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- /*
- ** $Id: lvm.c,v 2.268 2016/02/05 19:59:14 roberto Exp $
- ** Lua virtual machine
- ** See Copyright Notice in lua.h
- */
- #define lvm_c
- #define LUA_CORE
- #include "lprefix.h"
- #include <float.h>
- #include <limits.h>
- #include <math.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include "lua.h"
- #include "ldebug.h"
- #include "ldo.h"
- #include "lfunc.h"
- #include "lgc.h"
- #include "lobject.h"
- #include "lopcodes.h"
- #include "lstate.h"
- #include "lstring.h"
- #include "ltable.h"
- #include "ltm.h"
- #include "lvm.h"
- /* limit for table tag-method chains (to avoid loops) */
- #define MAXTAGLOOP 2000
- /*
- ** 'l_intfitsf' checks whether a given integer can be converted to a
- ** float without rounding. Used in comparisons. Left undefined if
- ** all integers fit in a float precisely.
- */
- #if !defined(l_intfitsf)
- /* number of bits in the mantissa of a float */
- #define NBM (l_mathlim(MANT_DIG))
- /*
- ** Check whether some integers may not fit in a float, that is, whether
- ** (maxinteger >> NBM) > 0 (that implies (1 << NBM) <= maxinteger).
- ** (The shifts are done in parts to avoid shifting by more than the size
- ** of an integer. In a worst case, NBM == 113 for long double and
- ** sizeof(integer) == 32.)
- */
- #if ((((LUA_MAXINTEGER >> (NBM / 4)) >> (NBM / 4)) >> (NBM / 4)) \
- >> (NBM - (3 * (NBM / 4)))) > 0
- #define l_intfitsf(i) \
- (-((lua_Integer)1 << NBM) <= (i) && (i) <= ((lua_Integer)1 << NBM))
- #endif
- #endif
- /*
- ** Try to convert a value to a float. The float case is already handled
- ** by the macro 'tonumber'.
- */
- int luaV_tonumber_ (const TValue *obj, lua_Number *n) {
- TValue v;
- if (ttisinteger(obj)) {
- *n = cast_num(ivalue(obj));
- return 1;
- }
- else if (cvt2num(obj) && /* string convertible to number? */
- luaO_str2num(svalue(obj), &v) == vslen(obj) + 1) {
- *n = nvalue(&v); /* convert result of 'luaO_str2num' to a float */
- return 1;
- }
- else
- return 0; /* conversion failed */
- }
- /*
- ** try to convert a value to an integer, rounding according to 'mode':
- ** mode == 0: accepts only integral values
- ** mode == 1: takes the floor of the number
- ** mode == 2: takes the ceil of the number
- */
- int luaV_tointeger (const TValue *obj, lua_Integer *p, int mode) {
- TValue v;
- again:
- if (ttisfloat(obj)) {
- lua_Number n = fltvalue(obj);
- lua_Number f = l_floor(n);
- if (n != f) { /* not an integral value? */
- if (mode == 0) return 0; /* fails if mode demands integral value */
- else if (mode > 1) /* needs ceil? */
- f += 1; /* convert floor to ceil (remember: n != f) */
- }
- return lua_numbertointeger(f, p);
- }
- else if (ttisinteger(obj)) {
- *p = ivalue(obj);
- return 1;
- }
- else if (cvt2num(obj) &&
- luaO_str2num(svalue(obj), &v) == vslen(obj) + 1) {
- obj = &v;
- goto again; /* convert result from 'luaO_str2num' to an integer */
- }
- return 0; /* conversion failed */
- }
- /*
- ** Try to convert a 'for' limit to an integer, preserving the
- ** semantics of the loop.
- ** (The following explanation assumes a non-negative step; it is valid
- ** for negative steps mutatis mutandis.)
- ** If the limit can be converted to an integer, rounding down, that is
- ** it.
- ** Otherwise, check whether the limit can be converted to a number. If
- ** the number is too large, it is OK to set the limit as LUA_MAXINTEGER,
- ** which means no limit. If the number is too negative, the loop
- ** should not run, because any initial integer value is larger than the
- ** limit. So, it sets the limit to LUA_MININTEGER. 'stopnow' corrects
- ** the extreme case when the initial value is LUA_MININTEGER, in which
- ** case the LUA_MININTEGER limit would still run the loop once.
- */
- static int forlimit (const TValue *obj, lua_Integer *p, lua_Integer step,
- int *stopnow) {
- *stopnow = 0; /* usually, let loops run */
- if (!luaV_tointeger(obj, p, (step < 0 ? 2 : 1))) { /* not fit in integer? */
- lua_Number n; /* try to convert to float */
- if (!tonumber(obj, &n)) /* cannot convert to float? */
- return 0; /* not a number */
- if (luai_numlt(0, n)) { /* if true, float is larger than max integer */
- *p = LUA_MAXINTEGER;
- if (step < 0) *stopnow = 1;
- }
- else { /* float is smaller than min integer */
- *p = LUA_MININTEGER;
- if (step >= 0) *stopnow = 1;
- }
- }
- return 1;
- }
- /*
- ** Finish the table access 'val = t[key]'.
- ** if 'slot' is NULL, 't' is not a table; otherwise, 'slot' points to
- ** t[k] entry (which must be nil).
- */
- void luaV_finishget (lua_State *L, const TValue *t, TValue *key, StkId val,
- const TValue *slot) {
- int loop; /* counter to avoid infinite loops */
- const TValue *tm; /* metamethod */
- for (loop = 0; loop < MAXTAGLOOP; loop++) {
- if (slot == NULL) { /* 't' is not a table? */
- lua_assert(!ttistable(t));
- tm = luaT_gettmbyobj(L, t, TM_INDEX);
- if (ttisnil(tm))
- luaG_typeerror(L, t, "index"); /* no metamethod */
- /* else will try the metamethod */
- }
- else { /* 't' is a table */
- lua_assert(ttisnil(slot));
- tm = fasttm(L, hvalue(t)->metatable, TM_INDEX); /* table's metamethod */
- if (tm == NULL) { /* no metamethod? */
- setnilvalue(val); /* result is nil */
- return;
- }
- /* else will try the metamethod */
- }
- if (ttisfunction(tm)) { /* is metamethod a function? */
- luaT_callTM(L, tm, t, key, val, 1); /* call it */
- return;
- }
- t = tm; /* else try to access 'tm[key]' */
- if (luaV_fastget(L,t,key,slot,luaH_get)) { /* fast track? */
- setobj2s(L, val, slot); /* done */
- return;
- }
- /* else repeat (tail call 'luaV_finishget') */
- }
- luaG_runerror(L, "'__index' chain too long; possible loop");
- }
- /*
- ** Finish a table assignment 't[key] = val'.
