1 /* $NetBSD: lvm.c,v 1.20 2023/06/08 21:12:08 nikita Exp $ */
2
3 /*
4 ** Id: lvm.c
5 ** Lua virtual machine
6 ** See Copyright Notice in lua.h
7 */
8
9 #define lvm_c
10 #define LUA_CORE
11
12 #include "lprefix.h"
13
14 #ifndef _KERNEL
15 #include <float.h>
16 #include <limits.h>
17 #include <math.h>
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <string.h>
21 #endif /* _KERNEL */
22
23 #include "lua.h"
24
25 #include "ldebug.h"
26 #include "ldo.h"
27 #include "lfunc.h"
28 #include "lgc.h"
29 #include "lobject.h"
30 #include "lopcodes.h"
31 #include "lstate.h"
32 #include "lstring.h"
33 #include "ltable.h"
34 #include "ltm.h"
35 #include "lvm.h"
36
37
38 /*
39 ** By default, use jump tables in the main interpreter loop on gcc
40 ** and compatible compilers.
41 */
42 #if !defined(LUA_USE_JUMPTABLE)
43 #if defined(__GNUC__)
44 #define LUA_USE_JUMPTABLE 1
45 #else
46 #define LUA_USE_JUMPTABLE 0
47 #endif
48 #endif
49
50
51
52 /* limit for table tag-method chains (to avoid infinite loops) */
53 #define MAXTAGLOOP 2000
54
55
56 #ifndef _KERNEL
57 /*
58 ** 'l_intfitsf' checks whether a given integer is in the range that
59 ** can be converted to a float without rounding. Used in comparisons.
60 */
61
62 /* number of bits in the mantissa of a float */
63 #define NBM (l_floatatt(MANT_DIG))
64
65 /*
66 ** Check whether some integers may not fit in a float, testing whether
67 ** (maxinteger >> NBM) > 0. (That implies (1 << NBM) <= maxinteger.)
68 ** (The shifts are done in parts, to avoid shifting by more than the size
69 ** of an integer. In a worst case, NBM == 113 for long double and
70 ** sizeof(long) == 32.)
71 */
72 #if ((((LUA_MAXINTEGER >> (NBM / 4)) >> (NBM / 4)) >> (NBM / 4)) \
73 >> (NBM - (3 * (NBM / 4)))) > 0
74
75 /* limit for integers that fit in a float */
76 #define MAXINTFITSF ((lua_Unsigned)1 << NBM)
77
78 /* check whether 'i' is in the interval [-MAXINTFITSF, MAXINTFITSF] */
79 #define l_intfitsf(i) ((MAXINTFITSF + l_castS2U(i)) <= (2 * MAXINTFITSF))
80
81 #else /* all integers fit in a float precisely */
82
83 #define l_intfitsf(i) 1
84
85 #endif
86
87 #endif /* _KERNEL */
88
89
90
91 /*
92 ** Try to convert a value from string to a number value.
93 ** If the value is not a string or is a string not representing
94 ** a valid numeral (or if coercions from strings to numbers
95 ** are disabled via macro 'cvt2num'), do not modify 'result'
96 ** and return 0.
97 */
l_strton(const TValue * obj,TValue * result)98 static int l_strton (const TValue *obj, TValue *result) {
99 lua_assert(obj != result);
100 if (!cvt2num(obj)) /* is object not a string? */
101 return 0;
102 else
103 return (luaO_str2num(svalue(obj), result) == vslen(obj) + 1);
104 }
105
106
107 #ifndef _KERNEL
108 /*
109 ** Try to convert a value to a float. The float case is already handled
110 ** by the macro 'tonumber'.
111 */
luaV_tonumber_(const TValue * obj,lua_Number * n)112 int luaV_tonumber_ (const TValue *obj, lua_Number *n) {
113 TValue v;
114 if (ttisinteger(obj)) {
115 *n = cast_num(ivalue(obj));
116 return 1;
117 }
118 else if (l_strton(obj, &v)) { /* string coercible to number? */
119 *n = nvalue(&v); /* convert result of 'luaO_str2num' to a float */
120 return 1;
121 }
122 else
123 return 0; /* conversion failed */
124 }
125
126
127 /*
128 ** try to convert a float to an integer, rounding according to 'mode'.
129 */
luaV_flttointeger(lua_Number n,lua_Integer * p,F2Imod mode)130 int luaV_flttointeger (lua_Number n, lua_Integer *p, F2Imod mode) {
131 lua_Number f = l_floor(n);
132 if (n != f) { /* not an integral value? */
133 if (mode == F2Ieq) return 0; /* fails if mode demands integral value */
134 else if (mode == F2Iceil) /* needs ceil? */
135 f += 1; /* convert floor to ceil (remember: n != f) */
136 }
137 return lua_numbertointeger(f, p);
138 }
139 #endif /* _KERNEL */
140
141
142 /*
143 ** try to convert a value to an integer, rounding according to 'mode',
144 ** without string coercion.
145 ** ("Fast track" handled by macro 'tointegerns'.)
146 */
luaV_tointegerns(const TValue * obj,lua_Integer * p,F2Imod mode)147 int luaV_tointegerns (const TValue *obj, lua_Integer *p, F2Imod mode) {
148 #ifndef _KERNEL
149 if (ttisfloat(obj))
150 return luaV_flttointeger(fltvalue(obj), p, mode);
151 else if (ttisinteger(obj)) {
152 #else /* _KERNEL */
153 if (ttisinteger(obj)) {
154 UNUSED(mode);
155 #endif /* _KERNEL */
156 *p = ivalue(obj);
157 return 1;
158 }
159 else
160 return 0;
161 }
162
163
164 /*
165 ** try to convert a value to an integer.
166 */
167 int luaV_tointeger (const TValue *obj, lua_Integer *p, F2Imod mode) {
168 TValue v;
169 if (l_strton(obj, &v)) /* does 'obj' point to a numerical string? */
170 obj = &v; /* change it to point to its corresponding number */
171 return luaV_tointegerns(obj, p, mode);
172 }
173
174
175 #ifndef _KERNEL
176 /*
177 ** Try to convert a 'for' limit to an integer, preserving the semantics
178 ** of the loop. Return true if the loop must not run; otherwise, '*p'
179 ** gets the integer limit.
180 ** (The following explanation assumes a positive step; it is valid for
181 ** negative steps mutatis mutandis.)
182 ** If the limit is an integer or can be converted to an integer,
183 ** rounding down, that is the limit.
184 ** Otherwise, check whether the limit can be converted to a float. If
185 ** the float is too large, clip it to LUA_MAXINTEGER. If the float
186 ** is too negative, the loop should not run, because any initial
187 ** integer value is greater than such limit; so, the function returns
188 ** true to signal that. (For this latter case, no integer limit would be
189 ** correct; even a limit of LUA_MININTEGER would run the loop once for
190 ** an initial value equal to LUA_MININTEGER.)
191 */
192 static int forlimit (lua_State *L, lua_Integer init, const TValue *lim,
193 lua_Integer *p, lua_Integer step) {
194 if (!luaV_tointeger(lim, p, (step < 0 ? F2Iceil : F2Ifloor))) {
195 /* not coercible to in integer */
196 lua_Number flim; /* try to convert to float */
197 if (!tonumber(lim, &flim)) /* cannot convert to float? */
198 luaG_forerror(L, lim, "limit");
199 /* else 'flim' is a float out of integer bounds */
200 if (luai_numlt(0, flim)) { /* if it is positive, it is too large */
201 if (step < 0) return 1; /* initial value must be less than it */
202 *p = LUA_MAXINTEGER; /* truncate */
203 }
204 else { /* it is less than min integer */
205 if (step > 0) return 1; /* initial value must be greater than it */
206 *p = LUA_MININTEGER; /* truncate */
207 }
208 }
209 return (step > 0 ? init > *p : init < *p); /* not to run? */
210 }
211 #endif /* _KERNEL */
212
213
214 /*
215 ** Prepare a numerical for loop (opcode OP_FORPREP).
216 ** Return true to skip the loop. Otherwise,
217 ** after preparation, stack will be as follows:
218 ** ra : internal index (safe copy of the control variable)
219 ** ra + 1 : loop counter (integer loops) or limit (float loops)
220 ** ra + 2 : step
221 ** ra + 3 : control variable
222 */
223 static int forprep (lua_State *L, StkId ra) {
224 TValue *pinit = s2v(ra);
225 TValue *plimit = s2v(ra + 1);
226 TValue *pstep = s2v(ra + 2);
227 #ifndef _KERNEL
228 if (ttisinteger(pinit) && ttisinteger(pstep)) { /* integer loop? */
229 #endif /* _KERNEL */
230 lua_Integer init = ivalue(pinit);
231 lua_Integer step = ivalue(pstep);
232 lua_Integer limit;
233 if (step == 0)
234 luaG_runerror(L, "'for' step is zero");
235 setivalue(s2v(ra + 3), init); /* control variable */
236 #ifndef _KERNEL
237 if (forlimit(L, init, plimit, &limit, step))
238 return 1; /* skip the loop */
239 else { /* prepare loop counter */
240 #endif /* _KERNEL */
241 lua_Unsigned count;
242 if (step > 0) { /* ascending loop? */
243 count = l_castS2U(limit) - l_castS2U(init);
244 if (step != 1) /* avoid division in the too common case */
245 count /= l_castS2U(step);
246 }
247 else { /* step < 0; descending loop */
248 count = l_castS2U(init) - l_castS2U(limit);
249 /* 'step+1' avoids negating 'mininteger' */
250 count /= l_castS2U(-(step + 1)) + 1u;
251 }
252 /* store the counter in place of the limit (which won't be
253 needed anymore) */
254 setivalue(plimit, l_castU2S(count));
255 #ifndef _KERNEL
256 }
257 }
258 else { /* try making all values floats */
259 lua_Number init; lua_Number limit; lua_Number step;
260 if (l_unlikely(!tonumber(plimit, &limit)))
261 luaG_forerror(L, plimit, "limit");
262 if (l_unlikely(!tonumber(pstep, &step)))
263 luaG_forerror(L, pstep, "step");
264 if (l_unlikely(!tonumber(pinit, &init)))
265 luaG_forerror(L, pinit, "initial value");
266 if (step == 0)
267 luaG_runerror(L, "'for' step is zero");
268 if (luai_numlt(0, step) ? luai_numlt(limit, init)
269 : luai_numlt(init, limit))
270 return 1; /* skip the loop */
271 else {
272 /* make sure internal values are all floats */
273 setfltvalue(plimit, limit);
274 setfltvalue(pstep, step);
275 setfltvalue(s2v(ra), init); /* internal index */
276 setfltvalue(s2v(ra + 3), init); /* control variable */
277 }
278 }
279 #endif /* _KERNEL */
280 return 0;
281 }
282
283
284 #ifndef _KERNEL
285 /*
286 ** Execute a step of a float numerical for loop, returning
287 ** true iff the loop must continue. (The integer case is
288 ** written online with opcode OP_FORLOOP, for performance.)
