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_EAX           0x00
  15 #define R_ECX           0x01
  16 #define R_EDX           0x02
  17 #define R_EBX           0x03
  18 #define R_ESP           0x04
  19 #define R_EBP           0x05
  20 #define R_ESI           0x06
  21 #define R_EDI           0x07
  22 #define NREGS           0x08
  23
  24 #define MOV_M2R         0x8b
  25 #define MOV_R2X         0x89
  26 #define MOV_I2X         0xc7
  27 #define MOV_I2R         0xb8
  28 #define ADD_R2X         0x03
  29 #define SUB_R2X         0x2b
  30 #define SHX_REG         0xd3
  31 #define CMP_R2X         0x3b
  32 #define LEA_M2R         0x8d
  33 #define NEG_REG         0xf7
  34 #define NOT_REG         0xf7
  35 #define CALL_REG        0xff
  36 #define MUL_A2X         0xf7
  37 #define XOR_R2X         0x33
  38 #define AND_R2X         0x23
  39 #define OR_R2X          0x0b
  40 #define TEST_R2R        0x85
  41 #define INC_X           0xff
  42
  43 #define MIN(a, b)               ((a) < (b) ? (a) : (b))
  44
  45 #define TMP_BT(t)               ((t)->flags & TMP_ADDR ? LONGSZ : (t)->bt)
  46 #define TMP_REG(t)              ((t)->flags & LOC_REG ? (t)->addr : reg_get(~0))
  47 #define TMP_REG2(t, r)          ((t)->flags & LOC_REG && (t)->addr != r ? \
  48                                         (t)->addr : reg_get(~(1 << r)))
  49 #define TMPBT(bt)               (BT_SZ(bt) >= 4 ? (bt) : (bt) & BT_SIGNED | 4)
  50
  51 #define R_BYTEREGS              (1 << R_EAX | 1 << R_EDX | 1 << R_ECX)
  52 #define TMP_BYTEREG(t)          ((t)->flags & LOC_REG && \
  53                                         (1 << (t)->addr) & R_BYTEREGS ? \
  54                                         (t)->addr : reg_get(R_BYTEREGS))
  55
  56 static char buf[SECSIZE];
  57 static char *cur;
  58 static int nogen;
  59 static long sp;
  60 static long spsub_addr;
  61 static long maxsp;
  62
  63 #define TMP(i)          (&tmps[ntmp - 1 - (i)])
  64
  65 static struct tmp {
  66         long addr;
  67         long off;       /* offset from a symbol or a local */
  68         unsigned flags;
  69         unsigned bt;
  70 } tmps[MAXTMP];
  71 static int ntmp;
  72
  73 static int tmpsp;
  74
  75 static struct tmp *regs[NREGS];
  76 static int tmpregs[] = {R_EAX, R_ESI, R_EDI, R_EBX, R_EDX, R_ECX};
  77
  78 #define MAXRET                  (1 << 8)
  79
  80 static long ret[MAXRET];
  81 static int nret;
  82
  83 static long cmp_last;
  84 static long cmp_setl;
  85
  86 static void putint(char *s, long n, int l)
  87 {
  88         while (l--) {
  89                 *s++ = n;
  90                 n >>= 8;
  91         }
  92 }
  93
  94 static void os(char *s, int n)
  95 {
  96         if (nogen)
  97                 return;
  98         while (n--)
  99                 *cur++ = *s++;
 100 }
 101
 102 static void oi(long n, int l)
 103 {
 104         if (nogen)
 105                 return;
 106         while (l--) {
 107                 *cur++ = n;
 108                 n >>= 8;
 109         }
 110 }
 111
 112 static long codeaddr(void)
 113 {
 114         return cur - buf;
 115 }
 116
 117 #define OP2(o2, o1)             (0x010000 | ((o2) << 8) | (o1))
 118 #define O2(op)                  (((op) >> 8) & 0xff)
 119 #define O1(op)                  ((op) & 0xff)
 120 #define MODRM(m, r1, r2)        ((m) << 6 | (r1) << 3 | (r2))
 121
 122 static void op_x(int op, int r1, int r2, int bt)
 123 {
 124         int sz = BT_SZ(bt);
 125         if (sz == 2)
 126                 oi(0x66, 1);
 127         if (op & 0x10000)
 128                 oi(O2(op), 1);
 129         oi(sz == 1 ? O1(op) & ~0x1 : O1(op), 1);
 130 }
 131
 132 #define op_mr           op_rm
 133
 134 /* op_*(): r=reg, m=mem, i=imm, s=sym */
 135 static void op_rm(int op, int src, int base, int off, int bt)
 136 {
 137         int dis = off == (char) off ? 1 : 4;
 138         int mod = dis == 4 ? 2 : 1;
 139         if (!off && base != R_EBP)
 140                 mod = 0;
 141         op_x(op, src, base, bt);
 142         oi(MODRM(mod, src & 0x07, base & 0x07), 1);
