diff options
Diffstat (limited to '')
-rw-r--r-- | bruiser/lua-5.3.4/src/lvm.c | 1322 |
1 files changed, 1322 insertions, 0 deletions
diff --git a/bruiser/lua-5.3.4/src/lvm.c b/bruiser/lua-5.3.4/src/lvm.c new file mode 100644 index 0000000..84ade6b --- /dev/null +++ b/bruiser/lua-5.3.4/src/lvm.c @@ -0,0 +1,1322 @@ +/* +** $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; + } + } + } +} + +/* }================================================================== */ + |