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| 1 /* |
| 2 ** $Id: lcode.c,v 2.62 2012/08/16 17:34:28 roberto Exp $ |
| 3 ** Code generator for Lua |
| 4 ** See Copyright Notice in lua.h |
| 5 */ |
| 6 |
| 7 |
| 8 #include <stdlib.h> |
| 9 |
| 10 #define lcode_c |
| 11 #define LUA_CORE |
| 12 |
| 13 #include "lua.h" |
| 14 |
| 15 #include "lcode.h" |
| 16 #include "ldebug.h" |
| 17 #include "ldo.h" |
| 18 #include "lgc.h" |
| 19 #include "llex.h" |
| 20 #include "lmem.h" |
| 21 #include "lobject.h" |
| 22 #include "lopcodes.h" |
| 23 #include "lparser.h" |
| 24 #include "lstring.h" |
| 25 #include "ltable.h" |
| 26 #include "lvm.h" |
| 27 |
| 28 |
| 29 #define hasjumps(e) ((e)->t != (e)->f) |
| 30 |
| 31 |
| 32 static int isnumeral(expdesc *e) { |
| 33 return (e->k == VKNUM && e->t == NO_JUMP && e->f == NO_JUMP); |
| 34 } |
| 35 |
| 36 |
| 37 void luaK_nil (FuncState *fs, int from, int n) { |
| 38 Instruction *previous; |
| 39 int l = from + n - 1; /* last register to set nil */ |
| 40 if (fs->pc > fs->lasttarget) { /* no jumps to current position? */ |
| 41 previous = &fs->f->code[fs->pc-1]; |
| 42 if (GET_OPCODE(*previous) == OP_LOADNIL) { |
| 43 int pfrom = GETARG_A(*previous); |
| 44 int pl = pfrom + GETARG_B(*previous); |
| 45 if ((pfrom <= from && from <= pl + 1) || |
| 46 (from <= pfrom && pfrom <= l + 1)) { /* can connect both? */ |
| 47 if (pfrom < from) from = pfrom; /* from = min(from, pfrom) */ |
| 48 if (pl > l) l = pl; /* l = max(l, pl) */ |
| 49 SETARG_A(*previous, from); |
| 50 SETARG_B(*previous, l - from); |
| 51 return; |
| 52 } |
| 53 } /* else go through */ |
| 54 } |
| 55 luaK_codeABC(fs, OP_LOADNIL, from, n - 1, 0); /* else no optimization */ |
| 56 } |
| 57 |
| 58 |
| 59 int luaK_jump (FuncState *fs) { |
| 60 int jpc = fs->jpc; /* save list of jumps to here */ |
| 61 int j; |
| 62 fs->jpc = NO_JUMP; |
| 63 j = luaK_codeAsBx(fs, OP_JMP, 0, NO_JUMP); |
| 64 luaK_concat(fs, &j, jpc); /* keep them on hold */ |
| 65 return j; |
| 66 } |
| 67 |
| 68 |
| 69 void luaK_ret (FuncState *fs, int first, int nret) { |
| 70 luaK_codeABC(fs, OP_RETURN, first, nret+1, 0); |
| 71 } |
| 72 |
| 73 |
| 74 static int condjump (FuncState *fs, OpCode op, int A, int B, int C) { |
| 75 luaK_codeABC(fs, op, A, B, C); |
| 76 return luaK_jump(fs); |
| 77 } |
| 78 |
| 79 |
| 80 static void fixjump (FuncState *fs, int pc, int dest) { |
| 81 Instruction *jmp = &fs->f->code[pc]; |
| 82 int offset = dest-(pc+1); |
| 83 lua_assert(dest != NO_JUMP); |
| 84 if (abs(offset) > MAXARG_sBx) |
| 85 luaX_syntaxerror(fs->ls, "control structure too long"); |
| 86 SETARG_sBx(*jmp, offset); |
| 87 } |
| 88 |
| 89 |
| 90 /* |
| 91 ** returns current `pc' and marks it as a jump target (to avoid wrong |
| 92 ** optimizations with consecutive instructions not in the same basic block). |
| 93 */ |
| 94 int luaK_getlabel (FuncState *fs) { |
| 95 fs->lasttarget = fs->pc; |
| 96 return fs->pc; |
| 97 } |
| 98 |
| 99 |
| 100 static int getjump (FuncState *fs, int pc) { |
| 101 int offset = GETARG_sBx(fs->f->code[pc]); |
| 102 if (offset == NO_JUMP) /* point to itself represents end of list */ |
| 103 return NO_JUMP; /* end of list */ |
| 104 else |
| 105 return (pc+1)+offset; /* turn offset into absolute position */ |
| 106 } |
| 107 |
| 108 |
| 109 static Instruction *getjumpcontrol (FuncState *fs, int pc) { |
