1 /* 2 ** $Id: lvm.c $ 3 ** Lua virtual machine 4 ** See Copyright Notice in lua.h 5 */ 6 7 #define lvm_c 8 #define LUA_CORE 9 10 #include "lprefix.h" 11 12 #include <float.h> 13 #include <limits.h> 14 #include <math.h> 15 #include <stdio.h> 16 #include <stdlib.h> 17 #include <string.h> 18 19 #include "lua.h" 20 21 #include "ldebug.h" 22 #include "ldo.h" 23 #include "lfunc.h" 24 #include "lgc.h" 25 #include "lobject.h" 26 #include "lopcodes.h" 27 #include "lstate.h" 28 #include "lstring.h" 29 #include "ltable.h" 30 #include "ltm.h" 31 #include "lvm.h" 32 33 34 /* 35 ** By default, use jump tables in the main interpreter loop on gcc 36 ** and compatible compilers. 37 */ 38 #if !defined(LUA_USE_JUMPTABLE) 39 #if defined(__GNUC__) 40 #define LUA_USE_JUMPTABLE 1 41 #else 42 #define LUA_USE_JUMPTABLE 0 43 #endif 44 #endif 45 46 47 48 /* limit for table tag-method chains (to avoid infinite loops) */ 49 #define MAXTAGLOOP 2000 50 51 52 /* 53 ** 'l_intfitsf' checks whether a given integer is in the range that 54 ** can be converted to a float without rounding. Used in comparisons. 55 */ 56 #if !defined(l_intfitsf) && LUA_FLOAT_TYPE != LUA_FLOAT_INT64 57 58 /* number of bits in the mantissa of a float */ 59 #define NBM (l_floatatt(MANT_DIG)) 60 61 /* 62 ** Check whether some integers may not fit in a float, testing whether 63 ** (maxinteger >> NBM) > 0. (That implies (1 << NBM) <= maxinteger.) 64 ** (The shifts are done in parts, to avoid shifting by more than the size 65 ** of an integer. In a worst case, NBM == 113 for long double and 66 ** sizeof(long) == 32.) 67 */ 68 #if ((((LUA_MAXINTEGER >> (NBM / 4)) >> (NBM / 4)) >> (NBM / 4)) \ 69 >> (NBM - (3 * (NBM / 4)))) > 0 70 71 /* limit for integers that fit in a float */ 72 #define MAXINTFITSF ((lua_Unsigned)1 << NBM) 73 74 /* check whether 'i' is in the interval [-MAXINTFITSF, MAXINTFITSF] */ 75 #define l_intfitsf(i) ((MAXINTFITSF + l_castS2U(i)) <= (2 * MAXINTFITSF)) 76 77 #else /* all integers fit in a float precisely */ 78 79 #define l_intfitsf(i) 1 80 81 #endif 82 83 #endif /* !defined(l_intfitsf) && LUA_FLOAT_TYPE != LUA_FLOAT_INT64 */ 84 85 #ifndef l_intfitsf 86 #define l_intfitsf(i) 1 87 #endif 88 89 90 /* 91 ** Try to convert a value from string to a number value. 92 ** If the value is not a string or is a string not representing 93 ** a valid numeral (or if coercions from strings to numbers 94 ** are disabled via macro 'cvt2num'), do not modify 'result' 95 ** and return 0. 96 */ 97 static int l_strton (const TValue *obj, TValue *result) { 98 lua_assert(obj != result); 99 if (!cvt2num(obj)) /* is object not a string? */ 100 return 0; 101 else 102 return (luaO_str2num(svalue(obj), result) == vslen(obj) + 1); 103 } 104 105 106 /* 107 ** Try to convert a value to a float. The float case is already handled 108 ** by the macro 'tonumber'. 109 */ 110 int luaV_tonumber_ (const TValue *obj, lua_Number *n) { 111 TValue v; 112 if (ttisinteger(obj)) { 113 *n = cast_num(ivalue(obj)); 114 return 1; 115 } 116 else if (l_strton(obj, &v)) { /* string coercible to number? */ 117 *n = nvalue(&v); /* convert result of 'luaO_str2num' to a float */ 118 return 1; 119 } 120 else 121 return 0; /* conversion failed */ 122 } 123 124 125 /* 126 ** try to convert a float to an integer, rounding according to 'mode'. 127 */ 128 int luaV_flttointeger (lua_Number n, lua_Integer *p, F2Imod mode) { 129 lua_Number f = l_floor(n); 130 if (n != f) { /* not an integral value? */ 131 if (mode == F2Ieq) return 0; /* fails if mode demands integral value */ 132 else if (mode == F2Iceil) /* needs ceil? */ 133 f += 1; /* convert floor to ceil (remember: n != f) */ 134 } 135 return lua_numbertointeger(f, p); 136 } 137 138 139 /* 140 ** try to convert a value to an integer, rounding according to 'mode', 141 ** without string coercion. 142 ** ("Fast track" handled by macro 'tointegerns'.) 143 */ 144 int luaV_tointegerns (const TValue *obj, lua_Integer *p, F2Imod mode) { 145 if (ttisfloat(obj)) 146 return luaV_flttointeger(fltvalue(obj), p, mode); 147 else if (ttisinteger(obj)) { 148 *p = ivalue(obj); 149 return 1; 150 } 151 else 152 return 0; 153 } 154 155 156 /* 157 ** try to convert a value to an integer. 158 */ 159 int luaV_tointeger (const TValue *obj, lua_Integer *p, F2Imod mode) { 160 TValue v; 161 if (l_strton(obj, &v)) /* does 'obj' point to a numerical string? */ 162 obj = &v; /* change it to point to its corresponding number */ 163 return luaV_tointegerns(obj, p, mode); 164 } 165 166 167 /* 168 ** Try to convert a 'for' limit to an integer, preserving the semantics 169 ** of the loop. Return true if the loop must not run; otherwise, '*p' 170 ** gets the integer limit. 171 ** (The following explanation assumes a positive step; it is valid for 172 ** negative steps mutatis mutandis.) 173 ** If the limit is an integer or can be converted to an integer, 174 ** rounding down, that is the limit. 175 ** Otherwise, check whether the limit can be converted to a float. If 176 ** the float is too large, clip it to LUA_MAXINTEGER. If the float 177 ** is too negative, the loop should not run, because any initial 178 ** integer value is greater than such limit; so, the function returns 179 ** true to signal that. (For this latter case, no integer limit would be 180 ** correct; even a limit of LUA_MININTEGER would run the loop once for 181 ** an initial value equal to LUA_MININTEGER.) 182 */ 183 static int forlimit (lua_State *L, lua_Integer init, const TValue *lim, 184 lua_Integer *p, lua_Integer step) { 185 if (!luaV_tointeger(lim, p, (step < 0 ? F2Iceil : F2Ifloor))) { 186 /* not coercible to in integer */ 187 lua_Number flim; /* try to convert to float */ 188 if (!tonumber(lim, &flim)) /* cannot convert to float? */ 189 luaG_forerror(L, lim, "limit"); 190 /* else 'flim' is a float out of integer bounds */ 191 if (luai_numlt(0, flim)) { /* if it is positive, it is too large */ 192 if (step < 0) return 1; /* initial value must be less than it */ 193 *p = LUA_MAXINTEGER; /* truncate */ 194 } 195 else { /* it is less than min integer */ 196 if (step > 0) return 1; /* initial value must be greater than it */ 197 *p = LUA_MININTEGER; /* truncate */ 198 } 199 } 200 return (step > 0 ? init > *p : init < *p); /* not to run? */ 201 } 202 203 204 /* 205 ** Prepare a numerical for loop (opcode OP_FORPREP). 