diff options
Diffstat (limited to 'compiler/rustc_mir_build')
13 files changed, 162 insertions, 175 deletions
diff --git a/compiler/rustc_mir_build/src/build/expr/as_place.rs b/compiler/rustc_mir_build/src/build/expr/as_place.rs index e88f9dc1f08..6abf419dd49 100644 --- a/compiler/rustc_mir_build/src/build/expr/as_place.rs +++ b/compiler/rustc_mir_build/src/build/expr/as_place.rs @@ -7,6 +7,7 @@ use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_middle::hir::place::Projection as HirProjection; use rustc_middle::hir::place::ProjectionKind as HirProjectionKind; use rustc_middle::middle::region; +use rustc_middle::mir::tcx::PlaceTy; use rustc_middle::mir::AssertKind::BoundsCheck; use rustc_middle::mir::*; use rustc_middle::thir::*; @@ -71,7 +72,7 @@ pub(crate) enum PlaceBase { /// This is used internally when building a place for an expression like `a.b.c`. The fields `b` /// and `c` can be progressively pushed onto the place builder that is created when converting `a`. #[derive(Clone, Debug, PartialEq)] -pub(crate) struct PlaceBuilder<'tcx> { +pub(in crate::build) struct PlaceBuilder<'tcx> { base: PlaceBase, projection: Vec<PlaceElem<'tcx>>, } @@ -104,6 +105,8 @@ fn convert_to_hir_projections_and_truncate_for_capture<'tcx>( variant = Some(*idx); continue; } + // These do not affect anything, they just make sure we know the right type. + ProjectionElem::OpaqueCast(_) => continue, ProjectionElem::Index(..) | ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subslice { .. } => { @@ -201,10 +204,10 @@ fn find_capture_matching_projections<'a, 'tcx>( /// `PlaceBuilder` now starts from `PlaceBase::Local`. /// /// Returns a Result with the error being the PlaceBuilder (`from_builder`) that was not found. -fn to_upvars_resolved_place_builder<'a, 'tcx>( +#[instrument(level = "trace", skip(cx))] +fn to_upvars_resolved_place_builder<'tcx>( from_builder: PlaceBuilder<'tcx>, - tcx: TyCtxt<'tcx>, - typeck_results: &'a ty::TypeckResults<'tcx>, + cx: &Builder<'_, 'tcx>, ) -> Result<PlaceBuilder<'tcx>, PlaceBuilder<'tcx>> { match from_builder.base { PlaceBase::Local(_) => Ok(from_builder), @@ -219,13 +222,13 @@ fn to_upvars_resolved_place_builder<'a, 'tcx>( let Some((capture_index, capture)) = find_capture_matching_projections( - typeck_results, + cx.typeck_results, var_hir_id, closure_def_id, &from_builder.projection, ) else { - let closure_span = tcx.def_span(closure_def_id); - if !enable_precise_capture(tcx, closure_span) { + let closure_span = cx.tcx.def_span(closure_def_id); + if !enable_precise_capture(cx.tcx, closure_span) { bug!( "No associated capture found for {:?}[{:#?}] even though \ capture_disjoint_fields isn't enabled", @@ -242,8 +245,8 @@ fn to_upvars_resolved_place_builder<'a, 'tcx>( }; // We won't be building MIR if the closure wasn't local - let closure_hir_id = tcx.hir().local_def_id_to_hir_id(closure_def_id.expect_local()); - let closure_ty = typeck_results.node_type(closure_hir_id); + let closure_hir_id = cx.tcx.hir().local_def_id_to_hir_id(closure_def_id.expect_local()); + let closure_ty = cx.typeck_results.node_type(closure_hir_id); let substs = match closure_ty.kind() { ty::Closure(_, substs) => ty::UpvarSubsts::Closure(substs), @@ -270,12 +273,14 @@ fn to_upvars_resolved_place_builder<'a, 'tcx>( // We used some of the projections to build the capture itself, // now we apply the remaining to the upvar resolved place. + trace!(?capture.place, ?from_builder.projection); let remaining_projections = strip_prefix( capture.place.base_ty, from_builder.projection, &capture.place.projections, ); upvar_resolved_place_builder.projection.extend(remaining_projections); + trace!(?upvar_resolved_place_builder); Ok(upvar_resolved_place_builder) } @@ -294,16 +299,21 @@ fn strip_prefix<'tcx>( prefix_projections: &[HirProjection<'tcx>], ) -> impl Iterator<Item = PlaceElem<'tcx>> { let mut iter = projections.into_iter(); + let mut next = || match iter.next()? { + // Filter out opaque casts, they are unnecessary in the prefix. + ProjectionElem::OpaqueCast(..) => iter.next(), + other => Some(other), + }; for projection in prefix_projections { match projection.kind { HirProjectionKind::Deref => { - assert!(matches!(iter.next(), Some(ProjectionElem::Deref))); + assert!(matches!(next(), Some(ProjectionElem::Deref))); } HirProjectionKind::Field(..) => { if base_ty.is_enum() { - assert!(matches!(iter.next(), Some(ProjectionElem::Downcast(..)))); + assert!(matches!(next(), Some(ProjectionElem::Downcast(..)))); } - assert!(matches!(iter.next(), Some(ProjectionElem::Field(..)))); + assert!