 143         if (base == R_ESP)
 144                 oi(0x24, 1);
 145         if (mod)
 146                 oi(off, dis);
 147 }
 148
 149 static void op_rr(int op, int src, int dst, int bt)
 150 {
 151         op_x(op, src, dst, bt);
 152         oi(MODRM(3, src & 0x07, dst & 0x07), 1);
 153 }
 154
 155 static void op_rs(int op, int src, long addr, int off, int bt)
 156 {
 157         op_x(op, src, 0, bt);
 158         oi(MODRM(0, src & 0x07, 5), 1);
 159         if (!nogen)
 160                 out_rela(addr, codeaddr(), 1);
 161         oi(off - 4, 4);
 162 }
 163
 164 static void op_ri(int op, int o3, int src, long num, int bt)
 165 {
 166         op_x(op, src, 0, bt);
 167         oi(MODRM(3, o3, src & 0x07), 1);
 168         oi(num, MIN(4, BT_SZ(bt)));
 169 }
 170
 171 static void op_sr(int op, int src, long addr, int off, int bt)
 172 {
 173         op_x(op, src, 0, bt);
 174         oi(MODRM(0, src & 0x07, 5), 1);
 175         if (!nogen)
 176                 out_rela(addr, codeaddr(), 1);
 177         oi(off - 4, 4);
 178 }
 179
 180 static void op_si(int op, int o3, long addr, int off, long num, int bt)
 181 {
 182         int sz = MIN(4, BT_SZ(bt));
 183         op_x(op, 0, 0, bt);
 184         oi(MODRM(0, o3, 5), 1);
 185         if (!nogen)
 186                 out_rela(addr, codeaddr(), 1);
 187         oi(off - 4 - sz, 4);
 188         oi(num, sz);
 189 }
 190
 191 static void op_mi(int op, int o3, int base, int off, long num, int bt)
 192 {
 193         int dis = off == (char) off ? 1 : 4;
 194         int mod = dis == 4 ? 2 : 1;
 195         if (!off && base != R_EBP)
 196                 mod = 0;
 197         op_x(op, 0, base, bt);
 198         oi(MODRM(mod, 0, base), 1);
 199         if (mod)
 200                 oi(off, dis);
 201         oi(num, MIN(4, BT_SZ(bt)));
 202 }
 203
 204 static long sp_push(int size)
 205 {
 206         sp += size;
 207         if (sp > maxsp)
 208                 maxsp = sp;
 209         return sp;
 210 }
 211
 212 #define LOC_NEW(f, l)           (((f) & ~LOC_MASK) | (l))
 213
 214 static void tmp_mem(struct tmp *tmp)
 215 {
 216         int src = tmp->addr;
 217         if (!(tmp->flags & LOC_REG))
 218                 return;
 219         if (tmpsp == -1)
 220                 tmpsp = sp;
 221         tmp->addr = -sp_push(LONGSZ);
 222         op_rm(MOV_R2X, src, R_EBP, tmp->addr, TMPBT(TMP_BT(tmp)));
 223         regs[src] = NULL;
 224         tmp->flags = LOC_NEW(tmp->flags, LOC_MEM);
 225 }
 226
 227 static int movxx_x2r(int bt)
 228 {
 229         int o2;
 230         if (BT_SZ(bt) == 1)
 231                 o2 = bt & BT_SIGNED ? 0xbe : 0xb6;
 232         else
 233                 o2 = bt & BT_SIGNED ? 0xbf : 0xb7;
 234         return OP2(0x0f, o2);
 235 }
 236
 237 #define MOVSXD          0x63
 238
 239 static void mov_r2r(int r1, int r2, unsigned bt1, unsigned bt2)
 240 {
 241         int s1 = bt1 & BT_SIGNED;
 242         int s2 = bt2 & BT_SIGNED;
 243         int sz1 = BT_SZ(bt1);
 244         int sz2 = BT_SZ(bt2);
 245         if (sz2 < 4 && (sz1 > sz2 || s1 != s2)) {
 246                 op_rr(movxx_x2r(bt2), r1, r2, 4);
 247                 return;
 248         }
 249         if (sz1 == 4 && sz2 == 8 && s1) {
 250                 op_rr(MOVSXD, r2, r1, sz2);
 251                 return;
 252         }
 253         if (r1 != r2 || sz1 > sz2)
 254                 op_rr(MOV_R2X, r1, r2, TMPBT(bt2));
 255 }
 256
 257 static void mov_m2r(int dst, int base, int off, int bt1, int bt2)
 258 {
 259         if (BT_SZ(bt1) < 4) {
 260                 op_rm(movxx_x2r(bt1), dst, base, off,
 261                         bt1 & BT_SIGNED && BT_SZ(bt2) == 8 ? 8 : 4);
 262                 mov_r2r(dst, dst, bt1, bt2);
 263         } else {
 264                 op_rm(MOV_M2R, dst, base, off, bt1);
 265                 mov_r2r(dst, dst, bt1, bt2);
 266         }
 267 }
 268
 269 static void num_cast(struct tmp *t, unsigned bt)
 270 {
 271         if (!(bt & BT_SIGNED) && BT_SZ(bt) != LONGSZ)
 272                 t->addr &= ((1l << (long) (BT_SZ(bt) * 8)) - 1);