206 ** Return true to skip the loop. Otherwise, 207 ** after preparation, stack will be as follows: 208 ** ra : internal index (safe copy of the control variable) 209 ** ra + 1 : loop counter (integer loops) or limit (float loops) 210 ** ra + 2 : step 211 ** ra + 3 : control variable 212 */ 213 static int forprep (lua_State *L, StkId ra) { 214 TValue *pinit = s2v(ra); 215 TValue *plimit = s2v(ra + 1); 216 TValue *pstep = s2v(ra + 2); 217 if (ttisinteger(pinit) && ttisinteger(pstep)) { /* integer loop? */ 218 lua_Integer init = ivalue(pinit); 219 lua_Integer step = ivalue(pstep); 220 lua_Integer limit; 221 if (step == 0) 222 luaG_runerror(L, "'for' step is zero"); 223 setivalue(s2v(ra + 3), init); /* control variable */ 224 if (forlimit(L, init, plimit, &limit, step)) 225 return 1; /* skip the loop */ 226 else { /* prepare loop counter */ 227 lua_Unsigned count; 228 if (step > 0) { /* ascending loop? */ 229 count = l_castS2U(limit) - l_castS2U(init); 230 if (step != 1) /* avoid division in the too common case */ 231 count /= l_castS2U(step); 232 } 233 else { /* step < 0; descending loop */ 234 count = l_castS2U(init) - l_castS2U(limit); 235 /* 'step+1' avoids negating 'mininteger' */ 236 count /= l_castS2U(-(step + 1)) + 1u; 237 } 238 /* store the counter in place of the limit (which won't be 239 needed anymore) */ 240 setivalue(plimit, l_castU2S(count)); 241 } 242 } 243 else { /* try making all values floats */ 244 lua_Number init; lua_Number limit; lua_Number step; 245 if (unlikely(!tonumber(plimit, &limit))) 246 luaG_forerror(L, plimit, "limit"); 247 if (unlikely(!tonumber(pstep, &step))) 248 luaG_forerror(L, pstep, "step"); 249 if (unlikely(!tonumber(pinit, &init))) 250 luaG_forerror(L, pinit, "initial value"); 251 if (step == 0) 252 luaG_runerror(L, "'for' step is zero"); 253 if (luai_numlt(0, step) ? luai_numlt(limit, init) 254 : luai_numlt(init, limit)) 255 return 1; /* skip the loop */ 256 else { 257 /* make sure internal values are all floats */ 258 setfltvalue(plimit, limit); 259 setfltvalue(pstep, step); 260 setfltvalue(s2v(ra), init); /* internal index */ 261 setfltvalue(s2v(ra + 3), init); /* control variable */ 262 } 263 } 264 return 0; 265 } 266 267 268 /* 269 ** Execute a step of a float numerical for loop, returning 270 ** true iff the loop must continue. (The integer case is 271 ** written online with opcode OP_FORLOOP, for performance.) 272 */ 273 static int floatforloop (StkId ra) { 274 lua_Number step = fltvalue(s2v(ra + 2)); 275 lua_Number limit = fltvalue(s2v(ra + 1)); 276 lua_Number idx = fltvalue(s2v(ra)); /* internal index */ 277 idx = luai_numadd(L, idx, step); /* increment index */ 278 if (luai_numlt(0, step) ? luai_numle(idx, limit) 279 : luai_numle(limit, idx)) { 280 chgfltvalue(s2v(ra), idx); /* update internal index */ 281 setfltvalue(s2v(ra + 3), idx); /* and control variable */ 282 return 1; /* jump back */ 283 } 284 else 285 return 0; /* finish the loop */ 286 } 287 288 289 /* 290 ** Finish the table access 'val = t[key]'. 291 ** if 'slot' is NULL, 't' is not a table; otherwise, 'slot' points to 292 ** t[k] entry (which must be empty). 293 */ 294 void luaV_finishget (lua_State *L, const TValue *t, TValue *key, StkId val, 295 const TValue *slot) { 296 int loop; /* counter to avoid infinite loops */ 297 const TValue *tm; /* metamethod */ 298 for (loop = 0; loop < MAXTAGLOOP; loop++) { 299 if (slot == NULL) { /* 't' is not a table? */ 300 lua_assert(!ttistable(t)); 301 tm = luaT_gettmbyobj(L, t, TM_INDEX); 302 if (unlikely(notm(tm))) 303 luaG_typeerror(L, t, "index"); /* no metamethod */ 304 /* else will try the metamethod */ 305 } 306 else { /* 't' is a table */ 307 lua_assert(isempty(slot)); 308 tm = fasttm(L, hvalue(t)->metatable, TM_INDEX); /* table's metamethod */ 309 if (tm == NULL) { /* no metamethod? */ 310 setnilvalue(s2v(val)); /* result is nil */ 311 return; 312 } 313 /* else will try the metamethod */ 314 } 315 if (ttisfunction(tm)) { /* is metamethod a function? */ 316 luaT_callTMres(L, tm, t, key, val); /* call it */ 317 return; 318 } 319 t = tm; /* else try to access 'tm[key]' */ 320 if (luaV_fastget(L, t, key, slot, luaH_get)) { /* fast track? */ 321 setobj2s(L, val, slot); /* done */ 322 return; 323 } 324 /* else repeat (tail call 'luaV_finishget') */ 325 } 326 luaG_runerror(L, "'__index' chain too long; possible loop"); 327 } 328 329 330 /* 331 ** Finish a table assignment 't[key] = val'. 332 ** If 'slot' is NULL, 't' is not a table. Otherwise, 'slot' points 333 ** to the entry 't[key]', or to a value with an absent key if there 334 ** is no such entry. (The value at 'slot' must be empty, otherwise 335 ** 'luaV_fastget' would have done the job.) 336 */ 337 void luaV_finishset (lua_State *L, const TValue *t, TValue *key, 338 TValue *val, const TValue *slot) { 339 int loop; /* counter to avoid infinite loops */ 340 for (loop = 0; loop < MAXTAGLOOP; loop++) { 341 const TValue *tm; /* '__newindex' metamethod */ 342 if (slot != NULL) { /* is 't' a table? */ 343 Table *h = hvalue(t); /* save 't' table */ 344 lua_assert(isempty(slot)); /* slot must be empty */ 345 tm = fasttm(L, h->metatable, TM_NEWINDEX); /* get metamethod */ 346 if (tm == NULL) { /* no metamethod? */ 347 if (isabstkey(slot)) /* no previous entry? */ 348 slot = luaH_newkey(L, h, key); /* create one */ 349 /* no metamethod and (now) there is an entry with given key */ 350 setobj2t(L, cast(TValue *, slot), val); /* set its new value */ 351 invalidateTMcache(h); 352 luaC_barrierback(L, obj2gco(h), val); 353 return; 354 } 355 /* else will try the metamethod */ 356 } 357 else { /* not a table; check metamethod */ 358 tm = luaT_gettmbyobj(L, t, TM_NEWINDEX); 359 if (unlikely(notm(tm))) 360 luaG_typeerror(L, t, "index"); 361 } 362 /* try the metamethod */ 363 if (ttisfunction(tm)) { 364 luaT_callTM(L, tm, t, key, val); 365 return; 366 } 367 t = tm; /* else repeat assignment over 'tm' */ 368 if (luaV_fastget(L, t, key, slot, luaH_get)) { 369 luaV_finishfastset(L, t, slot, val); 370 return; /* done */ 371 } 372 /* else 'return luaV_finishset(L, t, key, val, slot)' (loop) */ 373 } 374 luaG_runerror(L, "'__newindex' chain too long; possible loop"); 375 } 376 377 378 /* 379 ** Compare two strings 'ls' x 'rs', returning an integer less-equal- 380 ** -greater than zero if 'ls' is less-equal-greater than 'rs'. 381 ** The code is a little tricky because it allows '\0' in the strings 382 ** and it uses 'strcoll' (to respect locales) for each segments 383 ** of the strings. 384 */ 385 static int l_strcmp (const TString *ls, const TString *rs) { 386 const char *l = getstr(ls); 387 size_t ll = tsslen(ls); 388 const char *r = getstr(rs); 389 size_t lr = tsslen(rs); 390 for (;;) { /* for each segment */ 391 int temp = strcoll(l, r); 392 if (temp != 0) /* not equal? */ 393 return temp; /* done */ 394 else { /* strings are equal up to a '\0' */ 395 size_t len = strlen(l); /* index of first '\0' in both strings */ 396 if (len == lr) /* 'rs' is finished? */ 397 return (len == ll) ? 0 : 1; /* check 'ls' */ 398 else if (len == ll) /* 'ls' is finished? */ 399 return -1; /* 'ls' is less than 'rs' ('rs' is not finished) */ 400 /* both strings longer than 'len'; go on comparing after the '\0' */ 401 len++; 402 l += len; ll -= len; r += len; lr -= len; 403 } 404 } 405 } 406 407 408 /* 409 ** Check whether integer 'i' is less than float 'f'. If 'i' has an 410 ** exact representation as a float ('l_intfitsf'), compare numbers as 411 ** floats. Otherwise, use the equivalence 'i < f <=> i < ceil(f)'. 412 ** If 'ceil(f)' is out of integer range, either 'f' is greater than 413 ** all integers or less than all integers. 414 ** (The test with 'l_intfitsf' is only for performance; the else 415 ** case is correct for all values, but it is slow due to the conversion 416 ** from float to int.) 417 ** When 'f' is NaN, comparisons must result in false. 