289 */
290 static int floatforloop (StkId ra) {
291 lua_Number step = fltvalue(s2v(ra + 2));
292 lua_Number limit = fltvalue(s2v(ra + 1));
293 lua_Number idx = fltvalue(s2v(ra)); /* internal index */
294 idx = luai_numadd(L, idx, step); /* increment index */
295 if (luai_numlt(0, step) ? luai_numle(idx, limit)
296 : luai_numle(limit, idx)) {
297 chgfltvalue(s2v(ra), idx); /* update internal index */
298 setfltvalue(s2v(ra + 3), idx); /* and control variable */
299 return 1; /* jump back */
300 }
301 else
302 return 0; /* finish the loop */
303 }
304 #endif /* _KERNEL */
305
306
307 /*
308 ** Finish the table access 'val = t[key]'.
309 ** if 'slot' is NULL, 't' is not a table; otherwise, 'slot' points to
310 ** t[k] entry (which must be empty).
311 */
312 void luaV_finishget (lua_State *L, const TValue *t, TValue *key, StkId val,
313 const TValue *slot) {
314 int loop; /* counter to avoid infinite loops */
315 const TValue *tm; /* metamethod */
316 for (loop = 0; loop < MAXTAGLOOP; loop++) {
317 if (slot == NULL) { /* 't' is not a table? */
318 lua_assert(!ttistable(t));
319 tm = luaT_gettmbyobj(L, t, TM_INDEX);
320 if (l_unlikely(notm(tm)))
321 luaG_typeerror(L, t, "index"); /* no metamethod */
322 /* else will try the metamethod */
323 }
324 else { /* 't' is a table */
325 lua_assert(isempty(slot));
326 tm = fasttm(L, hvalue(t)->metatable, TM_INDEX); /* table's metamethod */
327 if (tm == NULL) { /* no metamethod? */
328 setnilvalue(s2v(val)); /* result is nil */
329 return;
330 }
331 /* else will try the metamethod */
332 }
333 if (ttisfunction(tm)) { /* is metamethod a function? */
334 luaT_callTMres(L, tm, t, key, val); /* call it */
335 return;
336 }
337 t = tm; /* else try to access 'tm[key]' */
338 if (luaV_fastget(L, t, key, slot, luaH_get)) { /* fast track? */
339 setobj2s(L, val, slot); /* done */
340 return;
341 }
342 /* else repeat (tail call 'luaV_finishget') */
343 }
344 luaG_runerror(L, "'__index' chain too long; possible loop");
345 }
346
347
348 /*
349 ** Finish a table assignment 't[key] = val'.
350 ** If 'slot' is NULL, 't' is not a table. Otherwise, 'slot' points
351 ** to the entry 't[key]', or to a value with an absent key if there
352 ** is no such entry. (The value at 'slot' must be empty, otherwise
353 ** 'luaV_fastget' would have done the job.)
354 */
355 void luaV_finishset (lua_State *L, const TValue *t, TValue *key,
356 TValue *val, const TValue *slot) {
357 int loop; /* counter to avoid infinite loops */
358 for (loop = 0; loop < MAXTAGLOOP; loop++) {
359 const TValue *tm; /* '__newindex' metamethod */
360 if (slot != NULL) { /* is 't' a table? */
361 Table *h = hvalue(t); /* save 't' table */
362 lua_assert(isempty(slot)); /* slot must be empty */
363 tm = fasttm(L, h->metatable, TM_NEWINDEX); /* get metamethod */
364 if (tm == NULL) { /* no metamethod? */
365 luaH_finishset(L, h, key, slot, val); /* set new value */
366 invalidateTMcache(h);
367 luaC_barrierback(L, obj2gco(h), val);
368 return;
369 }
370 /* else will try the metamethod */
371 }
372 else { /* not a table; check metamethod */
373 tm = luaT_gettmbyobj(L, t, TM_NEWINDEX);
374 if (l_unlikely(notm(tm)))
375 luaG_typeerror(L, t, "index");
376 }
377 /* try the metamethod */
378 if (ttisfunction(tm)) {
379 luaT_callTM(L, tm, t, key, val);
380 return;
381 }
382 t = tm; /* else repeat assignment over 'tm' */
383 if (luaV_fastget(L, t, key, slot, luaH_get)) {
384 luaV_finishfastset(L, t, slot, val);
385 return; /* done */
386 }
387 /* else 'return luaV_finishset(L, t, key, val, slot)' (loop) */
388 }
389 luaG_runerror(L, "'__newindex' chain too long; possible loop");
390 }
391
392
393 /*
394 ** Compare two strings 'ls' x 'rs', returning an integer less-equal-
395 ** -greater than zero if 'ls' is less-equal-greater than 'rs'.
396 ** The code is a little tricky because it allows '\0' in the strings
397 ** and it uses 'strcoll' (to respect locales) for each segments
398 ** of the strings.
399 */
400 static int l_strcmp (const TString *ls, const TString *rs) {
401 const char *l = getstr(ls);
402 size_t ll = tsslen(ls);
403 const char *r = getstr(rs);
404 size_t lr = tsslen(rs);
405 for (;;) { /* for each segment */
406 int temp = strcoll(l, r);
407 if (temp != 0) /* not equal? */
408 return temp; /* done */
409 else { /* strings are equal up to a '\0' */
410 size_t len = strlen(l); /* index of first '\0' in both strings */
411 if (len == lr) /* 'rs' is finished? */
412 return (len == ll) ? 0 : 1; /* check 'ls' */
413 else if (len == ll) /* 'ls' is finished? */
414 return -1; /* 'ls' is less than 'rs' ('rs' is not finished) */
415 /* both strings longer than 'len'; go on comparing after the '\0' */
416 len++;
417 l += len; ll -= len; r += len; lr -= len;
418 }
419 }
420 }
421
422
423 #ifndef _KERNEL
424 /*
425 ** Check whether integer 'i' is less than float 'f'. If 'i' has an
426 ** exact representation as a float ('l_intfitsf'), compare numbers as
427 ** floats. Otherwise, use the equivalence 'i < f <=> i < ceil(f)'.
428 ** If 'ceil(f)' is out of integer range, either 'f' is greater than
429 ** all integers or less than all integers.
430 ** (The test with 'l_intfitsf' is only for performance; the else
431 ** case is correct for all values, but it is slow due to the conversion
432 ** from float to int.)
433 ** When 'f' is NaN, comparisons must result in false.
434 */
435 l_sinline int LTintfloat (lua_Integer i, lua_Number f) {
436 if (l_intfitsf(i))
437 return luai_numlt(cast_num(i), f); /* compare them as floats */
438 else { /* i < f <=> i < ceil(f) */
439 lua_Integer fi;
440 if (luaV_flttointeger(f, &fi, F2Iceil)) /* fi = ceil(f) */
441 return i < fi; /* compare them as integers */
442 else /* 'f' is either greater or less than all integers */
443 return f > 0; /* greater? */
444 }
445 }
446
447
448 /*
449 ** Check whether integer 'i' is less than or equal to float 'f'.
450 ** See comments on previous function.
451 */
452 l_sinline int LEintfloat (lua_Integer i, lua_Number f) {
453 if (l_intfitsf(i))
454 return luai_numle(cast_num(i), f); /* compare them as floats */
455 else { /* i <= f <=> i <= floor(f) */
456 lua_Integer fi;
457 if (luaV_flttointeger(f, &fi, F2Ifloor)) /* fi = floor(f) */
458 return i <= fi; /* compare them as integers */
459 else /* 'f' is either greater or less than all integers */
460 return f > 0; /* greater? */
461 }
462 }
463
464
465 /*
466 ** Check whether float 'f' is less than integer 'i'.
467 ** See comments on previous function.
468 */
469 l_sinline int LTfloatint (lua_Number f, lua_Integer i) {
470 if (l_intfitsf(i))
471 return luai_numlt(f, cast_num(i)); /* compare them as floats */
472 else { /* f < i <=> floor(f) < i */
473 lua_Integer fi;
474 if (luaV_flttointeger(f, &fi, F2Ifloor)) /* fi = floor(f) */
475 return fi < i; /* compare them as integers */
476 else /* 'f' is either greater or less than all integers */
477 return f < 0; /* less? */
478 }
479 }
480
481
482 /*
483 ** Check whether float 'f' is less than or equal to integer 'i'.
484 ** See comments on previous function.
485 */
486 l_sinline int LEfloatint (lua_Number f, lua_Integer i) {
487 if (l_intfitsf(i))
488 return luai_numle(f, cast_num(i)); /* compare them as floats */
489 else { /* f <= i <=> ceil(f) <= i */
490 lua_Integer fi;
491 if (luaV_flttointeger(f, &fi, F2Iceil)) /* fi = ceil(f) */
492 return fi <= i; /* compare them as integers */
493 else /* 'f' is either greater or less than all integers */
494 return f < 0; /* less? */
495 }
496 }
497 #endif /* _KERNEL */
498
499
500 /*
501 ** Return 'l < r', for numbers.
