1 /* $NetBSD: lvm.c,v 1.7 2015/10/08 13:40:16 mbalmer Exp $ */
4 ** Id: lvm.c,v 2.245 2015/06/09 15:53:35 roberto Exp
6 ** See Copyright Notice in lua.h
38 /* limit for table tag-method chains (to avoid loops) */
39 #define MAXTAGLOOP 2000
44 ** 'l_intfitsf' checks whether a given integer can be converted to a
45 ** float without rounding. Used in comparisons. Left undefined if
46 ** all integers fit in a float precisely.
48 #if !defined(l_intfitsf)
50 /* number of bits in the mantissa of a float */
51 #define NBM (l_mathlim(MANT_DIG))
54 ** Check whether some integers may not fit in a float, that is, whether
55 ** (maxinteger >> NBM) > 0 (that implies (1 << NBM) <= maxinteger).
56 ** (The shifts are done in parts to avoid shifting by more than the size
57 ** of an integer. In a worst case, NBM == 113 for long double and
58 ** sizeof(integer) == 32.)
60 #if ((((LUA_MAXINTEGER >> (NBM / 4)) >> (NBM / 4)) >> (NBM / 4)) \
61 >> (NBM - (3 * (NBM / 4)))) > 0
63 #define l_intfitsf(i) \
64 (-((lua_Integer)1 << NBM) <= (i) && (i) <= ((lua_Integer)1 << NBM))
73 ** Try to convert a value to a float. The float case is already handled
74 ** by the macro 'tonumber'.
76 int luaV_tonumber_ (const TValue
*obj
, lua_Number
*n
) {
78 if (ttisinteger(obj
)) {
79 *n
= cast_num(ivalue(obj
));
82 else if (cvt2num(obj
) && /* string convertible to number? */
83 luaO_str2num(svalue(obj
), &v
) == vslen(obj
) + 1) {
84 *n
= nvalue(&v
); /* convert result of 'luaO_str2num' to a float */
88 return 0; /* conversion failed */
94 ** try to convert a value to an integer, rounding according to 'mode':
95 ** mode == 0: accepts only integral values
96 ** mode == 1: takes the floor of the number
97 ** mode == 2: takes the ceil of the number
99 int luaV_tointeger (const TValue
*obj
, lua_Integer
*p
, int mode
) {
103 if (ttisfloat(obj
)) {
104 lua_Number n
= fltvalue(obj
);
105 lua_Number f
= l_floor(n
);
106 if (n
!= f
) { /* not an integral value? */
107 if (mode
== 0) return 0; /* fails if mode demands integral value */
108 else if (mode
> 1) /* needs ceil? */
109 f
+= 1; /* convert floor to ceil (remember: n != f) */
111 return lua_numbertointeger(f
, p
);
113 else if (ttisinteger(obj
)) {
115 if (ttisinteger(obj
)) {
121 else if (cvt2num(obj
) &&
122 luaO_str2num(svalue(obj
), &v
) == vslen(obj
) + 1) {
124 goto again
; /* convert result from 'luaO_str2num' to an integer */
126 return 0; /* conversion failed */
132 ** Try to convert a 'for' limit to an integer, preserving the
133 ** semantics of the loop.
134 ** (The following explanation assumes a non-negative step; it is valid
135 ** for negative steps mutatis mutandis.)
136 ** If the limit can be converted to an integer, rounding down, that is
138 ** Otherwise, check whether the limit can be converted to a number. If
139 ** the number is too large, it is OK to set the limit as LUA_MAXINTEGER,
140 ** which means no limit. If the number is too negative, the loop
141 ** should not run, because any initial integer value is larger than the
142 ** limit. So, it sets the limit to LUA_MININTEGER. 'stopnow' corrects
143 ** the extreme case when the initial value is LUA_MININTEGER, in which
144 ** case the LUA_MININTEGER limit would still run the loop once.
146 static int forlimit (const TValue
*obj
, lua_Integer
*p
, lua_Integer step
,
148 *stopnow
= 0; /* usually, let loops run */
149 if (!luaV_tointeger(obj
, p
, (step
< 0 ? 2 : 1))) { /* not fit in integer? */
150 lua_Number n
; /* try to convert to float */
151 if (!tonumber(obj
, &n
)) /* cannot convert to float? */
152 return 0; /* not a number */
153 if (luai_numlt(0, n
)) { /* if true, float is larger than max integer */
155 if (step
< 0) *stopnow
= 1;
157 else { /* float is smaller than min integer */
159 if (step
>= 0) *stopnow
= 1;
168 ** Main function for table access (invoking metamethods if needed).
169 ** Compute 'val = t[key]'
171 void luaV_gettable (lua_State
*L
, const TValue
*t
, TValue
*key
, StkId val
) {
172 int loop
; /* counter to avoid infinite loops */
173 for (loop
= 0; loop
< MAXTAGLOOP
; loop
++) {
175 if (ttistable(t
)) { /* 't' is a table? */
176 Table
*h
= hvalue(t
);
177 const TValue
*res
= luaH_get(h
, key
); /* do a primitive get */
178 if (!ttisnil(res
) || /* result is not nil? */
179 (tm
= fasttm(L
, h
->metatable
, TM_INDEX
)) == NULL
) { /* or no TM? */
180 setobj2s(L
, val
, res
); /* result is the raw get */
183 /* else will try metamethod */
185 else if (ttisnil(tm
= luaT_gettmbyobj(L
, t
, TM_INDEX
)))
186 luaG_typeerror(L
, t
, "index"); /* no metamethod */
187 if (ttisfunction(tm
)) { /* metamethod is a function */
188 luaT_callTM(L
, tm
, t
, key
, val
, 1);
191 t
= tm
; /* else repeat access over 'tm' */
193 luaG_runerror(L
, "gettable chain too long; possible loop");
198 ** Main function for table assignment (invoking metamethods if needed).