418 */ 419 static int LTintfloat (lua_Integer i, lua_Number f) { 420 if (l_intfitsf(i)) 421 return luai_numlt(cast_num(i), f); /* compare them as floats */ 422 else { /* i < f <=> i < ceil(f) */ 423 lua_Integer fi; 424 if (luaV_flttointeger(f, &fi, F2Iceil)) /* fi = ceil(f) */ 425 return i < fi; /* compare them as integers */ 426 else /* 'f' is either greater or less than all integers */ 427 return f > 0; /* greater? */ 428 } 429 } 430 431 432 /* 433 ** Check whether integer 'i' is less than or equal to float 'f'. 434 ** See comments on previous function. 435 */ 436 static int LEintfloat (lua_Integer i, lua_Number f) { 437 if (l_intfitsf(i)) 438 return luai_numle(cast_num(i), f); /* compare them as floats */ 439 else { /* i <= f <=> i <= floor(f) */ 440 lua_Integer fi; 441 if (luaV_flttointeger(f, &fi, F2Ifloor)) /* fi = floor(f) */ 442 return i <= fi; /* compare them as integers */ 443 else /* 'f' is either greater or less than all integers */ 444 return f > 0; /* greater? */ 445 } 446 } 447 448 449 /* 450 ** Check whether float 'f' is less than integer 'i'. 451 ** See comments on previous function. 452 */ 453 static int LTfloatint (lua_Number f, lua_Integer i) { 454 if (l_intfitsf(i)) 455 return luai_numlt(f, cast_num(i)); /* compare them as floats */ 456 else { /* f < i <=> floor(f) < i */ 457 lua_Integer fi; 458 if (luaV_flttointeger(f, &fi, F2Ifloor)) /* fi = floor(f) */ 459 return fi < i; /* compare them as integers */ 460 else /* 'f' is either greater or less than all integers */ 461 return f < 0; /* less? */ 462 } 463 } 464 465 466 /* 467 ** Check whether float 'f' is less than or equal to integer 'i'. 468 ** See comments on previous function. 469 */ 470 static int LEfloatint (lua_Number f, lua_Integer i) { 471 if (l_intfitsf(i)) 472 return luai_numle(f, cast_num(i)); /* compare them as floats */ 473 else { /* f <= i <=> ceil(f) <= i */ 474 lua_Integer fi; 475 if (luaV_flttointeger(f, &fi, F2Iceil)) /* fi = ceil(f) */ 476 return fi <= i; /* compare them as integers */ 477 else /* 'f' is either greater or less than all integers */ 478 return f < 0; /* less? */ 479 } 480 } 481 482 483 /* 484 ** Return 'l < r', for numbers. 485 */ 486 static int LTnum (const TValue *l, const TValue *r) { 487 lua_assert(ttisnumber(l) && ttisnumber(r)); 488 if (ttisinteger(l)) { 489 lua_Integer li = ivalue(l); 490 if (ttisinteger(r)) 491 return li < ivalue(r); /* both are integers */ 492 else /* 'l' is int and 'r' is float */ 493 return LTintfloat(li, fltvalue(r)); /* l < r ? */ 494 } 495 else { 496 lua_Number lf = fltvalue(l); /* 'l' must be float */ 497 if (ttisfloat(r)) 498 return luai_numlt(lf, fltvalue(r)); /* both are float */ 499 else /* 'l' is float and 'r' is int */ 500 return LTfloatint(lf, ivalue(r)); 501 } 502 } 503 504 505 /* 506 ** Return 'l <= r', for numbers. 507 */ 508 static int LEnum (const TValue *l, const TValue *r) { 509 lua_assert(ttisnumber(l) && ttisnumber(r)); 510 if (ttisinteger(l)) { 511 lua_Integer li = ivalue(l); 512 if (ttisinteger(r)) 513 return li <= ivalue(r); /* both are integers */ 514 else /* 'l' is int and 'r' is float */ 515 return LEintfloat(li, fltvalue(r)); /* l <= r ? */ 516 } 517 else { 518 lua_Number lf = fltvalue(l); /* 'l' must be float */ 519 if (ttisfloat(r)) 520 return luai_numle(lf, fltvalue(r)); /* both are float */ 521 else /* 'l' is float and 'r' is int */ 522 return LEfloatint(lf, ivalue(r)); 523 } 524 } 525 526 527 /* 528 ** return 'l < r' for non-numbers. 529 */ 530 static int lessthanothers (lua_State *L, const TValue *l, const TValue *r) { 531 lua_assert(!ttisnumber(l) || !ttisnumber(r)); 532 if (ttisstring(l) && ttisstring(r)) /* both are strings? */ 533 return l_strcmp(tsvalue(l), tsvalue(r)) < 0; 534 else 535 return luaT_callorderTM(L, l, r, TM_LT); 536 } 537 538 539 /* 540 ** Main operation less than; return 'l < r'. 541 */ 542 int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) { 543 if (ttisnumber(l) && ttisnumber(r)) /* both operands are numbers? */ 544 return LTnum(l, r); 545 else return lessthanothers(L, l, r); 546 } 547 548 549 /* 550 ** return 'l <= r' for non-numbers. 551 */ 552 static int lessequalothers (lua_State *L, const TValue *l, const TValue *r) { 553 lua_assert(!ttisnumber(l) || !ttisnumber(r)); 554 if (ttisstring(l) && ttisstring(r)) /* both are strings? */ 555 return l_strcmp(tsvalue(l), tsvalue(r)) <= 0; 556 else 557 return luaT_callorderTM(L, l, r, TM_LE); 558 } 559 560 561 /* 562 ** Main operation less than or equal to; return 'l <= r'. 563 */ 564 int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r) { 565 if (ttisnumber(l) && ttisnumber(r)) /* both operands are numbers? */ 566 return LEnum(l, r); 567 else return lessequalothers(L, l, r); 568 } 569 570 571 /* 572 ** Main operation for equality of Lua values; return 't1 == t2'. 573 ** L == NULL means raw equality (no metamethods) 574 */ 575 int luaV_equalobj (lua_State *L, const TValue *t1, const TValue *t2) { 576 const TValue *tm; 577 if (ttypetag(t1) != ttypetag(t2)) { /* not the same variant? */ 578 if (ttype(t1) != ttype(t2) || ttype(t1) != LUA_TNUMBER) 579 return 0; /* only numbers can be equal with different variants */ 580 else { /* two numbers with different variants */ 581 lua_Integer i1, i2; /* compare them as integers */ 582 return (tointegerns(t1, &i1) && tointegerns(t2, &i2) && i1 == i2); 583 } 584 } 585 /* values have same type and same variant */ 586 switch (ttypetag(t1)) { 587 case LUA_VNIL: case LUA_VFALSE: case LUA_VTRUE: return 1; 588 case LUA_VNUMINT: return (ivalue(t1) == ivalue(t2)); 589 case LUA_VNUMFLT: return luai_numeq(fltvalue(t1), fltvalue(t2)); 590 case LUA_VLIGHTUSERDATA: return pvalue(t1) == pvalue(t2); 591 case LUA_VLCF: return fvalue(t1) == fvalue(t2); 592 case LUA_VSHRSTR: return eqshrstr(tsvalue(t1), tsvalue(t2)); 593 case LUA_VLNGSTR: return luaS_eqlngstr(tsvalue(t1), tsvalue(t2)); 594 case LUA_VUSERDATA: { 595 if (uvalue(t1) == uvalue(t2)) return 1; 596 else if (L == NULL) return 0; 597 tm = fasttm(L, uvalue(t1)->metatable, TM_EQ); 598 if (tm == NULL) 599 tm = fasttm(L, uvalue(t2)->metatable, TM_EQ); 600 break; /* will try TM */ 601 } 602 case LUA_VTABLE: { 603 if (hvalue(t1) == hvalue(t2)) return 1; 604 else if (L == NULL) return 0; 605 tm = fasttm(L, hvalue(t1)->metatable, TM_EQ); 606 if (tm == NULL) 607 tm = fasttm(L, hvalue(t2)->metatable, TM_EQ); 608 break; /* will try TM */ 609 } 610 default: 611 return gcvalue(t1) == gcvalue(t2); 612 } 613 if (tm == NULL) /* no TM? */ 614 return 0; /* objects are different */ 615 else { 616 luaT_callTMres(L, tm, t1, t2, L->top); /* call TM */ 617 return !l_isfalse(s2v(L->top)); 618 } 619 } 620 621 622 /* macro used by 'luaV_concat' to ensure that element at 'o' is a string */ 623 #define tostring(L,o) \ 624 (ttisstring(o) || (cvt2str(o) && (luaO_tostring(L, o), 1))) 625 626 #define isemptystr(o) (ttisshrstring(o) && tsvalue(o)->shrlen == 0) 627 628 /* copy strings in stack from top - n up to top - 1 to buffer */ 629 static void copy2buff (StkId top, int n, char *buff) { 630 size_t tl = 0; /* size already copied */ 631 do { 632 size_t l = vslen(s2v(top - n)); /* length of string being copied */ 633 memcpy(buff + tl, svalue(s2v(top - n)), l * sizeof(char)); 634 tl += l; 635 } while (--n > 0); 636 } 637 638 639 /* 640 ** Main operation for concatenation: concat 'total' values in the stack, 641 ** from 'L->top - total' up to 'L->top - 1'. 