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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 lua_assert(total >= 2);
638 do {
639 StkId top = L->top;
640 int n = 2; /* number of elements handled in this pass (at least 2) */
641 if (!(ttisstring(s2v(top - 2)) || cvt2str(s2v(top - 2))) ||
642 !tostring(L, s2v(top - 1)))
643 luaT_tryconcatTM(L);
644 else if (isemptystr(s2v(top - 1))) /* second operand is empty? */
645 cast_void(tostring(L, s2v(top - 2))); /* result is first operand */
646 else if (isemptystr(s2v(top - 2))) { /* first operand is empty string? */
647 setobjs2s(L, top - 2, top - 1); /* result is second op. */
648 }
649 else {
650 /* at least two non-empty string values; get as many as possible */
651 size_t tl = vslen(s2v(top - 1));
652 TString *ts;
653 /* collect total length and number of strings */
654 for (n = 1; n < total && tostring(L, s2v(top - n - 1)); n++) {
655 size_t l = vslen(s2v(top - n - 1));
656 if (unlikely(l >= (MAX_SIZE/sizeof(char)) - tl))
657 luaG_runerror(L, "string length overflow");
658 tl += l;
659 }
660 if (tl <= LUAI_MAXSHORTLEN) { /* is result a short string? */
661 char buff[LUAI_MAXSHORTLEN];
662 copy2buff(top, n, buff); /* copy strings to buffer */
663 ts = luaS_newlstr(L, buff, tl);
664 }
665 else { /* long string; copy strings directly to final result */
666 ts = luaS_createlngstrobj(L, tl);
667 copy2buff(top, n, getstr(ts));
668 }
669 setsvalue2s(L, top - n, ts); /* create result */
670 }
671 total -= n-1; /* got 'n' strings to create 1 new */
672 L->top -= n-1; /* popped 'n' strings and pushed one */
673 } while (total > 1); /* repeat until only 1 result left */
674}
675
676
677/*
678** Main operation 'ra = #rb'.
679*/
680void luaV_objlen (lua_State *L, StkId ra, const TValue *rb) {
681 const TValue *tm;
682 switch (ttypetag(rb)) {
683 case LUA_VTABLE: {
684 Table *h = hvalue(rb);
685 tm = fasttm(L, h->metatable, TM_LEN);
686 if (tm) break; /* metamethod? break switch to call it */
687 setivalue(s2v(ra), luaH_getn(h)); /* else primitive len */
688 return;
689 }
690 case LUA_VSHRSTR: {
691 setivalue(s2v(ra), tsvalue(rb)->shrlen);
692 return;
693 }
694 case LUA_VLNGSTR: {
695 setivalue(s2v(ra), tsvalue(rb)->u.lnglen);
696 return;
697 }
698 default: { /* try metamethod */
699 tm = luaT_gettmbyobj(L, rb, TM_LEN);
700 if (unlikely(notm(tm))) /* no metamethod? */
701 luaG_typeerror(L, rb, "get length of");
702 break;
703 }
704 }
705 luaT_callTMres(L, tm, rb, rb, ra);
706}
707
708
709/*
710** Integer division; return 'm // n', that is, floor(m/n).
711** C division truncates its result (rounds towards zero).
712** 'floor(q) == trunc(q)' when 'q >= 0' or when 'q' is integer,
713** otherwise 'floor(q) == trunc(q) - 1'.
714*/
715lua_Integer luaV_idiv (lua_State *L, lua_Integer m, lua_Integer n) {
716 if (unlikely(l_castS2U(n) + 1u <= 1u)) { /* special cases: -1 or 0 */
717 if (n == 0)
718 luaG_runerror(L, "attempt to divide by zero");
719 return intop(-, 0, m); /* n==-1; avoid overflow with 0x80000...//-1 */
720 }
721 else {
722 lua_Integer q = m / n; /* perform C division */
723 if ((m ^ n) < 0 && m % n != 0) /* 'm/n' would be negative non-integer? */
724 q -= 1; /* correct result for different rounding */
725 return q;
726 }
727}
728
729
730/*
731** Integer modulus; return 'm % n'. (Assume that C '%' with
732** negative operands follows C99 behavior. See previous comment
733** about luaV_idiv.)
734*/
735lua_Integer luaV_mod (lua_State *L, lua_Integer m, lua_Integer n) {
736 if (unlikely(l_castS2U(n) + 1u <= 1u)) { /* special cases: -1 or 0 */
737 if (n == 0)
738 luaG_runerror(L, "attempt to perform 'n%%0'");
739 return 0; /* m % -1 == 0; avoid overflow with 0x80000...%-1 */
740 }
741 else {
742 lua_Integer r = m % n;
743 if (r != 0 && (r ^ n) < 0) /* 'm/n' would be non-integer negative? */
744 r += n; /* correct result for different rounding */
745 return r;
746 }
747}
748
749
750/*
751** Float modulus
752*/
753lua_Number luaV_modf (lua_State *L, lua_Number m, lua_Number n) {
754 lua_Number r;
755 luai_nummod(L, m, n, r);
756 return r;
757}
758
759
760/* number of bits in an integer */
761#define NBITS cast_int(sizeof(lua_Integer) * CHAR_BIT)
762
763/*
764** Shift left operation. (Shift right just negates 'y'.)
765*/
766#define luaV_shiftr(x,y) luaV_shiftl(x,-(y))
767
768lua_Integer luaV_shiftl (lua_Integer x, lua_Integer y) {
769 if (y < 0) { /* shift right? */
770 if (y <= -NBITS) return 0;
771 else return intop(>>, x, -y);
772 }
773 else { /* shift left */
774 if (y >= NBITS) return 0;
775 else return intop(<<, x, y);
776 }
777}
778
779
780/*
781** create a new Lua closure, push it in the stack, and initialize
782** its upvalues.
