From 2c8bbeebf1c630d06e44fa131d1cb0908b5ad56c Mon Sep 17 00:00:00 2001 From: Michael Goulet Date: Thu, 11 Jul 2024 19:15:00 -0400 Subject: [PATCH] Remove fully_normalize --- .../src/opaque_hidden_inferred_bound.rs | 27 +++++------ .../rustc_trait_selection/src/traits/mod.rs | 46 ++++--------------- .../src/traits/normalize.rs | 8 ++-- .../src/traits/specialize/mod.rs | 29 +++++------- 4 files changed, 36 insertions(+), 74 deletions(-) diff --git a/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs b/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs index 5ee73dbfdc658..fdb71ad41a754 100644 --- a/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs +++ b/compiler/rustc_lint/src/opaque_hidden_inferred_bound.rs @@ -5,8 +5,7 @@ use rustc_middle::ty::print::{PrintTraitPredicateExt as _, TraitPredPrintModifie use rustc_middle::ty::{self, fold::BottomUpFolder, Ty, TypeFoldable}; use rustc_session::{declare_lint, declare_lint_pass}; use rustc_span::{symbol::kw, Span}; -use rustc_trait_selection::traits; -use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt; +use rustc_trait_selection::traits::{self, ObligationCtxt}; use crate::{LateContext, LateLintPass, LintContext}; @@ -130,24 +129,26 @@ impl<'tcx> LateLintPass<'tcx> for OpaqueHiddenInferredBound { .iter_instantiated_copied(cx.tcx, proj.projection_term.args) { let assoc_pred = assoc_pred.fold_with(proj_replacer); - let Ok(assoc_pred) = traits::fully_normalize( - infcx, + + let ocx = ObligationCtxt::new(infcx); + let assoc_pred = + ocx.normalize(&traits::ObligationCause::dummy(), cx.param_env, assoc_pred); + if !ocx.select_all_or_error().is_empty() { + // Can't normalize for some reason...? + continue; + } + + ocx.register_obligation(traits::Obligation::new( + cx.tcx, traits::ObligationCause::dummy(), cx.param_env, assoc_pred, - ) else { - continue; - }; + )); // If that predicate doesn't hold modulo regions (but passed during type-check), // then we must've taken advantage of the hack in `project_and_unify_types` where // we replace opaques with inference vars. Emit a warning! - if !infcx.predicate_must_hold_modulo_regions(&traits::Obligation::new( - cx.tcx, - traits::ObligationCause::dummy(), - cx.param_env, - assoc_pred, - )) { + if !ocx.select_all_or_error().is_empty() { // If it's a trait bound and an opaque that doesn't satisfy it, // then we can emit a suggestion to add the bound. let add_bound = match (proj_term.kind(), assoc_pred.kind().skip_binder()) { diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs index 703ff2f7f1698..d28982ed84925 100644 --- a/compiler/rustc_trait_selection/src/traits/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/mod.rs @@ -271,13 +271,14 @@ fn do_normalize_predicates<'tcx>( // them here too, and we will remove this function when // we move over to lazy normalization *anyway*. let infcx = tcx.infer_ctxt().ignoring_regions().build(); - let predicates = match fully_normalize(&infcx, cause, elaborated_env, predicates) { - Ok(predicates) => predicates, - Err(errors) => { - let reported = infcx.err_ctxt().report_fulfillment_errors(errors); - return Err(reported); - } - }; + let ocx = ObligationCtxt::new_with_diagnostics(&infcx); + let predicates = ocx.normalize(&cause, elaborated_env, predicates); + + let errors = ocx.select_all_or_error(); + if !errors.is_empty() { + let reported = infcx.err_ctxt().report_fulfillment_errors(errors); + return Err(reported); + } debug!("do_normalize_predicates: normalized predicates = {:?}", predicates); @@ -465,37 +466,6 @@ pub fn normalize_param_env_or_error<'tcx>( ty::ParamEnv::new(tcx.mk_clauses(&predicates), unnormalized_env.reveal()) } -/// Normalize a type and process all resulting obligations, returning any errors. -/// -/// FIXME(-Znext-solver): This should be replaced by `At::deeply_normalize` -/// which has the same behavior with the new solver. Because using a separate -/// fulfillment context worsens caching in the old solver, `At::deeply_normalize` -/// is still lazy with the old solver as it otherwise negatively impacts perf. -#[instrument(skip_all)] -pub fn fully_normalize<'tcx, T>( - infcx: &InferCtxt<'tcx>, - cause: ObligationCause<'tcx>, - param_env: ty::ParamEnv<'tcx>, - value: T, -) -> Result>> -where - T: TypeFoldable>, -{ - let ocx = ObligationCtxt::new_with_diagnostics(infcx); - debug!