| 110 Instruction *pi = &fs->f->code[pc]; |
| 111 if (pc >= 1 && testTMode(GET_OPCODE(*(pi-1)))) |
| 112 return pi-1; |
| 113 else |
| 114 return pi; |
| 115 } |
| 116 |
| 117 |
| 118 /* |
| 119 ** check whether list has any jump that do not produce a value |
| 120 ** (or produce an inverted value) |
| 121 */ |
| 122 static int need_value (FuncState *fs, int list) { |
| 123 for (; list != NO_JUMP; list = getjump(fs, list)) { |
| 124 Instruction i = *getjumpcontrol(fs, list); |
| 125 if (GET_OPCODE(i) != OP_TESTSET) return 1; |
| 126 } |
| 127 return 0; /* not found */ |
| 128 } |
| 129 |
| 130 |
| 131 static int patchtestreg (FuncState *fs, int node, int reg) { |
| 132 Instruction *i = getjumpcontrol(fs, node); |
| 133 if (GET_OPCODE(*i) != OP_TESTSET) |
| 134 return 0; /* cannot patch other instructions */ |
| 135 if (reg != NO_REG && reg != GETARG_B(*i)) |
| 136 SETARG_A(*i, reg); |
| 137 else /* no register to put value or register already has the value */ |
| 138 *i = CREATE_ABC(OP_TEST, GETARG_B(*i), 0, GETARG_C(*i)); |
| 139 |
| 140 return 1; |
| 141 } |
| 142 |
| 143 |
| 144 static void removevalues (FuncState *fs, int list) { |
| 145 for (; list != NO_JUMP; list = getjump(fs, list)) |
| 146 patchtestreg(fs, list, NO_REG); |
| 147 } |
| 148 |
| 149 |
| 150 static void patchlistaux (FuncState *fs, int list, int vtarget, int reg, |
| 151 int dtarget) { |
| 152 while (list != NO_JUMP) { |
| 153 int next = getjump(fs, list); |
| 154 if (patchtestreg(fs, list, reg)) |
| 155 fixjump(fs, list, vtarget); |
| 156 else |
| 157 fixjump(fs, list, dtarget); /* jump to default target */ |
| 158 list = next; |
| 159 } |
| 160 } |
| 161 |
| 162 |
| 163 static void dischargejpc (FuncState *fs) { |
| 164 patchlistaux(fs, fs->jpc, fs->pc, NO_REG, fs->pc); |
| 165 fs->jpc = NO_JUMP; |
| 166 } |
| 167 |
| 168 |
| 169 void luaK_patchlist (FuncState *fs, int list, int target) { |
| 170 if (target == fs->pc) |
| 171 luaK_patchtohere(fs, list); |
| 172 else { |
| 173 lua_assert(target < fs->pc); |
| 174 patchlistaux(fs, list, target, NO_REG, target); |
| 175 } |
| 176 } |
| 177 |
| 178 |
| 179 LUAI_FUNC void luaK_patchclose (FuncState *fs, int list, int level) { |
| 180 level++; /* argument is +1 to reserve 0 as non-op */ |
| 181 while (list != NO_JUMP) { |
| 182 int next = getjump(fs, list); |
| 183 lua_assert(GET_OPCODE(fs->f->code[list]) == OP_JMP && |
| 184 (GETARG_A(fs->f->code[list]) == 0 || |
| 185 GETARG_A(fs->f->code[list]) >= level)); |
| 186 SETARG_A(fs->f->code[list], level); |
| 187 list = next; |
| 188 } |
| 189 } |
| 190 |
| 191 |
| 192 void luaK_patchtohere (FuncState *fs, int list) { |
| 193 luaK_getlabel(fs); |
| 194 luaK_concat(fs, &fs->jpc, list); |
| 195 } |
| 196 |
| 197 |
| 198 void luaK_concat (FuncState *fs, int *l1, int l2) { |
| 199 if (l2 == NO_JUMP) return; |
| 200 else if (*l1 == NO_JUMP) |
| 201 *l1 = l2; |
| 202 else { |
| 203 int list = *l1; |
| 204 int next; |
| 205 while ((next = getjump(fs, list)) != NO_JUMP) /* find last element */ |
| 206 list = next; |
| 207 fixjump(fs, list, l2); |
| 208 } |
| 209 } |
| 210 |
| 211 |
| 212 static int luaK_code (FuncState *fs, Instruction i) { |
| 213 Proto *f = fs->f; |
| 214 dischargejpc(fs); /* `pc' will change */ |
| 215 /* put new instruction in code array */ |
| 216 luaM_growvector(fs->ls->L, f->code, fs->pc, f->sizecode, Instruction, |