199 ** Compute 't[key] = val'
201 void luaV_settable (lua_State
*L
, const TValue
*t
, TValue
*key
, StkId val
) {
202 int loop
; /* counter to avoid infinite loops */
203 for (loop
= 0; loop
< MAXTAGLOOP
; loop
++) {
205 if (ttistable(t
)) { /* 't' is a table? */
206 Table
*h
= hvalue(t
);
207 TValue
*oldval
= cast(TValue
*, luaH_get(h
, key
));
208 /* if previous value is not nil, there must be a previous entry
209 in the table; a metamethod has no relevance */
210 if (!ttisnil(oldval
) ||
211 /* previous value is nil; must check the metamethod */
212 ((tm
= fasttm(L
, h
->metatable
, TM_NEWINDEX
)) == NULL
&&
213 /* no metamethod; is there a previous entry in the table? */
214 (oldval
!= luaO_nilobject
||
215 /* no previous entry; must create one. (The next test is
216 always true; we only need the assignment.) */
217 (oldval
= luaH_newkey(L
, h
, key
), 1)))) {
218 /* no metamethod and (now) there is an entry with given key */
219 setobj2t(L
, oldval
, val
); /* assign new value to that entry */
220 invalidateTMcache(h
);
221 luaC_barrierback(L
, h
, val
);
224 /* else will try the metamethod */
226 else /* not a table; check metamethod */
227 if (ttisnil(tm
= luaT_gettmbyobj(L
, t
, TM_NEWINDEX
)))
228 luaG_typeerror(L
, t
, "index");
229 /* try the metamethod */
230 if (ttisfunction(tm
)) {
231 luaT_callTM(L
, tm
, t
, key
, val
, 0);
234 t
= tm
; /* else repeat assignment over 'tm' */
236 luaG_runerror(L
, "settable chain too long; possible loop");
241 ** Compare two strings 'ls' x 'rs', returning an integer smaller-equal-
242 ** -larger than zero if 'ls' is smaller-equal-larger than 'rs'.
243 ** The code is a little tricky because it allows '\0' in the strings
244 ** and it uses 'strcoll' (to respect locales) for each segments
247 static int l_strcmp (const TString
*ls
, const TString
*rs
) {
248 const char *l
= getstr(ls
);
249 size_t ll
= tsslen(ls
);
250 const char *r
= getstr(rs
);
251 size_t lr
= tsslen(rs
);
252 for (;;) { /* for each segment */
253 int temp
= strcoll(l
, r
);
254 if (temp
!= 0) /* not equal? */
255 return temp
; /* done */
256 else { /* strings are equal up to a '\0' */
257 size_t len
= strlen(l
); /* index of first '\0' in both strings */
258 if (len
== lr
) /* 'rs' is finished? */
259 return (len
== ll
) ? 0 : 1; /* check 'ls' */
260 else if (len
== ll
) /* 'ls' is finished? */
261 return -1; /* 'ls' is smaller than 'rs' ('rs' is not finished) */
262 /* both strings longer than 'len'; go on comparing after the '\0' */
264 l
+= len
; ll
-= len
; r
+= len
; lr
-= len
;
271 ** Check whether integer 'i' is less than float 'f'. If 'i' has an
272 ** exact representation as a float ('l_intfitsf'), compare numbers as
273 ** floats. Otherwise, if 'f' is outside the range for integers, result
274 ** is trivial. Otherwise, compare them as integers. (When 'i' has no
275 ** float representation, either 'f' is "far away" from 'i' or 'f' has
276 ** no precision left for a fractional part; either way, how 'f' is
277 ** truncated is irrelevant.) When 'f' is NaN, comparisons must result
280 static int LTintfloat (lua_Integer i
, lua_Number f
) {
281 #if defined(l_intfitsf)
282 if (!l_intfitsf(i
)) {
283 if (f
>= -cast_num(LUA_MININTEGER
)) /* -minint == maxint + 1 */
284 return 1; /* f >= maxint + 1 > i */
285 else if (f
> cast_num(LUA_MININTEGER
)) /* minint < f <= maxint ? */
286 return (i
< cast(lua_Integer
, f
)); /* compare them as integers */
287 else /* f <= minint <= i (or 'f' is NaN) --> not(i < f) */
291 return luai_numlt(cast_num(i
), f
); /* compare them as floats */
296 ** Check whether integer 'i' is less than or equal to float 'f'.
297 ** See comments on previous function.
299 static int LEintfloat (lua_Integer i
, lua_Number f
) {
300 #if defined(l_intfitsf)
301 if (!l_intfitsf(i
)) {
302 if (f
>= -cast_num(LUA_MININTEGER
)) /* -minint == maxint + 1 */
303 return 1; /* f >= maxint + 1 > i */
304 else if (f
>= cast_num(LUA_MININTEGER
)) /* minint <= f <= maxint ? */
305 return (i
<= cast(lua_Integer
, f
)); /* compare them as integers */
306 else /* f < minint <= i (or 'f' is NaN) --> not(i <= f) */
310 return luai_numle(cast_num(i
), f
); /* compare them as floats */
315 ** Return 'l < r', for numbers.
317 static int LTnum (const TValue
*l
, const TValue
*r
) {
318 if (ttisinteger(l
)) {
319 lua_Integer li
= ivalue(l
);
321 return li
< ivalue(r
); /* both are integers */
323 else /* 'l' is int and 'r' is float */
324 return LTintfloat(li
, fltvalue(r
)); /* l < r ? */
329 lua_Number lf
= fltvalue(l
); /* 'l' must be float */
331 return luai_numlt(lf
, fltvalue(r
)); /* both are float */
332 else if (luai_numisnan(lf
)) /* 'r' is int and 'l' is float */
333 return 0; /* NaN < i is always false */
334 else /* without NaN, (l < r) <--> not(r <= l) */
335 return !LEintfloat(ivalue(r
), lf
); /* not (r <= l) ? */
342 ** Return 'l <= r', for numbers.
344 static int LEnum (const TValue
*l
, const TValue
*r
) {
345 if (ttisinteger(l
)) {
346 lua_Integer li
= ivalue(l
);
348 return li
<= ivalue(r
); /* both are integers */
350 else /* 'l' is int and 'r' is float */
351 return LEintfloat(li
, fltvalue(r
)); /* l <= r ? */
356 lua_Number lf
= fltvalue(l
); /* 'l' must be float */
358 return luai_numle(lf
, fltvalue(r
)); /* both are float */
359 else if (luai_numisnan(lf
)) /* 'r' is int and 'l' is float */
360 return 0; /* NaN <= i is always false */
361 else /* without NaN, (l <= r) <--> not(r < l) */
362 return !LTintfloat(ivalue(r
), lf
); /* not (r < l) ? */
369 ** Main operation less than; return 'l < r'.