642 */ 643 void luaV_concat (lua_State *L, int total) { 644 if (total == 1) 645 return; /* "all" values already concatenated */ 646 do { 647 StkId top = L->top; 648 int n = 2; /* number of elements handled in this pass (at least 2) */ 649 if (!(ttisstring(s2v(top - 2)) || cvt2str(s2v(top - 2))) || 650 !tostring(L, s2v(top - 1))) 651 luaT_tryconcatTM(L); 652 else if (isemptystr(s2v(top - 1))) /* second operand is empty? */ 653 cast_void(tostring(L, s2v(top - 2))); /* result is first operand */ 654 else if (isemptystr(s2v(top - 2))) { /* first operand is empty string? */ 655 setobjs2s(L, top - 2, top - 1); /* result is second op. */ 656 } 657 else { 658 /* at least two non-empty string values; get as many as possible */ 659 size_t tl = vslen(s2v(top - 1)); 660 TString *ts; 661 /* collect total length and number of strings */ 662 for (n = 1; n < total && tostring(L, s2v(top - n - 1)); n++) { 663 size_t l = vslen(s2v(top - n - 1)); 664 if (unlikely(l >= (MAX_SIZE/sizeof(char)) - tl)) 665 luaG_runerror(L, "string length overflow"); 666 tl += l; 667 } 668 if (tl <= LUAI_MAXSHORTLEN) { /* is result a short string? */ 669 char buff[LUAI_MAXSHORTLEN]; 670 copy2buff(top, n, buff); /* copy strings to buffer */ 671 ts = luaS_newlstr(L, buff, tl); 672 } 673 else { /* long string; copy strings directly to final result */ 674 ts = luaS_createlngstrobj(L, tl); 675 copy2buff(top, n, getstr(ts)); 676 } 677 setsvalue2s(L, top - n, ts); /* create result */ 678 } 679 total -= n-1; /* got 'n' strings to create 1 new */ 680 L->top -= n-1; /* popped 'n' strings and pushed one */ 681 } while (total > 1); /* repeat until only 1 result left */ 682 } 683 684 685 /* 686 ** Main operation 'ra = #rb'. 687 */ 688 void luaV_objlen (lua_State *L, StkId ra, const TValue *rb) { 689 const TValue *tm; 690 switch (ttypetag(rb)) { 691 case LUA_VTABLE: { 692 Table *h = hvalue(rb); 693 tm = fasttm(L, h->metatable, TM_LEN); 694 if (tm) break; /* metamethod? break switch to call it */ 695 setivalue(s2v(ra), luaH_getn(h)); /* else primitive len */ 696 return; 697 } 698 case LUA_VSHRSTR: { 699 setivalue(s2v(ra), tsvalue(rb)->shrlen); 700 return; 701 } 702 case LUA_VLNGSTR: { 703 setivalue(s2v(ra), tsvalue(rb)->u.lnglen); 704 return; 705 } 706 default: { /* try metamethod */ 707 tm = luaT_gettmbyobj(L, rb, TM_LEN); 708 if (unlikely(notm(tm))) /* no metamethod? */ 709 luaG_typeerror(L, rb, "get length of"); 710 break; 711 } 712 } 713 luaT_callTMres(L, tm, rb, rb, ra); 714 } 715 716 717 /* 718 ** Integer division; return 'm // n', that is, floor(m/n). 719 ** C division truncates its result (rounds towards zero). 720 ** 'floor(q) == trunc(q)' when 'q >= 0' or when 'q' is integer, 721 ** otherwise 'floor(q) == trunc(q) - 1'. 722 */ 723 lua_Integer luaV_idiv (lua_State *L, lua_Integer m, lua_Integer n) { 724 if (unlikely(l_castS2U(n) + 1u <= 1u)) { /* special cases: -1 or 0 */ 725 if (n == 0) 726 luaG_runerror(L, "attempt to divide by zero"); 727 return intop(-, 0, m); /* n==-1; avoid overflow with 0x80000...//-1 */ 728 } 729 else { 730 lua_Integer q = m / n; /* perform C division */ 731 if ((m ^ n) < 0 && m % n != 0) /* 'm/n' would be negative non-integer? */ 732 q -= 1; /* correct result for different rounding */ 733 return q; 734 } 735 } 736 737 738 /* 739 ** Integer modulus; return 'm % n'. (Assume that C '%' with 740 ** negative operands follows C99 behavior. See previous comment 741 ** about luaV_idiv.) 742 */ 743 lua_Integer luaV_mod (lua_State *L, lua_Integer m, lua_Integer n) { 744 if (unlikely(l_castS2U(n) + 1u <= 1u)) { /* special cases: -1 or 0 */ 745 if (n == 0) 746 luaG_runerror(L, "attempt to perform 'n%%0'"); 747 return 0; /* m % -1 == 0; avoid overflow with 0x80000...%-1 */ 748 } 749 else { 750 lua_Integer r = m % n; 751 if (r != 0 && (r ^ n) < 0) /* 'm/n' would be non-integer negative? */ 752 r += n; /* correct result for different rounding */ 753 return r; 754 } 755 } 756 757 758 /* 759 ** Float modulus 760 */ 761 lua_Number luaV_modf (lua_State *L, lua_Number m, lua_Number n) { 762 lua_Number r; 763 luai_nummod(L, m, n, r); 764 return r; 765 } 766 767 768 /* number of bits in an integer */ 769 #define NBITS cast_int(sizeof(lua_Integer) * CHAR_BIT) 770 771 /* 772 ** Shift left operation. (Shift right just negates 'y'.) 773 */ 774 #define luaV_shiftr(x,y) luaV_shiftl(x,-(y)) 775 776 lua_Integer luaV_shiftl (lua_Integer x, lua_Integer y) { 777 if (y < 0) { /* shift right? */ 778 if (y <= -NBITS) return 0; 779 else return intop(>>, x, -y); 780 } 781 else { /* shift left */ 782 if (y >= NBITS) return 0; 783 else return intop(<<, x, y); 784 } 785 } 786 787 788 /* 789 ** create a new Lua closure, push it in the stack, and initialize 790 ** its upvalues. 791 */ 792 static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base, 793 StkId ra) { 794 int nup = p->sizeupvalues; 795 Upvaldesc *uv = p->upvalues; 796 int i; 797 LClosure *ncl = luaF_newLclosure(L, nup); 798 ncl->p = p; 799 setclLvalue2s(L, ra, ncl); /* anchor new closure in stack */ 800 for (i = 0; i < nup; i++) { /* fill in its upvalues */ 801 if (uv[i].instack) /* upvalue refers to local variable? */ 802 ncl->upvals[i] = luaF_findupval(L, base + uv[i].idx); 803 else /* get upvalue from enclosing function */ 804 ncl->upvals[i] = encup[uv[i].idx]; 805 luaC_objbarrier(L, ncl, ncl->upvals[i]); 806 } 807 } 808 809 810 /* 811 ** finish execution of an opcode interrupted by a yield 812 */ 813 void luaV_finishOp (lua_State *L) { 814 CallInfo *ci = L->ci; 815 StkId base = ci->func + 1; 816 Instruction inst = *(ci->u.l.savedpc - 1); /* interrupted instruction */ 817 OpCode op = GET_OPCODE(inst); 818 switch (op) { /* finish its execution */ 819 case OP_MMBIN: case OP_MMBINI: case OP_MMBINK: { 820 setobjs2s(L, base + GETARG_A(*(ci->u.l.savedpc - 2)), --L->top); 821 break; 822 } 823 case OP_UNM: case OP_BNOT: case OP_LEN: 824 case OP_GETTABUP: case OP_GETTABLE: case OP_GETI: 825 case OP_GETFIELD: case OP_SELF: { 826 setobjs2s(L, base + GETARG_A(inst), --L->top); 827 break; 828 } 829 case OP_LT: case OP_LE: 830 case OP_LTI: case OP_LEI: 831 case OP_GTI: case OP_GEI: 832 case OP_EQ: { /* note that 'OP_EQI'/'OP_EQK' cannot yield */ 833 int res = !l_isfalse(s2v(L->top - 1)); 834 L->top--; 835 #if defined(LUA_COMPAT_LT_LE) 836 if (ci->callstatus & CIST_LEQ) { /* "<=" using "<" instead? */ 837 ci->callstatus ^= CIST_LEQ; /* clear mark */ 838 res = !res; /* negate result */ 839 } 840 #endif 841 lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_JMP); 842 if (res != GETARG_k(inst)) /* condition failed? */ 843 ci->u.l.savedpc++; /* skip jump instruction */ 844 break; 845 } 846 case OP_CONCAT: { 847 StkId top = L->top - 1; /* top when 'luaT_tryconcatTM' was called */ 848 int