/*
** $Id: lvm.c,v 2.63.1.5 2011/08/17 20:43:11 roberto Exp $
** Lua virtual machine
** See Copyright Notice in lua.h
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define lvm_c
#define LUA_CORE

#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 100

const TValue *luaV_tonumber(const TValue *obj, TValue *n)
{
    lua_Number num;
    if (ttisnumber(obj))
        return obj;
    if (ttisstring(obj) && luaO_str2d(svalue(obj), &num)) {
        setnvalue(n, num);
        return n;
    }
    else
        return NULL;
}

int luaV_tostring(lua_State *L, StkId obj)
{
    if (!ttisnumber(obj))
        return 0;
    else {
        char s[LUAI_MAXNUMBER2STR];
        lua_Number n = nvalue(obj);
        lua_number2str(s, n);
        setsvalue2s(L, obj, luaS_new(L, s));
        return 1;
    }
}

static void traceexec(lua_State *L, const Instruction *pc)
{
    lu_byte mask = L->hookmask;
    const Instruction *oldpc = L->savedpc;
    L->savedpc = pc;
    if ((mask & LUA_MASKCOUNT) && L->hookcount == 0) {
        resethookcount(L);
        luaD_callhook(L, LUA_HOOKCOUNT, -1);
    }
    if (mask & LUA_MASKLINE) {
        Proto *p = ci_func(L->ci)->l.p;
        int npc = pcRel(pc, p);
        int newline = getline(p, npc);
        /* call linehook when enter a new function, when jump back (loop),
       or when enter a new line */
        if (npc == 0 || pc <= oldpc || newline != getline(p, pcRel(oldpc, p)))
            luaD_callhook(L, LUA_HOOKLINE, newline);
    }
}

static void callTMres(lua_State *L, StkId res, const TValue *f,
                      const TValue *p1, const TValue *p2)
{
    ptrdiff_t result = savestack(L, res);
    setobj2s(L, L->top, f);      /* push function */
    setobj2s(L, L->top + 1, p1); /* 1st argument */
    setobj2s(L, L->top + 2, p2); /* 2nd argument */
    luaD_checkstack(L, 3);
    L->top += 3;
    luaD_call(L, L->top - 3, 1);
    res = restorestack(L, result);
    L->top--;
    setobjs2s(L, res, L->top);
}

static void callTM(lua_State *L, const TValue *f, const TValue *p1,
                   const TValue *p2, const TValue *p3)
{
    setobj2s(L, L->top, f);      /* push function */
    setobj2s(L, L->top + 1, p1); /* 1st argument */
    setobj2s(L, L->top + 2, p2); /* 2nd argument */
    setobj2s(L, L->top + 3, p3); /* 3th argument */
    luaD_checkstack(L, 4);
    L->top += 4;
    luaD_call(L, L->top - 4, 0);
}

void luaV_gettable(lua_State *L, const TValue *t, TValue *key, StkId val)
{
    int loop;
    for (loop = 0; loop < MAXTAGLOOP; loop++) {
        const TValue *tm;
        if (ttistable(t)) { /* `t' is a table? */
            Table *h = hvalue(t);
            const TValue *res = luaH_get(h, key); /* do a primitive get */
            if (!ttisnil(res) ||                  /* result is no nil? */
                (tm = fasttm(L, h->metatable, TM_INDEX)) ==
                    NULL) { /* or no TM? */
                setobj2s(L, val, res);
                return;
            }
            /* else will try the tag method */
        }
        else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_INDEX)))
            luaG_typeerror(L, t, "index");
        if (ttisfunction(tm)) {
            callTMres(L, val, tm, t, key);
            return;
        }
        t = tm; /* else repeat with `tm' */
    }
    luaG_runerror(L, "loop in gettable");
}