371 int luaV_lessthan (lua_State
*L
, const TValue
*l
, const TValue
*r
) {
373 if (ttisnumber(l
) && ttisnumber(r
)) /* both operands are numbers? */
375 else if (ttisstring(l
) && ttisstring(r
)) /* both are strings? */
376 return l_strcmp(tsvalue(l
), tsvalue(r
)) < 0;
377 else if ((res
= luaT_callorderTM(L
, l
, r
, TM_LT
)) < 0) /* no metamethod? */
378 luaG_ordererror(L
, l
, r
); /* error */
384 ** Main operation less than or equal to; return 'l <= r'. If it needs
385 ** a metamethod and there is no '__le', try '__lt', based on
386 ** l <= r iff !(r < l) (assuming a total order). If the metamethod
387 ** yields during this substitution, the continuation has to know
388 ** about it (to negate the result of r<l); bit CIST_LEQ in the call
389 ** status keeps that information.
391 int luaV_lessequal (lua_State
*L
, const TValue
*l
, const TValue
*r
) {
393 if (ttisnumber(l
) && ttisnumber(r
)) /* both operands are numbers? */
395 else if (ttisstring(l
) && ttisstring(r
)) /* both are strings? */
396 return l_strcmp(tsvalue(l
), tsvalue(r
)) <= 0;
397 else if ((res
= luaT_callorderTM(L
, l
, r
, TM_LE
)) >= 0) /* try 'le' */
399 else { /* try 'lt': */
400 L
->ci
->callstatus
|= CIST_LEQ
; /* mark it is doing 'lt' for 'le' */
401 res
= luaT_callorderTM(L
, r
, l
, TM_LT
);
402 L
->ci
->callstatus
^= CIST_LEQ
; /* clear mark */
404 luaG_ordererror(L
, l
, r
);
405 return !res
; /* result is negated */
411 ** Main operation for equality of Lua values; return 't1 == t2'.
412 ** L == NULL means raw equality (no metamethods)
414 int luaV_equalobj (lua_State
*L
, const TValue
*t1
, const TValue
*t2
) {
416 if (ttype(t1
) != ttype(t2
)) { /* not the same variant? */
418 if (ttnov(t1
) != ttnov(t2
) || ttnov(t1
) != LUA_TNUMBER
)
419 return 0; /* only numbers can be equal with different variants */
420 else { /* two numbers with different variants */
421 lua_Integer i1
, i2
; /* compare them as integers */
422 return (tointeger(t1
, &i1
) && tointeger(t2
, &i2
) && i1
== i2
);
425 return 0; /* numbers have only the integer variant */
428 /* values have same type and same variant */
430 case LUA_TNIL
: return 1;
431 case LUA_TNUMINT
: return (ivalue(t1
) == ivalue(t2
));
433 case LUA_TNUMFLT
: return luai_numeq(fltvalue(t1
), fltvalue(t2
));
435 case LUA_TBOOLEAN
: return bvalue(t1
) == bvalue(t2
); /* true must be 1 !! */
436 case LUA_TLIGHTUSERDATA
: return pvalue(t1
) == pvalue(t2
);
437 case LUA_TLCF
: return fvalue(t1
) == fvalue(t2
);
438 case LUA_TSHRSTR
: return eqshrstr(tsvalue(t1
), tsvalue(t2
));
439 case LUA_TLNGSTR
: return luaS_eqlngstr(tsvalue(t1
), tsvalue(t2
));
440 case LUA_TUSERDATA
: {
441 if (uvalue(t1
) == uvalue(t2
)) return 1;
442 else if (L
== NULL
) return 0;
443 tm
= fasttm(L
, uvalue(t1
)->metatable
, TM_EQ
);
445 tm
= fasttm(L
, uvalue(t2
)->metatable
, TM_EQ
);
446 break; /* will try TM */
449 if (hvalue(t1
) == hvalue(t2
)) return 1;
450 else if (L
== NULL
) return 0;
451 tm
= fasttm(L
, hvalue(t1
)->metatable
, TM_EQ
);
453 tm
= fasttm(L
, hvalue(t2
)->metatable
, TM_EQ
);
454 break; /* will try TM */
457 return gcvalue(t1
) == gcvalue(t2
);
459 if (tm
== NULL
) /* no TM? */
460 return 0; /* objects are different */
461 luaT_callTM(L
, tm
, t1
, t2
, L
->top
, 1); /* call TM */
462 return !l_isfalse(L
->top
);
466 /* macro used by 'luaV_concat' to ensure that element at 'o' is a string */
467 #define tostring(L,o) \
468 (ttisstring(o) || (cvt2str(o) && (luaO_tostring(L, o), 1)))
470 #define isemptystr(o) (ttisshrstring(o) && tsvalue(o)->shrlen == 0)
473 ** Main operation for concatenation: concat 'total' values in the stack,
474 ** from 'L->top - total' up to 'L->top - 1'.
476 void luaV_concat (lua_State
*L
, int total
) {
477 lua_assert(total
>= 2);
480 int n
= 2; /* number of elements handled in this pass (at least 2) */
481 if (!(ttisstring(top
-2) || cvt2str(top
-2)) || !tostring(L
, top
-1))
482 luaT_trybinTM(L
, top
-2, top
-1, top
-2, TM_CONCAT
);
483 else if (isemptystr(top
- 1)) /* second operand is empty? */
484 cast_void(tostring(L
, top
- 2)); /* result is first operand */
485 else if (isemptystr(top
- 2)) { /* first operand is an empty string? */
486 setobjs2s(L
, top
- 2, top
- 1); /* result is second op. */
489 /* at least two non-empty string values; get as many as possible */
490 size_t tl
= vslen(top
- 1);
493 /* collect total length */
494 for (i
= 1; i
< total
&& tostring(L
, top
-i
-1); i
++) {
495 size_t l
= vslen(top
- i
- 1);
496 if (l
>= (MAX_SIZE
/sizeof(char)) - tl
)
497 luaG_runerror(L
, "string length overflow");
500 buffer
= luaZ_openspace(L
, &G(L
)->buff
, tl
);
503 do { /* copy all strings to buffer */
504 size_t l
= vslen(top
- i
);
505 memcpy(buffer
+tl
, svalue(top
-i
), l
* sizeof(char));
508 setsvalue2s(L
, top
-n
, luaS_newlstr(L
, buffer
, tl
)); /* create result */
510 total
-= n
-1; /* got 'n' strings to create 1 new */
511 L
->top
-= n
-1; /* popped 'n' strings and pushed one */
512 } while (total
> 1); /* repeat until only 1 result left */
517 ** Main operation 'ra' = #rb'.