| 217 MAX_INT, "opcodes"); |
| 218 f->code[fs->pc] = i; |
| 219 /* save corresponding line information */ |
| 220 luaM_growvector(fs->ls->L, f->lineinfo, fs->pc, f->sizelineinfo, int, |
| 221 MAX_INT, "opcodes"); |
| 222 f->lineinfo[fs->pc] = fs->ls->lastline; |
| 223 return fs->pc++; |
| 224 } |
| 225 |
| 226 |
| 227 int luaK_codeABC (FuncState *fs, OpCode o, int a, int b, int c) { |
| 228 lua_assert(getOpMode(o) == iABC); |
| 229 lua_assert(getBMode(o) != OpArgN || b == 0); |
| 230 lua_assert(getCMode(o) != OpArgN || c == 0); |
| 231 lua_assert(a <= MAXARG_A && b <= MAXARG_B && c <= MAXARG_C); |
| 232 return luaK_code(fs, CREATE_ABC(o, a, b, c)); |
| 233 } |
| 234 |
| 235 |
| 236 int luaK_codeABx (FuncState *fs, OpCode o, int a, unsigned int bc) { |
| 237 lua_assert(getOpMode(o) == iABx || getOpMode(o) == iAsBx); |
| 238 lua_assert(getCMode(o) == OpArgN); |
| 239 lua_assert(a <= MAXARG_A && bc <= MAXARG_Bx); |
| 240 return luaK_code(fs, CREATE_ABx(o, a, bc)); |
| 241 } |
| 242 |
| 243 |
| 244 static int codeextraarg (FuncState *fs, int a) { |
| 245 lua_assert(a <= MAXARG_Ax); |
| 246 return luaK_code(fs, CREATE_Ax(OP_EXTRAARG, a)); |
| 247 } |
| 248 |
| 249 |
| 250 int luaK_codek (FuncState *fs, int reg, int k) { |
| 251 if (k <= MAXARG_Bx) |
| 252 return luaK_codeABx(fs, OP_LOADK, reg, k); |
| 253 else { |
| 254 int p = luaK_codeABx(fs, OP_LOADKX, reg, 0); |
| 255 codeextraarg(fs, k); |
| 256 return p; |
| 257 } |
| 258 } |
| 259 |
| 260 |
| 261 void luaK_checkstack (FuncState *fs, int n) { |
| 262 int newstack = fs->freereg + n; |
| 263 if (newstack > fs->f->maxstacksize) { |
| 264 if (newstack >= MAXSTACK) |
| 265 luaX_syntaxerror(fs->ls, "function or expression too complex"); |
| 266 fs->f->maxstacksize = cast_byte(newstack); |
| 267 } |
| 268 } |
| 269 |
| 270 |
| 271 void luaK_reserveregs (FuncState *fs, int n) { |
| 272 luaK_checkstack(fs, n); |
| 273 fs->freereg += n; |
| 274 } |
| 275 |
| 276 |
| 277 static void freereg (FuncState *fs, int reg) { |
| 278 if (!ISK(reg) && reg >= fs->nactvar) { |
| 279 fs->freereg--; |
| 280 lua_assert(reg == fs->freereg); |
| 281 } |
| 282 } |
| 283 |
| 284 |
| 285 static void freeexp (FuncState *fs, expdesc *e) { |
| 286 if (e->k == VNONRELOC) |
| 287 freereg(fs, e->u.info); |
| 288 } |
| 289 |
| 290 |
| 291 static int addk (FuncState *fs, TValue *key, TValue *v) { |
| 292 lua_State *L = fs->ls->L; |
| 293 TValue *idx = luaH_set(L, fs->h, key); |
| 294 Proto *f = fs->f; |
| 295 int k, oldsize; |
| 296 if (ttisnumber(idx)) { |
| 297 lua_Number n = nvalue(idx); |
| 298 lua_number2int(k, n); |
| 299 if (luaV_rawequalobj(&f->k[k], v)) |
| 300 return k; |
| 301 /* else may be a collision (e.g., between 0.0 and "\0\0\0\0\0\0\0\0"); |
| 302 go through and create a new entry for this value */ |
| 303 } |
| 304 /* constant not found; create a new entry */ |
| 305 oldsize = f->sizek; |
| 306 k = fs->nk; |
| 307 /* numerical value does not need GC barrier; |
| 308 table has no metatable, so it does not need to invalidate cache */ |
| 309 setnvalue(idx, cast_num(k)); |
| 310 luaM_growvector(L, f->k, k, f->sizek, TValue, MAXARG_Ax, "constants"); |
| 311 while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]); |
| 312 setobj(L, &f->k[k], v); |
| 313 fs->nk++; |
| 314 luaC_barrier(L, f, v); |
| 315 return k; |