- ** If 'slot' is NULL, 't' is not a table. Otherwise, 'slot' points
- ** to the entry 't[key]', or to 'luaO_nilobject' if there is no such
- ** entry. (The value at 'slot' must be nil, otherwise 'luaV_fastset'
- ** would have done the job.)
- */
- void luaV_finishset (lua_State *L, const TValue *t, TValue *key,
- StkId val, const TValue *slot) {
- int loop; /* counter to avoid infinite loops */
- for (loop = 0; loop < MAXTAGLOOP; loop++) {
- const TValue *tm; /* '__newindex' metamethod */
- if (slot != NULL) { /* is 't' a table? */
- Table *h = hvalue(t); /* save 't' table */
- lua_assert(ttisnil(slot)); /* old value must be nil */
- tm = fasttm(L, h->metatable, TM_NEWINDEX); /* get metamethod */
- if (tm == NULL) { /* no metamethod? */
- if (slot == luaO_nilobject) /* no previous entry? */
- slot = luaH_newkey(L, h, key); /* create one */
- /* no metamethod and (now) there is an entry with given key */
- setobj2t(L, cast(TValue *, slot), val); /* set its new value */
- invalidateTMcache(h);
- luaC_barrierback(L, h, val);
- return;
- }
- /* else will try the metamethod */
- }
- else { /* not a table; check metamethod */
- if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
- luaG_typeerror(L, t, "index");
- }
- /* try the metamethod */
- if (ttisfunction(tm)) {
- luaT_callTM(L, tm, t, key, val, 0);
- return;
- }
- t = tm; /* else repeat assignment over 'tm' */
- if (luaV_fastset(L, t, key, slot, luaH_get, val))
- return; /* done */
- /* else loop */
- }
- luaG_runerror(L, "'__newindex' chain too long; possible loop");
- }
- /*
- ** Compare two strings 'ls' x 'rs', returning an integer smaller-equal-
- ** -larger than zero if 'ls' is smaller-equal-larger than 'rs'.
- ** The code is a little tricky because it allows '\0' in the strings
- ** and it uses 'strcoll' (to respect locales) for each segments
- ** of the strings.
- */
- static int l_strcmp (const TString *ls, const TString *rs) {
- const char *l = getstr(ls);
- size_t ll = tsslen(ls);
- const char *r = getstr(rs);
- size_t lr = tsslen(rs);
- for (;;) { /* for each segment */
- int temp = strcoll(l, r);
- if (temp != 0) /* not equal? */
- return temp; /* done */
- else { /* strings are equal up to a '\0' */
- size_t len = strlen(l); /* index of first '\0' in both strings */
- if (len == lr) /* 'rs' is finished? */
- return (len == ll) ? 0 : 1; /* check 'ls' */
- else if (len == ll) /* 'ls' is finished? */
- return -1; /* 'ls' is smaller than 'rs' ('rs' is not finished) */
- /* both strings longer than 'len'; go on comparing after the '\0' */
- len++;
- l += len; ll -= len; r += len; lr -= len;
- }
- }
- }
- /*
- ** Check whether integer 'i' is less than float 'f'. If 'i' has an
- ** exact representation as a float ('l_intfitsf'), compare numbers as
- ** floats. Otherwise, if 'f' is outside the range for integers, result
- ** is trivial. Otherwise, compare them as integers. (When 'i' has no
- ** float representation, either 'f' is "far away" from 'i' or 'f' has
- ** no precision left for a fractional part; either way, how 'f' is
- ** truncated is irrelevant.) When 'f' is NaN, comparisons must result
- ** in false.
- */
- static int LTintfloat (lua_Integer i, lua_Number f) {
- #if defined(l_intfitsf)
- if (!l_intfitsf(i)) {
- if (f >= -cast_num(LUA_MININTEGER)) /* -minint == maxint + 1 */
- return 1; /* f >= maxint + 1 > i */
- else if (f > cast_num(LUA_MININTEGER)) /* minint < f <= maxint ? */
- return (i < cast(lua_Integer, f)); /* compare them as integers */
- else /* f <= minint <= i (or 'f' is NaN) --> not(i < f) */
- return 0;
- }
- #endif
- return luai_numlt(cast_num(i), f); /* compare them as floats */
- }
- /*
- ** Check whether integer 'i' is less than or equal to float 'f'.
- ** See comments on previous function.
- */
- static int LEintfloat (lua_Integer i, lua_Number f) {
- #if defined(l_intfitsf)
- if (!l_intfitsf(i)) {
- if (f >= -cast_num(LUA_MININTEGER)) /* -minint == maxint + 1 */
- return 1; /* f >= maxint + 1 > i */
- else if (f >= cast_num(LUA_MININTEGER)) /* minint <= f <= maxint ? */
- return (i <= cast(lua_Integer, f)); /* compare them as integers */
- else /* f < minint <= i (or 'f' is NaN) --> not(i <= f) */
- return 0;
- }
- #endif
- return luai_numle(cast_num(i), f); /* compare them as floats */
- }
- /*
- ** Return 'l < r', for numbers.
- */
- static int LTnum (const TValue *l, const TValue *r) {
- if (ttisinteger(l)) {
- lua_Integer li = ivalue(l);
- if (ttisinteger(r))
- return li < ivalue(r); /* both are integers */
- else /* 'l' is int and 'r' is float */
- return LTintfloat(li, fltvalue(r)); /* l < r ? */
- }
- else {
- lua_Number lf = fltvalue(l); /* 'l' must be float */
- if (ttisfloat(r))
- return luai_numlt(lf, fltvalue(r)); /* both are float */
- else if (luai_numisnan(lf)) /* 'r' is int and 'l' is float */
- return 0; /* NaN < i is always false */
- else /* without NaN, (l < r) <--> not(r <= l) */
- return !LEintfloat(ivalue(r), lf); /* not (r <= l) ? */
- }
- }
- /*
- ** Return 'l <= r', for numbers.
