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| 1 /* |
| 2 ** $Id: lvm.c,v 2.155 2013/03/16 21:10:18 roberto Exp $ |
| 3 ** Lua virtual machine |
| 4 ** See Copyright Notice in lua.h |
| 5 */ |
| 6 |
| 7 |
| 8 #include <stdio.h> |
| 9 #include <stdlib.h> |
| 10 #include <string.h> |
| 11 |
| 12 #define lvm_c |
| 13 #define LUA_CORE |
| 14 |
| 15 #include "lua.h" |
| 16 |
| 17 #include "ldebug.h" |
| 18 #include "ldo.h" |
| 19 #include "lfunc.h" |
| 20 #include "lgc.h" |
| 21 #include "lobject.h" |
| 22 #include "lopcodes.h" |
| 23 #include "lstate.h" |
| 24 #include "lstring.h" |
| 25 #include "ltable.h" |
| 26 #include "ltm.h" |
| 27 #include "lvm.h" |
| 28 |
| 29 |
| 30 |
| 31 /* limit for table tag-method chains (to avoid loops) */ |
| 32 #define MAXTAGLOOP 100 |
| 33 |
| 34 |
| 35 const TValue *luaV_tonumber (const TValue *obj, TValue *n) { |
| 36 lua_Number num; |
| 37 if (ttisnumber(obj)) return obj; |
| 38 if (ttisstring(obj) && luaO_str2d(svalue(obj), tsvalue(obj)->len, &num)) { |
| 39 setnvalue(n, num); |
| 40 return n; |
| 41 } |
| 42 else |
| 43 return NULL; |
| 44 } |
| 45 |
| 46 |
| 47 int luaV_tostring (lua_State *L, StkId obj) { |
| 48 if (!ttisnumber(obj)) |
| 49 return 0; |
| 50 else { |
| 51 char s[LUAI_MAXNUMBER2STR]; |
| 52 lua_Number n = nvalue(obj); |
| 53 int l = lua_number2str(s, n); |
| 54 setsvalue2s(L, obj, luaS_newlstr(L, s, l)); |
| 55 return 1; |
| 56 } |
| 57 } |
| 58 |
| 59 |
| 60 static void traceexec (lua_State *L) { |
| 61 CallInfo *ci = L->ci; |
| 62 lu_byte mask = L->hookmask; |
| 63 int counthook = ((mask & LUA_MASKCOUNT) && L->hookcount == 0); |
| 64 if (counthook) |
| 65 resethookcount(L); /* reset count */ |
| 66 if (ci->callstatus & CIST_HOOKYIELD) { /* called hook last time? */ |
| 67 ci->callstatus &= ~CIST_HOOKYIELD; /* erase mark */ |
| 68 return; /* do not call hook again (VM yielded, so it did not move) */ |
| 69 } |
| 70 if (counthook) |
| 71 luaD_hook(L, LUA_HOOKCOUNT, -1); /* call count hook */ |
| 72 if (mask & LUA_MASKLINE) { |
| 73 Proto *p = ci_func(ci)->p; |
| 74 int npc = pcRel(ci->u.l.savedpc, p); |
| 75 int newline = getfuncline(p, npc); |
| 76 if (npc == 0 || /* call linehook when enter a new function, */ |
| 77 ci->u.l.savedpc <= L->oldpc || /* when jump back (loop), or when */ |
| 78 newline != getfuncline(p, pcRel(L->oldpc, p))) /* enter a new line */ |
| 79 luaD_hook(L, LUA_HOOKLINE, newline); /* call line hook */ |
| 80 } |
| 81 L->oldpc = ci->u.l.savedpc; |
| 82 if (L->status == LUA_YIELD) { /* did hook yield? */ |
| 83 if (counthook) |
| 84 L->hookcount = 1; /* undo decrement to zero */ |
| 85 ci->u.l.savedpc--; /* undo increment (resume will increment it again) */ |
| 86 ci->callstatus |= CIST_HOOKYIELD; /* mark that it yielded */ |
| 87 ci->func = L->top - 1; /* protect stack below results */ |
| 88 luaD_throw(L, LUA_YIELD); |
| 89 } |
| 90 } |
| 91 |
| 92 |
| 93 static void callTM (lua_State *L, const TValue *f, const TValue *p1, |
| 94 const TValue *p2, TValue *p3, int hasres) { |
| 95 ptrdiff_t result = savestack(L, p3); |
| 96 setobj2s(L, L->top++, f); /* push function */ |
| 97 setobj2s(L, L->top++, p1); /* 1st argument */ |
| 98 setobj2s(L, L->top++, p2); /* 2nd argument */ |
| 99 if (!hasres) /* no result? 'p3' is third argument */ |
| 100 setobj2s(L, L->top++, p3); /* 3rd argument */ |
| 101 /* metamethod may yield only when called from Lua code */ |
| 102 luaD_call(L, L->top - (4 - hasres), hasres, isLua(L->ci)); |
| 103 if (hasres) { /* if has result, move it to its place */ |
| 104 p3 = restorestack(L, result); |
| 105 setobjs2s(L, p3, --L->top); |
| 106 } |
| 107 } |
| 108 |
| 109 |
| 110 void 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 not 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 callTM(L, tm, t, key, val, 1); |