 273         if (bt & BT_SIGNED && BT_SZ(bt) != LONGSZ &&
 274                                 t->addr > (1l << (BT_SZ(bt) * 8 - 1)))
 275                 t->addr = -((1l << (BT_SZ(bt) * 8)) - t->addr);
 276         t->bt = bt;
 277 }
 278
 279 static void num_reg(int reg, unsigned bt, long num)
 280 {
 281         int op = MOV_I2R + (reg & 7);
 282         op_x(op, 0, reg, bt);
 283         oi(num, BT_SZ(bt));
 284 }
 285
 286 static void tmp_reg(struct tmp *tmp, int dst, unsigned bt, int deref)
 287 {
 288         if (deref && tmp->flags & TMP_ADDR)
 289                 tmp->flags &= ~TMP_ADDR;
 290         else
 291                 deref = 0;
 292         if (tmp->flags & LOC_NUM) {
 293                 num_cast(tmp, bt);
 294                 tmp->bt = TMPBT(bt);
 295                 num_reg(dst, tmp->bt, tmp->addr);
 296                 tmp->addr = dst;
 297                 regs[dst] = tmp;
 298                 tmp->flags = LOC_NEW(tmp->flags, LOC_REG);
 299         }
 300         if (tmp->flags & LOC_SYM) {
 301                 op_rr(MOV_I2X, 0, dst, 4);
 302                 if (!nogen)
 303                         out_rela(tmp->addr, codeaddr(), 0);
 304                 oi(tmp->off, 4);
 305                 tmp->addr = dst;
 306                 regs[dst] = tmp;
 307                 tmp->flags = LOC_NEW(tmp->flags, LOC_REG);
 308         }
 309         if (tmp->flags & LOC_REG) {
 310                 if (deref)
 311                         mov_m2r(dst, tmp->addr, 0, tmp->bt, bt);
 312                 else
 313                         mov_r2r(tmp->addr, dst, TMP_BT(tmp),
 314                                 tmp->flags & TMP_ADDR ? LONGSZ : bt);
 315                 regs[tmp->addr] = NULL;
 316         }
 317         if (tmp->flags & LOC_LOCAL) {
 318                 if (deref)
 319                         mov_m2r(dst, R_EBP, tmp->addr + tmp->off, tmp->bt, bt);
 320                 else
 321                         op_rm(LEA_M2R, dst, R_EBP, tmp->addr + tmp->off, LONGSZ);
 322         }
 323         if (tmp->flags & LOC_MEM) {
 324                 int nbt = deref ? LONGSZ : TMP_BT(tmp);
 325                 mov_m2r(dst, R_EBP, tmp->addr, nbt, nbt);
 326                 if (deref)
 327                         mov_m2r(dst, dst, 0, tmp->bt, bt);
 328         }
 329         tmp->addr = dst;
 330         tmp->bt = tmp->flags & TMP_ADDR ? bt : TMPBT(bt);
 331         regs[dst] = tmp;
 332         tmp->flags = LOC_NEW(tmp->flags, LOC_REG);
 333 }
 334
 335 static void reg_free(int reg)
 336 {
 337         int i;
 338         if (!regs[reg])
 339                 return;
 340         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 341                 if (!regs[tmpregs[i]]) {
 342                         tmp_reg(regs[reg], tmpregs[i], regs[reg]->bt, 0);
 343                         return;
 344                 }
 345         tmp_mem(regs[reg]);
 346 }
 347
 348 static void reg_for(int reg, struct tmp *t)
 349 {
 350         if (regs[reg] && regs[reg] != t)
 351                 reg_free(reg);
 352 }
 353
 354 static void tmp_mv(struct tmp *t, int reg)
 355 {
 356         reg_for(reg, t);
 357         tmp_reg(t, reg, t->bt, 0);
 358 }
 359
 360 static void tmp_to(struct tmp *t, int reg, int bt)
 361 {
 362         reg_for(reg, t);
 363         tmp_reg(t, reg, bt ? bt : t->bt, 1);
 364 }
 365
 366 static void tmp_drop(int n)
 367 {
 368         int i;
 369         for (i = ntmp - n; i < ntmp; i++)
 370                 if (tmps[i].flags & LOC_REG)
 371                         regs[tmps[i].addr] = NULL;
 372         cmp_last = -1;
 373         ntmp -= n;
 374 }
 375
 376 static int tmp_pop(int reg, int bt)
 377 {
 378         struct tmp *t = TMP(0);
 379         tmp_to(t, reg, bt);
 380         tmp_drop(1);
 381         return t->bt;
 382 }
 383
 384 static struct tmp *tmp_new(void)
 385 {
 386         cmp_last = -1;
 387         return &tmps[ntmp++];
 388 }
 389
 390 static void tmp_push(int reg, unsigned bt)
 391 {
 392         struct tmp *t = tmp_new();
 393         t->addr = reg;