- */
- static int LEnum (const TValue *l, const TValue *r) {
- if (ttisinteger(l)) {
- lua_Integer li = ivalue(l);
- if (ttisinteger(r))
- return li <= ivalue(r); /* both are integers */
- else /* 'l' is int and 'r' is float */
- return LEintfloat(li, fltvalue(r)); /* l <= r ? */
- }
- else {
- lua_Number lf = fltvalue(l); /* 'l' must be float */
- if (ttisfloat(r))
- return luai_numle(lf, fltvalue(r)); /* both are float */
- else if (luai_numisnan(lf)) /* 'r' is int and 'l' is float */
- return 0; /* NaN <= i is always false */
- else /* without NaN, (l <= r) <--> not(r < l) */
- return !LTintfloat(ivalue(r), lf); /* not (r < l) ? */
- }
- }
- /*
- ** Main operation less than; return 'l < r'.
- */
- int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) {
- int res;
- if (ttisnumber(l) && ttisnumber(r)) /* both operands are numbers? */
- return LTnum(l, r);
- else if (ttisstring(l) && ttisstring(r)) /* both are strings? */
- return l_strcmp(tsvalue(l), tsvalue(r)) < 0;
- else if ((res = luaT_callorderTM(L, l, r, TM_LT)) < 0) /* no metamethod? */
- luaG_ordererror(L, l, r); /* error */
- return res;
- }
- /*
- ** Main operation less than or equal to; return 'l <= r'. If it needs
- ** a metamethod and there is no '__le', try '__lt', based on
- ** l <= r iff !(r < l) (assuming a total order). If the metamethod
- ** yields during this substitution, the continuation has to know
- ** about it (to negate the result of r<l); bit CIST_LEQ in the call
- ** status keeps that information.
- */
- int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r) {
- int res;
- if (ttisnumber(l) && ttisnumber(r)) /* both operands are numbers? */
- return LEnum(l, r);
- else if (ttisstring(l) && ttisstring(r)) /* both are strings? */
- return l_strcmp(tsvalue(l), tsvalue(r)) <= 0;
- else if ((res = luaT_callorderTM(L, l, r, TM_LE)) >= 0) /* try 'le' */
- return res;
- else { /* try 'lt': */
- L->ci->callstatus |= CIST_LEQ; /* mark it is doing 'lt' for 'le' */
- res = luaT_callorderTM(L, r, l, TM_LT);
- L->ci->callstatus ^= CIST_LEQ; /* clear mark */
- if (res < 0)
- luaG_ordererror(L, l, r);
- return !res; /* result is negated */
- }
- }
- /*
- ** Main operation for equality of Lua values; return 't1 == t2'.
- ** L == NULL means raw equality (no metamethods)
- */
- int luaV_equalobj (lua_State *L, const TValue *t1, const TValue *t2) {
- const TValue *tm;
- if (ttype(t1) != ttype(t2)) { /* not the same variant? */
- if (ttnov(t1) != ttnov(t2) || ttnov(t1) != LUA_TNUMBER)
- return 0; /* only numbers can be equal with different variants */
- else { /* two numbers with different variants */
- lua_Integer i1, i2; /* compare them as integers */
- return (tointeger(t1, &i1) && tointeger(t2, &i2) && i1 == i2);
- }
- }
- /* values have same type and same variant */
- switch (ttype(t1)) {
- case LUA_TNIL: return 1;
- case LUA_TNUMINT: return (ivalue(t1) == ivalue(t2));
- case LUA_TNUMFLT: return luai_numeq(fltvalue(t1), fltvalue(t2));
- case LUA_TBOOLEAN: return bvalue(t1) == bvalue(t2); /* true must be 1 !! */
- case LUA_TLIGHTUSERDATA: return pvalue(t1) == pvalue(t2);
- case LUA_TLCF: return fvalue(t1) == fvalue(t2);
- case LUA_TSHRSTR: return eqshrstr(tsvalue(t1), tsvalue(t2));
- case LUA_TLNGSTR: return luaS_eqlngstr(tsvalue(t1), tsvalue(t2));
- case LUA_TUSERDATA: {
- if (uvalue(t1) == uvalue(t2)) return 1;
- else if (L == NULL) return 0;
- tm = fasttm(L, uvalue(t1)->metatable, TM_EQ);
- if (tm == NULL)
- tm = fasttm(L, uvalue(t2)->metatable, TM_EQ);
- break; /* will try TM */
- }
- case LUA_TTABLE: {
- if (hvalue(t1) == hvalue(t2)) return 1;
- else if (L == NULL) return 0;
- tm = fasttm(L, hvalue(t1)->metatable, TM_EQ);
- if (tm == NULL)
- tm = fasttm(L, hvalue(t2)->metatable, TM_EQ);
- break; /* will try TM */
- }
- default:
- return gcvalue(t1) == gcvalue(t2);
- }
- if (tm == NULL) /* no TM? */
- return 0; /* objects are different */
- luaT_callTM(L, tm, t1, t2, L->top, 1); /* call TM */
- return !l_isfalse(L->top);
- }
- /* macro used by 'luaV_concat' to ensure that element at 'o' is a string */
- #define tostring(L,o) \
- (ttisstring(o) || (cvt2str(o) && (luaO_tostring(L, o), 1)))
- #define isemptystr(o) (ttisshrstring(o) && tsvalue(o)->shrlen == 0)
- /* copy strings in stack from top - n up to top - 1 to buffer */
- static void copy2buff (StkId top, int n, char *buff) {
- size_t tl = 0; /* size already copied */
- do {
- size_t l = vslen(top - n); /* length of string being copied */
- memcpy(buff + tl, svalue(top - n), l * sizeof(char));
- tl += l;
- } while (--n > 0);
- }
- /*
- ** Main operation for concatenation: concat 'total' values in the stack,
- ** from 'L->top - total' up to 'L->top - 1'.