| 128 return; |
| 129 } |
| 130 t = tm; /* else repeat with 'tm' */ |
| 131 } |
| 132 luaG_runerror(L, "loop in gettable"); |
| 133 } |
| 134 |
| 135 |
| 136 void 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 = cast(TValue *, luaH_get(h, key)); |
| 143 /* if previous value is not nil, there must be a previous entry |
| 144 in the table; moreover, a metamethod has no relevance */ |
| 145 if (!ttisnil(oldval) || |
| 146 /* previous value is nil; must check the metamethod */ |
| 147 ((tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL && |
| 148 /* no metamethod; is there a previous entry in the table? */ |
| 149 (oldval != luaO_nilobject || |
| 150 /* no previous entry; must create one. (The next test is |
| 151 always true; we only need the assignment.) */ |
| 152 (oldval = luaH_newkey(L, h, key), 1)))) { |
| 153 /* no metamethod and (now) there is an entry with given key */ |
| 154 setobj2t(L, oldval, val); /* assign new value to that entry */ |
| 155 invalidateTMcache(h); |
| 156 luaC_barrierback(L, obj2gco(h), val); |
| 157 return; |
| 158 } |
| 159 /* else will try the metamethod */ |
| 160 } |
| 161 else /* not a table; check metamethod */ |
| 162 if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX))) |
| 163 luaG_typeerror(L, t, "index"); |
| 164 /* there is a metamethod */ |
| 165 if (ttisfunction(tm)) { |
| 166 callTM(L, tm, t, key, val, 0); |
| 167 return; |
| 168 } |
| 169 t = tm; /* else repeat with 'tm' */ |
| 170 } |
| 171 luaG_runerror(L, "loop in settable"); |
| 172 } |
| 173 |
| 174 |
| 175 static int call_binTM (lua_State *L, const TValue *p1, const TValue *p2, |
| 176 StkId res, TMS event) { |
| 177 const TValue *tm = luaT_gettmbyobj(L, p1, event); /* try first operand */ |
| 178 if (ttisnil(tm)) |
| 179 tm = luaT_gettmbyobj(L, p2, event); /* try second operand */ |
| 180 if (ttisnil(tm)) return 0; |
| 181 callTM(L, tm, p1, p2, res, 1); |
| 182 return 1; |
| 183 } |
| 184 |
| 185 |
| 186 static const TValue *get_equalTM (lua_State *L, Table *mt1, Table *mt2, |
| 187 TMS event) { |
| 188 const TValue *tm1 = fasttm(L, mt1, event); |
| 189 const TValue *tm2; |
| 190 if (tm1 == NULL) return NULL; /* no metamethod */ |
| 191 if (mt1 == mt2) return tm1; /* same metatables => same metamethods */ |
| 192 tm2 = fasttm(L, mt2, event); |
| 193 if (tm2 == NULL) return NULL; /* no metamethod */ |
| 194 if (luaV_rawequalobj(tm1, tm2)) /* same metamethods? */ |
| 195 return tm1; |
| 196 return NULL; |
| 197 } |
| 198 |
| 199 |
| 200 static int call_orderTM (lua_State *L, const TValue *p1, const TValue *p2, |
| 201 TMS event) { |
| 202 if (!call_binTM(L, p1, p2, L->top, event)) |
| 203 return -1; /* no metamethod */ |
| 204 else |
| 205 return !l_isfalse(L->top); |
| 206 } |
| 207 |
| 208 |
| 209 static int l_strcmp (const TString *ls, const TString *rs) { |
| 210 const char *l = getstr(ls); |
| 211 size_t ll = ls->tsv.len; |
| 212 const char *r = getstr(rs); |
| 213 size_t lr = rs->tsv.len; |
| 214 for (;;) { |
| 215 int temp = strcoll(l, r); |
| 216 if (temp != 0) return temp; |
| 217 else { /* strings are equal up to a `\0' */ |
| 218 size_t len = strlen(l); /* index of first `\0' in both strings */ |
| 219 if (len == lr) /* r is finished? */ |
| 220 return (len == ll) ? 0 : 1; |
| 221 else if (len == ll) /* l is finished? */ |
| 222 return -1; /* l is smaller than r (because r is not finished) */ |
| 223 /* both strings longer than `len'; go on comparing (after the `\0') */ |
| 224 len++; |
| 225 l += len; ll -= len; r += len; lr -= len; |
| 226 } |
| 227 } |
| 228 } |
| 229 |
| 230 |
| 231 int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) { |
| 232 int res; |
| 233 if (ttisnumber(l) && ttisnumber(r)) |
| 234 return luai_numlt(L, nvalue(l), nvalue(r)); |
| 235 else if (ttisstring(l) && ttisstring(r)) |