 394         t->bt = bt;
 395         t->flags = LOC_REG;
 396         regs[reg] = t;
 397 }
 398
 399 void o_local(long addr, unsigned bt)
 400 {
 401         struct tmp *t = tmp_new();
 402         t->addr = -addr;
 403         t->bt = bt;
 404         t->flags = LOC_LOCAL | TMP_ADDR;
 405         t->off = 0;
 406 }
 407
 408 void o_num(long num, unsigned bt)
 409 {
 410         struct tmp *t = tmp_new();
 411         t->addr = num;
 412         t->bt = bt;
 413         t->flags = LOC_NUM;
 414 }
 415
 416 void o_symaddr(long addr, unsigned bt)
 417 {
 418         struct tmp *t = tmp_new();
 419         t->bt = bt;
 420         t->addr = addr;
 421         t->flags = LOC_SYM | TMP_ADDR;
 422         t->off = 0;
 423 }
 424
 425 void o_tmpdrop(int n)
 426 {
 427         if (n == -1 || n > ntmp)
 428                 n = ntmp;
 429         tmp_drop(n);
 430         if (!ntmp) {
 431                 if (tmpsp != -1)
 432                         sp = tmpsp;
 433                 tmpsp = -1;
 434         }
 435 }
 436
 437 #define FORK_REG                R_EAX
 438
 439 /* make sure tmps remain intact after a conditional expression */
 440 void o_fork(void)
 441 {
 442         int i;
 443         for (i = 0; i < ntmp - 1; i++)
 444                 tmp_mem(&tmps[i]);
 445 }
 446
 447 void o_forkpush(void)
 448 {
 449         tmp_pop(R_EAX, 0);
 450 }
 451
 452 void o_forkjoin(void)
 453 {
 454         tmp_push(FORK_REG, 0);
 455 }
 456
 457 void o_tmpswap(void)
 458 {
 459         struct tmp *t1 = TMP(0);
 460         struct tmp *t2 = TMP(1);
 461         struct tmp t;
 462         memcpy(&t, t1, sizeof(t));
 463         memcpy(t1, t2, sizeof(t));
 464         memcpy(t2, &t, sizeof(t));
 465         if (t1->flags & LOC_REG)
 466                 regs[t1->addr] = t1;
 467         if (t2->flags & LOC_REG)
 468                 regs[t2->addr] = t2;
 469 }
 470
 471 static int reg_get(int mask)
 472 {
 473         int i;
 474         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 475                 if ((1 << tmpregs[i]) & mask && !regs[tmpregs[i]])
 476                         return tmpregs[i];
 477         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 478                 if ((1 << tmpregs[i]) & mask) {
 479                         reg_free(tmpregs[i]);
 480                         return tmpregs[i];
 481                 }
 482         return 0;
 483 }
 484
 485 void tmp_copy(struct tmp *t1)
 486 {
 487         struct tmp *t2 = tmp_new();
 488         memcpy(t2, t1, sizeof(*t1));
 489         if (!(t1->flags & (LOC_REG | LOC_MEM)))
 490                 return;
 491         if (t1->flags & LOC_MEM) {
 492                 tmp_reg(t2, reg_get(~0), t2->bt, 0);
 493         } else if (t1->flags & LOC_REG) {
 494                 t2->addr = reg_get(~(1 << t1->addr));
 495                 op_rr(MOV_R2X, t1->addr, t2->addr, TMPBT(TMP_BT(t1)));
 496                 regs[t2->addr] = t2;
 497         }
 498 }
 499
 500 void o_tmpcopy(void)
 501 {
 502         tmp_copy(TMP(0));
 503 }
 504
 505 void o_cast(unsigned bt)
 506 {
 507         struct tmp *t = TMP(0);
 508         int reg;
 509         if (t->bt == bt)
 510                 return;
 511         if (t->flags & LOC_NUM) {
 512                 num_cast(t, bt);
 513                 return;
 514         }
 515         reg = BT_SZ(bt) > 1 ? TMP_REG(t) : TMP_BYTEREG(t);
 516         tmp_to(t, reg, bt);
 517 }
 518
 519 long o_func_beg(char *name, int global)
 520 {
 521         long addr = out_func_beg(name, global);
 522         cur = buf;
 523         os("\x55", 1);                  /* push %rbp */
 524         os("\x89\xe5", 2);              /* mov %rsp, %rbp */
 525         os("\x53\x56\x57", 3);          /* push ebx; push esi; push edi */
 526         sp = 3 * LONGSZ;
 527         maxsp = sp;
 528         ntmp = 0;
 529         tmpsp = -1;
 530         nret = 0;
 531         cmp_last = -1;
 532         memset(regs, 0, sizeof(regs));
 533         os("\x81\xec", 2);              /* sub $xxx, %rsp */
 534         spsub_addr = codeaddr();