502 */
503 l_sinline int LTnum (const TValue *l, const TValue *r) {
504 #ifndef _KERNEL
505 lua_assert(ttisnumber(l) && ttisnumber(r));
506 if (ttisinteger(l)) {
507 lua_Integer li = ivalue(l);
508 if (ttisinteger(r))
509 return li < ivalue(r); /* both are integers */
510 else /* 'l' is int and 'r' is float */
511 return LTintfloat(li, fltvalue(r)); /* l < r ? */
512 }
513 else {
514 lua_Number lf = fltvalue(l); /* 'l' must be float */
515 if (ttisfloat(r))
516 return luai_numlt(lf, fltvalue(r)); /* both are float */
517 else /* 'l' is float and 'r' is int */
518 return LTfloatint(lf, ivalue(r));
519 }
520 #else
521 lua_assert(ttisnumber(l));
522 lua_assert(ttisnumber(r));
523 return ivalue(l) < ivalue(r); /* both are integers */
524 #endif /* _KERNEL */
525 }
526
527
528 /*
529 ** Return 'l <= r', for numbers.
530 */
531 l_sinline int LEnum (const TValue *l, const TValue *r) {
532 #ifndef _KERNEL
533 lua_assert(ttisnumber(l) && ttisnumber(r));
534 if (ttisinteger(l)) {
535 lua_Integer li = ivalue(l);
536 if (ttisinteger(r))
537 return li <= ivalue(r); /* both are integers */
538 else /* 'l' is int and 'r' is float */
539 return LEintfloat(li, fltvalue(r)); /* l <= r ? */
540 }
541 else {
542 lua_Number lf = fltvalue(l); /* 'l' must be float */
543 if (ttisfloat(r))
544 return luai_numle(lf, fltvalue(r)); /* both are float */
545 else /* 'l' is float and 'r' is int */
546 return LEfloatint(lf, ivalue(r));
547 }
548 #else
549 lua_assert(ttisinteger(l));
550 lua_assert(ttisinteger(r));
551 return ivalue(l) <= ivalue(r); /* both are integers */
552 #endif /* _KERNEL */
553 }
554
555
556 /*
557 ** return 'l < r' for non-numbers.
558 */
559 static int lessthanothers (lua_State *L, const TValue *l, const TValue *r) {
560 lua_assert(!ttisnumber(l) || !ttisnumber(r));
561 if (ttisstring(l) && ttisstring(r)) /* both are strings? */
562 return l_strcmp(tsvalue(l), tsvalue(r)) < 0;
563 else
564 return luaT_callorderTM(L, l, r, TM_LT);
565 }
566
567
568 /*
569 ** Main operation less than; return 'l < r'.
570 */
571 int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) {
572 #ifndef _KERNEL
573 if (ttisnumber(l) && ttisnumber(r)) /* both operands are numbers? */
574 return LTnum(l, r);
575 #else /* _KERNEL */
576 if (ttisinteger(l) && ttisinteger(r)) /* both operands are integers? */
577 return (ivalue(l) < ivalue(r));
578 #endif /* _KERNEL */
579 else return lessthanothers(L, l, r);
580 }
581
582
583 /*
584 ** return 'l <= r' for non-numbers.
585 */
586 static int lessequalothers (lua_State *L, const TValue *l, const TValue *r) {
587 lua_assert(!ttisnumber(l) || !ttisnumber(r));
588 if (ttisstring(l) && ttisstring(r)) /* both are strings? */
589 return l_strcmp(tsvalue(l), tsvalue(r)) <= 0;
590 else
591 return luaT_callorderTM(L, l, r, TM_LE);
592 }
593
594
595 /*
596 ** Main operation less than or equal to; return 'l <= r'.
597 */
598 int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r) {
599 if (ttisnumber(l) && ttisnumber(r)) /* both operands are numbers? */
600 return LEnum(l, r);
601 else return lessequalothers(L, l, r);
602 }
603
604
605 /*
606 ** Main operation for equality of Lua values; return 't1 == t2'.
607 ** L == NULL means raw equality (no metamethods)
608 */
609 int luaV_equalobj (lua_State *L, const TValue *t1, const TValue *t2) {
610 const TValue *tm;
611 if (ttypetag(t1) != ttypetag(t2)) { /* not the same variant? */
612 if (ttype(t1) != ttype(t2) || ttype(t1) != LUA_TNUMBER)
613 return 0; /* only numbers can be equal with different variants */
614 else { /* two numbers with different variants */
615 /* One of them is an integer. If the other does not have an
616 integer value, they cannot be equal; otherwise, compare their
617 integer values. */
618 lua_Integer i1, i2;
619 return (luaV_tointegerns(t1, &i1, F2Ieq) &&
620 luaV_tointegerns(t2, &i2, F2Ieq) &&
621 i1 == i2);
622 }
623 }
624 /* values have same type and same variant */
625 switch (ttypetag(t1)) {
626 case LUA_VNIL: case LUA_VFALSE: case LUA_VTRUE: return 1;
627 case LUA_VNUMINT: return (ivalue(t1) == ivalue(t2));
628 #ifndef _KERNEL
629 case LUA_VNUMFLT: return luai_numeq(fltvalue(t1), fltvalue(t2));
630 #endif /* _KERNEL */
631 case LUA_VLIGHTUSERDATA: return pvalue(t1) == pvalue(t2);
632 case LUA_VLCF: return fvalue(t1) == fvalue(t2);
633 case LUA_VSHRSTR: return eqshrstr(tsvalue(t1), tsvalue(t2));
634 case LUA_VLNGSTR: return luaS_eqlngstr(tsvalue(t1), tsvalue(t2));
635 case LUA_VUSERDATA: {
636 if (uvalue(t1) == uvalue(t2)) return 1;
637 else if (L == NULL) return 0;
638 tm = fasttm(L, uvalue(t1)->metatable, TM_EQ);
639 if (tm == NULL)
640 tm = fasttm(L, uvalue(t2)->metatable, TM_EQ);
641 break; /* will try TM */
642 }
643 case LUA_VTABLE: {
644 if (hvalue(t1) == hvalue(t2)) return 1;
645 else if (L == NULL) return 0;
646 tm = fasttm(L, hvalue(t1)->metatable, TM_EQ);
647 if (tm == NULL)
648 tm = fasttm(L, hvalue(t2)->metatable, TM_EQ);
649 break; /* will try TM */
650 }
651 default:
652 return gcvalue(t1) == gcvalue(t2);
653 }
654 if (tm == NULL) /* no TM? */
655 return 0; /* objects are different */
656 else {
657 luaT_callTMres(L, tm, t1, t2, L->top.p); /* call TM */
658 return !l_isfalse(s2v(L->top.p));
659 }
660 }
661
662
663 /* macro used by 'luaV_concat' to ensure that element at 'o' is a string */
664 #define tostring(L,o) \
665 (ttisstring(o) || (cvt2str(o) && (luaO_tostring(L, o), 1)))
666
667 #define isemptystr(o) (ttisshrstring(o) && tsvalue(o)->shrlen == 0)
668
669 /* copy strings in stack from top - n up to top - 1 to buffer */
670 static void copy2buff (StkId top, int n, char *buff) {
671 size_t tl = 0; /* size already copied */
672 do {
673 size_t l = vslen(s2v(top - n)); /* length of string being copied */
674 memcpy(buff + tl, svalue(s2v(top - n)), l * sizeof(char));
675 tl += l;
676 } while (--n > 0);
677 }
678
679
680 /*
681 ** Main operation for concatenation: concat 'total' values in the stack,
682 ** from 'L->top.p - total' up to 'L->top.p - 1'.
683 */
684 void luaV_concat (lua_State *L, int total) {
685 if (total == 1)
686 return; /* "all" values already concatenated */
687 do {
688 StkId top = L->top.p;
689 int n = 2; /* number of elements handled in this pass (at least 2) */
690 if (!(ttisstring(s2v(top - 2)) || cvt2str(s2v(top - 2))) ||
691 !tostring(L, s2v(top - 1)))
692 luaT_tryconcatTM(L); /* may invalidate 'top' */
693 else if (isemptystr(s2v(top - 1))) /* second operand is empty? */
694 cast_void(tostring(L, s2v(top - 2))); /* result is first operand */
695 else if (isemptystr(s2v(top - 2))) { /* first operand is empty string? */
696 setobjs2s(L, top - 2, top - 1); /* result is second op. */
697 }
698 else {
699 /* at least two non-empty string values; get as many as possible */
700 size_t tl = vslen(s2v(top - 1));
701 TString *ts;
702 /* collect total length and number of strings */
703 for (n = 1; n < total && tostring(L, s2v(top - n - 1)); n++) {
704 size_t l = vslen(s2v(top - n - 1));
705 if (l_unlikely(l >= (MAX_SIZE/sizeof(char)) - tl)) {
706 L->top.p = top - total; /* pop strings to avoid wasting stack */
707 luaG_runerror(L, "string length overflow");
708 }
709 tl += l;
710 }
711 if (tl <= LUAI_MAXSHORTLEN) { /* is result a short string? */
712 char buff[LUAI_MAXSHORTLEN];
713 copy2buff(top, n, buff); /* copy strings to buffer */
714 ts = luaS_newlstr(L, buff, tl);
715 }
716 else { /* long string; copy strings directly to final result */
717 ts = luaS_createlngstrobj(L, tl);
718 copy2buff(top, n, getstr(ts));
719 }
720 setsvalue2s(L, top - n, ts); /* create result */
721 }
722 total -= n - 1; /* got 'n' strings to create one new */
723 L->top.p -= n - 1; /* popped 'n' strings and pushed one */
724 } while (total > 1); /* repeat until only 1 result left */
725 }
726
727
728 /*
729 ** Main operation 'ra = #rb'.
730 */
731 void luaV_objlen (lua_State *L, StkId ra, const TValue *rb) {
732 const TValue *tm;
733 switch (ttypetag(rb)) {
734 case LUA_VTABLE: {
735 Table *h = hvalue(rb);
736 tm = fasttm(L, h->metatable, TM_LEN);
737 if (tm) break; /* metamethod? break switch to call it */
738 setivalue(s2v(ra), luaH_getn(h)); /* else primitive len */
739 return;
740 }
741 case LUA_VSHRSTR: {
742 setivalue(s2v(ra), tsvalue(rb)->shrlen);
743 return;
744 }
745 case LUA_VLNGSTR: {
746 setivalue(s2v(ra), tsvalue(rb)->u.lnglen);
747 return;
748 }
749 default: { /* try metamethod */
750 tm = luaT_gettmbyobj(L, rb, TM_LEN);
751 if (l_unlikely(notm(tm))) /* no metamethod? */
752 luaG_typeerror(L, rb, "get length of");
753 break;
754 }
755 }
756 luaT_callTMres(L, tm, rb, rb, ra);
757 }
758
759
760 /*
761 ** Integer division; return 'm // n', that is, floor(m/n).