void luaV_settable(lua_State *L, const TValue *t, TValue *key, StkId val)
{
    int loop;
    TValue temp;
    for (loop = 0; loop < MAXTAGLOOP; loop++) {
        const TValue *tm;
        if (ttistable(t)) { /* `t' is a table? */
            Table *h = hvalue(t);
            TValue *oldval = luaH_set(L, h, key); /* do a primitive set */
            if (!ttisnil(oldval) ||               /* result is no nil? */
                (tm = fasttm(L, h->metatable, TM_NEWINDEX)) ==
                    NULL) { /* or no TM? */
                setobj2t(L, oldval, val);
                h->flags = 0;
                luaC_barriert(L, h, val);
                return;
            }
            /* else will try the tag method */
        }
        else if (ttisnil(tm = luaT_gettmbyobj(L, t, TM_NEWINDEX)))
            luaG_typeerror(L, t, "index");
        if (ttisfunction(tm)) {
            callTM(L, tm, t, key, val);
            return;
        }
        /* else repeat with `tm' */
        setobj(L, &temp, tm); /* avoid pointing inside table (may rehash) */
        t = &temp;
    }
    luaG_runerror(L, "loop in settable");
}

static int call_binTM(lua_State *L, const TValue *p1, const TValue *p2,
                      StkId res, TMS event)
{
    const TValue *tm = luaT_gettmbyobj(L, p1, event); /* try first operand */
    if (ttisnil(tm))
        tm = luaT_gettmbyobj(L, p2, event); /* try second operand */
    if (ttisnil(tm))
        return 0;
    callTMres(L, res, tm, p1, p2);
    return 1;
}

static const TValue *get_compTM(lua_State *L, Table *mt1, Table *mt2, TMS event)
{
    const TValue *tm1 = fasttm(L, mt1, event);
    const TValue *tm2;
    if (tm1 == NULL)
        return NULL; /* no metamethod */
    if (mt1 == mt2)
        return tm1; /* same metatables => same metamethods */
    tm2 = fasttm(L, mt2, event);
    if (tm2 == NULL)
        return NULL;                /* no metamethod */
    if (luaO_rawequalObj(tm1, tm2)) /* same metamethods? */
        return tm1;
    return NULL;
}

static int call_orderTM(lua_State *L, const TValue *p1, const TValue *p2,
                        TMS event)
{
    const TValue *tm1 = luaT_gettmbyobj(L, p1, event);
    const TValue *tm2;
    if (ttisnil(tm1))
        return -1; /* no metamethod? */
    tm2 = luaT_gettmbyobj(L, p2, event);
    if (!luaO_rawequalObj(tm1, tm2)) /* different metamethods? */
        return -1;
    callTMres(L, L->top, tm1, p1, p2);
    return !l_isfalse(L->top);
}

static int l_strcmp(const TString *ls, const TString *rs)
{
    const char *l = getstr(ls);
    size_t ll = ls->tsv.len;
    const char *r = getstr(rs);
    size_t lr = rs->tsv.len;
    for (;;) {
        int temp = strcoll(l, r);
        if (temp != 0)
            return temp;
        else {                      /* strings are equal up to a `\0' */
            size_t len = strlen(l); /* index of first `\0' in both strings */
            if (len == lr)          /* r is finished? */
                return (len == ll) ? 0 : 1;
            else if (len == ll) /* l is finished? */
                return -1; /* l is smaller than r (because r is not finished) */
            /* both strings longer than `len'; go on comparing (after the `\0') */
            len++;
            l += len;
            ll -= len;
            r += len;
            lr -= len;
        }
    }
}

int luaV_lessthan(lua_State *L, const TValue *l, const TValue *r)
{
    int res;
    if (ttype(l) != ttype(r))
        return luaG_ordererror(L, l, r);
    else if (ttisnumber(l))
        return luai_numlt(nvalue(l), nvalue(r));
    else if (ttisstring(l))
        return l_strcmp(rawtsvalue(l), rawtsvalue(r)) < 0;
    else if ((res = call_orderTM(L, l, r, TM_LT)) != -1)
        return res;
    return luaG_ordererror(L, l, r);
}