- */
- void luaV_concat (lua_State *L, int total) {
- lua_assert(total >= 2);
- do {
- StkId top = L->top;
- int n = 2; /* number of elements handled in this pass (at least 2) */
- if (!(ttisstring(top-2) || cvt2str(top-2)) || !tostring(L, top-1))
- luaT_trybinTM(L, top-2, top-1, top-2, TM_CONCAT);
- else if (isemptystr(top - 1)) /* second operand is empty? */
- cast_void(tostring(L, top - 2)); /* result is first operand */
- else if (isemptystr(top - 2)) { /* first operand is an empty string? */
- setobjs2s(L, top - 2, top - 1); /* result is second op. */
- }
- else {
- /* at least two non-empty string values; get as many as possible */
- size_t tl = vslen(top - 1);
- TString *ts;
- /* collect total length and number of strings */
- for (n = 1; n < total && tostring(L, top - n - 1); n++) {
- size_t l = vslen(top - n - 1);
- if (l >= (MAX_SIZE/sizeof(char)) - tl)
- luaG_runerror(L, "string length overflow");
- tl += l;
- }
- if (tl <= LUAI_MAXSHORTLEN) { /* is result a short string? */
- char buff[LUAI_MAXSHORTLEN];
- copy2buff(top, n, buff); /* copy strings to buffer */
- ts = luaS_newlstr(L, buff, tl);
- }
- else { /* long string; copy strings directly to final result */
- ts = luaS_createlngstrobj(L, tl);
- copy2buff(top, n, getstr(ts));
- }
- setsvalue2s(L, top - n, ts); /* create result */
- }
- total -= n-1; /* got 'n' strings to create 1 new */
- L->top -= n-1; /* popped 'n' strings and pushed one */
- } while (total > 1); /* repeat until only 1 result left */
- }
- /*
- ** Main operation 'ra' = #rb'.
- */
- void luaV_objlen (lua_State *L, StkId ra, const TValue *rb) {
- const TValue *tm;
- switch (ttype(rb)) {
- case LUA_TTABLE: {
- Table *h = hvalue(rb);
- tm = fasttm(L, h->metatable, TM_LEN);
- if (tm) break; /* metamethod? break switch to call it */
- setivalue(ra, luaH_getn(h)); /* else primitive len */
- return;
- }
- case LUA_TSHRSTR: {
- setivalue(ra, tsvalue(rb)->shrlen);
- return;
- }
- case LUA_TLNGSTR: {
- setivalue(ra, tsvalue(rb)->u.lnglen);
- return;
- }
- default: { /* try metamethod */
- tm = luaT_gettmbyobj(L, rb, TM_LEN);
- if (ttisnil(tm)) /* no metamethod? */
- luaG_typeerror(L, rb, "get length of");
- break;
- }
- }
- luaT_callTM(L, tm, rb, rb, ra, 1);
- }
- /*
- ** Integer division; return 'm // n', that is, floor(m/n).
- ** C division truncates its result (rounds towards zero).
- ** 'floor(q) == trunc(q)' when 'q >= 0' or when 'q' is integer,
- ** otherwise 'floor(q) == trunc(q) - 1'.
- */
- lua_Integer luaV_div (lua_State *L, lua_Integer m, lua_Integer n) {
- if (l_castS2U(n) + 1u <= 1u) { /* special cases: -1 or 0 */
- if (n == 0)
- luaG_runerror(L, "attempt to divide by zero");
- return intop(-, 0, m); /* n==-1; avoid overflow with 0x80000...//-1 */
- }
- else {
- lua_Integer q = m / n; /* perform C division */
- if ((m ^ n) < 0 && m % n != 0) /* 'm/n' would be negative non-integer? */
- q -= 1; /* correct result for different rounding */
- return q;
- }
- }
- /*
- ** Integer modulus; return 'm % n'. (Assume that C '%' with
- ** negative operands follows C99 behavior. See previous comment
- ** about luaV_div.)
- */
- lua_Integer luaV_mod (lua_State *L, lua_Integer m, lua_Integer n) {
- if (l_castS2U(n) + 1u <= 1u) { /* special cases: -1 or 0 */
- if (n == 0)
- luaG_runerror(L, "attempt to perform 'n%%0'");
- return 0; /* m % -1 == 0; avoid overflow with 0x80000...%-1 */
- }
- else {
- lua_Integer r = m % n;
- if (r != 0 && (m ^ n) < 0) /* 'm/n' would be non-integer negative? */
- r += n; /* correct result for different rounding */
- return r;
- }
- }
- /* number of bits in an integer */
- #define NBITS cast_int(sizeof(lua_Integer) * CHAR_BIT)
- /*
- ** Shift left operation. (Shift right just negates 'y'.)
- */
- lua_Integer luaV_shiftl (lua_Integer x, lua_Integer y) {
- if (y < 0) { /* shift right? */
- if (y <= -NBITS) return 0;
- else return intop(>>, x, -y);
- }
- else { /* shift left */
- if (y >= NBITS) return 0;
- else return intop(<<, x, y);
- }
- }
- /*
- ** check whether cached closure in prototype 'p' may be reused, that is,
- ** whether there is a cached closure with the same upvalues needed by
- ** new closure to be created.
- */
- static LClosure *getcached (Proto *p, UpVal **encup, StkId base) {
- LClosure *c = p->cache;
- if (c != NULL) { /* is there a cached closure? */
- int nup = p->sizeupvalues;
- Upvaldesc *uv = p->upvalues;
- int i;
- for (i = 0; i < nup; i++) { /* check whether it has right upvalues */
- TValue *v = uv[i].instack ? base + uv[i].idx : encup[uv[i].idx]->v;
- if (c->upvals[i]->v != v)
- return NULL; /* wrong upvalue; cannot reuse closure */
- }
- }
- return c; /* return cached closure (or NULL if no cached closure) */
- }
- /*
- ** create a new Lua closure, push it in the stack, and initialize
- ** its upvalues. Note that the closure is not cached if prototype is
- ** already black (which means that 'cache' was already cleared by the
- ** GC).
