mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-25 16:24:46 +00:00
Simplify path compression logic
This commit is contained in:
parent
d2a01760bc
commit
905db03b28
@ -62,15 +62,22 @@ impl scc::Annotation for RegionTracker {
|
||||
|
||||
impl RegionTracker {
|
||||
pub fn new(rvid: RegionVid, definition: &RegionDefinition<'_>) -> Self {
|
||||
let (representative_is_placeholder, representative_is_existential) = match definition.origin {
|
||||
rustc_infer::infer::NllRegionVariableOrigin::FreeRegion => (false, false),
|
||||
rustc_infer::infer::NllRegionVariableOrigin::Placeholder(_) => (true, false),
|
||||
rustc_infer::infer::NllRegionVariableOrigin::Existential { .. } => (false, true),
|
||||
};
|
||||
|
||||
let placeholder_universe =
|
||||
if definition.is_placeholder() { definition.universe } else { UniverseIndex::ROOT };
|
||||
if representative_is_placeholder { definition.universe } else { UniverseIndex::ROOT };
|
||||
|
||||
|
||||
Self {
|
||||
max_placeholder_universe_reached: placeholder_universe,
|
||||
min_reachable_universe: definition.universe,
|
||||
representative: rvid,
|
||||
representative_is_placeholder: definition.is_placeholder(),
|
||||
representative_is_existential: definition.is_existential(),
|
||||
representative_is_placeholder,
|
||||
representative_is_existential,
|
||||
}
|
||||
}
|
||||
pub fn universe(self) -> UniverseIndex {
|
||||
|
@ -2163,10 +2163,12 @@ impl<'tcx> RegionDefinition<'tcx> {
|
||||
Self { origin, universe, external_name: None }
|
||||
}
|
||||
|
||||
#[inline(always)]
|
||||
pub fn is_placeholder(&self) -> bool {
|
||||
matches!(self.origin, NllRegionVariableOrigin::Placeholder(_))
|
||||
}
|
||||
|
||||
#[inline(always)]
|
||||
pub fn is_existential(&self) -> bool {
|
||||
matches!(self.origin, NllRegionVariableOrigin::Existential { .. })
|
||||
}
|
||||
|
@ -393,38 +393,23 @@ where
|
||||
// `InCycleWith` upwards.
|
||||
// This loop performs the downward link encoding mentioned above. Details below!
|
||||
let node_state = {
|
||||
let mut annotation = (self.to_annotation)(node);
|
||||
|
||||
loop {
|
||||
debug!("find_state(r = {node:?} in state {:?})", self.node_states[node]);
|
||||
match self.node_states[node] {
|
||||
NodeState::NotVisited => break NodeState::NotVisited,
|
||||
NodeState::BeingVisited { depth, annotation: previous_annotation } => {
|
||||
break NodeState::BeingVisited {
|
||||
depth,
|
||||
annotation: previous_annotation.merge_scc(annotation),
|
||||
};
|
||||
}
|
||||
s @ (NodeState::NotVisited | NodeState::BeingVisited{..} | NodeState::InCycle { .. }) => break s,
|
||||
NodeState::InCycleWith { parent } => {
|
||||
// We test this, to be extremely sure that we never
|
||||
// ever break our termination condition for the
|
||||
// reverse iteration loop.
|
||||
assert!(node != parent, "Node can not be in cycle with itself");
|
||||
|
||||
annotation = annotation.merge_scc((self.to_annotation)(node));
|
||||
|
||||
// Store the previous node as an inverted list link
|
||||
self.node_states[node] = NodeState::InCycleWith { parent: previous_node };
|
||||
// Update to parent node.
|
||||
previous_node = node;
|
||||
node = parent;
|
||||
}
|
||||
NodeState::InCycle { scc_index, annotation: previous_annotation } => {
|
||||
break NodeState::InCycle {
|
||||
scc_index,
|
||||
annotation: previous_annotation.merge_scc(annotation),
|
||||
};
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
};
|
||||
|
Loading…
Reference in New Issue
Block a user