static int lessequal(lua_State *L, const TValue *l, const TValue *r)
{
    int res;
    if (ttype(l) != ttype(r))
        return luaG_ordererror(L, l, r);
    else if (ttisnumber(l))
        return luai_numle(nvalue(l), nvalue(r));
    else if (ttisstring(l))
        return l_strcmp(rawtsvalue(l), rawtsvalue(r)) <= 0;
    else if ((res = call_orderTM(L, l, r, TM_LE)) != -1) /* first try `le' */
        return res;
    else if ((res = call_orderTM(L, r, l, TM_LT)) != -1) /* else try `lt' */
        return !res;
    return luaG_ordererror(L, l, r);
}

int luaV_equalval(lua_State *L, const TValue *t1, const TValue *t2)
{
    const TValue *tm;
    lua_assert(ttype(t1) == ttype(t2));
    switch (ttype(t1)) {
    case LUA_TNIL:
        return 1;
    case LUA_TNUMBER:
        return luai_numeq(nvalue(t1), nvalue(t2));
    case LUA_TBOOLEAN:
        return bvalue(t1) == bvalue(t2); /* true must be 1 !! */
    case LUA_TLIGHTUSERDATA:
        return pvalue(t1) == pvalue(t2);
    case LUA_TUSERDATA: {
        if (uvalue(t1) == uvalue(t2))
            return 1;
        tm = get_compTM(L, uvalue(t1)->metatable, uvalue(t2)->metatable, TM_EQ);
        break; /* will try TM */
    }
    case LUA_TTABLE: {
        if (hvalue(t1) == hvalue(t2))
            return 1;
        tm = get_compTM(L, hvalue(t1)->metatable, hvalue(t2)->metatable, TM_EQ);
        break; /* will try TM */
    }
    default:
        return gcvalue(t1) == gcvalue(t2);
    }
    if (tm == NULL)
        return 0;                     /* no TM? */
    callTMres(L, L->top, tm, t1, t2); /* call TM */
    return !l_isfalse(L->top);
}

void luaV_concat(lua_State *L, int total, int last)
{
    do {
        StkId top = L->base + last + 1;
        int n = 2; /* number of elements handled in this pass (at least 2) */
        if (!(ttisstring(top - 2) || ttisnumber(top - 2)) ||
            !tostring(L, top - 1)) {
            if (!call_binTM(L, top - 2, top - 1, top - 2, TM_CONCAT))
                luaG_concaterror(L, top - 2, top - 1);
        }
        else if (tsvalue(top - 1)->len == 0) /* second op is empty? */
            (void)tostring(L, top - 2); /* result is first op (as string) */
        else {
            /* at least two string values; get as many as possible */
            size_t tl = tsvalue(top - 1)->len;
            char *buffer;
            int i;
            /* collect total length */
            for (n = 1; n < total && tostring(L, top - n - 1); n++) {
                size_t l = tsvalue(top - n - 1)->len;
                if (l >= MAX_SIZET - tl)
                    luaG_runerror(L, "string length overflow");
                tl += l;
            }
            buffer = luaZ_openspace(L, &G(L)->buff, tl);
            tl = 0;
            for (i = n; i > 0; i--) { /* concat all strings */
                size_t l = tsvalue(top - i)->len;
                memcpy(buffer + tl, svalue(top - i), l);
                tl += l;
            }
            setsvalue2s(L, top - n, luaS_newlstr(L, buffer, tl));
        }
        total -= n - 1; /* got `n' strings to create 1 new */
        last -= n - 1;
    } while (total > 1); /* repeat until only 1 result left */
}

