user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Rollup merge of #140604 - lcnr:revealing-use-prep, r=compiler-errors

Browse source 
yet another small borrowck cleanup

The last borrowck changes from #139587 which can be reviewed entirely separately.

r? `@compiler-errors`
This commit is contained in:
Matthias Krüger 2025-05-03 12:44:37 +02:00 • committed by GitHub
commit 4360fd7f34
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
3 changed files with 39 additions and 30 deletions
Download patch file Download diff file Expand all files Collapse all files

45
compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs
View file

@ -7,6 +7,8 @@ use rustc_middle::ty::RegionVid;
use crate::RegionInferenceContext;
use crate::constraints::ConstraintSccIndex;
use crate::region_infer::ConstraintSccs;
use crate::universal_regions::UniversalRegions;
pub(crate) struct ReverseSccGraph {
graph: VecGraph<ConstraintSccIndex>,
@ -19,6 +21,29 @@ pub(crate) struct ReverseSccGraph {
}
impl ReverseSccGraph {
pub(super) fn compute(
constraint_sccs: &ConstraintSccs,
universal_regions: &UniversalRegions<'_>,
) -> Self {
let graph = constraint_sccs.reverse();
let mut paired_scc_regions = universal_regions
.universal_regions_iter()
.map(|region| (constraint_sccs.scc(region), region))
.collect::<Vec<_>>();
paired_scc_regions.sort();
let universal_regions = paired_scc_regions.iter().map(|&(_, region)| region).collect();
let mut scc_regions = FxIndexMap::default();
let mut start = 0;
for chunk in paired_scc_regions.chunk_by(|&(scc1, _), &(scc2, _)| scc1 == scc2) {
let (scc, _) = chunk[0];
scc_regions.insert(scc, start..start + chunk.len());
start += chunk.len();
}
ReverseSccGraph { graph, scc_regions, universal_regions }
}
/// Find all universal regions that are required to outlive the given SCC.
pub(super) fn upper_bounds(&self, scc0: ConstraintSccIndex) -> impl Iterator<Item = RegionVid> {
let mut duplicates = FxIndexSet::default();
@ -40,23 +65,7 @@ impl RegionInferenceContext<'_> {
return;
}
let graph = self.constraint_sccs.reverse();
let mut paired_scc_regions = self
.universal_regions()
.universal_regions_iter()
.map(|region| (self.constraint_sccs.scc(region), region))
.collect::<Vec<_>>();
paired_scc_regions.sort();
let universal_regions = paired_scc_regions.iter().map(|&(_, region)| region).collect();
let mut scc_regions = FxIndexMap::default();
let mut start = 0;
for chunk in paired_scc_regions.chunk_by(|&(scc1, _), &(scc2, _)| scc1 == scc2) {
let (scc, _) = chunk[0];
scc_regions.insert(scc, start..start + chunk.len());
start += chunk.len();
}
self.rev_scc_graph = Some(ReverseSccGraph { graph, scc_regions, universal_regions });
self.rev_scc_graph =
Some(ReverseSccGraph::compute(&self.constraint_sccs, self.universal_regions()));
}
}

8
compiler/rustc_borrowck/src/type_check/free_region_relations.rs
View file

@ -41,8 +41,8 @@ type NormalizedInputsAndOutput<'tcx> = Vec<Ty<'tcx>>;
pub(crate) struct CreateResult<'tcx> {
pub(crate) universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>,
pub(crate) region_bound_pairs: RegionBoundPairs<'tcx>,
pub(crate) known_type_outlives_obligations: Vec<ty::PolyTypeOutlivesPredicate<'tcx>>,
pub(crate) region_bound_pairs: Frozen<RegionBoundPairs<'tcx>>,
pub(crate) known_type_outlives_obligations: Frozen<Vec<ty::PolyTypeOutlivesPredicate<'tcx>>>,
pub(crate) normalized_inputs_and_output: NormalizedInputsAndOutput<'tcx>,
}
@ -333,8 +333,8 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> {
outlives: self.outlives.freeze(),
inverse_outlives: self.inverse_outlives.freeze(),
}),
known_type_outlives_obligations,
region_bound_pairs: self.region_bound_pairs,
known_type_outlives_obligations: Frozen::freeze(known_type_outlives_obligations),
region_bound_pairs: Frozen::freeze(self.region_bound_pairs),
normalized_inputs_and_output,
}
}

16
compiler/rustc_borrowck/src/type_check/mod.rs
View file

@ -151,8 +151,8 @@ pub(crate) fn type_check<'a, 'tcx>(
body,
promoted,
user_type_annotations: &body.user_type_annotations,
region_bound_pairs,
known_type_outlives_obligations,
region_bound_pairs: &region_bound_pairs,
known_type_outlives_obligations: &known_type_outlives_obligations,
reported_errors: Default::default(),
universal_regions: &universal_region_relations.universal_regions,
location_table,
@ -216,8 +216,8 @@ struct TypeChecker<'a, 'tcx> {
/// User type annotations are shared between the main MIR and the MIR of
/// all of the promoted items.
user_type_annotations: &'a CanonicalUserTypeAnnotations<'tcx>,
region_bound_pairs: RegionBoundPairs<'tcx>,
known_type_outlives_obligations: Vec<ty::PolyTypeOutlivesPredicate<'tcx>>,
region_bound_pairs: &'a RegionBoundPairs<'tcx>,
known_type_outlives_obligations: &'a [ty::PolyTypeOutlivesPredicate<'tcx>],
reported_errors: FxIndexSet<(Ty<'tcx>, Span)>,
universal_regions: &'a UniversalRegions<'tcx>,
location_table: &'a PoloniusLocationTable,
@ -412,9 +412,9 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
constraint_conversion::ConstraintConversion::new(
self.infcx,
self.universal_regions,
&self.region_bound_pairs,
self.region_bound_pairs,
self.infcx.param_env,
&self.known_type_outlives_obligations,
self.known_type_outlives_obligations,
locations,
locations.span(self.body),
category,
@ -2506,9 +2506,9 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
constraint_conversion::ConstraintConversion::new(
self.infcx,
self.universal_regions,
&self.region_bound_pairs,
self.region_bound_pairs,
self.infcx.param_env,
&self.known_type_outlives_obligations,
self.known_type_outlives_obligations,
locations,
self.body.span, // irrelevant; will be overridden.
ConstraintCategory::Boring, // same as above.