(matches!(next(), Some(ProjectionElem::Field(..)))); } HirProjectionKind::Index | HirProjectionKind::Subslice => { bug!("unexpected projection kind: {:?}", projection); @@ -315,24 +325,32 @@ fn strip_prefix<'tcx>( } impl<'tcx> PlaceBuilder<'tcx> { - pub(crate) fn into_place<'a>( - self, - tcx: TyCtxt<'tcx>, - typeck_results: &'a ty::TypeckResults<'tcx>, - ) -> Place<'tcx> { + pub(crate) fn into_place(self, cx: &Builder<'_, 'tcx>) -> Place<'tcx> { if let PlaceBase::Local(local) = self.base { - Place { local, projection: tcx.intern_place_elems(&self.projection) } + let mut projections = vec![]; + let mut ty = PlaceTy::from_ty(cx.local_decls[local].ty); + for projection in self.projection { + // Only preserve those opaque casts that actually go from an opaque type + // to another type. + if let ProjectionElem::OpaqueCast(t) = projection { + if let ty::Opaque(..) = ty.ty.kind() { + if t != ty.ty { + projections.push(ProjectionElem::OpaqueCast(t)); + } + } + } else { + projections.push(projection); + } + ty = ty.projection_ty(cx.tcx, projection); + } + Place { local, projection: cx.tcx.intern_place_elems(&projections) } } else { - self.expect_upvars_resolved(tcx, typeck_results).into_place(tcx, typeck_results) + self.expect_upvars_resolved(cx).into_place(cx) } } - fn expect_upvars_resolved<'a>( - self, - tcx: TyCtxt<'tcx>, - typeck_results: &'a ty::TypeckResults<'tcx>, - ) -> PlaceBuilder<'tcx> { - to_upvars_resolved_place_builder(self, tcx, typeck_results).unwrap() + fn expect_upvars_resolved(self, cx: &Builder<'_, 'tcx>) -> PlaceBuilder<'tcx> { + to_upvars_resolved_place_builder(self, cx).unwrap() } /// Attempts to resolve the `PlaceBuilder`. @@ -346,12 +364,11 @@ impl<'tcx> PlaceBuilder<'tcx> { /// not captured. This can happen because the final mir that will be /// generated doesn't require a read for this place. Failures will only /// happen inside closures. - pub(crate) fn try_upvars_resolved<'a>( + pub(crate) fn try_upvars_resolved( self, - tcx: TyCtxt<'tcx>, - typeck_results: &'a ty::TypeckResults<'tcx>, + cx: &Builder<'_, 'tcx>, ) -> Result<PlaceBuilder<'tcx>, PlaceBuilder<'tcx>> { - to_upvars_resolved_place_builder(self, tcx, typeck_results) + to_upvars_resolved_place_builder(self, cx) } pub(crate) fn base(&self) -> PlaceBase { @@ -411,7 +428,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { expr: &Expr<'tcx>, ) -> BlockAnd<Place<'tcx>> { let place_builder = unpack!(block = self.as_place_builder(block, expr)); - block.and(place_builder.into_place(self.tcx, self.typeck_results)) + block.and(place_builder.into_place(self)) } /// This is used when constructing a compound `Place`, so that we can avoid creating @@ -435,7 +452,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { expr: &Expr<'tcx>, ) -> BlockAnd<Place<'tcx>> { let place_builder = unpack!(block = self.as_read_only_place_builder(block, expr)); - block.and(place_builder.into_place(self.tcx, self.typeck_results)) + block.and(place_builder.into_place(self)) } /// This is used when constructing a compound `Place`, so that we can avoid creating @@ -530,7 +547,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { inferred_ty: expr.ty, }); - let place = place_builder.clone().into_place(this.tcx, this.typeck_results); + let place = place_builder.clone().into_place(this); this.cfg.push( block, Statement { @@ -682,7 +699,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { if is_outermost_index { self.read_fake_borrows(block, fake_borrow_temps, source_info) } else { - base_place = base_place.expect_upvars_resolved(self.tcx, self.typeck_results); + base_place = base_place.expect_upvars_resolved(self); self.add_fake_borrows_of_base( &base_place, block, @@ -710,12 +727,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let lt = self.temp(bool_ty, expr_span); // len = len(slice) - self.cfg.push_assign( - block, - source_info, - len, - Rvalue::Len(slice.into_place(self.tcx, self.typeck_results)), - ); + self.cfg.push_assign(block, source_info, len, Rvalue::Len(slice.into_place(self))); // lt = idx < len self.cfg.push_assign( block, @@ -795,6 +807,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { } ProjectionElem::Field(..) | ProjectionElem::Downcast(..) + | ProjectionElem::OpaqueCast(..) | ProjectionElem::ConstantIndex { .. } | ProjectionElem::Subslice { .. } => (), } diff --git a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs index 15f2d17c4e0..93f76333165 100644 --- a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs +++ b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs @@ -321,11 +321,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let place_builder = unpack!