| 316 } |
| 317 |
| 318 |
| 319 int luaK_stringK (FuncState *fs, TString *s) { |
| 320 TValue o; |
| 321 setsvalue(fs->ls->L, &o, s); |
| 322 return addk(fs, &o, &o); |
| 323 } |
| 324 |
| 325 |
| 326 int luaK_numberK (FuncState *fs, lua_Number r) { |
| 327 int n; |
| 328 lua_State *L = fs->ls->L; |
| 329 TValue o; |
| 330 setnvalue(&o, r); |
| 331 if (r == 0 || luai_numisnan(NULL, r)) { /* handle -0 and NaN */ |
| 332 /* use raw representation as key to avoid numeric problems */ |
| 333 setsvalue(L, L->top++, luaS_newlstr(L, (char *)&r, sizeof(r))); |
| 334 n = addk(fs, L->top - 1, &o); |
| 335 L->top--; |
| 336 } |
| 337 else |
| 338 n = addk(fs, &o, &o); /* regular case */ |
| 339 return n; |
| 340 } |
| 341 |
| 342 |
| 343 static int boolK (FuncState *fs, int b) { |
| 344 TValue o; |
| 345 setbvalue(&o, b); |
| 346 return addk(fs, &o, &o); |
| 347 } |
| 348 |
| 349 |
| 350 static int nilK (FuncState *fs) { |
| 351 TValue k, v; |
| 352 setnilvalue(&v); |
| 353 /* cannot use nil as key; instead use table itself to represent nil */ |
| 354 sethvalue(fs->ls->L, &k, fs->h); |
| 355 return addk(fs, &k, &v); |
| 356 } |
| 357 |
| 358 |
| 359 void luaK_setreturns (FuncState *fs, expdesc *e, int nresults) { |
| 360 if (e->k == VCALL) { /* expression is an open function call? */ |
| 361 SETARG_C(getcode(fs, e), nresults+1); |
| 362 } |
| 363 else if (e->k == VVARARG) { |
| 364 SETARG_B(getcode(fs, e), nresults+1); |
| 365 SETARG_A(getcode(fs, e), fs->freereg); |
| 366 luaK_reserveregs(fs, 1); |
| 367 } |
| 368 } |
| 369 |
| 370 |
| 371 void luaK_setoneret (FuncState *fs, expdesc *e) { |
| 372 if (e->k == VCALL) { /* expression is an open function call? */ |
| 373 e->k = VNONRELOC; |
| 374 e->u.info = GETARG_A(getcode(fs, e)); |
| 375 } |
| 376 else if (e->k == VVARARG) { |
| 377 SETARG_B(getcode(fs, e), 2); |
| 378 e->k = VRELOCABLE; /* can relocate its simple result */ |
| 379 } |
| 380 } |
| 381 |
| 382 |
| 383 void luaK_dischargevars (FuncState *fs, expdesc *e) { |
| 384 switch (e->k) { |
| 385 case VLOCAL: { |
| 386 e->k = VNONRELOC; |
| 387 break; |
| 388 } |
| 389 case VUPVAL: { |
| 390 e->u.info = luaK_codeABC(fs, OP_GETUPVAL, 0, e->u.info, 0); |
| 391 e->k = VRELOCABLE; |
| 392 break; |
| 393 } |
| 394 case VINDEXED: { |
| 395 OpCode op = OP_GETTABUP; /* assume 't' is in an upvalue */ |
| 396 freereg(fs, e->u.ind.idx); |
| 397 if (e->u.ind.vt == VLOCAL) { /* 't' is in a register? */ |
| 398 freereg(fs, e->u.ind.t); |
| 399 op = OP_GETTABLE; |
| 400 } |
| 401 e->u.info = luaK_codeABC(fs, op, 0, e->u.ind.t, e->u.ind.idx); |
| 402 e->k = VRELOCABLE; |
| 403 break; |
| 404 } |
| 405 case VVARARG: |
| 406 case VCALL: { |
| 407 luaK_setoneret(fs, e); |
| 408 break; |
| 409 } |
| 410 default: break; /* there is one value available (somewhere) */ |
| 411 } |
| 412 } |
| 413 |
| 414 |
| 415 static int code_label (FuncState *fs, int A, int b, int jump) { |
| 416 luaK_getlabel(fs); /* those instructions may be jump targets */ |
| 417 return luaK_codeABC(fs, OP_LOADBOOL, A, b, jump); |
| 418 } |
| 419 |
| 420 |
| 421 static void discharge2reg (FuncState *fs, expdesc *e, int reg) { |
| 422 luaK_dischargevars(fs, e); |
| 423 switch (e->k) { |
| 424 case VNIL: { |
| 425 luaK_nil(fs, reg, 1); |
| 426 break; |
| 427 } |
| 428 case VFALSE: case VTRUE: { |
| 429 luaK_codeABC(fs, OP_LOADBOOL, reg, e->k == VTRUE, 0); |
