gen.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3 #include <string.h>
   4 #include "gen.h"
   5 #include "out.h"
   6 #include "tok.h"
   7
   8 #define LOC_REG         0x01
   9 #define LOC_MEM         0x02
  10 #define LOC_NUM         0x04
  11 #define LOC_SYM         0x08
  12 #define LOC_LOCAL       0x10
  13
  14 #define NREGS           16
  15
  16 #define REG_PC          15      /* program counter */
  17 #define REG_LR          14      /* link register */
  18 #define REG_SP          13      /* stack pointer */
  19 #define REG_TMP         12      /* temporary register */
  20 #define REG_FP          11      /* frame pointer register */
  21 #define REG_DP          10      /* data pointer register */
  22 #define REG_RET         0       /* returned value register */
  23
  24 #define MIN(a, b)               ((a) < (b) ? (a) : (b))
  25 #define ALIGN(x, a)             (((x) + (a) - 1) & ~((a) - 1))
  26
  27 static char cs[SECSIZE];        /* code segment */
  28 static int cslen;
  29 static char ds[SECSIZE];        /* data segment */
  30 static int dslen;
  31 static long bsslen;             /* bss segment size */
  32
  33 static int nogen;               /* don't generate code */
  34 static long sp;
  35 static long func_beg;
  36 static long maxsp;
  37
  38 #define TMP(i)          (((i) < ntmp) ? &tmps[ntmp - 1 - (i)] : NULL)
  39
  40 static struct tmp {
  41         long addr;
  42         char sym[NAMELEN];
  43         long off;       /* offset from a symbol or a local */
  44         unsigned loc;   /* variable location */
  45         unsigned bt;    /* type of address; zero when not a pointer */
  46 } tmps[MAXTMP];
  47 static int ntmp;
  48
  49 static int tmpsp;
  50
  51 static struct tmp *regs[NREGS];
  52 static int tmpregs[] = {4, 5, 6, 7, 8, 9, 0, 1, 2, 3};
  53 static int argregs[] = {0, 1, 2, 3};
  54
  55 #define I_AND           0x00
  56 #define I_EOR           0x01
  57 #define I_SUB           0x02
  58 #define I_RSB           0x03
  59 #define I_ADD           0x04
  60 #define I_TST           0x08
  61 #define I_CMP           0x0a
  62 #define I_ORR           0x0c
  63 #define I_MOV           0x0d
  64 #define I_MVN           0x0f
  65
  66 #define MAXRET                  (1 << 8)
  67
  68 static long ret[MAXRET];
  69 static int nret;
  70
  71 /* output div/mod functions */
  72 static int putdiv = 0;
  73
  74 /* for optimizing cmp + bcc */
  75 static long last_cmp = -1;
  76 static long last_set = -1;
  77 static long last_cond;
  78
  79 static void os(void *s, int n)
  80 {
  81         memcpy(cs + cslen, s, n);
  82         cslen += n;
  83 }
  84
  85 static void oi(long n)
  86 {
  87         if (nogen)
  88                 return;
  89         *(int *) (cs + cslen) = n;
  90         cslen += 4;
  91 }
  92
  93 #define MAXNUMS         1024
  94
  95 /* data pool */
  96 static long num_offs[MAXNUMS];                  /* data immediate value */
  97 static char num_names[MAXNUMS][NAMELEN];        /* relocation data symbol name */
  98 static int nums;
  99
 100 static int pool_find(char *name, int off)
 101 {
 102         int i;
 103         for (i = 0; i < nums; i++)
 104                 if (!strcmp(name, num_names[i]) && off == num_offs[i])
 105                         return i;
 106         return -1;
 107 }
 108
 109 static int pool_num(long num)
 110 {
 111         int idx = pool_find("", num);
 112         if (idx < 0) {
 113                 idx = nums++;
 114                 num_offs[idx] = num;
 115                 num_names[idx][0] = '\0';
 116         }
 117         return idx << 2;
 118 }
 119
 120 static int pool_reloc(char *name, long off)
 121 {
 122         int idx = pool_find(name, off);
 123         if (idx < 0) {
 124                 idx = nums++;
 125                 num_offs[idx] = off;
 126                 strcpy(num_names[idx], name);
 127         }
 128         return idx << 2;
 129 }
 130
 131 static void pool_write(void)
 132 {
 133         int i;
 134         for (i = 0; i < nums; i++) {
 135                 if (num_names[i])
 136                         out_rel(num_names[i], OUT_CS, cslen);
 137                 oi(num_offs[i]);
 138         }
 139 }
 140
 141 /*
 142  * data processing:
 143  * +---------------------------------------+
 144  * |COND|00|I| op |S| Rn | Rd |  operand2  |
 145  * +---------------------------------------+
 146  *
 147  * S: set condition code
 148  * Rn: first operand
 149  * Rd: destination operand
 150  *
 151  * I=0 operand2=| shift  | Rm |
 152  * I=1 operand2=|rota|  imm   |
 153  */
 154 #define ADD(op, rd, rn, s, i, cond)     \
 155         (((cond) << 28) | ((i) << 25) | ((s) << 20) | \
 156                 ((op) << 21) | ((rn) << 16) | ((rd) << 12))
 157
 158 static void i_add(int op, int rd, int rn, int rm)
