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