a = GETARG_A(inst); /* first element to concatenate */ 849 int total = cast_int(top - 1 - (base + a)); /* yet to concatenate */ 850 setobjs2s(L, top - 2, top); /* put TM result in proper position */ 851 L->top = top - 1; /* top is one after last element (at top-2) */ 852 luaV_concat(L, total); /* concat them (may yield again) */ 853 break; 854 } 855 default: { 856 /* only these other opcodes can yield */ 857 lua_assert(op == OP_TFORCALL || op == OP_CALL || 858 op == OP_TAILCALL || op == OP_SETTABUP || op == OP_SETTABLE || 859 op == OP_SETI || op == OP_SETFIELD); 860 break; 861 } 862 } 863 } 864 865 866 867 868 /* 869 ** {================================================================== 870 ** Macros for arithmetic/bitwise/comparison opcodes in 'luaV_execute' 871 ** =================================================================== 872 */ 873 874 #define l_addi(L,a,b) intop(+, a, b) 875 #define l_subi(L,a,b) intop(-, a, b) 876 #define l_muli(L,a,b) intop(*, a, b) 877 #define l_band(a,b) intop(&, a, b) 878 #define l_bor(a,b) intop(|, a, b) 879 #define l_bxor(a,b) intop(^, a, b) 880 881 #define l_lti(a,b) (a < b) 882 #define l_lei(a,b) (a <= b) 883 #define l_gti(a,b) (a > b) 884 #define l_gei(a,b) (a >= b) 885 886 887 /* 888 ** Arithmetic operations with immediate operands. 'iop' is the integer 889 ** operation, 'fop' is the float operation. 890 */ 891 #define op_arithI(L,iop,fop) { \ 892 TValue *v1 = vRB(i); \ 893 int imm = GETARG_sC(i); \ 894 if (ttisinteger(v1)) { \ 895 lua_Integer iv1 = ivalue(v1); \ 896 pc++; setivalue(s2v(ra), iop(L, iv1, imm)); \ 897 } \ 898 else if (ttisfloat(v1)) { \ 899 lua_Number nb = fltvalue(v1); \ 900 lua_Number fimm = cast_num(imm); \ 901 pc++; setfltvalue(s2v(ra), fop(L, nb, fimm)); \ 902 }} 903 904 905 /* 906 ** Auxiliary function for arithmetic operations over floats and others 907 ** with two register operands. 908 */ 909 #define op_arithf_aux(L,v1,v2,fop) { \ 910 lua_Number n1; lua_Number n2; \ 911 if (tonumberns(v1, n1) && tonumberns(v2, n2)) { \ 912 pc++; setfltvalue(s2v(ra), fop(L, n1, n2)); \ 913 }} 914 915 916 /* 917 ** Arithmetic operations over floats and others with register operands. 918 */ 919 #define op_arithf(L,fop) { \ 920 TValue *v1 = vRB(i); \ 921 TValue *v2 = vRC(i); \ 922 op_arithf_aux(L, v1, v2, fop); } 923 924 925 /* 926 ** Arithmetic operations with K operands for floats. 927 */ 928 #define op_arithfK(L,fop) { \ 929 TValue *v1 = vRB(i); \ 930 TValue *v2 = KC(i); \ 931 op_arithf_aux(L, v1, v2, fop); } 932 933 934 /* 935 ** Arithmetic operations over integers and floats. 936 */ 937 #define op_arith_aux(L,v1,v2,iop,fop) { \ 938 if (ttisinteger(v1) && ttisinteger(v2)) { \ 939 lua_Integer i1 = ivalue(v1); lua_Integer i2 = ivalue(v2); \ 940 pc++; setivalue(s2v(ra), iop(L, i1, i2)); \ 941 } \ 942 else op_arithf_aux(L, v1, v2, fop); } 943 944 945 /* 946 ** Arithmetic operations with register operands. 947 */ 948 #define op_arith(L,iop,fop) { \ 949 TValue *v1 = vRB(i); \ 950 TValue *v2 = vRC(i); \ 951 op_arith_aux(L, v1, v2, iop, fop); } 952 953 954 /* 955 ** Arithmetic operations with K operands. 956 */ 957 #define op_arithK(L,iop,fop) { \ 958 TValue *v1 = vRB(i); \ 959 TValue *v2 = KC(i); \ 960 op_arith_aux(L, v1, v2, iop, fop); } 961 962 963 /* 964 ** Bitwise operations with constant operand. 965 */ 966 #define op_bitwiseK(L,op) { \ 967 TValue *v1 = vRB(i); \ 968 TValue *v2 = KC(i); \ 969 lua_Integer i1; \ 970 lua_Integer i2 = ivalue(v2); \ 971 if (tointegerns(v1, &i1)) { \ 972 pc++; setivalue(s2v(ra), op(i1, i2)); \ 973 }} 974 975 976 /* 977 ** Bitwise operations with register operands. 978 */ 979 #define op_bitwise(L,op) { \ 980 TValue *v1 = vRB(i); \ 981 TValue *v2 = vRC(i); \ 982 lua_Integer i1; lua_Integer i2; \ 983 if (tointegerns(v1, &i1) && tointegerns(v2, &i2)) { \ 984 pc++; setivalue(s2v(ra), op(i1, i2)); \ 985 }} 986 987 988 /* 989 ** Order operations with register operands. 'opn' actually works 990 ** for all numbers, but the fast track improves performance for 991 ** integers. 992 */ 993 #define op_order(L,opi,opn,other) { \ 994 int cond; \ 995 TValue *rb = vRB(i); \ 996 if (ttisinteger(s2v(ra)) && ttisinteger(rb)) { \ 997 lua_Integer ia = ivalue(s2v(ra)); \ 998 lua_Integer ib = ivalue(rb); \ 999 cond = opi(ia, ib); \ 1000 } \ 1001 else if (ttisnumber(s2v(ra)) && ttisnumber(rb)) \ 1002 cond = opn(s2v(ra), rb); \ 1003 else \ 1004 Protect(cond = other(L, s2v(ra), rb)); \ 1005 docondjump(); } 1006 1007 1008 /* 1009 ** Order operations with immediate operand. (Immediate operand is 1010 ** always small enough to have an exact representation as a float.) 1011 */ 1012 #define op_orderI(L,opi,opf,inv,tm) { \ 1013 int cond; \ 1014 int im = GETARG_sB(i); \ 1015 if (ttisinteger(s2v(ra))) \ 1016 cond = opi(ivalue(s2v(ra)), im); \ 1017 else if (ttisfloat(s2v(ra))) { \ 1018 lua_Number fa = fltvalue(s2v(ra)); \ 1019 lua_Number fim = cast_num(im); \ 1020 cond = opf(fa, fim); \ 1021 } \ 1022 else { \ 1023 int isf = GETARG_C(i); \ 1024 Protect(cond = luaT_callorderiTM(L, s2v(ra), im, inv, isf, tm)); \ 1025 } \ 1026 docondjump(); } 1027 1028 /* }================================================================== */ 1029 1030 1031 /* 1032 ** {================================================================== 1033 ** Function 'luaV_execute': main interpreter loop 1034 ** =================================================================== 1035 */ 1036 1037 /* 1038 ** some macros for common tasks in 'luaV_execute' 1039 */ 1040 1041 1042 #define RA(i) (base+GETARG_A(i)) 1043 #define RB(i) (base+GETARG_B(i)) 1044 #define vRB(i) s2v(RB(i)) 1045 #define KB(i) (k+GETARG_B(i)) 1046 #define RC(i) (base+GETARG_C(i)) 1047 #define vRC(i) s2v(RC(i)) 1048 #define KC(i) (k+GETARG_C(i)) 1049 #define RKC(i) ((TESTARG_k(i)) ? k + GETARG_C(i) : s2v(base + GETARG_C(i))) 1050 1051 1052 1053 #define updatetrap(ci) (trap = ci->u.l.trap) 1054 1055 #define updatebase(ci) (base = ci->func + 1) 1056 1057 1058 #define updatestack(ci) { if (trap) { updatebase(ci); ra = RA(i); } } 1059 1060 1061 /* 1062 ** Execute a jump instruction. The 'updatetrap' allows signals to stop 1063 ** tight loops. (Without it, the local copy of 'trap' could never change.) 1064 */ 1065 #define dojump(ci,i,e) { pc += GETARG_sJ(i) + e; updatetrap(ci); } 1066 1067 1068 /* for test instructions, execute the jump instruction that follows it */ 1069 #define donextjump(ci) { Instruction ni = *pc; dojump(ci, ni, 1); } 1070 1071 /* 1072 ** do a conditional jump: skip next instruction if 'cond' is not what 1073 ** was expected (parameter 'k'), else do next instruction, which must 1074 ** be a jump. 1075 */ 1076 #define docondjump() if (cond != GETARG_k(i)) pc++; else donextjump(ci); 1077 1078 1079 /* 1080 ** Correct global 'pc'. 1081 */ 1082 #define savepc(L) (ci->u.l.savedpc = pc) 1083 1084 1085 /* 1086 ** Whenever code can raise errors, the global 'pc' and the global 1087 ** 'top' must be correct to report occasional errors. 1088 */ 1089 #define savestate(L,ci) (savepc(L), L->top = ci->top) 1090 1091 1092 /* 1093 ** Protect code that, in general, can raise errors, reallocate the 1094 ** stack, and change the hooks. 