| 236 return l_strcmp(rawtsvalue(l), rawtsvalue(r)) < 0; |
| 237 else if ((res = call_orderTM(L, l, r, TM_LT)) < 0) |
| 238 luaG_ordererror(L, l, r); |
| 239 return res; |
| 240 } |
| 241 |
| 242 |
| 243 int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r) { |
| 244 int res; |
| 245 if (ttisnumber(l) && ttisnumber(r)) |
| 246 return luai_numle(L, nvalue(l), nvalue(r)); |
| 247 else if (ttisstring(l) && ttisstring(r)) |
| 248 return l_strcmp(rawtsvalue(l), rawtsvalue(r)) <= 0; |
| 249 else if ((res = call_orderTM(L, l, r, TM_LE)) >= 0) /* first try `le' */ |
| 250 return res; |
| 251 else if ((res = call_orderTM(L, r, l, TM_LT)) < 0) /* else try `lt' */ |
| 252 luaG_ordererror(L, l, r); |
| 253 return !res; |
| 254 } |
| 255 |
| 256 |
| 257 /* |
| 258 ** equality of Lua values. L == NULL means raw equality (no metamethods) |
| 259 */ |
| 260 int luaV_equalobj_ (lua_State *L, const TValue *t1, const TValue *t2) { |
| 261 const TValue *tm; |
| 262 lua_assert(ttisequal(t1, t2)); |
| 263 switch (ttype(t1)) { |
| 264 case LUA_TNIL: return 1; |
| 265 case LUA_TNUMBER: return luai_numeq(nvalue(t1), nvalue(t2)); |
| 266 case LUA_TBOOLEAN: return bvalue(t1) == bvalue(t2); /* true must be 1 !! */ |
| 267 case LUA_TLIGHTUSERDATA: return pvalue(t1) == pvalue(t2); |
| 268 case LUA_TLCF: return fvalue(t1) == fvalue(t2); |
| 269 case LUA_TSHRSTR: return eqshrstr(rawtsvalue(t1), rawtsvalue(t2)); |
| 270 case LUA_TLNGSTR: return luaS_eqlngstr(rawtsvalue(t1), rawtsvalue(t2)); |
| 271 case LUA_TUSERDATA: { |
| 272 if (uvalue(t1) == uvalue(t2)) return 1; |
| 273 else if (L == NULL) return 0; |
| 274 tm = get_equalTM(L, uvalue(t1)->metatable, uvalue(t2)->metatable, TM_EQ); |
| 275 break; /* will try TM */ |
| 276 } |
| 277 case LUA_TTABLE: { |
| 278 if (hvalue(t1) == hvalue(t2)) return 1; |
| 279 else if (L == NULL) return 0; |
| 280 tm = get_equalTM(L, hvalue(t1)->metatable, hvalue(t2)->metatable, TM_EQ); |
| 281 break; /* will try TM */ |
| 282 } |
| 283 default: |
| 284 lua_assert(iscollectable(t1)); |
| 285 return gcvalue(t1) == gcvalue(t2); |
| 286 } |
| 287 if (tm == NULL) return 0; /* no TM? */ |
| 288 callTM(L, tm, t1, t2, L->top, 1); /* call TM */ |
| 289 return !l_isfalse(L->top); |
| 290 } |
| 291 |
| 292 |
| 293 void luaV_concat (lua_State *L, int total) { |
| 294 lua_assert(total >= 2); |
| 295 do { |
| 296 StkId top = L->top; |
| 297 int n = 2; /* number of elements handled in this pass (at least 2) */ |
| 298 if (!(ttisstring(top-2) || ttisnumber(top-2)) || !tostring(L, top-1)) { |
| 299 if (!call_binTM(L, top-2, top-1, top-2, TM_CONCAT)) |
| 300 luaG_concaterror(L, top-2, top-1); |
| 301 } |
| 302 else if (tsvalue(top-1)->len == 0) /* second operand is empty? */ |
| 303 (void)tostring(L, top - 2); /* result is first operand */ |
| 304 else if (ttisstring(top-2) && tsvalue(top-2)->len == 0) { |
| 305 setobjs2s(L, top - 2, top - 1); /* result is second op. */ |
| 306 } |
| 307 else { |
| 308 /* at least two non-empty string values; get as many as possible */ |
| 309 size_t tl = tsvalue(top-1)->len; |
| 310 char *buffer; |
| 311 int i; |
| 312 /* collect total length */ |
| 313 for (i = 1; i < total && tostring(L, top-i-1); i++) { |
| 314 size_t l = tsvalue(top-i-1)->len; |
| 315 if (l >= (MAX_SIZET/sizeof(char)) - tl) |
| 316 luaG_runerror(L, "string length overflow"); |
| 317 tl += l; |
| 318 } |
| 319 buffer = luaZ_openspace(L, &G(L)->buff, tl); |
| 320 tl = 0; |
| 321 n = i; |
| 322 do { /* concat all strings */ |
| 323 size_t l = tsvalue(top-i)->len; |
| 324 memcpy(buffer+tl, svalue(top-i), l * sizeof(char)); |
| 325 tl += l; |
| 326 } while (--i > 0); |
| 327 setsvalue2s(L, top-n, luaS_newlstr(L, buffer, tl)); |
| 328 } |
| 329 total -= n-1; /* got 'n' strings to create 1 new */ |
| 330 L->top -= n-1; /* popped 'n' strings and pushed one */ |
