gen.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #include "gen.h"
   4 #include "tok.h"
   5
   6 #define TMP_ADDR        0x0001
   7 #define LOC_REG         0x0100
   8 #define LOC_MEM         0x0200
   9 #define LOC_NUM         0x0400
  10 #define LOC_SYM         0x0800
  11 #define LOC_LOCAL       0x1000
  12 #define LOC_MASK        0xff00
  13
  14 #define R_RAX           0x00
  15 #define R_RCX           0x01
  16 #define R_RDX           0x02
  17 #define R_RBX           0x03
  18 #define R_RSP           0x04
  19 #define R_RBP           0x05
  20 #define R_RSI           0x06
  21 #define R_RDI           0x07
  22 #define R_R8            0x08
  23 #define R_R9            0x09
  24 #define R_R10           0x0a
  25 #define R_R11           0x0b
  26 #define R_R12           0x0c
  27 #define R_R13           0x0d
  28 #define R_R14           0x0e
  29 #define R_R15           0x0f
  30 #define NREGS           0x10
  31
  32 #define MOV_M2R         0x8b
  33 #define MOV_R2X         0x89
  34 #define MOV_I2X         0xc7
  35 #define MOV_I2R         0xb8
  36 #define ADD_R2X         0x03
  37 #define SUB_R2X         0x2b
  38 #define SHX_REG         0xd3
  39 #define CMP_R2X         0x3b
  40 #define LEA_M2R         0x8d
  41 #define NEG_REG         0xf7
  42 #define NOT_REG         0xf7
  43 #define CALL_REG        0xff
  44 #define MUL_A2X         0xf7
  45 #define XOR_R2X         0x33
  46 #define AND_R2X         0x23
  47 #define OR_R2X          0x0b
  48 #define TEST_R2R        0x85
  49 #define INC_X           0xff
  50
  51 #define MIN(a, b)               ((a) < (b) ? (a) : (b))
  52
  53 #define TMP_BT(t)               ((t)->flags & TMP_ADDR ? 8 : (t)->bt)
  54 #define TMP_REG(t)              ((t)->flags & LOC_REG ? (t)->addr : reg_get(~0))
  55 #define TMP_REG2(t, r)          ((t)->flags & LOC_REG && (t)->addr != r ? \
  56                                         (t)->addr : reg_get(~(1 << r)))
  57 #define BT_TMPBT(bt)            (BT_SZ(bt) >= 4 ? (bt) : (bt) & BT_SIGNED | 4)
  58
  59 static char buf[SECSIZE];
  60 static char *cur;
  61 static int nogen;
  62 static long sp;
  63 static long spsub_addr;
  64 static long maxsp;
  65
  66 #define TMP(i)          (&tmps[ntmp - 1 - (i)])
  67
  68 static struct tmp {
  69         long addr;
  70         long off;       /* used for LOC_SYM; offset from a symbol address */
  71         unsigned flags;
  72         unsigned bt;
  73 } tmps[MAXTMP];
  74 static int ntmp;
  75
  76 static int tmpsp;
  77
  78 static struct tmp *regs[NREGS];
  79 static int tmpregs[] = {R_RAX, R_RDI, R_RSI, R_RDX, R_RCX, R_R8, R_R9};
  80
  81 #define MAXRET                  (1 << 8)
  82
  83 static long ret[MAXRET];
  84 static int nret;
  85
  86 static long cmp_last;
  87 static long cmp_setl;
  88
  89 static void putint(char *s, long n, int l)
  90 {
  91         while (l--) {
  92                 *s++ = n;
  93                 n >>= 8;
  94         }
  95 }
  96
  97 static void os(char *s, int n)
  98 {
  99         if (nogen)
 100                 return;
 101         while (n--)
 102                 *cur++ = *s++;
 103 }
 104
 105 static void oi(long n, int l)
 106 {
 107         if (nogen)
 108                 return;
 109         while (l--) {
 110                 *cur++ = n;
 111                 n >>= 8;
 112         }
 113 }
 114
 115 static long codeaddr(void)
 116 {
 117         return cur - buf;
 118 }
 119
 120 #define OP2(o2, o1)             (0x0100 | ((o2) << 8) | (o1))
 121 #define O2(op)                  (((op) >> 8) & 0xff)
 122 #define O1(op)                  ((op) & 0xff)
 123
 124 static void o_op(int op, int r1, int r2, unsigned bt)
 125 {
 126         int rex = 0;
 127         int sz = BT_SZ(bt);
 128         if (r1 & 0x8)
 129                 rex |= 4;
 130         if (r2 & 0x8)
 131                 rex |= 1;
 132         if (sz == 8)
 133                 rex |= 8;
 134         if (sz == 1 && (r1 == R_RSI || r1 == R_RDI ||
 135                         r2 == R_RSI || r2 == R_RDI))
 136                 rex |= 0x40;