(block = this.as_place_builder(block, &this.thir[*thir_place])); - if let Ok(place_builder_resolved) = - place_builder.try_upvars_resolved(this.tcx, this.typeck_results) - { - let mir_place = - place_builder_resolved.into_place(this.tcx, this.typeck_results); + if let Ok(place_builder_resolved) = place_builder.try_upvars_resolved(this) { + let mir_place = place_builder_resolved.into_place(this); this.cfg.push_fake_read( block, this.source_info(this.tcx.hir().span(*hir_id)), @@ -616,8 +613,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // by the parent itself. The mutability of the current capture // is same as that of the capture in the parent closure. PlaceBase::Upvar { .. } => { - let enclosing_upvars_resolved = - arg_place_builder.clone().into_place(this.tcx, this.typeck_results); + let enclosing_upvars_resolved = arg_place_builder.clone().into_place(this); match enclosing_upvars_resolved.as_ref() { PlaceRef { @@ -654,7 +650,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { Mutability::Mut => BorrowKind::Mut { allow_two_phase_borrow: false }, }; - let arg_place = arg_place_builder.into_place(this.tcx, this.typeck_results); + let arg_place = arg_place_builder.into_place(this); this.cfg.push_assign( block, diff --git a/compiler/rustc_mir_build/src/build/expr/as_temp.rs b/compiler/rustc_mir_build/src/build/expr/as_temp.rs index 724b72f8769..dac8862647a 100644 --- a/compiler/rustc_mir_build/src/build/expr/as_temp.rs +++ b/compiler/rustc_mir_build/src/build/expr/as_temp.rs @@ -23,6 +23,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ensure_sufficient_stack(|| self.as_temp_inner(block, temp_lifetime, expr, mutability)) } + #[instrument(skip(self), level = "debug")] fn as_temp_inner( &mut self, mut block: BasicBlock, @@ -30,10 +31,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { expr: &Expr<'tcx>, mutability: Mutability, ) -> BlockAnd<Local> { - debug!( - "as_temp(block={:?}, temp_lifetime={:?}, expr={:?}, mutability={:?})", - block, temp_lifetime, expr, mutability - ); let this = self; let expr_span = expr.span; diff --git a/compiler/rustc_mir_build/src/build/expr/into.rs b/compiler/rustc_mir_build/src/build/expr/into.rs index 017d43d10a9..d1ef515b3d2 100644 --- a/compiler/rustc_mir_build/src/build/expr/into.rs +++ b/compiler/rustc_mir_build/src/build/expr/into.rs @@ -15,14 +15,13 @@ use std::iter; impl<'a, 'tcx> Builder<'a, 'tcx> { /// Compile `expr`, storing the result into `destination`, which /// is assumed to be uninitialized. + #[instrument(level = "debug", skip(self))] pub(crate) fn expr_into_dest( &mut self, destination: Place<'tcx>, mut block: BasicBlock, expr: &Expr<'tcx>, ) -> BlockAnd<()> { - debug!("expr_into_dest(destination={:?}, block={:?}, expr={:?})", destination, block, expr); - // since we frequently have to reference `self` from within a // closure, where `self` would be shadowed, it's easier to // just use the name `this` uniformly @@ -366,9 +365,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { None => { let place_builder = place_builder.clone(); this.consume_by_copy_or_move( - place_builder - .field(n, *ty) - .into_place(this.tcx, this.typeck_results), + place_builder.field(n, *ty).into_place(this), ) } }) diff --git a/compiler/rustc_mir_build/src/build/matches/mod.rs b/compiler/rustc_mir_build/src/build/matches/mod.rs index 7067a48b783..86ef666eac8 100644 --- a/compiler/rustc_mir_build/src/build/matches/mod.rs +++ b/compiler/rustc_mir_build/src/build/matches/mod.rs @@ -220,10 +220,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let cause_matched_place = FakeReadCause::ForMatchedPlace(None); let source_info = self.source_info(scrutinee_span); - if let Ok(scrutinee_builder) = - scrutinee_place_builder.clone().try_upvars_resolved(self.tcx, self.typeck_results) - { - let scrutinee_place = scrutinee_builder.into_place(self.tcx, self.typeck_results); + if let Ok(scrutinee_builder) = scrutinee_place_builder.clone().try_upvars_resolved(self) { + let scrutinee_place = scrutinee_builder.into_place(self); self.cfg.push_fake_read(block, source_info, cause_matched_place, scrutinee_place); } @@ -348,12 +346,10 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // ``` let mut opt_scrutinee_place: Option<(Option<&Place<'tcx>>, Span)> = None; let scrutinee_place: Place<'tcx>; - if let Ok(scrutinee_builder) = scrutinee_place_builder - .clone() - .try_upvars_resolved(this.tcx, this.typeck_results) + if let