519 void luaV_objlen (lua_State
*L
, StkId ra
, const TValue
*rb
) {
523 Table
*h
= hvalue(rb
);
524 tm
= fasttm(L
, h
->metatable
, TM_LEN
);
525 if (tm
) break; /* metamethod? break switch to call it */
526 setivalue(ra
, luaH_getn(h
)); /* else primitive len */
530 setivalue(ra
, tsvalue(rb
)->shrlen
);
534 setivalue(ra
, tsvalue(rb
)->u
.lnglen
);
537 default: { /* try metamethod */
538 tm
= luaT_gettmbyobj(L
, rb
, TM_LEN
);
539 if (ttisnil(tm
)) /* no metamethod? */
540 luaG_typeerror(L
, rb
, "get length of");
544 luaT_callTM(L
, tm
, rb
, rb
, ra
, 1);
549 ** Integer division; return 'm // n', that is, floor(m/n).
550 ** C division truncates its result (rounds towards zero).
551 ** 'floor(q) == trunc(q)' when 'q >= 0' or when 'q' is integer,
552 ** otherwise 'floor(q) == trunc(q) - 1'.
554 lua_Integer
luaV_div (lua_State
*L
, lua_Integer m
, lua_Integer n
) {
555 if (l_castS2U(n
) + 1u <= 1u) { /* special cases: -1 or 0 */
557 luaG_runerror(L
, "attempt to divide by zero");
558 return intop(-, 0, m
); /* n==-1; avoid overflow with 0x80000...//-1 */
561 lua_Integer q
= m
/ n
; /* perform C division */
562 if ((m
^ n
) < 0 && m
% n
!= 0) /* 'm/n' would be negative non-integer? */
563 q
-= 1; /* correct result for different rounding */
570 ** Integer modulus; return 'm % n'. (Assume that C '%' with
571 ** negative operands follows C99 behavior. See previous comment
574 lua_Integer
luaV_mod (lua_State
*L
, lua_Integer m
, lua_Integer n
) {
575 if (l_castS2U(n
) + 1u <= 1u) { /* special cases: -1 or 0 */
577 luaG_runerror(L
, "attempt to perform 'n%%0'");
578 return 0; /* m % -1 == 0; avoid overflow with 0x80000...%-1 */
581 lua_Integer r
= m
% n
;
582 if (r
!= 0 && (m
^ n
) < 0) /* 'm/n' would be non-integer negative? */
583 r
+= n
; /* correct result for different rounding */
589 /* number of bits in an integer */
590 #define NBITS cast_int(sizeof(lua_Integer) * CHAR_BIT)
593 ** Shift left operation. (Shift right just negates 'y'.)
595 lua_Integer
luaV_shiftl (lua_Integer x
, lua_Integer y
) {
596 if (y
< 0) { /* shift right? */
597 if (y
<= -NBITS
) return 0;
598 else return intop(>>, x
, -y
);
600 else { /* shift left */
601 if (y
>= NBITS
) return 0;
602 else return intop(<<, x
, y
);
608 ** check whether cached closure in prototype 'p' may be reused, that is,
609 ** whether there is a cached closure with the same upvalues needed by
610 ** new closure to be created.
612 static LClosure
*getcached (Proto
*p
, UpVal
**encup
, StkId base
) {
613 LClosure
*c
= p
->cache
;
614 if (c
!= NULL
) { /* is there a cached closure? */
615 int nup
= p
->sizeupvalues
;
616 Upvaldesc
*uv
= p
->upvalues
;
618 for (i
= 0; i
< nup
; i
++) { /* check whether it has right upvalues */
619 TValue
*v
= uv
[i
].instack
? base
+ uv
[i
].idx
: encup
[uv
[i
].idx
]->v
;
620 if (c
->upvals
[i
]->v
!= v
)
621 return NULL
; /* wrong upvalue; cannot reuse closure */
624 return c
; /* return cached closure (or NULL if no cached closure) */
629 ** create a new Lua closure, push it in the stack, and initialize
630 ** its upvalues. Note that the closure is not cached if prototype is
631 ** already black (which means that 'cache' was already cleared by the
634 static void pushclosure (lua_State
*L
, Proto
*p
, UpVal
**encup
, StkId base
,
636 int nup
= p
->sizeupvalues
;
637 Upvaldesc
*uv
= p
->upvalues
;
639 LClosure
*ncl
= luaF_newLclosure(L
, nup
);
641 setclLvalue(L
, ra
, ncl
); /* anchor new closure in stack */
642 for (i
= 0; i
< nup
; i
++) { /* fill in its upvalues */
643 if (uv
[i
].instack
) /* upvalue refers to local variable? */
644 ncl
->upvals
[i
] = luaF_findupval(L
, base
+ uv
[i
].idx
);
645 else /* get upvalue from enclosing function */
646 ncl
->upvals
[i
] = encup
[uv
[i
].idx
];
647 ncl
->upvals
[i
]->refcount
++;
648 /* new closure is white, so we do not need a barrier here */
650 if (!isblack(p
)) /* cache will not break GC invariant? */
651 p
->cache
= ncl
; /* save it on cache for reuse */
656 ** finish execution of an opcode interrupted by an yield
658 void luaV_finishOp (lua_State
*L
) {
659 CallInfo
*ci
= L
->ci
;
660 StkId base
= ci
->u
.l
.base
;
661 Instruction inst
= *(ci
->u
.l
.savedpc
- 1); /* interrupted instruction */
662 OpCode op
= GET_OPCODE(inst
);
663 switch (op
) { /* finish its execution */
665 case OP_ADD
: case OP_SUB
: case OP_MUL