 137         /* hack: for movxx ops, bt does not represent the second arg */
 138         if (op & 0x100 && O2(op) == 0x0f && (O1(op) & 0xf7) == 0xb6 &&
 139                         (r2 == R_RSI || r2 == R_RDI))
 140                 rex |= 0x40;
 141         if (rex || sz == 8)
 142                 oi(0x40 | rex, 1);
 143         if (sz == 2)
 144                 oi(0x66, 1);
 145         if (op & 0x100)
 146                 oi(O2(op), 1);
 147         oi(sz == 1 ? O1(op) & ~0x1 : O1(op), 1);
 148 }
 149
 150 static void memop(int op, int src, int base, int off, unsigned bt)
 151 {
 152         int dis = off == (char) off ? 1 : 4;
 153         int mod = dis == 4 ? 2 : 1;
 154         o_op(op, src, base, bt);
 155         if (!off)
 156                 mod = 0;
 157         oi((mod << 6) | ((src & 0x07) << 3) | (base & 0x07), 1);
 158         if (off)
 159                 oi(off, dis);
 160 }
 161
 162 static void regop(int op, int src, int dst, unsigned bt)
 163 {
 164         o_op(op, src, dst, bt);
 165         oi((3 << 6) | (src << 3) | (dst & 0x07), 1);
 166 }
 167
 168 static long sp_push(int size)
 169 {
 170         sp += size;
 171         if (sp > maxsp)
 172                 maxsp = sp;
 173         return sp;
 174 }
 175
 176 #define LOC_NEW(f, l)           (((f) & ~LOC_MASK) | (l))
 177
 178 static void tmp_mem(struct tmp *tmp)
 179 {
 180         int src = tmp->addr;
 181         if (!(tmp->flags & LOC_REG))
 182                 return;
 183         if (tmpsp == -1)
 184                 tmpsp = sp;
 185         tmp->addr = -sp_push(8);
 186         memop(MOV_R2X, src, R_RBP, tmp->addr, BT_TMPBT(TMP_BT(tmp)));
 187         regs[src] = NULL;
 188         tmp->flags = LOC_NEW(tmp->flags, LOC_MEM);
 189 }
 190
 191 static int movxx_x2r(int bt)
 192 {
 193         int o2;
 194         if (BT_SZ(bt) == 1)
 195                 o2 = bt & BT_SIGNED ? 0xbe : 0xb6;
 196         else
 197                 o2 = bt & BT_SIGNED ? 0xbf : 0xb7;
 198         return OP2(0x0f, o2);
 199 }
 200
 201 #define MOVSXD          0x63
 202
 203 static void mov_r2r(int r1, int r2, unsigned bt1, unsigned bt2)
 204 {
 205         int s1 = bt1 & BT_SIGNED;
 206         int s2 = bt2 & BT_SIGNED;
 207         int sz1 = BT_SZ(bt1);
 208         int sz2 = BT_SZ(bt2);
 209         if (sz2 < 4 && (sz1 > sz2 || s1 != s2)) {
 210                 regop(movxx_x2r(bt2), r1, r2, 4);
 211                 return;
 212         }
 213         if (sz1 == 4 && sz2 == 8 && s1) {
 214                 regop(MOVSXD, r2, r1, sz2);
 215                 return;
 216         }
 217         if (r1 != r2 || sz1 > sz2)
 218                 regop(MOV_R2X, r1, r2, BT_TMPBT(bt2));
 219 }
 220
 221 static void mov_m2r(int dst, int base, int off, int bt1, int bt2)
 222 {
 223         if (BT_SZ(bt1) < 4) {
 224                 memop(movxx_x2r(bt1), dst, base, off,
 225                         bt1 & BT_SIGNED && BT_SZ(bt2) == 8 ? 8 : 4);
 226                 mov_r2r(dst, dst, bt1, bt2);
 227         } else {
 228                 memop(MOV_M2R, dst, base, off, bt1);
 229                 mov_r2r(dst, dst, bt1, bt2);
 230         }
 231 }
 232
 233 static void num_cast(struct tmp *t, unsigned bt)
 234 {
 235         if (!(bt & BT_SIGNED) && BT_SZ(bt) != 8)
 236                 t->addr &= ((1l << (long) (BT_SZ(bt) * 8)) - 1);
 237         if (bt & BT_SIGNED && BT_SZ(bt) != 8 &&
 238                                 t->addr > (1l << (BT_SZ(bt) * 8 - 1)))
 239                 t->addr = -((1l << (BT_SZ(bt) * 8)) - t->addr);
 240         t->bt = bt;
 241 }
 242
 243 static void num_reg(int reg, unsigned bt, long num)
 244 {
 245         int op = MOV_I2R + (reg & 7);
 246         if (BT_SZ(bt) == 8 && num >= 0 && num == (unsigned) num)
 247                 bt = 4;
 248         o_op(op, 0, reg, bt);
 249         oi(num, BT_SZ(bt));
 250 }
 251
 252 static void tmp_reg(struct tmp *tmp, int dst, unsigned bt, int deref)
 253 {
 254         if (deref && tmp->flags & TMP_ADDR)
 255                 tmp->flags &= ~TMP_ADDR;
 256         else
