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, 0, 0, 14) | rd);
 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         last_set = -1;
 401         oi(BL(z ? nots[last_cond] : last_cond, 0, addr - cslen));
 402 }
 403
 404 static void i_b_fill(long *dst, int diff)
 405 {
 406         *dst = (*dst & 0xff000000) | (((diff - 8) >> 2) & 0x00ffffff);
 407 }
 408
 409 static void i_memcpy(int rd, int rs, int rn)
 410 {
 411         oi(ADD(I_SUB, rn, rn, 1, 1, 14) | 1);
 412         oi(BL(4, 0, 16));
 413         oi(LDR(1, REG_TMP, rs, 1, 1, 0, 0) | 1);
 414         oi(LDR(0, REG_TMP, rd, 1, 1, 0, 0) | 1);
 415         oi(BL(14, 0, -16));
 416 }
 417
 418 static void i_memset(int rd, int rs, int rn)
 419 {
 420         oi(ADD(I_SUB, rn, rn, 1, 1, 14) | 1);
 421         oi(BL(4, 0, 12));
 422         oi(LDR(0, rs, rd, 1, 1, 0, 0) | 1);
 423         oi(BL(14, 0, -12));
 424 }
 425
 426 static void i_call_reg(int rd)
 427 {
 428         i_mov(I_MOV, REG_LR, REG_PC);
 429         i_mov(I_MOV, REG_PC, rd);
 430 }
 431
 432 static void i_call(char *sym)
 433 {
 434         if (!nogen)
 435                 out_rel(sym, OUT_CS | OUT_REL24, cslen);
 436         oi(BL(14, 1, 0));
 437 }
 438
 439 static void i_prolog(void)
 440 {
 441         func_beg = cslen;
 442         nums = 0;
 443         oi(0xe1a0c00d);         /* mov   r12, sp */
 444         oi(0xe92d000f);         /* stmfd sp!, {r0-r3} */
 445         oi(0xe92d5ff0);         /* stmfd sp!, {r0-r11, r12, lr} */
 446         oi(0xe1a0b00d);         /* mov   fp, sp */
 447         oi(0xe24dd000);         /* sub   sp, sp, xx */
 448         oi(0xe28fa000);         /* add   dp, pc, xx */
 449 }
 450
 451 static void i_epilog(void)
 452 {
 453         int dpoff;
 454         oi(0xe89baff0);         /* ldmfd fp, {r4-r11, sp, pc} */
 455         dpoff = add_decimm(add_rndimm(add_encimm(cslen - func_beg - 28)));
 456         cslen = func_beg + dpoff + 28;
 457         maxsp = ALIGN(maxsp, 8);
 458         maxsp = add_decimm(add_rndimm(add_encimm(maxsp)));
 459         /* fill stack sub: sp = sp - xx */
 460         *(long *) (cs + func_beg + 16) |= add_encimm(maxsp);
 461         /* fill data ptr addition: dp = pc + xx */
 462         *(long *) (cs + func_beg + 20) |= add_encimm(dpoff);
 463         pool_write();
 464 }
 465
 466 static long sp_push(int size)
 467 {
 468         sp += size;
 469         if (sp > maxsp)
 470                 maxsp = sp;
 471         return sp;
 472 }
 473
 474 static void tmp_mem(struct tmp *tmp)
 475 {
 476         int src = tmp->addr;
 477         if (!(tmp->loc == LOC_REG))
 478                 return;
 479         if (tmpsp == -1)
 480                 tmpsp = sp;
 481         tmp->addr = -sp_push(LONGSZ);
 482         i_ldr(0, src, REG_FP, tmp->addr, LONGSZ);
 483         regs[src] = NULL;
 484         tmp->loc = LOC_MEM;
 485 }
 486
 487 static void num_cast(struct tmp *t, unsigned bt)
 488 {
 489         if (!(bt & BT_SIGNED) && BT_SZ(bt) != LONGSZ)
 490                 t->addr &= ((1l << (long) (BT_SZ(bt) * 8)) - 1);
 491         if (bt & BT_SIGNED && BT_SZ(bt) != LONGSZ &&
 492                                 t->addr > (1l << (BT_SZ(bt) * 8 - 1)))
 493                 t->addr = -((1l << (BT_SZ(bt) * 8)) - t->addr);
 494 }
 495