762 ** C division truncates its result (rounds towards zero).
763 ** 'floor(q) == trunc(q)' when 'q >= 0' or when 'q' is integer,
764 ** otherwise 'floor(q) == trunc(q) - 1'.
765 */
766 lua_Integer luaV_idiv (lua_State *L, lua_Integer m, lua_Integer n) {
767 if (l_unlikely(l_castS2U(n) + 1u <= 1u)) { /* special cases: -1 or 0 */
768 if (n == 0)
769 luaG_runerror(L, "attempt to divide by zero");
770 return intop(-, 0, m); /* n==-1; avoid overflow with 0x80000...//-1 */
771 }
772 else {
773 lua_Integer q = m / n; /* perform C division */
774 if ((m ^ n) < 0 && m % n != 0) /* 'm/n' would be negative non-integer? */
775 q -= 1; /* correct result for different rounding */
776 return q;
777 }
778 }
779
780
781 /*
782 ** Integer modulus; return 'm % n'. (Assume that C '%' with
783 ** negative operands follows C99 behavior. See previous comment
784 ** about luaV_idiv.)
785 */
786 lua_Integer luaV_mod (lua_State *L, lua_Integer m, lua_Integer n) {
787 if (l_unlikely(l_castS2U(n) + 1u <= 1u)) { /* special cases: -1 or 0 */
788 if (n == 0)
789 luaG_runerror(L, "attempt to perform 'n%%0'");
790 return 0; /* m % -1 == 0; avoid overflow with 0x80000...%-1 */
791 }
792 else {
793 lua_Integer r = m % n;
794 if (r != 0 && (r ^ n) < 0) /* 'm/n' would be non-integer negative? */
795 r += n; /* correct result for different rounding */
796 return r;
797 }
798 }
799
800
801 #ifndef _KERNEL
802 /*
803 ** Float modulus
804 */
805 lua_Number luaV_modf (lua_State *L, lua_Number m, lua_Number n) {
806 lua_Number r;
807 luai_nummod(L, m, n, r);
808 return r;
809 }
810 #endif /* _KERNEL */
811
812
813 /* number of bits in an integer */
814 #define NBITS cast_int(sizeof(lua_Integer) * CHAR_BIT)
815
816
817 /*
818 ** Shift left operation. (Shift right just negates 'y'.)
819 */
820 lua_Integer luaV_shiftl (lua_Integer x, lua_Integer y) {
821 if (y < 0) { /* shift right? */
822 if (y <= -NBITS) return 0;
823 else return intop(>>, x, -y);
824 }
825 else { /* shift left */
826 if (y >= NBITS) return 0;
827 else return intop(<<, x, y);
828 }
829 }
830
831
832 /*
833 ** create a new Lua closure, push it in the stack, and initialize
834 ** its upvalues.
835 */
836 static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base,
837 StkId ra) {
838 int nup = p->sizeupvalues;
839 Upvaldesc *uv = p->upvalues;
840 int i;
841 LClosure *ncl = luaF_newLclosure(L, nup);
842 ncl->p = p;
843 setclLvalue2s(L, ra, ncl); /* anchor new closure in stack */
844 for (i = 0; i < nup; i++) { /* fill in its upvalues */
845 if (uv[i].instack) /* upvalue refers to local variable? */
846 ncl->upvals[i] = luaF_findupval(L, base + uv[i].idx);
847 else /* get upvalue from enclosing function */
848 ncl->upvals[i] = encup[uv[i].idx];
849 luaC_objbarrier(L, ncl, ncl->upvals[i]);
850 }
851 }
852
853
854 /*
855 ** finish execution of an opcode interrupted by a yield
856 */
857 void luaV_finishOp (lua_State *L) {
858 CallInfo *ci = L->ci;
859 StkId base = ci->func.p + 1;
860 Instruction inst = *(ci->u.l.savedpc - 1); /* interrupted instruction */
861 OpCode op = GET_OPCODE(inst);
862 switch (op) { /* finish its execution */
863 case OP_MMBIN: case OP_MMBINI: case OP_MMBINK: {
864 setobjs2s(L, base + GETARG_A(*(ci->u.l.savedpc - 2)), --L->top.p);
865 break;
866 }
867 case OP_UNM: case OP_BNOT: case OP_LEN:
868 case OP_GETTABUP: case OP_GETTABLE: case OP_GETI:
869 case OP_GETFIELD: case OP_SELF: {
870 setobjs2s(L, base + GETARG_A(inst), --L->top.p);
871 break;
872 }
873 case OP_LT: case OP_LE:
874 case OP_LTI: case OP_LEI:
875 case OP_GTI: case OP_GEI:
876 case OP_EQ: { /* note that 'OP_EQI'/'OP_EQK' cannot yield */
877 int res = !l_isfalse(s2v(L->top.p - 1));
878 L->top.p--;
879 #if defined(LUA_COMPAT_LT_LE)
880 if (ci->callstatus & CIST_LEQ) { /* "<=" using "<" instead? */
881 ci->callstatus ^= CIST_LEQ; /* clear mark */
882 res = !res; /* negate result */
883 }
884 #endif
885 lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_JMP);
886 if (res != GETARG_k(inst)) /* condition failed? */
887 ci->u.l.savedpc++; /* skip jump instruction */
888 break;
889 }
890 case OP_CONCAT: {
891 StkId top = L->top.p - 1; /* top when 'luaT_tryconcatTM' was called */
892 int a = GETARG_A(inst); /* first element to concatenate */
893 int total = cast_int(top - 1 - (base + a)); /* yet to concatenate */
894 setobjs2s(L, top - 2, top); /* put TM result in proper position */
895 L->top.p = top - 1; /* top is one after last element (at top-2) */
896 luaV_concat(L, total); /* concat them (may yield again) */
897 break;
898 }
899 case OP_CLOSE: { /* yielded closing variables */
900 ci->u.l.savedpc--; /* repeat instruction to close other vars. */
901 break;
902 }
903 case OP_RETURN: { /* yielded closing variables */
904 StkId ra = base + GETARG_A(inst);
905 /* adjust top to signal correct number of returns, in case the
906 return is "up to top" ('isIT') */
907 L->top.p = ra + ci->u2.nres;
908 /* repeat instruction to close other vars. and complete the return */
909 ci->u.l.savedpc--;
910 break;
911 }
912 default: {
913 /* only these other opcodes can yield */
914 lua_assert(op == OP_TFORCALL || op == OP_CALL ||
915 op == OP_TAILCALL || op == OP_SETTABUP || op == OP_SETTABLE ||
916 op == OP_SETI || op == OP_SETFIELD);
917 break;
918 }
919 }
920 }
921
922
923
924
925 /*
926 ** {==================================================================
927 ** Macros for arithmetic/bitwise/comparison opcodes in 'luaV_execute'
928 ** ===================================================================
929 */
930
931 #define l_addi(L,a,b) intop(+, a, b)
932 #define l_subi(L,a,b) intop(-, a, b)
933 #define l_muli(L,a,b) intop(*, a, b)
934 #define l_band(a,b) intop(&, a, b)
935 #define l_bor(a,b) intop(|, a, b)
936 #define l_bxor(a,b) intop(^, a, b)
937
938 #define l_lti(a,b) (a < b)
939 #define l_lei(a,b) (a <= b)
940 #define l_gti(a,b) (a > b)
941 #define l_gei(a,b) (a >= b)
942
943
944 /*
945 ** Arithmetic operations with immediate operands. 'iop' is the integer
946 ** operation, 'fop' is the float operation.
947 */
948 #ifndef _KERNEL
949 #define op_arithI(L,iop,fop) { \
950 StkId ra = RA(i); \
951 TValue *v1 = vRB(i); \
952 int imm = GETARG_sC(i); \
953 if (ttisinteger(v1)) { \
954 lua_Integer iv1 = ivalue(v1); \
955 pc++; setivalue(s2v(ra), iop(L, iv1, imm)); \
956 } \
957 else if (ttisfloat(v1)) { \
958 lua_Number nb = fltvalue(v1); \
959 lua_Number fimm = cast_num(imm); \
960 pc++; setfltvalue(s2v(ra), fop(L, nb, fimm)); \
961 }}
962 #else /* _KERNEL */
963 #define op_arithI(L,iop,fop) { \
964 StkId ra = RA(i); \
965 TValue *v1 = vRB(i); \
966 int imm = GETARG_sC(i); \
967 if (ttisinteger(v1)) { \
968 lua_Integer iv1 = ivalue(v1); \
969 pc++; setivalue(s2v(ra), iop(L, iv1, imm)); \
970 }}
971 #endif
972
973
974 #ifndef _KERNEL
975 /*
976 ** Auxiliary function for arithmetic operations over floats and others
977 ** with two register operands.
978 */
979 #define op_arithf_aux(L,v1,v2,fop) { \
980 lua_Number n1; lua_Number n2; \
981 if (tonumberns(v1, n1) && tonumberns(v2, n2)) { \
982 pc++; setfltvalue(s2v(ra), fop(L, n1, n2)); \
983 }}
984
985
986 /*
987 ** Arithmetic operations over floats and others with register operands.
988 */
989 #define op_arithf(L,fop) { \
990 StkId ra = RA(i); \
991 TValue *v1 = vRB(i); \
992 TValue *v2 = vRC(i); \
993 op_arithf_aux(L, v1, v2, fop); }
994
995
996 /*
997 ** Arithmetic operations with K operands for floats.
998 */
999 #define op_arithfK(L,fop) { \
1000 StkId ra = RA(i); \
1001 TValue *v1 = vRB(i); \
1002 TValue *v2 = KC(i); lua_assert(ttisnumber(v2)); \
1003 op_arithf_aux(L, v1, v2, fop); }
1004 #endif /* _KERNEL */
1005
1006
1007 /*
1008 ** Arithmetic operations over integers and floats.