| 430 break; |
| 431 } |
| 432 case VK: { |
| 433 luaK_codek(fs, reg, e->u.info); |
| 434 break; |
| 435 } |
| 436 case VKNUM: { |
| 437 luaK_codek(fs, reg, luaK_numberK(fs, e->u.nval)); |
| 438 break; |
| 439 } |
| 440 case VRELOCABLE: { |
| 441 Instruction *pc = &getcode(fs, e); |
| 442 SETARG_A(*pc, reg); |
| 443 break; |
| 444 } |
| 445 case VNONRELOC: { |
| 446 if (reg != e->u.info) |
| 447 luaK_codeABC(fs, OP_MOVE, reg, e->u.info, 0); |
| 448 break; |
| 449 } |
| 450 default: { |
| 451 lua_assert(e->k == VVOID || e->k == VJMP); |
| 452 return; /* nothing to do... */ |
| 453 } |
| 454 } |
| 455 e->u.info = reg; |
| 456 e->k = VNONRELOC; |
| 457 } |
| 458 |
| 459 |
| 460 static void discharge2anyreg (FuncState *fs, expdesc *e) { |
| 461 if (e->k != VNONRELOC) { |
| 462 luaK_reserveregs(fs, 1); |
| 463 discharge2reg(fs, e, fs->freereg-1); |
| 464 } |
| 465 } |
| 466 |
| 467 |
| 468 static void exp2reg (FuncState *fs, expdesc *e, int reg) { |
| 469 discharge2reg(fs, e, reg); |
| 470 if (e->k == VJMP) |
| 471 luaK_concat(fs, &e->t, e->u.info); /* put this jump in `t' list */ |
| 472 if (hasjumps(e)) { |
| 473 int final; /* position after whole expression */ |
| 474 int p_f = NO_JUMP; /* position of an eventual LOAD false */ |
| 475 int p_t = NO_JUMP; /* position of an eventual LOAD true */ |
| 476 if (need_value(fs, e->t) || need_value(fs, e->f)) { |
| 477 int fj = (e->k == VJMP) ? NO_JUMP : luaK_jump(fs); |
| 478 p_f = code_label(fs, reg, 0, 1); |
| 479 p_t = code_label(fs, reg, 1, 0); |
| 480 luaK_patchtohere(fs, fj); |
| 481 } |
| 482 final = luaK_getlabel(fs); |
| 483 patchlistaux(fs, e->f, final, reg, p_f); |
| 484 patchlistaux(fs, e->t, final, reg, p_t); |
| 485 } |
| 486 e->f = e->t = NO_JUMP; |
| 487 e->u.info = reg; |
| 488 e->k = VNONRELOC; |
| 489 } |
| 490 |
| 491 |
| 492 void luaK_exp2nextreg (FuncState *fs, expdesc *e) { |
| 493 luaK_dischargevars(fs, e); |
| 494 freeexp(fs, e); |
| 495 luaK_reserveregs(fs, 1); |
| 496 exp2reg(fs, e, fs->freereg - 1); |
| 497 } |
| 498 |
| 499 |
| 500 int luaK_exp2anyreg (FuncState *fs, expdesc *e) { |
| 501 luaK_dischargevars(fs, e); |
| 502 if (e->k == VNONRELOC) { |
| 503 if (!hasjumps(e)) return e->u.info; /* exp is already in a register */ |
| 504 if (e->u.info >= fs->nactvar) { /* reg. is not a local? */ |
| 505 exp2reg(fs, e, e->u.info); /* put value on it */ |
| 506 return e->u.info; |
| 507 } |
| 508 } |
| 509 luaK_exp2nextreg(fs, e); /* default */ |
| 510 return e->u.info; |
| 511 } |
| 512 |
| 513 |
| 514 void luaK_exp2anyregup (FuncState *fs, expdesc *e) { |
| 515 if (e->k != VUPVAL || hasjumps(e)) |
| 516 luaK_exp2anyreg(fs, e); |
| 517 } |
| 518 |
| 519 |
| 520 void luaK_exp2val (FuncState *fs, expdesc *e) { |
| 521 if (hasjumps(e)) |
| 522 luaK_exp2anyreg(fs, e); |
| 523 else |
| 524 luaK_dischargevars(fs, e); |
| 525 } |
| 526 |
| 527 |
| 528 int luaK_exp2RK (FuncState *fs, expdesc *e) { |
| 529 luaK_exp2val(fs, e); |
| 530 switch (e->k) { |
| 531 case VTRUE: |
| 532 case VFALSE: |
| 533 case VNIL: { |
| 534 if (fs->nk <= MAXINDEXRK) { /* constant fits in RK operand? */ |
| 535 e->u.info = (e->k == VNIL) ? nilK(fs) : boolK(fs, (e->k == VTRUE)); |
| 536 e->k = VK; |
| 537 return RKASK(e->u.info); |
| 538 } |
| 539 else break; |
| 540 } |
| 541 case VKNUM: { |
| 542 e->u.info = luaK_numberK(fs, e->u.nval); |