783*/
784static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base,
785 StkId ra) {
786 int nup = p->sizeupvalues;
787 Upvaldesc *uv = p->upvalues;
788 int i;
789 LClosure *ncl = luaF_newLclosure(L, nup);
790 ncl->p = p;
791 setclLvalue2s(L, ra, ncl); /* anchor new closure in stack */
792 for (i = 0; i < nup; i++) { /* fill in its upvalues */
793 if (uv[i].instack) /* upvalue refers to local variable? */
794 ncl->upvals[i] = luaF_findupval(L, base + uv[i].idx);
795 else /* get upvalue from enclosing function */
796 ncl->upvals[i] = encup[uv[i].idx];
797 luaC_objbarrier(L, ncl, ncl->upvals[i]);
798 }
799}
800
801
802/*
803** finish execution of an opcode interrupted by a yield
804*/
805void luaV_finishOp (lua_State *L) {
806 CallInfo *ci = L->ci;
807 StkId base = ci->func + 1;
808 Instruction inst = *(ci->u.l.savedpc - 1); /* interrupted instruction */
809 OpCode op = GET_OPCODE(inst);
810 switch (op) { /* finish its execution */
811 case OP_MMBIN: case OP_MMBINI: case OP_MMBINK: {
812 setobjs2s(L, base + GETARG_A(*(ci->u.l.savedpc - 2)), --L->top);
813 break;
814 }
815 case OP_UNM: case OP_BNOT: case OP_LEN:
816 case OP_GETTABUP: case OP_GETTABLE: case OP_GETI:
817 case OP_GETFIELD: case OP_SELF: {
818 setobjs2s(L, base + GETARG_A(inst), --L->top);
819 break;
820 }
821 case OP_LT: case OP_LE:
822 case OP_LTI: case OP_LEI:
823 case OP_GTI: case OP_GEI:
824 case OP_EQ: { /* note that 'OP_EQI'/'OP_EQK' cannot yield */
825 int res = !l_isfalse(s2v(L->top - 1));
826 L->top--;
827#if defined(LUA_COMPAT_LT_LE)
828 if (ci->callstatus & CIST_LEQ) { /* "<=" using "<" instead? */
829 ci->callstatus ^= CIST_LEQ; /* clear mark */
830 res = !res; /* negate result */
831 }
832#endif
833 lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_JMP);
834 if (res != GETARG_k(inst)) /* condition failed? */
835 ci->u.l.savedpc++; /* skip jump instruction */
836 break;
837 }
838 case OP_CONCAT: {
839 StkId top = L->top - 1; /* top when 'luaT_tryconcatTM' was called */
840 int a = GETARG_A(inst); /* first element to concatenate */
841 int total = cast_int(top - 1 - (base + a)); /* yet to concatenate */
842 setobjs2s(L, top - 2, top); /* put TM result in proper position */
843 if (total > 1) { /* are there elements to concat? */
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 }
847 break;
848 }
849 default: {
850 /* only these other opcodes can yield */
851 lua_assert(op == OP_TFORCALL || op == OP_CALL ||
852 op == OP_TAILCALL || op == OP_SETTABUP || op == OP_SETTABLE ||
853 op == OP_SETI || op == OP_SETFIELD);
854 break;
855 }
856 }
857}
858
859
860
861
862/*
863** {==================================================================
864** Macros for arithmetic/bitwise/comparison opcodes in 'luaV_execute'
865** ===================================================================
866*/
867
868#define l_addi(L,a,b) intop(+, a, b)
869#define l_subi(L,a,b) intop(-, a, b)
870#define l_muli(L,a,b) intop(*, a, b)
871#define l_band(a,b) intop(&, a, b)
872#define l_bor(a,b) intop(|, a, b)
873#define l_bxor(a,b) intop(^, a, b)
874
875#define l_lti(a,b) (a < b)
876#define l_lei(a,b) (a <= b)
877#define l_gti(a,b) (a > b)
878#define l_gei(a,b) (a >= b)
879
880
881/*
882** Arithmetic operations with immediate operands. 'iop' is the integer
883** operation, 'fop' is the float operation.
884*/
885#define op_arithI(L,iop,fop) { \
886 TValue *v1 = vRB(i); \
887 int imm = GETARG_sC(i); \
888 if (ttisinteger(v1)) { \
889 lua_Integer iv1 = ivalue(v1); \
890 pc++; setivalue(s2v(ra), iop(L, iv1, imm)); \
891 } \
892 else if (ttisfloat(v1)) { \
893 lua_Number nb = fltvalue(v1); \
894 lua_Number fimm = cast_num(imm); \
895 pc++; setfltvalue(s2v(ra), fop(L, nb, fimm)); \
896 }}
897
898
899/*
900** Auxiliary function for arithmetic operations over floats and others
901** with two register operands.
902*/
903#define op_arithf_aux(L,v1,v2,fop) { \
904 lua_Number n1; lua_Number n2; \
905 if (tonumberns(v1, n1) && tonumberns(v2, n2)) { \
906 pc++; setfltvalue(s2v(ra), fop(L, n1, n2)); \
907 }}
908
909
910/*
911** Arithmetic operations over floats and others with register operands.
912*/
913#define op_arithf(L,fop) { \
914 TValue *v1 = vRB(i); \
915 TValue *v2 = vRC(i); \
916 op_arithf_aux(L, v1, v2, fop); }
917
918
919/*
920** Arithmetic operations with K operands for floats.
921*/
922#define op_arithfK(L,fop) { \
923 TValue *v1 = vRB(i); \
924 TValue *v2 = KC(i); \
925 op_arithf_aux(L, v1, v2, fop); }
926
927
928/*
929** Arithmetic operations over integers and floats.
