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         if (nret && ret[nret - 1] == cslen - 4) {
 781                 cslen -= 4;
 782                 nret--;
 783         }
 784         for (i = 0; i < nret; i++)
 785                 o_filljmp(ret[i]);
 786         i_epilog();
 787 }
 788
 789 long o_mklocal(int size)
 790 {
 791         return sp_push(ALIGN(size, LONGSZ));
 792 }
 793
 794 void o_rmlocal(long addr, int sz)
 795 {
 796         sp = addr - sz;
 797 }
 798
 799 long o_arg(int i)
 800 {
 801         return -(10 + i) << 2;
 802 }
 803
 804 void o_assign(unsigned bt)
 805 {
 806         struct tmp *t1 = TMP(0);
 807         struct tmp *t2 = TMP(1);
 808         int r1 = reg_fortmp(t1, 0);
 809         int r2 = reg_fortmp(t2, 1 << r1);
 810         int off = 0;
 811         tmp_to(t1, r1);
 812         if (t2->bt)
 813                 tmp_to(t2, r2);
 814         if (t2->loc == LOC_LOCAL) {
 815                 r2 = REG_FP;
 816                 off = t2->addr + t2->off;
 817         } else {
 818                 tmp_to(t2, r2);
 819         }
 820         tmp_drop(2);
 821         i_ldr(0, r1, r2, off, bt);
 822         tmp_push(r1);
 823 }
 824
 825 static long cu(int op, long i)
 826 {
 827         switch (op & 0xff) {
 828         case O_NEG:
 829                 return -i;
 830         case O_NOT:
 831                 return ~i;
 832         case O_LNOT:
 833                 return !i;
 834         }
 835         return 0;
 836 }
 837
 838 static int c_uop(int op)
 839 {
 840         struct tmp *t1 = TMP(0);
 841         if (!TMP_NUM(t1))
 842                 return 1;
 843         tmp_drop(1);
 844         o_num(cu(op, t1->addr));
 845         return 0;
 846 }
 847
 848 static long cb(int op, long a, long b)
 849 {
 850         switch (op & 0xff) {
 851         case O_ADD:
 852                 return a + b;
 853         case O_SUB:
 854                 return a - b;
 855         case O_AND:
 856                 return a & b;
 857         case O_OR:
 858                 return a | b;
 859         case O_XOR:
 860                 return a ^ b;
 861         case O_MUL:
 862                 return a * b;
 863         case O_DIV:
 864                 return a / b;
 865         case O_MOD:
 866                 return a % b;
 867         case O_SHL:
 868                 return a << b;
 869         case O_SHR:
 870                 if (op & O_SIGNED)
 871                         return a >> b;
 872                 else
 873                         return (unsigned long) a >> b;
 874         case O_LT:
 875                 return a < b;
 876         case O_GT:
 877                 return a > b;
 878         case O_LE:
 879                 return a <= b;
 880         case O_GE:
 881                 return a >= b;
 882         case O_EQ:
 883                 return a == b;
 884         case O_NEQ:
 885                 return a != b;
 886         }
 887         return 0;
 888 }
 889
 890 static int c_bop(int op)
 891 {
 892         struct tmp *t1 = TMP(0);
 893         struct tmp *t2 = TMP(1);
 894         int locals = LOCAL_PTR(t1) + LOCAL_PTR(t2);
 895         int syms = SYM_PTR(t1) + SYM_PTR(t2);
 896         int nums = TMP_NUM(t1) + TMP_NUM(t2);
 897         if (syms + locals == 2 || syms + nums + locals != 2)
 898                 return 1;
 899         if (nums == 1)
 900                 if ((op & 0xff) != O_ADD && ((op & 0xff) != O_SUB || TMP_NUM(t2)))
 901                         return 1;
 902         if (nums == 1) {
 903                 long o1 = TMP_NUM(t1) ? t1->addr : t1->off;
 904                 long o2 = TMP_NUM(t2) ? t2->addr : t2->off;
 905                 long ret = cb(op, o2, o1);
 906                 if (!TMP_NUM(t1))
 907                         o_tmpswap();
 908                 t2->off = ret;
 909                 tmp_drop(1);
 910         } else {