 496 static void tmp_reg(struct tmp *tmp, int dst, int deref)
 497 {
 498         int bt = tmp->bt;
 499         if (!tmp->bt)
 500                 deref = 0;
 501         if (deref)
 502                 tmp->bt = 0;
 503         if (tmp->loc == LOC_NUM) {
 504                 i_num(dst, tmp->addr);
 505                 tmp->addr = dst;
 506                 regs[dst] = tmp;
 507                 tmp->loc = LOC_REG;
 508         }
 509         if (tmp->loc == LOC_SYM) {
 510                 i_sym(dst, tmp->sym, tmp->off);
 511                 tmp->addr = dst;
 512                 regs[dst] = tmp;
 513                 tmp->loc = LOC_REG;
 514         }
 515         if (tmp->loc == LOC_REG) {
 516                 if (deref)
 517                         i_ldr(1, dst, tmp->addr, 0, bt);
 518                 else if (dst != tmp->addr)
 519                         i_mov(I_MOV, dst, tmp->addr);
 520                 regs[tmp->addr] = NULL;
 521         }
 522         if (tmp->loc == LOC_LOCAL) {
 523                 if (deref)
 524                         i_ldr(1, dst, REG_FP, tmp->addr + tmp->off, bt);
 525                 else
 526                         i_add_imm(I_ADD, dst, REG_FP, tmp->addr + tmp->off);
 527         }
 528         if (tmp->loc == LOC_MEM) {
 529                 i_ldr(1, dst, REG_FP, tmp->addr, LONGSZ);
 530                 if (deref)
 531                         i_ldr(1, dst, dst, 0, bt);
 532         }
 533         tmp->addr = dst;
 534         regs[dst] = tmp;
 535         tmp->loc = LOC_REG;
 536 }
 537
 538 static void reg_free(int reg)
 539 {
 540         int i;
 541         if (!regs[reg])
 542                 return;
 543         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 544                 if (!regs[tmpregs[i]]) {
 545                         tmp_reg(regs[reg], tmpregs[i], 0);
 546                         return;
 547                 }
 548         tmp_mem(regs[reg]);
 549 }
 550
 551 static void reg_for(int reg, struct tmp *t)
 552 {
 553         if (regs[reg] && regs[reg] != t)
 554                 reg_free(reg);
 555 }
 556
 557 static void tmp_mv(struct tmp *t, int reg)
 558 {
 559         reg_for(reg, t);
 560         tmp_reg(t, reg, 0);
 561 }
 562
 563 static void tmp_to(struct tmp *t, int reg)
 564 {
 565         reg_for(reg, t);
 566         tmp_reg(t, reg, 1);
 567 }
 568
 569 static void tmp_drop(int n)
 570 {
 571         int i;
 572         for (i = ntmp - n; i < ntmp; i++)
 573                 if (tmps[i].loc == LOC_REG)
 574                         regs[tmps[i].addr] = NULL;
 575         ntmp -= n;
 576 }
 577
 578 static void tmp_pop(int reg)
 579 {
 580         struct tmp *t = TMP(0);
 581         tmp_to(t, reg);
 582         tmp_drop(1);
 583 }
 584
 585 static struct tmp *tmp_new(void)
 586 {
 587         return &tmps[ntmp++];
 588 }
 589
 590 static void tmp_push(int reg)
 591 {
 592         struct tmp *t = tmp_new();
 593         t->addr = reg;
 594         t->bt = 0;
 595         t->loc = LOC_REG;
 596         regs[reg] = t;
 597 }
 598
 599 void o_local(long addr)
 600 {
 601         struct tmp *t = tmp_new();
 602         t->addr = -addr;
 603         t->loc = LOC_LOCAL;
 604         t->bt = 0;
 605         t->off = 0;
 606 }
 607
 608 void o_num(long num)
 609 {
 610         struct tmp *t = tmp_new();
