1/* $NetBSD$ */ 2 3/* 4** Id: lvm.c,v 2.63.1.3 2007/12/28 15:32:23 roberto Exp 5** Lua virtual machine 6** See Copyright Notice in lua.h 7*/ 8 9 10#include <stdio.h> 11#include <stdlib.h> 12#include <string.h> 13 14#define lvm_c 15#define LUA_CORE 16 17#include "lua.h" 18 19#include "ldebug.h" 20#include "ldo.h" 21#include "lfunc.h" 22#include "lgc.h" 23#include "lobject.h" 24#include "lopcodes.h" 25#include "lstate.h" 26#include "lstring.h" 27#include "ltable.h" 28#include "ltm.h" 29#include "lvm.h" 30 31 32 33/* limit for table tag-method chains (to avoid loops) */ 34#define MAXTAGLOOP 100 35 36 37const TValue *luaV_tonumber (const TValue *obj, TValue *n) { 38 lua_Number num; 39 if (ttisnumber(obj)) return obj; 40 if (ttisstring(obj) && luaO_str2d(svalue(obj), &num)) { 41 setnvalue(n, num); 42 return n; 43 } 44 else 45 return NULL; 46} 47 48 49int luaV_tostring (lua_State *L, StkId obj) { 50 if (!ttisnumber(obj)) 51 return 0; 52 else { 53 char s[LUAI_MAXNUMBER2STR]; 54 lua_Number n = nvalue(obj); 55 lua_number2str(s, n); 56 setsvalue2s(L, obj, luaS_new(L, s)); 57 return 1; 58 } 59} 60 61 62static void traceexec (lua_State *L, const Instruction *pc) { 63 lu_byte mask = L->hookmask; 64 const Instruction *oldpc = L->savedpc; 65 L->savedpc = pc; 66 if ((mask & LUA_MASKCOUNT) && L->hookcount == 0) { 67 resethookcount(L); 68 luaD_callhook(L, LUA_HOOKCOUNT, -1); 69 } 70 if (mask & LUA_MASKLINE) { 71 Proto *p = ci_func(L->ci)->l.p; 72 int npc = pcRel(pc, p); 73 int newline = getline(p, npc); 74 /* call linehook when enter a new function, when jump back (loop), 75 or when enter a new line */ 76 if (npc == 0 || pc <= oldpc || newline != getline(p, pcRel(oldpc, p))) 77 luaD_callhook(L, LUA_HOOKLINE, newline); 78 } 79} 80 81 82static void callTMres (lua_State *L, StkId res, const TValue *f, 83 const TValue *p1, const TValue *p2) { 84 ptrdiff_t result = savestack(L, res); 85 setobj2s(L, L->top, f); /* push function */ 86 setobj2s(L, L->top+1, p1); /* 1st argument */ 87 setobj2s(L, L->top+2, p2); /* 2nd argument */ 88 luaD_checkstack(L, 3); 89 L->top += 3; 90 luaD_call(L, L->top - 3, 1); 91 res = restorestack(L, result); 92 L->top--; 93 setobjs2s(L, res, L->top); 94} 95 96 97 98static void callTM (lua_State *L, const TValue *f, const TValue *p1, 99 const TValue *p2, const TValue *p3) { 100 setobj2s(L, L->top, f); /* push function */ 101 setobj2s(L, L->top+1, p1); /* 1st argument */ 102 setobj2s(L, L->top+2, p2); /* 2nd argument */ 103 setobj2s(L, L->top+3, p3); /* 3th argument */ 104 luaD_checkstack(L, 4); 105 L->top += 4; 106 luaD_call(L, L->top - 4, 0); 107} 108 109 110void luaV_gettable (lua_State *L, const TValue *t, TValue *key, StkId val) { 111 int loop; 112 for (loop = 0; loop < MAXTAGLOOP; loop++) { 113 const TValue *tm; 114 if (ttistable(t)) { /* `t' is a table? */ 115 Table *h = hvalue(t); 116 const TValue *res = luaH_get(h, key); /* do a primitive get */ 117 if (!ttisnil(res) || /* result is no nil? */ 118 (tm = fasttm(L, h->metatable, TM_INDEX)) == NULL) { /* or no TM? */ 119 setobj2s(L, val, res); 120 return; 121 } 122 /* else