static Instruction *getjumpcontrol (FuncState *fs, int pc) {
Instruction *pi = &fs->f->code[pc];
if (pc >= 1 && testOpMode(GET_OPCODE(*(pi-1)), OpModeT))
return pi-1;
else
return pi;
}
static Instruction luaG_symbexec (const Proto *pt, int lastpc, int reg) {
int pc;
int last; /* stores position of last instruction that changed `reg' */
last = pt->sizecode-1; /* points to final return (a `neutral' instruction) */
check(precheck(pt));
for (pc = 0; pc < lastpc; pc++) {
const Instruction i = pt->code[pc];
OpCode op = GET_OPCODE(i);
int a = GETARG_A(i);
int b = 0;
int c = 0;
checkreg(pt, a);
switch (getOpMode(op)) {
case iABC: {
b = GETARG_B(i);
c = GETARG_C(i);
if (testOpMode(op, OpModeBreg)) {
checkreg(pt, b);
}
else if (testOpMode(op, OpModeBrk))
check(checkRK(pt, b));
if (testOpMode(op, OpModeCrk))
check(checkRK(pt, c));
break;
}
case iABx: {
b = GETARG_Bx(i);
if (testOpMode(op, OpModeK)) check(b < pt->sizek);
break;
}
case iAsBx: {
b = GETARG_sBx(i);
break;
}
}
if (testOpMode(op, OpModesetA)) {
if (a == reg) last = pc; /* change register `a' */
}
if (testOpMode(op, OpModeT)) {
check(pc+2 < pt->sizecode); /* check skip */
check(GET_OPCODE(pt->code[pc+1]) == OP_JMP);
}
switch (op) {
case OP_LOADBOOL: {
check(c == 0 || pc+2 < pt->sizecode); /* check its jump */
break;
}
case OP_LOADNIL: {
if (a <= reg && reg <= b)
last = pc; /* set registers from `a' to `b' */
break;
}
case OP_GETUPVAL:
case OP_SETUPVAL: {
check(b < pt->nups);
break;
}
case OP_GETGLOBAL:
case OP_SETGLOBAL: {
check(ttisstring(&pt->k[b]));
break;
}
case OP_SELF: {
checkreg(pt, a+1);
if (reg == a+1) last = pc;
break;
}
case OP_CONCAT: {
/* `c' is a register, and at least two operands */
check(c < MAXSTACK && b < c);
break;
}
case OP_TFORLOOP:
checkreg(pt, a+c+5);
if (reg >= a) last = pc; /* affect all registers above base */
/* go through */
case OP_FORLOOP:
checkreg(pt, a+2);
/* go through */
case OP_JMP: {
int dest = pc+1+b;
check(0 <= dest && dest < pt->sizecode);
/* not full check and jump is forward and do not skip `lastpc'? */
if (reg != NO_REG && pc < dest && dest <= lastpc)
pc += b; /* do the jump */
break;
}
case OP_CALL:
case OP_TAILCALL: {
if (b != 0) {
checkreg(pt, a+b-1);
}
c--; /* c = num. returns */
if (c == LUA_MULTRET) {
check(checkopenop(pt, pc));
}
else if (c != 0)
checkreg(pt, a+c-1);
if (reg >= a) last = pc; /* affect all registers above base */
break;
}
case OP_RETURN: {
b--; /* b = num. returns */
if (b > 0) checkreg(pt, a+b-1);
break;
}
case OP_SETLIST: {
checkreg(pt, a + (b&(LFIELDS_PER_FLUSH-1)) + 1);
break;
}
case OP_CLOSURE: {
int nup;
check(b < pt->sizep);
nup = pt->p[b]->nups;
check(pc + nup < pt->sizecode);
for (; nup>0; nup--) {
OpCode op1 = GET_OPCODE(pt->code[pc+nup]);
check(op1 == OP_GETUPVAL || op1 == OP_MOVE);
}
break;
}
default: break;
}
}
return pt->code[last];
}
