diff options
Diffstat (limited to 'compiler')
6 files changed, 30 insertions, 20 deletions
diff --git a/compiler/rustc_trait_selection/src/solve/delegate.rs b/compiler/rustc_trait_selection/src/solve/delegate.rs index 17429e15cce..7426504e139 100644 --- a/compiler/rustc_trait_selection/src/solve/delegate.rs +++ b/compiler/rustc_trait_selection/src/solve/delegate.rs @@ -12,11 +12,11 @@ use rustc_infer::traits::solve::Goal; use rustc_middle::traits::query::NoSolution; use rustc_middle::traits::solve::Certainty; use rustc_middle::ty::{ - self, SizedTraitKind, Ty, TyCtxt, TypeFlags, TypeFoldable, TypeVisitableExt as _, TypingMode, + self, Ty, TyCtxt, TypeFlags, TypeFoldable, TypeVisitableExt as _, TypingMode, }; use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span}; -use crate::traits::{EvaluateConstErr, ObligationCause, specialization_graph}; +use crate::traits::{EvaluateConstErr, ObligationCause, sizedness_fast_path, specialization_graph}; #[repr(transparent)] pub struct SolverDelegate<'tcx>(InferCtxt<'tcx>); @@ -76,19 +76,11 @@ impl<'tcx> rustc_next_trait_solver::delegate::SolverDelegate for SolverDelegate< if trait_pred.polarity() == ty::PredicatePolarity::Positive { match self.0.tcx.as_lang_item(trait_pred.def_id()) { - Some(LangItem::Sized) - if self - .resolve_vars_if_possible(trait_pred.self_ty().skip_binder()) - .has_trivial_sizedness(self.0.tcx, SizedTraitKind::Sized) => - { - return Some(Certainty::Yes); - } - Some(LangItem::MetaSized) - if self - .resolve_vars_if_possible(trait_pred.self_ty().skip_binder()) - .has_trivial_sizedness(self.0.tcx, SizedTraitKind::MetaSized) => - { - return Some(Certainty::Yes); + Some(LangItem::Sized) | Some(LangItem::MetaSized) => { + let predicate = self.resolve_vars_if_possible(goal.predicate); + if sizedness_fast_path(self.tcx, predicate, goal.param_env) { + return Some(Certainty::Yes); + } } Some(LangItem::Copy | LangItem::Clone) => { let self_ty = diff --git a/compiler/rustc_trait_selection/src/traits/fulfill.rs b/compiler/rustc_trait_selection/src/traits/fulfill.rs index e35f89358e9..6b884b36080 100644 --- a/compiler/rustc_trait_selection/src/traits/fulfill.rs +++ b/compiler/rustc_trait_selection/src/traits/fulfill.rs @@ -363,7 +363,7 @@ impl<'a, 'tcx> ObligationProcessor for FulfillProcessor<'a, 'tcx> { let infcx = self.selcx.infcx; - if sizedness_fast_path(infcx.tcx, obligation.predicate) { + if sizedness_fast_path(infcx.tcx, obligation.predicate, obligation.param_env) { return ProcessResult::Changed(thin_vec![]); } diff --git a/compiler/rustc_trait_selection/src/traits/query/type_op/prove_predicate.rs b/compiler/rustc_trait_selection/src/traits/query/type_op/prove_predicate.rs index 22eeb285b37..f24214145ba 100644 --- a/compiler/rustc_trait_selection/src/traits/query/type_op/prove_predicate.rs +++ b/compiler/rustc_trait_selection/src/traits/query/type_op/prove_predicate.rs @@ -15,7 +15,7 @@ impl<'tcx> super::QueryTypeOp<'tcx> for ProvePredicate<'tcx> { tcx: TyCtxt<'tcx>, key: &ParamEnvAnd<'tcx, Self>, ) -> Option<Self::QueryResponse> { - if sizedness_fast_path(tcx, key.value.predicate) { + if sizedness_fast_path(tcx, key.value.predicate, key.param_env) { return Some(()); } diff --git a/compiler/rustc_trait_selection/src/traits/select/mod.rs b/compiler/rustc_trait_selection/src/traits/select/mod.rs index 2b563c5b8d5..f90316f520b 100644 --- a/compiler/rustc_trait_selection/src/traits/select/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/select/mod.rs @@ -597,7 +597,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { None => self.check_recursion_limit(&obligation, &obligation)?, } - if sizedness_fast_path(self.tcx(), obligation.predicate) { + if sizedness_fast_path(self.tcx(), obligation.predicate, obligation.param_env) { return Ok(EvaluatedToOk); } diff --git a/compiler/rustc_trait_selection/src/traits/util.rs b/compiler/rustc_trait_selection/src/traits/util.rs index 0c14b124e25..c3d60ec45c4 100644 --- a/compiler/rustc_trait_selection/src/traits/util.rs +++ b/compiler/rustc_trait_selection/src/traits/util.rs @@ -365,7 +365,11 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for PlaceholderReplacer<'_, 'tcx> { } } -pub fn sizedness_fast_path<'tcx>(tcx: TyCtxt<'tcx>, predicate: ty::Predicate<'tcx>) -> bool { +pub fn sizedness_fast_path<'tcx>( + tcx: TyCtxt<'tcx>, + predicate: ty::Predicate<'tcx>, + param_env: ty::ParamEnv<'tcx>, +) -> bool { // Proving `Sized`/`MetaSized`, very often on "obviously sized" types like // `&T`, accounts for about 60% percentage of the predicates we have to prove. No need to // canonicalize and all that for such cases. @@ -390,6 +394,20 @@ pub fn sizedness_fast_path<'tcx>(tcx: TyCtxt<'tcx>, predicate: ty::Predicate<'tc debug!("fast path -- trivial sizedness"); return true; } + + if matches!(trait_pred.self_ty().kind(), ty::Param(_) | ty::Placeholder(_)) { + for clause in param_env.caller_bounds() { + if let ty::ClauseKind::Trait(clause_pred) = clause.kind().skip_binder() + && clause_pred.polarity == ty::PredicatePolarity::Positive + && clause_pred.self_ty() == trait_pred.self_ty() + && (clause_pred.def_id() == trait_pred.def_id() + || (sizedness == SizedTraitKind::MetaSized + && tcx.is_lang_item(clause_pred.def_id(), LangItem::Sized))) + { + return true; + } + } + } } false diff --git a/compiler/rustc_traits/src/evaluate_obligation.rs b/compiler/rustc_traits/src/evaluate_obligation.rs index 7771db855d7..819b8e3231c 100644 --- a/compiler/rustc_traits/src/evaluate_obligation.rs +++ b/compiler/rustc_traits/src/evaluate_obligation.rs @@ -24,7 +24,7 @@ fn evaluate_obligation<'tcx>( debug!("evaluate_obligation: goal={:#?}", goal); let ParamEnvAnd { param_env, value: predicate } = goal; - if sizedness_fast_path(tcx, predicate) { + if sizedness_fast_path(tcx, predicate, param_env) { return Ok(EvaluationResult::EvaluatedToOk); } |