will try the tag method */ 123 } 124 else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_INDEX))) 125 luaG_typeerror(L, t, "index"); 126 if (ttisfunction(tm)) { 127 callTMres(L, val, tm, t, key); 128 return; 129 } 130 t = tm; /* else repeat with `tm' */ 131 } 132 luaG_runerror(L, "loop in gettable"); 133} 134 135 136void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) { 137 int loop; 138 for (loop = 0; loop < MAXTAGLOOP; loop++) { 139 const TValue *tm; 140 if (ttistable(t)) { /* `t' is a table? */ 141 Table *h = hvalue(t); 142 TValue *oldval = luaH_set(L, h, key); /* do a primitive set */ 143 if (!ttisnil(oldval) || /* result is no nil? */ 144 (tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL) { /* or no TM? */ 145 setobj2t(L, oldval, val); 146 luaC_barriert(L, h, val); 147 return; 148 } 149 /* else will try the tag method */ 150 } 151 else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX))) 152 luaG_typeerror(L, t, "index"); 153 if (ttisfunction(tm)) { 154 callTM(L, tm, t, key, val); 155 return; 156 } 157 t = tm; /* else repeat with `tm' */ 158 } 159 luaG_runerror(L, "loop in settable"); 160} 161 162 163static int call_binTM (lua_State *L, const TValue *p1, const TValue *p2, 164 StkId res, TMS event) { 165 const TValue *tm = luaT_gettmbyobj(L, p1, event); /* try first operand */ 166 if (ttisnil(tm)) 167 tm = luaT_gettmbyobj(L, p2, event); /* try second operand */ 168 if (ttisnil(tm)) return 0; 169 callTMres(L, res, tm, p1, p2); 170 return 1; 171} 172 173 174static const TValue *get_compTM (lua_State *L, Table *mt1, Table *mt2, 175 TMS event) { 176 const TValue *tm1 = fasttm(L, mt1, event); 177 const TValue *tm2; 178 if (tm1 == NULL) return NULL; /* no metamethod */ 179 if (mt1 == mt2) return tm1; /* same metatables => same metamethods */ 180 tm2 = fasttm(L, mt2, event); 181 if (tm2 == NULL) return NULL; /* no metamethod */ 182 if (luaO_rawequalObj(tm1, tm2)) /* same metamethods? */ 183 return tm1; 184 return NULL; 185} 186 187 188static int call_orderTM (lua_State *L, const TValue *p1, const TValue *p2, 189 TMS event) { 190 const TValue *tm1 = luaT_gettmbyobj(L, p1, event); 191 const TValue *tm2; 192 if (ttisnil(tm1)) return -1; /* no metamethod? */ 193 tm2 = luaT_gettmbyobj(L, p2, event); 194 if (!luaO_rawequalObj(tm1, tm2)) /* different metamethods? */ 195 return -1; 196 callTMres(L, L->top, tm1, p1, p2); 197 return !l_isfalse(L->top); 198} 199 200 201static int l_strcmp (const TString *ls, const TString *rs) { 202 const char *l = getstr(ls); 203 size_t ll = ls->tsv.len; 204 const char *r = getstr(rs); 205 size_t lr = rs->tsv.len; 206 for (;;) { 207 int temp = strcoll(l, r); 208 if (temp != 0) return temp; 209 else { /* strings are equal up to a `\0' */ 210 size_t len = strlen(l); /* index of first `\0' in both strings */ 211 if (len == lr) /* r is finished? */ 212 return (len == ll) ? 