Ok(scrutinee_builder) = + scrutinee_place_builder.clone().try_upvars_resolved(this) { - scrutinee_place = - scrutinee_builder.into_place(this.tcx, this.typeck_results); + scrutinee_place = scrutinee_builder.into_place(this); opt_scrutinee_place = Some((Some(&scrutinee_place), scrutinee_span)); } let scope = this.declare_bindings( @@ -602,12 +598,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { while let Some(next) = { for binding in &candidate_ref.bindings { let local = self.var_local_id(binding.var_id, OutsideGuard); - - let Some(box LocalInfo::User(ClearCrossCrate::Set(BindingForm::Var( - VarBindingForm { opt_match_place: Some((ref mut match_place, _)), .. }, - )))) = self.local_decls[local].local_info else { - bug!("Let binding to non-user variable.") - }; // `try_upvars_resolved` may fail if it is unable to resolve the given // `PlaceBuilder` inside a closure. In this case, we don't want to include // a scrutinee place. `scrutinee_place_builder` will fail for destructured @@ -622,10 +612,15 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // let (v1, v2) = foo; // }; // ``` - if let Ok(match_pair_resolved) = - initializer.clone().try_upvars_resolved(self.tcx, self.typeck_results) - { - let place = match_pair_resolved.into_place(self.tcx, self.typeck_results); + if let Ok(match_pair_resolved) = initializer.clone().try_upvars_resolved(self) { + let place = match_pair_resolved.into_place(self); + + let Some(box LocalInfo::User(ClearCrossCrate::Set(BindingForm::Var( + VarBindingForm { opt_match_place: Some((ref mut match_place, _)), .. }, + )))) = self.local_decls[local].local_info else { + bug!("Let binding to non-user variable.") + }; + *match_place = Some(place); } } @@ -654,6 +649,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { /// scope for the bindings in these patterns, if such a scope had to be /// created. NOTE: Declaring the bindings should always be done in their /// drop scope. + #[instrument(skip(self), level = "debug")] pub(crate) fn declare_bindings( &mut self, mut visibility_scope: Option<SourceScope>, @@ -662,7 +658,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { has_guard: ArmHasGuard, opt_match_place: Option<(Option<&Place<'tcx>>, Span)>, ) -> Option<SourceScope> { - debug!("declare_bindings: pattern={:?}", pattern); self.visit_primary_bindings( &pattern, UserTypeProjections::none(), @@ -872,7 +867,7 @@ impl<'tcx, 'pat> Candidate<'pat, 'tcx> { Candidate { span: pattern.span, has_guard, - match_pairs: smallvec![MatchPair { place, pattern }], + match_pairs: smallvec![MatchPair::new(place, pattern)], bindings: Vec::new(), ascriptions: Vec::new(), subcandidates: Vec::new(), @@ -1048,6 +1043,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { /// if `x.0` matches `false` (for the third arm). In the (impossible at /// runtime) case when `x.0` is now `true`, we branch to /// `otherwise_block`. + #[instrument(skip(self, fake_borrows), level = "debug")] fn match_candidates<'pat>( &mut self, span: Span, @@ -1057,11 +1053,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { candidates: &mut [&mut Candidate<'pat, 'tcx>], fake_borrows: &mut Option<FxIndexSet<Place<'tcx>>>, ) { - debug!( - "matched_candidate(span={:?}, candidates={:?}, start_block={:?}, otherwise_block={:?})", - span, candidates, start_block, otherwise_block, - ); - // Start by simplifying candidates. Once this process is complete, all // the match pairs which remain require some form of test, whether it // be a switch or pattern comparison. @@ -1380,6 +1371,10 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ) } + #[instrument( + skip(self, otherwise, or_span, place, fake_borrows, candidate, pats), + level = "debug" + )] fn test_or_pattern<'pat>( &mut self, candidate: &mut Candidate<'pat, 'tcx>, @@ -1389,7 +1384,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { place: PlaceBuilder<'tcx>, fake_borrows: &mut Option<FxIndexSet<Place<'tcx>>>, ) { - debug!("test_or_pattern:\ncandidate={:#?}\npats={:#?}", candidate, pats); + debug!("candidate={:#?}\npats={:#?}", candidate, pats); let mut or_candidates: Vec<_> = pats .iter() .map(|pat| Candidate::new(place.clone(), pat, candidate.has_guard)) @@ -1605,9 +1600,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // Insert a Shallow borrow of any places that is switched on. if let Some(fb) = fake_borrows && let Ok(match_place_resolved) = - match_place.clone().try_upvars_resolved(self.tcx, self.typeck_results) + match_place.clone().try_upvars_resolved(self) { - let resolved_place = match_place_resolved.into_place(self.tcx, self.typeck_results); + let resolved_place = match_place_resolved.into_place(self); fb.insert(resolved_place); } @@ -1634,9 +1629,14 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { candidates = rest; } // at least the first candidate ought to be tested - assert!