| 331 } while (total > 1); /* repeat until only 1 result left */ |
| 332 } |
| 333 |
| 334 |
| 335 void luaV_objlen (lua_State *L, StkId ra, const TValue *rb) { |
| 336 const TValue *tm; |
| 337 switch (ttypenv(rb)) { |
| 338 case LUA_TTABLE: { |
| 339 Table *h = hvalue(rb); |
| 340 tm = fasttm(L, h->metatable, TM_LEN); |
| 341 if (tm) break; /* metamethod? break switch to call it */ |
| 342 setnvalue(ra, cast_num(luaH_getn(h))); /* else primitive len */ |
| 343 return; |
| 344 } |
| 345 case LUA_TSTRING: { |
| 346 setnvalue(ra, cast_num(tsvalue(rb)->len)); |
| 347 return; |
| 348 } |
| 349 default: { /* try metamethod */ |
| 350 tm = luaT_gettmbyobj(L, rb, TM_LEN); |
| 351 if (ttisnil(tm)) /* no metamethod? */ |
| 352 luaG_typeerror(L, rb, "get length of"); |
| 353 break; |
| 354 } |
| 355 } |
| 356 callTM(L, tm, rb, rb, ra, 1); |
| 357 } |
| 358 |
| 359 |
| 360 void luaV_arith (lua_State *L, StkId ra, const TValue *rb, |
| 361 const TValue *rc, TMS op) { |
| 362 TValue tempb, tempc; |
| 363 const TValue *b, *c; |
| 364 if ((b = luaV_tonumber(rb, &tempb)) != NULL && |
| 365 (c = luaV_tonumber(rc, &tempc)) != NULL) { |
| 366 lua_Number res = luaO_arith(op - TM_ADD + LUA_OPADD, nvalue(b), nvalue(c)); |
| 367 setnvalue(ra, res); |
| 368 } |
| 369 else if (!call_binTM(L, rb, rc, ra, op)) |
| 370 luaG_aritherror(L, rb, rc); |
| 371 } |
| 372 |
| 373 |
| 374 /* |
| 375 ** check whether cached closure in prototype 'p' may be reused, that is, |
| 376 ** whether there is a cached closure with the same upvalues needed by |
| 377 ** new closure to be created. |
| 378 */ |
| 379 static Closure *getcached (Proto *p, UpVal **encup, StkId base) { |
| 380 Closure *c = p->cache; |
| 381 if (c != NULL) { /* is there a cached closure? */ |
| 382 int nup = p->sizeupvalues; |
| 383 Upvaldesc *uv = p->upvalues; |
| 384 int i; |
| 385 for (i = 0; i < nup; i++) { /* check whether it has right upvalues */ |
| 386 TValue *v = uv[i].instack ? base + uv[i].idx : encup[uv[i].idx]->v; |
| 387 if (c->l.upvals[i]->v != v) |
| 388 return NULL; /* wrong upvalue; cannot reuse closure */ |
| 389 } |
| 390 } |
| 391 return c; /* return cached closure (or NULL if no cached closure) */ |
| 392 } |
| 393 |
| 394 |
| 395 /* |
| 396 ** create a new Lua closure, push it in the stack, and initialize |
| 397 ** its upvalues. Note that the call to 'luaC_barrierproto' must come |
| 398 ** before the assignment to 'p->cache', as the function needs the |
| 399 ** original value of that field. |
| 400 */ |
| 401 static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base, |
| 402 StkId ra) { |
| 403 int nup = p->sizeupvalues; |
| 404 Upvaldesc *uv = p->upvalues; |
| 405 int i; |
| 406 Closure *ncl = luaF_newLclosure(L, nup); |
| 407 ncl->l.p = p; |
| 408 setclLvalue(L, ra, ncl); /* anchor new closure in stack */ |
| 409 for (i = 0; i < nup; i++) { /* fill in its upvalues */ |
| 410 if (uv[i].instack) /* upvalue refers to local variable? */ |
| 411 ncl->l.upvals[i] = luaF_findupval(L, base + uv[i].idx); |
| 412 else /* get upvalue from enclosing function */ |
| 413 ncl->l.upvals[i] = encup[uv[i].idx]; |
| 414 } |
| 415 luaC_barrierproto(L, p, ncl); |
| 416 p->cache = ncl; /* save it on cache for reuse */ |
| 417 } |
| 418 |
| 419 |
| 420 /* |
| 421 ** finish execution of an opcode interrupted by an yield |
| 422 */ |
| 423 void luaV_finishOp (lua_State *L) { |
| 424 CallInfo *ci = L->ci; |
| 425 StkId base = ci->u.l.base; |
| 426 Instruction inst = *(ci->u.l.savedpc - 1); /* interrupted instruction */ |
| 427 OpCode op = GET_OPCODE(inst); |
| 428 switch (op) { /* finish its execution */ |
| 429 case OP_ADD: case OP_SUB: case OP_MUL: case OP_DIV: |
| 430 case OP_MOD: case OP_POW: case OP_UNM: case OP_LEN: |
| 431 case OP_GETTABUP: case OP_GETTABLE: case OP_SELF: { |