| 543 e->k = VK; |
| 544 /* go through */ |
| 545 } |
| 546 case VK: { |
| 547 if (e->u.info <= MAXINDEXRK) /* constant fits in argC? */ |
| 548 return RKASK(e->u.info); |
| 549 else break; |
| 550 } |
| 551 default: break; |
| 552 } |
| 553 /* not a constant in the right range: put it in a register */ |
| 554 return luaK_exp2anyreg(fs, e); |
| 555 } |
| 556 |
| 557 |
| 558 void luaK_storevar (FuncState *fs, expdesc *var, expdesc *ex) { |
| 559 switch (var->k) { |
| 560 case VLOCAL: { |
| 561 freeexp(fs, ex); |
| 562 exp2reg(fs, ex, var->u.info); |
| 563 return; |
| 564 } |
| 565 case VUPVAL: { |
| 566 int e = luaK_exp2anyreg(fs, ex); |
| 567 luaK_codeABC(fs, OP_SETUPVAL, e, var->u.info, 0); |
| 568 break; |
| 569 } |
| 570 case VINDEXED: { |
| 571 OpCode op = (var->u.ind.vt == VLOCAL) ? OP_SETTABLE : OP_SETTABUP; |
| 572 int e = luaK_exp2RK(fs, ex); |
| 573 luaK_codeABC(fs, op, var->u.ind.t, var->u.ind.idx, e); |
| 574 break; |
| 575 } |
| 576 default: { |
| 577 lua_assert(0); /* invalid var kind to store */ |
| 578 break; |
| 579 } |
| 580 } |
| 581 freeexp(fs, ex); |
| 582 } |
| 583 |
| 584 |
| 585 void luaK_self (FuncState *fs, expdesc *e, expdesc *key) { |
| 586 int ereg; |
| 587 luaK_exp2anyreg(fs, e); |
| 588 ereg = e->u.info; /* register where 'e' was placed */ |
| 589 freeexp(fs, e); |
| 590 e->u.info = fs->freereg; /* base register for op_self */ |
| 591 e->k = VNONRELOC; |
| 592 luaK_reserveregs(fs, 2); /* function and 'self' produced by op_self */ |
| 593 luaK_codeABC(fs, OP_SELF, e->u.info, ereg, luaK_exp2RK(fs, key)); |
| 594 freeexp(fs, key); |
| 595 } |
| 596 |
| 597 |
| 598 static void invertjump (FuncState *fs, expdesc *e) { |
| 599 Instruction *pc = getjumpcontrol(fs, e->u.info); |
| 600 lua_assert(testTMode(GET_OPCODE(*pc)) && GET_OPCODE(*pc) != OP_TESTSET && |
| 601 GET_OPCODE(*pc) != OP_TEST); |
| 602 SETARG_A(*pc, !(GETARG_A(*pc))); |
| 603 } |
| 604 |
| 605 |
| 606 static int jumponcond (FuncState *fs, expdesc *e, int cond) { |
| 607 if (e->k == VRELOCABLE) { |
| 608 Instruction ie = getcode(fs, e); |
| 609 if (GET_OPCODE(ie) == OP_NOT) { |
| 610 fs->pc--; /* remove previous OP_NOT */ |
| 611 return condjump(fs, OP_TEST, GETARG_B(ie), 0, !cond); |
| 612 } |
| 613 /* else go through */ |
| 614 } |
| 615 discharge2anyreg(fs, e); |
| 616 freeexp(fs, e); |
| 617 return condjump(fs, OP_TESTSET, NO_REG, e->u.info, cond); |
| 618 } |
| 619 |
| 620 |
| 621 void luaK_goiftrue (FuncState *fs, expdesc *e) { |
| 622 int pc; /* pc of last jump */ |
| 623 luaK_dischargevars(fs, e); |
| 624 switch (e->k) { |
| 625 case VJMP: { |
| 626 invertjump(fs, e); |
| 627 pc = e->u.info; |
| 628 break; |
| 629 } |
| 630 case VK: case VKNUM: case VTRUE: { |
| 631 pc = NO_JUMP; /* always true; do nothing */ |
| 632 break; |
| 633 } |
| 634 default: { |
| 635 pc = jumponcond(fs, e, 0); |
| 636 break; |
| 637 } |
| 638 } |
| 639 luaK_concat(fs, &e->f, pc); /* insert last jump in `f' list */ |
| 640 luaK_patchtohere(fs, e->t); |
| 641 e->t = NO_JUMP; |
| 642 } |
| 643 |
| 644 |
| 645 void luaK_goiffalse (FuncState *fs, expdesc *e) { |
| 646 int pc; /* pc of last jump */ |
| 647 luaK_dischargevars(fs, e); |
| 648 switch (e->k) { |
| 649 case VJMP: { |
| 650 pc = e->u.info; |
| 651 break; |
| 652 } |
| 653 case VNIL: case VFALSE: { |
| 654 pc = NO_JUMP; /* always false; do nothing */ |