(total_candidate_count > candidates.len()); - debug!("test_candidates: tested_candidates: {}", total_candidate_count - candidates.len()); - debug!("test_candidates: untested_candidates: {}", candidates.len()); + assert!( + total_candidate_count > candidates.len(), + "{}, {:#?}", + total_candidate_count, + candidates + ); + debug!("tested_candidates: {}", total_candidate_count - candidates.len()); + debug!("untested_candidates: {}", candidates.len()); // HACK(matthewjasper) This is a closure so that we can let the test // create its blocks before the rest of the match. This currently @@ -1794,10 +1794,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ); let mut opt_expr_place: Option<(Option<&Place<'tcx>>, Span)> = None; let expr_place: Place<'tcx>; - if let Ok(expr_builder) = - expr_place_builder.try_upvars_resolved(self.tcx, self.typeck_results) - { - expr_place = expr_builder.into_place(self.tcx, self.typeck_results); + if let Ok(expr_builder) = expr_place_builder.try_upvars_resolved(self) { + expr_place = expr_builder.into_place(self); opt_expr_place = Some((Some(&expr_place), expr_span)); } let otherwise_post_guard_block = otherwise_candidate.pre_binding_block.unwrap(); @@ -2195,6 +2193,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { /// first local is a binding for occurrences of `var` in the guard, which /// will have type `&T`. The second local is a binding for occurrences of /// `var` in the arm body, which will have type `T`. + #[instrument(skip(self), level = "debug")] fn declare_binding( &mut self, source_info: SourceInfo, @@ -2209,19 +2208,12 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { opt_match_place: Option<(Option<Place<'tcx>>, Span)>, pat_span: Span, ) { - debug!( - "declare_binding(var_id={:?}, name={:?}, mode={:?}, var_ty={:?}, \ - visibility_scope={:?}, source_info={:?})", - var_id, name, mode, var_ty, visibility_scope, source_info - ); - let tcx = self.tcx; let debug_source_info = SourceInfo { span: source_info.span, scope: visibility_scope }; let binding_mode = match mode { BindingMode::ByValue => ty::BindingMode::BindByValue(mutability), BindingMode::ByRef(_) => ty::BindingMode::BindByReference(mutability), }; - debug!("declare_binding: user_ty={:?}", user_ty); let local = LocalDecl::<'tcx> { mutability, ty: var_ty, @@ -2271,7 +2263,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { } else { LocalsForNode::One(for_arm_body) }; - debug!("declare_binding: vars={:?}", locals); + debug!(?locals); self.var_indices.insert(var_id, locals); } diff --git a/compiler/rustc_mir_build/src/build/matches/simplify.rs b/compiler/rustc_mir_build/src/build/matches/simplify.rs index c6298904140..6fa817da28a 100644 --- a/compiler/rustc_mir_build/src/build/matches/simplify.rs +++ b/compiler/rustc_mir_build/src/build/matches/simplify.rs @@ -37,12 +37,13 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { /// /// only generates a single switch. If this happens this method returns /// `true`. + #[instrument(skip(self, candidate), level = "debug")] pub(super) fn simplify_candidate<'pat>( &mut self, candidate: &mut Candidate<'pat, 'tcx>, ) -> bool { // repeatedly simplify match pairs until fixed point is reached - debug!(?candidate, "simplify_candidate"); + debug!("{:#?}", candidate); // existing_bindings and new_bindings exists to keep the semantics in order. // Reversing the binding order for bindings after `@` changes the binding order in places @@ -155,12 +156,10 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ascription: thir::Ascription { ref annotation, variance }, } => { // Apply the type ascription to the value at `match_pair.place`, which is the - if let Ok(place_resolved) = - match_pair.place.clone().try_upvars_resolved(self.tcx, self.typeck_results) - { + if let Ok(place_resolved) = match_pair.place.clone().try_upvars_resolved(self) { candidate.ascriptions.push(Ascription { annotation: annotation.clone(), - source: place_resolved.into_place(self.tcx, self.typeck_results), + source: place_resolved.into_place(self), variance, }); } @@ -184,12 +183,10 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { ref subpattern, is_primary: _, } => { - if let Ok(place_resolved) = - match_pair.place.clone().try_upvars_resolved(self.tcx, self.typeck_results) - { + if let