 611         t->addr = num;
 612         t->bt = 0;
 613         t->loc = LOC_NUM;
 614 }
 615
 616 void o_sym(char *name)
 617 {
 618         struct tmp *t = tmp_new();
 619         strcpy(t->sym, name);
 620         t->loc = LOC_SYM;
 621         t->bt = 0;
 622         t->off = 0;
 623 }
 624
 625 void o_tmpdrop(int n)
 626 {
 627         if (n == -1 || n > ntmp)
 628                 n = ntmp;
 629         tmp_drop(n);
 630         if (!ntmp) {
 631                 if (tmpsp != -1)
 632                         sp = tmpsp;
 633                 tmpsp = -1;
 634         }
 635 }
 636
 637 #define FORK_REG                0x00
 638
 639 /* make sure tmps remain intact after a conditional expression */
 640 void o_fork(void)
 641 {
 642         int i;
 643         for (i = 0; i < ntmp - 1; i++)
 644                 tmp_mem(&tmps[i]);
 645 }
 646
 647 void o_forkpush(void)
 648 {
 649         tmp_pop(FORK_REG);
 650 }
 651
 652 void o_forkjoin(void)
 653 {
 654         tmp_push(FORK_REG);
 655 }
 656
 657 void o_tmpswap(void)
 658 {
 659         struct tmp *t1 = TMP(0);
 660         struct tmp *t2 = TMP(1);
 661         struct tmp t;
 662         memcpy(&t, t1, sizeof(t));
 663         memcpy(t1, t2, sizeof(t));
 664         memcpy(t2, &t, sizeof(t));
 665         if (t1->loc == LOC_REG)
 666                 regs[t1->addr] = t1;
 667         if (t2->loc == LOC_REG)
 668                 regs[t2->addr] = t2;
 669 }
 670
 671 static int reg_get(int mask)
 672 {
 673         int i;
 674         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 675                 if ((1 << tmpregs[i]) & mask && !regs[tmpregs[i]])
 676                         return tmpregs[i];
 677         for (i = 0; i < ARRAY_SIZE(tmpregs); i++)
 678                 if ((1 << tmpregs[i]) & mask) {
 679                         reg_free(tmpregs[i]);
 680                         return tmpregs[i];
 681                 }
 682         return 0;
 683 }
 684
 685 static int reg_fortmp(struct tmp *t, int notmask)
 686 {
 687        if (t->loc == LOC_REG && !(notmask & (1 << t->addr)))
 688                return t->addr;
 689        return reg_get(~notmask);
 690 }
 691
 692 static void tmp_copy(struct tmp *t1)
 693 {
 694         struct tmp *t2 = tmp_new();
 695         memcpy(t2, t1, sizeof(*t1));
 696         if (!(t1->loc & (LOC_REG | LOC_MEM)))
 697                 return;
 698         if (t1->loc == LOC_MEM) {
 699                 tmp_mv(t2, reg_get(~0));
 700         } else if (t1->loc == LOC_REG) {
 701                 t2->addr = reg_fortmp(t2, 1 << t1->addr);
 702                 i_mov(I_MOV, t2->addr, t1->addr);
 703                 regs[t2->addr] = t2;
 704         }
 705 }
 706
 707 void o_tmpcopy(void)
 708 {
 709         tmp_copy(TMP(0));
 710 }
 711
 712 void o_cast(unsigned bt)
 713 {
 714         struct tmp *t = TMP(0);
 715         if (!t->bt && t->loc == LOC_NUM) {
 716                 num_cast(t, bt);
 717                 return;
 718         }
 719         if (BT_SZ(bt) != LONGSZ) {
 720                 int reg = reg_fortmp(t, 0);
 721                 tmp_to(t, reg);
 722                 if (bt & BT_SIGNED)
 723                         i_sx(reg, BT_SZ(bt) * 8);
 724                 else
 725                         i_zx(reg, BT_SZ(bt) * 8);
 726         }
 727 }