0 : 1; 213 else if (len == ll) /* l is finished? */ 214 return -1; /* l is smaller than r (because r is not finished) */ 215 /* both strings longer than `len'; go on comparing (after the `\0') */ 216 len++; 217 l += len; ll -= len; r += len; lr -= len; 218 } 219 } 220} 221 222 223int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) { 224 int res; 225 if (ttype(l) != ttype(r)) 226 return luaG_ordererror(L, l, r); 227 else if (ttisnumber(l)) 228 return luai_numlt(nvalue(l), nvalue(r)); 229 else if (ttisstring(l)) 230 return l_strcmp(rawtsvalue(l), rawtsvalue(r)) < 0; 231 else if ((res = call_orderTM(L, l, r, TM_LT)) != -1) 232 return res; 233 return luaG_ordererror(L, l, r); 234} 235 236 237static int lessequal (lua_State *L, const TValue *l, const TValue *r) { 238 int res; 239 if (ttype(l) != ttype(r)) 240 return luaG_ordererror(L, l, r); 241 else if (ttisnumber(l)) 242 return luai_numle(nvalue(l), nvalue(r)); 243 else if (ttisstring(l)) 244 return l_strcmp(rawtsvalue(l), rawtsvalue(r)) <= 0; 245 else if ((res = call_orderTM(L, l, r, TM_LE)) != -1) /* first try `le' */ 246 return res; 247 else if ((res = call_orderTM(L, r, l, TM_LT)) != -1) /* else try `lt' */ 248 return !res; 249 return luaG_ordererror(L, l, r); 250} 251 252 253int luaV_equalval (lua_State *L, const TValue *t1, const TValue *t2) { 254 const TValue *tm; 255 lua_assert(ttype(t1) == ttype(t2)); 256 switch (ttype(t1)) { 257 case LUA_TNIL: return 1; 258 case LUA_TNUMBER: return luai_numeq(nvalue(t1), nvalue(t2)); 259 case LUA_TBOOLEAN: return bvalue(t1) == bvalue(t2); /* true must be 1 !! */ 260 case LUA_TLIGHTUSERDATA: return pvalue(t1) == pvalue(t2); 261 case LUA_TUSERDATA: { 262 if (uvalue(t1) == uvalue(t2)) return 1; 263 tm = get_compTM(L, uvalue(t1)->metatable, uvalue(t2)->metatable, 264 TM_EQ); 265 break; /* will try TM */ 266 } 267 case LUA_TTABLE: { 268 if (hvalue(t1) == hvalue(t2)) return 1; 269 tm = get_compTM(L, hvalue(t1)->metatable, hvalue(t2)->metatable, TM_EQ); 270 break; /* will try TM */ 271 } 272 default: return gcvalue(t1) == gcvalue(t2); 273 } 274 if (tm == NULL) return 0; /* no TM? */ 275 callTMres(L, L->top, tm, t1, t2); /* call TM */ 276 return !l_isfalse(L->top); 277} 278 279 280void luaV_concat (lua_State *L, int total, int last) { 281 do { 282 StkId top = L->base + last + 1; 283 int n = 2; /* number of elements handled in this pass (at least 2) */ 284 if (!(ttisstring(top-2) || ttisnumber(top-2)) || !tostring(L, top-1)) { 285 if (!call_binTM(L, top-2, top-1, top-2, TM_CONCAT)) 286 luaG_concaterror(L, top-2, top-1); 287 } else if (tsvalue(top-1)->len == 0) /* second op is empty? */ 288 (void)tostring(L, top - 2); /* result is first op (as string) */ 289 else { 290 /* at least two string values; get as many as possible */ 291 size_t tl = tsvalue(top-1)->len; 292 char *buffer; 293 int i; 294 /* collect total length */ 295 for (n = 1; n < total && tostring(L, top-n-1); n++) { 296 size_t l = tsvalue(top-n-1)->len; 297 if (l >= MAX_SIZET - tl) luaG_runerror(L, "string length overflow"); 298 tl += l; 299 } 300 buffer = luaZ_openspace(L, &G(L)->buff, tl); 301 tl = 0; 302 for (i=n; i>0; i--) { /* concat all strings */ 303 size_t l = tsvalue(top-i)->len; 304 memcpy(buffer+tl, svalue(top-i), l); 305 tl += l; 306 } 307 setsvalue2s(L, top-n, luaS_newlstr(L, buffer, tl)); 