 257                 deref = 0;
 258         if (tmp->flags & LOC_NUM) {
 259                 num_cast(tmp, bt);
 260                 tmp->bt = BT_TMPBT(bt);
 261                 num_reg(dst, tmp->bt, tmp->addr);
 262                 tmp->addr = dst;
 263                 regs[dst] = tmp;
 264                 tmp->flags = LOC_NEW(tmp->flags, LOC_REG);
 265         }
 266         if (tmp->flags & LOC_SYM) {
 267                 regop(MOV_I2X, 0, dst, 4);
 268                 if (!nogen)
 269                         out_rela(tmp->addr, codeaddr(), 0);
 270                 oi(tmp->off, 4);
 271                 tmp->addr = dst;
 272                 regs[dst] = tmp;
 273                 tmp->flags = LOC_NEW(tmp->flags, LOC_REG);
 274         }
 275         if (tmp->flags & LOC_REG) {
 276                 if (deref)
 277                         mov_m2r(dst, tmp->addr, 0, tmp->bt, bt);
 278                 else
 279                         mov_r2r(tmp->addr, dst, TMP_BT(tmp),
 280                                 tmp->flags & TMP_ADDR ? 8 : bt);
 281                 regs[tmp->addr] = NULL;
 282         }
 283         if (tmp->flags & LOC_LOCAL) {
 284                 if (deref)
 285                         mov_m2r(dst, R_RBP, tmp->addr, tmp->bt, bt);
 286                 else
 287                         memop(LEA_M2R, dst, R_RBP, tmp->addr, 8);
 288         }
 289         if (tmp->flags & LOC_MEM) {
 290                 int nbt = deref ? 8 : TMP_BT(tmp);
 291                 mov_m2r(dst, R_RBP, tmp->addr, nbt, nbt);
 292                 if (deref)
 293                         mov_m2r(dst, dst, 0, tmp->bt, bt);
 294         }
 295         tmp->addr = dst;
 296         tmp->bt = tmp->flags & TMP_ADDR ? bt : BT_TMPBT(bt);
 297         regs[dst] = tmp;
 298         tmp->flags = LOC_NEW(tmp->flags, LOC_REG);
 299 }
 300
 301 static void reg_free(int reg)
 302 {
 303         int i;
 304         if (!regs[reg])
 305                 return;
 306         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 307                 if (!regs[tmpregs[i]]) {
 308                         tmp_reg(regs[reg], tmpregs[i], regs[reg]->bt, 0);
 309                         return;
 310                 }
 311         tmp_mem(regs[reg]);
 312 }
 313
 314 static void reg_for(int reg, struct tmp *t)
 315 {
 316         if (regs[reg] && regs[reg] != t)
 317                 reg_free(reg);
 318 }
 319
 320 static void tmp_mv(struct tmp *t, int reg)
 321 {
 322         reg_for(reg, t);
 323         tmp_reg(t, reg, t->bt, 0);
 324 }
 325
 326 static void tmp_to(struct tmp *t, int reg, int bt)
 327 {
 328         reg_for(reg, t);
 329         tmp_reg(t, reg, bt ? bt : t->bt, 1);
 330 }
 331
 332 static void tmp_drop(int n)
 333 {
 334         int i;
 335         for (i = ntmp - n; i < ntmp; i++)
 336                 if (tmps[i].flags & LOC_REG)
 337                         regs[tmps[i].addr] = NULL;
 338         cmp_last = -1;
 339         ntmp -= n;
 340 }
 341
 342 static int tmp_pop(int reg, int bt)
 343 {
 344         struct tmp *t = TMP(0);
 345         tmp_to(t, reg, bt);
 346         tmp_drop(1);
 347         return t->bt;
 348 }
 349
 350 static struct tmp *tmp_new(void)
 351 {
 352         cmp_last = -1;
 353         return &tmps[ntmp++];
 354 }
 355
 356 static void tmp_push(int reg, unsigned bt)
 357 {
 358         struct tmp *t = tmp_new();
 359         t->addr = reg;
 360         t->bt = bt;
 361         t->flags = LOC_REG;
 362         regs[reg] = t;
 363 }
 364
 365 void o_local(long addr, unsigned bt)
 366 {
 367         struct tmp *t = tmp_new();
 368         t->addr = -addr;
 369         t->bt = bt;
 370         t->flags = LOC_LOCAL | TMP_ADDR;
 371 }
 372
 373 void o_num(long num, unsigned bt)
 374 {
 375         struct tmp *t = tmp_new();
 376         t->addr = num;
 377         t->bt = bt;
 378         t->flags = LOC_NUM;
 379 }
 380
 381 void o_symaddr(long addr, unsigned bt)
 382 {
 383         struct tmp *t = tmp_new();
 384         t->bt = bt;
 385         t->addr = addr;
 386         t->flags = LOC_SYM | TMP_ADDR;