: case OP_DIV
: case OP_IDIV
:
667 case OP_ADD
: case OP_SUB
: case OP_MUL
: case OP_IDIV
:
669 case OP_BAND
: case OP_BOR
: case OP_BXOR
: case OP_SHL
: case OP_SHR
:
671 case OP_MOD
: case OP_POW
:
675 case OP_UNM
: case OP_BNOT
: case OP_LEN
:
676 case OP_GETTABUP
: case OP_GETTABLE
: case OP_SELF
: {
677 setobjs2s(L
, base
+ GETARG_A(inst
), --L
->top
);
680 case OP_LE
: case OP_LT
: case OP_EQ
: {
681 int res
= !l_isfalse(L
->top
- 1);
683 if (ci
->callstatus
& CIST_LEQ
) { /* "<=" using "<" instead? */
684 lua_assert(op
== OP_LE
);
685 ci
->callstatus
^= CIST_LEQ
; /* clear mark */
686 res
= !res
; /* negate result */
688 lua_assert(GET_OPCODE(*ci
->u
.l
.savedpc
) == OP_JMP
);
689 if (res
!= GETARG_A(inst
)) /* condition failed? */
690 ci
->u
.l
.savedpc
++; /* skip jump instruction */
694 StkId top
= L
->top
- 1; /* top when 'luaT_trybinTM' was called */
695 int b
= GETARG_B(inst
); /* first element to concatenate */
696 int total
= cast_int(top
- 1 - (base
+ b
)); /* yet to concatenate */
697 setobj2s(L
, top
- 2, top
); /* put TM result in proper position */
698 if (total
> 1) { /* are there elements to concat? */
699 L
->top
= top
- 1; /* top is one after last element (at top-2) */
700 luaV_concat(L
, total
); /* concat them (may yield again) */
702 /* move final result to final position */
703 setobj2s(L
, ci
->u
.l
.base
+ GETARG_A(inst
), L
->top
- 1);
704 L
->top
= ci
->top
; /* restore top */
708 lua_assert(GET_OPCODE(*ci
->u
.l
.savedpc
) == OP_TFORLOOP
);
709 L
->top
= ci
->top
; /* correct top */
713 if (GETARG_C(inst
) - 1 >= 0) /* nresults >= 0? */
714 L
->top
= ci
->top
; /* adjust results */
717 case OP_TAILCALL
: case OP_SETTABUP
: case OP_SETTABLE
:
719 default: lua_assert(0);
727 ** {==================================================================
728 ** Function 'luaV_execute': main interpreter loop
729 ** ===================================================================
734 ** some macros for common tasks in 'luaV_execute'
737 #if !defined(luai_runtimecheck)
738 #define luai_runtimecheck(L, c) /* void */
742 #define RA(i) (base+GETARG_A(i))
743 /* to be used after possible stack reallocation */
744 #define RB(i) check_exp(getBMode(GET_OPCODE(i)) == OpArgR, base+GETARG_B(i))
745 #define RC(i) check_exp(getCMode(GET_OPCODE(i)) == OpArgR, base+GETARG_C(i))
746 #define RKB(i) check_exp(getBMode(GET_OPCODE(i)) == OpArgK, \
747 ISK(GETARG_B(i)) ? k+INDEXK(GETARG_B(i)) : base+GETARG_B(i))
748 #define RKC(i) check_exp(getCMode(GET_OPCODE(i)) == OpArgK, \
749 ISK(GETARG_C(i)) ? k+INDEXK(GETARG_C(i)) : base+GETARG_C(i))
751 (k + (GETARG_Bx(i) != 0 ? GETARG_Bx(i) - 1 : GETARG_Ax(*ci->u.l.savedpc++)))
754 /* execute a jump instruction */
755 #define dojump(ci,i,e) \
756 { int a = GETARG_A(i); \
757 if (a > 0) luaF_close(L, ci->u.l.base + a - 1); \
758 ci->u.l.savedpc += GETARG_sBx(i) + e; }
760 /* for test instructions, execute the jump instruction that follows it */
761 #define donextjump(ci) { i = *ci->u.l.savedpc; dojump(ci, i, 1); }
764 #define Protect(x) { {x;}; base = ci->u.l.base; }
766 #define checkGC(L,c) \
767 Protect( luaC_condGC(L,{L->top = (c); /* limit of live values */ \
769 L->top = ci->top;}) /* restore top */ \
770 luai_threadyield(L); )
773 #define vmdispatch(o) switch(o)
774 #define vmcase(l) case l:
775 #define vmbreak break
777 void luaV_execute (lua_State
*L
) {
778 CallInfo
*ci
= L
->ci
;
782 newframe
: /* reentry point when frame changes (call/return) */
783 lua_assert(ci
== L
->ci
);
784 cl
= clLvalue(ci
->func
);
787 /* main loop of interpreter */
789 Instruction i
= *(ci
->u
.l
.savedpc
++);
791 if ((L
->hookmask
& (LUA_MASKLINE
| LUA_MASKCOUNT
)) &&
792 (--L
->hookcount
== 0 || L
->hookmask
& LUA_MASKLINE
)) {
793 Protect(luaG_traceexec(L
));
795 /* WARNING: several calls may realloc the stack and invalidate 'ra' */
797 lua_assert(base
== ci
->u
.l
.base
);
798 lua_assert(base
<= L
->top
&& L
->top
< L
->stack
+ L
->stacksize
);
799 vmdispatch (GET_OPCODE(i
)) {
801 setobjs2s(L
, ra
, RB(i
));
805 TValue
*rb
= k
+ GETARG_Bx(i
);
811 lua_assert(GET_OPCODE(*ci
->u
.l
.savedpc
) == OP_EXTRAARG
);
812 rb
= k
+ GETARG_Ax(*ci
->u
.l
.savedpc
++);
816 vmcase(OP_LOADBOOL
) {
817 setbvalue(ra
, GETARG_B(i
));
818 if (GETARG_C(i
)) ci
->u
.l
.savedpc
++; /* skip next instruction (if C) */
828 vmcase(OP_GETUPVAL