 911                 long ret = cb(op, t2->addr, t1->addr);
 912                 tmp_drop(2);
 913                 o_num(ret);
 914         }
 915         return 0;
 916 }
 917
 918 void o_uop(int op)
 919 {
 920         int r1 = reg_fortmp(TMP(0), 0);
 921         if (!c_uop(op))
 922                 return;
 923         tmp_to(TMP(0), r1);
 924         switch (op & 0xff) {
 925         case O_NEG:
 926                 i_neg(r1);
 927                 break;
 928         case O_NOT:
 929                 i_not(r1);
 930                 break;
 931         case O_LNOT:
 932                 i_lnot(r1);
 933                 break;
 934         }
 935 }
 936
 937 static void bin_regs(int *r1, int *r2)
 938 {
 939         struct tmp *t2 = TMP(0);
 940         struct tmp *t1 = TMP(1);
 941         *r2 = reg_fortmp(t2, 0);
 942         tmp_to(t2, *r2);
 943         *r1 = reg_fortmp(t1, 1 << *r2);
 944         tmp_pop(*r2);
 945         tmp_pop(*r1);
 946 }
 947
 948 static void bin_add(int op)
 949 {
 950         /* opcode for O_ADD, O_SUB, O_AND, O_OR, O_XOR */
 951         static int rx[] = {I_ADD, I_SUB, I_AND, I_ORR, I_EOR};
 952         int r1, r2;
 953         bin_regs(&r1, &r2);
 954         i_add(rx[op & 0x0f], r1, r1, r2);
 955         tmp_push(r1);
 956 }
 957
 958 static void bin_shx(int op)
 959 {
 960         int sm = SM_LSL;
 961         int r1, r2;
 962         bin_regs(&r1, &r2);
 963         if ((op & 0x0f) == 1)
 964                 sm = op & O_SIGNED ? SM_ASR : SM_LSR;
 965         i_shl(sm, r1, r1, r2);
 966         tmp_push(r1);
 967 }
 968
 969 static int log2a(unsigned long n)
 970 {
 971         int i = 0;
 972         for (i = 0; i < LONGSZ * 8; i++)
 973                 if (n & (1u << i))
 974                         break;
 975         if (i == LONGSZ * 8 || !(n >> (i + 1)))
 976                 return i;
 977         return -1;
 978 }
 979
 980 /* optimized version of mul/div/mod for powers of two */
 981 static int mul_2(int op)
 982 {
 983         struct tmp *t1 = TMP(0);
 984         struct tmp *t2 = TMP(1);
 985         long n;
 986         int r2;
 987         int p;
 988         if ((op & 0xff) == O_MUL && t2->loc == LOC_NUM && !t2->bt)
 989                 o_tmpswap();
 990         if (t1->loc != LOC_NUM || t1->bt)
 991                 return 1;
 992         n = t1->addr;
 993         p = log2a(n);
 994         if (n && p == -1)
 995                 return 1;
 996         if ((op & 0xff) == O_MUL) {
 997                 tmp_drop(1);
 998                 if (n == 1)
 999                         return 0;
1000                 if (n == 0) {
1001                         tmp_drop(1);
1002                         o_num(0);
1003                         return 0;
1004                 }
1005                 r2 = reg_fortmp(t2, 0);
1006                 tmp_to(t2, r2);
1007                 i_shl_imm(SM_LSL, r2, p);
1008                 return 0;
1009         }
1010         if (op == O_DIV) {
1011                 tmp_drop(1);
1012                 if (n == 1)
1013                         return 0;
1014                 r2 = reg_fortmp(t2, 0);
1015                 tmp_to(t2, r2);
1016                 i_shl_imm(op & O_SIGNED ? SM_ASR : SM_LSR, r2, p);
1017                 return 0;
1018         }
1019         if (op == O_MOD) {
1020                 tmp_drop(1);
1021                 if (n == 1) {
1022                         tmp_drop(1);
1023                         o_num(0);
1024                         return 0;
1025                 }
1026                 r2 = reg_fortmp(t2, 0);
1027                 tmp_to(t2, r2);
1028                 i_zx(r2, p);
1029                 return 0;
1030         }
1031         return 1;
1032 }
1033
1034 static void bin_div(int op)
1035 {
1036         struct tmp *t2 = TMP(0);
1037         struct tmp *t1 = TMP(1);