 159 {
 160         oi(ADD(op, rd, rn, 0, 0, 14) | rm);
 161 }
 162
 163 static int add_encimm(unsigned n)
 164 {
 165         int i = 0;
 166         while (i < 12 && (n >> ((4 + i) << 1)))
 167                 i++;
 168         return (n >> (i << 1)) | (((16 - i) & 0x0f) << 8);
 169 }
 170
 171 static int add_decimm(unsigned n)
 172 {
 173         int rot = (16 - ((n >> 8) & 0x0f)) & 0x0f;
 174         return (n & 0xff) << (rot << 1);
 175 }
 176
 177 static int add_rndimm(unsigned n)
 178 {
 179         int rot = (n >> 8) & 0x0f;
 180         int num = n & 0xff;
 181         if (rot == 0)
 182                 return n;
 183         if (num == 0xff) {
 184                 num = 0;
 185                 rot = (rot + 12) & 0x0f;
 186         }
 187         return ((num + 1) & 0xff) | (rot << 8);
 188 }
 189
 190 static void i_ldr(int l, int rd, int rn, int off, int bt);
 191
 192 static void i_num(int rd, long n)
 193 {
 194         int neg = n < 0;
 195         int p = neg ? -n - 1 : n;
 196         int enc = add_encimm(p);
 197         if (p == add_decimm(enc)) {
 198                 oi(ADD(neg ? I_MVN : I_MOV, rd, 0, 0, 1, 14) | enc);
 199         } else {
 200                 if (!nogen) {
 201                         int off = pool_num(n);
 202                         i_ldr(1, rd, REG_DP, off, LONGSZ);
 203                 }
 204         }
 205 }
 206
 207 static void i_add_imm(int op, int rd, int rn, int n)
 208 {
 209         int neg = n < 0;
 210         int imm = add_encimm(neg ? -n : n);
 211         if (imm == add_decimm(neg ? -n : n)) {
 212                 oi(ADD(neg ? I_SUB : I_ADD, rd, rn, 0, 1, 14) | imm);
 213         } else {
 214                 i_num(rd, n);
 215                 i_add(I_ADD, rd, rd, rn);
 216         }
 217 }
 218
 219 /*
 220  * multiply
 221  * +----------------------------------------+
 222  * |COND|000000|A|S| Rd | Rn | Rs |1001| Rm |
 223  * +----------------------------------------+
 224  *
 225  * Rd: destination
 226  * A: accumulate
 227  * C: set condition codes
 228  *
 229  * I=0 operand2=| shift  | Rm |
 230  * I=1 operand2=|rota|  imm   |
 231  */
 232 #define MUL(rd, rn, rs)         \
 233         ((14 << 28) | ((rd) << 16) | ((0) << 12) | ((rn) << 8) | ((9) << 4) | (rm))
 234
 235 static void i_mul(int rd, int rn, int rm)
 236 {
 237         oi(MUL(rd, rn, rm));
 238 }
 239
 240 static void i_cmp(int op, int rn, int rm)
 241 {
 242         oi(ADD(op, 0, rn, 1, 0, 14) | rm);
 243         last_cmp = cslen;
 244 }
 245
 246 static void i_set(int cond, int rd)
 247 {
 248         last_set = cslen;
 249         last_cond = cond;
 250         oi(ADD(I_MOV, rd, 0, 0, 1, 14));
 251         oi(ADD(I_MOV, rd, 0, 0, 1, cond) | 1);
 252 }
 253
 254 #define SM_LSL          0
 255 #define SM_LSR          1
 256 #define SM_ASR          2
 257
 258 static void i_shl(int sm, int rd, int rm, int rs)
 259 {
 260         oi(ADD(I_MOV, rd, 0, 0, 0, 14) | (rs << 8) | (sm << 5) | (1 << 4) | rm);
 261 }
 262
 263 static void i_shl_imm(int sm, int rd, int n)
 264 {
 265         oi(ADD(I_MOV, rd, 0, 0, 0, 14) | (n << 7) | (sm << 5) | rd);
 266 }
 267
 268 static void i_mov(int op, int rd, int rn)
 269 {
 270         oi(ADD(op, rd, 0, 0, 0, 14) | rn);
 271 }
 272
 273 /*
 274  * single data transfer:
 275  * +------------------------------------------+
 276  * |COND|01|I|P|U|B|W|L| Rn | Rd |   offset   |
 277  * +------------------------------------------+
 278  *
 279  * I: immediate/offset
 280  * P: post/pre indexing
 281  * U: down/up
 282  * B: byte/word
 283  * W: writeback
 284  * L: store/load
 285  * Rn: base register
 286  * Rd: source/destination register
 287  *
 288  * I=0 offset=| immediate |
 289  * I=1 offset=| shift  | Rm |
 290  *
 291  * halfword and signed data transfer
 292  * +----------------------------------------------+
 293  * |COND|000|P|U|0|W|L| Rn | Rd |0000|1|S|H|1| Rm |
 294  * +----------------------------------------------+
 295  *
 296  * +----------------------------------------------+
 297  * |COND|000|P|U|1|W|L| Rn | Rd |off1|1|S|H|1|off2|
 298  * +----------------------------------------------+
 299  *
 300  * S: singed
 301  * H: halfword
 302  */
 303 #define LDR(l, rd, rn, b, u, p, w)              \
 304         ((14 << 28) | (1 << 26) | ((p) << 24) | ((b) << 22) | ((u) << 23) | \
 305         ((w) << 21) | ((l) << 20) | ((rn) << 16) | ((rd) << 12))
 306 #define LDRH(l, rd, rn, s, h, u, i)     \
 307         ((14 << 28) | (1 << 24) | ((u) << 23) | ((i) << 22) | ((l) << 20) | \
 308         ((rn) << 16) | ((rd) << 12) | ((s) << 6) | ((h) << 5) | (9 << 4))
 309
 310 static void i_ldr(int l, int rd, int rn, int off, int bt)
 311 {
 312         int b = BT_SZ(bt) == 1;
 313         int h = BT_SZ(bt) == 2;
 314         int s = l && (bt & BT_SIGNED);