1009 */
1010 #ifndef _KERNEL
1011 #define op_arith_aux(L,v1,v2,iop,fop) { \
1012 StkId ra = RA(i); \
1013 if (ttisinteger(v1) && ttisinteger(v2)) { \
1014 lua_Integer i1 = ivalue(v1); lua_Integer i2 = ivalue(v2); \
1015 pc++; setivalue(s2v(ra), iop(L, i1, i2)); \
1016 } \
1017 else op_arithf_aux(L, v1, v2, fop); }
1018 #else /* _KERNEL */
1019 #define op_arith_aux(L,v1,v2,iop,fop) { \
1020 StkId ra = RA(i); \
1021 if (ttisinteger(v1) && ttisinteger(v2)) { \
1022 lua_Integer i1 = ivalue(v1); lua_Integer i2 = ivalue(v2); \
1023 pc++; setivalue(s2v(ra), iop(L, i1, i2)); \
1024 }}
1025 #endif
1026
1027
1028 /*
1029 ** Arithmetic operations with register operands.
1030 */
1031 #define op_arith(L,iop,fop) { \
1032 TValue *v1 = vRB(i); \
1033 TValue *v2 = vRC(i); \
1034 op_arith_aux(L, v1, v2, iop, fop); }
1035
1036
1037 /*
1038 ** Arithmetic operations with K operands.
1039 */
1040 #define op_arithK(L,iop,fop) { \
1041 TValue *v1 = vRB(i); \
1042 TValue *v2 = KC(i); lua_assert(ttisnumber(v2)); \
1043 op_arith_aux(L, v1, v2, iop, fop); }
1044
1045
1046 /*
1047 ** Bitwise operations with constant operand.
1048 */
1049 #define op_bitwiseK(L,op) { \
1050 StkId ra = RA(i); \
1051 TValue *v1 = vRB(i); \
1052 TValue *v2 = KC(i); \
1053 lua_Integer i1; \
1054 lua_Integer i2 = ivalue(v2); \
1055 if (tointegerns(v1, &i1)) { \
1056 pc++; setivalue(s2v(ra), op(i1, i2)); \
1057 }}
1058
1059
1060 /*
1061 ** Bitwise operations with register operands.
1062 */
1063 #define op_bitwise(L,op) { \
1064 StkId ra = RA(i); \
1065 TValue *v1 = vRB(i); \
1066 TValue *v2 = vRC(i); \
1067 lua_Integer i1; lua_Integer i2; \
1068 if (tointegerns(v1, &i1) && tointegerns(v2, &i2)) { \
1069 pc++; setivalue(s2v(ra), op(i1, i2)); \
1070 }}
1071
1072
1073 /*
1074 ** Order operations with register operands. 'opn' actually works
1075 ** for all numbers, but the fast track improves performance for
1076 ** integers.
1077 */
1078 #define op_order(L,opi,opn,other) { \
1079 StkId ra = RA(i); \
1080 int cond; \
1081 TValue *rb = vRB(i); \
1082 if (ttisinteger(s2v(ra)) && ttisinteger(rb)) { \
1083 lua_Integer ia = ivalue(s2v(ra)); \
1084 lua_Integer ib = ivalue(rb); \
1085 cond = opi(ia, ib); \
1086 } \
1087 else if (ttisnumber(s2v(ra)) && ttisnumber(rb)) \
1088 cond = opn(s2v(ra), rb); \
1089 else \
1090 Protect(cond = other(L, s2v(ra), rb)); \
1091 docondjump(); }
1092
1093
1094 /*
1095 ** Order operations with immediate operand. (Immediate operand is
1096 ** always small enough to have an exact representation as a float.)
1097 */
1098 #ifndef _KERNEL
1099 #define op_orderI(L,opi,opf,inv,tm) { \
1100 StkId ra = RA(i); \
1101 int cond; \
1102 int im = GETARG_sB(i); \
1103 if (ttisinteger(s2v(ra))) \
1104 cond = opi(ivalue(s2v(ra)), im); \
1105 else if (ttisfloat(s2v(ra))) { \
1106 lua_Number fa = fltvalue(s2v(ra)); \
1107 lua_Number fim = cast_num(im); \
1108 cond = opf(fa, fim); \
1109 } \
1110 else { \
1111 int isf = GETARG_C(i); \
1112 Protect(cond = luaT_callorderiTM(L, s2v(ra), im, inv, isf, tm)); \
1113 } \
1114 docondjump(); }
1115 #else /* _KERNEL */
1116 #define op_orderI(L,opi,opf,inv,tm) { \
1117 StkId ra = RA(i); \
1118 int cond; \
1119 int im = GETARG_sB(i); \
1120 if (ttisinteger(s2v(ra))) \
1121 cond = opi(ivalue(s2v(ra)), im); \
1122 else { \
1123 int isf = GETARG_C(i); \
1124 Protect(cond = luaT_callorderiTM(L, s2v(ra), im, inv, isf, tm)); \
1125 } \
1126 docondjump(); }
1127 #endif
1128
1129 /* }================================================================== */
1130
1131
1132 /*
1133 ** {==================================================================
1134 ** Function 'luaV_execute': main interpreter loop
1135 ** ===================================================================
1136 */
1137
1138 /*
1139 ** some macros for common tasks in 'luaV_execute'
1140 */
1141
1142
1143 #define RA(i) (base+GETARG_A(i))
1144 #define RB(i) (base+GETARG_B(i))
1145 #define vRB(i) s2v(RB(i))
1146 #define KB(i) (k+GETARG_B(i))
1147 #define RC(i) (base+GETARG_C(i))
1148 #define vRC(i) s2v(RC(i))
1149 #define KC(i) (k+GETARG_C(i))
1150 #define RKC(i) ((TESTARG_k(i)) ? k + GETARG_C(i) : s2v(base + GETARG_C(i)))
1151
1152
1153
1154 #define updatetrap(ci) (trap = ci->u.l.trap)
1155
1156 #define updatebase(ci) (base = ci->func.p + 1)
1157
1158
1159 #define updatestack(ci) \
1160 { if (l_unlikely(trap)) { updatebase(ci); ra = RA(i); } }
1161
1162
1163 /*
1164 ** Execute a jump instruction. The 'updatetrap' allows signals to stop
1165 ** tight loops. (Without it, the local copy of 'trap' could never change.)
1166 */
1167 #define dojump(ci,i,e) { pc += GETARG_sJ(i) + e; updatetrap(ci); }
1168
1169
1170 /* for test instructions, execute the jump instruction that follows it */
1171 #define donextjump(ci) { Instruction ni = *pc; dojump(ci, ni, 1); }
1172
1173 /*
1174 ** do a conditional jump: skip next instruction if 'cond' is not what
1175 ** was expected (parameter 'k'), else do next instruction, which must
1176 ** be a jump.
1177 */
1178 #define docondjump() if (cond != GETARG_k(i)) pc++; else donextjump(ci);
1179
1180
1181 /*
1182 ** Correct global 'pc'.
1183 */
1184 #define savepc(L) (ci->u.l.savedpc = pc)
1185
1186
1187 /*
1188 ** Whenever code can raise errors, the global 'pc' and the global
1189 ** 'top' must be correct to report occasional errors.
1190 */
1191 #define savestate(L,ci) (savepc(L), L->top.p = ci->top.p)
1192
1193
1194 /*
1195 ** Protect code that, in general, can raise errors, reallocate the
1196 ** stack, and change the hooks.
1197 */
1198 #define Protect(exp) (savestate(L,ci), (exp), updatetrap(ci))
1199
1200 /* special version that does not change the top */
1201 #define ProtectNT(exp) (savepc(L), (exp), updatetrap(ci))
1202
1203 /*
1204 ** Protect code that can only raise errors. (That is, it cannot change
1205 ** the stack or hooks.)