1038         char *func;
1039         int i;
1040         putdiv = 1;
1041         if ((op & 0xff) == O_DIV)
1042                 func = op & O_SIGNED ? "__divdi3" : "__udivdi3";
1043         else
1044                 func = op & O_SIGNED ? "__moddi3" : "__umoddi3";
1045         for (i = 0; i < ARRAY_SIZE(argregs); i++)
1046                 if (regs[argregs[i]] && regs[argregs[i]] - tmps < ntmp - 2)
1047                         tmp_mem(regs[argregs[i]]);
1048         tmp_to(t1, argregs[0]);
1049         tmp_to(t2, argregs[1]);
1050         tmp_drop(2);
1051         i_call(func);
1052         tmp_push(REG_RET);
1053 }
1054
1055 static void bin_mul(int op)
1056 {
1057         int r1, r2;
1058         if (!mul_2(op))
1059                 return;
1060         if ((op & 0xff) == O_DIV || (op & 0xff) == O_MOD) {
1061                 bin_div(op);
1062         } else {
1063                 bin_regs(&r1, &r2);
1064                 i_mul(r1, r1, r2);
1065                 tmp_push(r1);
1066         }
1067 }
1068
1069 static void bin_cmp(int op)
1070 {
1071         /* lt, gt, le, ge, eq, neq */
1072         static int ucond[] = {3, 8, 9, 2, 0, 1};
1073         static int scond[] = {11, 12, 13, 10, 0, 1};
1074         int r1, r2;
1075         bin_regs(&r1, &r2);
1076         i_cmp(I_CMP, r1, r2);
1077         i_set(op & O_SIGNED ? scond[op & 0x0f] : ucond[op & 0x0f], r1);
1078         tmp_push(r1);
1079 }
1080
1081 void o_bop(int op)
1082 {
1083         if (!c_bop(op))
1084                 return;
1085         if ((op & 0xf0) == 0x00)
1086                 bin_add(op);
1087         if ((op & 0xf0) == 0x10)
1088                 bin_shx(op);
1089         if ((op & 0xf0) == 0x20)
1090                 bin_mul(op);
1091         if ((op & 0xf0) == 0x30)
1092                 bin_cmp(op);
1093 }
1094
1095 static void load_regs2(int *r0, int *r1, int *r2)
1096 {
1097         struct tmp *t0 = TMP(0);
1098         struct tmp *t1 = TMP(1);
1099         struct tmp *t2 = TMP(2);
1100         *r0 = reg_fortmp(t0, 0);
1101         *r1 = reg_fortmp(t1, 1 << *r0);
1102         *r2 = reg_fortmp(t2, (1 << *r0) | (1 << *r1));
1103         tmp_to(t0, *r0);
1104         tmp_to(t1, *r1);
1105         tmp_to(t2, *r2);
1106 }
1107
1108 void o_memcpy(void)
1109 {
1110         int rd, rs, rn;
1111         load_regs2(&rn, &rs, &rd);
1112         i_memcpy(rd, rs, rn);
1113         tmp_drop(2);
1114 }
1115
1116 void o_memset(void)
1117 {
1118         int rd, rs, rn;
1119         load_regs2(&rn, &rs, &rd);
1120         i_memset(rd, rs, rn);
1121         tmp_drop(2);
1122 }
1123
1124 long o_mklabel(void)
1125 {
1126         return cslen;
1127 }
1128
1129 static long jxz(long addr, int z)
1130 {
1131         int r = reg_fortmp(TMP(0), 0);
1132         tmp_pop(r);
1133         i_b_if(addr, r, z);
1134         return cslen - 4;
1135 }
1136
1137 long o_jz(long addr)
1138 {
1139         return jxz(addr, 1);
1140 }
1141
1142 long o_jnz(long addr)
1143 {
1144         return jxz(addr, 0);
1145 }
1146
1147 long o_jmp(long addr)
1148 {
1149         i_b(addr);
1150         return cslen - 4;
1151 }
1152
1153 void o_filljmp2(long addr, long jmpdst)
1154 {
1155         i_b_fill((void *) cs + addr, jmpdst - addr);
1156 }
1157
1158 void o_filljmp(long addr)
1159 {
1160         o_filljmp2(addr, cslen);
1161 }
1162
1163 void o_call(int argc, int rets)
1164 {
1165         struct tmp *t;
1166         int i;
1167         int aregs = MIN(ARRAY_SIZE(argregs), argc);
1168         for (i = 0; i < ARRAY_SIZE(argregs); i++)
1169                 if (regs[argregs[i]] && regs[argregs[i]] - tmps < ntmp - argc)
1170                         tmp_mem(regs[argregs[i]]);
1171         if (argc > aregs) {
1172                 sp_push(LONGSZ * (argc - aregs));
1173                 for (i = argc - 1; i >= aregs; --i) {
1174                         int reg = reg_fortmp(TMP(0), 0);