 728
 729 void o_func_beg(char *name, int global)
 730 {
 731         out_sym(name, (global ? OUT_GLOB : 0) | OUT_CS, cslen, 0);
 732         i_prolog();
 733         sp = 0;
 734         maxsp = sp;
 735         ntmp = 0;
 736         tmpsp = -1;
 737         nret = 0;
 738         memset(regs, 0, sizeof(regs));
 739 }
 740
 741 void o_deref(unsigned bt)
 742 {
 743         struct tmp *t = TMP(0);
 744         if (t->bt)
 745                 tmp_to(t, reg_fortmp(t, 0));
 746         t->bt = bt;
 747 }
 748
 749 void o_load(void)
 750 {
 751         struct tmp *t = TMP(0);
 752         tmp_to(t, reg_fortmp(t, 0));
 753 }
 754
 755 #define TMP_NUM(t)      ((t)->loc == LOC_NUM && !(t)->bt)
 756 #define LOCAL_PTR(t)    ((t)->loc == LOC_LOCAL && !(t)->bt)
 757 #define SYM_PTR(t)      ((t)->loc == LOC_SYM && !(t)->bt)
 758
 759 int o_popnum(long *c)
 760 {
 761         struct tmp *t = TMP(0);
 762         if (!TMP_NUM(t))
 763                 return 1;
 764         *c = t->addr;
 765         tmp_drop(1);
 766         return 0;
 767 }
 768
 769 void o_ret(int rets)
 770 {
 771         if (rets)
 772                 tmp_pop(REG_RET);
 773         else
 774                 i_num(REG_RET, 0);
 775         ret[nret++] = o_jmp(0);
 776 }
 777
 778 void o_func_end(void)
 779 {
 780         int i;
 781         for (i = 0; i < nret; i++)
 782                 o_filljmp(ret[i]);
 783         i_epilog();
 784 }
 785
 786 long o_mklocal(int size)
 787 {
 788         return sp_push(ALIGN(size, LONGSZ));
 789 }
 790
 791 void o_rmlocal(long addr, int sz)
 792 {
 793         sp = addr - sz;
 794 }
 795
 796 long o_arg2loc(int i)
 797 {
 798         return -(10 + i) << 2;
 799 }
 800
 801 void o_assign(unsigned bt)
 802 {
 803         struct tmp *t1 = TMP(0);
 804         struct tmp *t2 = TMP(1);
 805         int r1 = reg_fortmp(t1, 0);
 806         int r2 = reg_fortmp(t2, 1 << r1);
 807         int off = 0;
 808         tmp_to(t1, r1);
 809         if (t2->bt)
 810                 tmp_to(t2, r2);
 811         if (t2->loc == LOC_LOCAL) {
 812                 r2 = REG_FP;
 813                 off = t2->addr + t2->off;
 814         } else {
 815                 tmp_to(t2, r2);
 816         }
 817         tmp_drop(2);
 818         i_ldr(0, r1, r2, off, bt);
 819         tmp_push(r1);
 820 }
 821
 822 static long cu(int op, long i)
 823 {
 824         switch (op & 0xff) {
 825         case O_NEG:
 826                 return -i;
 827         case O_NOT:
 828                 return ~i;
 829         case O_LNOT:
 830                 return !i;
 831         }
 832         return 0;
 833 }
 834
 835 static int c_uop(int op)
 836 {
 837         struct tmp *t1 = TMP(0);
 838         if (!TMP_NUM(t1))
 839                 return 1;
 840         tmp_drop(1);
 841         o_num(cu(op, t1->addr));
 842         return 0;
 843 }
 844
 845 static long cb(int op, long a, long b)
 846 {
 847         switch (op & 0xff) {
 848         case O_ADD:
 849                 return a + b;
 850         case O_SUB:
 851                 return a - b;
 852         case O_AND:
 853                 return a & b;
 854         case O_OR:
 855                 return a | b;
 856         case O_XOR:
 857                 return a ^ b;
 858         case O_MUL:
 859                 return a * b;