static void Arith(lua_State *L, StkId ra, const TValue *rb, const TValue *rc,
                  TMS op)
{
    TValue tempb, tempc;
    const TValue *b, *c;
    if ((b = luaV_tonumber(rb, &tempb)) != NULL &&
        (c = luaV_tonumber(rc, &tempc)) != NULL) {
        lua_Number nb = nvalue(b), nc = nvalue(c);
        switch (op) {
        case TM_ADD:
            setnvalue(ra, luai_numadd(nb, nc));
            break;
        case TM_SUB:
            setnvalue(ra, luai_numsub(nb, nc));
            break;
        case TM_MUL:
            setnvalue(ra, luai_nummul(nb, nc));
            break;
        case TM_DIV:
            setnvalue(ra, luai_numdiv(nb, nc));
            break;
        case TM_MOD:
            setnvalue(ra, luai_nummod(nb, nc));
            break;
        case TM_POW:
            setnvalue(ra, luai_numpow(nb, nc));
            break;
        case TM_UNM:
            setnvalue(ra, luai_numunm(nb));
            break;
        default:
            lua_assert(0);
            break;
        }
    }
    else if (!call_binTM(L, rb, rc, ra, op))
        luaG_aritherror(L, rb, rc);
}

/*
** some macros for common tasks in `luaV_execute'
*/

#define runtime_check(L, c)                                                    \
    {                                                                          \
        if (!(c))                                                              \
            break;                                                             \
    }

#define RA(i) (base + GETARG_A(i))
/* to be used after possible stack reallocation */
#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))
#define KBx(i) check_exp(getBMode(GET_OPCODE(i)) == OpArgK, k + GETARG_Bx(i))

#define dojump(L, pc, i)                                                       \
    {                                                                          \
        (pc) += (i);                                                           \
        luai_threadyield(L);                                                   \
    }

#define Protect(x)                                                             \
    {                                                                          \
        L->savedpc = pc;                                                       \
        {                                                                      \
            x;                                                                 \
        };                                                                     \
        base = L->base;                                                        \
    }

#define arith_op(op, tm)                                                       \
    {                                                                          \
        TValue *rb = RKB(i);                                                   \
        TValue *rc = RKC(i);                                                   \
        if (ttisnumber(rb) && ttisnumber(rc)) {                                \
            lua_Number nb = nvalue(rb), nc = nvalue(rc);                       \
            setnvalue(ra, op(nb, nc));                                         \
        }                                                                      \
        else                                                                   \
            Protect(Arith(L, ra, rb, rc, tm));                                 \
    }