1175                         tmp_pop(reg);
1176                         i_ldr(0, reg, REG_SP, (i - aregs) * LONGSZ, LONGSZ);
1177                 }
1178         }
1179         for (i = aregs - 1; i >= 0; --i)
1180                 tmp_to(TMP(aregs - i - 1), argregs[i]);
1181         tmp_drop(aregs);
1182         t = TMP(0);
1183         if (t->loc == LOC_SYM && !t->bt) {
1184                 i_call(t->sym);
1185                 tmp_drop(1);
1186         } else {
1187                 int reg = t->loc == LOC_REG ? t->addr : REG_TMP;
1188                 tmp_pop(reg);
1189                 i_call_reg(reg);
1190         }
1191         if (rets)
1192                 tmp_push(REG_RET);
1193 }
1194
1195 void o_nogen(void)
1196 {
1197         nogen++;
1198 }
1199
1200 void o_dogen(void)
1201 {
1202         nogen--;
1203 }
1204
1205 void dat_bss(char *name, int size, int global)
1206 {
1207         out_sym(name, OUT_BSS | (global ? OUT_GLOB : 0), bsslen, size);
1208         bsslen += ALIGN(size, LONGSZ);
1209 }
1210
1211 #define MAXDATS         (1 << 10)
1212 static char dat_names[MAXDATS][NAMELEN];
1213 static int dat_offs[MAXDATS];
1214 static int ndats;
1215
1216 void err(char *msg);
1217 void *dat_dat(char *name, int size, int global)
1218 {
1219         void *addr = ds + dslen;
1220         int idx = ndats++;
1221         if (idx >= MAXDATS)
1222                 err("nomem: MAXDATS reached!\n");
1223         strcpy(dat_names[idx], name);
1224         dat_offs[idx] = dslen;
1225         out_sym(name, OUT_DS | (global ? OUT_GLOB : 0), dslen, size);
1226         dslen += ALIGN(size, LONGSZ);
1227         return addr;
1228 }
1229
1230 static int dat_off(char *name)
1231 {
1232         int i;
1233         for (i = 0; i < ndats; i++)
1234                 if (!strcmp(name, dat_names[i]))
1235                         return dat_offs[i];
1236         return 0;
1237 }
1238
1239 void o_datset(char *name, int off, unsigned bt)
1240 {
1241         struct tmp *t = TMP(0);
1242         int sym_off = dat_off(name) + off;
1243         if (t->loc == LOC_NUM && !t->bt) {
1244                 num_cast(t, bt);
1245                 memcpy(ds + sym_off, &t->addr, BT_SZ(bt));
1246         }
1247         if (t->loc == LOC_SYM && !t->bt) {
1248                 out_rel(t->sym, OUT_DS, sym_off);
1249                 memcpy(ds + sym_off, &t->off, BT_SZ(bt));
1250         }
1251         tmp_drop(1);
1252 }
1253
1254 /* compiled division functions; div.s contains the source */
1255 static int udivdi3[] = {
1256         0xe3a02000, 0xe3a03000, 0xe1110001, 0x0a00000a,
1257         0xe1b0c211, 0xe2822001, 0x5afffffc, 0xe3a0c001,
1258         0xe2522001, 0x4a000004, 0xe1500211, 0x3afffffb,
1259         0xe0400211, 0xe083321c, 0xeafffff8, 0xe1a01000,
1260         0xe1a00003, 0xe1a0f00e,
1261 };
1262 static int umoddi3[] = {
1263         0xe92d4000, 0xebffffeb, 0xe1a00001, 0xe8bd8000,
1264 };
1265 static int divdi3[] = {
1266         0xe92d4030, 0xe1a04000, 0xe1a05001, 0xe1100000,
1267         0x42600000, 0xe1110001, 0x42611000, 0xebffffe1,
1268         0xe1340005, 0x42600000, 0xe1140004, 0x42611000,
1269         0xe8bd8030,
1270 };
1271 static int moddi3[] = {
1272         0xe92d4000, 0xebfffff0, 0xe1a00001, 0xe8bd8000,
1273 };
1274
1275 void o_write(int fd)
1276 {
1277         if (putdiv) {
1278                 out_sym("__udivdi3", OUT_CS, cslen, 0);
1279                 os(udivdi3, sizeof(udivdi3));
1280                 out_sym("__umoddi3", OUT_CS, cslen, 0);
1281                 os(umoddi3, sizeof(umoddi3));
1282                 out_sym("__divdi3", OUT_CS, cslen, 0);
1283                 os(divdi3, sizeof(divdi3));
1284                 out_sym("__moddi3", OUT_CS, cslen, 0);
1285                 os(moddi3, sizeof(moddi3));
1286         }
1287         out_write(fd, cs, cslen, ds, dslen);
1288 }