 535         oi(0, 4);
 536         return addr;
 537 }
 538
 539 void o_deref(unsigned bt)
 540 {
 541         struct tmp *t = TMP(0);
 542         if (t->flags & TMP_ADDR)
 543                 tmp_to(t, TMP_REG(t), t->bt);
 544         t->bt = bt;
 545         t->flags |= TMP_ADDR;
 546 }
 547
 548 void o_load(void)
 549 {
 550         struct tmp *t = TMP(0);
 551         tmp_to(t, TMP_REG(t), t->bt);
 552 }
 553
 554 static unsigned bt_op(unsigned bt1, unsigned bt2)
 555 {
 556         unsigned s1 = BT_SZ(bt1);
 557         unsigned s2 = BT_SZ(bt2);
 558         unsigned bt = (bt1 | bt2) & BT_SIGNED | (s1 > s2 ? s1 : s2);
 559         return TMPBT(bt);
 560 }
 561
 562 #define TMP_NUM(t)      ((t)->flags & LOC_NUM && !((t)->flags & TMP_ADDR))
 563 #define LOCAL_PTR(t)    ((t)->flags & LOC_LOCAL && !((t)->flags & TMP_ADDR))
 564 #define SYM_PTR(t)      ((t)->flags & LOC_SYM && !((t)->flags & TMP_ADDR))
 565
 566 int o_popnum(long *c)
 567 {
 568         struct tmp *t = TMP(0);
 569         if (!TMP_NUM(t))
 570                 return 1;
 571         *c = t->addr;
 572         tmp_drop(1);
 573         return 0;
 574 }
 575
 576 static void shx(int uop, int sop)
 577 {
 578         struct tmp *t1 = TMP(0);
 579         struct tmp *t2 = TMP(1);
 580         int r2 = TMP_REG2(t2, R_ECX);
 581         int bt = t2->bt;
 582         tmp_to(t1, R_ECX, 0);
 583         tmp_to(t2, r2, 0);
 584         tmp_drop(1);
 585         op_rr(SHX_REG, bt & BT_SIGNED ? sop : uop, r2, TMPBT(bt));
 586 }
 587
 588 #define CQO_REG         0x99
 589
 590 static int mulop(int uop, int sop, int reg)
 591 {
 592         struct tmp *t1 = TMP(0);
 593         struct tmp *t2 = TMP(1);
 594         /* for div and mod, the sign of the second operand don't matter */
 595         int bt = uop == 4 ? bt_op(t1->bt, t2->bt) : TMPBT(t2->bt);
 596         if (t1->flags & LOC_REG && t1->addr != R_EAX && t1->addr != R_EDX)
 597                 reg = t1->addr;
 598         tmp_to(t1, reg, bt);
 599         tmp_to(t2, R_EAX, bt);
 600         if (reg != R_EDX) {
 601                 reg_free(R_EDX);
 602                 if (bt & BT_SIGNED)
 603                         op_x(CQO_REG, R_EAX, R_EDX, bt);
 604                 else
 605                         op_rr(XOR_R2X, R_EDX, R_EDX, bt);
 606         }
 607         tmp_drop(2);
 608         op_rr(MUL_A2X, bt & BT_SIGNED ? sop : uop, reg, TMPBT(t2->bt));
 609         return bt;
 610 }
 611
 612 void o_addr(void)
 613 {
 614         tmps[ntmp - 1].flags &= ~TMP_ADDR;
 615         tmps[ntmp - 1].bt = LONGSZ;
 616 }
 617
 618 void o_ret(unsigned bt)
 619 {
 620         if (bt)
 621                 tmp_pop(R_EAX, bt);
 622         else
 623                 os("\x31\xc0", 2);      /* xor %eax, %eax */
 624         ret[nret++] = o_jmp(0);
 625 }
 626
 627 static void inc(int op)
 628 {
 629         struct tmp *t = TMP(0);
 630         int reg;
 631         int off;
 632         if (t->flags & LOC_LOCAL) {
 633                 reg = R_EBP;
 634                 off = t->addr + t->off;
 635         } else {
 636                 reg = TMP_REG(t);
 637                 off = 0;
 638                 tmp_mv(t, reg);
 639         }
 640         op_rm(INC_X, op, reg, off, t->bt);
 641 }
 642
 643 void o_lnot(void)
 644 {
 645         if (cmp_last == codeaddr()) {
 646                 buf[cmp_setl + 1] ^= 0x01;
 647         } else {
 648                 o_num(0, 4 | BT_SIGNED);
 649                 o_bop(O_EQ);
 650         }
 651 }
 652
 653 void o_neg(int id)
 654 {
 655         struct tmp *t = TMP(0);
 656         int reg;
 657         unsigned bt = TMPBT(t->bt);
 658         reg = TMP_REG(t);
 659         tmp_to(t, reg, bt);
 660         op_rr(NOT_REG, id, reg, bt);
 661 }
 662
 663 #define ALIGN(x, a)             (((x) + (a) - 1) & ~((a) - 1))
 664
 665 void o_func_end(void)
 666 {
 667         int i;
 668         for (i = 0; i < nret; i++)
 669                 o_filljmp(ret[i]);
 670         os("\x5f\x5e\x5b", 3);          /* pop edi; pop esi; pop ebx */