 315         int half = h || (b && s);
 316         int maximm = half ? 0x100 : 0x1000;
 317         int neg = off < 0;
 318         if (neg)
 319                 off = -off;
 320         while (off >= maximm) {
 321                 int imm = add_encimm(off);
 322                 oi(ADD(neg ? I_SUB : I_ADD, REG_TMP, rn, 0, 1, 14) | imm);
 323                 rn = REG_TMP;
 324                 off -= add_decimm(imm);
 325         }
 326         if (!half)
 327                 oi(LDR(l, rd, rn, b, !neg, 1, 0) | off);
 328         else
 329                 oi(LDRH(l, rd, rn, s, h, !neg, 1) |
 330                         ((off & 0xf0) << 4) | (off & 0x0f));
 331 }
 332
 333 static void i_sym(int rd, char *sym, int off)
 334 {
 335         if (!nogen) {
 336                 int doff = pool_reloc(sym, off);
 337                 i_ldr(1, rd, REG_DP, doff, LONGSZ);
 338         }
 339 }
 340
 341 static void i_neg(int rd)
 342 {
 343         oi(ADD(I_RSB, rd, rd, 0, 1, 14));
 344 }
 345
 346 static void i_not(int rd)
 347 {
 348         oi(ADD(I_MVN, rd, 0, rd, 1, 14));
 349 }
 350
 351 static void i_lnot(int rd)
 352 {
 353         i_cmp(I_TST, rd, rd);
 354         oi(ADD(I_MOV, rd, 0, 0, 1, 14));
 355         oi(ADD(I_MOV, rd, 0, 0, 1, 0) | 1);
 356 }
 357
 358 /* rd = rd & ((1 << bits) - 1) */
 359 static void i_zx(int rd, int bits)
 360 {
 361         if (bits <= 8) {
 362                 oi(ADD(I_AND, rd, rd, 0, 1, 14) | add_encimm((1 << bits) - 1));
 363         } else {
 364                 i_shl_imm(SM_LSL, rd, 32 - bits);
 365                 i_shl_imm(SM_LSR, rd, 32 - bits);
 366         }
 367 }
 368
 369 static void i_sx(int rd, int bits)
 370 {
 371         i_shl_imm(SM_LSL, rd, 32 - bits);
 372         i_shl_imm(SM_ASR, rd, 32 - bits);
 373 }
 374
 375 /*
 376  * branch:
 377  * +-----------------------------------+
 378  * |COND|101|L|         offset         |
 379  * +-----------------------------------+
 380  *
 381  * L: link
 382  */
 383 #define BL(cond, l, o)  (((cond) << 28) | (5 << 25) | ((l) << 24) | \
 384                                 ((((o) - 8) >> 2) & 0x00ffffff))
 385
 386 static void i_b(long addr)
 387 {
 388         oi(BL(14, 0, addr - cslen));
 389 }
 390
 391 static void i_b_if(long addr, int rn, int z)
 392 {
 393         static int nots[] = {1, 0, 3, 2, -1, -1, -1, -1, 9, 8, 11, 10, 13, 12, -1};
 394         if (last_cmp + 8 != cslen || last_set != last_cmp) {
 395                 i_cmp(I_TST, rn, rn);
 396                 oi(BL(z ? 0 : 1, 0, addr - cslen));
 397                 return;
 398         }
 399         cslen = last_cmp;
 400         oi(BL(z ? nots[last_cond] : last_cond, 0, addr - cslen));
 401 }
 402
 403 static void i_b_fill(long *dst, int diff)
 404 {
 405         *dst = (*dst & 0xff000000) | (((diff - 8) >> 2) & 0x00ffffff);
 406 }
 407
 408 static void i_memcpy(int rd, int rs, int rn)
 409 {
 410         oi(ADD(I_SUB, rn, rn, 1, 1, 14) | 1);
 411         oi(BL(4, 0, 16));
 412         oi(LDR(1, REG_TMP, rs, 1, 1, 0, 0) | 1);
 413         oi(LDR(0, REG_TMP, rd, 1, 1, 0, 0) | 1);
 414         oi(BL(14, 0, -16));
 415 }
 416
 417 static void i_memset(int rd, int rs, int rn)
 418 {
 419         oi(ADD(I_SUB, rn, rn, 1, 1, 14) | 1);
 420         oi(BL(4, 0, 12));
 421         oi(LDR(0, rs, rd, 1, 1, 0, 0) | 1);
 422         oi(BL(14, 0, -12));
 423 }
 424
 425 static void i_call_reg(int rd)
 426 {
 427         i_mov(I_MOV, REG_LR, REG_PC);
 428         i_mov(I_MOV, REG_PC, rd);
 429 }
 430
 431 static void i_call(char *sym)
 432 {
 433         if (!nogen)
 434                 out_rel(sym, OUT_CS | OUT_REL24, cslen);
 435         oi(BL(14, 1, 0));
 436 }
 437
 438 static void i_prolog(void)
 439 {
 440         func_beg = cslen;
 441         nums = 0;
 442         oi(0xe1a0c00d);         /* mov   r12, sp */
 443         oi(0xe92d000f);         /* stmfd sp!, {r0-r3} */
 444         oi(0xe92d5ff0);         /* stmfd sp!, {r0-r11, r12, lr} */
 445         oi(0xe1a0b00d);         /* mov   fp, sp */
 446         oi(0xe24dd000);         /* sub   sp, sp, xx */
 447         oi(0xe28fa000);         /* add   dp, pc, xx */
 448 }
 449
 450 static void i_epilog(void)
 451 {
 452         int dpoff;
 453         oi(0xe89baff0);         /* ldmfd fp, {r4-r11, sp, pc} */
 454         dpoff = add_decimm(add_rndimm(add_encimm(cslen - func_beg - 28)));
 455         cslen = func_beg + dpoff + 28;
 456         maxsp = ALIGN(maxsp, 8);
 457         maxsp = add_decimm(add_rndimm(add_encimm(maxsp)));
 458         /* fill stack sub: sp = sp - xx */
 459         *(long *) (cs + func_beg + 16) |= add_encimm(maxsp);
 460         /* fill data ptr addition: dp = pc + xx */
 461         *(long *) (cs + func_beg + 20) |= add_encimm(dpoff);
 462         pool_write();
 463 }
 464
 465 static long sp_push(int size)