1206 */
1207 #define halfProtect(exp) (savestate(L,ci), (exp))
1208
1209 /* 'c' is the limit of live values in the stack */
1210 #define checkGC(L,c) \
1211 { luaC_condGC(L, (savepc(L), L->top.p = (c)), \
1212 updatetrap(ci)); \
1213 luai_threadyield(L); }
1214
1215
1216 /* fetch an instruction and prepare its execution */
1217 #define vmfetch() { \
1218 if (l_unlikely(trap)) { /* stack reallocation or hooks? */ \
1219 trap = luaG_traceexec(L, pc); /* handle hooks */ \
1220 updatebase(ci); /* correct stack */ \
1221 } \
1222 i = *(pc++); \
1223 }
1224
1225 #define vmdispatch(o) switch(o)
1226 #define vmcase(l) case l:
1227 #define vmbreak break
1228
1229
1230 void luaV_execute (lua_State *L, CallInfo *ci) {
1231 LClosure *cl;
1232 TValue *k;
1233 StkId base;
1234 const Instruction *pc;
1235 int trap;
1236 #if LUA_USE_JUMPTABLE
1237 #include "ljumptab.h"
1238 #endif
1239 startfunc:
1240 trap = L->hookmask;
1241 returning: /* trap already set */
1242 cl = clLvalue(s2v(ci->func.p));
1243 k = cl->p->k;
1244 pc = ci->u.l.savedpc;
1245 if (l_unlikely(trap)) {
1246 if (pc == cl->p->code) { /* first instruction (not resuming)? */
1247 if (cl->p->is_vararg)
1248 trap = 0; /* hooks will start after VARARGPREP instruction */
1249 else /* check 'call' hook */
1250 luaD_hookcall(L, ci);
1251 }
1252 ci->u.l.trap = 1; /* assume trap is on, for now */
1253 }
1254 base = ci->func.p + 1;
1255 /* main loop of interpreter */
1256 for (;;) {
1257 Instruction i; /* instruction being executed */
1258 vmfetch();
1259 #if 0
1260 /* low-level line tracing for debugging Lua */
1261 printf("line: %d\n", luaG_getfuncline(cl->p, pcRel(pc, cl->p)));
1262 #endif
1263 lua_assert(base == ci->func.p + 1);
1264 lua_assert(base <= L->top.p && L->top.p <= L->stack_last.p);
1265 /* invalidate top for instructions not expecting it */
1266 lua_assert(isIT(i) || (cast_void(L->top.p = base), 1));
1267 vmdispatch (GET_OPCODE(i)) {
1268 vmcase(OP_MOVE) {
1269 StkId ra = RA(i);
1270 setobjs2s(L, ra, RB(i));
1271 vmbreak;
1272 }
1273 vmcase(OP_LOADI) {
1274 StkId ra = RA(i);
1275 lua_Integer b = GETARG_sBx(i);
1276 setivalue(s2v(ra), b);
1277 vmbreak;
1278 }
1279 #ifndef _KERNEL
1280 vmcase(OP_LOADF) {
1281 StkId ra = RA(i);
1282 int b = GETARG_sBx(i);
1283 setfltvalue(s2v(ra), cast_num(b));
1284 vmbreak;
1285 }
1286 #endif /* _KERNEL */
1287 vmcase(OP_LOADK) {
1288 StkId ra = RA(i);
1289 TValue *rb = k + GETARG_Bx(i);
1290 setobj2s(L, ra, rb);
1291 vmbreak;
1292 }
1293 vmcase(OP_LOADKX) {
1294 StkId ra = RA(i);
1295 TValue *rb;
1296 rb = k + GETARG_Ax(*pc); pc++;
1297 setobj2s(L, ra, rb);
1298 vmbreak;
1299 }
1300 vmcase(OP_LOADFALSE) {
1301 StkId ra = RA(i);
1302 setbfvalue(s2v(ra));
1303 vmbreak;
1304 }
1305 vmcase(OP_LFALSESKIP) {
1306 StkId ra = RA(i);
1307 setbfvalue(s2v(ra));
1308 pc++; /* skip next instruction */
1309 vmbreak;
1310 }
1311 vmcase(OP_LOADTRUE) {
1312 StkId ra = RA(i);
1313 setbtvalue(s2v(ra));
1314 vmbreak;
1315 }
1316 vmcase(OP_LOADNIL) {
1317 StkId ra = RA(i);
1318 int b = GETARG_B(i);
1319 do {
1320 setnilvalue(s2v(ra++));
1321 } while (b--);
1322 vmbreak;
1323 }
1324 vmcase(OP_GETUPVAL) {
1325 StkId ra = RA(i);
1326 int b = GETARG_B(i);
1327 setobj2s(L, ra, cl->upvals[b]->v.p);
1328 vmbreak;
1329 }
1330 vmcase(OP_SETUPVAL) {
1331 StkId ra = RA(i);
1332 UpVal *uv = cl->upvals[GETARG_B(i)];
1333 setobj(L, uv->v.p, s2v(ra));
1334 luaC_barrier(L, uv, s2v(ra));
1335 vmbreak;
1336 }
1337 vmcase(OP_GETTABUP) {
1338 StkId ra = RA(i);
1339 const TValue *slot;
1340 TValue *upval = cl->upvals[GETARG_B(i)]->v.p;
1341 TValue *rc = KC(i);
1342 TString *key = tsvalue(rc); /* key must be a string */
1343 if (luaV_fastget(L, upval, key, slot, luaH_getshortstr)) {
1344 setobj2s(L, ra, slot);
1345 }
1346 else
1347 Protect(luaV_finishget(L, upval, rc, ra, slot));
1348 vmbreak;
1349 }
1350 vmcase(OP_GETTABLE) {
1351 StkId ra = RA(i);
1352 const TValue *slot;
1353 TValue *rb = vRB(i);
1354 TValue *rc = vRC(i);
1355 lua_Unsigned n;
1356 if (ttisinteger(rc) /* fast track for integers? */
1357 ? (cast_void(n = ivalue(rc)), luaV_fastgeti(L, rb, n, slot))
1358 : luaV_fastget(L, rb, rc, slot, luaH_get)) {
1359 setobj2s(L, ra, slot);
1360 }
1361 else
1362 Protect(luaV_finishget(L, rb, rc, ra, slot));
1363 vmbreak;
1364 }
1365 vmcase(OP_GETI) {
1366 StkId ra = RA(i);
1367 const TValue *slot;
1368 TValue *rb = vRB(i);
1369 int c = GETARG_C(i);
1370 if (luaV_fastgeti(L, rb, c, slot)) {
1371 setobj2s(L, ra, slot);
1372 }
1373 else {
1374 TValue key;
1375 setivalue(&key, c);
1376 Protect(luaV_finishget(L, rb, &key, ra, slot));
1377 }
1378 vmbreak;
1379 }
1380 vmcase(OP_GETFIELD) {
1381 StkId ra = RA(i);
1382 const TValue *slot;
1383 TValue *rb = vRB(i);
1384 TValue *rc = KC(i);
1385 TString *key = tsvalue(rc); /* key must be a string */
1386 if (luaV_fastget(L, rb, key, slot, luaH_getshortstr)) {
1387 setobj2s(L, ra, slot);
1388 }
1389 else
1390 Protect(luaV_finishget(L, rb, rc, ra, slot));
1391 vmbreak;
1392 }
1393 vmcase(OP_SETTABUP) {
1394 const TValue *slot;
1395 TValue *upval = cl->upvals[GETARG_A(i)]->v.p;
1396 TValue *rb = KB(i);
1397 TValue *rc = RKC(i);
1398 TString *key = tsvalue(rb); /* key must be a string */
1399 if (luaV_fastget(L, upval, key, slot, luaH_getshortstr)) {
1400 luaV_finishfastset(L, upval, slot, rc);
1401 }
1402 else
1403 Protect(luaV_finishset(L, upval, rb, rc, slot));
1404 vmbreak;
1405 }
1406 vmcase(OP_SETTABLE) {
1407 StkId ra = RA(i);
1408 const TValue *slot;
1409 TValue *rb = vRB(i); /* key (table is in 'ra') */
1410 TValue *rc = RKC(i); /* value */
1411 lua_Unsigned n;
1412 if (ttisinteger(rb) /* fast track for integers? */
1413 ? (cast_void(n = ivalue(rb)), luaV_fastgeti(L, s2v(ra), n, slot))
1414 : luaV_fastget(L, s2v(ra), rb, slot, luaH_get)) {
1415 luaV_finishfastset(L, s2v(ra), slot, rc);
1416 }
1417 else
1418 Protect(luaV_finishset(L, s2v(ra), rb, rc, slot));
1419 vmbreak;
1420 }
1421 vmcase(OP_SETI) {
1422 StkId ra = RA(i);
1423 const TValue *slot;
1424 int c = GETARG_B(i);
1425 TValue *rc = RKC(i);
1426 if (luaV_fastgeti(L, s2v(ra), c, slot)) {
1427 luaV_finishfastset(L, s2v(ra), slot, rc);
1428 }
1429 else {
1430 TValue key;
1431 setivalue(&key, c);
1432 Protect(luaV_finishset(L, s2v(ra), &key, rc, slot));
1433 }
1434 vmbreak;
1435 }
1436 vmcase(OP_SETFIELD) {
1437 StkId ra = RA(i);
1438 const TValue *slot;
1439 TValue *rb = KB(i);
1440 TValue *rc = RKC(i);
1441 TString *key = tsvalue(rb); /* key must be a string */
1442 if (luaV_fastget(L, s2v(ra), key, slot, luaH_getshortstr)) {
1443 luaV_finishfastset(L, s2v(ra), slot, rc);
1444 }
1445 else
1446 Protect(luaV_finishset(L, s2v(ra), rb, rc, slot));
1447 vmbreak;
1448 }
1449 vmcase(OP_NEWTABLE) {
1450 StkId ra = RA(i);
1451 int b = GETARG_B(i); /* log2(hash size) + 1 */
1452 int c = GETARG_C(i); /* array size */
1453 Table *t;
1454 if (b > 0)
1455 b = 1 << (b - 1); /* size is 2^(b - 1) */
1456 lua_assert((!TESTARG_k(i)) == (GETARG_Ax(*pc) == 0));
1457 if (TESTARG_k(i)) /* non-zero extra argument? */
1458 c += GETARG_Ax(*pc) * (MAXARG_C + 1); /* add it to size */
1459 pc++; /* skip extra argument */
1460 L->top.p = ra + 1; /* correct top in case of emergency GC */
1461 t = luaH_new(L); /* memory allocation */
1462 sethvalue2s(L, ra, t);
1463 if (b != 0 || c != 0)
1464 luaH_resize(L, t, c, b); /* idem */
1465 checkGC(L, ra + 1);
1466 vmbreak;
1467 }
1468 vmcase(OP_SELF) {
1469 StkId ra = RA(i);
1470 const TValue *slot;
1471 TValue *rb = vRB(i);
1472 TValue *rc = RKC(i);
1473 TString *key = tsvalue(rc); /* key must be a string */