930*/
931#define op_arith_aux(L,v1,v2,iop,fop) { \
932 if (ttisinteger(v1) && ttisinteger(v2)) { \
933 lua_Integer i1 = ivalue(v1); lua_Integer i2 = ivalue(v2); \
934 pc++; setivalue(s2v(ra), iop(L, i1, i2)); \
935 } \
936 else op_arithf_aux(L, v1, v2, fop); }
937
938
939/*
940** Arithmetic operations with register operands.
941*/
942#define op_arith(L,iop,fop) { \
943 TValue *v1 = vRB(i); \
944 TValue *v2 = vRC(i); \
945 op_arith_aux(L, v1, v2, iop, fop); }
946
947
948/*
949** Arithmetic operations with K operands.
950*/
951#define op_arithK(L,iop,fop) { \
952 TValue *v1 = vRB(i); \
953 TValue *v2 = KC(i); \
954 op_arith_aux(L, v1, v2, iop, fop); }
955
956
957/*
958** Bitwise operations with constant operand.
959*/
960#define op_bitwiseK(L,op) { \
961 TValue *v1 = vRB(i); \
962 TValue *v2 = KC(i); \
963 lua_Integer i1; \
964 lua_Integer i2 = ivalue(v2); \
965 if (tointegerns(v1, &i1)) { \
966 pc++; setivalue(s2v(ra), op(i1, i2)); \
967 }}
968
969
970/*
971** Bitwise operations with register operands.
972*/
973#define op_bitwise(L,op) { \
974 TValue *v1 = vRB(i); \
975 TValue *v2 = vRC(i); \
976 lua_Integer i1; lua_Integer i2; \
977 if (tointegerns(v1, &i1) && tointegerns(v2, &i2)) { \
978 pc++; setivalue(s2v(ra), op(i1, i2)); \
979 }}
980
981
982/*
983** Order operations with register operands. 'opn' actually works
984** for all numbers, but the fast track improves performance for
985** integers.
986*/
987#define op_order(L,opi,opn,other) { \
988 int cond; \
989 TValue *rb = vRB(i); \
990 if (ttisinteger(s2v(ra)) && ttisinteger(rb)) { \
991 lua_Integer ia = ivalue(s2v(ra)); \
992 lua_Integer ib = ivalue(rb); \
993 cond = opi(ia, ib); \
994 } \
995 else if (ttisnumber(s2v(ra)) && ttisnumber(rb)) \
996 cond = opn(s2v(ra), rb); \
997 else \
998 Protect(cond = other(L, s2v(ra), rb)); \
999 docondjump(); }
1000
1001
1002/*
1003** Order operations with immediate operand. (Immediate operand is
1004** always small enough to have an exact representation as a float.)
1005*/
1006#define op_orderI(L,opi,opf,inv,tm) { \
1007 int cond; \
1008 int im = GETARG_sB(i); \
1009 if (ttisinteger(s2v(ra))) \
1010 cond = opi(ivalue(s2v(ra)), im); \
1011 else if (ttisfloat(s2v(ra))) { \
1012 lua_Number fa = fltvalue(s2v(ra)); \
1013 lua_Number fim = cast_num(im); \
1014 cond = opf(fa, fim); \
1015 } \
1016 else { \
1017 int isf = GETARG_C(i); \
1018 Protect(cond = luaT_callorderiTM(L, s2v(ra), im, inv, isf, tm)); \
1019 } \
1020 docondjump(); }
1021
1022/* }================================================================== */
1023
1024
1025/*
1026** {==================================================================
1027** Function 'luaV_execute': main interpreter loop
1028** ===================================================================
1029*/
1030
1031/*
1032** some macros for common tasks in 'luaV_execute'
1033*/
1034
1035
1036#define RA(i) (base+GETARG_A(i))
1037#define RB(i) (base+GETARG_B(i))
1038#define vRB(i) s2v(RB(i))
1039#define KB(i) (k+GETARG_B(i))
1040#define RC(i) (base+GETARG_C(i))
1041#define vRC(i) s2v(RC(i))
1042#define KC(i) (k+GETARG_C(i))
1043#define RKC(i) ((TESTARG_k(i)) ? k + GETARG_C(i) : s2v(base + GETARG_C(i)))
1044
1045
1046
1047#define updatetrap(ci) (trap = ci->u.l.trap)
1048
1049#define updatebase(ci) (base = ci->func + 1)
1050
1051
1052#define updatestack(ci) { if (trap) { updatebase(ci); ra = RA(i); } }
1053
1054
1055/*
1056** Execute a jump instruction. The 'updatetrap' allows signals to stop
1057** tight loops. (Without it, the local copy of 'trap' could never change.)
1058*/
1059#define dojump(ci,i,e) { pc += GETARG_sJ(i) + e; updatetrap(ci); }
1060
1061
1062/* for test instructions, execute the jump instruction that follows it */
1063#define donextjump(ci) { Instruction ni = *pc; dojump(ci, ni, 1); }
1064
1065/*
1066** do a conditional jump: skip next instruction if 'cond' is not what
1067** was expected (parameter 'k'), else do next instruction, which must
1068** be a jump.
1069*/
1070#define docondjump() if (cond != GETARG_k(i)) pc++; else donextjump(ci);
1071
1072
1073/*
1074** Correct global 'pc'.
1075*/
1076#define savepc(L) (ci->u.l.savedpc = pc)
1077
1078
1079/*
1080** Whenever code can raise errors, the global 'pc' and the global
1081** 'top' must be correct to report occasional errors.
1082*/
1083#define savestate(L,ci) (savepc(L), L->top = ci->top)
1084
1085
1086/*
1087** Protect code that, in general, can raise errors, reallocate the
1088** stack, and change the hooks.
1089*/
1090#define Protect(exp) (savestate(L,ci), (exp), updatetrap(ci))
1091
1092/* special version that does not change the top */
1093#define ProtectNT(exp) (savepc(L), (exp), updatetrap(ci))
1094
1095/*
1096** Protect code that will finish the loop (returns) or can only raise
1097** errors. (That is, it will not return to the interpreter main loop
1098** after changing the stack or hooks.)
