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author | Roberto Ierusalimschy <roberto@inf.puc-rio.br> | 2013-04-12 15:48:47 -0300 |
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committer | Roberto Ierusalimschy <roberto@inf.puc-rio.br> | 2013-04-12 15:48:47 -0300 |
commit | 2ca518141350667e38941eac35b76980095d2fdc (patch) | |
tree | 82595f0dfd57df5782905621298c8aae68b46389 /lvm.c | |
parent | f5ae26ec6c2eb69f03f316e59c1e1977c52c7c23 (diff) | |
download | lua-2ca518141350667e38941eac35b76980095d2fdc.tar.gz lua-2ca518141350667e38941eac35b76980095d2fdc.tar.bz2 lua-2ca518141350667e38941eac35b76980095d2fdc.zip |
Branch 5.2 - new releases for 5.2 go from here, main trunk goes
for next version
Diffstat (limited to 'lvm.c')
-rw-r--r-- | lvm.c | 867 |
1 files changed, 867 insertions, 0 deletions
@@ -0,0 +1,867 @@ | |||
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 | |||