An optimization attempt

compiler-errors · compiler-errors · commit 93b52c8bf296 · 2025-01-25T16:05:04.000Z
diff --git a/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs
@@ -1,3 +1,4 @@
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_hir::def_id::DefId;
 use rustc_infer::infer::canonical::QueryRegionConstraints;
 use rustc_infer::infer::outlives::obligations::{TypeOutlives, TypeOutlivesDelegate};
@@ -36,7 +37,7 @@ pub(crate) struct ConstraintConversion<'a, 'tcx> {
     /// our special inference variable there, we would mess that up.
     implicit_region_bound: ty::Region<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
-    known_type_outlives: &'a [ty::PolyTypeOutlivesPredicate<'tcx>],
+    known_type_outlives: &'a FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>>,
     locations: Locations,
     span: Span,
     category: ConstraintCategory<'tcx>,
@@ -50,7 +51,7 @@ impl<'a, 'tcx> ConstraintConversion<'a, 'tcx> {
         universal_regions: &'a UniversalRegions<'tcx>,
         implicit_region_bound: ty::Region<'tcx>,
         param_env: ty::ParamEnv<'tcx>,
-        known_type_outlives: &'a [ty::PolyTypeOutlivesPredicate<'tcx>],
+        known_type_outlives: &'a FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>>,
         locations: Locations,
         span: Span,
         category: ConstraintCategory<'tcx>,
diff --git a/compiler/rustc_borrowck/src/type_check/free_region_relations.rs b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs
@@ -1,4 +1,5 @@
 use rustc_data_structures::frozen::Frozen;
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_data_structures::transitive_relation::{TransitiveRelation, TransitiveRelationBuilder};
 use rustc_hir::def::DefKind;
 use rustc_infer::infer::canonical::QueryRegionConstraints;
@@ -42,7 +43,7 @@ type NormalizedInputsAndOutput<'tcx> = Vec<Ty<'tcx>>;
 
 pub(crate) struct CreateResult<'tcx> {
     pub(crate) universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>,
-    pub(crate) known_type_outlives: Vec<ty::PolyTypeOutlivesPredicate<'tcx>>,
+    pub(crate) known_type_outlives: FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>>,
     pub(crate) normalized_inputs_and_output: NormalizedInputsAndOutput<'tcx>,
 }
 
@@ -59,7 +60,7 @@ pub(crate) fn create<'tcx>(
         implicit_region_bound,
         constraints,
         universal_regions,
-        known_type_outlives: vec![],
+        known_type_outlives: FxIndexSet::default(),
         outlives: Default::default(),
         inverse_outlives: Default::default(),
     }
@@ -186,7 +187,7 @@ struct UniversalRegionRelationsBuilder<'a, 'tcx> {
 
     // outputs:
     outlives: TransitiveRelationBuilder<RegionVid>,
-    known_type_outlives: Vec<ty::PolyTypeOutlivesPredicate<'tcx>>,
+    known_type_outlives: FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>>,
     inverse_outlives: TransitiveRelationBuilder<RegionVid>,
 }
 
@@ -370,7 +371,7 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> {
             }
         }
 
-        self.known_type_outlives.push(outlives);
+        self.known_type_outlives.insert(outlives);
     }
 
     /// Update the type of a single local, which should represent
@@ -416,14 +417,14 @@ impl<'tcx> UniversalRegionRelationsBuilder<'_, 'tcx> {
                 }
 
                 OutlivesBound::RegionSubParam(r_a, param_b) => {
-                    self.known_type_outlives.push(ty::Binder::dummy(ty::OutlivesPredicate(
+                    self.known_type_outlives.insert(ty::Binder::dummy(ty::OutlivesPredicate(
                         Ty::new_param(self.infcx.tcx, param_b.index, param_b.name),
                         r_a,
                     )));
                 }
 