1099*/
1100#define halfProtect(exp) (savestate(L,ci), (exp))
1101
1102/* idem, but without changing the stack */
1103#define halfProtectNT(exp) (savepc(L), (exp))
1104
1105
1106#define checkGC(L,c) \
1107 { luaC_condGC(L, L->top = (c), /* limit of live values */ \
1108 updatetrap(ci)); \
1109 luai_threadyield(L); }
1110
1111
1112/* fetch an instruction and prepare its execution */
1113#define vmfetch() { \
1114 if (trap) { /* stack reallocation or hooks? */ \
1115 trap = luaG_traceexec(L, pc); /* handle hooks */ \
1116 updatebase(ci); /* correct stack */ \
1117 } \
1118 i = *(pc++); \
1119 ra = RA(i); /* WARNING: any stack reallocation invalidates 'ra' */ \
1120}
1121
1122#define vmdispatch(o) switch(o)
1123#define vmcase(l) case l:
1124#define vmbreak break
1125
1126
1127void luaV_execute (lua_State *L, CallInfo *ci) {
1128 LClosure *cl;
1129 TValue *k;
1130 StkId base;
1131 const Instruction *pc;
1132 int trap;
1133#if LUA_USE_JUMPTABLE
1134#include "ljumptab.h"
1135#endif
1136 tailcall:
1137 trap = L->hookmask;
1138 cl = clLvalue(s2v(ci->func));
1139 k = cl->p->k;
1140 pc = ci->u.l.savedpc;
1141 if (trap) {
1142 if (cl->p->is_vararg)
1143 trap = 0; /* hooks will start after VARARGPREP instruction */
1144 else if (pc == cl->p->code) /* first instruction (not resuming)? */
1145 luaD_hookcall(L, ci);
1146 ci->u.l.trap = 1; /* there may be other hooks */
1147 }
1148 base = ci->func + 1;
1149 /* main loop of interpreter */
1150 for (;;) {
1151 Instruction i; /* instruction being executed */
1152 StkId ra; /* instruction's A register */
1153 vmfetch();
1154 lua_assert(base == ci->func + 1);
1155 lua_assert(base <= L->top && L->top < L->stack + L->stacksize);
1156 /* invalidate top for instructions not expecting it */
1157 lua_assert(isIT(i) || (cast_void(L->top = base), 1));
1158 vmdispatch (GET_OPCODE(i)) {
1159 vmcase(OP_MOVE) {
1160 setobjs2s(L, ra, RB(i));
1161 vmbreak;
1162 }
1163 vmcase(OP_LOADI) {
1164 lua_Integer b = GETARG_sBx(i);
1165 setivalue(s2v(ra), b);
1166 vmbreak;
1167 }
1168 vmcase(OP_LOADF) {
1169 int b = GETARG_sBx(i);
1170 setfltvalue(s2v(ra), cast_num(b));
1171 vmbreak;
1172 }
1173 vmcase(OP_LOADK) {
1174 TValue *rb = k + GETARG_Bx(i);
1175 setobj2s(L, ra, rb);
1176 vmbreak;
1177 }
1178 vmcase(OP_LOADKX) {
1179 TValue *rb;
1180 rb = k + GETARG_Ax(*pc); pc++;
1181 setobj2s(L, ra, rb);
1182 vmbreak;
1183 }
1184 vmcase(OP_LOADFALSE) {
1185 setbfvalue(s2v(ra));
1186 vmbreak;
1187 }
1188 vmcase(OP_LFALSESKIP) {
1189 setbfvalue(s2v(ra));
1190 pc++; /* skip next instruction */
1191 vmbreak;
1192 }
1193 vmcase(OP_LOADTRUE) {
1194 setbtvalue(s2v(ra));
1195 vmbreak;
1196 }
1197 vmcase(OP_LOADNIL) {
1198 int b = GETARG_B(i);
1199 do {
1200 setnilvalue(s2v(ra++));
1201 } while (b--);
1202 vmbreak;
1203 }
1204 vmcase(OP_GETUPVAL) {
1205 int b = GETARG_B(i);
1206 setobj2s(L, ra, cl->upvals[b]->v);
1207 vmbreak;
1208 }
1209 vmcase(OP_SETUPVAL) {
1210 UpVal *uv = cl->upvals[GETARG_B(i)];
1211 setobj(L, uv->v, s2v(ra));
1212 luaC_barrier(L, uv, s2v(ra));
1213 vmbreak;
1214 }
1215 vmcase(OP_GETTABUP) {
1216 const TValue *slot;
1217 TValue *upval = cl->upvals[GETARG_B(i)]->v;
1218 TValue *rc = KC(i);
1219 TString *key = tsvalue(rc); /* key must be a string */
1220 if (luaV_fastget(L, upval, key, slot, luaH_getshortstr)) {
1221 setobj2s(L, ra, slot);
1222 }
1223 else
1224 Protect(luaV_finishget(L, upval, rc, ra, slot));
1225 vmbreak;
1226 }
1227 vmcase(OP_GETTABLE) {
1228 const TValue *slot;
1229 TValue *rb = vRB(i);
1230 TValue *rc = vRC(i);
1231 lua_Unsigned n;
1232 if (ttisinteger(rc) /* fast track for integers? */
1233 ? (cast_void(n = ivalue(rc)), luaV_fastgeti(L, rb, n, slot))
1234 : luaV_fastget(L, rb, rc, slot, luaH_get)) {
1235 setobj2s(L, ra, slot);
1236 }
1237 else
1238 Protect(luaV_finishget(L, rb, rc, ra, slot));
1239 vmbreak;
1240 }
1241 vmcase(OP_GETI) {
1242 const TValue *slot;
1243 TValue *rb = vRB(i);
1244 int c = GETARG_C(i);
1245 if (luaV_fastgeti(L, rb, c, slot)) {