void luaV_execute(lua_State *L, int nexeccalls)
{
    LClosure *cl;
    StkId base;
    TValue *k;
    const Instruction *pc;
reentry: /* entry point */
    lua_assert(isLua(L->ci));
    pc = L->savedpc;
    cl = &clvalue(L->ci->func)->l;
    base = L->base;
    k = cl->p->k;
    /* main loop of interpreter */
    for (;;) {
        const Instruction i = *pc++;
        StkId ra;
        if ((L->hookmask & (LUA_MASKLINE | LUA_MASKCOUNT)) &&
            (--L->hookcount == 0 || L->hookmask & LUA_MASKLINE)) {
            traceexec(L, pc);
            if (L->status == LUA_YIELD) { /* did hook yield? */
                L->savedpc = pc - 1;
                return;
            }
            base = L->base;
        }
        /* warning!! several calls may realloc the stack and invalidate `ra' */
        ra = RA(i);
        lua_assert(base == L->base && L->base == L->ci->base);
        lua_assert(base <= L->top && L->top <= L->stack + L->stacksize);
        lua_assert(L->top == L->ci->top || luaG_checkopenop(i));
        switch (GET_OPCODE(i)) {
        case OP_MOVE: {
            setobjs2s(L, ra, RB(i));
            continue;
        }
        case OP_LOADK: {
            setobj2s(L, ra, KBx(i));
            continue;
        }
        case OP_LOADBOOL: {
            setbvalue(ra, GETARG_B(i));
            if (GETARG_C(i))
                pc++; /* skip next instruction (if C) */
            continue;
        }
        case OP_LOADNIL: {
            TValue *rb = RB(i);
            do {
                setnilvalue(rb--);
            } while (rb >= ra);
            continue;
        }
        case OP_GETUPVAL: {
            int b = GETARG_B(i);
            setobj2s(L, ra, cl->upvals[b]->v);
            continue;
        }
        case OP_GETGLOBAL: {
            TValue g;
            TValue *rb = KBx(i);
            sethvalue(L, &g, cl->env);
            lua_assert(ttisstring(rb));
            Protect(luaV_gettable(L, &g, rb, ra));
            continue;
        }
        case OP_GETTABLE: {
            Protect(luaV_gettable(L, RB(i), RKC(i), ra));
            continue;
        }
        case OP_SETGLOBAL: {
            TValue g;
            sethvalue(L, &g, cl->env);
            lua_assert(ttisstring(KBx(i)));
            Protect(luaV_settable(L, &g, KBx(i), ra));
            continue;
        }
        case OP_SETUPVAL: {
            UpVal *uv = cl->upvals[GETARG_B(i)];
            setobj(L, uv->v, ra);
            luaC_barrier(L, uv, ra);
            continue;
        }
        case OP_SETTABLE: {
            Protect(luaV_settable(L, ra, RKB(i), RKC(i)));
            continue;
        }
        case OP_NEWTABLE: {
            int b = GETARG_B(i);
            int c = GETARG_C(i);
            sethvalue(L, ra, luaH_new(L, luaO_fb2int(b), luaO_fb2int(c)));
            Protect(luaC_checkGC(L));
            continue;
        }
        case OP_SELF: {
            StkId rb = RB(i);
            setobjs2s(L, ra + 1, rb);
            Protect(luaV_gettable(L, rb, RKC(i), ra));
            continue;
        }
        case OP_ADD: {
            arith_op(luai_numadd, TM_ADD);
            continue;
        }
        case OP_SUB: {
            arith_op(luai_numsub, TM_SUB);
            continue;
        }
        case OP_MUL: {
            arith_op(luai_nummul, TM_MUL);
            continue;
        }
        case OP_DIV: {
            arith_op(luai_numdiv, TM_DIV);
            continue;
        }
        case OP_MOD: {
            arith_op(luai_nummod, TM_MOD);
            continue;
        }
        case OP_POW: {
            arith_op(luai_numpow, TM_POW);
            continue;
        }
        case OP_UNM: {
            TValue *rb = RB(i);
            if (ttisnumber(rb)) {
                lua_Number nb = nvalue(rb);
                setnvalue(ra, luai_numunm(nb));
            }
            else {
                Protect(Arith(L, ra, rb, rb, TM_UNM));
            }
            continue;
        }
        case OP_NOT: {
            int res =
                l_isfalse(RB(i)); /* next assignment may change this value */
            setbvalue(ra, res);
            continue;
        }
        case OP_LEN: {
            const TValue *rb = RB(i);
            switch (ttype(rb)) {
            case LUA_TTABLE: {
                setnvalue(ra, cast_num(luaH_getn(hvalue(rb))));
                break;
            }