308 } 309 total -= n-1; /* got `n' strings to create 1 new */ 310 last -= n-1; 311 } while (total > 1); /* repeat until only 1 result left */ 312} 313 314 315static void Arith (lua_State *L, StkId ra, const TValue *rb, 316 const TValue *rc, TMS op) { 317 TValue tempb, tempc; 318 const TValue *b, *c; 319 if ((b = luaV_tonumber(rb, &tempb)) != NULL && 320 (c = luaV_tonumber(rc, &tempc)) != NULL) { 321 lua_Number nb = nvalue(b), nc = nvalue(c); 322 switch (op) { 323 case TM_ADD: setnvalue(ra, luai_numadd(nb, nc)); break; 324 case TM_SUB: setnvalue(ra, luai_numsub(nb, nc)); break; 325 case TM_MUL: setnvalue(ra, luai_nummul(nb, nc)); break; 326 case TM_DIV: setnvalue(ra, luai_numdiv(nb, nc)); break; 327 case TM_MOD: setnvalue(ra, luai_nummod(nb, nc)); break; 328 case TM_POW: setnvalue(ra, luai_numpow(nb, nc)); break; 329 case TM_UNM: setnvalue(ra, luai_numunm(nb)); break; 330 default: lua_assert(0); break; 331 } 332 } 333 else if (!call_binTM(L, rb, rc, ra, op)) 334 luaG_aritherror(L, rb, rc); 335} 336 337 338 339/* 340** some macros for common tasks in `luaV_execute' 341*/ 342 343#define runtime_check(L, c) { if (!(c)) break; } 344 345#define RA(i) (base+GETARG_A(i)) 346/* to be used after possible stack reallocation */ 347#define RB(i) check_exp(getBMode(GET_OPCODE(i)) == OpArgR, base+GETARG_B(i)) 348#define RC(i) check_exp(getCMode(GET_OPCODE(i)) == OpArgR, base+GETARG_C(i)) 349#define RKB(i) check_exp(getBMode(GET_OPCODE(i)) == OpArgK, \ 350 ISK(GETARG_B(i)) ? k+INDEXK(GETARG_B(i)) : base+GETARG_B(i)) 351#define RKC(i) check_exp(getCMode(GET_OPCODE(i)) == OpArgK, \ 352 ISK(GETARG_C(i)) ? k+INDEXK(GETARG_C(i)) : base+GETARG_C(i)) 353#define KBx(i) check_exp(getBMode(GET_OPCODE(i)) == OpArgK, k+GETARG_Bx(i)) 354 355 356#define dojump(L,pc,i) {(pc) += (i); luai_threadyield(L);} 357 358 359#define Protect(x) { L->savedpc = pc; {x;}; base = L->base; } 360 361 362#define arith_op(op,tm) { \ 363 TValue *rb = RKB(i); \ 364 TValue *rc = RKC(i); \ 365 if (ttisnumber(rb) && ttisnumber(rc)) { \ 366 lua_Number nb = nvalue(rb), nc = nvalue(rc); \ 367 setnvalue(ra, op(nb, nc)); \ 368 } \ 369 else \ 370 Protect(Arith(L, ra, rb, rc, tm)); \ 371 } 372 373 374 375void luaV_execute (lua_State *L, int nexeccalls) { 376 LClosure *cl; 377 StkId base; 378 TValue *k; 379 const Instruction *pc; 380 reentry: /* entry point */ 381 lua_assert(isLua(L->ci)); 382 pc = L->savedpc; 383 cl = &clvalue(L->ci->func)->l; 384 base = L->base; 385 k = cl->p->k; 386 /* main loop of interpreter */ 387 for (;;) { 388 const Instruction i = *pc++; 389 StkId ra; 390 if ((L->hookmask & (LUA_MASKLINE | LUA_MASKCOUNT)) && 391 (--L->hookcount == 0 || L->hookmask & LUA_MASKLINE)) { 392 traceexec(L, pc); 393 if (L->status == LUA_YIELD) { /* did hook yield? */ 394 L->savedpc = pc - 1; 395 return; 396 } 397 base = L->base; 398 } 399 /* warning!! several calls may realloc the stack and invalidate `ra' */ 400 ra = RA(i); 401 lua_assert(base == L->base && L->base == L->ci->base); 402 lua_assert(base <= L->top && L->top <= L->stack + L->stacksize); 403 lua_assert(L->top == L->ci->top || luaG_checkopenop(i)); 404 switch (GET_OPCODE(i)) { 405 case OP_MOVE: { 406 setobjs2s(L, ra, RB(i)); 407 continue; 408 } 409 case OP_LOADK: { 410 setobj2s(L, ra, KBx(i)); 411 continue; 412 } 413 case OP_LOADBOOL: { 414 setbvalue(ra, GETARG_B(i)); 415 if (GETARG_C(i)) pc++; /* skip next instruction (if C) */ 416 continue; 417 } 418 case OP_LOADNIL: { 419 TValue *rb = RB(i); 420 do { 421 setnilvalue(rb--); 422 } while (rb >= ra); 423 continue; 424 } 425 case OP_GETUPVAL: { 426 int b = GETARG_B(i); 427 setobj2s(L, ra, cl->upvals[b]->v); 428 continue; 429 } 430 case OP_GETGLOBAL: { 431 TValue g; 432 TValue *rb = KBx(i); 433 sethvalue(L, &g, cl->env); 434 lua_assert(ttisstring(rb)); 435 Protect(luaV_gettable(L, &g, rb, ra)); 436 continue; 437 } 438 case OP_GETTABLE: { 439 Protect(luaV_gettable(L, RB(i), RKC(i), ra)); 440 continue; 441 } 442 case OP_SETGLOBAL: { 443 TValue g; 444 sethvalue(L, &g, cl->env); 445 lua_assert(ttisstring(KBx(i))); 446 Protect(luaV_settable(L, &g, KBx(i), ra)); 447 continue; 448 } 449 case OP_SETUPVAL: { 450 UpVal *uv = cl->upvals[GETARG_B(i)]; 451 setobj(L, uv->v, ra); 452 luaC_barrier(L, uv, ra); 453 continue; 454 } 455 case OP_SETTABLE: { 456 Protect(luaV_settable(L, ra, RKB(i), RKC(i))); 457 continue; 458 } 459 case OP_NEWTABLE: { 460 int b = GETARG_B(i); 461 int c = GETARG_C(i); 462 sethvalue(L, ra, luaH_new(L, luaO_fb2int(b), luaO_fb2int(c))); 463 Protect(luaC_checkGC(L)); 464 continue; 465 } 466 case OP_SELF: { 467 StkId rb = RB(i); 468 setobjs2s(L, ra+1, rb); 469 Protect(luaV_gettable(L, rb, RKC(i), ra)); 470 continue; 471 } 472 case OP_ADD: { 473 arith_op(luai_numadd, TM_ADD); 474 continue; 475 } 476 case OP_SUB: { 477 arith_op(luai_numsub, TM_SUB); 478 continue; 479 } 480 case OP_MUL: { 481 arith_op(luai_nummul, TM_MUL); 482 continue; 483 } 484 case OP_DIV: { 485 arith_op(luai_numdiv, TM_DIV); 486 continue; 487 } 488 case OP_MOD: { 489 arith_op(luai_nummod, TM_MOD); 490 continue; 491 } 492 case OP_POW: { 493 arith_op(luai_numpow, TM_POW); 494 continue; 495 } 496 case OP_UNM: { 497 TValue *rb = RB(i); 498 if (ttisnumber(rb)) { 499 lua_Number nb = nvalue(rb); 500 setnvalue(ra, luai_numunm(nb)); 501 } 502 else { 503 Protect(Arith(L, ra, rb, rb, TM_UNM)); 504 } 505 continue; 506 } 507 case OP_NOT: { 508 int res = l_isfalse(RB(i)); /* next assignment may change this value */ 509 setbvalue(ra, res); 510 continue; 511 } 512 case OP_LEN: { 513 const TValue *rb = RB(i); 514 switch (ttype(rb)) { 515 case LUA_TTABLE: { 516 setnvalue(ra, cast_num(luaH_getn(hvalue(rb)))); 517 break; 518 } 519 case LUA_TSTRING: { 520 setnvalue(ra, cast_num(tsvalue(rb)->len)); 521 break; 522 } 523 default: { /* try metamethod */ 524 Protect( 525 if (!call_binTM(L, rb, luaO_nilobject, ra, TM_LEN)) 526 luaG_typeerror(L, rb, "get length of"); 527 ) 528 } 529 } 530 continue; 531 } 532 case OP_CONCAT: { 533 int b = GETARG_B(i); 534 int c = GETARG_C(i); 535 Protect(luaV_concat(L, c-b+1, c); luaC_checkGC(L)); 536 setobjs2s(L, RA(i), base+b); 537 continue; 538 } 539 case OP_JMP: { 540 dojump(L, pc, GETARG_sBx(i)); 541 continue; 542 } 543 