- */
- static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base,
- StkId ra) {
- int nup = p->sizeupvalues;
- Upvaldesc *uv = p->upvalues;
- int i;
- LClosure *ncl = luaF_newLclosure(L, nup);
- ncl->p = p;
- setclLvalue(L, ra, ncl); /* anchor new closure in stack */
- for (i = 0; i < nup; i++) { /* fill in its upvalues */
- if (uv[i].instack) /* upvalue refers to local variable? */
- ncl->upvals[i] = luaF_findupval(L, base + uv[i].idx);
- else /* get upvalue from enclosing function */
- ncl->upvals[i] = encup[uv[i].idx];
- ncl->upvals[i]->refcount++;
- /* new closure is white, so we do not need a barrier here */
- }
- if (!isblack(p)) /* cache will not break GC invariant? */
- p->cache = ncl; /* save it on cache for reuse */
- }
- /*
- ** finish execution of an opcode interrupted by an yield
- */
- void luaV_finishOp (lua_State *L) {
- CallInfo *ci = L->ci;
- StkId base = ci->u.l.base;
- Instruction inst = *(ci->u.l.savedpc - 1); /* interrupted instruction */
- OpCode op = GET_OPCODE(inst);
- switch (op) { /* finish its execution */
- case OP_ADD: case OP_SUB: case OP_MUL: case OP_DIV: case OP_IDIV:
- case OP_BAND: case OP_BOR: case OP_BXOR: case OP_SHL: case OP_SHR:
- case OP_MOD: case OP_POW:
- case OP_UNM: case OP_BNOT: case OP_LEN:
- case OP_GETTABUP: case OP_GETTABLE: case OP_SELF: {
- setobjs2s(L, base + GETARG_A(inst), --L->top);
- break;
- }
- case OP_LE: case OP_LT: case OP_EQ: {
- int res = !l_isfalse(L->top - 1);
- L->top--;
- if (ci->callstatus & CIST_LEQ) { /* "<=" using "<" instead? */
- lua_assert(op == OP_LE);
- ci->callstatus ^= CIST_LEQ; /* clear mark */
- res = !res; /* negate result */
- }
- lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_JMP);
- if (res != GETARG_A(inst)) /* condition failed? */
- ci->u.l.savedpc++; /* skip jump instruction */
- break;
- }
- case OP_CONCAT: {
- StkId top = L->top - 1; /* top when 'luaT_trybinTM' was called */
- int b = GETARG_B(inst); /* first element to concatenate */
- int total = cast_int(top - 1 - (base + b)); /* yet to concatenate */
- setobj2s(L, top - 2, top); /* put TM result in proper position */
- if (total > 1) { /* are there elements to concat? */
- L->top = top - 1; /* top is one after last element (at top-2) */
- luaV_concat(L, total); /* concat them (may yield again) */
- }
- /* move final result to final position */
- setobj2s(L, ci->u.l.base + GETARG_A(inst), L->top - 1);
- L->top = ci->top; /* restore top */
- break;
- }
- case OP_TFORCALL: {
- lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_TFORLOOP);
- L->top = ci->top; /* correct top */
- break;
- }
- case OP_CALL: {
- if (GETARG_C(inst) - 1 >= 0) /* nresults >= 0? */
- L->top = ci->top; /* adjust results */
- break;
- }
- case OP_TAILCALL: case OP_SETTABUP: case OP_SETTABLE:
- break;
- default: lua_assert(0);
- }
- }
- /*
- ** {==================================================================
- ** Function 'luaV_execute': main interpreter loop
- ** ===================================================================
- */
- /*
- ** some macros for common tasks in 'luaV_execute'
- */
- #define RA(i) (base+GETARG_A(i))
- #define RB(i) check_exp(getBMode(GET_OPCODE(i)) == OpArgR, base+GETARG_B(i))
- #define RC(i) check_exp(getCMode(GET_OPCODE(i)) == OpArgR, base+GETARG_C(i))
- #define RKB(i) check_exp(getBMode(GET_OPCODE(i)) == OpArgK, \
- ISK(GETARG_B(i)) ? k+INDEXK(GETARG_B(i)) : base+GETARG_B(i))
- #define RKC(i) check_exp(getCMode(GET_OPCODE(i)) == OpArgK, \
- ISK(GETARG_C(i)) ? k+INDEXK(GETARG_C(i)) : base+GETARG_C(i))
- /* execute a jump instruction */
- #define dojump(ci,i,e) \
- { int a = GETARG_A(i); \
- if (a != 0) luaF_close(L, ci->u.l.base + a - 1); \
- ci->u.l.savedpc += GETARG_sBx(i) + e; }
- /* for test instructions, execute the jump instruction that follows it */
- #define donextjump(ci) { i = *ci->u.l.savedpc; dojump(ci, i, 1); }
- #define Protect(x) { {x;}; base = ci->u.l.base; }
- #define checkGC(L,c) \
- { luaC_condGC(L, L->top = (c), /* limit of live values */ \
- Protect(L->top = ci->top)); /* restore top */ \
- luai_threadyield(L); }
- /* fetch an instruction and prepare its execution */
- #define vmfetch() { \
- i = *(ci->u.l.savedpc++); \
- if (L->hookmask & (LUA_MASKLINE | LUA_MASKCOUNT)) \
- Protect(luaG_traceexec(L)); \
- ra = RA(i); /* WARNING: any stack reallocation invalidates 'ra' */ \
- lua_assert(base == ci->u.l.base); \
- lua_assert(base <= L->top && L->top < L->stack + L->stacksize); \
- }
- #define vmdispatch(o) switch(o)
- #define vmcase(l) case l:
- #define vmbreak break
- /*
- ** copy of 'luaV_gettable', but protecting the call to potential
- ** metamethod (which can reallocate the stack)
- */
- #define gettableProtected(L,t,k,v) { const TValue *slot; \
- if (luaV_fastget(L,t,k,slot,luaH_get)) { setobj2s(L, v, slot); } \
- else Protect(luaV_finishget(L,t,k,v,slot)); }
- /* same for 'luaV_settable' */
- #define settableProtected(L,t,k,v) { const TValue *slot; \
- if (!luaV_fastset(L,t,k,slot,luaH_get,v)) \