 387         t->off = 0;
 388 }
 389
 390 void o_tmpdrop(int n)
 391 {
 392         if (n == -1 || n > ntmp)
 393                 n = ntmp;
 394         tmp_drop(n);
 395         if (!ntmp) {
 396                 if (tmpsp != -1)
 397                         sp = tmpsp;
 398                 tmpsp = -1;
 399         }
 400 }
 401
 402 #define FORK_REG                R_RAX
 403
 404 /* make sure tmps remain intact after a conditional expression */
 405 void o_fork(void)
 406 {
 407         int i;
 408         for (i = 0; i < ntmp - 1; i++)
 409                 tmp_mem(&tmps[i]);
 410 }
 411
 412 void o_forkpush(void)
 413 {
 414         tmp_pop(R_RAX, 0);
 415 }
 416
 417 void o_forkjoin(void)
 418 {
 419         tmp_push(FORK_REG, 0);
 420 }
 421
 422 void o_tmpswap(void)
 423 {
 424         struct tmp *t1 = TMP(0);
 425         struct tmp *t2 = TMP(1);
 426         struct tmp t;
 427         memcpy(&t, t1, sizeof(t));
 428         memcpy(t1, t2, sizeof(t));
 429         memcpy(t2, &t, sizeof(t));
 430         if (t1->flags & LOC_REG)
 431                 regs[t1->addr] = t1;
 432         if (t2->flags & LOC_REG)
 433                 regs[t2->addr] = t2;
 434 }
 435
 436 static int reg_get(int mask)
 437 {
 438         int i;
 439         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 440                 if ((1 << tmpregs[i]) & mask && !regs[tmpregs[i]])
 441                         return tmpregs[i];
 442         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 443                 if ((1 << tmpregs[i]) & mask) {
 444                         reg_free(tmpregs[i]);
 445                         return tmpregs[i];
 446                 }
 447         return 0;
 448 }
 449
 450 void tmp_copy(struct tmp *t1)
 451 {
 452         struct tmp *t2 = tmp_new();
 453         memcpy(t2, t1, sizeof(*t1));
 454         if (!(t1->flags & (LOC_REG | LOC_MEM)))
 455                 return;
 456         if (t1->flags & LOC_MEM) {
 457                 tmp_reg(t2, reg_get(~0), t2->bt, 0);
 458         } else if (t1->flags & LOC_REG) {
 459                 t2->addr = reg_get(~(1 << t1->addr));
 460                 regop(MOV_R2X, t1->addr, t2->addr, BT_TMPBT(TMP_BT(t1)));
 461                 regs[t2->addr] = t2;
 462         }
 463 }
 464
 465 void o_tmpcopy(void)
 466 {
 467         tmp_copy(TMP(0));
 468 }
 469
 470 void o_cast(unsigned bt)
 471 {
 472         struct tmp *t = TMP(0);
 473         int reg;
 474         if (t->bt == bt)
 475                 return;
 476         if (t->flags & LOC_NUM) {
 477                 num_cast(t, bt);
 478                 return;
 479         }
 480         reg = TMP_REG(t);
 481         tmp_to(t, reg, bt);
 482 }
 483
 484 long o_func_beg(char *name, int global)
 485 {
 486         long addr = out_func_beg(name, global);
 487         cur = buf;
 488         os("\x55", 1);                  /* push %rbp */
 489         os("\x48\x89\xe5", 3);          /* mov %rsp, %rbp */
 490         sp = 0;
 491         maxsp = 0;
 492         ntmp = 0;
 493         tmpsp = -1;
 494         nret = 0;
 495         cmp_last = -1;
 496         memset(regs, 0, sizeof(regs));
 497         os("\x48\x81\xec", 3);          /* sub $xxx, %rsp */
 498         spsub_addr = codeaddr();
 499         oi(0, 4);
 500         return addr;
 501 }
 502
 503 void o_deref(unsigned bt)
 504 {
 505         struct tmp *t = TMP(0);
 506         if (t->flags & TMP_ADDR)
 507                 tmp_to(t, TMP_REG(t), t->bt);
 508         t->bt = bt;
 509         t->flags |= TMP_ADDR;
 510 }
 511
 512 void o_load(void)
 513 {
 514         struct tmp *t = TMP(0);
 515         tmp_to(t, TMP_REG(t), t->bt);
 516 }
 517
 518 static unsigned bt_op(unsigned bt1, unsigned bt2)
 519 {
 520         unsigned s1 = BT_SZ(bt1);
 521         unsigned s2 = BT_SZ(bt2);
 522         unsigned bt = (bt1 | bt2) & BT_SIGNED | (s1 > s2 ? s1 : s2);
 523         return BT_TMPBT(bt);
 524 }
 525
 526 #define TMP_CONST(t)    ((t)->flags & LOC_NUM && !((t)->flags & TMP_ADDR))