1095 */ 1096 #define Protect(exp) (savestate(L,ci), (exp), updatetrap(ci)) 1097 1098 /* special version that does not change the top */ 1099 #define ProtectNT(exp) (savepc(L), (exp), updatetrap(ci)) 1100 1101 /* 1102 ** Protect code that can only raise errors. (That is, it cannnot change 1103 ** the stack or hooks.) 1104 */ 1105 #define halfProtect(exp) (savestate(L,ci), (exp)) 1106 1107 /* 'c' is the limit of live values in the stack */ 1108 #define checkGC(L,c) \ 1109 { luaC_condGC(L, (savepc(L), L->top = (c)), \ 1110 updatetrap(ci)); \ 1111 luai_threadyield(L); } 1112 1113 1114 /* fetch an instruction and prepare its execution */ 1115 #define vmfetch() { \ 1116 if (trap) { /* stack reallocation or hooks? */ \ 1117 trap = luaG_traceexec(L, pc); /* handle hooks */ \ 1118 updatebase(ci); /* correct stack */ \ 1119 } \ 1120 i = *(pc++); \ 1121 ra = RA(i); /* WARNING: any stack reallocation invalidates 'ra' */ \ 1122 } 1123 1124 #define vmdispatch(o) switch(o) 1125 #define vmcase(l) case l: 1126 #define vmbreak break 1127 1128 1129 void luaV_execute (lua_State *L, CallInfo *ci) { 1130 LClosure *cl; 1131 TValue *k; 1132 StkId base; 1133 const Instruction *pc; 1134 int trap; 1135 #if LUA_USE_JUMPTABLE 1136 #include "ljumptab.h" 1137 #endif 1138 startfunc: 1139 trap = L->hookmask; 1140 returning: /* trap already set */ 1141 cl = clLvalue(s2v(ci->func)); 1142 k = cl->p->k; 1143 pc = ci->u.l.savedpc; 1144 if (trap) { 1145 if (pc == cl->p->code) { /* first instruction (not resuming)? */ 1146 if (cl->p->is_vararg) 1147 trap = 0; /* hooks will start after VARARGPREP instruction */ 1148 else /* check 'call' hook */ 1149 luaD_hookcall(L, ci); 1150 } 1151 ci->u.l.trap = 1; /* assume trap is on, for now */ 1152 } 1153 base = ci->func + 1; 1154 /* main loop of interpreter */ 1155 for (;;) { 1156 Instruction i; /* instruction being executed */ 1157 StkId ra; /* instruction's A register */ 1158 vmfetch(); 1159 lua_assert(base == ci->func + 1); 1160 lua_assert(base <= L->top && L->top < L->stack_last); 1161 /* invalidate top for instructions not expecting it */ 1162 lua_assert(isIT(i) || (cast_void(L->top = base), 1)); 1163 vmdispatch (GET_OPCODE(i)) { 1164 vmcase(OP_MOVE) { 1165 setobjs2s(L, ra, RB(i)); 1166 vmbreak; 1167 } 1168 vmcase(OP_LOADI) { 1169 lua_Integer b = GETARG_sBx(i); 1170 setivalue(s2v(ra), b); 1171 vmbreak; 1172 } 1173 vmcase(OP_LOADF) { 1174 int b = GETARG_sBx(i); 1175 setfltvalue(s2v(ra), cast_num(b)); 1176 vmbreak; 1177 } 1178 vmcase(OP_LOADK) { 1179 TValue *rb = k + GETARG_Bx(i); 1180 setobj2s(L, ra, rb); 1181 vmbreak; 1182 } 1183 vmcase(OP_LOADKX) { 1184 TValue *rb; 1185 rb = k + GETARG_Ax(*pc); pc++; 1186 setobj2s(L, ra, rb); 1187 vmbreak; 1188 } 1189 vmcase(OP_LOADFALSE) { 1190 setbfvalue(s2v(ra)); 1191 vmbreak; 1192 } 1193 vmcase(OP_LFALSESKIP) { 1194 setbfvalue(s2v(ra)); 1195 pc++; /* skip next instruction */ 1196 vmbreak; 1197 } 1198 vmcase(OP_LOADTRUE) { 1199 setbtvalue(s2v(ra)); 1200 vmbreak; 1201 } 1202 vmcase(OP_LOADNIL) { 1203 int b = GETARG_B(i); 1204 do { 1205 setnilvalue(s2v(ra++)); 1206 } while (b--); 1207 vmbreak; 1208 } 1209 vmcase(OP_GETUPVAL) { 1210 int b = GETARG_B(i); 1211 setobj2s(L, ra, cl->upvals[b]->v); 1212 vmbreak; 1213 } 1214 vmcase(OP_SETUPVAL) { 1215 UpVal *uv = cl->upvals[GETARG_B(i)]; 1216 setobj(L, uv->v, s2v(ra)); 1217 luaC_barrier(L, uv, s2v(ra)); 1218 vmbreak; 1219 } 1220 vmcase(OP_GETTABUP) { 1221 const TValue *slot; 1222 TValue *upval = cl->upvals[GETARG_B(i)]->v; 1223 TValue *rc = KC(i); 1224 TString *key = tsvalue(rc); /* key must be a string */ 1225 if (luaV_fastget(L, upval, key, slot, luaH_getshortstr)) { 1226 setobj2s(L, ra, slot); 1227 } 1228 else 1229 Protect(luaV_finishget(L, upval, rc, ra, slot)); 1230 vmbreak; 1231 } 1232 vmcase(OP_GETTABLE) { 1233 const TValue *slot; 1234 TValue *rb = vRB(i); 1235 TValue *rc = vRC(i); 1236 lua_Unsigned n; 1237 if (ttisinteger(rc) /* fast track for integers? */ 1238 ? (cast_void(n = ivalue(rc)), luaV_fastgeti(L, rb, n, slot)) 1239 : luaV_fastget(L, rb, rc, slot, luaH_get)) { 1240 setobj2s(L, ra, slot); 1241 } 1242 else 1243 Protect(luaV_finishget(L, rb, rc, ra, slot)); 1244 vmbreak; 1245 } 1246 vmcase(OP_GETI) { 1247 const TValue *slot; 1248 TValue *rb = vRB(i); 1249 int c = GETARG_C(i); 1250 if (luaV_fastgeti(L, rb, c, slot)) { 1251 setobj2s(L, ra, slot); 1252 } 1253 else { 1254 TValue key; 1255 setivalue(&key, c); 1256 Protect(luaV_finishget(L, rb, &key, ra, slot)); 1257 } 1258 vmbreak; 1259 } 1260 vmcase(OP_GETFIELD) { 1261 const TValue *slot; 1262 TValue *rb = vRB(i); 1263 TValue *rc = KC(i); 1264 TString *key = tsvalue(rc); /* key must be a string */ 1265 if (luaV_fastget(L, rb, key, slot, luaH_getshortstr)) { 1266 setobj2s(L, ra, slot); 1267 } 1268 else 1269 Protect(luaV_finishget(L, rb, rc, ra, slot)); 1270 vmbreak; 1271 } 1272 vmcase(OP_SETTABUP) { 1273 const TValue *slot; 1274 TValue *upval = cl->upvals[GETARG_A(i)]->v; 1275 TValue *rb = KB(i); 1276 TValue *rc = RKC(i); 1277 TString *key = tsvalue(rb); /* key must be a string */ 1278 if (luaV_fastget(L, upval, key, slot, luaH_getshortstr)) { 1279 luaV_finishfastset(L, upval, slot, rc); 1280 } 1281 else 1282 Protect(luaV_finishset(L, upval, rb, rc, slot)); 1283 vmbreak; 1284 } 1285 vmcase(OP_SETTABLE) { 1286 const TValue *slot; 1287 TValue *rb = vRB(i); /* key (table is in 'ra') */ 1288 TValue *rc = RKC(i); /* value */ 1289 lua_Unsigned n; 1290 if (ttisinteger(rb) /* fast track for integers? */ 1291 ? (cast_void(n = ivalue(rb)), luaV_fastgeti(L, s2v(ra), n, slot)) 1292 : luaV_fastget(L, s2v(ra), rb, slot, luaH_get)) { 1293 luaV_finishfastset(L, s2v(ra), slot, rc); 1294 } 1295 else 1296 Protect(luaV_finishset(L, s2v(ra), rb, rc, slot)); 1297 vmbreak; 1298 } 1299 vmcase(OP_SETI) { 1300 const TValue *slot; 1301 int c = GETARG_B(i); 1302 TValue *rc = RKC(i); 1303 if (luaV_fastgeti(L, s2v(ra), c, slot)) { 1304 luaV_finishfastset(L, s2v(ra), slot, rc); 1305 } 1306 else { 1307 TValue key; 1308 setivalue(&key, c); 1309 Protect(luaV_finishset(L, s2v(ra), &key, rc, slot)); 1310 } 1311 vmbreak; 1312 } 1313 vmcase(OP_SETFIELD) { 1314 const TValue *slot; 1315 TValue *rb = KB(i); 1316 TValue *rc = RKC(i); 1317 TString *key = tsvalue(rb); /* key must be a string */ 1318 if (luaV_fastget(L, s2v(ra), key, slot, luaH_getshortstr)) { 1319 luaV_finishfastset(L, s2v(ra), slot, rc); 1320 } 1321 else 1322 Protect(luaV_finishset(L, s2v(ra), rb, rc, slot)); 1323 vmbreak; 1324 } 1325 vmcase(OP_NEWTABLE) { 1326 int b = GETARG_B(i); /* log2(hash size) + 1 */ 1327 int c = GETARG_C(i); /* array size */ 1328 Table *t; 1329 if (b > 0) 1330 b = 1 << (b - 1); /* size is 2^(b - 1) */ 1331 lua_assert((!TESTARG_k(i)) == (GETARG_Ax(*pc) == 0)); 1332 if (TESTARG_k(i)) /* non-zero extra argument? */ 1333 c += GETARG_Ax(*pc) * (MAXARG_C + 1); /* add it to size */ 1334 pc++; /* skip extra argument */ 1335 L->top = ra + 1; /* correct top in case of emergency GC */ 1336 t = luaH_new(L); /* memory allocation */ 1337 sethvalue2s(L, ra, t); 1338 if (b != 0 || c != 0) 1339 