) {
830 setobj2s(L
, ra
, cl
->upvals
[b
]->v
);
833 vmcase(OP_GETTABUP
) {
835 Protect(luaV_gettable(L
, cl
->upvals
[b
]->v
, RKC(i
), ra
));
838 vmcase(OP_GETTABLE
) {
839 Protect(luaV_gettable(L
, RB(i
), RKC(i
), ra
));
842 vmcase(OP_SETTABUP
) {
844 Protect(luaV_settable(L
, cl
->upvals
[a
]->v
, RKB(i
), RKC(i
)));
847 vmcase(OP_SETUPVAL
) {
848 UpVal
*uv
= cl
->upvals
[GETARG_B(i
)];
849 setobj(L
, uv
->v
, ra
);
850 luaC_upvalbarrier(L
, uv
);
853 vmcase(OP_SETTABLE
) {
854 Protect(luaV_settable(L
, ra
, RKB(i
), RKC(i
)));
857 vmcase(OP_NEWTABLE
) {
860 Table
*t
= luaH_new(L
);
862 if (b
!= 0 || c
!= 0)
863 luaH_resize(L
, t
, luaO_fb2int(b
), luaO_fb2int(c
));
869 setobjs2s(L
, ra
+1, rb
);
870 Protect(luaV_gettable(L
, rb
, RKC(i
), ra
));
877 lua_Number nb
; lua_Number nc
;
878 if (ttisinteger(rb
) && ttisinteger(rc
)) {
879 lua_Integer ib
= ivalue(rb
); lua_Integer ic
= ivalue(rc
);
880 setivalue(ra
, intop(+, ib
, ic
));
882 else if (tonumber(rb
, &nb
) && tonumber(rc
, &nc
)) {
883 setfltvalue(ra
, luai_numadd(L
, nb
, nc
));
886 lua_Integer ib
; lua_Integer ic
;
887 if (tointeger(rb
, &ib
) && tointeger(rc
, &ic
)) {
888 setivalue(ra
, intop(+, ib
, ic
));
891 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_ADD
)); }
898 lua_Number nb
; lua_Number nc
;
899 if (ttisinteger(rb
) && ttisinteger(rc
)) {
900 lua_Integer ib
= ivalue(rb
); lua_Integer ic
= ivalue(rc
);
901 setivalue(ra
, intop(-, ib
, ic
));
903 else if (tonumber(rb
, &nb
) && tonumber(rc
, &nc
)) {
904 setfltvalue(ra
, luai_numsub(L
, nb
, nc
));
907 lua_Integer ib
; lua_Integer ic
;
908 if (tointeger(rb
, &ib
) && tointeger(rc
, &ic
)) {
909 setivalue(ra
, intop(-, ib
, ic
));
912 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_SUB
)); }
919 lua_Number nb
; lua_Number nc
;
920 if (ttisinteger(rb
) && ttisinteger(rc
)) {
921 lua_Integer ib
= ivalue(rb
); lua_Integer ic
= ivalue(rc
);
922 setivalue(ra
, intop(*, ib
, ic
));
924 else if (tonumber(rb
, &nb
) && tonumber(rc
, &nc
)) {
925 setfltvalue(ra
, luai_nummul(L
, nb
, nc
));
928 lua_Integer ib
; lua_Integer ic
;
929 if (tointeger(rb
, &ib
) && tointeger(rc
, &ic
)) {
930 setivalue(ra
, intop(*, ib
, ic
));
933 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_MUL
)); }
937 vmcase(OP_DIV
) { /* float division (always with floats) */
940 lua_Number nb
; lua_Number nc
;
941 if (tonumber(rb
, &nb
) && tonumber(rc
, &nc
)) {
942 setfltvalue(ra
, luai_numdiv(L
, nb
, nc
));
944 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_DIV
)); }
951 lua_Integer ib
; lua_Integer ic
;
952 if (tointeger(rb
, &ib
) && tointeger(rc
, &ic
)) {
953 setivalue(ra
, intop(&, ib
, ic
));
955 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_BAND
)); }
961 lua_Integer ib
; lua_Integer ic
;
962 if (tointeger(rb
, &ib
) && tointeger(rc
, &ic
)) {
963 setivalue(ra
, intop(|, ib
, ic
));
965 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_BOR
)); }
971 lua_Integer ib
; lua_Integer ic
;
972 if (tointeger(rb
, &ib
) && tointeger(rc
, &ic
)) {
973 setivalue(ra
, intop(^, ib
, ic
));
975 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_BXOR
)); }
981 lua_Integer ib
; lua_Integer ic
;
982 if (tointeger(rb
, &ib
) && tointeger(rc
, &ic
)) {
983 setivalue(ra
, luaV_shiftl(ib
, ic
));
985 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_SHL
)); }
991 lua_Integer ib
; lua_Integer ic
;
992 if (tointeger(rb
, &ib
) && tointeger(rc
, &ic
)) {
993 setivalue(ra
, luaV_shiftl(ib
, -ic
));
995 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_SHR
)); }
1000 TValue
*rc
= RKC(i
);
1002 lua_Number nb
; lua_Number nc
;
1003 if (ttisinteger(rb
) && ttisinteger(rc
)) {
1004 lua_Integer ib
= ivalue(rb
); lua_Integer ic
= ivalue(rc
);
1005 setivalue(ra
, luaV_mod(L
, ib
, ic
));
1007 else if (tonumber(rb
, &nb
) && tonumber(rc
, &nc
)) {
1009 luai_nummod(L
, nb
, nc
, m
);
1013 lua_Integer ib
; lua_Integer ic
;
1014 if (tointeger(rb
, &ib
) && tointeger(rc
, &ic
)) {
1015 setivalue(ra
, luaV_mod(L
, ib
, ic
));
1018 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_MOD
)); }
1021 vmcase(OP_IDIV
) { /* floor division */
1022 TValue
*rb
= RKB(i
);
1023 TValue
*rc
= RKC(i
);
1025 lua_Number nb
; lua_Number nc
;
1026 if (ttisinteger(rb
) && ttisinteger(rc
)) {
1027 lua_Integer ib
= ivalue(rb
); lua_Integer ic
= ivalue(rc
);