| 432 setobjs2s(L, base + GETARG_A(inst), --L->top); |
| 433 break; |
| 434 } |
| 435 case OP_LE: case OP_LT: case OP_EQ: { |
| 436 int res = !l_isfalse(L->top - 1); |
| 437 L->top--; |
| 438 /* metamethod should not be called when operand is K */ |
| 439 lua_assert(!ISK(GETARG_B(inst))); |
| 440 if (op == OP_LE && /* "<=" using "<" instead? */ |
| 441 ttisnil(luaT_gettmbyobj(L, base + GETARG_B(inst), TM_LE))) |
| 442 res = !res; /* invert result */ |
| 443 lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_JMP); |
| 444 if (res != GETARG_A(inst)) /* condition failed? */ |
| 445 ci->u.l.savedpc++; /* skip jump instruction */ |
| 446 break; |
| 447 } |
| 448 case OP_CONCAT: { |
| 449 StkId top = L->top - 1; /* top when 'call_binTM' was called */ |
| 450 int b = GETARG_B(inst); /* first element to concatenate */ |
| 451 int total = cast_int(top - 1 - (base + b)); /* yet to concatenate */ |
| 452 setobj2s(L, top - 2, top); /* put TM result in proper position */ |
| 453 if (total > 1) { /* are there elements to concat? */ |
| 454 L->top = top - 1; /* top is one after last element (at top-2) */ |
| 455 luaV_concat(L, total); /* concat them (may yield again) */ |
| 456 } |
| 457 /* move final result to final position */ |
| 458 setobj2s(L, ci->u.l.base + GETARG_A(inst), L->top - 1); |
| 459 L->top = ci->top; /* restore top */ |
| 460 break; |
| 461 } |
| 462 case OP_TFORCALL: { |
| 463 lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_TFORLOOP); |
| 464 L->top = ci->top; /* correct top */ |
| 465 break; |
| 466 } |
| 467 case OP_CALL: { |
| 468 if (GETARG_C(inst) - 1 >= 0) /* nresults >= 0? */ |
| 469 L->top = ci->top; /* adjust results */ |
| 470 break; |
| 471 } |
| 472 case OP_TAILCALL: case OP_SETTABUP: case OP_SETTABLE: |
| 473 break; |
| 474 default: lua_assert(0); |
| 475 } |
| 476 } |
| 477 |
| 478 |
| 479 |
| 480 /* |
| 481 ** some macros for common tasks in `luaV_execute' |
| 482 */ |
| 483 |
| 484 #if !defined luai_runtimecheck |
| 485 #define luai_runtimecheck(L, c) /* void */ |
| 486 #endif |
| 487 |
| 488 |
| 489 #define RA(i) (base+GETARG_A(i)) |
| 490 /* to be used after possible stack reallocation */ |
| 491 #define RB(i) check_exp(getBMode(GET_OPCODE(i)) == OpArgR, base+GETARG_B(i)) |
| 492 #define RC(i) check_exp(getCMode(GET_OPCODE(i)) == OpArgR, base+GETARG_C(i)) |
| 493 #define RKB(i) check_exp(getBMode(GET_OPCODE(i)) == OpArgK, \ |
| 494 ISK(GETARG_B(i)) ? k+INDEXK(GETARG_B(i)) : base+GETARG_B(i)) |
| 495 #define RKC(i) check_exp(getCMode(GET_OPCODE(i)) == OpArgK, \ |
| 496 ISK(GETARG_C(i)) ? k+INDEXK(GETARG_C(i)) : base+GETARG_C(i)) |
| 497 #define KBx(i) \ |
| 498 (k + (GETARG_Bx(i) != 0 ? GETARG_Bx(i) - 1 : GETARG_Ax(*ci->u.l.savedpc++))) |
| 499 |
| 500 |
| 501 /* execute a jump instruction */ |
| 502 #define dojump(ci,i,e) \ |
| 503 { int a = GETARG_A(i); \ |
| 504 if (a > 0) luaF_close(L, ci->u.l.base + a - 1); \ |
| 505 ci->u.l.savedpc += GETARG_sBx(i) + e; } |
| 506 |
| 507 /* for test instructions, execute the jump instruction that follows it */ |
| 508 #define donextjump(ci) { i = *ci->u.l.savedpc; dojump(ci, i, 1); } |
| 509 |
| 510 |
| 511 #define Protect(x) { {x;}; base = ci->u.l.base; } |
| 512 |
| 513 #define checkGC(L,c) \ |
| 514 Protect( luaC_condGC(L,{L->top = (c); /* limit of live values */ \ |
| 515 luaC_step(L); \ |
| 516 L->top = ci->top;}) /* restore top */ \ |
| 517 luai_threadyield(L); ) |
| 518 |
| 519 |
| 520 #define arith_op(op,tm) { \ |
| 521 TValue *rb = RKB(i); \ |
| 522 TValue *rc = RKC(i); \ |
| 523 if (ttisnumber(rb) && ttisnumber(rc)) { \ |
| 524 lua_Number nb = nvalue(rb), nc = nvalue(rc); \ |
| 525 setnvalue(ra, op(L, nb, nc)); \ |
| 526 } \ |
| 527 else { Protect(luaV_arith(L, ra, rb, rc, tm)); } } |
| 528 |
| 529 |
| 530 #define vmdispatch(o) switch(o) |