- Protect(luaV_finishset(L,t,k,v,slot)); }
- void luaV_execute (lua_State *L) {
- CallInfo *ci = L->ci;
- LClosure *cl;
- TValue *k;
- StkId base;
- ci->callstatus |= CIST_FRESH; /* fresh invocation of 'luaV_execute" */
- newframe: /* reentry point when frame changes (call/return) */
- lua_assert(ci == L->ci);
- cl = clLvalue(ci->func); /* local reference to function's closure */
- k = cl->p->k; /* local reference to function's constant table */
- base = ci->u.l.base; /* local copy of function's base */
- /* main loop of interpreter */
- for (;;) {
- Instruction i;
- StkId ra;
- vmfetch();
- vmdispatch (GET_OPCODE(i)) {
- vmcase(OP_MOVE) {
- setobjs2s(L, ra, RB(i));
- vmbreak;
- }
- vmcase(OP_LOADK) {
- TValue *rb = k + GETARG_Bx(i);
- setobj2s(L, ra, rb);
- vmbreak;
- }
- vmcase(OP_LOADKX) {
- TValue *rb;
- lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_EXTRAARG);
- rb = k + GETARG_Ax(*ci->u.l.savedpc++);
- setobj2s(L, ra, rb);
- vmbreak;
- }
- vmcase(OP_LOADBOOL) {
- setbvalue(ra, GETARG_B(i));
- if (GETARG_C(i)) ci->u.l.savedpc++; /* skip next instruction (if C) */
- vmbreak;
- }
- vmcase(OP_LOADNIL) {
- int b = GETARG_B(i);
- do {
- setnilvalue(ra++);
- } while (b--);
- vmbreak;
- }
- vmcase(OP_GETUPVAL) {
- int b = GETARG_B(i);
- setobj2s(L, ra, cl->upvals[b]->v);
- vmbreak;
- }
- vmcase(OP_GETTABUP) {
- TValue *upval = cl->upvals[GETARG_B(i)]->v;
- TValue *rc = RKC(i);
- gettableProtected(L, upval, rc, ra);
- vmbreak;
- }
- vmcase(OP_GETTABLE) {
- StkId rb = RB(i);
- TValue *rc = RKC(i);
- gettableProtected(L, rb, rc, ra);
- vmbreak;
- }
- vmcase(OP_SETTABUP) {
- TValue *upval = cl->upvals[GETARG_A(i)]->v;
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- settableProtected(L, upval, rb, rc);
- vmbreak;
- }
- vmcase(OP_SETUPVAL) {
- UpVal *uv = cl->upvals[GETARG_B(i)];
- setobj(L, uv->v, ra);
- luaC_upvalbarrier(L, uv);
- vmbreak;
- }
- vmcase(OP_SETTABLE) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- settableProtected(L, ra, rb, rc);
- vmbreak;
- }
- vmcase(OP_NEWTABLE) {
- int b = GETARG_B(i);
- int c = GETARG_C(i);
- Table *t = luaH_new(L);
- sethvalue(L, ra, t);
- if (b != 0 || c != 0)
- luaH_resize(L, t, luaO_fb2int(b), luaO_fb2int(c));
- checkGC(L, ra + 1);
- vmbreak;
- }
- vmcase(OP_SELF) {
- const TValue *aux;
- StkId rb = RB(i);
- TValue *rc = RKC(i);
- TString *key = tsvalue(rc); /* key must be a string */
- setobjs2s(L, ra + 1, rb);
- if (luaV_fastget(L, rb, key, aux, luaH_getstr)) {
- setobj2s(L, ra, aux);
- }
- else Protect(luaV_finishget(L, rb, rc, ra, aux));
- vmbreak;
- }
- vmcase(OP_ADD) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Number nb; lua_Number nc;
- if (ttisinteger(rb) && ttisinteger(rc)) {
- lua_Integer ib = ivalue(rb); lua_Integer ic = ivalue(rc);
- setivalue(ra, intop(+, ib, ic));
- }
- else if (tonumber(rb, &nb) && tonumber(rc, &nc)) {
- setfltvalue(ra, luai_numadd(L, nb, nc));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_ADD)); }
- vmbreak;
- }
- vmcase(OP_SUB) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Number nb; lua_Number nc;
- if (ttisinteger(rb) && ttisinteger(rc)) {
- lua_Integer ib = ivalue(rb); lua_Integer ic = ivalue(rc);
- setivalue(ra, intop(-, ib, ic));
- }
- else if (tonumber(rb, &nb) && tonumber(rc, &nc)) {
- setfltvalue(ra, luai_numsub(L, nb, nc));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_SUB)); }
- vmbreak;
- }
- vmcase(OP_MUL) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Number nb; lua_Number nc;
- if (ttisinteger(rb) && ttisinteger(rc)) {
- lua_Integer ib = ivalue(rb); lua_Integer ic = ivalue(rc);
- setivalue(ra, intop(*, ib, ic));
- }
- else if (tonumber(rb, &nb) && tonumber(rc, &nc)) {
- setfltvalue(ra, luai_nummul(L, nb, nc));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_MUL)); }
- vmbreak;
- }
- vmcase(OP_DIV) { /* float division (always with floats) */
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Number nb; lua_Number nc;
- if (tonumber(rb, &nb) && tonumber(rc, &nc)) {
- setfltvalue(ra, luai_numdiv(L, nb, nc));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_DIV)); }
- vmbreak;
- }
- vmcase(OP_BAND) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Integer ib; lua_Integer ic;
- if (tointeger(rb, &ib) && tointeger(rc, &ic)) {
- setivalue(ra, intop(&, ib, ic));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_BAND)); }
- vmbreak;
- }
- vmcase(OP_BOR) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Integer ib; lua_Integer ic;
- if (tointeger(rb, &ib) && tointeger(rc, &ic)) {
- setivalue(ra, intop(|, ib, ic));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_BOR)); }
- vmbreak;
- }
- vmcase(OP_BXOR) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Integer ib; lua_Integer ic;
- if (tointeger(rb, &ib) && tointeger(rc, &ic)) {
- setivalue(ra, intop(^, ib, ic));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_BXOR)); }
- vmbreak;
- }
- vmcase(OP_SHL) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Integer ib; lua_Integer ic;
- if (tointeger(rb, &ib) && tointeger(rc, &ic)) {