 671         os("\xc9\xc3", 2);              /* leave; ret; */
 672         putint(buf + spsub_addr, ALIGN(maxsp - 3 * LONGSZ, LONGSZ), 4);
 673         out_func_end(buf, cur - buf);
 674 }
 675
 676 long o_mklocal(int size)
 677 {
 678         return sp_push(ALIGN(size, LONGSZ));
 679 }
 680
 681 void o_rmlocal(long addr, int sz)
 682 {
 683         sp = addr - sz;
 684 }
 685
 686 long o_arg(int i, unsigned bt)
 687 {
 688         return -LONGSZ * (i + 2);
 689 }
 690
 691 void o_assign(unsigned bt)
 692 {
 693         struct tmp *t1 = TMP(0);
 694         struct tmp *t2 = TMP(1);
 695         int r1 = BT_SZ(bt) > 1 ? TMP_REG(t1) : TMP_BYTEREG(t1);
 696         int reg;
 697         int off;
 698         tmp_to(t1, r1, TMPBT(bt));
 699         if (t2->flags & LOC_LOCAL) {
 700                 reg = R_EBP;
 701                 off = t2->addr + t2->off;
 702         } else {
 703                 reg = TMP_REG2(t2, r1);
 704                 off = 0;
 705                 tmp_mv(t2, reg);
 706         }
 707         tmp_drop(2);
 708         op_rm(MOV_R2X, r1, reg, off, bt);
 709         tmp_push(r1, bt);
 710 }
 711
 712 static long cu(int op, long i)
 713 {
 714         switch (op) {
 715         case O_NEG:
 716                 return -i;
 717         case O_NOT:
 718                 return ~i;
 719         case O_LNOT:
 720                 return !i;
 721         }
 722 }
 723
 724 static int c_uop(int op)
 725 {
 726         struct tmp *t1 = TMP(0);
 727         if (!TMP_NUM(t1))
 728                 return 1;
 729         tmp_drop(1);
 730         o_num(cu(op, t1->addr), t1->bt);
 731         return 0;
 732 }
 733
 734 static long cb(int op, long a, long b, int *bt, int bt1, int bt2)
 735 {
 736         *bt = bt_op(bt1, bt2);
 737         switch (op) {
 738         case O_ADD:
 739                 return a + b;
 740         case O_SUB:
 741                 return a - b;
 742         case O_AND:
 743                 return a & b;
 744         case O_OR:
 745                 return a | b;
 746         case O_XOR:
 747                 return a ^ b;
 748         case O_MUL:
 749                 return a * b;
 750         case O_DIV:
 751                 return a / b;
 752         case O_MOD:
 753                 return a % b;
 754         case O_SHL:
 755                 *bt = bt1;
 756                 return a << b;
 757         case O_SHR:
 758                 *bt = bt1;
 759                 if (bt1 & BT_SIGNED)
 760                         return a >> b;
 761                 else
 762                         return (unsigned long) a >> b;
 763         case O_LT:
 764                 *bt = 4;
 765                 return a < b;
 766         case O_GT:
 767                 *bt = 4;
 768                 return a > b;
 769         case O_LE:
 770                 *bt = 4;
 771                 return a <= b;
 772         case O_GE:
 773                 *bt = 4;
 774                 return a >= b;
 775         case O_EQ:
 776                 *bt = 4;
 777                 return a == b;
 778         case O_NEQ:
 779                 *bt = 4;
 780                 return a != b;
 781         }
 782 }
 783
 784 static int c_bop(int op)
 785 {
 786         struct tmp *t1 = TMP(0);
 787         struct tmp *t2 = TMP(1);
 788         int locals = LOCAL_PTR(t1) + LOCAL_PTR(t2);
 789         int syms = SYM_PTR(t1) + SYM_PTR(t2);
 790         int nums = TMP_NUM(t1) + TMP_NUM(t2);
 791         int bt;
 792         if (syms + locals == 2 || syms + nums + locals != 2)
 793                 return 1;
 794         if (nums == 1)
 795                 if (op != O_ADD && op != O_SUB || op == O_SUB && TMP_NUM(t2))
 796                         return 1;
 797         bt = BT_SIGNED | LONGSZ;
 798         if (nums == 2)
 799                 bt = bt_op(t1->bt, t2->bt);
 800         if (nums == 1) {
 801                 long o1 = TMP_NUM(t1) ? t1->addr : t1->off;
 802                 long o2 = TMP_NUM(t2) ? t2->addr : t2->off;
 803                 long ret = cb(op, o2, o1, &bt, t2->bt, t1->bt);
 804                 if (!TMP_NUM(t1))