Ok(place_resolved) = match_pair.place.clone().try_upvars_resolved(self) { candidate.bindings.push(Binding { span: match_pair.pattern.span, - source: place_resolved.into_place(self.tcx, self.typeck_results), + source: place_resolved.into_place(self), var_id: var, binding_mode: mode, }); diff --git a/compiler/rustc_mir_build/src/build/matches/test.rs b/compiler/rustc_mir_build/src/build/matches/test.rs index 598da80c574..63acd731db7 100644 --- a/compiler/rustc_mir_build/src/build/matches/test.rs +++ b/compiler/rustc_mir_build/src/build/matches/test.rs @@ -144,6 +144,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { } } + #[instrument(skip(self, make_target_blocks, place_builder), level = "debug")] pub(super) fn perform_test( &mut self, match_start_span: Span, @@ -153,21 +154,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { test: &Test<'tcx>, make_target_blocks: impl FnOnce(&mut Self) -> Vec<BasicBlock>, ) { - let place: Place<'tcx>; - if let Ok(test_place_builder) = - place_builder.try_upvars_resolved(self.tcx, self.typeck_results) - { - place = test_place_builder.into_place(self.tcx, self.typeck_results); - } else { - return; - } - debug!( - "perform_test({:?}, {:?}: {:?}, {:?})", - block, - place, - place.ty(&self.local_decls, self.tcx), - test - ); + let place = place_builder.into_place(self); + let place_ty = place.ty(&self.local_decls, self.tcx); + debug!(?place, ?place_ty,); let source_info = self.source_info(test.span); match test.kind { @@ -735,9 +724,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // So, if we have a match-pattern like `x @ Enum::Variant(P1, P2)`, // we want to create a set of derived match-patterns like // `(x as Variant).0 @ P1` and `(x as Variant).1 @ P1`. - let elem = - ProjectionElem::Downcast(Some(adt_def.variant(variant_index).name), variant_index); - let downcast_place = match_pair.place.project(elem); // `(x as Variant)` + let downcast_place = match_pair.place.downcast(adt_def, variant_index); // `(x as Variant)` let consequent_match_pairs = subpatterns.iter().map(|subpattern| { // e.g., `(x as Variant).0` let place = downcast_place.clone().field(subpattern.field, subpattern.pattern.ty); diff --git a/compiler/rustc_mir_build/src/build/matches/util.rs b/compiler/rustc_mir_build/src/build/matches/util.rs index 9a1e98d3bb1..4a7edc517f4 100644 --- a/compiler/rustc_mir_build/src/build/matches/util.rs +++ b/compiler/rustc_mir_build/src/build/matches/util.rs @@ -31,21 +31,15 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { suffix: &'pat [Pat<'tcx>], ) { let tcx = self.tcx; - let (min_length, exact_size) = if let Ok(place_resolved) = - place.clone().try_upvars_resolved(tcx, self.typeck_results) - { - match place_resolved - .into_place(tcx, self.typeck_results) - .ty(&self.local_decls, tcx) - .ty - .kind() - { - ty::Array(_, length) => (length.eval_usize(tcx, self.param_env), true), - _ => ((prefix.len() + suffix.len()).try_into().unwrap(), false), - } - } else { - ((prefix.len() + suffix.len()).try_into().unwrap(), false) - }; + let (min_length, exact_size) = + if let Ok(place_resolved) = place.clone().try_upvars_resolved(self) { + match place_resolved.into_place(self).ty(&self.local_decls, tcx).ty.kind() { + ty::Array(_, length) => (length.eval_usize(tcx, self.param_env), true), + _ => ((prefix.len() + suffix.len()).try_into().unwrap(), false), + } + } else { + ((prefix.len() + suffix.len()).try_into().unwrap(), false) + }; match_pairs.extend(prefix.iter().enumerate().map(|(idx, subpattern)| { let elem = @@ -100,10 +94,14 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { } impl<'pat, 'tcx> MatchPair<'pat, 'tcx> { - pub(crate) fn new( + pub(in crate::build) fn new( place: PlaceBuilder<'tcx>, pattern: &'pat Pat<'tcx>, ) -> MatchPair<'pat, 'tcx> { + // Force the place type to the pattern's type. + // FIXME(oli-obk): only do this when we don't already know the place type. + // FIXME(oli-obk): can we use this to simplify slice/array pattern hacks? + let place = place.project(ProjectionElem::OpaqueCast(pattern.ty)); MatchPair { place, pattern } } } diff --git a/compiler/rustc_mir_build/src/build/scope.rs b/compiler/rustc_mir_build/src/build/scope.rs index b9fd8c50e6a..ab37c480285 100644 --- a/compiler/rustc_mir_build/src/build/scope.rs +++ b/compiler/rustc_mir_build/src/build/scope.rs @@ -553,6 +553,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { /// Convenience wrapper that pushes a scope and then executes `f` /// to build its contents, popping the scope afterwards. + #[instrument(skip(self, f), level = "debug")] pub(crate) fn in_scope<F, R>( &mut self, region_scope: (region::Scope, SourceInfo), @@ -562,7 +563,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { where F: FnOnce(&mut Builder<'a, 'tcx>) -> BlockAnd<R>, { - debug!