1
Fork 0

don't store const var origins for known vars

This commit is contained in:
lcnr 2024-01-16 11:06:42 +01:00
parent f9c2421a2a
commit 290651be72
8 changed files with 70 additions and 165 deletions

View file

@ -120,7 +120,7 @@ pub enum ConstVariableOriginKind {
#[derive(Copy, Clone, Debug)]
pub enum ConstVariableValue<'tcx> {
Known { value: ty::Const<'tcx> },
Unknown { universe: ty::UniverseIndex },
Unknown { origin: ConstVariableOrigin, universe: ty::UniverseIndex },
}
impl<'tcx> ConstVariableValue<'tcx> {
@ -134,12 +134,6 @@ impl<'tcx> ConstVariableValue<'tcx> {
}
}
#[derive(Copy, Clone, Debug)]
pub struct ConstVarValue<'tcx> {
pub origin: ConstVariableOrigin,
pub val: ConstVariableValue<'tcx>,
}
#[derive(PartialEq, Copy, Clone, Debug)]
pub struct ConstVidKey<'tcx> {
pub vid: ty::ConstVid,
@ -153,7 +147,7 @@ impl<'tcx> From<ty::ConstVid> for ConstVidKey<'tcx> {
}
impl<'tcx> UnifyKey for ConstVidKey<'tcx> {
type Value = ConstVarValue<'tcx>;
type Value = ConstVariableValue<'tcx>;
#[inline]
fn index(&self) -> u32 {
self.vid.as_u32()
@ -167,23 +161,23 @@ impl<'tcx> UnifyKey for ConstVidKey<'tcx> {
}
}
impl<'tcx> UnifyValue for ConstVarValue<'tcx> {
impl<'tcx> UnifyValue for ConstVariableValue<'tcx> {
type Error = NoError;
fn unify_values(&value1: &Self, &value2: &Self) -> Result<Self, Self::Error> {
Ok(match (value1.val, value2.val) {
match (value1, value2) {
(ConstVariableValue::Known { .. }, ConstVariableValue::Known { .. }) => {
bug!("equating two const variables, both of which have known values")
}
// If one side is known, prefer that one.
(ConstVariableValue::Known { .. }, ConstVariableValue::Unknown { .. }) => value1,
(ConstVariableValue::Unknown { .. }, ConstVariableValue::Known { .. }) => value2,
(ConstVariableValue::Known { .. }, ConstVariableValue::Unknown { .. }) => Ok(value1),
(ConstVariableValue::Unknown { .. }, ConstVariableValue::Known { .. }) => Ok(value2),
// If both sides are *unknown*, it hardly matters, does it?
(
ConstVariableValue::Unknown { universe: universe1 },
ConstVariableValue::Unknown { universe: universe2 },
ConstVariableValue::Unknown { origin, universe: universe1 },
ConstVariableValue::Unknown { origin: _, universe: universe2 },
) => {
// If we unify two unbound variables, ?T and ?U, then whatever
// value they wind up taking (which must be the same value) must
@ -191,12 +185,9 @@ impl<'tcx> UnifyValue for ConstVarValue<'tcx> {
// universe is the minimum of the two universes, because that is
// the one which contains the fewest names in scope.
let universe = cmp::min(universe1, universe2);
ConstVarValue {
val: ConstVariableValue::Unknown { universe },
origin: value1.origin,
}
Ok(ConstVariableValue::Unknown { origin, universe })
}
})
}
}
}