1028 setivalue(ra
, luaV_div(L
, ib
, ic
));
1030 else if (tonumber(rb
, &nb
) && tonumber(rc
, &nc
)) {
1031 setfltvalue(ra
, luai_numidiv(L
, nb
, nc
));
1034 lua_Integer ib
; lua_Integer ic
;
1035 if (tointeger(rb
, &ib
) && tointeger(rc
, &ic
)) {
1036 setivalue(ra
, luaV_div(L
, ib
, ic
));
1039 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_IDIV
)); }
1044 TValue
*rb
= RKB(i
);
1045 TValue
*rc
= RKC(i
);
1046 lua_Number nb
; lua_Number nc
;
1047 if (tonumber(rb
, &nb
) && tonumber(rc
, &nc
)) {
1048 setfltvalue(ra
, luai_numpow(L
, nb
, nc
));
1050 else { Protect(luaT_trybinTM(L
, rb
, rc
, ra
, TM_POW
)); }
1058 if (ttisinteger(rb
)) {
1059 lua_Integer ib
= ivalue(rb
);
1060 setivalue(ra
, intop(-, 0, ib
));
1062 else if (tonumber(rb
, &nb
)) {
1063 setfltvalue(ra
, luai_numunm(L
, nb
));
1067 if (tointeger(rb
, &ib
)) {
1068 setivalue(ra
, intop(-, 0, ib
));
1072 Protect(luaT_trybinTM(L
, rb
, rb
, ra
, TM_UNM
));
1079 if (tointeger(rb
, &ib
)) {
1080 setivalue(ra
, intop(^, ~l_castS2U(0), ib
));
1083 Protect(luaT_trybinTM(L
, rb
, rb
, ra
, TM_BNOT
));
1089 int res
= l_isfalse(rb
); /* next assignment may change this value */
1094 Protect(luaV_objlen(L
, ra
, RB(i
)));
1098 int b
= GETARG_B(i
);
1099 int c
= GETARG_C(i
);
1101 L
->top
= base
+ c
+ 1; /* mark the end of concat operands */
1102 Protect(luaV_concat(L
, c
- b
+ 1));
1103 ra
= RA(i
); /* 'luav_concat' may invoke TMs and move the stack */
1105 setobjs2s(L
, ra
, rb
);
1106 checkGC(L
, (ra
>= rb
? ra
+ 1 : rb
));
1107 L
->top
= ci
->top
; /* restore top */
1115 TValue
*rb
= RKB(i
);
1116 TValue
*rc
= RKC(i
);
1118 if (cast_int(luaV_equalobj(L
, rb
, rc
)) != GETARG_A(i
))
1127 if (luaV_lessthan(L
, RKB(i
), RKC(i
)) != GETARG_A(i
))
1136 if (luaV_lessequal(L
, RKB(i
), RKC(i
)) != GETARG_A(i
))
1144 if (GETARG_C(i
) ? l_isfalse(ra
) : !l_isfalse(ra
))
1150 vmcase(OP_TESTSET
) {
1152 if (GETARG_C(i
) ? l_isfalse(rb
) : !l_isfalse(rb
))
1155 setobjs2s(L
, ra
, rb
);
1161 int b
= GETARG_B(i
);
1162 int nresults
= GETARG_C(i
) - 1;
1163 if (b
!= 0) L
->top
= ra
+b
; /* else previous instruction set top */
1164 if (luaD_precall(L
, ra
, nresults
)) { /* C function? */
1165 if (nresults
>= 0) L
->top
= ci
->top
; /* adjust results */
1166 base
= ci
->u
.l
.base
;
1168 else { /* Lua function */
1170 ci
->callstatus
|= CIST_REENTRY
;
1171 goto newframe
; /* restart luaV_execute over new Lua function */
1175 vmcase(OP_TAILCALL
) {
1176 int b
= GETARG_B(i
);
1177 if (b
!= 0) L
->top
= ra
+b
; /* else previous instruction set top */
1178 lua_assert(GETARG_C(i
) - 1 == LUA_MULTRET
);
1179 if (luaD_precall(L
, ra
, LUA_MULTRET
)) /* C function? */
1180 base
= ci
->u
.l
.base
;
1182 /* tail call: put called frame (n) in place of caller one (o) */
1183 CallInfo
*nci
= L
->ci
; /* called frame */
1184 CallInfo
*oci
= nci
->previous
; /* caller frame */
1185 StkId nfunc
= nci
->func
; /* called function */
1186 StkId ofunc
= oci
->func
; /* caller function */
1187 /* last stack slot filled by 'precall' */
1188 StkId lim
= nci
->u
.l
.base
+ getproto(nfunc
)->numparams
;
1190 /* close all upvalues from previous call */
1191 if (cl
->p
->sizep
> 0) luaF_close(L
, oci
->u
.l
.base
);
1192 /* move new frame into old one */
1193 for (aux
= 0; nfunc
+ aux
< lim
; aux
++)
1194 setobjs2s(L
, ofunc
+ aux
, nfunc
+ aux
);
1195 oci
->u
.l
.base
= ofunc
+ (nci
->u
.l
.base
- nfunc
); /* correct base */
1196 oci
->top
= L
->top
= ofunc
+ (L
->top
- nfunc
); /* correct top */
1197 oci
->u
.l
.savedpc
= nci
->u
.l
.savedpc
;
1198 oci
->callstatus
|= CIST_TAIL
; /* function was tail called */
1199 ci
= L
->ci
= oci
; /* remove new frame */
1200 lua_assert(L
->top
== oci
->u
.l
.base
+ getproto(ofunc
)->maxstacksize
);
1201 goto newframe
; /* restart luaV_execute over new Lua function */
1206 int b
= GETARG_B(i
);
1207 if (cl
->p
->sizep
> 0) luaF_close(L
, base
);
1208 b
= luaD_poscall(L
, ra
, (b
!= 0 ? b
- 1 : L
->top
- ra
));
1209 if (!(ci
->callstatus
& CIST_REENTRY
)) /* 'ci' still the called one */
1210 return; /* external invocation: return */
1211 else { /* invocation via reentry: continue execution */
1213 if (b
) L
->top
= ci
->top
;
1214 lua_assert(isLua(ci
));
1215 lua_assert(GET_OPCODE(*((ci
)->u
.l
.savedpc
- 1)) == OP_CALL
);
1216 goto newframe
; /* restart luaV_execute over new Lua function */