1246 setobj2s(L, ra, slot);
1247 }
1248 else {
1249 TValue key;
1250 setivalue(&key, c);
1251 Protect(luaV_finishget(L, rb, &key, ra, slot));
1252 }
1253 vmbreak;
1254 }
1255 vmcase(OP_GETFIELD) {
1256 const TValue *slot;
1257 TValue *rb = vRB(i);
1258 TValue *rc = KC(i);
1259 TString *key = tsvalue(rc); /* key must be a string */
1260 if (luaV_fastget(L, rb, key, slot, luaH_getshortstr)) {
1261 setobj2s(L, ra, slot);
1262 }
1263 else
1264 Protect(luaV_finishget(L, rb, rc, ra, slot));
1265 vmbreak;
1266 }
1267 vmcase(OP_SETTABUP) {
1268 const TValue *slot;
1269 TValue *upval = cl->upvals[GETARG_A(i)]->v;
1270 TValue *rb = KB(i);
1271 TValue *rc = RKC(i);
1272 TString *key = tsvalue(rb); /* key must be a string */
1273 if (luaV_fastget(L, upval, key, slot, luaH_getshortstr)) {
1274 luaV_finishfastset(L, upval, slot, rc);
1275 }
1276 else
1277 Protect(luaV_finishset(L, upval, rb, rc, slot));
1278 vmbreak;
1279 }
1280 vmcase(OP_SETTABLE) {
1281 const TValue *slot;
1282 TValue *rb = vRB(i); /* key (table is in 'ra') */
1283 TValue *rc = RKC(i); /* value */
1284 lua_Unsigned n;
1285 if (ttisinteger(rb) /* fast track for integers? */
1286 ? (cast_void(n = ivalue(rb)), luaV_fastgeti(L, s2v(ra), n, slot))
1287 : luaV_fastget(L, s2v(ra), rb, slot, luaH_get)) {
1288 luaV_finishfastset(L, s2v(ra), slot, rc);
1289 }
1290 else
1291 Protect(luaV_finishset(L, s2v(ra), rb, rc, slot));
1292 vmbreak;
1293 }
1294 vmcase(OP_SETI) {
1295 const TValue *slot;
1296 int c = GETARG_B(i);
1297 TValue *rc = RKC(i);
1298 if (luaV_fastgeti(L, s2v(ra), c, slot)) {
1299 luaV_finishfastset(L, s2v(ra), slot, rc);
1300 }
1301 else {
1302 TValue key;
1303 setivalue(&key, c);
1304 Protect(luaV_finishset(L, s2v(ra), &key, rc, slot));
1305 }
1306 vmbreak;
1307 }
1308 vmcase(OP_SETFIELD) {
1309 const TValue *slot;
1310 TValue *rb = KB(i);
1311 TValue *rc = RKC(i);
1312 TString *key = tsvalue(rb); /* key must be a string */
1313 if (luaV_fastget(L, s2v(ra), key, slot, luaH_getshortstr)) {
1314 luaV_finishfastset(L, s2v(ra), slot, rc);
1315 }
1316 else
1317 Protect(luaV_finishset(L, s2v(ra), rb, rc, slot));
1318 vmbreak;
1319 }
1320 vmcase(OP_NEWTABLE) {
1321 int b = GETARG_B(i); /* log2(hash size) + 1 */
1322 int c = GETARG_C(i); /* array size */
1323 Table *t;
1324 if (b > 0)
1325 b = 1 << (b - 1); /* size is 2^(b - 1) */
1326 lua_assert((!TESTARG_k(i)) == (GETARG_Ax(*pc) == 0));
1327 if (TESTARG_k(i)) /* non-zero extra argument? */
1328 c += GETARG_Ax(*pc) * (MAXARG_C + 1); /* add it to size */
1329 pc++; /* skip extra argument */
1330 L->top = ra + 1; /* correct top in case of emergency GC */
1331 t = luaH_new(L); /* memory allocation */
1332 sethvalue2s(L, ra, t);
1333 if (b != 0 || c != 0)
1334 luaH_resize(L, t, c, b); /* idem */
1335 checkGC(L, ra + 1);
1336 vmbreak;
1337 }
1338 vmcase(OP_SELF) {
1339 const TValue *slot;
1340 TValue *rb = vRB(i);
1341 TValue *rc = RKC(i);
1342 TString *key = tsvalue(rc); /* key must be a string */
1343 setobj2s(L, ra + 1, rb);
1344 if (luaV_fastget(L, rb, key, slot, luaH_getstr)) {
1345 setobj2s(L, ra, slot);
1346 }
1347 else
1348 Protect(luaV_finishget(L, rb, rc, ra, slot));
1349 vmbreak;
1350 }
1351 vmcase(OP_ADDI) {
1352 op_arithI(L, l_addi, luai_numadd);
1353 vmbreak;
1354 }
1355 vmcase(OP_ADDK) {
1356 op_arithK(L, l_addi, luai_numadd);
1357 vmbreak;
1358 }
1359 vmcase(OP_SUBK) {
1360 op_arithK(L, l_subi, luai_numsub);
1361 vmbreak;
1362 }
1363 vmcase(OP_MULK) {
1364 op_arithK(L, l_muli, luai_nummul);
1365 vmbreak;
1366 }
1367 vmcase(OP_MODK) {
1368 op_arithK(L, luaV_mod, luaV_modf);
1369 vmbreak;
1370 }
1371 vmcase(OP_POWK) {
1372 op_arithfK(L, luai_numpow);
1373 vmbreak;
1374 }
1375 vmcase(OP_DIVK) {
1376 op_arithfK(L, luai_numdiv);
1377 vmbreak;
1378 }
1379 vmcase(OP_IDIVK) {
1380 op_arithK(L, luaV_idiv, luai_numidiv);
1381 vmbreak;
1382 }
1383 vmcase(OP_BANDK) {
1384 op_bitwiseK(L, l_band);
1385 vmbreak;
1386 }
1387 vmcase(OP_BORK) {
1388 op_bitwiseK(L, l_bor);
1389 vmbreak;
1390 }