1474 setobj2s(L, ra + 1, rb);
1475 if (luaV_fastget(L, rb, key, slot, luaH_getstr)) {
1476 setobj2s(L, ra, slot);
1477 }
1478 else
1479 Protect(luaV_finishget(L, rb, rc, ra, slot));
1480 vmbreak;
1481 }
1482 vmcase(OP_ADDI) {
1483 op_arithI(L, l_addi, luai_numadd);
1484 vmbreak;
1485 }
1486 vmcase(OP_ADDK) {
1487 op_arithK(L, l_addi, luai_numadd);
1488 vmbreak;
1489 }
1490 vmcase(OP_SUBK) {
1491 op_arithK(L, l_subi, luai_numsub);
1492 vmbreak;
1493 }
1494 vmcase(OP_MULK) {
1495 op_arithK(L, l_muli, luai_nummul);
1496 vmbreak;
1497 }
1498 vmcase(OP_MODK) {
1499 savestate(L, ci); /* in case of division by 0 */
1500 op_arithK(L, luaV_mod, luaV_modf);
1501 vmbreak;
1502 }
1503 #ifndef _KERNEL
1504 vmcase(OP_POWK) {
1505 op_arithfK(L, luai_numpow);
1506 vmbreak;
1507 }
1508 vmcase(OP_DIVK) {
1509 op_arithfK(L, luai_numdiv);
1510 vmbreak;
1511 }
1512 #endif /* _KERNEL */
1513 vmcase(OP_IDIVK) {
1514 savestate(L, ci); /* in case of division by 0 */
1515 op_arithK(L, luaV_idiv, luai_numidiv);
1516 vmbreak;
1517 }
1518 vmcase(OP_BANDK) {
1519 op_bitwiseK(L, l_band);
1520 vmbreak;
1521 }
1522 vmcase(OP_BORK) {
1523 op_bitwiseK(L, l_bor);
1524 vmbreak;
1525 }
1526 vmcase(OP_BXORK) {
1527 op_bitwiseK(L, l_bxor);
1528 vmbreak;
1529 }
1530 vmcase(OP_SHRI) {
1531 StkId ra = RA(i);
1532 TValue *rb = vRB(i);
1533 int ic = GETARG_sC(i);
1534 lua_Integer ib;
1535 if (tointegerns(rb, &ib)) {
1536 pc++; setivalue(s2v(ra), luaV_shiftl(ib, -ic));
1537 }
1538 vmbreak;
1539 }
1540 vmcase(OP_SHLI) {
1541 StkId ra = RA(i);
1542 TValue *rb = vRB(i);
1543 int ic = GETARG_sC(i);
1544 lua_Integer ib;
1545 if (tointegerns(rb, &ib)) {
1546 pc++; setivalue(s2v(ra), luaV_shiftl(ic, ib));
1547 }
1548 vmbreak;
1549 }
1550 vmcase(OP_ADD) {
1551 op_arith(L, l_addi, luai_numadd);
1552 vmbreak;
1553 }
1554 vmcase(OP_SUB) {
1555 op_arith(L, l_subi, luai_numsub);
1556 vmbreak;
1557 }
1558 vmcase(OP_MUL) {
1559 op_arith(L, l_muli, luai_nummul);
1560 vmbreak;
1561 }
1562 vmcase(OP_MOD) {
1563 savestate(L, ci); /* in case of division by 0 */
1564 op_arith(L, luaV_mod, luaV_modf);
1565 vmbreak;
1566 }
1567 #ifndef _KERNEL
1568 vmcase(OP_POW) {
1569 op_arithf(L, luai_numpow);
1570 vmbreak;
1571 }
1572 vmcase(OP_DIV) { /* float division (always with floats) */
1573 op_arithf(L, luai_numdiv);
1574 vmbreak;
1575 }
1576 #endif /* _KERNEL */
1577 vmcase(OP_IDIV) { /* floor division */
1578 savestate(L, ci); /* in case of division by 0 */
1579 op_arith(L, luaV_idiv, luai_numidiv);
1580 vmbreak;
1581 }
1582 vmcase(OP_BAND) {
1583 op_bitwise(L, l_band);
1584 vmbreak;
1585 }
1586 vmcase(OP_BOR) {
1587 op_bitwise(L, l_bor);
1588 vmbreak;
1589 }
1590 vmcase(OP_BXOR) {
1591 op_bitwise(L, l_bxor);
1592 vmbreak;
1593 }
1594 vmcase(OP_SHR) {
1595 op_bitwise(L, luaV_shiftr);
1596 vmbreak;
1597 }
1598 vmcase(OP_SHL) {
1599 op_bitwise(L, luaV_shiftl);
1600 vmbreak;
1601 }
1602 vmcase(OP_MMBIN) {
1603 StkId ra = RA(i);
1604 Instruction pi = *(pc - 2); /* original arith. expression */
1605 TValue *rb = vRB(i);
1606 TMS tm = (TMS)GETARG_C(i);
1607 StkId result = RA(pi);
1608 lua_assert(OP_ADD <= GET_OPCODE(pi) && GET_OPCODE(pi) <= OP_SHR);
1609 Protect(luaT_trybinTM(L, s2v(ra), rb, result, tm));
1610 vmbreak;
1611 }
1612 vmcase(OP_MMBINI) {
1613 StkId ra = RA(i);
1614 Instruction pi = *(pc - 2); /* original arith. expression */
1615 int imm = GETARG_sB(i);
1616 TMS tm = (TMS)GETARG_C(i);
1617 int flip = GETARG_k(i);
1618 StkId result = RA(pi);
1619 Protect(luaT_trybiniTM(L, s2v(ra), imm, flip, result, tm));
1620 vmbreak;
1621 }
1622 vmcase(OP_MMBINK) {
1623 StkId ra = RA(i);
1624 Instruction pi = *(pc - 2); /* original arith. expression */
1625 TValue *imm = KB(i);
1626 TMS tm = (TMS)GETARG_C(i);
1627 int flip = GETARG_k(i);
1628 StkId result = RA(pi);
1629 Protect(luaT_trybinassocTM(L, s2v(ra), imm, flip, result, tm));
1630 vmbreak;
1631 }
1632 vmcase(OP_UNM) {
1633 StkId ra = RA(i);
1634 TValue *rb = vRB(i);
1635 #ifndef _KERNEL
1636 lua_Number nb;
1637 if (ttisinteger(rb)) {
1638 lua_Integer ib = ivalue(rb);
1639 setivalue(s2v(ra), intop(-, 0, ib));
1640 }
1641 else if (tonumberns(rb, nb)) {
1642 setfltvalue(s2v(ra), luai_numunm(L, nb));
1643 }
1644 #else /* _KERNEL */
1645 lua_Integer ib;
1646 if (tointeger(rb, &ib)) {
1647 setivalue(s2v(ra), intop(-, 0, ib));
1648 }
1649 #endif /* _KERNEL */
1650 else
1651 Protect(luaT_trybinTM(L, rb, rb, ra, TM_UNM));
1652 vmbreak;
1653 }
1654 vmcase(OP_BNOT) {
1655 StkId ra = RA(i);
1656 TValue *rb = vRB(i);
1657 lua_Integer ib;
1658 if (tointegerns(rb, &ib)) {
1659 setivalue(s2v(ra), intop(^, ~l_castS2U(0), ib));
1660 }
1661 else
1662 Protect(luaT_trybinTM(L, rb, rb, ra, TM_BNOT));
1663 vmbreak;
1664 }
1665 vmcase(OP_NOT) {
1666 StkId ra = RA(i);
1667 TValue *rb = vRB(i);
1668 if (l_isfalse(rb))
1669 setbtvalue(s2v(ra));
1670 else
1671 setbfvalue(s2v(ra));
1672 vmbreak;
1673 }
1674 vmcase(OP_LEN) {
1675 StkId ra = RA(i);
1676 Protect(luaV_objlen(L, ra, vRB(i)));
1677 vmbreak;
1678 }
1679 vmcase(OP_CONCAT) {
1680 StkId ra = RA(i);
1681 int n = GETARG_B(i); /* number of elements to concatenate */
1682 L->top.p = ra + n; /* mark the end of concat operands */
1683 ProtectNT(luaV_concat(L, n));
1684 checkGC(L, L->top.p); /* 'luaV_concat' ensures correct top */
1685 vmbreak;
1686 }
1687 vmcase(OP_CLOSE) {
1688 StkId ra = RA(i);
1689 Protect(luaF_close(L, ra, LUA_OK, 1));
1690 vmbreak;
1691 }
1692 vmcase(OP_TBC) {
1693 StkId ra = RA(i);
1694 /* create new to-be-closed upvalue */
1695 halfProtect(luaF_newtbcupval(L, ra));
1696 vmbreak;
1697 }
1698 vmcase(OP_JMP) {
1699 dojump(ci, i, 0);
1700 vmbreak;
1701 }
1702 vmcase(OP_EQ) {
1703 StkId ra = RA(i);
1704 int cond;
1705 TValue *rb = vRB(i);
1706 Protect(cond = luaV_equalobj(L, s2v(ra), rb));
1707 docondjump();
1708 vmbreak;
1709 }
1710 vmcase(OP_LT) {
1711 op_order(L, l_lti, LTnum, lessthanothers);
1712 vmbreak;
1713 }
1714 vmcase(OP_LE) {
1715 op_order(L, l_lei, LEnum, lessequalothers);
1716 vmbreak;
1717 }
1718 vmcase(OP_EQK) {
1719 StkId ra = RA(i);
1720 TValue *rb = KB(i);
1721 /* basic types do not use '__eq'; we can use raw equality */
1722 int cond = luaV_rawequalobj(s2v(ra), rb);
1723 docondjump();
1724 vmbreak;
1725 }
1726 vmcase(OP_EQI) {
1727 StkId ra = RA(i);
1728 int cond;
1729 int im = GETARG_sB(i);
1730 if (ttisinteger(s2v(ra)))
1731 cond = (ivalue(s2v(ra)) == im);
1732 #ifndef _KERNEL
1733 else if (ttisfloat(s2v(ra)))
1734 cond = luai_numeq(fltvalue(s2v(ra)), cast_num(im));
1735 #endif /* _KERNEL */
1736 else
1737 cond = 0; /* other types cannot be equal to a number */
1738 docondjump();
1739 vmbreak;
1740 }
1741 vmcase(OP_LTI) {
1742 op_orderI(L, l_lti, luai_numlt, 0, TM_LT);
1743 vmbreak;
1744 }
1745 vmcase(OP_LEI) {
1746 op_orderI(L, l_lei, luai_numle, 0, TM_LE);
1747 vmbreak;
1748 }
1749 vmcase(OP_GTI) {
1750 op_orderI(L, l_gti, luai_numgt, 1, TM_LT);
1751 vmbreak;
1752 }
1753 vmcase(OP_GEI) {
1754 op_orderI(L, l_gei, luai_numge, 1, TM_LE);
1755 vmbreak;
1756 }
1757 vmcase(OP_TEST) {
1758 StkId ra = RA(i);
1759 int cond = !l_isfalse(s2v(ra));
1760 docondjump();
1761 vmbreak;
1762 }
1763 vmcase(OP_TESTSET) {
1764 StkId ra = RA(i);
1765 TValue *rb = vRB(i);
1766 if (l_isfalse(rb) == GETARG_k(i))
1767 pc++;
1768 else {
1769 setobj2s(L, ra, rb);
1770 donextjump(ci);
1771 }
1772 vmbreak;
1773 }
1774 vmcase(OP_CALL) {
1775 StkId ra = RA(i);
1776 CallInfo *newci;
1777 int b = GETARG_B(i);
1778 int nresults = GETARG_C(i) - 1;
1779 if (b != 0) /* fixed number of arguments? */
1780 L->top.p = ra + b; /* top signals number of arguments */