            case LUA_TSTRING: {
                setnvalue(ra, cast_num(tsvalue(rb)->len));
                break;
            }
            default: { /* try metamethod */
                Protect(if (!call_binTM(L, rb, luaO_nilobject, ra, TM_LEN))
                            luaG_typeerror(L, rb, "get length of");)
            }
            }
            continue;
        }
        case OP_CONCAT: {
            int b = GETARG_B(i);
            int c = GETARG_C(i);
            Protect(luaV_concat(L, c - b + 1, c); luaC_checkGC(L));
            setobjs2s(L, RA(i), base + b);
            continue;
        }
        case OP_JMP: {
            dojump(L, pc, GETARG_sBx(i));
            continue;
        }
        case OP_EQ: {
            TValue *rb = RKB(i);
            TValue *rc = RKC(i);
            Protect(if (equalobj(L, rb, rc) == GETARG_A(i))
                        dojump(L, pc, GETARG_sBx(*pc));) pc++;
            continue;
        }
        case OP_LT: {
            Protect(if (luaV_lessthan(L, RKB(i), RKC(i)) == GETARG_A(i))
                        dojump(L, pc, GETARG_sBx(*pc));) pc++;
            continue;
        }
        case OP_LE: {
            Protect(if (lessequal(L, RKB(i), RKC(i)) == GETARG_A(i))
                        dojump(L, pc, GETARG_sBx(*pc));) pc++;
            continue;
        }
        case OP_TEST: {
            if (l_isfalse(ra) != GETARG_C(i))
                dojump(L, pc, GETARG_sBx(*pc));
            pc++;
            continue;
        }
        case OP_TESTSET: {
            TValue *rb = RB(i);
            if (l_isfalse(rb) != GETARG_C(i)) {
                setobjs2s(L, ra, rb);
                dojump(L, pc, GETARG_sBx(*pc));
            }
            pc++;
            continue;
        }
        case 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 */
            L->savedpc = pc;
            switch (luaD_precall(L, ra, nresults)) {
            case PCRLUA: {
                nexeccalls++;
                goto reentry; /* restart luaV_execute over new Lua function */
            }
            case PCRC: {
                /* it was a C function (`precall' called it); adjust results */
                if (nresults >= 0)
                    L->top = L->ci->top;
                base = L->base;
                continue;
            }
            default: {
                return; /* yield */
            }
            }
        }
        case OP_TAILCALL: {
            int b = GETARG_B(i);
            if (b != 0)
                L->top = ra + b; /* else previous instruction set top */
            L->savedpc = pc;
            lua_assert(GETARG_C(i) - 1 == LUA_MULTRET);
            switch (luaD_precall(L, ra, LUA_MULTRET)) {
            case PCRLUA: {
                /* tail call: put new frame in place of previous one */
                CallInfo *ci = L->ci - 1; /* previous frame */
                int aux;
                StkId func = ci->func;
                StkId pfunc = (ci + 1)->func; /* previous function index */
                if (L->openupval)
                    luaF_close(L, ci->base);
                L->base = ci->base = ci->func + ((ci + 1)->base - pfunc);
                for (aux = 0; pfunc + aux < L->top; aux++) /* move frame down */
                    setobjs2s(L, func + aux, pfunc + aux);
                ci->top = L->top = func + aux; /* correct top */
                lua_assert(L->top ==
                           L->base + clvalue(func)->l.p->maxstacksize);
                ci->savedpc = L->savedpc;
                ci->tailcalls++; /* one more call lost */
                L->ci--;         /* remove new frame */
                goto reentry;
            }
            case PCRC: { /* it was a C function (`precall' called it) */
                base = L->base;
                continue;
            }
            default: {
                return; /* yield */
            }
            }
        }
        case OP_RETURN: {
            int b = GETARG_B(i);
            if (b != 0)
                L->top = ra + b - 1;
            if (L->openupval)
                luaF_close(L, base);
            L->savedpc = pc;
            b = luaD_poscall(L, ra);
            if (--nexeccalls == 0) /* was previous function running `here'? */
                return;            /* no: return */
            else {                 /* yes: continue its execution */