1391 vmcase(OP_BXORK) {
1392 op_bitwiseK(L, l_bxor);
1393 vmbreak;
1394 }
1395 vmcase(OP_SHRI) {
1396 TValue *rb = vRB(i);
1397 int ic = GETARG_sC(i);
1398 lua_Integer ib;
1399 if (tointegerns(rb, &ib)) {
1400 pc++; setivalue(s2v(ra), luaV_shiftl(ib, -ic));
1401 }
1402 vmbreak;
1403 }
1404 vmcase(OP_SHLI) {
1405 TValue *rb = vRB(i);
1406 int ic = GETARG_sC(i);
1407 lua_Integer ib;
1408 if (tointegerns(rb, &ib)) {
1409 pc++; setivalue(s2v(ra), luaV_shiftl(ic, ib));
1410 }
1411 vmbreak;
1412 }
1413 vmcase(OP_ADD) {
1414 op_arith(L, l_addi, luai_numadd);
1415 vmbreak;
1416 }
1417 vmcase(OP_SUB) {
1418 op_arith(L, l_subi, luai_numsub);
1419 vmbreak;
1420 }
1421 vmcase(OP_MUL) {
1422 op_arith(L, l_muli, luai_nummul);
1423 vmbreak;
1424 }
1425 vmcase(OP_MOD) {
1426 op_arith(L, luaV_mod, luaV_modf);
1427 vmbreak;
1428 }
1429 vmcase(OP_POW) {
1430 op_arithf(L, luai_numpow);
1431 vmbreak;
1432 }
1433 vmcase(OP_DIV) { /* float division (always with floats) */
1434 op_arithf(L, luai_numdiv);
1435 vmbreak;
1436 }
1437 vmcase(OP_IDIV) { /* floor division */
1438 op_arith(L, luaV_idiv, luai_numidiv);
1439 vmbreak;
1440 }
1441 vmcase(OP_BAND) {
1442 op_bitwise(L, l_band);
1443 vmbreak;
1444 }
1445 vmcase(OP_BOR) {
1446 op_bitwise(L, l_bor);
1447 vmbreak;
1448 }
1449 vmcase(OP_BXOR) {
1450 op_bitwise(L, l_bxor);
1451 vmbreak;
1452 }
1453 vmcase(OP_SHR) {
1454 op_bitwise(L, luaV_shiftr);
1455 vmbreak;
1456 }
1457 vmcase(OP_SHL) {
1458 op_bitwise(L, luaV_shiftl);
1459 vmbreak;
1460 }
1461 vmcase(OP_MMBIN) {
1462 Instruction pi = *(pc - 2); /* original arith. expression */
1463 TValue *rb = vRB(i);
1464 TMS tm = (TMS)GETARG_C(i);
1465 StkId result = RA(pi);
1466 lua_assert(OP_ADD <= GET_OPCODE(pi) && GET_OPCODE(pi) <= OP_SHR);
1467 Protect(luaT_trybinTM(L, s2v(ra), rb, result, tm));
1468 vmbreak;
1469 }
1470 vmcase(OP_MMBINI) {
1471 Instruction pi = *(pc - 2); /* original arith. expression */
1472 int imm = GETARG_sB(i);
1473 TMS tm = (TMS)GETARG_C(i);
1474 int flip = GETARG_k(i);
1475 StkId result = RA(pi);
1476 Protect(luaT_trybiniTM(L, s2v(ra), imm, flip, result, tm));
1477 vmbreak;
1478 }
1479 vmcase(OP_MMBINK) {
1480 Instruction pi = *(pc - 2); /* original arith. expression */
1481 TValue *imm = KB(i);
1482 TMS tm = (TMS)GETARG_C(i);
1483 int flip = GETARG_k(i);
1484 StkId result = RA(pi);
1485 Protect(luaT_trybinassocTM(L, s2v(ra), imm, flip, result, tm));
1486 vmbreak;
1487 }
1488 vmcase(OP_UNM) {
1489 TValue *rb = vRB(i);
1490 lua_Number nb;
1491 if (ttisinteger(rb)) {
1492 lua_Integer ib = ivalue(rb);
1493 setivalue(s2v(ra), intop(-, 0, ib));
1494 }
1495 else if (tonumberns(rb, nb)) {
1496 setfltvalue(s2v(ra), luai_numunm(L, nb));
1497 }
1498 else
1499 Protect(luaT_trybinTM(L, rb, rb, ra, TM_UNM));
1500 vmbreak;
1501 }
1502 vmcase(OP_BNOT) {
1503 TValue *rb = vRB(i);
1504 lua_Integer ib;
1505 if (tointegerns(rb, &ib)) {
1506 setivalue(s2v(ra), intop(^, ~l_castS2U(0), ib));
1507 }
1508 else
1509 Protect(luaT_trybinTM(L, rb, rb, ra, TM_BNOT));
1510 vmbreak;
1511 }
1512 vmcase(OP_NOT) {
1513 TValue *rb = vRB(i);
1514 if (l_isfalse(rb))
1515 setbtvalue(s2v(ra));
1516 else
1517 setbfvalue(s2v(ra));
1518 vmbreak;
1519 }
1520 vmcase(OP_LEN) {
1521 Protect(luaV_objlen(L, ra, vRB(i)));
1522 vmbreak;
1523 }
1524 vmcase(OP_CONCAT) {
1525 int n = GETARG_B(i); /* number of elements to concatenate */
1526 L->top = ra + n; /* mark the end of concat operands */
1527 ProtectNT(luaV_concat(L, n));
1528 checkGC(L, L->top); /* 'luaV_concat' ensures correct top */
1529 vmbreak;
1530 }
1531 vmcase(OP_CLOSE) {
1532 Protect(luaF_close(L, ra, LUA_OK));
1533 vmbreak;
1534 }
1535 vmcase(OP_TBC) {
1536 /* create new to-be-closed upvalue */
1537 halfProtect(luaF_newtbcupval(L, ra));
1538 vmbreak;
1539 }
1540 vmcase(OP_JMP) {
1541 dojump(ci, i, 0);
1542 vmbreak;
1543 }
1544 vmcase(OP_EQ) {
1545 int cond;
1546 TValue *rb = vRB(i);
1547 Protect(cond = luaV_equalobj(L, s2v(ra), rb));
1548 docondjump();
1549 vmbreak;
1550 }
1551 vmcase(OP_LT) {