                 OutlivesBound::RegionSubAlias(r_a, alias_b) => {
-                    self.known_type_outlives.push(ty::Binder::dummy(ty::OutlivesPredicate(
+                    self.known_type_outlives.insert(ty::Binder::dummy(ty::OutlivesPredicate(
                         Ty::new_alias(self.infcx.tcx, alias_b.kind(self.infcx.tcx), alias_b),
                         r_a,
                     )));
diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -552,7 +552,7 @@ 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>,
-    known_type_outlives: Vec<ty::PolyTypeOutlivesPredicate<'tcx>>,
+    known_type_outlives: FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>>,
     implicit_region_bound: ty::Region<'tcx>,
     reported_errors: FxIndexSet<(Ty<'tcx>, Span)>,
     universal_regions: &'a UniversalRegions<'tcx>,
diff --git a/compiler/rustc_infer/src/infer/outlives/env.rs b/compiler/rustc_infer/src/infer/outlives/env.rs
@@ -1,3 +1,4 @@
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_data_structures::transitive_relation::TransitiveRelationBuilder;
 use rustc_middle::{bug, ty};
 
@@ -25,7 +26,7 @@ use crate::infer::free_regions::FreeRegionMap;
 pub struct OutlivesEnvironment<'tcx> {
     pub param_env: ty::ParamEnv<'tcx>,
     free_region_map: FreeRegionMap<'tcx>,
-    known_type_outlives: Vec<ty::PolyTypeOutlivesPredicate<'tcx>>,
+    known_type_outlives: FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>>,
 }
 
 impl<'tcx> OutlivesEnvironment<'tcx> {
@@ -36,7 +37,7 @@ impl<'tcx> OutlivesEnvironment<'tcx> {
             Item = ty::Binder<'tcx, ty::OutlivesPredicate<'tcx, ty::GenericArg<'tcx>>>,
         >,
     ) -> Self {
-        let mut known_type_outlives = vec![];
+        let mut known_type_outlives = FxIndexSet::default();
         let mut region_relation = TransitiveRelationBuilder::default();
 
         // Record relationships such as `T:'x` that don't go into the
@@ -67,7 +68,7 @@ impl<'tcx> OutlivesEnvironment<'tcx> {
                     }
                 }
                 ty::GenericArgKind::Type(ty_b) => {
-                    known_type_outlives.push(bound.rebind(ty::OutlivesPredicate(ty_b, r_a)));
+                    known_type_outlives.insert(bound.rebind(ty::OutlivesPredicate(ty_b, r_a)));
                 }
                 ty::GenericArgKind::Const(_) => unreachable!(),
             }
@@ -86,7 +87,7 @@ impl<'tcx> OutlivesEnvironment<'tcx> {
     }
 
     /// Borrows current `known_type_outlives`.
-    pub fn known_type_outlives(&self) -> &[ty::PolyTypeOutlivesPredicate<'tcx>] {
+    pub fn known_type_outlives(&self) -> &FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>> {
         &self.known_type_outlives
     }
 }
diff --git a/compiler/rustc_infer/src/infer/outlives/obligations.rs b/compiler/rustc_infer/src/infer/outlives/obligations.rs
@@ -59,6 +59,7 @@
 //! might later infer `?U` to something like `&'b u32`, which would
 //! imply that `'b: 'a`.
 
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_data_structures::undo_log::UndoLogs;
 use rustc_middle::bug;
 use rustc_middle::mir::ConstraintCategory;
@@ -226,7 +227,7 @@ where
         delegate: D,
         tcx: TyCtxt<'tcx>,
         implicit_region_bound: Option<ty::Region<'tcx>>,
-        known_type_outlives: &'cx [ty::PolyTypeOutlivesPredicate<'tcx>],
+        known_type_outlives: &'cx FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>>,
     ) -> Self {
         Self {
             delegate,
diff --git a/compiler/rustc_infer/src/infer/outlives/test_type_match.rs b/compiler/rustc_infer/src/infer/outlives/test_type_match.rs
@@ -3,6 +3,7 @@ use std::collections::hash_map::Entry;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::ty::error::TypeError;
 use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitableExt};
+use rustc_type_ir::fast_reject::{self, TreatParams};
 use tracing::instrument;
 
 use crate::infer::region_constraints::VerifyIfEq;
@@ -81,8 +82,12 @@ pub(super) fn can_match_erased_ty<'tcx>(
     if outlives_ty == erased_ty {
         // pointless micro-optimization
         true
-    } else {
+    } else if fast_reject::simplify_type(tcx, erased_ty, TreatParams::AsRigid)
+        == fast_reject::simplify_type(tcx, outlives_ty, TreatParams::AsRigid)
+    {
         MatchAgainstHigherRankedOutlives::new(tcx).relate(outlives_ty, erased_ty).is_ok()
+    } else {
+        false
     }
 }
 
diff --git a/compiler/rustc_infer/src/infer/outlives/verify.rs b/compiler/rustc_infer/src/infer/outlives/verify.rs
@@ -1,5 +1,6 @@
 use std::assert_matches::assert_matches;
 