 527 #define LOCAL_PTR(t)    ((t)->flags & LOC_LOCAL && !((t)->flags & TMP_ADDR))
 528 #define SYM_PTR(t)      ((t)->flags & LOC_SYM && !((t)->flags & TMP_ADDR))
 529
 530 int o_popnum(long *c)
 531 {
 532         struct tmp *t = TMP(0);
 533         if (!TMP_CONST(t))
 534                 return 1;
 535         *c = t->addr;
 536         tmp_drop(1);
 537         return 0;
 538 }
 539
 540 static int c_op(long (*cop)(long a, unsigned bt), unsigned bt)
 541 {
 542         struct tmp *t1 = TMP(0);
 543         long ret;
 544         if (!TMP_CONST(t1))
 545                 return 1;
 546         if (!bt)
 547                 bt = t1->bt;
 548         ret = cop(t1->addr, bt);
 549         tmp_drop(1);
 550         o_num(ret, bt);
 551         return 0;
 552 }
 553
 554 static void shx(int uop, int sop)
 555 {
 556         struct tmp *t2 = TMP(1);
 557         int r2 = TMP_REG2(t2, R_RCX);
 558         int bt;
 559         tmp_pop(R_RCX, 0);
 560         bt = tmp_pop(r2, 0);
 561         regop(SHX_REG, bt & BT_SIGNED ? sop : uop, r2, BT_TMPBT(bt));
 562         tmp_push(r2, bt);
 563 }
 564
 565 static int mulop(int uop, int sop, int reg)
 566 {
 567         struct tmp *t1 = TMP(0);
 568         struct tmp *t2 = TMP(1);
 569         int bt = bt_op(t1->bt, t2->bt);
 570         if (t1->flags & LOC_REG && t1->addr != R_RAX && t1->addr != R_RDX)
 571                 reg = t1->addr;
 572         tmp_to(t1, reg, bt);
 573         tmp_to(t2, R_RAX, bt);
 574         if (reg != R_RDX) {
 575                 reg_free(R_RDX);
 576                 if (bt & BT_SIGNED)
 577                         o_op(0x99, R_RAX, R_RDX, bt);
 578                 else
 579                         regop(XOR_R2X, R_RDX, R_RDX, bt);
 580         }
 581         tmp_drop(2);
 582         regop(MUL_A2X, bt & BT_SIGNED ? sop : uop, reg, BT_TMPBT(t2->bt));
 583         return bt;
 584 }
 585
 586 void o_addr(void)
 587 {
 588         tmps[ntmp - 1].flags &= ~TMP_ADDR;
 589         tmps[ntmp - 1].bt = 8;
 590 }
 591
 592 void o_ret(unsigned bt)
 593 {
 594         if (bt)
 595                 tmp_pop(R_RAX, bt);
 596         else
 597                 os("\x31\xc0", 2);      /* xor %eax, %eax */
 598         ret[nret++] = o_jmp(0);
 599 }
 600
 601 static void inc(int op)
 602 {
 603         struct tmp *t = TMP(0);
 604         int reg;
 605         int off;
 606         if (t->flags & LOC_LOCAL) {
 607                 reg = R_RBP;
 608                 off = t->addr;
 609         } else {
 610                 reg = TMP_REG(t);
 611                 off = 0;
 612                 tmp_mv(t, reg);
 613         }
 614         memop(INC_X, op, reg, off, t->bt);
 615 }
 616
 617 void o_lnot(void)
 618 {
 619         if (cmp_last == codeaddr()) {
 620                 buf[cmp_setl + 1] ^= 0x01;
 621         } else {
 622                 o_num(0, 4 | BT_SIGNED);
 623                 o_bop(O_EQ);
 624         }
 625 }
 626
 627 void o_neg(int id)
 628 {
 629         struct tmp *t = TMP(0);
 630         int reg;
 631         unsigned bt = BT_TMPBT(t->bt);
 632         reg = TMP_REG(t);
 633         tmp_to(t, reg, bt);
 634         regop(NOT_REG, id, reg, bt);
 635 }
 636
 637 void o_func_end(void)
 638 {
 639         int i;
 640         for (i = 0; i < nret; i++)
 641                 o_filljmp(ret[i]);
 642         os("\xc9\xc3", 2);              /* leave; ret; */
 643         putint(buf + spsub_addr, (maxsp + 7) & ~0x07, 4);
 644         out_func_end(buf, cur - buf);
 645 }
 646
 647 long o_mklocal(int size)
 648 {
 649         return sp_push((size + 7) & ~0x07);
 650 }
 651
 652 void o_rmlocal(long addr, int sz)
 653 {
 654         sp = addr - sz;
 655 }
 656
 657 static int arg_regs[] = {R_RDI, R_RSI, R_RDX, R_RCX, R_R8, R_R9};
 658
 659 #define R_NARGS                 ARRAY_SIZE(arg_regs)
 660
 661 long o_arg(int i, unsigned bt)
 662 {
 663         long addr;
 664         if (i < R_NARGS) {
 665                 addr = o_mklocal(BT_SZ(bt));
 666                 memop(MOV_R2X, arg_regs[i], R_RBP, -addr, BT_TMPBT(bt));
 667         } else {