| 531 #define vmcase(l,b) case l: {b} break; |
| 532 #define vmcasenb(l,b) case l: {b} /* nb = no break */ |
| 533 |
| 534 void luaV_execute (lua_State *L) { |
| 535 CallInfo *ci = L->ci; |
| 536 LClosure *cl; |
| 537 TValue *k; |
| 538 StkId base; |
| 539 newframe: /* reentry point when frame changes (call/return) */ |
| 540 lua_assert(ci == L->ci); |
| 541 cl = clLvalue(ci->func); |
| 542 k = cl->p->k; |
| 543 base = ci->u.l.base; |
| 544 /* main loop of interpreter */ |
| 545 for (;;) { |
| 546 Instruction i = *(ci->u.l.savedpc++); |
| 547 StkId ra; |
| 548 if ((L->hookmask & (LUA_MASKLINE | LUA_MASKCOUNT)) && |
| 549 (--L->hookcount == 0 || L->hookmask & LUA_MASKLINE)) { |
| 550 Protect(traceexec(L)); |
| 551 } |
| 552 /* WARNING: several calls may realloc the stack and invalidate `ra' */ |
| 553 ra = RA(i); |
| 554 lua_assert(base == ci->u.l.base); |
| 555 lua_assert(base <= L->top && L->top < L->stack + L->stacksize); |
| 556 vmdispatch (GET_OPCODE(i)) { |
| 557 vmcase(OP_MOVE, |
| 558 setobjs2s(L, ra, RB(i)); |
| 559 ) |
| 560 vmcase(OP_LOADK, |
| 561 TValue *rb = k + GETARG_Bx(i); |
| 562 setobj2s(L, ra, rb); |
| 563 ) |
| 564 vmcase(OP_LOADKX, |
| 565 TValue *rb; |
| 566 lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_EXTRAARG); |
| 567 rb = k + GETARG_Ax(*ci->u.l.savedpc++); |
| 568 setobj2s(L, ra, rb); |
| 569 ) |
| 570 vmcase(OP_LOADBOOL, |
| 571 setbvalue(ra, GETARG_B(i)); |
| 572 if (GETARG_C(i)) ci->u.l.savedpc++; /* skip next instruction (if C) */ |
| 573 ) |
| 574 vmcase(OP_LOADNIL, |
| 575 int b = GETARG_B(i); |
| 576 do { |
| 577 setnilvalue(ra++); |
| 578 } while (b--); |
| 579 ) |
| 580 vmcase(OP_GETUPVAL, |
| 581 int b = GETARG_B(i); |
| 582 setobj2s(L, ra, cl->upvals[b]->v); |
| 583 ) |
| 584 vmcase(OP_GETTABUP, |
| 585 int b = GETARG_B(i); |
| 586 Protect(luaV_gettable(L, cl->upvals[b]->v, RKC(i), ra)); |
| 587 ) |
| 588 vmcase(OP_GETTABLE, |
| 589 Protect(luaV_gettable(L, RB(i), RKC(i), ra)); |
| 590 ) |
| 591 vmcase(OP_SETTABUP, |
| 592 int a = GETARG_A(i); |
| 593 Protect(luaV_settable(L, cl->upvals[a]->v, RKB(i), RKC(i))); |
| 594 ) |
| 595 vmcase(OP_SETUPVAL, |
| 596 UpVal *uv = cl->upvals[GETARG_B(i)]; |
| 597 setobj(L, uv->v, ra); |
| 598 luaC_barrier(L, uv, ra); |
| 599 ) |
| 600 vmcase(OP_SETTABLE, |
| 601 Protect(luaV_settable(L, ra, RKB(i), RKC(i))); |
| 602 ) |
| 603 vmcase(OP_NEWTABLE, |
| 604 int b = GETARG_B(i); |
| 605 int c = GETARG_C(i); |
| 606 Table *t = luaH_new(L); |
| 607 sethvalue(L, ra, t); |
| 608 if (b != 0 || c != 0) |
| 609 luaH_resize(L, t, luaO_fb2int(b), luaO_fb2int(c)); |
| 610 checkGC(L, ra + 1); |
| 611 ) |
| 612 vmcase(OP_SELF, |
| 613 StkId rb = RB(i); |
| 614 setobjs2s(L, ra+1, rb); |
| 615 Protect(luaV_gettable(L, rb, RKC(i), ra)); |
| 616 ) |
| 617 vmcase(OP_ADD, |
| 618 arith_op(luai_numadd, TM_ADD); |
| 619 ) |
| 620 vmcase(OP_SUB, |
| 621 arith_op(luai_numsub, TM_SUB); |
| 622 ) |
| 623 vmcase(OP_MUL, |
| 624 arith_op(luai_nummul, TM_MUL); |
| 625 ) |
| 626 vmcase(OP_DIV, |
| 627 arith_op(luai_numdiv, TM_DIV); |
| 628 ) |
| 629 vmcase(OP_MOD, |
| 630 arith_op(luai_nummod, TM_MOD); |
| 631 ) |
| 632 vmcase(OP_POW, |
| 633 arith_op(luai_numpow, TM_POW); |
| 634 ) |
| 635 vmcase(OP_UNM, |
| 636 TValue *rb = RB(i); |
| 637 if (ttisnumber(rb)) { |
| 638 lua_Number nb = nvalue(rb); |
| 639 setnvalue(ra, luai_numunm(L, nb)); |
| 640 } |
| 641 else { |
| 642 Protect(luaV_arith(L, ra, rb, rb, TM_UNM)); |
| 643 } |
| 644 ) |
| 645 vmcase(OP_NOT, |
| 646 TValue *rb = RB(i); |
| 647 int res = l_isfalse(rb); /* next assignment may change this value */ |
| 648 setbvalue(ra, res); |
| 649 ) |
| 650 vmcase(OP_LEN, |
| 651 Protect(luaV_objlen(L, ra, RB(i))); |
| 652 ) |
| 653 vmcase(OP_CONCAT, |
| 654 int b = GETARG_B(i); |
| 655 int c = GETARG_C(i); |
