func binaryIntOp(x *big.Int, op token.Token, y *big.Int) interface{} {
var z big.Int
switch op {
case token.ADD:
return z.Add(x, y)
case token.SUB:
return z.Sub(x, y)
case token.MUL:
return z.Mul(x, y)
case token.QUO:
return z.Quo(x, y)
case token.REM:
return z.Rem(x, y)
case token.AND:
return z.And(x, y)
case token.OR:
return z.Or(x, y)
case token.XOR:
return z.Xor(x, y)
case token.AND_NOT:
return z.AndNot(x, y)
case token.SHL:
panic("unimplemented")
case token.SHR:
panic("unimplemented")
case token.EQL:
return x.Cmp(y) == 0
case token.NEQ:
return x.Cmp(y) != 0
case token.LSS:
return x.Cmp(y) < 0
case token.LEQ:
return x.Cmp(y) <= 0
case token.GTR:
return x.Cmp(y) > 0
case token.GEQ:
return x.Cmp(y) >= 0
}
panic("unreachable")
}