- setivalue(ra, luaV_shiftl(ib, ic));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_SHL)); }
- vmbreak;
- }
- vmcase(OP_SHR) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Integer ib; lua_Integer ic;
- if (tointeger(rb, &ib) && tointeger(rc, &ic)) {
- setivalue(ra, luaV_shiftl(ib, -ic));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_SHR)); }
- vmbreak;
- }
- vmcase(OP_MOD) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Number nb; lua_Number nc;
- if (ttisinteger(rb) && ttisinteger(rc)) {
- lua_Integer ib = ivalue(rb); lua_Integer ic = ivalue(rc);
- setivalue(ra, luaV_mod(L, ib, ic));
- }
- else if (tonumber(rb, &nb) && tonumber(rc, &nc)) {
- lua_Number m;
- luai_nummod(L, nb, nc, m);
- setfltvalue(ra, m);
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_MOD)); }
- vmbreak;
- }
- vmcase(OP_IDIV) { /* floor division */
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Number nb; lua_Number nc;
- if (ttisinteger(rb) && ttisinteger(rc)) {
- lua_Integer ib = ivalue(rb); lua_Integer ic = ivalue(rc);
- setivalue(ra, luaV_div(L, ib, ic));
- }
- else if (tonumber(rb, &nb) && tonumber(rc, &nc)) {
- setfltvalue(ra, luai_numidiv(L, nb, nc));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_IDIV)); }
- vmbreak;
- }
- vmcase(OP_POW) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- lua_Number nb; lua_Number nc;
- if (tonumber(rb, &nb) && tonumber(rc, &nc)) {
- setfltvalue(ra, luai_numpow(L, nb, nc));
- }
- else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_POW)); }
- vmbreak;
- }
- vmcase(OP_UNM) {
- TValue *rb = RB(i);
- lua_Number nb;
- if (ttisinteger(rb)) {
- lua_Integer ib = ivalue(rb);
- setivalue(ra, intop(-, 0, ib));
- }
- else if (tonumber(rb, &nb)) {
- setfltvalue(ra, luai_numunm(L, nb));
- }
- else {
- Protect(luaT_trybinTM(L, rb, rb, ra, TM_UNM));
- }
- vmbreak;
- }
- vmcase(OP_BNOT) {
- TValue *rb = RB(i);
- lua_Integer ib;
- if (tointeger(rb, &ib)) {
- setivalue(ra, intop(^, ~l_castS2U(0), ib));
- }
- else {
- Protect(luaT_trybinTM(L, rb, rb, ra, TM_BNOT));
- }
- vmbreak;
- }
- vmcase(OP_NOT) {
- TValue *rb = RB(i);
- int res = l_isfalse(rb); /* next assignment may change this value */
- setbvalue(ra, res);
- vmbreak;
- }
- vmcase(OP_LEN) {
- Protect(luaV_objlen(L, ra, RB(i)));
- vmbreak;
- }
- vmcase(OP_CONCAT) {
- int b = GETARG_B(i);
- int c = GETARG_C(i);
- StkId rb;
- L->top = base + c + 1; /* mark the end of concat operands */
- Protect(luaV_concat(L, c - b + 1));
- ra = RA(i); /* 'luaV_concat' may invoke TMs and move the stack */
- rb = base + b;
- setobjs2s(L, ra, rb);
- checkGC(L, (ra >= rb ? ra + 1 : rb));
- L->top = ci->top; /* restore top */
- vmbreak;
- }
- vmcase(OP_JMP) {
- dojump(ci, i, 0);
- vmbreak;
- }
- vmcase(OP_EQ) {
- TValue *rb = RKB(i);
- TValue *rc = RKC(i);
- Protect(
- if (luaV_equalobj(L, rb, rc) != GETARG_A(i))
- ci->u.l.savedpc++;
- else
- donextjump(ci);
- )
- vmbreak;
- }
- vmcase(OP_LT) {
- Protect(
- if (luaV_lessthan(L, RKB(i), RKC(i)) != GETARG_A(i))
- ci->u.l.savedpc++;
- else
- donextjump(ci);
- )
- vmbreak;
- }
- vmcase(OP_LE) {
- Protect(
- if (luaV_lessequal(L, RKB(i), RKC(i)) != GETARG_A(i))
- ci->u.l.savedpc++;
- else
- donextjump(ci);
- )
- vmbreak;
- }
- vmcase(OP_TEST) {
- if (GETARG_C(i) ? l_isfalse(ra) : !l_isfalse(ra))
- ci->u.l.savedpc++;
- else
- donextjump(ci);
- vmbreak;
- }
- vmcase(OP_TESTSET) {
- TValue *rb = RB(i);
- if (GETARG_C(i) ? l_isfalse(rb) : !l_isfalse(rb))
- ci->u.l.savedpc++;
- else {
- setobjs2s(L, ra, rb);
- donextjump(ci);
- }
- vmbreak;
- }
- vmcase(OP_CALL) {
- int b = GETARG_B(i);
- int nresults = GETARG_C(i) - 1;
- if (b != 0) L->top = ra+b; /* else previous instruction set top */
- if (luaD_precall(L, ra, nresults)) { /* C function? */
- if (nresults >= 0)
- L->top = ci->top; /* adjust results */
- Protect((void)0); /* update 'base' */
- }
- else { /* Lua function */
- ci = L->ci;
- goto newframe; /* restart luaV_execute over new Lua function */
- }
- vmbreak;
- }
- vmcase(OP_TAILCALL) {
- int b = GETARG_B(i);
- if (b != 0) L->top = ra+b; /* else previous instruction set top */
- lua_assert(GETARG_C(i) - 1 == LUA_MULTRET);
- if (luaD_precall(L, ra, LUA_MULTRET)) { /* C function? */
- Protect((void)0); /* update 'base' */
- }
- else {
- /* tail call: put called frame (n) in place of caller one (o) */
- CallInfo *nci = L->ci; /* called frame */
- CallInfo *oci = nci->previous; /* caller frame */
- StkId nfunc = nci->func; /* called function */
- StkId ofunc = oci->func; /* caller function */
- /* last stack slot filled by 'precall' */
- StkId lim = nci->u.l.base + getproto(nfunc)->numparams;
- int aux;
- /* close all upvalues from previous call */
- if (cl->p->sizep > 0) luaF_close(L, oci->u.l.base);
- /* move new frame into old one */
- for (aux = 0; nfunc + aux < lim; aux++)
- setobjs2s(L, ofunc + aux, nfunc + aux);
- oci->u.l.base = ofunc + (nci->u.l.base - nfunc); /* correct base */
- oci->top = L->top = ofunc + (L->top - nfunc); /* correct top */
