 991             if (temps_are_copies(args[1], args[2])) {
 992                 tcg_opt_gen_mov(s, op, args, args[0], args[1]);
 993                 continue;
 994             }
 995             break;
 996         default:
 997             break;
 998         }
 999
1000         /* Simplify expression for "op r, a, a => movi r, 0" cases */
1001         switch (opc) {
1002         CASE_OP_32_64(andc):
1003         CASE_OP_32_64(sub):
1004         CASE_OP_32_64(xor):
1005             if (temps_are_copies(args[1], args[2])) {
1006                 tcg_opt_gen_movi(s, op, args, args[0], 0);
1007                 continue;
1008             }
1009             break;
1010         default:
1011             break;
1012         }
1013
1014         /* Propagate constants through copy operations and do constant
1015            folding.  Constants will be substituted to arguments by register
1016            allocator where needed and possible.  Also detect copies. */
1017         switch (opc) {
1018         CASE_OP_32_64(mov):
1019             tcg_opt_gen_mov(s, op, args, args[0], args[1]);
1020             break;
1021         CASE_OP_32_64(movi):
1022             tcg_opt_gen_movi(s, op, args, args[0], args[1]);
1023             break;
1024
1025         CASE_OP_32_64(not):
1026         CASE_OP_32_64(neg):
1027         CASE_OP_32_64(ext8s):
1028         CASE_OP_32_64(ext8u):
1029         CASE_OP_32_64(ext16s):
1030         CASE_OP_32_64(ext16u):
1031         case INDEX_op_ext32s_i64:
1032         case INDEX_op_ext32u_i64:
1033         case INDEX_op_ext_i32_i64:
1034         case INDEX_op_extu_i32_i64:
1035         case INDEX_op_extrl_i64_i32:
1036         case INDEX_op_extrh_i64_i32:
1037             if (temp_is_const(args[1])) {
1038                 tmp = do_constant_folding(opc, temps[args[1]].val, 0);
1039                 tcg_opt_gen_movi(s, op, args, args[0], tmp);
1040                 break;
1041             }
1042             goto do_default;
1043
1044         CASE_OP_32_64(add):
1045         CASE_OP_32_64(sub):
1046         CASE_OP_32_64(mul):
1047         CASE_OP_32_64(or):
1048         CASE_OP_32_64(and):
1049         CASE_OP_32_64(xor):
1050         CASE_OP_32_64(shl):
1051         CASE_OP_32_64(shr):
1052         CASE_OP_32_64(sar):
1053         CASE_OP_32_64(rotl):
1054         CASE_OP_32_64(rotr):
1055         CASE_OP_32_64(andc):
1056         CASE_OP_32_64(orc):
1057         CASE_OP_32_64(eqv):
1058         CASE_OP_32_64(nand):
1059         CASE_OP_32_64(nor):
1060         CASE_OP_32_64(muluh):
1061         CASE_OP_32_64(mulsh):
1062         CASE_OP_32_64(div):
1063         CASE_OP_32_64(divu):
1064         CASE_OP_32_64(rem):
1065         CASE_OP_32_64(remu):
1066             if (temp_is_const(args[1]) && temp_is_const(args[2])) {
1067                 tmp = do_constant_folding(opc, temps[args[1]].val,
1068                                           temps[args[2]].val);
1069                 tcg_opt_gen_movi(s, op, args, args[0], tmp);
1070                 break;
1071             }
1072             goto do_default;
1073
1074         CASE_OP_32_64(deposit):
1075             if (temp_is_const(args[1]) && temp_is_const(args[2])) {
1076                 tmp = deposit64(temps[args[1]].val, args[3], args[4],
1077                                 temps[args[2]].val);
1078                 tcg_opt_gen_movi(s, op, args, args[0], tmp);
1079                 break;
1080             }
1081             goto do_default;
1082
1083         CASE_OP_32_64(setcond):
1084             tmp = do_constant_folding_cond(opc, args[1], args[2], args[3]);
1085             if (tmp != 2) {
1086                 tcg_opt_gen_movi(s, op, args, args[0], tmp);
1087                 break;
1088             }
1089             goto do_default;
1090
1091         CASE_OP_32_64(brcond):
1092             tmp = do_constant_folding_cond(opc, args[0], args[1], args[2]);
1093             if (tmp != 2) {
1094                 if (tmp) {
1095                     reset_all_temps(nb_temps);
1096                     op->opc = INDEX_op_br;
1097                     args[0] = args[3];
1098                 } else {
1099                     tcg_op_remove(s, op);
1100                 }
1101                 break;
1102             }
1103             goto do_default;
1104
1105         CASE_OP_32_64(movcond):
1106             tmp = do_constant_folding_cond(opc, args[1], args[2], args[5]);
1107             if (tmp != 2) {
1108                 tcg_opt_gen_mov(s, op, args, args[0], args[4-tmp]);
1109                 break;
1110             }
1111             goto do_default;
1112
1113         case INDEX_op_add2_i32:
1114         case INDEX_op_sub2_i32:
1115             if (temp_is_const(args[2]) && temp_is_const(args[3])
1116                 && temp_is_const(args[4]) && temp_is_const(args[5])) {
1117                 uint32_t al = temps[args[2]].val;
1118                 uint32_t ah = temps[args[3]].val;