case OP_EQ: { 544 TValue *rb = RKB(i); 545 TValue *rc = RKC(i); 546 Protect( 547 if (equalobj(L, rb, rc) == GETARG_A(i)) 548 dojump(L, pc, GETARG_sBx(*pc)); 549 ) 550 pc++; 551 continue; 552 } 553 case OP_LT: { 554 Protect( 555 if (luaV_lessthan(L, RKB(i), RKC(i)) == GETARG_A(i)) 556 dojump(L, pc, GETARG_sBx(*pc)); 557 ) 558 pc++; 559 continue; 560 } 561 case OP_LE: { 562 Protect( 563 if (lessequal(L, RKB(i), RKC(i)) == GETARG_A(i)) 564 dojump(L, pc, GETARG_sBx(*pc)); 565 ) 566 pc++; 567 continue; 568 } 569 case OP_TEST: { 570 if (l_isfalse(ra) != GETARG_C(i)) 571 dojump(L, pc, GETARG_sBx(*pc)); 572 pc++; 573 continue; 574 } 575 case OP_TESTSET: { 576 TValue *rb = RB(i); 577 if (l_isfalse(rb) != GETARG_C(i)) { 578 setobjs2s(L, ra, rb); 579 dojump(L, pc, GETARG_sBx(*pc)); 580 } 581 pc++; 582 continue; 583 } 584 case OP_CALL: { 585 int b = GETARG_B(i); 586 int nresults = GETARG_C(i) - 1; 587 if (b != 0) L->top = ra+b; /* else previous instruction set top */ 588 L->savedpc = pc; 589 switch (luaD_precall(L, ra, nresults)) { 590 case PCRLUA: { 591 nexeccalls++; 592 goto reentry; /* restart luaV_execute over new Lua function */ 593 } 594 case PCRC: { 595 /* it was a C function (`precall' called it); adjust results */ 596 if (nresults >= 0) L->top = L->ci->top; 597 base = L->base; 598 continue; 599 } 600 default: { 601 return; /* yield */ 602 } 603 } 604 } 605 case OP_TAILCALL: { 606 int b = GETARG_B(i); 607 if (b != 0) L->top = ra+b; /* else previous instruction set top */ 608 L->savedpc = pc; 609 lua_assert(GETARG_C(i) - 1 == LUA_MULTRET); 610 switch (luaD_precall(L, ra, LUA_MULTRET)) { 611 case PCRLUA: { 612 /* tail call: put new frame in place of previous one */ 613 CallInfo *ci = L->ci - 1; /* previous frame */ 614 int aux; 615 StkId func = ci->func; 616 StkId pfunc = (ci+1)->func; /* previous function index */ 617 if (L->openupval) luaF_close(L, ci->base); 618 L->base = ci->base = ci->func + ((ci+1)->base - pfunc); 619 for (aux = 0; pfunc+aux < L->top; aux++) /* move frame down */ 620 setobjs2s(L, func+aux, pfunc+aux); 621 ci->top = L->top = func+aux; /* correct top */ 622 lua_assert(L->top == L->base + clvalue(func)->l.p->maxstacksize); 623 ci->savedpc = L->savedpc; 624 ci->tailcalls++; /* one more call lost */ 625 L->ci--; /* remove new frame */ 626 goto reentry; 627 } 628 case PCRC: { /* it was a C function (`precall' called it) */ 629 base = L->base; 630 continue; 631 } 632 default: { 633 return; /* yield */ 634 } 635 } 636 } 637 case OP_RETURN: { 638 int b = GETARG_B(i); 639 if (b != 0) L->top = ra+b-1; 640 if (L->openupval) luaF_close(L, base); 641 L->savedpc = pc; 642 b = luaD_poscall(L, ra); 643 if (--nexeccalls == 0) /* was previous function running `here'? */ 644 return; /* no: return */ 645 else { /* yes: continue its execution */ 646 if (b) L->top = L->ci->top; 647 lua_assert(isLua(L->ci)); 648 lua_assert(GET_OPCODE(*((L->ci)->savedpc - 1)) == OP_CALL); 649 goto reentry; 650 } 651 } 652 case OP_FORLOOP: { 653 lua_Number step = nvalue(ra+2); 654 lua_Number idx = luai_numadd(nvalue(ra), step); /* increment index */ 655 