 860         case O_DIV:
 861                 return a / b;
 862         case O_MOD:
 863                 return a % b;
 864         case O_SHL:
 865                 return a << b;
 866         case O_SHR:
 867                 if (op & O_SIGNED)
 868                         return a >> b;
 869                 else
 870                         return (unsigned long) a >> b;
 871         case O_LT:
 872                 return a < b;
 873         case O_GT:
 874                 return a > b;
 875         case O_LE:
 876                 return a <= b;
 877         case O_GE:
 878                 return a >= b;
 879         case O_EQ:
 880                 return a == b;
 881         case O_NEQ:
 882                 return a != b;
 883         }
 884         return 0;
 885 }
 886
 887 static int c_bop(int op)
 888 {
 889         struct tmp *t1 = TMP(0);
 890         struct tmp *t2 = TMP(1);
 891         int locals = LOCAL_PTR(t1) + LOCAL_PTR(t2);
 892         int syms = SYM_PTR(t1) + SYM_PTR(t2);
 893         int nums = TMP_NUM(t1) + TMP_NUM(t2);
 894         if (syms + locals == 2 || syms + nums + locals != 2)
 895                 return 1;
 896         if (nums == 1)
 897                 if ((op & 0xff) != O_ADD && ((op & 0xff) != O_SUB || TMP_NUM(t2)))
 898                         return 1;
 899         if (nums == 1) {
 900                 long o1 = TMP_NUM(t1) ? t1->addr : t1->off;
 901                 long o2 = TMP_NUM(t2) ? t2->addr : t2->off;
 902                 long ret = cb(op, o2, o1);
 903                 if (!TMP_NUM(t1))
 904                         o_tmpswap();
 905                 t2->off = ret;
 906                 tmp_drop(1);
 907         } else {
 908                 long ret = cb(op, t2->addr, t1->addr);
 909                 tmp_drop(2);
 910                 o_num(ret);
 911         }
 912         return 0;
 913 }
 914
 915 void o_uop(int op)
 916 {
 917         int r1 = reg_fortmp(TMP(0), 0);
 918         if (!c_uop(op))
 919                 return;
 920         tmp_to(TMP(0), r1);
 921         switch (op & 0xff) {
 922         case O_NEG:
 923                 i_neg(r1);
 924                 break;
 925         case O_NOT:
 926                 i_not(r1);
 927                 break;
 928         case O_LNOT:
 929                 i_lnot(r1);
 930                 break;
 931         }
 932 }
 933
 934 static void bin_regs(int *r1, int *r2)
 935 {
 936         struct tmp *t2 = TMP(0);
 937         struct tmp *t1 = TMP(1);
 938         *r2 = reg_fortmp(t2, 0);
 939         tmp_to(t2, *r2);
 940         *r1 = reg_fortmp(t1, 1 << *r2);
 941         tmp_pop(*r2);
 942         tmp_pop(*r1);
 943 }
 944
 945 static void bin_add(int op)
 946 {
 947         /* opcode for O_ADD, O_SUB, O_AND, O_OR, O_XOR */
 948         static int rx[] = {I_ADD, I_SUB, I_AND, I_ORR, I_EOR};
 949         int r1, r2;
 950         bin_regs(&r1, &r2);
 951         i_add(rx[op & 0x0f], r1, r1, r2);
 952         tmp_push(r1);
 953 }
 954
 955 static void bin_shx(int op)
 956 {
 957         int sm = SM_LSL;
 958         int r1, r2;
 959         bin_regs(&r1, &r2);
 960         if ((op & 0x0f) == 1)
 961                 sm = op & O_SIGNED ? SM_ASR : SM_LSR;
 962         i_shl(sm, r1, r1, r2);
 963         tmp_push(r1);
 964 }
 965
 966 static int log2a(unsigned long n)
