From a621ec35aef00181be89c65a36bc44d061b99206 Mon Sep 17 00:00:00 2001 From: klensy Date: Mon, 24 Apr 2023 13:25:23 +0300 Subject: [PATCH] RegionInferenceContext: remove Rc from rev_scc_graph field --- compiler/rustc_borrowck/src/region_infer/mod.rs | 6 +++--- .../rustc_borrowck/src/region_infer/reverse_sccs.rs | 13 +++++-------- 2 files changed, 8 insertions(+), 11 deletions(-) diff --git a/compiler/rustc_borrowck/src/region_infer/mod.rs b/compiler/rustc_borrowck/src/region_infer/mod.rs index 65573c71f14..8fbe814c856 100644 --- a/compiler/rustc_borrowck/src/region_infer/mod.rs +++ b/compiler/rustc_borrowck/src/region_infer/mod.rs @@ -76,7 +76,7 @@ pub struct RegionInferenceContext<'tcx> { /// Reverse of the SCC constraint graph -- i.e., an edge `A -> B` exists if /// `B: A`. This is used to compute the universal regions that are required /// to outlive a given SCC. Computed lazily. - rev_scc_graph: Option>, + rev_scc_graph: Option, /// The "R0 member of [R1..Rn]" constraints, indexed by SCC. member_constraints: Rc>, @@ -813,9 +813,9 @@ impl<'tcx> RegionInferenceContext<'tcx> { // free region that must outlive the member region `R0` (`UB: // R0`). Therefore, we need only keep an option `O` if `UB: O` // for all UB. - let rev_scc_graph = self.reverse_scc_graph(); + self.compute_reverse_scc_graph(); let universal_region_relations = &self.universal_region_relations; - for ub in rev_scc_graph.upper_bounds(scc) { + for ub in self.rev_scc_graph.as_ref().unwrap().upper_bounds(scc) { debug!(?ub); choice_regions.retain(|&o_r| universal_region_relations.outlives(ub, o_r)); } diff --git a/compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs b/compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs index 23a59c12865..e5c6c4d8540 100644 --- a/compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs +++ b/compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs @@ -8,7 +8,6 @@ use rustc_data_structures::graph::vec_graph::VecGraph; use rustc_data_structures::graph::WithSuccessors; use rustc_middle::ty::RegionVid; use std::ops::Range; -use std::rc::Rc; pub(crate) struct ReverseSccGraph { graph: VecGraph, @@ -40,10 +39,10 @@ impl ReverseSccGraph { } impl RegionInferenceContext<'_> { - /// Compute and return the reverse SCC-based constraint graph (lazily). - pub(super) fn reverse_scc_graph(&mut self) -> Rc { - if let Some(g) = &self.rev_scc_graph { - return g.clone(); + /// Compute the reverse SCC-based constraint graph (lazily). + pub(super) fn compute_reverse_scc_graph(&mut self) { + if matches!(self.rev_scc_graph, Some(_)) { + return; } let graph = self.constraint_sccs.reverse(); @@ -63,8 +62,6 @@ impl RegionInferenceContext<'_> { start += group_size; } - let rev_graph = Rc::new(ReverseSccGraph { graph, scc_regions, universal_regions }); - self.rev_scc_graph = Some(rev_graph.clone()); - rev_graph + self.rev_scc_graph = Some(ReverseSccGraph { graph, scc_regions, universal_regions }); } }