| 656 StkId rb; |
| 657 L->top = base + c + 1; /* mark the end of concat operands */ |
| 658 Protect(luaV_concat(L, c - b + 1)); |
| 659 ra = RA(i); /* 'luav_concat' may invoke TMs and move the stack */ |
| 660 rb = b + base; |
| 661 setobjs2s(L, ra, rb); |
| 662 checkGC(L, (ra >= rb ? ra + 1 : rb)); |
| 663 L->top = ci->top; /* restore top */ |
| 664 ) |
| 665 vmcase(OP_JMP, |
| 666 dojump(ci, i, 0); |
| 667 ) |
| 668 vmcase(OP_EQ, |
| 669 TValue *rb = RKB(i); |
| 670 TValue *rc = RKC(i); |
| 671 Protect( |
| 672 if (cast_int(equalobj(L, rb, rc)) != GETARG_A(i)) |
| 673 ci->u.l.savedpc++; |
| 674 else |
| 675 donextjump(ci); |
| 676 ) |
| 677 ) |
| 678 vmcase(OP_LT, |
| 679 Protect( |
| 680 if (luaV_lessthan(L, RKB(i), RKC(i)) != GETARG_A(i)) |
| 681 ci->u.l.savedpc++; |
| 682 else |
| 683 donextjump(ci); |
| 684 ) |
| 685 ) |
| 686 vmcase(OP_LE, |
| 687 Protect( |
| 688 if (luaV_lessequal(L, RKB(i), RKC(i)) != GETARG_A(i)) |
| 689 ci->u.l.savedpc++; |
| 690 else |
| 691 donextjump(ci); |
| 692 ) |
| 693 ) |
| 694 vmcase(OP_TEST, |
| 695 if (GETARG_C(i) ? l_isfalse(ra) : !l_isfalse(ra)) |
| 696 ci->u.l.savedpc++; |
| 697 else |
| 698 donextjump(ci); |
| 699 ) |
| 700 vmcase(OP_TESTSET, |
| 701 TValue *rb = RB(i); |
| 702 if (GETARG_C(i) ? l_isfalse(rb) : !l_isfalse(rb)) |
| 703 ci->u.l.savedpc++; |
| 704 else { |
| 705 setobjs2s(L, ra, rb); |
| 706 donextjump(ci); |
| 707 } |
| 708 ) |
| 709 vmcase(OP_CALL, |
| 710 int b = GETARG_B(i); |
| 711 int nresults = GETARG_C(i) - 1; |
| 712 if (b != 0) L->top = ra+b; /* else previous instruction set top */ |
| 713 if (luaD_precall(L, ra, nresults)) { /* C function? */ |
| 714 if (nresults >= 0) L->top = ci->top; /* adjust results */ |
| 715 base = ci->u.l.base; |
| 716 } |
| 717 else { /* Lua function */ |
| 718 ci = L->ci; |
| 719 ci->callstatus |= CIST_REENTRY; |
| 720 goto newframe; /* restart luaV_execute over new Lua function */ |
| 721 } |
| 722 ) |
| 723 vmcase(OP_TAILCALL, |
| 724 int b = GETARG_B(i); |
| 725 if (b != 0) L->top = ra+b; /* else previous instruction set top */ |
| 726 lua_assert(GETARG_C(i) - 1 == LUA_MULTRET); |
| 727 if (luaD_precall(L, ra, LUA_MULTRET)) /* C function? */ |
| 728 base = ci->u.l.base; |
| 729 else { |
| 730 /* tail call: put called frame (n) in place of caller one (o) */ |
| 731 CallInfo *nci = L->ci; /* called frame */ |
| 732 CallInfo *oci = nci->previous; /* caller frame */ |
| 733 StkId nfunc = nci->func; /* called function */ |
| 734 StkId ofunc = oci->func; /* caller function */ |
| 735 /* last stack slot filled by 'precall' */ |
| 736 StkId lim = nci->u.l.base + getproto(nfunc)->numparams; |
| 737 int aux; |
| 738 /* close all upvalues from previous call */ |
| 739 if (cl->p->sizep > 0) luaF_close(L, oci->u.l.base); |
| 740 /* move new frame into old one */ |
| 741 for (aux = 0; nfunc + aux < lim; aux++) |
| 742 setobjs2s(L, ofunc + aux, nfunc + aux); |
| 743 oci->u.l.base = ofunc + (nci->u.l.base - nfunc); /* correct base */ |
| 744 oci->top = L->top = ofunc + (L->top - nfunc); /* correct top */ |
| 745 oci->u.l.savedpc = nci->u.l.savedpc; |
| 746 oci->callstatus |= CIST_TAIL; /* function was tail called */ |
| 747 ci = L->ci = oci; /* remove new frame */ |
| 748 lua_assert(L->top == oci->u.l.base + getproto(ofunc)->maxstacksize); |
| 749 goto newframe; /* restart luaV_execute over new Lua function */ |
| 750 } |
| 751 ) |
| 752 vmcasenb(OP_RETURN, |
| 753 int b = GETARG_B(i); |
| 754 if (b != 0) L->top = ra+b-1; |
| 755 if (cl->p->sizep > 0) luaF_close(L, base); |
| 756 b = luaD_poscall(L, ra); |
| 757 if (!(ci->callstatus & CIST_REENTRY)) /* 'ci' still the called one */ |
| 758 return; /* external invocation: return */ |
| 759 else { /* invocation via reentry: continue execution */ |
| 760 ci = L->ci; |
| 761 if (b) L->top = ci->top; |