lua_Number limit = nvalue(ra+1); 656 if (luai_numlt(0, step) ? luai_numle(idx, limit) 657 : luai_numle(limit, idx)) { 658 dojump(L, pc, GETARG_sBx(i)); /* jump back */ 659 setnvalue(ra, idx); /* update internal index... */ 660 setnvalue(ra+3, idx); /* ...and external index */ 661 } 662 continue; 663 } 664 case OP_FORPREP: { 665 const TValue *init = ra; 666 const TValue *plimit = ra+1; 667 const TValue *pstep = ra+2; 668 L->savedpc = pc; /* next steps may throw errors */ 669 if (!tonumber(init, ra)) 670 luaG_runerror(L, LUA_QL("for") " initial value must be a number"); 671 else if (!tonumber(plimit, ra+1)) 672 luaG_runerror(L, LUA_QL("for") " limit must be a number"); 673 else if (!tonumber(pstep, ra+2)) 674 luaG_runerror(L, LUA_QL("for") " step must be a number"); 675 setnvalue(ra, luai_numsub(nvalue(ra), nvalue(pstep))); 676 dojump(L, pc, GETARG_sBx(i)); 677 continue; 678 } 679 case OP_TFORLOOP: { 680 StkId cb = ra + 3; /* call base */ 681 setobjs2s(L, cb+2, ra+2); 682 setobjs2s(L, cb+1, ra+1); 683 setobjs2s(L, cb, ra); 684 L->top = cb+3; /* func. + 2 args (state and index) */ 685 Protect(luaD_call(L, cb, GETARG_C(i))); 686 L->top = L->ci->top; 687 cb = RA(i) + 3; /* previous call may change the stack */ 688 if (!ttisnil(cb)) { /* continue loop? */ 689 setobjs2s(L, cb-1, cb); /* save control variable */ 690 dojump(L, pc, GETARG_sBx(*pc)); /* jump back */ 691 } 692 pc++; 693 continue; 694 } 695 case OP_SETLIST: { 696 int n = GETARG_B(i); 697 int c = GETARG_C(i); 698 int last; 699 Table *h; 700 if (n == 0) { 701 n = cast_int(L->top - ra) - 1; 702 L->top = L->ci->top; 703 } 704 if (c == 0) c = cast_int(*pc++); 705 runtime_check(L, ttistable(ra)); 706 h = hvalue(ra); 707 last = ((c-1)*LFIELDS_PER_FLUSH) + n; 708 if (last > h->sizearray) /* needs more space? */ 709 luaH_resizearray(L, h, last); /* pre-alloc it at once */ 710 for (; n > 0; n--) { 711 TValue *val = ra+n; 712 setobj2t(L, luaH_setnum(L, h, last--), val); 713 luaC_barriert(L, h, val); 714 } 715 continue; 716 } 717 case OP_CLOSE: { 718 luaF_close(L, ra); 719 continue; 720 } 721 case OP_CLOSURE: { 722 Proto *p; 723 Closure *ncl; 724 int nup, j; 725 p = cl->p->p[GETARG_Bx(i)]; 726 nup = p->nups; 727 ncl = luaF_newLclosure(L, nup, cl->env); 728 ncl->l.p = p; 729 for (j=0; j<nup; j++, pc++) { 730 if (GET_OPCODE(*pc) == OP_GETUPVAL) 731 ncl->l.upvals[j] = cl->upvals[GETARG_B(*pc)]; 732 else { 733 lua_assert(GET_OPCODE(*pc) == OP_MOVE); 734 ncl->l.upvals[j] = luaF_findupval(L, base + GETARG_B(*pc)); 735 } 736 } 737 setclvalue(L, ra, ncl); 738 Protect(luaC_checkGC(L)); 739 continue; 740 } 741 case OP_VARARG: { 742 int b = GETARG_B(i) - 1; 743 int j; 744 CallInfo *ci = L->ci; 745 int n = cast_int(ci->base - ci->func) - cl->p->numparams - 1; 746 if (b == LUA_MULTRET) { 747 Protect(luaD_checkstack(L, n)); 748 ra = RA(i); /* previous call may change the stack */ 749 b = n; 750 L->top = ra + n; 751 } 752 for (j = 0; j < b; j++) { 753 if (j < n) { 754 setobjs2s(L, ra + j, ci->base - n + j); 755 } 756 else { 757 setnilvalue(ra + j); 758 } 759 } 760 continue; 761 } 762 } 763 } 764} 765 766