(?value); - let normalized_value = ocx.normalize(&cause, param_env, value); - debug!(?normalized_value); - debug!("select_all_or_error start"); - let errors = ocx.select_all_or_error(); - if !errors.is_empty() { - return Err(errors); - } - debug!("select_all_or_error complete"); - let resolved_value = infcx.resolve_vars_if_possible(normalized_value); - debug!(?resolved_value); - Ok(resolved_value) -} - /// Normalizes the predicates and checks whether they hold in an empty environment. If this /// returns true, then either normalize encountered an error or one of the predicates did not /// hold. Used when creating vtables to check for unsatisfiable methods. diff --git a/compiler/rustc_trait_selection/src/traits/normalize.rs b/compiler/rustc_trait_selection/src/traits/normalize.rs index 3a7481acbafd3..01ba8c02ea6eb 100644 --- a/compiler/rustc_trait_selection/src/traits/normalize.rs +++ b/compiler/rustc_trait_selection/src/traits/normalize.rs @@ -42,11 +42,9 @@ impl<'tcx> At<'_, 'tcx> { /// same goals in both a temporary and the shared context which negatively impacts /// performance as these don't share caching. /// - /// FIXME(-Znext-solver): This has the same behavior as `traits::fully_normalize` - /// in the new solver, but because of performance reasons, we currently reuse an - /// existing fulfillment context in the old solver. Once we also eagerly prove goals with - /// the old solver or have removed the old solver, remove `traits::fully_normalize` and - /// rename this function to `At::fully_normalize`. + /// FIXME(-Znext-solver): For performance reasons, we currently reuse an existing + /// fulfillment context in the old solver. Once we have removed the old solver, we + /// can remove the `fulfill_cx` parameter on this function. fn deeply_normalize( self, value: T, diff --git a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs index 6a904ef487eae..3c33d13567d78 100644 --- a/compiler/rustc_trait_selection/src/traits/specialize/mod.rs +++ b/compiler/rustc_trait_selection/src/traits/specialize/mod.rs @@ -18,9 +18,7 @@ use crate::error_reporting::traits::to_pretty_impl_header; use crate::errors::NegativePositiveConflict; use crate::infer::{InferCtxt, InferOk, TyCtxtInferExt}; use crate::traits::select::IntercrateAmbiguityCause; -use crate::traits::{ - self, coherence, FutureCompatOverlapErrorKind, ObligationCause, ObligationCtxt, -}; +use crate::traits::{coherence, FutureCompatOverlapErrorKind, ObligationCause, ObligationCtxt}; use rustc_data_structures::fx::FxIndexSet; use rustc_errors::{codes::*, Diag, EmissionGuarantee}; use rustc_hir::def_id::{DefId, LocalDefId}; @@ -219,19 +217,17 @@ fn fulfill_implication<'tcx>( param_env, source_trait_ref, target_impl ); - let source_trait_ref = - match traits::fully_normalize(infcx, ObligationCause::dummy(), param_env, source_trait_ref) - { - Ok(source_trait_ref) => source_trait_ref, - Err(_errors) => { - infcx.dcx().span_delayed_bug( - infcx.tcx.def_span(source_impl), - format!("failed to fully normalize {source_trait_ref}"), - ); - source_trait_ref - } - }; + let ocx = ObligationCtxt::new(infcx); + let source_trait_ref = ocx.normalize(&ObligationCause::dummy(), param_env, source_trait_ref); + if !ocx.select_all_or_error().is_empty() { + infcx.dcx().span_delayed_bug( + infcx.tcx.def_span(source_impl), + format!("failed to fully normalize {source_trait_ref}"), + ); + } + + let source_trait_ref = infcx.resolve_vars_if_possible(source_trait_ref); let source_trait = ImplSubject::Trait(source_trait_ref); let selcx = SelectionContext::new(infcx); @@ -253,9 +249,6 @@ fn fulfill_implication<'tcx>( return Err(()); }; - // Needs to be `in_snapshot` because this function is used to rebase - // generic parameters, which may happen inside of a select within a probe. - let ocx = ObligationCtxt::new(infcx); // attempt to prove all of the predicates for impl2 given those for impl1 // (which are packed up in penv) ocx.register_obligations(obligations.chain(more_obligations));