 668                 addr = -8 * (i - R_NARGS + 2);
 669         }
 670         return addr;
 671 }
 672
 673 void o_assign(unsigned bt)
 674 {
 675         struct tmp *t1 = TMP(0);
 676         struct tmp *t2 = TMP(1);
 677         int r1 = TMP_REG(t1);
 678         int reg;
 679         int off;
 680         tmp_to(t1, r1, BT_TMPBT(bt));
 681         if (t2->flags & LOC_LOCAL) {
 682                 reg = R_RBP;
 683                 off = t2->addr;
 684         } else {
 685                 reg = TMP_REG2(t2, r1);
 686                 off = 0;
 687                 tmp_mv(t2, reg);
 688         }
 689         tmp_drop(2);
 690         memop(MOV_R2X, r1, reg, off, bt);
 691         tmp_push(r1, bt);
 692 }
 693
 694 static long cu(int op, long i)
 695 {
 696         switch (op) {
 697         case O_NEG:
 698                 return -i;
 699         case O_NOT:
 700                 return ~i;
 701         case O_LNOT:
 702                 return !i;
 703         }
 704 }
 705
 706 static int c_uop(int op)
 707 {
 708         struct tmp *t1 = TMP(0);
 709         if (!TMP_CONST(t1))
 710                 return 1;
 711         tmp_drop(1);
 712         o_num(cu(op, t1->addr), t1->bt);
 713         return 0;
 714 }
 715
 716 static long cb(int op, long a, long b, int *bt)
 717 {
 718         switch (op) {
 719         case O_ADD:
 720                 return a + b;
 721         case O_SUB:
 722                 return a - b;
 723         case O_AND:
 724                 return a & b;
 725         case O_OR:
 726                 return a | b;
 727         case O_XOR:
 728                 return a ^ b;
 729         case O_MUL:
 730                 return a * b;
 731         case O_DIV:
 732                 return a / b;
 733         case O_MOD:
 734                 return a % b;
 735         case O_SHL:
 736                 return a << b;
 737         case O_SHR:
 738                 if (*bt & BT_SIGNED)
 739                         return a >> b;
 740                 else
 741                         return (unsigned long) a >> b;
 742         case O_LT:
 743                 *bt = 4;
 744                 return a < b;
 745         case O_GT:
 746                 *bt = 4;
 747                 return a > b;
 748         case O_LE:
 749                 *bt = 4;
 750                 return a <= b;
 751         case O_GE:
 752                 *bt = 4;
 753                 return a >= b;
 754         case O_EQ:
 755                 *bt = 4;
 756                 return a == b;
 757         case O_NEQ:
 758                 *bt = 4;
 759                 return a != b;
 760         }
 761 }
 762
 763 static int c_bop(int op)
 764 {
 765         struct tmp *t1 = TMP(0);
 766         struct tmp *t2 = TMP(1);
 767         int locals = LOCAL_PTR(t1) + LOCAL_PTR(t2);
 768         int syms = SYM_PTR(t1) + SYM_PTR(t2);
 769         int nums = TMP_CONST(t1) + TMP_CONST(t2);
 770         int bt;
 771         if (syms == 2 || syms && locals || syms + nums + locals != 2)
 772                 return 1;
 773         if (!locals)
 774                 bt = syms ? 8 : bt_op(t1->bt, t2->bt);
 775         if (locals == 1)
 776                 bt = 8;
 777         if (locals == 2)
 778                 bt = 4 | BT_SIGNED;
 779         if (syms) {
 780                 long o1 = SYM_PTR(t1) ? t1->off : t1->addr;
 781                 long o2 = SYM_PTR(t2) ? t2->off : t2->addr;
 782                 long ret = cb(op, o2, o1, &bt);
 783                 if (!SYM_PTR(t2))
 784                         o_tmpswap();
 785                 t2->off = ret;
 786                 tmp_drop(1);
 787         } else {
 788                 long ret = cb(op, t2->addr, t1->addr, &bt);
 789                 tmp_drop(2);
 790                 if (locals == 1) {
 791                         o_local(-ret, bt);
 792                         o_addr();
 793                 } else {
 794                         o_num(ret, bt);
 795                 }
 796         }
 797         return 0;
 798 }
 799
 800 void o_uop(int op)
 801 {
 802         if (!c_uop(op))