 466 {
 467         sp += size;
 468         if (sp > maxsp)
 469                 maxsp = sp;
 470         return sp;
 471 }
 472
 473 static void tmp_mem(struct tmp *tmp)
 474 {
 475         int src = tmp->addr;
 476         if (!(tmp->loc == LOC_REG))
 477                 return;
 478         if (tmpsp == -1)
 479                 tmpsp = sp;
 480         tmp->addr = -sp_push(LONGSZ);
 481         i_ldr(0, src, REG_FP, tmp->addr, LONGSZ);
 482         regs[src] = NULL;
 483         tmp->loc = LOC_MEM;
 484 }
 485
 486 static void num_cast(struct tmp *t, unsigned bt)
 487 {
 488         if (!(bt & BT_SIGNED) && BT_SZ(bt) != LONGSZ)
 489                 t->addr &= ((1l << (long) (BT_SZ(bt) * 8)) - 1);
 490         if (bt & BT_SIGNED && BT_SZ(bt) != LONGSZ &&
 491                                 t->addr > (1l << (BT_SZ(bt) * 8 - 1)))
 492                 t->addr = -((1l << (BT_SZ(bt) * 8)) - t->addr);
 493 }
 494
 495 static void tmp_reg(struct tmp *tmp, int dst, int deref)
 496 {
 497         int bt = tmp->bt;
 498         if (!tmp->bt)
 499                 deref = 0;
 500         if (deref)
 501                 tmp->bt = 0;
 502         if (tmp->loc == LOC_NUM) {
 503                 i_num(dst, tmp->addr);
 504                 tmp->addr = dst;
 505                 regs[dst] = tmp;
 506                 tmp->loc = LOC_REG;
 507         }
 508         if (tmp->loc == LOC_SYM) {
 509                 i_sym(dst, tmp->sym, tmp->off);
 510                 tmp->addr = dst;
 511                 regs[dst] = tmp;
 512                 tmp->loc = LOC_REG;
 513         }
 514         if (tmp->loc == LOC_REG) {
 515                 if (deref)
 516                         i_ldr(1, dst, tmp->addr, 0, bt);
 517                 else if (dst != tmp->addr)
 518                         i_mov(I_MOV, dst, tmp->addr);
 519                 regs[tmp->addr] = NULL;
 520         }
 521         if (tmp->loc == LOC_LOCAL) {
 522                 if (deref)
 523                         i_ldr(1, dst, REG_FP, tmp->addr + tmp->off, bt);
 524                 else
 525                         i_add_imm(I_ADD, dst, REG_FP, tmp->addr + tmp->off);
 526         }
 527         if (tmp->loc == LOC_MEM) {
 528                 i_ldr(1, dst, REG_FP, tmp->addr, LONGSZ);
 529                 if (deref)
 530                         i_ldr(1, dst, dst, 0, bt);
 531         }
 532         tmp->addr = dst;
 533         regs[dst] = tmp;
 534         tmp->loc = LOC_REG;
 535 }
 536
 537 static void reg_free(int reg)
 538 {
 539         int i;
 540         if (!regs[reg])
 541                 return;
 542         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 543                 if (!regs[tmpregs[i]]) {
 544                         tmp_reg(regs[reg], tmpregs[i], 0);
 545                         return;
 546                 }
 547         tmp_mem(regs[reg]);
 548 }
 549
 550 static void reg_for(int reg, struct tmp *t)
 551 {
 552         if (regs[reg] && regs[reg] != t)
 553                 reg_free(reg);
 554 }
 555
 556 static void tmp_mv(struct tmp *t, int reg)
 557 {
 558         reg_for(reg, t);
 559         tmp_reg(t, reg, 0);
 560 }
 561
 562 static void tmp_to(struct tmp *t, int reg)
 563 {
 564         reg_for(reg, t);
 565         tmp_reg(t, reg, 1);
 566 }
 567
 568 static void tmp_drop(int n)
 569 {
 570         int i;
 571         for (i = ntmp - n; i < ntmp; i++)
 572                 if (tmps[i].loc == LOC_REG)
 573                         regs[tmps[i].addr] = NULL;
 574         ntmp -= n;
 575 }
 576
 577 static void tmp_pop(int reg)
 578 {
 579         struct tmp *t = TMP(0);
 580         tmp_to(t, reg);
 581         tmp_drop(1);
 582 }
 583
 584 static struct tmp *tmp_new(void)
 585 {
 586         return &tmps[ntmp++];
 587 }
 588
 589 static void tmp_push(int reg)
 590 {
 591         struct tmp *t = tmp_new();
 592         t->addr = reg;
 593         t->bt = 0;
 594         t->loc = LOC_REG;
 595         regs[reg] = t;
 596 }
 597
 598 void o_local(long addr)
 599 {
 600         struct tmp *t = tmp_new();
 601         t->addr = -addr;
 602         t->loc = LOC_LOCAL;
 603         t->bt = 0;
 604         t->off = 0;
 605 }
 606
 607 void o_num(long num)
 608 {
 609         struct tmp *t = tmp_new();
 610         t->addr = num;
 611         t->bt = 0;
 612         t->loc = LOC_NUM;
 613 }
 614
 615 void o_sym(char *name)
 616 {
 617         struct tmp *t = tmp_new();
 618         strcpy(t->sym, name);
 619         t->loc = LOC_SYM;
 620         t->bt = 0;
 621         t->off = 0;
 622 }
 623
 624 void o_tmpdrop(int n)
 625 {
 626         if (n == -1 || n > ntmp)
 627                 n = ntmp;
 628         tmp_drop(n);
 629         if (!ntmp) {
 630                 if (tmpsp != -1)
 631                         sp = tmpsp;
 632                 tmpsp = -1;