 967 {
 968         int i = 0;
 969         for (i = 0; i < LONGSZ * 8; i++)
 970                 if (n & (1u << i))
 971                         break;
 972         if (i == LONGSZ * 8 || !(n >> (i + 1)))
 973                 return i;
 974         return -1;
 975 }
 976
 977 /* optimized version of mul/div/mod for powers of two */
 978 static int mul_2(int op)
 979 {
 980         struct tmp *t1 = TMP(0);
 981         struct tmp *t2 = TMP(1);
 982         long n;
 983         int r2;
 984         int p;
 985         if ((op & 0xff) == O_MUL && t2->loc == LOC_NUM && !t2->bt)
 986                 o_tmpswap();
 987         if (t1->loc != LOC_NUM || t1->bt)
 988                 return 1;
 989         n = t1->addr;
 990         p = log2a(n);
 991         if (n && p == -1)
 992                 return 1;
 993         if ((op & 0xff) == O_MUL) {
 994                 tmp_drop(1);
 995                 if (n == 1)
 996                         return 0;
 997                 if (n == 0) {
 998                         tmp_drop(1);
 999                         o_num(0);
1000                         return 0;
1001                 }
1002                 r2 = reg_fortmp(t2, 0);
1003                 tmp_to(t2, r2);
1004                 i_shl_imm(SM_LSL, r2, p);
1005                 return 0;
1006         }
1007         if (op == O_DIV) {
1008                 tmp_drop(1);
1009                 if (n == 1)
1010                         return 0;
1011                 r2 = reg_fortmp(t2, 0);
1012                 tmp_to(t2, r2);
1013                 i_shl_imm(op & O_SIGNED ? SM_ASR : SM_LSR, r2, p);
1014                 return 0;
1015         }
1016         if (op == O_MOD) {
1017                 tmp_drop(1);
1018                 if (n == 1) {
1019                         tmp_drop(1);
1020                         o_num(0);
1021                         return 0;
1022                 }
1023                 r2 = reg_fortmp(t2, 0);
1024                 tmp_to(t2, r2);
1025                 i_zx(r2, p);
1026                 return 0;
1027         }
1028         return 1;
1029 }
1030
1031 static void bin_div(int op)
1032 {
1033         struct tmp *t2 = TMP(0);
1034         struct tmp *t1 = TMP(1);
1035         char *func;
1036         int i;
1037         putdiv = 1;
1038         if ((op & 0xff) == O_DIV)
1039                 func = op & O_SIGNED ? "__divdi3" : "__udivdi3";
1040         else
1041                 func = op & O_SIGNED ? "__moddi3" : "__umoddi3";
1042         for (i = 0; i < ARRAY_SIZE(argregs); i++)
1043                 if (regs[argregs[i]] && regs[argregs[i]] - tmps < ntmp - 2)
1044                         tmp_mem(regs[argregs[i]]);
1045         tmp_to(t1, argregs[0]);
1046         tmp_to(t2, argregs[1]);
1047         tmp_drop(2);
1048         i_call(func);
1049         tmp_push(REG_RET);
1050 }
1051
1052 static void bin_mul(int op)
1053 {
1054         int r1, r2;
1055         if (!mul_2(op))
1056                 return;
1057         if ((op & 0xff) == O_DIV || (op & 0xff) == O_MOD) {
1058                 bin_div(op);
1059         } else {
1060                 bin_regs(&r1, &r2);
1061                 i_mul(r1, r1, r2);
1062                 tmp_push(r1);
1063         }
1064 }
1065
1066 static void bin_cmp(int op)
1067 {
1068         /* lt, gt, le, ge, eq, neq */