luaH_resize(L, t, c, b); /* idem */ 1340 checkGC(L, ra + 1); 1341 vmbreak; 1342 } 1343 vmcase(OP_SELF) { 1344 const TValue *slot; 1345 TValue *rb = vRB(i); 1346 TValue *rc = RKC(i); 1347 TString *key = tsvalue(rc); /* key must be a string */ 1348 setobj2s(L, ra + 1, rb); 1349 if (luaV_fastget(L, rb, key, slot, luaH_getstr)) { 1350 setobj2s(L, ra, slot); 1351 } 1352 else 1353 Protect(luaV_finishget(L, rb, rc, ra, slot)); 1354 vmbreak; 1355 } 1356 vmcase(OP_ADDI) { 1357 op_arithI(L, l_addi, luai_numadd); 1358 vmbreak; 1359 } 1360 vmcase(OP_ADDK) { 1361 op_arithK(L, l_addi, luai_numadd); 1362 vmbreak; 1363 } 1364 vmcase(OP_SUBK) { 1365 op_arithK(L, l_subi, luai_numsub); 1366 vmbreak; 1367 } 1368 vmcase(OP_MULK) { 1369 op_arithK(L, l_muli, luai_nummul); 1370 vmbreak; 1371 } 1372 vmcase(OP_MODK) { 1373 op_arithK(L, luaV_mod, luaV_modf); 1374 vmbreak; 1375 } 1376 vmcase(OP_POWK) { 1377 op_arithfK(L, luai_numpow); 1378 vmbreak; 1379 } 1380 vmcase(OP_DIVK) { 1381 op_arithfK(L, luai_numdiv); 1382 vmbreak; 1383 } 1384 vmcase(OP_IDIVK) { 1385 op_arithK(L, luaV_idiv, luai_numidiv); 1386 vmbreak; 1387 } 1388 vmcase(OP_BANDK) { 1389 op_bitwiseK(L, l_band); 1390 vmbreak; 1391 } 1392 vmcase(OP_BORK) { 1393 op_bitwiseK(L, l_bor); 1394 vmbreak; 1395 } 1396 vmcase(OP_BXORK) { 1397 op_bitwiseK(L, l_bxor); 1398 vmbreak; 1399 } 1400 vmcase(OP_SHRI) { 1401 TValue *rb = vRB(i); 1402 int ic = GETARG_sC(i); 1403 lua_Integer ib; 1404 if (tointegerns(rb, &ib)) { 1405 pc++; setivalue(s2v(ra), luaV_shiftl(ib, -ic)); 1406 } 1407 vmbreak; 1408 } 1409 vmcase(OP_SHLI) { 1410 TValue *rb = vRB(i); 1411 int ic = GETARG_sC(i); 1412 lua_Integer ib; 1413 if (tointegerns(rb, &ib)) { 1414 pc++; setivalue(s2v(ra), luaV_shiftl(ic, ib)); 1415 } 1416 vmbreak; 1417 } 1418 vmcase(OP_ADD) { 1419 op_arith(L, l_addi, luai_numadd); 1420 vmbreak; 1421 } 1422 vmcase(OP_SUB) { 1423 op_arith(L, l_subi, luai_numsub); 1424 vmbreak; 1425 } 1426 vmcase(OP_MUL) { 1427 op_arith(L, l_muli, luai_nummul); 1428 vmbreak; 1429 } 1430 vmcase(OP_MOD) { 1431 op_arith(L, luaV_mod, luaV_modf); 1432 vmbreak; 1433 } 1434 vmcase(OP_POW) { 1435 op_arithf(L, luai_numpow); 1436 vmbreak; 1437 } 1438 vmcase(OP_DIV) { /* float division (always with floats) */ 1439 op_arithf(L, luai_numdiv); 1440 vmbreak; 1441 } 1442 vmcase(OP_IDIV) { /* floor division */ 1443 op_arith(L, luaV_idiv, luai_numidiv); 1444 vmbreak; 1445 } 1446 vmcase(OP_BAND) { 1447 op_bitwise(L, l_band); 1448 vmbreak; 1449 } 1450 vmcase(OP_BOR) { 1451 op_bitwise(L, l_bor); 1452 vmbreak; 1453 } 1454 vmcase(OP_BXOR) { 1455 op_bitwise(L, l_bxor); 1456 vmbreak; 1457 } 1458 vmcase(OP_SHR) { 1459 op_bitwise(L, luaV_shiftr); 1460 vmbreak; 1461 } 1462 vmcase(OP_SHL) { 1463 op_bitwise(L, luaV_shiftl); 1464 vmbreak; 1465 } 1466 vmcase(OP_MMBIN) { 1467 Instruction pi = *(pc - 2); /* original arith. expression */ 1468 TValue *rb = vRB(i); 1469 TMS tm = (TMS)GETARG_C(i); 1470 StkId result = RA(pi); 1471 lua_assert(OP_ADD <= GET_OPCODE(pi) && GET_OPCODE(pi) <= OP_SHR); 1472 Protect(luaT_trybinTM(L, s2v(ra), rb, result, tm)); 1473 vmbreak; 1474 } 1475 vmcase(OP_MMBINI) { 1476 Instruction pi = *(pc - 2); /* original arith. expression */ 1477 int imm = GETARG_sB(i); 1478 TMS tm = (TMS)GETARG_C(i); 1479 int flip = GETARG_k(i); 1480 StkId result = RA(pi); 1481 Protect(luaT_trybiniTM(L, s2v(ra), imm, flip, result, tm)); 1482 vmbreak; 1483 } 1484 vmcase(OP_MMBINK) { 1485 Instruction pi = *(pc - 2); /* original arith. expression */ 1486 TValue *imm = KB(i); 1487 TMS tm = (TMS)GETARG_C(i); 1488 int flip = GETARG_k(i); 1489 StkId result = RA(pi); 1490 Protect(luaT_trybinassocTM(L, s2v(ra), imm, flip, result, tm)); 1491 vmbreak; 1492 } 1493 vmcase(OP_UNM) { 1494 TValue *rb = vRB(i); 1495 lua_Number nb; 1496 if (ttisinteger(rb)) { 1497 lua_Integer ib = ivalue(rb); 1498 setivalue(s2v(ra), intop(-, 0, ib)); 1499 } 1500 else if (tonumberns(rb, nb)) { 1501 setfltvalue(s2v(ra), luai_numunm(L, nb)); 1502 } 1503 else 1504 Protect(luaT_trybinTM(L, rb, rb, ra, TM_UNM)); 1505 vmbreak; 1506 } 1507 vmcase(OP_BNOT) { 1508 TValue *rb = vRB(i); 1509 lua_Integer ib; 1510 if (tointegerns(rb, &ib)) { 1511 setivalue(s2v(ra), intop(^, ~l_castS2U(0), ib)); 1512 } 1513 else 1514 Protect(luaT_trybinTM(L, rb, rb, ra, TM_BNOT)); 1515 vmbreak; 1516 } 1517 vmcase(OP_NOT) { 1518 TValue *rb = vRB(i); 1519 if (l_isfalse(rb)) 1520 setbtvalue(s2v(ra)); 1521 else 1522 setbfvalue(s2v(ra)); 1523 vmbreak; 1524 } 1525 vmcase(OP_LEN) { 1526 Protect(luaV_objlen(L, ra, vRB(i))); 1527 vmbreak; 1528 } 1529 vmcase(OP_CONCAT) { 1530 int n = GETARG_B(i); /* number of elements to concatenate */ 1531 L->top = ra + n; /* mark the end of concat operands */ 1532 ProtectNT(luaV_concat(L, n)); 1533 checkGC(L, L->top); /* 'luaV_concat' ensures correct top */ 1534 vmbreak; 1535 } 1536 vmcase(OP_CLOSE) { 1537 Protect(luaF_close(L, ra, LUA_OK)); 1538 vmbreak; 1539 } 1540 vmcase(OP_TBC) { 1541 /* create new to-be-closed upvalue */ 1542 halfProtect(luaF_newtbcupval(L, ra)); 1543 vmbreak; 1544 } 1545 vmcase(OP_JMP) { 1546 dojump(ci, i, 0); 1547 vmbreak; 1548 } 1549 vmcase(OP_EQ) { 1550 int cond; 1551 TValue *rb = vRB(i); 1552 Protect(cond = luaV_equalobj(L, s2v(ra), rb)); 1553 docondjump(); 1554 vmbreak; 1555 } 1556 vmcase(OP_LT) { 1557 op_order(L, l_lti, LTnum, lessthanothers); 1558 vmbreak; 1559 } 1560 vmcase(OP_LE) { 1561 op_order(L, l_lei, LEnum, lessequalothers); 1562 vmbreak; 1563 } 1564 vmcase(OP_EQK) { 1565 TValue *rb = KB(i); 1566 /* basic types do not use '__eq'; we can use raw equality */ 1567 int cond = luaV_rawequalobj(s2v(ra), rb); 1568 docondjump(); 1569 vmbreak; 1570 } 1571 vmcase(OP_EQI) { 1572 int cond; 1573 int im = GETARG_sB(i); 1574 if (ttisinteger(s2v(ra))) 1575 cond = (ivalue(s2v(ra)) == im); 1576 else if (ttisfloat(s2v(ra))) 1577 cond = luai_numeq(fltvalue(s2v(ra)), cast_num(im)); 1578 else 1579 cond = 0; /* other types cannot be equal to a number */ 1580 docondjump(); 1581 vmbreak; 1582 } 1583 vmcase(OP_LTI) { 1584 op_orderI(L, l_lti, luai_numlt, 0, TM_LT); 1585 vmbreak; 1586 } 1587 vmcase(OP_LEI) { 1588 op_orderI(L, l_lei, luai_numle, 0, TM_LE); 1589 vmbreak; 1590 } 1591 vmcase(OP_GTI) { 1592 op_orderI(L, l_gti, luai_numgt, 1, TM_LT); 1593 vmbreak; 1594 } 1595 vmcase(OP_GEI) { 1596 op_orderI(L, l_gei, luai_numge, 1, TM_LE); 1597 vmbreak; 1598 } 1599 vmcase(OP_TEST) { 1600 int cond = !l_isfalse(s2v(ra)); 1601 docondjump(); 1602 vmbreak; 1603 } 1604 vmcase(OP_TESTSET) { 1605 TValue *rb = vRB(i); 1606 if (l_isfalse(rb) == GETARG_k(i)) 1607 pc++; 1608 else { 1609 setobj2s(L, ra, rb); 1610 donextjump(ci); 1611 } 1612 vmbreak; 1613 } 1614 vmcase(OP_CALL) { 1615 CallInfo *newci; 1616 int b = GETARG_B(i); 1617 int nresults = GETARG_C(i) - 1; 1618 if (b != 0) /* fixed number of arguments? */ 1619 L->top = ra + b; /* top signals number of arguments */ 1620 /* else previous instruction set top */ 1621 savepc(L); /* in case of errors */ 1622 if ((newci = luaD_precall(L, ra, nresults)) == NULL) 1623 updatetrap(ci); /* C call; nothing else to be done */ 1624 else { /* Lua call: run function in this same C frame */ 1625 ci = newci; 1626 ci->callstatus = 0; /* call re-uses 'luaV_execute' */ 1627 goto startfunc; 1628 } 1629 vmbreak; 1630 } 1631 vmcase(OP_TAILCALL) { 1632 int b = GETARG_B(i); /* number of arguments + 1 (function) */ 1633 int nparams1 = GETARG_C(i); 1634 /* delta is virtual 'func' - real 'func' (vararg functions) */ 1635 int delta = (nparams1) ? ci->u.l.nextraargs + nparams1 : 0; 1636 if (b != 0) 1637 L->top = ra + b; 1638 else /* previous instruction set top */ 1639 b = cast_int(L->top - ra); 1640 savepc(ci); /* several calls here can raise errors */ 1641 if (TESTARG_k(i)) { 1642 /* close upvalues from current call; the compiler ensures 1643 that there are no to-be-closed variables here, so this 1644 call cannot change the stack */ 1645 luaF_close(L, base, NOCLOSINGMETH); 1646 lua_assert(base == ci->func + 1); 1647 } 1648 while (!ttisfunction(s2v(ra))) { /* not a function? */ 1649 luaD_tryfuncTM(L, ra); /* try '__call' metamethod */ 1650 b++; /* there is now one extra argument */ 1651 checkstackGCp(L, 1, ra); 1652 } 1653 if (!ttisLclosure(s2v(ra))) { /* C function? */ 1654 luaD_precall(L, ra, LUA_MULTRET); /* call it */ 1655 updatetrap(ci); 1656 updatestack(ci); /* stack may have been relocated */ 1657 ci->func -= delta; /* restore 'func' (if vararg) */ 1658 luaD_poscall(L, ci, cast_int(L->top - ra)); /* finish caller */ 1659 updatetrap(ci); /* 'luaD_poscall' can change hooks */ 1660 goto ret; /* caller returns after the tail call */ 1661 } 1662 ci->func -= delta; /* restore 'func' (if vararg) */ 1663 luaD_pretailcall(L, ci, ra, b); /* prepare call frame */ 1664 goto startfunc; /* execute the callee */ 1665 } 1666 vmcase(OP_RETURN) { 1667 int n = GETARG_B(i) - 1; /* number of results */ 1668 int nparams1 = GETARG_C(i); 1669 if (n < 0) /* not fixed? */ 1670 n = cast_int(L->top - ra); /* get what is available */ 1671 savepc(ci); 1672 if (TESTARG_k(i)) { /* may there be open upvalues? */ 1673 if (L->top < ci->top) 1674 L->top = ci->top; 1675 luaF_close(L, base, LUA_OK); 1676 updatetrap(ci); 1677 updatestack(ci); 1678 } 1679 if (nparams1) /* vararg function? */ 1680 ci->func -= ci->u.l.nextraargs + nparams1; 1681 L->top = ra + n; /* set call for 'luaD_poscall' */ 1682 luaD_poscall(L, ci, n); 1683 updatetrap(ci); /* 'luaD_poscall' can change hooks */ 1684 goto ret; 1685 } 1686 vmcase(OP_RETURN0) { 1687 if (L->hookmask) { 1688 L->top = ra; 1689 savepc(ci); 1690 luaD_poscall(L, ci, 0); /* no hurry... */ 1691 trap = 1; 1692 } 1693 else { /* do the 'poscall' here */ 1694 int nres = ci->nresults; 1695 L->ci = ci->previous; /* back to caller */ 1696 L->top = base - 1; 1697 while (nres-- > 0) 1698 setnilvalue(s2v(L->top++)); /* all results are nil */ 1699 } 1700 goto ret; 1701 } 1702 vmcase(OP_RETURN1) { 1703 if (L->hookmask) { 1704 L->top = ra + 1; 1705 savepc(ci); 1706 luaD_poscall(L, ci, 1); /* no hurry... */ 1707 trap = 1; 1708 } 1709 else { /* do the 'poscall' here */ 1710 int nres = ci->nresults; 1711 L->ci = ci->previous; /* back to caller */ 1712 if (nres == 0) 1713 L->top = base - 1; /* asked for no results */ 1714 else { 1715 setobjs2s(L, base - 1, ra); /* at least this result */ 1716 L->top = base; 1717 while (--nres > 0) /* complete missing results */ 1718 setnilvalue(s2v(L->top++)); 1719 } 1720 } 1721 ret: /* return from a Lua function */ 1722 if (ci->callstatus & CIST_FRESH) 1723 return; /* end this frame */ 1724 else { 1725 ci = ci->previous; 1726 goto returning; /* continue running caller in this frame */ 1727 } 1728 } 1729 vmcase(OP_FORLOOP) { 1730 if (ttisinteger(s2v(ra + 2))) { /* integer loop? */ 1731 lua_Unsigned count = l_castS2U(ivalue(s2v(ra + 1))); 1732 if (count > 0) { /* still more iterations? */ 1733 lua_Integer step = ivalue(s2v(ra + 2)); 1734 lua_Integer idx = ivalue(s2v(ra)); /* internal index */ 1735 chgivalue(s2v(ra + 1), count - 1); /* update counter */ 1736 idx = intop(+, idx, step); /* add step to index */ 1737 chgivalue(s2v(ra), idx); /* update internal index */ 1738 setivalue(s2v(ra + 3), idx); /* and control variable */ 1739 pc -= GETARG_Bx(i); /* jump back */ 1740 } 1741 } 1742 else if (floatforloop(ra)) /* float loop */ 1743 pc -= GETARG_Bx(i); /* jump back */ 1744 updatetrap(ci); /* allows a signal to break the loop */ 1745 vmbreak; 1746 } 1747 vmcase(OP_FORPREP) { 1748 savestate(L, ci); /* in case of errors */ 1749 if (forprep(L, ra)) 1750 pc += GETARG_Bx(i) + 1; /* skip the loop */ 1751 vmbreak; 1752 } 1753 vmcase(OP_TFORPREP) { 1754 /* create to-be-closed upvalue (if needed) */ 1755 halfProtect(luaF_newtbcupval(L, ra + 3)); 1756 pc += GETARG_Bx(i); 1757 i = *(pc++); /* go to next instruction */ 1758 lua_assert(GET_OPCODE(i) == OP_TFORCALL && ra == RA(i)); 1759 goto l_tforcall; 1760 } 1761 vmcase(OP_TFORCALL) { 1762 l_tforcall: 1763 /* 'ra' has the iterator function, 'ra + 1' has the state, 1764 'ra + 2' has the control variable, and 'ra + 3' has the 1765 to-be-closed variable. The call will use the stack after 1766 these values (starting at 'ra + 4') 1767 */ 1768 /* push function, state, and control variable */ 1769 memcpy(ra + 4, ra, 3 * sizeof(*ra)); 1770 L->top = ra + 4 + 3; 1771 ProtectNT(luaD_call(L, ra + 4, GETARG_C(i))); /* do the call */ 1772 updatestack(ci); /* stack may have changed */ 1773 i = *(pc++); /* go to next instruction */ 1774 lua_assert(GET_OPCODE(i) == OP_TFORLOOP && ra == RA(i)); 1775 goto l_tforloop; 1776 } 1777 vmcase(OP_TFORLOOP) { 1778 l_tforloop: 1779 if (!ttisnil(s2v(ra + 4))) { /* continue loop? */ 1780 setobjs2s(L, ra + 2, ra + 4); /* save control variable */ 1781 pc -= GETARG_Bx(i); /* jump back */ 1782 } 1783 vmbreak; 1784 } 1785 vmcase(OP_SETLIST) { 1786 int n = GETARG_B(i); 1787 unsigned int last = GETARG_C(i); 1788 Table *h = hvalue(s2v(ra)); 1789 if (n == 0) 1790 n = cast_int(L->top - ra) - 1; /* get up to the top */ 1791 else 1792 L->top = ci->top; /* correct top in case of emergency GC */ 1793 last += n; 1794 if (TESTARG_k(i)) { 1795 last += GETARG_Ax(*pc) * (MAXARG_C + 1); 1796 pc++; 1797 } 1798 if (last > luaH_realasize(h)) /* needs more space? */ 1799 luaH_resizearray(L, h, last); /* preallocate it at once */ 1800 for (; n > 0; n--) { 1801 TValue *val = s2v(ra + n); 1802 setobj2t(L, &h->array[last - 1], val); 1803 last--; 1804 luaC_barrierback(L, obj2gco(h), val); 1805 } 1806 vmbreak; 1807 } 1808 vmcase(OP_CLOSURE) { 1809 Proto *p = cl->p->p[GETARG_Bx(i)]; 1810 halfProtect(pushclosure(L, p, cl->upvals, base, ra)); 1811 checkGC(L, ra + 1); 1812 vmbreak; 1813 } 1814 vmcase(OP_VARARG) { 1815 int n = GETARG_C(i) - 1; /* required results */ 1816 Protect(luaT_getvarargs(L, ci, ra, n)); 1817 vmbreak; 1818 } 1819 vmcase(OP_VARARGPREP) { 1820 ProtectNT(luaT_adjustvarargs(L, GETARG_A(i), ci, cl->p)); 1821 if (trap) { 1822 luaD_hookcall(L, ci); 1823 L->oldpc = 1; /* next opcode will be seen as a "new" line */ 1824 } 1825 updatebase(ci); /* function has new base after adjustment */ 1826 vmbreak; 1827 } 1828 vmcase(OP_EXTRAARG) { 1829 lua_assert(0); 1830 vmbreak; 1831 } 1832 } 1833 } 1834 } 1835 1836 /* }================================================================== */ 1837