+use rustc_data_structures::fx::FxIndexSet;
 use rustc_middle::ty::{self, OutlivesPredicate, Ty, TyCtxt};
 use rustc_type_ir::outlives::{Component, compute_alias_components_recursive};
 use smallvec::smallvec;
@@ -22,14 +23,14 @@ pub(crate) struct VerifyBoundCx<'cx, 'tcx> {
     /// Outside of borrowck the only way to prove `T: '?0` is by
     /// setting  `'?0` to `'empty`.
     implicit_region_bound: Option<ty::Region<'tcx>>,
-    known_type_outlives: &'cx [ty::PolyTypeOutlivesPredicate<'tcx>],
+    known_type_outlives: &'cx FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>>,
 }
 
 impl<'cx, 'tcx> VerifyBoundCx<'cx, 'tcx> {
     pub(crate) fn new(
         tcx: TyCtxt<'tcx>,
         implicit_region_bound: Option<ty::Region<'tcx>>,
-        known_type_outlives: &'cx [ty::PolyTypeOutlivesPredicate<'tcx>],
+        known_type_outlives: &'cx FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>>,
     ) -> Self {
         Self { tcx, implicit_region_bound, known_type_outlives }
     }

Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,4 @@`
	`1`	`+use rustc_data_structures::fx::FxIndexSet;`
`1`	`2`	`use rustc_data_structures::transitive_relation::TransitiveRelationBuilder;`
`2`	`3`	`use rustc_middle::{bug, ty};`
`3`	`4`
`@@ -25,7 +26,7 @@ use crate::infer::free_regions::FreeRegionMap;`
`25`	`26`	`pub struct OutlivesEnvironment<'tcx> {`
`26`	`27`	`pub param_env: ty::ParamEnv<'tcx>,`
`27`	`28`	`free_region_map: FreeRegionMap<'tcx>,`
`28`		`- known_type_outlives: Vec<ty::PolyTypeOutlivesPredicate<'tcx>>,`
	`29`	`+ known_type_outlives: FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>>,`
`29`	`30`	`}`
`30`	`31`
`31`	`32`	`impl<'tcx> OutlivesEnvironment<'tcx> {`
`@@ -36,7 +37,7 @@ impl<'tcx> OutlivesEnvironment<'tcx> {`
`36`	`37`	`Item = ty::Binder<'tcx, ty::OutlivesPredicate<'tcx, ty::GenericArg<'tcx>>>,`
`37`	`38`	`>,`
`38`	`39`	`) -> Self {`
`39`		`- let mut known_type_outlives = vec![];`
	`40`	`+ let mut known_type_outlives = FxIndexSet::default();`
`40`	`41`	`let mut region_relation = TransitiveRelationBuilder::default();`
`41`	`42`
`42`	`43`	// Record relationships such as `T:'x` that don't go into the
`@@ -67,7 +68,7 @@ impl<'tcx> OutlivesEnvironment<'tcx> {`
`67`	`68`	`}`
`68`	`69`	`}`
`69`	`70`	`ty::GenericArgKind::Type(ty_b) => {`
`70`		`- known_type_outlives.push(bound.rebind(ty::OutlivesPredicate(ty_b, r_a)));`
	`71`	`+ known_type_outlives.insert(bound.rebind(ty::OutlivesPredicate(ty_b, r_a)));`
`71`	`72`	`}`
`72`	`73`	`ty::GenericArgKind::Const(_) => unreachable!(),`
`73`	`74`	`}`
`@@ -86,7 +87,7 @@ impl<'tcx> OutlivesEnvironment<'tcx> {`
`86`	`87`	`}`
`87`	`88`
`88`	`89`	/// Borrows current `known_type_outlives`.
`89`		`- pub fn known_type_outlives(&self) -> &[ty::PolyTypeOutlivesPredicate<'tcx>] {`
	`90`	`+ pub fn known_type_outlives(&self) -> &FxIndexSet<ty::PolyTypeOutlivesPredicate<'tcx>> {`
`90`	`91`	`&self.known_type_outlives`
`91`	`92`	`}`
`92`	`93`	`}`