1552 op_order(L, l_lti, LTnum, lessthanothers);
1553 vmbreak;
1554 }
1555 vmcase(OP_LE) {
1556 op_order(L, l_lei, LEnum, lessequalothers);
1557 vmbreak;
1558 }
1559 vmcase(OP_EQK) {
1560 TValue *rb = KB(i);
1561 /* basic types do not use '__eq'; we can use raw equality */
1562 int cond = luaV_rawequalobj(s2v(ra), rb);
1563 docondjump();
1564 vmbreak;
1565 }
1566 vmcase(OP_EQI) {
1567 int cond;
1568 int im = GETARG_sB(i);
1569 if (ttisinteger(s2v(ra)))
1570 cond = (ivalue(s2v(ra)) == im);
1571 else if (ttisfloat(s2v(ra)))
1572 cond = luai_numeq(fltvalue(s2v(ra)), cast_num(im));
1573 else
1574 cond = 0; /* other types cannot be equal to a number */
1575 docondjump();
1576 vmbreak;
1577 }
1578 vmcase(OP_LTI) {
1579 op_orderI(L, l_lti, luai_numlt, 0, TM_LT);
1580 vmbreak;
1581 }
1582 vmcase(OP_LEI) {
1583 op_orderI(L, l_lei, luai_numle, 0, TM_LE);
1584 vmbreak;
1585 }
1586 vmcase(OP_GTI) {
1587 op_orderI(L, l_gti, luai_numgt, 1, TM_LT);
1588 vmbreak;
1589 }
1590 vmcase(OP_GEI) {
1591 op_orderI(L, l_gei, luai_numge, 1, TM_LE);
1592 vmbreak;
1593 }
1594 vmcase(OP_TEST) {
1595 int cond = !l_isfalse(s2v(ra));
1596 docondjump();
1597 vmbreak;
1598 }
1599 vmcase(OP_TESTSET) {
1600 TValue *rb = vRB(i);
1601 if (l_isfalse(rb) == GETARG_k(i))
1602 pc++;
1603 else {
1604 setobj2s(L, ra, rb);
1605 donextjump(ci);
1606 }
1607 vmbreak;
1608 }
1609 vmcase(OP_CALL) {
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 ProtectNT(luaD_call(L, ra, nresults));
1616 vmbreak;
1617 }
1618 vmcase(OP_TAILCALL) {
1619 int b = GETARG_B(i); /* number of arguments + 1 (function) */
1620 int nparams1 = GETARG_C(i);
1621 /* delat is virtual 'func' - real 'func' (vararg functions) */
1622 int delta = (nparams1) ? ci->u.l.nextraargs + nparams1 : 0;
1623 if (b != 0)
1624 L->top = ra + b;
1625 else /* previous instruction set top */
1626 b = cast_int(L->top - ra);
1627 savepc(ci); /* some calls here can raise errors */
1628 if (TESTARG_k(i)) {
1629 /* close upvalues from current call; the compiler ensures
1630 that there are no to-be-closed variables here, so this
1631 call cannot change the stack */
1632 luaF_close(L, base, NOCLOSINGMETH);
1633 lua_assert(base == ci->func + 1);
1634 }
1635 while (!ttisfunction(s2v(ra))) { /* not a function? */
1636 luaD_tryfuncTM(L, ra); /* try '__call' metamethod */
1637 b++; /* there is now one extra argument */
1638 checkstackp(L, 1, ra);
1639 }
1640 if (!ttisLclosure(s2v(ra))) { /* C function? */
1641 luaD_call(L, ra, LUA_MULTRET); /* call it */
1642 updatetrap(ci);
1643 updatestack(ci); /* stack may have been relocated */
1644 ci->func -= delta;
1645 luaD_poscall(L, ci, cast_int(L->top - ra));
1646 return;
1647 }
1648 ci->func -= delta;
1649 luaD_pretailcall(L, ci, ra, b); /* prepare call frame */
1650 goto tailcall;
1651 }
1652 vmcase(OP_RETURN) {
1653 int n = GETARG_B(i) - 1; /* number of results */
1654 int nparams1 = GETARG_C(i);
1655 if (n < 0) /* not fixed? */
1656 n = cast_int(L->top - ra); /* get what is available */
1657 savepc(ci);
1658 if (TESTARG_k(i)) { /* may there be open upvalues? */
1659 if (L->top < ci->top)
1660 L->top = ci->top;
1661 luaF_close(L, base, LUA_OK);
1662 updatetrap(ci);
1663 updatestack(ci);
1664 }
1665 if (nparams1) /* vararg function? */
1666 ci->func -= ci->u.l.nextraargs + nparams1;
1667 L->top = ra + n; /* set call for 'luaD_poscall' */
1668 luaD_poscall(L, ci, n);
1669 return;
1670 }
1671 vmcase(OP_RETURN0) {
1672 if (L->hookmask) {
1673 L->top = ra;
1674 halfProtectNT(luaD_poscall(L, ci, 0)); /* no hurry... */
1675 }
1676 else { /* do the 'poscall' here */
1677 int nres = ci->nresults;
1678 L->ci = ci->previous; /* back to caller */
1679 L->top = base - 1;
1680 while (nres-- > 0)
1681 setnilvalue(s2v(L->top++)); /* all results are nil */
1682 }
1683 return;
1684 }
1685 vmcase(OP_RETURN1) {
1686 if (L->hookmask) {
1687 L->top = ra + 1;
1688 halfProtectNT(luaD_poscall(L, ci, 1)); /* no hurry... */
1689 }
1690 else { /* do the 'poscall' here */