 633         }
 634 }
 635
 636 #define FORK_REG                0x00
 637
 638 /* make sure tmps remain intact after a conditional expression */
 639 void o_fork(void)
 640 {
 641         int i;
 642         for (i = 0; i < ntmp - 1; i++)
 643                 tmp_mem(&tmps[i]);
 644 }
 645
 646 void o_forkpush(void)
 647 {
 648         tmp_pop(FORK_REG);
 649 }
 650
 651 void o_forkjoin(void)
 652 {
 653         tmp_push(FORK_REG);
 654 }
 655
 656 void o_tmpswap(void)
 657 {
 658         struct tmp *t1 = TMP(0);
 659         struct tmp *t2 = TMP(1);
 660         struct tmp t;
 661         memcpy(&t, t1, sizeof(t));
 662         memcpy(t1, t2, sizeof(t));
 663         memcpy(t2, &t, sizeof(t));
 664         if (t1->loc == LOC_REG)
 665                 regs[t1->addr] = t1;
 666         if (t2->loc == LOC_REG)
 667                 regs[t2->addr] = t2;
 668 }
 669
 670 static int reg_get(int mask)
 671 {
 672         int i;
 673         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 674                 if ((1 << tmpregs[i]) & mask && !regs[tmpregs[i]])
 675                         return tmpregs[i];
 676         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 677                 if ((1 << tmpregs[i]) & mask) {
 678                         reg_free(tmpregs[i]);
 679                         return tmpregs[i];
 680                 }
 681         return 0;
 682 }
 683
 684 static int reg_fortmp(struct tmp *t, int notmask)
 685 {
 686        if (t->loc == LOC_REG && !(notmask & (1 << t->addr)))
 687                return t->addr;
 688        return reg_get(~notmask);
 689 }
 690
 691 static void tmp_copy(struct tmp *t1)
 692 {
 693         struct tmp *t2 = tmp_new();
 694         memcpy(t2, t1, sizeof(*t1));
 695         if (!(t1->loc & (LOC_REG | LOC_MEM)))
 696                 return;
 697         if (t1->loc == LOC_MEM) {
 698                 tmp_mv(t2, reg_get(~0));
 699         } else if (t1->loc == LOC_REG) {
 700                 t2->addr = reg_fortmp(t2, 1 << t1->addr);
 701                 i_mov(I_MOV, t2->addr, t1->addr);
 702                 regs[t2->addr] = t2;
 703         }
 704 }
 705
 706 void o_tmpcopy(void)
 707 {
 708         tmp_copy(TMP(0));
 709 }
 710
 711 void o_cast(unsigned bt)
 712 {
 713         struct tmp *t = TMP(0);
 714         if (!t->bt && t->loc == LOC_NUM) {
 715                 num_cast(t, bt);
 716                 return;
 717         }
 718         if (BT_SZ(bt) != LONGSZ) {
 719                 int reg = reg_fortmp(t, 0);
 720                 tmp_to(t, reg);
 721                 if (bt & BT_SIGNED)
 722                         i_sx(reg, BT_SZ(bt) * 8);
 723                 else
 724                         i_zx(reg, BT_SZ(bt) * 8);
 725         }
 726 }
 727
 728 void o_func_beg(char *name, int global)
 729 {
 730         out_sym(name, (global ? OUT_GLOB : 0) | OUT_CS, cslen, 0);
 731         i_prolog();
 732         sp = 0;
 733         maxsp = sp;
 734         ntmp = 0;
 735         tmpsp = -1;
 736         nret = 0;
 737         memset(regs, 0, sizeof(regs));
 738 }
 739
 740 void o_deref(unsigned bt)
 741 {
 742         struct tmp *t = TMP(0);
 743         if (t->bt)
 744                 tmp_to(t, reg_fortmp(t, 0));
 745         t->bt = bt;
 746 }
 747
 748 void o_load(void)
 749 {
 750         struct tmp *t = TMP(0);
 751         tmp_to(t, reg_fortmp(t, 0));
 752 }
 753
 754 #define TMP_NUM(t)      ((t)->loc == LOC_NUM && !(t)->bt)
 755 #define LOCAL_PTR(t)    ((t)->loc == LOC_LOCAL && !(t)->bt)
 756 #define SYM_PTR(t)      ((t)->loc == LOC_SYM && !(t)->bt)
 757
 758 int o_popnum(long *c)
 759 {
 760         struct tmp *t = TMP(0);
 761         if (!TMP_NUM(t))
 762                 return 1;
 763         *c = t->addr;
 764         tmp_drop(1);
 765         return 0;
 766 }
 767
 768 void o_ret(int rets)
 769 {
 770         if (rets)
 771                 tmp_pop(REG_RET);
 772         else
 773                 i_num(REG_RET, 0);
 774         ret[nret++] = o_jmp(0);
 775 }
 776
 777 void o_func_end(void)
 778 {
 779         int i;
 780         for (i = 0; i < nret; i++)
 781                 o_filljmp(ret[i]);
 782         i_epilog();
 783 }
 784
 785 long o_mklocal(int size)
 786 {
 787         return sp_push(ALIGN(size, LONGSZ));
 788 }
 789
 790 void o_rmlocal(long addr, int sz)
 791 {
 792         sp = addr - sz;
 793 }
 794
 795 long o_arg(int i)
 796 {
 797         return -(10 + i) << 2;
 798 }
 799
 800 void o_assign(unsigned bt)
 801 {
 802         struct tmp *t1 = TMP(0);
 803         struct tmp *t2 = TMP(1);
 804         int r1 = reg_fortmp(t1, 0);
 805         int r2 = reg_fortmp(t2, 1 << r1);
 806         int off = 0;
 807         tmp_to(t1, r1);
 808         if (t2->bt)
 809                 tmp_to(t2, r2);
 810         if (t2->loc == LOC_LOCAL) {
