Mirrors/rust-clippy
2
0
Fork 0
mirror of https://github.com/rust-lang/rust-clippy synced 2024-11-13 08:27:14 +00:00
Code Issues Projects Releases Packages Wiki Activity

Merge pull request #205 from Manishearth/const

Browse source 
Mul and Div for integers
This commit is contained in:
llogiq 2015-08-19 13:24:59 +02:00
commit 85f7f4c9b4
2 changed files with 29 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

28
src/consts.rs
View file

@ -320,7 +320,7 @@ impl<'c, 'cc> ConstEvalContext<'c, 'cc> {
/// create `Some(Vec![..])` of all constants, unless there is any
/// non-constant part
fn multi<E: Deref<Target=Expr> + Sized>(&mut self, vec: &[E]) ->
fn multi<E: Deref<Target=Expr> + Sized>(&mut self, vec: &[E]) ->
Option<Vec<Constant>> {
vec.iter().map(|elem| self.expr(elem))
.collect::<Option<_>>()
@ -388,9 +388,8 @@ impl<'c, 'cc> ConstEvalContext<'c, 'cc> {
match (l, r) {
(ConstantByte(l8), ConstantByte(r8)) => if r8 > l8 {
None } else { Some(ConstantByte(l8 - r8)) },
(ConstantInt(l64, lty), ConstantInt(r64, rty)) => {
let (ln, rn) = (is_negative(lty), is_negative(rty));
match (ln, rn) {
(ConstantInt(l64, lty), ConstantInt(r64, rty)) =>
match (is_negative(lty), is_negative(rty)) {
(false, false) => sub_int(l64, lty, r64, rty, r64 > l64),
(true, true) => sub_int(l64, lty, r64, rty, l64 > r64),
(true, false) => unify_int_type(lty, rty, Minus)
@ -399,12 +398,11 @@ impl<'c, 'cc> ConstEvalContext<'c, 'cc> {
(false, true) => unify_int_type(lty, rty, Plus)
.and_then(|ty| l64.checked_add(r64).map(
|v| ConstantInt(v, ty))),
}
},
},
_ => None,
}),
//BiMul,
//BiDiv,
BiMul => self.divmul(left, right, u64::checked_mul),
BiDiv => self.divmul(left, right, u64::checked_div),
//BiRem,
BiAnd => self.short_circuit(left, right, false),
BiOr => self.short_circuit(left, right, true),
@ -425,6 +423,20 @@ impl<'c, 'cc> ConstEvalContext<'c, 'cc> {
}
}
fn divmul<F>(&mut self, left: &Expr, right: &Expr, f: F)
-> Option<Constant> where F: Fn(u64, u64) -> Option<u64> {
self.binop_apply(left, right, |l, r|
match (l, r) {
(ConstantInt(l64, lty), ConstantInt(r64, rty)) => {
f(l64, r64).and_then(|value|
unify_int_type(lty, rty, if is_negative(lty) ==
is_negative(rty) { Plus } else { Minus })
.map(|ty| ConstantInt(value, ty)))
},
_ => None,
})
}
fn bitop<F>(&mut self, left: &Expr, right: &Expr, f: F)
-> Option<Constant> where F: Fn(u64, u64) -> u64 {
self.binop_apply(left, right, |l, r| match (l, r) {

9
tests/consts.rs
View file

@ -40,6 +40,8 @@ fn check(expect: Constant, expr: &Expr) {
const TRUE : Constant = ConstantBool(true);
const FALSE : Constant = ConstantBool(false);
const ZERO : Constant = ConstantInt(0, UnsuffixedIntLit(Plus));
const ONE : Constant = ConstantInt(1, UnsuffixedIntLit(Plus));
const TWO : Constant = ConstantInt(2, UnsuffixedIntLit(Plus));
#[test]
fn test_lit() {
@ -56,10 +58,17 @@ fn test_ops() {
check(FALSE, &binop(BiAnd, lit(LitBool(false)), lit(LitBool(true))));
let litzero = lit(LitInt(0, UnsuffixedIntLit(Plus)));
let litone = lit(LitInt(1, UnsuffixedIntLit(Plus)));
check(TRUE, &binop(BiEq, litzero.clone(), litzero.clone()));
check(TRUE, &binop(BiGe, litzero.clone(), litzero.clone()));
check(TRUE, &binop(BiLe, litzero.clone(), litzero.clone()));
check(FALSE, &binop(BiNe, litzero.clone(), litzero.clone()));
check(FALSE, &binop(BiGt, litzero.clone(), litzero.clone()));
check(FALSE, &binop(BiLt, litzero.clone(), litzero.clone()));
check(ZERO, &binop(BiAdd, litzero.clone(), litzero.clone()));
check(TWO, &binop(BiAdd, litone.clone(), litone.clone()));
check(ONE, &binop(BiSub, litone.clone(), litzero.clone()));
check(ONE, &binop(BiMul, litone.clone(), litone.clone()));
check(ONE, &binop(BiDiv, litone.clone(), litone.clone()));
}