 803                 return;
 804         switch (op) {
 805         case O_NEG:
 806         case O_NOT:
 807                 o_neg(op == O_NEG ? 3 : 2);
 808                 break;
 809         case O_LNOT:
 810                 o_lnot();
 811                 break;
 812         case O_INC:
 813         case O_DEC:
 814                 inc(op == O_DEC);
 815                 break;
 816         }
 817 }
 818
 819 static int binop(int op, int *reg)
 820 {
 821         struct tmp *t1 = TMP(0);
 822         struct tmp *t2 = TMP(1);
 823         int r1, r2;
 824         unsigned bt = bt_op(t1->bt, t2->bt);
 825         r1 = TMP_REG(t1);
 826         r2 = TMP_REG2(t2, r1);
 827         tmp_pop(r1, bt);
 828         tmp_pop(r2, bt);
 829         regop(op, r2, r1, bt);
 830         *reg = r2;
 831         return bt;
 832 }
 833
 834 static void bin_add(int op)
 835 {
 836         /* opcode for O_ADD, O_SUB, O_AND, O_OR, O_XOR */
 837         static int rx[] = {0x03, 0x2b, 0x23, 0x0b, 0x33};
 838         int reg;
 839         int bt = binop(rx[op & 0x0f], &reg);
 840         tmp_push(reg, bt);
 841 }
 842
 843 static void bin_shx(int op)
 844 {
 845         if ((op & 0xff) == O_SHL)
 846                 shx(4, 4);
 847         else
 848                 shx(5, 7);
 849 }
 850
 851 static void bin_mul(int op)
 852 {
 853         if ((op & 0xff) == O_MUL)
 854                 tmp_push(R_RAX, mulop(4, 5, R_RDX));
 855         if ((op & 0xff) == O_DIV)
 856                 tmp_push(R_RAX, mulop(6, 7, R_RCX));
 857         if ((op & 0xff) == O_MOD)
 858                 tmp_push(R_RDX, mulop(6, 7, R_RCX));
 859 }
 860
 861 static void o_cmp(int uop, int sop)
 862 {
 863         struct tmp *t1 = TMP(0);
 864         struct tmp *t2 = TMP(1);
 865         char set[] = "\x0f\x00\xc0";
 866         int reg;
 867         int bt;
 868         if (regs[R_RAX] && regs[R_RAX] != t1 && regs[R_RAX] != t2)
 869                 reg_free(R_RAX);
 870         bt = binop(CMP_R2X, &reg);
 871         set[1] = bt & BT_SIGNED ? sop : uop;
 872         cmp_setl = codeaddr();
 873         os(set, 3);                     /* setl %al */
 874         os("\x0f\xb6\xc0", 3);          /* movzbl %al, %eax */
 875         tmp_push(R_RAX, 4 | BT_SIGNED);
 876         cmp_last = codeaddr();
 877 }
 878
 879 static void bin_cmp(int op)
 880 {
 881         switch (op & 0xff) {
 882         case O_LT:
 883                 o_cmp(0x92, 0x9c);
 884                 break;
 885         case O_GT:
 886                 o_cmp(0x97, 0x9f);
 887                 break;
 888         case O_LE:
 889                 o_cmp(0x96, 0x9e);
 890                 break;
 891         case O_GE:
 892                 o_cmp(0x93, 0x9d);
 893                 break;
 894         case O_EQ:
 895                 o_cmp(0x94, 0x94);
 896                 break;
 897         case O_NEQ:
 898                 o_cmp(0x95, 0x95);
 899                 break;
 900         }
 901 }
 902
 903 static void o_bopset(int op)
 904 {
 905         tmp_copy(TMP(1));
 906         o_tmpswap();
 907         o_bop(op & ~O_SET);
 908         o_assign(TMP(1)->bt);
 909 }
 910
 911 void o_bop(int op)
 912 {
 913         if (!(op & O_SET) && !c_bop(op))
 914                 return;
 915         if (op & O_SET) {
 916                 o_bopset(op);
 917                 return;
 918         }
 919         if ((op & 0xf0) == 0x00)
 920                 bin_add(op);
 921         if ((op & 0xf0) == 0x10)
 922                 bin_shx(op);
 923         if ((op & 0xf0) == 0x20)
 924                 bin_mul(op);
 925         if ((op & 0xf0) == 0x30)
 926                 bin_cmp(op);
 927 }
 928
 929 void o_memcpy(int sz)
 930 {
 931         struct tmp *t0 = TMP(-1);
 932         struct tmp *t1 = TMP(0);
 933         struct tmp *t2 = TMP(1);
 934         o_num(sz, 4);
 935         tmp_to(t0, R_RCX, 0);
 936         tmp_mv(t1, R_RSI);
 937         tmp_mv(t2, R_RDI);
 938         os("\xf3\xa4", 2);              /* rep movs */
 939         tmp_drop(2);
 940 }
 941
 942 void o_memset(int x, int sz)