("in_scope(region_scope={:?})", region_scope); let source_scope = self.source_scope; let tcx = self.tcx; if let LintLevel::Explicit(current_hir_id) = lint_level { @@ -589,7 +589,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { let rv = unpack!(block = f(self)); unpack!(block = self.pop_scope(region_scope, block)); self.source_scope = source_scope; - debug!("in_scope: exiting region_scope={:?} block={:?}", region_scope, block); + debug!(?block); block.and(rv) } diff --git a/compiler/rustc_mir_build/src/thir/cx/expr.rs b/compiler/rustc_mir_build/src/thir/cx/expr.rs index 4eb3607e9cc..05da33caa91 100644 --- a/compiler/rustc_mir_build/src/thir/cx/expr.rs +++ b/compiler/rustc_mir_build/src/thir/cx/expr.rs @@ -48,6 +48,8 @@ impl<'tcx> Cx<'tcx> { _ => None, }; + trace!(?expr.ty); + // Now apply adjustments, if any. for adjustment in self.typeck_results.expr_adjustments(hir_expr) { trace!(?expr, ?adjustment); @@ -56,6 +58,8 @@ impl<'tcx> Cx<'tcx> { self.apply_adjustment(hir_expr, expr, adjustment, adjustment_span.unwrap_or(span)); } + trace!(?expr.ty, "after adjustments"); + // Next, wrap this up in the expr's scope. expr = Expr { temp_lifetime, diff --git a/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs b/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs index 60db98073a3..c0fd19cf71c 100644 --- a/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs +++ b/compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs @@ -1202,35 +1202,32 @@ impl<'p, 'tcx> Fields<'p, 'tcx> { /// Creates a new list of wildcard fields for a given constructor. The result must have a /// length of `constructor.arity()`. - pub(super) fn wildcards( - cx: &MatchCheckCtxt<'p, 'tcx>, - ty: Ty<'tcx>, - constructor: &Constructor<'tcx>, - ) -> Self { + #[instrument(level = "trace")] + pub(super) fn wildcards(pcx: PatCtxt<'_, 'p, 'tcx>, constructor: &Constructor<'tcx>) -> Self { let ret = match constructor { - Single | Variant(_) => match ty.kind() { - ty::Tuple(fs) => Fields::wildcards_from_tys(cx, fs.iter()), - ty::Ref(_, rty, _) => Fields::wildcards_from_tys(cx, once(*rty)), + Single | Variant(_) => match pcx.ty.kind() { + ty::Tuple(fs) => Fields::wildcards_from_tys(pcx.cx, fs.iter()), + ty::Ref(_, rty, _) => Fields::wildcards_from_tys(pcx.cx, once(*rty)), ty::Adt(adt, substs) => { if adt.is_box() { // The only legal patterns of type `Box` (outside `std`) are `_` and box // patterns. If we're here we can assume this is a box pattern. - Fields::wildcards_from_tys(cx, once(substs.type_at(0))) + Fields::wildcards_from_tys(pcx.cx, once(substs.type_at(0))) } else { let variant = &adt.variant(constructor.variant_index_for_adt(*adt)); - let tys = Fields::list_variant_nonhidden_fields(cx, ty, variant) + let tys = Fields::list_variant_nonhidden_fields(pcx.cx, pcx.ty, variant) .map(|(_, ty)| ty); - Fields::wildcards_from_tys(cx, tys) + Fields::wildcards_from_tys(pcx.cx, tys) } } - _ => bug!("Unexpected type for `Single` constructor: {:?}", ty), + _ => bug!("Unexpected type for `Single` constructor: {:?}", pcx), }, - Slice(slice) => match *ty.kind() { + Slice(slice) => match *pcx.ty.kind() { ty::Slice(ty) | ty::Array(ty, _) => { let arity = slice.arity(); - Fields::wildcards_from_tys(cx, (0..arity).map(|_| ty)) + Fields::wildcards_from_tys(pcx.cx, (0..arity).map(|_| ty)) } - _ => bug!("bad slice pattern {:?} {:?}", constructor, ty), + _ => bug!("bad slice pattern {:?} {:?}", constructor, pcx), }, Str(..) | FloatRange(..) @@ -1243,7 +1240,7 @@ impl<'p, 'tcx> Fields<'p, 'tcx> { bug!("called `Fields::wildcards` on an `Or` ctor") } }; - debug!("Fields::wildcards({:?}, {:?}) = {:#?}", constructor, ty, ret); + debug!