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*/
90static 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*/
103int 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*/
121int 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*/
137int 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*/
152int 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*/
176static 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*/
206static 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*/
266static 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*/
287void 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*/
330void 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*/
378static 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*/
412static 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*/
429static 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*/
446static 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*/
463static 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*/
479static 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*/
501static 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*/
523static 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*/
535int 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*/
545static 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*/
557int 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*/
568int 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 */
622static 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*/
636void 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*/
681void 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*/
716lua_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*/
736lua_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*/
754lua_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
769lua_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*/
785static 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*/
806void 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
1126void 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