- oci->u.l.savedpc = nci->u.l.savedpc;
- oci->callstatus |= CIST_TAIL; /* function was tail called */
- ci = L->ci = oci; /* remove new frame */
- lua_assert(L->top == oci->u.l.base + getproto(ofunc)->maxstacksize);
- goto newframe; /* restart luaV_execute over new Lua function */
- }
- vmbreak;
- }
- vmcase(OP_RETURN) {
- int b = GETARG_B(i);
- if (cl->p->sizep > 0) luaF_close(L, base);
- b = luaD_poscall(L, ci, ra, (b != 0 ? b - 1 : cast_int(L->top - ra)));
- if (ci->callstatus & CIST_FRESH) /* local 'ci' still from callee */
- return; /* external invocation: return */
- else { /* invocation via reentry: continue execution */
- ci = L->ci;
- if (b) L->top = ci->top;
- lua_assert(isLua(ci));
- lua_assert(GET_OPCODE(*((ci)->u.l.savedpc - 1)) == OP_CALL);
- goto newframe; /* restart luaV_execute over new Lua function */
- }
- }
- vmcase(OP_FORLOOP) {
- if (ttisinteger(ra)) { /* integer loop? */
- lua_Integer step = ivalue(ra + 2);
- lua_Integer idx = intop(+, ivalue(ra), step); /* increment index */
- lua_Integer limit = ivalue(ra + 1);
- if ((0 < step) ? (idx <= limit) : (limit <= idx)) {
- ci->u.l.savedpc += GETARG_sBx(i); /* jump back */
- chgivalue(ra, idx); /* update internal index... */
- setivalue(ra + 3, idx); /* ...and external index */
- }
- }
- else { /* floating loop */
- lua_Number step = fltvalue(ra + 2);
- lua_Number idx = luai_numadd(L, fltvalue(ra), step); /* inc. index */
- lua_Number limit = fltvalue(ra + 1);
- if (luai_numlt(0, step) ? luai_numle(idx, limit)
- : luai_numle(limit, idx)) {
- ci->u.l.savedpc += GETARG_sBx(i); /* jump back */
- chgfltvalue(ra, idx); /* update internal index... */
- setfltvalue(ra + 3, idx); /* ...and external index */
- }
- }
- vmbreak;
- }
- vmcase(OP_FORPREP) {
- TValue *init = ra;
- TValue *plimit = ra + 1;
- TValue *pstep = ra + 2;
- lua_Integer ilimit;
- int stopnow;
- if (ttisinteger(init) && ttisinteger(pstep) &&
- forlimit(plimit, &ilimit, ivalue(pstep), &stopnow)) {
- /* all values are integer */
- lua_Integer initv = (stopnow ? 0 : ivalue(init));
- setivalue(plimit, ilimit);
- setivalue(init, intop(-, initv, ivalue(pstep)));
- }
- else { /* try making all values floats */
- lua_Number ninit; lua_Number nlimit; lua_Number nstep;
- if (!tonumber(plimit, &nlimit))
- luaG_runerror(L, "'for' limit must be a number");
- setfltvalue(plimit, nlimit);
- if (!tonumber(pstep, &nstep))
- luaG_runerror(L, "'for' step must be a number");
- setfltvalue(pstep, nstep);
- if (!tonumber(init, &ninit))
- luaG_runerror(L, "'for' initial value must be a number");
- setfltvalue(init, luai_numsub(L, ninit, nstep));
- }
- ci->u.l.savedpc += GETARG_sBx(i);
- vmbreak;
- }
- vmcase(OP_TFORCALL) {
- StkId cb = ra + 3; /* call base */
- setobjs2s(L, cb+2, ra+2);
- setobjs2s(L, cb+1, ra+1);
- setobjs2s(L, cb, ra);
- L->top = cb + 3; /* func. + 2 args (state and index) */
- Protect(luaD_call(L, cb, GETARG_C(i)));
- L->top = ci->top;
- i = *(ci->u.l.savedpc++); /* go to next instruction */
- ra = RA(i);
- lua_assert(GET_OPCODE(i) == OP_TFORLOOP);
- goto l_tforloop;
- }
- vmcase(OP_TFORLOOP) {
- l_tforloop:
- if (!ttisnil(ra + 1)) { /* continue loop? */
- setobjs2s(L, ra, ra + 1); /* save control variable */
- ci->u.l.savedpc += GETARG_sBx(i); /* jump back */
- }
- vmbreak;
- }
- vmcase(OP_SETLIST) {
- int n = GETARG_B(i);
- int c = GETARG_C(i);
- unsigned int last;
- Table *h;
- if (n == 0) n = cast_int(L->top - ra) - 1;
- if (c == 0) {
- lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_EXTRAARG);
- c = GETARG_Ax(*ci->u.l.savedpc++);
- }
- h = hvalue(ra);
- last = ((c-1)*LFIELDS_PER_FLUSH) + n;
- if (last > h->sizearray) /* needs more space? */
- luaH_resizearray(L, h, last); /* preallocate it at once */
- for (; n > 0; n--) {
- TValue *val = ra+n;
- luaH_setint(L, h, last--, val);
- luaC_barrierback(L, h, val);
- }
- L->top = ci->top; /* correct top (in case of previous open call) */
- vmbreak;
- }
- vmcase(OP_CLOSURE) {
- Proto *p = cl->p->p[GETARG_Bx(i)];
- LClosure *ncl = getcached(p, cl->upvals, base); /* cached closure */
- if (ncl == NULL) /* no match? */
- pushclosure(L, p, cl->upvals, base, ra); /* create a new one */
- else
- setclLvalue(L, ra, ncl); /* push cashed closure */
- checkGC(L, ra + 1);
- vmbreak;
- }
- vmcase(OP_VARARG) {
- int b = GETARG_B(i) - 1; /* required results */
- int j;
- int n = cast_int(base - ci->func) - cl->p->numparams - 1;
- if (n < 0) /* less arguments than parameters? */
- n = 0; /* no vararg arguments */
- if (b < 0) { /* B == 0? */
- b = n; /* get all var. arguments */
- Protect(luaD_checkstack(L, n));
- ra = RA(i); /* previous call may change the stack */
- L->top = ra + n;
- }
- for (j = 0; j < b && j < n; j++)
- setobjs2s(L, ra + j, base - n + j);
- for (; j < b; j++) /* complete required results with nil */
- setnilvalue(ra + j);
- vmbreak;
- }
- vmcase(OP_EXTRAARG) {
- lua_assert(0);
- vmbreak;
- }
- }
- }
- }
- /* }================================================================== */
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