(?ret); ret } @@ -1286,7 +1283,7 @@ impl<'p, 'tcx> DeconstructedPat<'p, 'tcx> { /// For example, if `ctor` is a `Constructor::Variant` for `Option::Some`, we get the pattern /// `Some(_)`. pub(super) fn wild_from_ctor(pcx: PatCtxt<'_, 'p, 'tcx>, ctor: Constructor<'tcx>) -> Self { - let fields = Fields::wildcards(pcx.cx, pcx.ty, &ctor); + let fields = Fields::wildcards(pcx, &ctor); DeconstructedPat::new(ctor, fields, pcx.ty, DUMMY_SP) } @@ -1553,13 +1550,13 @@ impl<'p, 'tcx> DeconstructedPat<'p, 'tcx> { /// `other_ctor` can be different from `self.ctor`, but must be covered by it. pub(super) fn specialize<'a>( &'a self, - cx: &MatchCheckCtxt<'p, 'tcx>, + pcx: PatCtxt<'_, 'p, 'tcx>, other_ctor: &Constructor<'tcx>, ) -> SmallVec<[&'p DeconstructedPat<'p, 'tcx>; 2]> { match (&self.ctor, other_ctor) { (Wildcard, _) => { // We return a wildcard for each field of `other_ctor`. - Fields::wildcards(cx, self.ty, other_ctor).iter_patterns().collect() + Fields::wildcards(pcx, other_ctor).iter_patterns().collect() } (Slice(self_slice), Slice(other_slice)) if self_slice.arity() != other_slice.arity() => @@ -1578,7 +1575,7 @@ impl<'p, 'tcx> DeconstructedPat<'p, 'tcx> { let prefix = &self.fields.fields[..prefix]; let suffix = &self.fields.fields[self_slice.arity() - suffix..]; let wildcard: &_ = - cx.pattern_arena.alloc(DeconstructedPat::wildcard(inner_ty)); + pcx.cx.pattern_arena.alloc(DeconstructedPat::wildcard(inner_ty)); let extra_wildcards = other_slice.arity() - self_slice.arity(); let extra_wildcards = (0..extra_wildcards).map(|_| wildcard); prefix.iter().chain(extra_wildcards).chain(suffix).collect() diff --git a/compiler/rustc_mir_build/src/thir/pattern/mod.rs b/compiler/rustc_mir_build/src/thir/pattern/mod.rs index a13748a2d47..7d22f7b69d8 100644 --- a/compiler/rustc_mir_build/src/thir/pattern/mod.rs +++ b/compiler/rustc_mir_build/src/thir/pattern/mod.rs @@ -196,6 +196,7 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> { } } + #[instrument(skip(self), level = "debug")] fn lower_pattern_unadjusted(&mut self, pat: &'tcx hir::Pat<'tcx>) -> Pat<'tcx> { let mut ty = self.typeck_results.node_type(pat.hir_id); diff --git a/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs b/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs index 9e7a267ecbd..f27ec22a8de 100644 --- a/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs +++ b/compiler/rustc_mir_build/src/thir/pattern/usefulness.rs @@ -411,12 +411,12 @@ impl<'p, 'tcx> PatStack<'p, 'tcx> { /// This is roughly the inverse of `Constructor::apply`. fn pop_head_constructor( &self, - cx: &MatchCheckCtxt<'p, 'tcx>, + pcx: PatCtxt<'_, 'p, 'tcx>, ctor: &Constructor<'tcx>, ) -> PatStack<'p, 'tcx> { // We pop the head pattern and push the new fields extracted from the arguments of // `self.head()`. - let mut new_fields: SmallVec<[_; 2]> = self.head().specialize(cx, ctor); + let mut new_fields: SmallVec<[_; 2]> = self.head().specialize(pcx, ctor); new_fields.extend_from_slice(&self.pats[1..]); PatStack::from_vec(new_fields) } @@ -475,7 +475,7 @@ impl<'p, 'tcx> Matrix<'p, 'tcx> { let mut matrix = Matrix::empty(); for row in &self.patterns { if ctor.is_covered_by(pcx, row.head().ctor()) { - let new_row = row.pop_head_constructor(pcx.cx, ctor); + let new_row = row.pop_head_constructor(pcx, ctor); matrix.push(new_row); } } @@ -786,7 +786,7 @@ fn is_useful<'p, 'tcx>( is_under_guard: bool, is_top_level: bool, ) -> Usefulness<'p, 'tcx> { - debug!("matrix,v={:?}{:?}", matrix, v); + debug!(?matrix, ?v); let Matrix { patterns: rows, .. } = matrix; // The base case. We are pattern-matching on () and the return value is @@ -806,11 +806,6 @@ fn is_useful<'p, 'tcx>( debug_assert!(rows.iter().all(|r| r.len() == v.len())); - let ty = v.head().ty(); - let is_non_exhaustive = cx.is_foreign_non_exhaustive_enum(ty); - debug!("v.head: {:?}, v.span: {:?}", v.head(), v.head().span()); - let pcx = PatCtxt { cx, ty, span: v.head().span(), is_top_level, is_non_exhaustive }; - // If the first pattern is an or-pattern, expand it. let mut ret = Usefulness::new_not_useful(witness_preference); if v.head().is_or_pat() { @@ -832,6 +827,19 @@ fn is_useful<'p, 'tcx>( } } } else { + let mut ty = v.head().ty(); + + // Opaque types can't get destructured/split, but the patterns can + // actually hint at hidden types, so we use the patterns' types instead. + if let ty::Opaque(..) = v.head().ty().kind() { + if let Some(row) = rows.first() { + ty = row.head().ty(); + } + } + let is_non_exhaustive = cx.is_foreign_non_exhaustive_enum(ty); + debug!("v.head: {:?}, v.span: {:?}", v.head(), v.head().span()); + let pcx = PatCtxt { cx, ty, span: v.head().span(), is_top_level, is_non_exhaustive }; + let v_ctor = v.head().ctor(); debug!(?v_ctor); if let Constructor::IntRange(ctor_range) = &v_ctor { @@ -853,7 +861,7 @@ fn is_useful<'p, 'tcx>( debug!("specialize({:?})", ctor); // We cache the result of `Fields::wildcards` because it is used a lot. let spec_matrix = start_matrix.specialize_constructor(pcx, &ctor); - let v = v.pop_head_constructor(cx, &ctor); + let v = v.pop_head_constructor(pcx, &ctor); let usefulness = ensure_sufficient_stack(|| { is_useful(cx, &spec_matrix, &v, witness_preference, hir_id, is_under_guard, false) }); |