 805                         o_tmpswap();
 806                 t2->off = ret;
 807                 tmp_drop(1);
 808         } else {
 809                 long ret = cb(op, t2->addr, t1->addr, &bt, t2->bt, t1->bt);
 810                 tmp_drop(2);
 811                 o_num(ret, bt);
 812         }
 813         return 0;
 814 }
 815
 816 void o_uop(int op)
 817 {
 818         if (!c_uop(op))
 819                 return;
 820         switch (op) {
 821         case O_NEG:
 822         case O_NOT:
 823                 o_neg(op == O_NEG ? 3 : 2);
 824                 break;
 825         case O_LNOT:
 826                 o_lnot();
 827                 break;
 828         case O_INC:
 829         case O_DEC:
 830                 inc(op == O_DEC);
 831                 break;
 832         }
 833 }
 834
 835 static int binop(int op, int *reg)
 836 {
 837         struct tmp *t1 = TMP(0);
 838         struct tmp *t2 = TMP(1);
 839         int r1, r2;
 840         unsigned bt = bt_op(t1->bt, t2->bt);
 841         r1 = TMP_REG(t1);
 842         r2 = TMP_REG2(t2, r1);
 843         tmp_pop(r1, bt);
 844         tmp_pop(r2, bt);
 845         op_rr(op, r2, r1, bt);
 846         *reg = r2;
 847         return bt;
 848 }
 849
 850 static void bin_add(int op)
 851 {
 852         /* opcode for O_ADD, O_SUB, O_AND, O_OR, O_XOR */
 853         static int rx[] = {0x03, 0x2b, 0x23, 0x0b, 0x33};
 854         int reg;
 855         int bt = binop(rx[op & 0x0f], &reg);
 856         tmp_push(reg, bt);
 857 }
 858
 859 static void bin_shx(int op)
 860 {
 861         if ((op & 0xff) == O_SHL)
 862                 shx(4, 4);
 863         else
 864                 shx(5, 7);
 865 }
 866
 867 static void bin_mul(int op)
 868 {
 869         if ((op & 0xff) == O_MUL)
 870                 tmp_push(R_EAX, mulop(4, 5, R_EDX));
 871         if ((op & 0xff) == O_DIV)
 872                 tmp_push(R_EAX, mulop(6, 7, R_ECX));
 873         if ((op & 0xff) == O_MOD)
 874                 tmp_push(R_EDX, mulop(6, 7, R_ECX));
 875 }
 876
 877 static void o_cmp(int uop, int sop)
 878 {
 879         struct tmp *t1 = TMP(0);
 880         struct tmp *t2 = TMP(1);
 881         char set[] = "\x0f\x00\xc0";
 882         int reg;
 883         int bt;
 884         if (regs[R_EAX] && regs[R_EAX] != t1 && regs[R_EAX] != t2)
 885                 reg_free(R_EAX);
 886         bt = binop(CMP_R2X, &reg);
 887         set[1] = bt & BT_SIGNED ? sop : uop;
 888         cmp_setl = codeaddr();
 889         os(set, 3);                     /* setl %al */
 890         os("\x0f\xb6\xc0", 3);          /* movzbl %al, %eax */
 891         tmp_push(R_EAX, 4 | BT_SIGNED);
 892         cmp_last = codeaddr();
 893 }
 894
 895 static void bin_cmp(int op)
 896 {
 897         switch (op & 0xff) {
 898         case O_LT:
 899                 o_cmp(0x92, 0x9c);
 900                 break;
 901         case O_GT:
 902                 o_cmp(0x97, 0x9f);
 903                 break;
 904         case O_LE:
 905                 o_cmp(0x96, 0x9e);
 906                 break;
 907         case O_GE:
 908                 o_cmp(0x93, 0x9d);
 909                 break;
 910         case O_EQ:
 911                 o_cmp(0x94, 0x94);
 912                 break;
 913         case O_NEQ:
 914                 o_cmp(0x95, 0x95);
 915                 break;
 916         }
 917 }
 918
 919 static void o_bopset(int op)
 920 {
 921         tmp_copy(TMP(1));
 922         o_tmpswap();
 923         o_bop(op & ~O_SET);
 924         o_assign(TMP(1)->bt);
 925 }
 926
 927 void o_bop(int op)
 928 {
 929         if (!(op & O_SET) && !c_bop(op))
 930                 return;
 931         if (op & O_SET) {
 932                 o_bopset(op);
 933                 return;
 934         }
 935         if ((op & 0xf0) == 0x00)
 936                 bin_add(op);
 937         if ((op & 0xf0) == 0x10)
 938                 bin_shx(op);
 939         if ((op & 0xf0) == 0x20)
 940                 bin_mul(op);
 941         if ((op & 0xf0) == 0x30)
 942                 bin_cmp(op);
 943 }
 944
 945 void o_memcpy(int sz)
 946 {