1119                 uint32_t bl = temps[args[4]].val;
1120                 uint32_t bh = temps[args[5]].val;
1121                 uint64_t a = ((uint64_t)ah << 32) | al;
1122                 uint64_t b = ((uint64_t)bh << 32) | bl;
1123                 TCGArg rl, rh;
1124                 TCGOp *op2 = insert_op_before(s, op, INDEX_op_movi_i32, 2);
1125                 TCGArg *args2 = &s->gen_opparam_buf[op2->args];
1126
1127                 if (opc == INDEX_op_add2_i32) {
1128                     a += b;
1129                 } else {
1130                     a -= b;
1131                 }
1132
1133                 rl = args[0];
1134                 rh = args[1];
1135                 tcg_opt_gen_movi(s, op, args, rl, (int32_t)a);
1136                 tcg_opt_gen_movi(s, op2, args2, rh, (int32_t)(a >> 32));
1137
1138                 /* We've done all we need to do with the movi.  Skip it.  */
1139                 oi_next = op2->next;
1140                 break;
1141             }
1142             goto do_default;
1143
1144         case INDEX_op_mulu2_i32:
1145             if (temp_is_const(args[2]) && temp_is_const(args[3])) {
1146                 uint32_t a = temps[args[2]].val;
1147                 uint32_t b = temps[args[3]].val;
1148                 uint64_t r = (uint64_t)a * b;
1149                 TCGArg rl, rh;
1150                 TCGOp *op2 = insert_op_before(s, op, INDEX_op_movi_i32, 2);
1151                 TCGArg *args2 = &s->gen_opparam_buf[op2->args];
1152
1153                 rl = args[0];
1154                 rh = args[1];
1155                 tcg_opt_gen_movi(s, op, args, rl, (int32_t)r);
1156                 tcg_opt_gen_movi(s, op2, args2, rh, (int32_t)(r >> 32));
1157
1158                 /* We've done all we need to do with the movi.  Skip it.  */
1159                 oi_next = op2->next;
1160                 break;
1161             }
1162             goto do_default;
1163
1164         case INDEX_op_brcond2_i32:
1165             tmp = do_constant_folding_cond2(&args[0], &args[2], args[4]);
1166             if (tmp != 2) {
1167                 if (tmp) {
1168             do_brcond_true:
1169                     reset_all_temps(nb_temps);
1170                     op->opc = INDEX_op_br;
1171                     args[0] = args[5];
1172                 } else {
1173             do_brcond_false:
1174                     tcg_op_remove(s, op);
1175                 }
1176             } else if ((args[4] == TCG_COND_LT || args[4] == TCG_COND_GE)
1177                        && temp_is_const(args[2]) && temps[args[2]].val == 0
1178                        && temp_is_const(args[3]) && temps[args[3]].val == 0) {
1179                 /* Simplify LT/GE comparisons vs zero to a single compare
1180                    vs the high word of the input.  */
1181             do_brcond_high:
1182                 reset_all_temps(nb_temps);
1183                 op->opc = INDEX_op_brcond_i32;
1184                 args[0] = args[1];
1185                 args[1] = args[3];
1186                 args[2] = args[4];
1187                 args[3] = args[5];
1188             } else if (args[4] == TCG_COND_EQ) {
1189                 /* Simplify EQ comparisons where one of the pairs
1190                    can be simplified.  */
1191                 tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
1192                                                args[0], args[2], TCG_COND_EQ);
1193                 if (tmp == 0) {
1194                     goto do_brcond_false;
1195                 } else if (tmp == 1) {
1196                     goto do_brcond_high;
1197                 }
1198                 tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
1199                                                args[1], args[3], TCG_COND_EQ);
1200                 if (tmp == 0) {
1201                     goto do_brcond_false;
1202                 } else if (tmp != 1) {
1203                     goto do_default;
1204                 }
1205             do_brcond_low:
1206                 reset_all_temps(nb_temps);
1207                 op->opc = INDEX_op_brcond_i32;
1208                 args[1] = args[2];
1209                 args[2] = args[4];
1210                 args[3] = args[5];
1211             } else if (args[4] == TCG_COND_NE) {
1212                 /* Simplify NE comparisons where one of the pairs
1213                    can be simplified.  */
1214                 tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
1215                                                args[0], args[2], TCG_COND_NE);
1216                 if (tmp == 0) {
1217                     goto do_brcond_high;
1218                 } else if (tmp == 1) {
1219                     goto do_brcond_true;
1220                 }
1221                 tmp = do_constant_folding_cond(INDEX_op_brcond_i32,
1222                                                args[1], args[3], TCG_COND_NE);
1223                 if (tmp == 0) {