 811                 r2 = REG_FP;
 812                 off = t2->addr + t2->off;
 813         } else {
 814                 tmp_to(t2, r2);
 815         }
 816         tmp_drop(2);
 817         i_ldr(0, r1, r2, off, bt);
 818         tmp_push(r1);
 819 }
 820
 821 static long cu(int op, long i)
 822 {
 823         switch (op & 0xff) {
 824         case O_NEG:
 825                 return -i;
 826         case O_NOT:
 827                 return ~i;
 828         case O_LNOT:
 829                 return !i;
 830         }
 831         return 0;
 832 }
 833
 834 static int c_uop(int op)
 835 {
 836         struct tmp *t1 = TMP(0);
 837         if (!TMP_NUM(t1))
 838                 return 1;
 839         tmp_drop(1);
 840         o_num(cu(op, t1->addr));
 841         return 0;
 842 }
 843
 844 static long cb(int op, long a, long b)
 845 {
 846         switch (op & 0xff) {
 847         case O_ADD:
 848                 return a + b;
 849         case O_SUB:
 850                 return a - b;
 851         case O_AND:
 852                 return a & b;
 853         case O_OR:
 854                 return a | b;
 855         case O_XOR:
 856                 return a ^ b;
 857         case O_MUL:
 858                 return a * b;
 859         case O_DIV:
 860                 return a / b;
 861         case O_MOD:
 862                 return a % b;
 863         case O_SHL:
 864                 return a << b;
 865         case O_SHR:
 866                 if (op & O_SIGNED)
 867                         return a >> b;
 868                 else
 869                         return (unsigned long) a >> b;
 870         case O_LT:
 871                 return a < b;
 872         case O_GT:
 873                 return a > b;
 874         case O_LE:
 875                 return a <= b;
 876         case O_GE:
 877                 return a >= b;
 878         case O_EQ:
 879                 return a == b;
 880         case O_NEQ:
 881                 return a != b;
 882         }
 883         return 0;
 884 }
 885
 886 static int c_bop(int op)
 887 {
 888         struct tmp *t1 = TMP(0);
 889         struct tmp *t2 = TMP(1);
 890         int locals = LOCAL_PTR(t1) + LOCAL_PTR(t2);
 891         int syms = SYM_PTR(t1) + SYM_PTR(t2);
 892         int nums = TMP_NUM(t1) + TMP_NUM(t2);
 893         if (syms + locals == 2 || syms + nums + locals != 2)
 894                 return 1;
 895         if (nums == 1)
 896                 if ((op & 0xff) != O_ADD && ((op & 0xff) != O_SUB || TMP_NUM(t2)))
 897                         return 1;
 898         if (nums == 1) {
 899                 long o1 = TMP_NUM(t1) ? t1->addr : t1->off;
 900                 long o2 = TMP_NUM(t2) ? t2->addr : t2->off;
 901                 long ret = cb(op, o2, o1);
 902                 if (!TMP_NUM(t1))
 903                         o_tmpswap();
 904                 t2->off = ret;
 905                 tmp_drop(1);
 906         } else {
 907                 long ret = cb(op, t2->addr, t1->addr);
 908                 tmp_drop(2);
 909                 o_num(ret);
 910         }
 911         return 0;
 912 }
 913
 914 void o_uop(int op)
 915 {
 916         int r1 = reg_fortmp(TMP(0), 0);
 917         if (!c_uop(op))
 918                 return;
 919         tmp_to(TMP(0), r1);
 920         switch (op & 0xff) {
 921         case O_NEG:
 922                 i_neg(r1);
 923                 break;
 924         case O_NOT:
 925                 i_not(r1);
 926                 break;
 927         case O_LNOT:
 928                 i_lnot(r1);
 929                 break;
 930         }
 931 }
 932
 933 static void bin_regs(int *r1, int *r2)
 934 {
 935         struct tmp *t2 = TMP(0);
 936         struct tmp *t1 = TMP(1);
 937         *r2 = reg_fortmp(t2, 0);
 938         tmp_to(t2, *r2);
 939         *r1 = reg_fortmp(t1, 1 << *r2);
 940         tmp_pop(*r2);
 941         tmp_pop(*r1);
 942 }
 943
 944 static void bin_add(int op)
 945 {
 946         /* opcode for O_ADD, O_SUB, O_AND, O_OR, O_XOR */
 947         static int rx[] = {I_ADD, I_SUB, I_AND, I_ORR, I_EOR};
 948         int r1, r2;
 949         bin_regs(&r1, &r2);
 950         i_add(rx[op & 0x0f], r1, r1, r2);
 951         tmp_push(r1);
 952 }
 953
 954 static void bin_shx(int op)
 955 {
 956         int sm = SM_LSL;
 957         int r1, r2;
 958         bin_regs(&r1, &r2);
 959         if ((op & 0x0f) == 1)
 960                 sm = op & O_SIGNED ? SM_ASR : SM_LSR;
 961         i_shl(sm, r1, r1, r2);
 962         tmp_push(r1);
 963 }
 964
 965 static int log2a(unsigned long n)
 966 {
 967         int i = 0;
 968         for (i = 0; i < LONGSZ * 8; i++)
 969                 if (n & (1u << i))
 970                         break;
 971         if (i == LONGSZ * 8 || !(n >> (i + 1)))
 972                 return i;
 973         return -1;
 974 }
 975
