rust/src/primval.rs
2016-03-17 03:12:15 -06:00

73 lines
2.2 KiB
Rust

use rustc::mir::repr as mir;
#[derive(Clone, Copy, Debug, PartialEq)]
pub enum PrimVal {
Bool(bool),
I8(i8), I16(i16), I32(i32), I64(i64),
U8(u8), U16(u16), U32(u32), U64(u64),
}
pub fn binary_op(bin_op: mir::BinOp, left: PrimVal, right: PrimVal) -> PrimVal {
macro_rules! int_binops {
($v:ident, $l:ident, $r:ident) => ({
use rustc::mir::repr::BinOp::*;
use self::PrimVal::*;
match bin_op {
Add => $v($l + $r),
Sub => $v($l - $r),
Mul => $v($l * $r),
Div => $v($l / $r),
Rem => $v($l % $r),
BitXor => $v($l ^ $r),
BitAnd => $v($l & $r),
BitOr => $v($l | $r),
// TODO(tsion): Can have differently-typed RHS.
Shl => $v($l << $r),
Shr => $v($l >> $r),
Eq => Bool($l == $r),
Ne => Bool($l != $r),
Lt => Bool($l < $r),
Le => Bool($l <= $r),
Gt => Bool($l > $r),
Ge => Bool($l >= $r),
}
})
}
use self::PrimVal::*;
match (left, right) {
(I8(l), I8(r)) => int_binops!(I8, l, r),
(I16(l), I16(r)) => int_binops!(I16, l, r),
(I32(l), I32(r)) => int_binops!(I32, l, r),
(I64(l), I64(r)) => int_binops!(I64, l, r),
(U8(l), U8(r)) => int_binops!(U8, l, r),
(U16(l), U16(r)) => int_binops!(U16, l, r),
(U32(l), U32(r)) => int_binops!(U32, l, r),
(U64(l), U64(r)) => int_binops!(U64, l, r),
_ => unimplemented!(),
}
}
pub fn unary_op(un_op: mir::UnOp, val: PrimVal) -> PrimVal {
use rustc::mir::repr::UnOp::*;
use self::PrimVal::*;
match (un_op, val) {
(Not, Bool(b)) => Bool(!b),
(Not, I8(n)) => I8(!n),
(Neg, I8(n)) => I8(-n),
(Not, I16(n)) => I16(!n),
(Neg, I16(n)) => I16(-n),
(Not, I32(n)) => I32(!n),
(Neg, I32(n)) => I32(-n),
(Not, I64(n)) => I64(!n),
(Neg, I64(n)) => I64(-n),
(Not, U8(n)) => U8(!n),
(Not, U16(n)) => U16(!n),
(Not, U32(n)) => U32(!n),
(Not, U64(n)) => U64(!n),
_ => unimplemented!(),
}
}