summaryrefslogtreecommitdiff
path: root/src/lua/lvm.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/lua/lvm.c')
-rw-r--r--src/lua/lvm.c1322
1 files changed, 1322 insertions, 0 deletions
diff --git a/src/lua/lvm.c b/src/lua/lvm.c
new file mode 100644
index 0000000..f274b05
--- /dev/null
+++ b/src/lua/lvm.c
@@ -0,0 +1,1322 @@
+/*
+** $Id: lvm.c,v 2.268.1.1 2017/04/19 17:39:34 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;
+ }
+ }
+ }
+}
+
+/* }================================================================== */
+