 976 /* optimized version of mul/div/mod for powers of two */
 977 static int mul_2(int op)
 978 {
 979         struct tmp *t1 = TMP(0);
 980         struct tmp *t2 = TMP(1);
 981         long n;
 982         int r2;
 983         int p;
 984         if ((op & 0xff) == O_MUL && t2->loc == LOC_NUM && !t2->bt)
 985                 o_tmpswap();
 986         if (t1->loc != LOC_NUM || t1->bt)
 987                 return 1;
 988         n = t1->addr;
 989         p = log2a(n);
 990         if (n && p == -1)
 991                 return 1;
 992         if ((op & 0xff) == O_MUL) {
 993                 tmp_drop(1);
 994                 if (n == 1)
 995                         return 0;
 996                 if (n == 0) {
 997                         tmp_drop(1);
 998                         o_num(0);
 999                         return 0;
1000                 }
1001                 r2 = reg_fortmp(t2, 0);
1002                 tmp_to(t2, r2);
1003                 i_shl_imm(SM_LSL, r2, p);
1004                 return 0;
1005         }
1006         if (op == O_DIV) {
1007                 tmp_drop(1);
1008                 if (n == 1)
1009                         return 0;
1010                 r2 = reg_fortmp(t2, 0);
1011                 tmp_to(t2, r2);
1012                 i_shl_imm(op & O_SIGNED ? SM_ASR : SM_LSR, r2, p);
1013                 return 0;
1014         }
1015         if (op == O_MOD) {
1016                 tmp_drop(1);
1017                 if (n == 1) {
1018                         tmp_drop(1);
1019                         o_num(0);
1020                         return 0;
1021                 }
1022                 r2 = reg_fortmp(t2, 0);
1023                 tmp_to(t2, r2);
1024                 i_zx(r2, p);
1025                 return 0;
1026         }
1027         return 1;
1028 }
1029
1030 static void bin_div(int op)
1031 {
1032         struct tmp *t2 = TMP(0);
1033         struct tmp *t1 = TMP(1);
1034         char *func;
1035         int i;
1036         putdiv = 1;
1037         if ((op & 0xff) == O_DIV)
1038                 func = op & O_SIGNED ? "__divdi3" : "__udivdi3";
1039         else
1040                 func = op & O_SIGNED ? "__moddi3" : "__umoddi3";
1041         for (i = 0; i < ARRAY_SIZE(argregs); i++)
1042                 if (regs[argregs[i]] && regs[argregs[i]] - tmps < ntmp - 2)
1043                         tmp_mem(regs[argregs[i]]);
1044         tmp_to(t1, argregs[0]);
1045         tmp_to(t2, argregs[1]);
1046         tmp_drop(2);
1047         i_call(func);
1048         tmp_push(REG_RET);
1049 }
1050
1051 static void bin_mul(int op)
1052 {
1053         int r1, r2;
1054         if (!mul_2(op))
1055                 return;
1056         if ((op & 0xff) == O_DIV || (op & 0xff) == O_MOD) {
1057                 bin_div(op);
1058         } else {
1059                 bin_regs(&r1, &r2);
1060                 i_mul(r1, r1, r2);
1061                 tmp_push(r1);
1062         }
1063 }
1064
1065 static void bin_cmp(int op)
1066 {
1067         /* lt, gt, le, ge, eq, neq */
1068         static int ucond[] = {3, 8, 9, 2, 0, 1};
1069         static int scond[] = {11, 12, 13, 10, 0, 1};
1070         int r1, r2;
1071         bin_regs(&r1, &r2);
1072         i_cmp(I_CMP, r1, r2);
1073         i_set(op & O_SIGNED ? scond[op & 0x0f] : ucond[op & 0x0f], r1);
1074         tmp_push(r1);
1075 }
1076
1077 void o_bop(int op)
1078 {
1079         if (!c_bop(op))
1080                 return;
1081         if ((op & 0xf0) == 0x00)
1082                 bin_add(op);
1083         if ((op & 0xf0) == 0x10)
1084                 bin_shx(op);
1085         if ((op & 0xf0) == 0x20)
1086                 bin_mul(op);
1087         if ((op & 0xf0) == 0x30)
1088                 bin_cmp(op);
1089 }
1090
1091 static void load_regs2(int *r0, int *r1, int *r2)
1092 {
1093         struct tmp *t0 = TMP(0);
1094         struct tmp *t1 = TMP(1);
1095         struct tmp *t2 = TMP(2);
1096         *r0 = reg_fortmp(t0, 0);
1097         *r1 = reg_fortmp(t1, 1 << *r0);
1098         *r2 = reg_fortmp(t2, (1 << *r0) | (1 << *r1));
1099         tmp_to(t0, *r0);
1100         tmp_to(t1, *r1);
1101         tmp_to(t2, *r2);
1102 }
1103
1104 void o_memcpy(void)
1105 {
1106         int rd, rs, rn;
1107         load_regs2(&rn, &rs, &rd);
1108         i_memcpy(rd, rs, rn);
1109         tmp_drop(2);
1110 }
1111
1112 void o_memset(void)
1113 {
1114         int rd, rs, rn;
1115         load_regs2(&rn, &rs, &rd);
1116         i_memset(rd, rs, rn);
1117         tmp_drop(2);
1118 }
1119
1120 long o_mklabel(void)
1121 {
1122         return cslen;
1123 }
1124
1125 static long jxz(long addr, int z)
1126 {
1127         int r = reg_fortmp(TMP(0), 0);
1128         tmp_pop(r);
1129         i_b_if(addr, r, z);
1130         return cslen - 4;
1131 }
1132
1133 long o_jz(long addr)
1134 {