| 655 break; |
| 656 } |
| 657 default: { |
| 658 pc = jumponcond(fs, e, 1); |
| 659 break; |
| 660 } |
| 661 } |
| 662 luaK_concat(fs, &e->t, pc); /* insert last jump in `t' list */ |
| 663 luaK_patchtohere(fs, e->f); |
| 664 e->f = NO_JUMP; |
| 665 } |
| 666 |
| 667 |
| 668 static void codenot (FuncState *fs, expdesc *e) { |
| 669 luaK_dischargevars(fs, e); |
| 670 switch (e->k) { |
| 671 case VNIL: case VFALSE: { |
| 672 e->k = VTRUE; |
| 673 break; |
| 674 } |
| 675 case VK: case VKNUM: case VTRUE: { |
| 676 e->k = VFALSE; |
| 677 break; |
| 678 } |
| 679 case VJMP: { |
| 680 invertjump(fs, e); |
| 681 break; |
| 682 } |
| 683 case VRELOCABLE: |
| 684 case VNONRELOC: { |
| 685 discharge2anyreg(fs, e); |
| 686 freeexp(fs, e); |
| 687 e->u.info = luaK_codeABC(fs, OP_NOT, 0, e->u.info, 0); |
| 688 e->k = VRELOCABLE; |
| 689 break; |
| 690 } |
| 691 default: { |
| 692 lua_assert(0); /* cannot happen */ |
| 693 break; |
| 694 } |
| 695 } |
| 696 /* interchange true and false lists */ |
| 697 { int temp = e->f; e->f = e->t; e->t = temp; } |
| 698 removevalues(fs, e->f); |
| 699 removevalues(fs, e->t); |
| 700 } |
| 701 |
| 702 |
| 703 void luaK_indexed (FuncState *fs, expdesc *t, expdesc *k) { |
| 704 lua_assert(!hasjumps(t)); |
| 705 t->u.ind.t = t->u.info; |
| 706 t->u.ind.idx = luaK_exp2RK(fs, k); |
| 707 t->u.ind.vt = (t->k == VUPVAL) ? VUPVAL |
| 708 : check_exp(vkisinreg(t->k), VLOCAL); |
| 709 t->k = VINDEXED; |
| 710 } |
| 711 |
| 712 |
| 713 static int constfolding (OpCode op, expdesc *e1, expdesc *e2) { |
| 714 lua_Number r; |
| 715 if (!isnumeral(e1) || !isnumeral(e2)) return 0; |
| 716 if ((op == OP_DIV || op == OP_MOD) && e2->u.nval == 0) |
| 717 return 0; /* do not attempt to divide by 0 */ |
| 718 r = luaO_arith(op - OP_ADD + LUA_OPADD, e1->u.nval, e2->u.nval); |
| 719 e1->u.nval = r; |
| 720 return 1; |
| 721 } |
| 722 |
| 723 |
| 724 static void codearith (FuncState *fs, OpCode op, |
| 725 expdesc *e1, expdesc *e2, int line) { |
| 726 if (constfolding(op, e1, e2)) |
| 727 return; |
| 728 else { |
| 729 int o2 = (op != OP_UNM && op != OP_LEN) ? luaK_exp2RK(fs, e2) : 0; |
| 730 int o1 = luaK_exp2RK(fs, e1); |
| 731 if (o1 > o2) { |
| 732 freeexp(fs, e1); |
| 733 freeexp(fs, e2); |
| 734 } |
| 735 else { |
| 736 freeexp(fs, e2); |
| 737 freeexp(fs, e1); |
| 738 } |
| 739 e1->u.info = luaK_codeABC(fs, op, 0, o1, o2); |
| 740 e1->k = VRELOCABLE; |
| 741 luaK_fixline(fs, line); |
| 742 } |
| 743 } |
| 744 |
| 745 |
| 746 static void codecomp (FuncState *fs, OpCode op, int cond, expdesc *e1, |
| 747 expdesc *e2) { |
| 748 int o1 = luaK_exp2RK(fs, e1); |
| 749 int o2 = luaK_exp2RK(fs, e2); |
| 750 freeexp(fs, e2); |
| 751 freeexp(fs, e1); |
| 752 if (cond == 0 && op != OP_EQ) { |
| 753 int temp; /* exchange args to replace by `<' or `<=' */ |
| 754 temp = o1; o1 = o2; o2 = temp; /* o1 <==> o2 */ |
| 755 cond = 1; |
| 756 } |
| 757 e1->u.info = condjump(fs, op, cond, o1, o2); |
| 758 e1->k = VJMP; |
| 759 } |
| 760 |
| 761 |
| 762 void luaK_prefix (FuncState *fs, UnOpr op, expdesc *e, int line) { |
| 763 expdesc e2; |
| 764 e2.t = e2.f = NO_JUMP; e2.k = VKNUM; e2.u.nval = 0; |
| 765 switch (op) { |
| 766 case OPR_MINUS: { |
| 767 if (isnumeral(e)) /* minus constant? */ |
| 768 e->u.nval = luai_numunm(NULL, e->u.nval); /* fold it */ |
| 769 else { |