                if (b)
                    L->top = L->ci->top;
                lua_assert(isLua(L->ci));
                lua_assert(GET_OPCODE(*((L->ci)->savedpc - 1)) == OP_CALL);
                goto reentry;
            }
        }
        case OP_FORLOOP: {
            lua_Number step = nvalue(ra + 2);
            lua_Number idx =
                luai_numadd(nvalue(ra), step); /* increment index */
            lua_Number limit = nvalue(ra + 1);
            if (luai_numlt(0, step) ? luai_numle(idx, limit)
                                    : luai_numle(limit, idx)) {
                dojump(L, pc, GETARG_sBx(i)); /* jump back */
                setnvalue(ra, idx);           /* update internal index... */
                setnvalue(ra + 3, idx);       /* ...and external index */
            }
            continue;
        }
        case OP_FORPREP: {
            const TValue *init = ra;
            const TValue *plimit = ra + 1;
            const TValue *pstep = ra + 2;
            L->savedpc = pc; /* next steps may throw errors */
            if (!tonumber(init, ra))
                luaG_runerror(L,
                              LUA_QL("for") " initial value must be a number");
            else if (!tonumber(plimit, ra + 1))
                luaG_runerror(L, LUA_QL("for") " limit must be a number");
            else if (!tonumber(pstep, ra + 2))
                luaG_runerror(L, LUA_QL("for") " step must be a number");
            setnvalue(ra, luai_numsub(nvalue(ra), nvalue(pstep)));
            dojump(L, pc, GETARG_sBx(i));
            continue;
        }
        case OP_TFORLOOP: {
            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 = L->ci->top;
            cb = RA(i) + 3;     /* previous call may change the stack */
            if (!ttisnil(cb)) { /* continue loop? */
                setobjs2s(L, cb - 1, cb);       /* save control variable */
                dojump(L, pc, GETARG_sBx(*pc)); /* jump back */
            }
            pc++;
            continue;
        }
        case OP_SETLIST: {
            int n = GETARG_B(i);
            int c = GETARG_C(i);
            int last;
            Table *h;
            if (n == 0) {
                n = cast_int(L->top - ra) - 1;
                L->top = L->ci->top;
            }
            if (c == 0)
                c = cast_int(*pc++);
            runtime_check(L, ttistable(ra));
            h = hvalue(ra);
            last = ((c - 1) * LFIELDS_PER_FLUSH) + n;
            if (last > h->sizearray)          /* needs more space? */
                luaH_resizearray(L, h, last); /* pre-alloc it at once */
            for (; n > 0; n--) {
                TValue *val = ra + n;
                setobj2t(L, luaH_setnum(L, h, last--), val);
                luaC_barriert(L, h, val);
            }
            continue;
        }
        case OP_CLOSE: {
            luaF_close(L, ra);
            continue;
        }
        case OP_CLOSURE: {
            Proto *p;
            Closure *ncl;
            int nup, j;
            p = cl->p->p[GETARG_Bx(i)];
            nup = p->nups;
            ncl = luaF_newLclosure(L, nup, cl->env);
            ncl->l.p = p;
            for (j = 0; j < nup; j++, pc++) {
                if (GET_OPCODE(*pc) == OP_GETUPVAL)
                    ncl->l.upvals[j] = cl->upvals[GETARG_B(*pc)];
                else {
                    lua_assert(GET_OPCODE(*pc) == OP_MOVE);
                    ncl->l.upvals[j] = luaF_findupval(L, base + GETARG_B(*pc));
                }
            }
            setclvalue(L, ra, ncl);
            Protect(luaC_checkGC(L));
            continue;
        }
        case OP_VARARG: {
            int b = GETARG_B(i) - 1;
            int j;
            CallInfo *ci = L->ci;
            int n = cast_int(ci->base - ci->func) - cl->p->numparams - 1;
            if (b == LUA_MULTRET) {
                Protect(luaD_checkstack(L, n));
                ra = RA(i); /* previous call may change the stack */
                b = n;
                L->top = ra + n;
            }
            for (j = 0; j < b; j++) {
                if (j < n) {
                    setobjs2s(L, ra + j, ci->base - n + j);
                }
                else {
                    setnilvalue(ra + j);
                }
            }
            continue;
        }
        }
    }
}