1691 int nres = ci->nresults;
1692 L->ci = ci->previous; /* back to caller */
1693 if (nres == 0)
1694 L->top = base - 1; /* asked for no results */
1695 else {
1696 setobjs2s(L, base - 1, ra); /* at least this result */
1697 L->top = base;
1698 while (--nres > 0) /* complete missing results */
1699 setnilvalue(s2v(L->top++));
1700 }
1701 }
1702 return;
1703 }
1704 vmcase(OP_FORLOOP) {
1705 if (ttisinteger(s2v(ra + 2))) { /* integer loop? */
1706 lua_Unsigned count = l_castS2U(ivalue(s2v(ra + 1)));
1707 if (count > 0) { /* still more iterations? */
1708 lua_Integer step = ivalue(s2v(ra + 2));
1709 lua_Integer idx = ivalue(s2v(ra)); /* internal index */
1710 chgivalue(s2v(ra + 1), count - 1); /* update counter */
1711 idx = intop(+, idx, step); /* add step to index */
1712 chgivalue(s2v(ra), idx); /* update internal index */
1713 setivalue(s2v(ra + 3), idx); /* and control variable */
1714 pc -= GETARG_Bx(i); /* jump back */
1715 }
1716 }
1717 else if (floatforloop(ra)) /* float loop */
1718 pc -= GETARG_Bx(i); /* jump back */
1719 updatetrap(ci); /* allows a signal to break the loop */
1720 vmbreak;
1721 }
1722 vmcase(OP_FORPREP) {
1723 savestate(L, ci); /* in case of errors */
1724 if (forprep(L, ra))
1725 pc += GETARG_Bx(i) + 1; /* skip the loop */
1726 vmbreak;
1727 }
1728 vmcase(OP_TFORPREP) {
1729 /* create to-be-closed upvalue (if needed) */
1730 halfProtect(luaF_newtbcupval(L, ra + 3));
1731 pc += GETARG_Bx(i);
1732 i = *(pc++); /* go to next instruction */
1733 lua_assert(GET_OPCODE(i) == OP_TFORCALL && ra == RA(i));
1734 goto l_tforcall;
1735 }
1736 vmcase(OP_TFORCALL) {
1737 l_tforcall:
1738 /* 'ra' has the iterator function, 'ra + 1' has the state,
1739 'ra + 2' has the control variable, and 'ra + 3' has the
1740 to-be-closed variable. The call will use the stack after
1741 these values (starting at 'ra + 4')
1742 */
1743 /* push function, state, and control variable */
1744 memcpy(ra + 4, ra, 3 * sizeof(*ra));
1745 L->top = ra + 4 + 3;
1746 ProtectNT(luaD_call(L, ra + 4, GETARG_C(i))); /* do the call */
1747 updatestack(ci); /* stack may have changed */
1748 i = *(pc++); /* go to next instruction */
1749 lua_assert(GET_OPCODE(i) == OP_TFORLOOP && ra == RA(i));
1750 goto l_tforloop;
1751 }
1752 vmcase(OP_TFORLOOP) {
1753 l_tforloop:
1754 if (!ttisnil(s2v(ra + 4))) { /* continue loop? */
1755 setobjs2s(L, ra + 2, ra + 4); /* save control variable */
1756 pc -= GETARG_Bx(i); /* jump back */
1757 }
1758 vmbreak;
1759 }
1760 vmcase(OP_SETLIST) {
1761 int n = GETARG_B(i);
1762 unsigned int last = GETARG_C(i);
1763 Table *h = hvalue(s2v(ra));
1764 if (n == 0)
1765 n = cast_int(L->top - ra) - 1; /* get up to the top */
1766 else
1767 L->top = ci->top; /* correct top in case of emergency GC */
1768 last += n;
1769 if (TESTARG_k(i)) {
1770 last += GETARG_Ax(*pc) * (MAXARG_C + 1);
1771 pc++;
1772 }
1773 if (last > luaH_realasize(h)) /* needs more space? */
1774 luaH_resizearray(L, h, last); /* preallocate it at once */
1775 for (; n > 0; n--) {
1776 TValue *val = s2v(ra + n);
1777 setobj2t(L, &h->array[last - 1], val);
1778 last--;
1779 luaC_barrierback(L, obj2gco(h), val);
1780 }
1781 vmbreak;
1782 }
1783 vmcase(OP_CLOSURE) {
1784 Proto *p = cl->p->p[GETARG_Bx(i)];
1785 halfProtect(pushclosure(L, p, cl->upvals, base, ra));
1786 checkGC(L, ra + 1);
1787 vmbreak;
1788 }
1789 vmcase(OP_VARARG) {
1790 int n = GETARG_C(i) - 1; /* required results */
1791 Protect(luaT_getvarargs(L, ci, ra, n));
1792 vmbreak;
1793 }
1794 vmcase(OP_VARARGPREP) {
1795 luaT_adjustvarargs(L, GETARG_A(i), ci, cl->p);
1796 updatetrap(ci);
1797 if (trap) {
1798 luaD_hookcall(L, ci);
1799 L->oldpc = pc + 1; /* next opcode will be seen as a "new" line */
1800 }
1801 updatebase(ci); /* function has new base after adjustment */
1802 vmbreak;
1803 }
1804 vmcase(OP_EXTRAARG) {
1805 lua_assert(0);
1806 vmbreak;
1807 }
1808 }
1809 }
1810}
1811
1812/* }================================================================== */