1219 vmcase(OP_FORLOOP
) {
1221 if (ttisinteger(ra
)) { /* integer loop? */
1223 lua_Integer step
= ivalue(ra
+ 2);
1224 lua_Integer idx
= ivalue(ra
) + step
; /* increment index */
1225 lua_Integer limit
= ivalue(ra
+ 1);
1226 if ((0 < step
) ? (idx
<= limit
) : (limit
<= idx
)) {
1227 ci
->u
.l
.savedpc
+= GETARG_sBx(i
); /* jump back */
1228 chgivalue(ra
, idx
); /* update internal index... */
1229 setivalue(ra
+ 3, idx
); /* ...and external index */
1233 else { /* floating loop */
1234 lua_Number step
= fltvalue(ra
+ 2);
1235 lua_Number idx
= luai_numadd(L
, fltvalue(ra
), step
); /* inc. index */
1236 lua_Number limit
= fltvalue(ra
+ 1);
1237 if (luai_numlt(0, step
) ? luai_numle(idx
, limit
)
1238 : luai_numle(limit
, idx
)) {
1239 ci
->u
.l
.savedpc
+= GETARG_sBx(i
); /* jump back */
1240 chgfltvalue(ra
, idx
); /* update internal index... */
1241 setfltvalue(ra
+ 3, idx
); /* ...and external index */
1247 vmcase(OP_FORPREP
) {
1249 TValue
*plimit
= ra
+ 1;
1250 TValue
*pstep
= ra
+ 2;
1254 if (ttisinteger(init
) && ttisinteger(pstep
) &&
1255 forlimit(plimit
, &ilimit
, ivalue(pstep
), &stopnow
)) {
1256 /* all values are integer */
1257 lua_Integer initv
= (stopnow
? 0 : ivalue(init
));
1258 setivalue(plimit
, ilimit
);
1259 setivalue(init
, initv
- ivalue(pstep
));
1261 else { /* try making all values floats */
1262 lua_Number ninit
; lua_Number nlimit
; lua_Number nstep
;
1263 if (!tonumber(plimit
, &nlimit
))
1264 luaG_runerror(L
, "'for' limit must be a number");
1265 setfltvalue(plimit
, nlimit
);
1266 if (!tonumber(pstep
, &nstep
))
1267 luaG_runerror(L
, "'for' step must be a number");
1268 setfltvalue(pstep
, nstep
);
1269 if (!tonumber(init
, &ninit
))
1270 luaG_runerror(L
, "'for' initial value must be a number");
1271 setfltvalue(init
, luai_numsub(L
, ninit
, nstep
));
1274 lua_Integer initv
; lua_Integer step
;
1275 if (!tointeger(plimit
, &ilimit
))
1276 luaG_runerror(L
, "'for' limit must be a number");
1277 setivalue(plimit
, ilimit
);
1278 if (!tointeger(pstep
, &step
))
1279 luaG_runerror(L
, "'for' step must be a number");
1280 setivalue(pstep
, step
);
1281 if (!tointeger(init
, &initv
))
1282 luaG_runerror(L
, "'for' initial value must be a number");
1283 setivalue(init
, initv
- step
);
1285 ci
->u
.l
.savedpc
+= GETARG_sBx(i
);
1288 vmcase(OP_TFORCALL
) {
1289 StkId cb
= ra
+ 3; /* call base */
1290 setobjs2s(L
, cb
+2, ra
+2);
1291 setobjs2s(L
, cb
+1, ra
+1);
1292 setobjs2s(L
, cb
, ra
);
1293 L
->top
= cb
+ 3; /* func. + 2 args (state and index) */
1294 Protect(luaD_call(L
, cb
, GETARG_C(i
), 1));
1296 i
= *(ci
->u
.l
.savedpc
++); /* go to next instruction */
1298 lua_assert(GET_OPCODE(i
) == OP_TFORLOOP
);
1301 vmcase(OP_TFORLOOP
) {
1303 if (!ttisnil(ra
+ 1)) { /* continue loop? */
1304 setobjs2s(L
, ra
, ra
+ 1); /* save control variable */
1305 ci
->u
.l
.savedpc
+= GETARG_sBx(i
); /* jump back */
1309 vmcase(OP_SETLIST
) {
1310 int n
= GETARG_B(i
);
1311 int c
= GETARG_C(i
);
1314 if (n
== 0) n
= cast_int(L
->top
- ra
) - 1;
1316 lua_assert(GET_OPCODE(*ci
->u
.l
.savedpc
) == OP_EXTRAARG
);
1317 c
= GETARG_Ax(*ci
->u
.l
.savedpc
++);
1319 luai_runtimecheck(L
, ttistable(ra
));
1321 last
= ((c
-1)*LFIELDS_PER_FLUSH
) + n
;
1322 if (last
> h
->sizearray
) /* needs more space? */
1323 luaH_resizearray(L
, h
, last
); /* pre-allocate it at once */
1324 for (; n
> 0; n
--) {
1326 luaH_setint(L
, h
, last
--, val
);
1327 luaC_barrierback(L
, h
, val
);
1329 L
->top
= ci
->top
; /* correct top (in case of previous open call) */
1332 vmcase(OP_CLOSURE
) {
1333 Proto
*p
= cl
->p
->p
[GETARG_Bx(i
)];
1334 LClosure
*ncl
= getcached(p
, cl
->upvals
, base
); /* cached closure */
1335 if (ncl
== NULL
) /* no match? */
1336 pushclosure(L
, p
, cl
->upvals
, base
, ra
); /* create a new one */
1338 setclLvalue(L
, ra
, ncl
); /* push cashed closure */
1343 int b
= GETARG_B(i
) - 1;
1345 int n
= cast_int(base
- ci
->func
) - cl
->p
->numparams
- 1;
1346 if (b
< 0) { /* B == 0? */
1347 b
= n
; /* get all var. arguments */
1348 Protect(luaD_checkstack(L
, n
));
1349 ra
= RA(i
); /* previous call may change the stack */
1352 for (j
= 0; j
< b
; j
++) {
1354 setobjs2s(L
, ra
+ j
, base
- n
+ j
);
1357 setnilvalue(ra
+ j
);
1362 vmcase(OP_EXTRAARG
) {
1370 /* }================================================================== */