1135         return jxz(addr, 1);
1136 }
1137
1138 long o_jnz(long addr)
1139 {
1140         return jxz(addr, 0);
1141 }
1142
1143 long o_jmp(long addr)
1144 {
1145         i_b(addr);
1146         return cslen - 4;
1147 }
1148
1149 void o_filljmp2(long addr, long jmpdst)
1150 {
1151         i_b_fill((void *) cs + addr, jmpdst - addr);
1152 }
1153
1154 void o_filljmp(long addr)
1155 {
1156         o_filljmp2(addr, cslen);
1157 }
1158
1159 void o_call(int argc, int rets)
1160 {
1161         struct tmp *t;
1162         int i;
1163         int aregs = MIN(ARRAY_SIZE(argregs), argc);
1164         for (i = 0; i < ARRAY_SIZE(argregs); i++)
1165                 if (regs[argregs[i]] && regs[argregs[i]] - tmps < ntmp - argc)
1166                         tmp_mem(regs[argregs[i]]);
1167         if (argc > aregs) {
1168                 sp_push(LONGSZ * (argc - aregs));
1169                 for (i = argc - 1; i >= aregs; --i) {
1170                         int reg = reg_fortmp(TMP(0), 0);
1171                         tmp_pop(reg);
1172                         i_ldr(0, reg, REG_SP, (i - aregs) * LONGSZ, LONGSZ);
1173                 }
1174         }
1175         for (i = aregs - 1; i >= 0; --i)
1176                 tmp_to(TMP(aregs - i - 1), argregs[i]);
1177         tmp_drop(aregs);
1178         t = TMP(0);
1179         if (t->loc == LOC_SYM && !t->bt) {
1180                 i_call(t->sym);
1181                 tmp_drop(1);
1182         } else {
1183                 int reg = t->loc == LOC_REG ? t->addr : REG_TMP;
1184                 tmp_pop(reg);
1185                 i_call_reg(reg);
1186         }
1187         if (rets)
1188                 tmp_push(REG_RET);
1189 }
1190
1191 void o_nogen(void)
1192 {
1193         nogen++;
1194 }
1195
1196 void o_dogen(void)
1197 {
1198         nogen--;
1199 }
1200
1201 void dat_bss(char *name, int size, int global)
1202 {
1203         out_sym(name, OUT_BSS | (global ? OUT_GLOB : 0), bsslen, size);
1204         bsslen += ALIGN(size, LONGSZ);
1205 }
1206
1207 #define MAXDATS         (1 << 10)
1208 static char dat_names[MAXDATS][NAMELEN];
1209 static int dat_offs[MAXDATS];
1210 static int ndats;
1211
1212 void err(char *msg);
1213 void *dat_dat(char *name, int size, int global)
1214 {
1215         void *addr = ds + dslen;
1216         int idx = ndats++;
1217         if (idx >= MAXDATS)
1218                 err("nomem: MAXDATS reached!\n");
1219         strcpy(dat_names[idx], name);
1220         dat_offs[idx] = dslen;
1221         out_sym(name, OUT_DS | (global ? OUT_GLOB : 0), dslen, size);
1222         dslen += ALIGN(size, LONGSZ);
1223         return addr;
1224 }
1225
1226 static int dat_off(char *name)
1227 {
1228         int i;
1229         for (i = 0; i < ndats; i++)
1230                 if (!strcmp(name, dat_names[i]))
1231                         return dat_offs[i];
1232         return 0;
1233 }
1234
1235 void o_datset(char *name, int off, unsigned bt)
1236 {
1237         struct tmp *t = TMP(0);
1238         int sym_off = dat_off(name) + off;
1239         if (t->loc == LOC_NUM && !t->bt) {
1240                 num_cast(t, bt);
1241                 memcpy(ds + sym_off, &t->addr, BT_SZ(bt));
1242         }
1243         if (t->loc == LOC_SYM && !t->bt) {
1244                 out_rel(t->sym, OUT_DS, sym_off);
1245                 memcpy(ds + sym_off, &t->off, BT_SZ(bt));
1246         }
1247         tmp_drop(1);
1248 }
1249
1250 /* compiled division functions; div.s contains the source */
1251 static int udivdi3[] = {
1252         0xe3a02000, 0xe3a03000, 0xe1110001, 0x0a00000a,
1253         0xe1b0c211, 0xe2822001, 0x5afffffc, 0xe3a0c001,
1254         0xe2522001, 0x4a000004, 0xe1500211, 0x3afffffb,
1255         0xe0400211, 0xe083321c, 0xeafffff8, 0xe1a01000,
1256         0xe1a00003, 0xe1a0f00e,
1257 };
1258 static int umoddi3[] = {
1259         0xe92d4000, 0xebffffeb, 0xe1a00001, 0xe8bd8000,
1260 };
1261 static int divdi3[] = {
1262         0xe92d4030, 0xe1a04000, 0xe1a05001, 0xe1100000,
1263         0x42600000, 0xe1110001, 0x42611000, 0xebffffe1,
1264         0xe1340005, 0x42600000, 0xe1140004, 0x42611000,
1265         0xe8bd8030,
1266 };
1267 static int moddi3[] = {
1268         0xe92d4000, 0xebfffff0, 0xe1a00001, 0xe8bd8000,
1269 };
1270
1271 void o_write(int fd)
1272 {
1273         if (putdiv) {
1274                 out_sym("__udivdi3", OUT_CS, cslen, 0);
1275                 os(udivdi3, sizeof(udivdi3));
1276                 out_sym("__umoddi3", OUT_CS, cslen, 0);
1277                 os(umoddi3, sizeof(umoddi3));
1278                 out_sym("__divdi3", OUT_CS, cslen, 0);
1279                 os(divdi3, sizeof(divdi3));
1280                 out_sym("__moddi3", OUT_CS, cslen, 0);
1281                 os(moddi3, sizeof(moddi3));
1282         }
1283         out_write(fd, cs, cslen, ds, dslen);
1284 }