| 770 luaK_exp2anyreg(fs, e); |
| 771 codearith(fs, OP_UNM, e, &e2, line); |
| 772 } |
| 773 break; |
| 774 } |
| 775 case OPR_NOT: codenot(fs, e); break; |
| 776 case OPR_LEN: { |
| 777 luaK_exp2anyreg(fs, e); /* cannot operate on constants */ |
| 778 codearith(fs, OP_LEN, e, &e2, line); |
| 779 break; |
| 780 } |
| 781 default: lua_assert(0); |
| 782 } |
| 783 } |
| 784 |
| 785 |
| 786 void luaK_infix (FuncState *fs, BinOpr op, expdesc *v) { |
| 787 switch (op) { |
| 788 case OPR_AND: { |
| 789 luaK_goiftrue(fs, v); |
| 790 break; |
| 791 } |
| 792 case OPR_OR: { |
| 793 luaK_goiffalse(fs, v); |
| 794 break; |
| 795 } |
| 796 case OPR_CONCAT: { |
| 797 luaK_exp2nextreg(fs, v); /* operand must be on the `stack' */ |
| 798 break; |
| 799 } |
| 800 case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV: |
| 801 case OPR_MOD: case OPR_POW: { |
| 802 if (!isnumeral(v)) luaK_exp2RK(fs, v); |
| 803 break; |
| 804 } |
| 805 default: { |
| 806 luaK_exp2RK(fs, v); |
| 807 break; |
| 808 } |
| 809 } |
| 810 } |
| 811 |
| 812 |
| 813 void luaK_posfix (FuncState *fs, BinOpr op, |
| 814 expdesc *e1, expdesc *e2, int line) { |
| 815 switch (op) { |
| 816 case OPR_AND: { |
| 817 lua_assert(e1->t == NO_JUMP); /* list must be closed */ |
| 818 luaK_dischargevars(fs, e2); |
| 819 luaK_concat(fs, &e2->f, e1->f); |
| 820 *e1 = *e2; |
| 821 break; |
| 822 } |
| 823 case OPR_OR: { |
| 824 lua_assert(e1->f == NO_JUMP); /* list must be closed */ |
| 825 luaK_dischargevars(fs, e2); |
| 826 luaK_concat(fs, &e2->t, e1->t); |
| 827 *e1 = *e2; |
| 828 break; |
| 829 } |
| 830 case OPR_CONCAT: { |
| 831 luaK_exp2val(fs, e2); |
| 832 if (e2->k == VRELOCABLE && GET_OPCODE(getcode(fs, e2)) == OP_CONCAT) { |
| 833 lua_assert(e1->u.info == GETARG_B(getcode(fs, e2))-1); |
| 834 freeexp(fs, e1); |
| 835 SETARG_B(getcode(fs, e2), e1->u.info); |
| 836 e1->k = VRELOCABLE; e1->u.info = e2->u.info; |
| 837 } |
| 838 else { |
| 839 luaK_exp2nextreg(fs, e2); /* operand must be on the 'stack' */ |
| 840 codearith(fs, OP_CONCAT, e1, e2, line); |
| 841 } |
| 842 break; |
| 843 } |
| 844 case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV: |
| 845 case OPR_MOD: case OPR_POW: { |
| 846 codearith(fs, cast(OpCode, op - OPR_ADD + OP_ADD), e1, e2, line); |
| 847 break; |
| 848 } |
| 849 case OPR_EQ: case OPR_LT: case OPR_LE: { |
| 850 codecomp(fs, cast(OpCode, op - OPR_EQ + OP_EQ), 1, e1, e2); |
| 851 break; |
| 852 } |
| 853 case OPR_NE: case OPR_GT: case OPR_GE: { |
| 854 codecomp(fs, cast(OpCode, op - OPR_NE + OP_EQ), 0, e1, e2); |
| 855 break; |
| 856 } |
| 857 default: lua_assert(0); |
| 858 } |
| 859 } |
| 860 |
| 861 |
| 862 void luaK_fixline (FuncState *fs, int line) { |
| 863 fs->f->lineinfo[fs->pc - 1] = line; |
| 864 } |
| 865 |
| 866 |
| 867 void luaK_setlist (FuncState *fs, int base, int nelems, int tostore) { |
| 868 int c = (nelems - 1)/LFIELDS_PER_FLUSH + 1; |
| 869 int b = (tostore == LUA_MULTRET) ? 0 : tostore; |
| 870 lua_assert(tostore != 0); |
| 871 if (c <= MAXARG_C) |
| 872 luaK_codeABC(fs, OP_SETLIST, base, b, c); |
| 873 else if (c <= MAXARG_Ax) { |
| 874 luaK_codeABC(fs, OP_SETLIST, base, b, 0); |
| 875 codeextraarg(fs, c); |
| 876 } |
| 877 else |
| 878 luaX_syntaxerror(fs->ls, "constructor too long"); |
| 879 fs->freereg = base + 1; /* free registers with list values */ |
| 880 } |
| 881 |
OLD | NEW |