 947         struct tmp *t0 = TMP(-1);
 948         struct tmp *t1 = TMP(0);
 949         struct tmp *t2 = TMP(1);
 950         o_num(sz, 4);
 951         tmp_to(t0, R_ECX, 0);
 952         tmp_mv(t1, R_ESI);
 953         tmp_mv(t2, R_EDI);
 954         os("\xf3\xa4", 2);              /* rep movs */
 955         tmp_drop(2);
 956 }
 957
 958 void o_memset(int x, int sz)
 959 {
 960         struct tmp *t0 = TMP(-2);
 961         struct tmp *t1 = TMP(-1);
 962         struct tmp *t2 = TMP(0);
 963         o_num(sz, 4);
 964         o_num(x, 4);
 965         tmp_to(t0, R_EAX, 0);
 966         tmp_to(t1, R_ECX, 0);
 967         tmp_mv(t2, R_EDI);
 968         os("\xf3\xaa", 2);              /* rep stosb */
 969         tmp_drop(2);
 970 }
 971
 972 long o_mklabel(void)
 973 {
 974         return codeaddr();
 975 }
 976
 977 static long jx(int x, long addr)
 978 {
 979         char op[2] = {0x0f};
 980         op[1] = x;
 981         os(op, 2);              /* jx $addr */
 982         oi(addr - codeaddr() - 4, 4);
 983         return codeaddr() - 4;
 984 }
 985
 986 static long jxtest(int x, long addr)
 987 {
 988         int bt = tmp_pop(R_EAX, 0);
 989         op_rr(TEST_R2R, R_EAX, R_EAX, bt);
 990         return jx(x, addr);
 991 }
 992
 993 static long jxcmp(long addr, int inv)
 994 {
 995         int x;
 996         if (codeaddr() != cmp_last)
 997                 return -1;
 998         tmp_drop(1);
 999         cur = buf + cmp_setl;
1000         x = (unsigned char) buf[cmp_setl + 1];
1001         return jx((inv ? x : x ^ 0x01) & ~0x10, addr);
1002 }
1003
1004 long o_jz(long addr)
1005 {
1006         long ret = jxcmp(addr, 0);
1007         return ret != -1 ? ret : jxtest(0x84, addr);
1008 }
1009
1010 long o_jnz(long addr)
1011 {
1012         long ret = jxcmp(addr, 1);
1013         return ret != -1 ? ret : jxtest(0x85, addr);
1014 }
1015
1016 long o_jmp(long addr)
1017 {
1018         os("\xe9", 1);                  /* jmp $addr */
1019         oi(addr - codeaddr() - 4, 4);
1020         return codeaddr() - 4;
1021 }
1022
1023 void o_filljmp2(long addr, long jmpdst)
1024 {
1025         putint(buf + addr, jmpdst - addr - 4, 4);
1026 }
1027
1028 void o_filljmp(long addr)
1029 {
1030         o_filljmp2(addr, codeaddr());
1031 }
1032
1033 void o_call(int argc, unsigned *bt, unsigned ret_bt)
1034 {
1035         struct tmp *t;
1036         int i;
1037         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
1038                 if (regs[tmpregs[i]] && regs[tmpregs[i]] - tmps < ntmp - argc)
1039                         tmp_mem(regs[tmpregs[i]]);
1040         sp_push(LONGSZ * argc);
1041         for (i = argc - 1; i >= 0; --i) {
1042                 int reg = TMP_REG(TMP(0));
1043                 tmp_pop(reg, TMPBT(bt[i]));
1044                 op_rm(MOV_R2X, reg, R_ESP, i * LONGSZ, TMPBT(bt[i]));
1045         }
1046         t = TMP(0);
1047         if (t->flags & LOC_SYM) {
1048                 os("\xe8", 1);          /* call $x */
1049                 if (!nogen)
1050                         out_rela(t->addr, codeaddr(), 1);
1051                 oi(-4 + t->off, 4);
1052                 tmp_drop(1);
1053         } else {
1054                 tmp_mv(TMP(0), R_EAX);
1055                 tmp_drop(1);
1056                 op_rr(CALL_REG, 2, R_EAX, 4);
1057         }
1058         if (ret_bt)
1059                 tmp_push(R_EAX, ret_bt);
1060 }
1061
1062 int o_nogen(void)
1063 {
1064         return nogen++;
1065 }
1066
1067 void o_dogen(void)
1068 {
1069         nogen = 0;
1070 }
1071
1072 void o_datset(long addr, int off, unsigned bt)
1073 {
1074         struct tmp *t = TMP(0);
1075         if (t->flags & LOC_NUM && !(t->flags & TMP_ADDR)) {
1076                 num_cast(t, bt);
1077                 out_datcpy(addr, off, (void *) &t->addr, BT_SZ(bt));
1078         }
1079         if (t->flags & LOC_SYM && !(t->flags & TMP_ADDR)) {
1080                 out_datrela(t->addr, addr, off);
1081                 out_datcpy(addr, off, (void *) &t->off, BT_SZ(bt));
1082         }
1083         tmp_drop(1);
1084 }