 943 {
 944         struct tmp *t0 = TMP(-2);
 945         struct tmp *t1 = TMP(-1);
 946         struct tmp *t2 = TMP(0);
 947         o_num(sz, 4);
 948         o_num(x, 4);
 949         tmp_to(t0, R_RAX, 0);
 950         tmp_to(t1, R_RCX, 0);
 951         tmp_mv(t2, R_RDI);
 952         os("\xf3\xaa", 2);              /* rep stosb */
 953         tmp_drop(2);
 954 }
 955
 956 long o_mklabel(void)
 957 {
 958         return codeaddr();
 959 }
 960
 961 static long jx(int x, long addr)
 962 {
 963         char op[2] = {0x0f};
 964         op[1] = x;
 965         os(op, 2);              /* jx $addr */
 966         oi(addr - codeaddr() - 4, 4);
 967         return codeaddr() - 4;
 968 }
 969
 970 static long jxtest(int x, long addr)
 971 {
 972         int bt = tmp_pop(R_RAX, 0);
 973         regop(TEST_R2R, R_RAX, R_RAX, bt);
 974         return jx(x, addr);
 975 }
 976
 977 static long jxcmp(long addr, int inv)
 978 {
 979         int x;
 980         if (codeaddr() != cmp_last)
 981                 return -1;
 982         tmp_drop(1);
 983         cur = buf + cmp_setl;
 984         x = (unsigned char) buf[cmp_setl + 1];
 985         return jx((inv ? x : x ^ 0x01) & ~0x10, addr);
 986 }
 987
 988 long o_jz(long addr)
 989 {
 990         long ret = jxcmp(addr, 0);
 991         return ret != -1 ? ret : jxtest(0x84, addr);
 992 }
 993
 994 long o_jnz(long addr)
 995 {
 996         long ret = jxcmp(addr, 1);
 997         return ret != -1 ? ret : jxtest(0x85, addr);
 998 }
 999
1000 long o_jmp(long addr)
1001 {
1002         os("\xe9", 1);                  /* jmp $addr */
1003         oi(addr - codeaddr() - 4, 4);
1004         return codeaddr() - 4;
1005 }
1006
1007 void o_filljmp2(long addr, long jmpdst)
1008 {
1009         putint(buf + addr, jmpdst - addr - 4, 4);
1010 }
1011
1012 void o_filljmp(long addr)
1013 {
1014         o_filljmp2(addr, codeaddr());
1015 }
1016
1017 void o_call(int argc, unsigned *bt, unsigned ret_bt)
1018 {
1019         int i;
1020         struct tmp *t;
1021         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
1022                 if (regs[tmpregs[i]] && regs[tmpregs[i]] - tmps < ntmp - argc)
1023                         tmp_mem(regs[tmpregs[i]]);
1024         if (argc > R_NARGS) {
1025                 long addr = sp_push(8 * (argc - R_NARGS));
1026                 for (i = argc - 1; i >= R_NARGS; --i) {
1027                         int reg = TMP_REG(TMP(0));
1028                         tmp_pop(reg, bt[i]);
1029                         memop(MOV_R2X, reg, R_RBP,
1030                                 -(addr - (i - R_NARGS) * 8), BT_TMPBT(bt[i]));
1031                 }
1032         }
1033         for (i = MIN(argc, R_NARGS) - 1; i >= 0; i--)
1034                 tmp_pop(arg_regs[i], BT_TMPBT(bt[i]));
1035         t = TMP(0);
1036         if (t->flags & LOC_SYM) {
1037                 os("\x31\xc0", 2);      /* xor %eax, %eax */
1038                 os("\xe8", 1);          /* call $x */
1039                 if (!nogen)
1040                         out_rela(t->addr, codeaddr(), 1);
1041                 oi(-4 + t->off, 4);
1042                 tmp_drop(1);
1043         } else {
1044                 tmp_mv(TMP(0), R_RAX);
1045                 tmp_drop(1);
1046                 regop(CALL_REG, 2, R_RAX, 4);
1047         }
1048         if (ret_bt)
1049                 tmp_push(R_RAX, ret_bt);
1050 }
1051
1052 int o_nogen(void)
1053 {
1054         return nogen++;
1055 }
1056
1057 void o_dogen(void)
1058 {
1059         nogen = 0;
1060 }
1061
1062 void o_datset(long addr, int off, unsigned bt)
1063 {
1064         struct tmp *t = TMP(0);
1065         if (t->flags & LOC_NUM && !(t->flags & TMP_ADDR)) {
1066                 num_cast(t, bt);
1067                 out_datcpy(addr, off, (void *) &t->addr, BT_SZ(bt));
1068         }
1069         if (t->flags & LOC_SYM && !(t->flags & TMP_ADDR)) {
1070                 out_datrela(t->addr, addr, off);
1071                 out_datcpy(addr, off, (void *) &t->off, BT_SZ(bt));
1072         }
1073         tmp_drop(1);
1074 }