1069         static int ucond[] = {3, 8, 9, 2, 0, 1};
1070         static int scond[] = {11, 12, 13, 10, 0, 1};
1071         int r1, r2;
1072         bin_regs(&r1, &r2);
1073         i_cmp(I_CMP, r1, r2);
1074         i_set(op & O_SIGNED ? scond[op & 0x0f] : ucond[op & 0x0f], r1);
1075         tmp_push(r1);
1076 }
1077
1078 void o_bop(int op)
1079 {
1080         if (!c_bop(op))
1081                 return;
1082         if ((op & 0xf0) == 0x00)
1083                 bin_add(op);
1084         if ((op & 0xf0) == 0x10)
1085                 bin_shx(op);
1086         if ((op & 0xf0) == 0x20)
1087                 bin_mul(op);
1088         if ((op & 0xf0) == 0x30)
1089                 bin_cmp(op);
1090 }
1091
1092 static void load_regs2(int *r0, int *r1, int *r2)
1093 {
1094         struct tmp *t0 = TMP(0);
1095         struct tmp *t1 = TMP(1);
1096         struct tmp *t2 = TMP(2);
1097         *r0 = reg_fortmp(t0, 0);
1098         *r1 = reg_fortmp(t1, 1 << *r0);
1099         *r2 = reg_fortmp(t2, (1 << *r0) | (1 << *r1));
1100         tmp_to(t0, *r0);
1101         tmp_to(t1, *r1);
1102         tmp_to(t2, *r2);
1103 }
1104
1105 void o_memcpy(void)
1106 {
1107         int rd, rs, rn;
1108         load_regs2(&rn, &rs, &rd);
1109         i_memcpy(rd, rs, rn);
1110         tmp_drop(2);
1111 }
1112
1113 void o_memset(void)
1114 {
1115         int rd, rs, rn;
1116         load_regs2(&rn, &rs, &rd);
1117         i_memset(rd, rs, rn);
1118         tmp_drop(2);
1119 }
1120
1121 long o_mklabel(void)
1122 {
1123         return cslen;
1124 }
1125
1126 static long jxz(long addr, int z)
1127 {
1128         int r = reg_fortmp(TMP(0), 0);
1129         tmp_pop(r);
1130         i_b_if(addr, r, z);
1131         return cslen - 4;
1132 }
1133
1134 long o_jz(long addr)
1135 {
1136         return jxz(addr, 1);
1137 }
1138
1139 long o_jnz(long addr)
1140 {
1141         return jxz(addr, 0);
1142 }
1143
1144 long o_jmp(long addr)
1145 {
1146         i_b(addr);
1147         return cslen - 4;
1148 }
1149
1150 void o_filljmp2(long addr, long jmpdst)
1151 {
1152         i_b_fill((void *) cs + addr, jmpdst - addr);
1153 }
1154
1155 void o_filljmp(long addr)
1156 {
1157         o_filljmp2(addr, cslen);
1158 }
1159
1160 void o_call(int argc, int rets)
1161 {
1162         struct tmp *t;
1163         int i;
1164         int aregs = MIN(ARRAY_SIZE(argregs), argc);
1165         for (i = 0; i < ARRAY_SIZE(argregs); i++)
1166                 if (regs[argregs[i]] && regs[argregs[i]] - tmps < ntmp - argc)
1167                         tmp_mem(regs[argregs[i]]);
1168         if (argc > aregs) {
1169                 sp_push(LONGSZ * (argc - aregs));
1170                 for (i = argc - 1; i >= aregs; --i) {
1171                         int reg = reg_fortmp(TMP(0), 0);
1172                         tmp_pop(reg);
1173                         i_ldr(0, reg, REG_SP, (i - aregs) * LONGSZ, LONGSZ);
1174                 }
1175         }
1176         for (i = aregs - 1; i >= 0; --i)
1177                 tmp_to(TMP(aregs - i - 1), argregs[i]);
1178         tmp_drop(aregs);
1179         t = TMP(0);
1180         if (t->loc == LOC_SYM && !t->bt) {
1181                 i_call(t->sym);
1182                 tmp_drop(1);
1183         } else {
1184                 int reg = t->loc == LOC_REG ? t->addr : REG_TMP;