1224                     goto do_brcond_low;
1225                 } else if (tmp == 1) {
1226                     goto do_brcond_true;
1227                 }
1228                 goto do_default;
1229             } else {
1230                 goto do_default;
1231             }
1232             break;
1233
1234         case INDEX_op_setcond2_i32:
1235             tmp = do_constant_folding_cond2(&args[1], &args[3], args[5]);
1236             if (tmp != 2) {
1237             do_setcond_const:
1238                 tcg_opt_gen_movi(s, op, args, args[0], tmp);
1239             } else if ((args[5] == TCG_COND_LT || args[5] == TCG_COND_GE)
1240                        && temp_is_const(args[3]) && temps[args[3]].val == 0
1241                        && temp_is_const(args[4]) && temps[args[4]].val == 0) {
1242                 /* Simplify LT/GE comparisons vs zero to a single compare
1243                    vs the high word of the input.  */
1244             do_setcond_high:
1245                 reset_temp(args[0]);
1246                 temps[args[0]].mask = 1;
1247                 op->opc = INDEX_op_setcond_i32;
1248                 args[1] = args[2];
1249                 args[2] = args[4];
1250                 args[3] = args[5];
1251             } else if (args[5] == TCG_COND_EQ) {
1252                 /* Simplify EQ comparisons where one of the pairs
1253                    can be simplified.  */
1254                 tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
1255                                                args[1], args[3], TCG_COND_EQ);
1256                 if (tmp == 0) {
1257                     goto do_setcond_const;
1258                 } else if (tmp == 1) {
1259                     goto do_setcond_high;
1260                 }
1261                 tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
1262                                                args[2], args[4], TCG_COND_EQ);
1263                 if (tmp == 0) {
1264                     goto do_setcond_high;
1265                 } else if (tmp != 1) {
1266                     goto do_default;
1267                 }
1268             do_setcond_low:
1269                 reset_temp(args[0]);
1270                 temps[args[0]].mask = 1;
1271                 op->opc = INDEX_op_setcond_i32;
1272                 args[2] = args[3];
1273                 args[3] = args[5];
1274             } else if (args[5] == TCG_COND_NE) {
1275                 /* Simplify NE comparisons where one of the pairs
1276                    can be simplified.  */
1277                 tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
1278                                                args[1], args[3], TCG_COND_NE);
1279                 if (tmp == 0) {
1280                     goto do_setcond_high;
1281                 } else if (tmp == 1) {
1282                     goto do_setcond_const;
1283                 }
1284                 tmp = do_constant_folding_cond(INDEX_op_setcond_i32,
1285                                                args[2], args[4], TCG_COND_NE);
1286                 if (tmp == 0) {
1287                     goto do_setcond_low;
1288                 } else if (tmp == 1) {
1289                     goto do_setcond_const;
1290                 }
1291                 goto do_default;
1292             } else {
1293                 goto do_default;
1294             }
1295             break;
1296
1297         case INDEX_op_call:
1298             if (!(args[nb_oargs + nb_iargs + 1]
1299                   & (TCG_CALL_NO_READ_GLOBALS | TCG_CALL_NO_WRITE_GLOBALS))) {
1300                 for (i = 0; i < nb_globals; i++) {
1301                     if (test_bit(i, temps_used.l)) {
1302                         reset_temp(i);
1303                     }
1304                 }
1305             }
1306             goto do_reset_output;
1307
1308         default:
1309         do_default:
1310             /* Default case: we know nothing about operation (or were unable
1311                to compute the operation result) so no propagation is done.
1312                We trash everything if the operation is the end of a basic
1313                block, otherwise we only trash the output args.  "mask" is
1314                the non-zero bits mask for the first output arg.  */
1315             if (def->flags & TCG_OPF_BB_END) {
1316                 reset_all_temps(nb_temps);
1317             } else {
1318         do_reset_output:
1319                 for (i = 0; i < nb_oargs; i++) {
1320                     reset_temp(args[i]);
1321                     /* Save the corresponding known-zero bits mask for the
1322                        first output argument (only one supported so far). */
1323                     if (i == 0) {
1324                         temps[args[i]].mask = mask;
1325                     }
1326                 }
1327             }
1328             break;
1329         }
1330     }
1331 }