1781 /* else previous instruction set top */
1782 savepc(L); /* in case of errors */
1783 if ((newci = luaD_precall(L, ra, nresults)) == NULL)
1784 updatetrap(ci); /* C call; nothing else to be done */
1785 else { /* Lua call: run function in this same C frame */
1786 ci = newci;
1787 goto startfunc;
1788 }
1789 vmbreak;
1790 }
1791 vmcase(OP_TAILCALL) {
1792 StkId ra = RA(i);
1793 int b = GETARG_B(i); /* number of arguments + 1 (function) */
1794 int n; /* number of results when calling a C function */
1795 int nparams1 = GETARG_C(i);
1796 /* delta is virtual 'func' - real 'func' (vararg functions) */
1797 int delta = (nparams1) ? ci->u.l.nextraargs + nparams1 : 0;
1798 if (b != 0)
1799 L->top.p = ra + b;
1800 else /* previous instruction set top */
1801 b = cast_int(L->top.p - ra);
1802 savepc(ci); /* several calls here can raise errors */
1803 if (TESTARG_k(i)) {
1804 luaF_closeupval(L, base); /* close upvalues from current call */
1805 lua_assert(L->tbclist.p < base); /* no pending tbc variables */
1806 lua_assert(base == ci->func.p + 1);
1807 }
1808 if ((n = luaD_pretailcall(L, ci, ra, b, delta)) < 0) /* Lua function? */
1809 goto startfunc; /* execute the callee */
1810 else { /* C function? */
1811 ci->func.p -= delta; /* restore 'func' (if vararg) */
1812 luaD_poscall(L, ci, n); /* finish caller */
1813 updatetrap(ci); /* 'luaD_poscall' can change hooks */
1814 goto ret; /* caller returns after the tail call */
1815 }
1816 }
1817 vmcase(OP_RETURN) {
1818 StkId ra = RA(i);
1819 int n = GETARG_B(i) - 1; /* number of results */
1820 int nparams1 = GETARG_C(i);
1821 if (n < 0) /* not fixed? */
1822 n = cast_int(L->top.p - ra); /* get what is available */
1823 savepc(ci);
1824 if (TESTARG_k(i)) { /* may there be open upvalues? */
1825 ci->u2.nres = n; /* save number of returns */
1826 if (L->top.p < ci->top.p)
1827 L->top.p = ci->top.p;
1828 luaF_close(L, base, CLOSEKTOP, 1);
1829 updatetrap(ci);
1830 updatestack(ci);
1831 }
1832 if (nparams1) /* vararg function? */
1833 ci->func.p -= ci->u.l.nextraargs + nparams1;
1834 L->top.p = ra + n; /* set call for 'luaD_poscall' */
1835 luaD_poscall(L, ci, n);
1836 updatetrap(ci); /* 'luaD_poscall' can change hooks */
1837 goto ret;
1838 }
1839 vmcase(OP_RETURN0) {
1840 if (l_unlikely(L->hookmask)) {
1841 StkId ra = RA(i);
1842 L->top.p = ra;
1843 savepc(ci);
1844 luaD_poscall(L, ci, 0); /* no hurry... */
1845 trap = 1;
1846 }
1847 else { /* do the 'poscall' here */
1848 int nres;
1849 L->ci = ci->previous; /* back to caller */
1850 L->top.p = base - 1;
1851 for (nres = ci->nresults; l_unlikely(nres > 0); nres--)
1852 setnilvalue(s2v(L->top.p++)); /* all results are nil */
1853 }
1854 goto ret;
1855 }
1856 vmcase(OP_RETURN1) {
1857 if (l_unlikely(L->hookmask)) {
1858 StkId ra = RA(i);
1859 L->top.p = ra + 1;
1860 savepc(ci);
1861 luaD_poscall(L, ci, 1); /* no hurry... */
1862 trap = 1;
1863 }
1864 else { /* do the 'poscall' here */
1865 int nres = ci->nresults;
1866 L->ci = ci->previous; /* back to caller */
1867 if (nres == 0)
1868 L->top.p = base - 1; /* asked for no results */
1869 else {
1870 StkId ra = RA(i);
1871 setobjs2s(L, base - 1, ra); /* at least this result */
1872 L->top.p = base;
1873 for (; l_unlikely(nres > 1); nres--)
1874 setnilvalue(s2v(L->top.p++)); /* complete missing results */
1875 }
1876 }
1877 ret: /* return from a Lua function */
1878 if (ci->callstatus & CIST_FRESH)
1879 return; /* end this frame */
1880 else {
1881 ci = ci->previous;
1882 goto returning; /* continue running caller in this frame */
1883 }
1884 }
1885 vmcase(OP_FORLOOP) {
1886 StkId ra = RA(i);
1887 #ifndef _KERNEL
1888 if (ttisinteger(s2v(ra + 2))) { /* integer loop? */
1889 #endif /* _KERNEL */
1890 lua_Unsigned count = l_castS2U(ivalue(s2v(ra + 1)));
1891 if (count > 0) { /* still more iterations? */
1892 lua_Integer step = ivalue(s2v(ra + 2));
1893 lua_Integer idx = ivalue(s2v(ra)); /* internal index */
1894 chgivalue(s2v(ra + 1), count - 1); /* update counter */
1895 idx = intop(+, idx, step); /* add step to index */
1896 chgivalue(s2v(ra), idx); /* update internal index */
1897 setivalue(s2v(ra + 3), idx); /* and control variable */
1898 pc -= GETARG_Bx(i); /* jump back */
1899 }
1900 #ifndef _KERNEL
1901 }
1902 else if (floatforloop(ra)) /* float loop */
1903 pc -= GETARG_Bx(i); /* jump back */
1904 #endif /* _KERNEL */
1905 updatetrap(ci); /* allows a signal to break the loop */
1906 vmbreak;
1907 }
1908 vmcase(OP_FORPREP) {
1909 StkId ra = RA(i);
1910 savestate(L, ci); /* in case of errors */
1911 if (forprep(L, ra))
1912 pc += GETARG_Bx(i) + 1; /* skip the loop */
1913 vmbreak;
1914 }
1915 vmcase(OP_TFORPREP) {
1916 StkId ra = RA(i);
1917 /* create to-be-closed upvalue (if needed) */
1918 halfProtect(luaF_newtbcupval(L, ra + 3));
1919 pc += GETARG_Bx(i);
1920 i = *(pc++); /* go to next instruction */
1921 lua_assert(GET_OPCODE(i) == OP_TFORCALL && ra == RA(i));
1922 goto l_tforcall;
1923 }
1924 vmcase(OP_TFORCALL) {
1925 l_tforcall: {
1926 StkId ra = RA(i);
1927 /* 'ra' has the iterator function, 'ra + 1' has the state,
1928 'ra + 2' has the control variable, and 'ra + 3' has the
1929 to-be-closed variable. The call will use the stack after
1930 these values (starting at 'ra + 4')
1931 */
1932 /* push function, state, and control variable */
1933 memcpy(ra + 4, ra, 3 * sizeof(*ra));
1934 L->top.p = ra + 4 + 3;
1935 ProtectNT(luaD_call(L, ra + 4, GETARG_C(i))); /* do the call */
1936 updatestack(ci); /* stack may have changed */
1937 i = *(pc++); /* go to next instruction */
1938 lua_assert(GET_OPCODE(i) == OP_TFORLOOP && ra == RA(i));
1939 goto l_tforloop;
1940 }}
1941 vmcase(OP_TFORLOOP) {
1942 l_tforloop: {
1943 StkId ra = RA(i);
1944 if (!ttisnil(s2v(ra + 4))) { /* continue loop? */
1945 setobjs2s(L, ra + 2, ra + 4); /* save control variable */
1946 pc -= GETARG_Bx(i); /* jump back */
1947 }
1948 vmbreak;
1949 }}
1950 vmcase(OP_SETLIST) {
1951 StkId ra = RA(i);
1952 int n = GETARG_B(i);
1953 unsigned int last = GETARG_C(i);
1954 Table *h = hvalue(s2v(ra));
1955 if (n == 0)
1956 n = cast_int(L->top.p - ra) - 1; /* get up to the top */
1957 else
1958 L->top.p = ci->top.p; /* correct top in case of emergency GC */
1959 last += n;
1960 if (TESTARG_k(i)) {
1961 last += GETARG_Ax(*pc) * (MAXARG_C + 1);
1962 pc++;
1963 }
1964 if (last > luaH_realasize(h)) /* needs more space? */
1965 luaH_resizearray(L, h, last); /* preallocate it at once */
1966 for (; n > 0; n--) {
1967 TValue *val = s2v(ra + n);
1968 setobj2t(L, &h->array[last - 1], val);
1969 last--;
1970 luaC_barrierback(L, obj2gco(h), val);
1971 }
1972 vmbreak;
1973 }
1974 vmcase(OP_CLOSURE) {
1975 StkId ra = RA(i);
1976 Proto *p = cl->p->p[GETARG_Bx(i)];
1977 halfProtect(pushclosure(L, p, cl->upvals, base, ra));
1978 checkGC(L, ra + 1);
1979 vmbreak;
1980 }
1981 vmcase(OP_VARARG) {
1982 StkId ra = RA(i);
1983 int n = GETARG_C(i) - 1; /* required results */
1984 Protect(luaT_getvarargs(L, ci, ra, n));
1985 vmbreak;
1986 }
1987 vmcase(OP_VARARGPREP) {
1988 ProtectNT(luaT_adjustvarargs(L, GETARG_A(i), ci, cl->p));
1989 if (l_unlikely(trap)) { /* previous "Protect" updated trap */
1990 luaD_hookcall(L, ci);
1991 L->oldpc = 1; /* next opcode will be seen as a "new" line */
1992 }
1993 updatebase(ci); /* function has new base after adjustment */
1994 vmbreak;
1995 }
1996 vmcase(OP_EXTRAARG) {
1997 lua_assert(0);
1998 vmbreak;
1999 }
2000 }
2001 }
2002 }
2003
2004 /* }================================================================== */
2005