1185                 tmp_pop(reg);
1186                 i_call_reg(reg);
1187         }
1188         if (rets)
1189                 tmp_push(REG_RET);
1190 }
1191
1192 void o_nogen(void)
1193 {
1194         nogen++;
1195 }
1196
1197 void o_dogen(void)
1198 {
1199         nogen--;
1200 }
1201
1202 void o_mkbss(char *name, int size, int global)
1203 {
1204         out_sym(name, OUT_BSS | (global ? OUT_GLOB : 0), bsslen, size);
1205         bsslen += ALIGN(size, LONGSZ);
1206 }
1207
1208 #define MAXDATS         (1 << 10)
1209 static char dat_names[MAXDATS][NAMELEN];
1210 static int dat_offs[MAXDATS];
1211 static int ndats;
1212
1213 void err(char *msg);
1214 void *o_mkdat(char *name, int size, int global)
1215 {
1216         void *addr = ds + dslen;
1217         int idx = ndats++;
1218         if (idx >= MAXDATS)
1219                 err("nomem: MAXDATS reached!\n");
1220         strcpy(dat_names[idx], name);
1221         dat_offs[idx] = dslen;
1222         out_sym(name, OUT_DS | (global ? OUT_GLOB : 0), dslen, size);
1223         dslen += ALIGN(size, LONGSZ);
1224         return addr;
1225 }
1226
1227 static int dat_off(char *name)
1228 {
1229         int i;
1230         for (i = 0; i < ndats; i++)
1231                 if (!strcmp(name, dat_names[i]))
1232                         return dat_offs[i];
1233         return 0;
1234 }
1235
1236 void o_datset(char *name, int off, unsigned bt)
1237 {
1238         struct tmp *t = TMP(0);
1239         int sym_off = dat_off(name) + off;
1240         if (t->loc == LOC_NUM && !t->bt) {
1241                 num_cast(t, bt);
1242                 memcpy(ds + sym_off, &t->addr, BT_SZ(bt));
1243         }
1244         if (t->loc == LOC_SYM && !t->bt) {
1245                 out_rel(t->sym, OUT_DS, sym_off);
1246                 memcpy(ds + sym_off, &t->off, BT_SZ(bt));
1247         }
1248         tmp_drop(1);
1249 }
1250
1251 /* compiled division functions; div.s contains the source */
1252 static int udivdi3[] = {
1253         0xe3a02000, 0xe3a03000, 0xe1110001, 0x0a00000a,
1254         0xe1b0c211, 0xe2822001, 0x5afffffc, 0xe3a0c001,
1255         0xe2522001, 0x4a000004, 0xe1500211, 0x3afffffb,
1256         0xe0400211, 0xe083321c, 0xeafffff8, 0xe1a01000,
1257         0xe1a00003, 0xe1a0f00e,
1258 };
1259 static int umoddi3[] = {
1260         0xe92d4000, 0xebffffeb, 0xe1a00001, 0xe8bd8000,
1261 };
1262 static int divdi3[] = {
1263         0xe92d4030, 0xe1a04000, 0xe1a05001, 0xe1100000,
1264         0x42600000, 0xe1110001, 0x42611000, 0xebffffe1,
1265         0xe1340005, 0x42600000, 0xe1140004, 0x42611000,
1266         0xe8bd8030,
1267 };
1268 static int moddi3[] = {
1269         0xe92d4000, 0xebfffff0, 0xe1a00001, 0xe8bd8000,
1270 };
1271
1272 void o_write(int fd)
1273 {
1274         if (putdiv) {
1275                 out_sym("__udivdi3", OUT_CS, cslen, 0);
1276                 os(udivdi3, sizeof(udivdi3));
1277                 out_sym("__umoddi3", OUT_CS, cslen, 0);
1278                 os(umoddi3, sizeof(umoddi3));
1279                 out_sym("__divdi3", OUT_CS, cslen, 0);
1280                 os(divdi3, sizeof(divdi3));
1281                 out_sym("__moddi3", OUT_CS, cslen, 0);
1282                 os(moddi3, sizeof(moddi3));
1283         }
1284         out_write(fd, cs, cslen, ds, dslen);
1285 }