| 762 lua_assert(isLua(ci)); |
| 763 lua_assert(GET_OPCODE(*((ci)->u.l.savedpc - 1)) == OP_CALL); |
| 764 goto newframe; /* restart luaV_execute over new Lua function */ |
| 765 } |
| 766 ) |
| 767 vmcase(OP_FORLOOP, |
| 768 lua_Number step = nvalue(ra+2); |
| 769 lua_Number idx = luai_numadd(L, nvalue(ra), step); /* increment index */ |
| 770 lua_Number limit = nvalue(ra+1); |
| 771 if (luai_numlt(L, 0, step) ? luai_numle(L, idx, limit) |
| 772 : luai_numle(L, limit, idx)) { |
| 773 ci->u.l.savedpc += GETARG_sBx(i); /* jump back */ |
| 774 setnvalue(ra, idx); /* update internal index... */ |
| 775 setnvalue(ra+3, idx); /* ...and external index */ |
| 776 } |
| 777 ) |
| 778 vmcase(OP_FORPREP, |
| 779 const TValue *init = ra; |
| 780 const TValue *plimit = ra+1; |
| 781 const TValue *pstep = ra+2; |
| 782 if (!tonumber(init, ra)) |
| 783 luaG_runerror(L, LUA_QL("for") " initial value must be a number"); |
| 784 else if (!tonumber(plimit, ra+1)) |
| 785 luaG_runerror(L, LUA_QL("for") " limit must be a number"); |
| 786 else if (!tonumber(pstep, ra+2)) |
| 787 luaG_runerror(L, LUA_QL("for") " step must be a number"); |
| 788 setnvalue(ra, luai_numsub(L, nvalue(ra), nvalue(pstep))); |
| 789 ci->u.l.savedpc += GETARG_sBx(i); |
| 790 ) |
| 791 vmcasenb(OP_TFORCALL, |
| 792 StkId cb = ra + 3; /* call base */ |
| 793 setobjs2s(L, cb+2, ra+2); |
| 794 setobjs2s(L, cb+1, ra+1); |
| 795 setobjs2s(L, cb, ra); |
| 796 L->top = cb + 3; /* func. + 2 args (state and index) */ |
| 797 Protect(luaD_call(L, cb, GETARG_C(i), 1)); |
| 798 L->top = ci->top; |
| 799 i = *(ci->u.l.savedpc++); /* go to next instruction */ |
| 800 ra = RA(i); |
| 801 lua_assert(GET_OPCODE(i) == OP_TFORLOOP); |
| 802 goto l_tforloop; |
| 803 ) |
| 804 vmcase(OP_TFORLOOP, |
| 805 l_tforloop: |
| 806 if (!ttisnil(ra + 1)) { /* continue loop? */ |
| 807 setobjs2s(L, ra, ra + 1); /* save control variable */ |
| 808 ci->u.l.savedpc += GETARG_sBx(i); /* jump back */ |
| 809 } |
| 810 ) |
| 811 vmcase(OP_SETLIST, |
| 812 int n = GETARG_B(i); |
| 813 int c = GETARG_C(i); |
| 814 int last; |
| 815 Table *h; |
| 816 if (n == 0) n = cast_int(L->top - ra) - 1; |
| 817 if (c == 0) { |
| 818 lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_EXTRAARG); |
| 819 c = GETARG_Ax(*ci->u.l.savedpc++); |
| 820 } |
| 821 luai_runtimecheck(L, ttistable(ra)); |
| 822 h = hvalue(ra); |
| 823 last = ((c-1)*LFIELDS_PER_FLUSH) + n; |
| 824 if (last > h->sizearray) /* needs more space? */ |
| 825 luaH_resizearray(L, h, last); /* pre-allocate it at once */ |
| 826 for (; n > 0; n--) { |
| 827 TValue *val = ra+n; |
| 828 luaH_setint(L, h, last--, val); |
| 829 luaC_barrierback(L, obj2gco(h), val); |
| 830 } |
| 831 L->top = ci->top; /* correct top (in case of previous open call) */ |
| 832 ) |
| 833 vmcase(OP_CLOSURE, |
| 834 Proto *p = cl->p->p[GETARG_Bx(i)]; |
| 835 Closure *ncl = getcached(p, cl->upvals, base); /* cached closure */ |
| 836 if (ncl == NULL) /* no match? */ |
| 837 pushclosure(L, p, cl->upvals, base, ra); /* create a new one */ |
| 838 else |
| 839 setclLvalue(L, ra, ncl); /* push cashed closure */ |
| 840 checkGC(L, ra + 1); |
| 841 ) |
| 842 vmcase(OP_VARARG, |
| 843 int b = GETARG_B(i) - 1; |
| 844 int j; |
| 845 int n = cast_int(base - ci->func) - cl->p->numparams - 1; |
| 846 if (b < 0) { /* B == 0? */ |
| 847 b = n; /* get all var. arguments */ |
| 848 Protect(luaD_checkstack(L, n)); |
| 849 ra = RA(i); /* previous call may change the stack */ |
| 850 L->top = ra + n; |
| 851 } |
| 852 for (j = 0; j < b; j++) { |
| 853 if (j < n) { |
| 854 setobjs2s(L, ra + j, base - n + j); |
| 855 } |
| 856 else { |
| 857 setnilvalue(ra + j); |
| 858 } |
| 859 } |
| 860 ) |
| 861 vmcase(OP_EXTRAARG, |
| 862 lua_assert(0); |
| 863 ) |
| 864 } |
| 865 } |
| 866 } |
| 867 |
OLD | NEW |