diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_borrowck/src/nll.rs | 37 | ||||
| -rw-r--r-- | compiler/rustc_borrowck/src/region_infer/mod.rs | 12 | ||||
| -rw-r--r-- | compiler/rustc_borrowck/src/region_infer/values.rs | 62 | ||||
| -rw-r--r-- | compiler/rustc_borrowck/src/type_check/liveness/trace.rs | 64 | ||||
| -rw-r--r-- | compiler/rustc_borrowck/src/type_check/mod.rs | 16 |
5 files changed, 94 insertions, 97 deletions
diff --git a/compiler/rustc_borrowck/src/nll.rs b/compiler/rustc_borrowck/src/nll.rs index f12975c3f09..7023a571a26 100644 --- a/compiler/rustc_borrowck/src/nll.rs +++ b/compiler/rustc_borrowck/src/nll.rs @@ -101,26 +101,22 @@ pub(crate) fn compute_regions<'cx, 'tcx>( let elements = &Rc::new(RegionValueElements::new(body)); // Run the MIR type-checker. - let MirTypeckResults { - constraints, - universal_region_relations, - opaque_type_values, - live_loans, - } = type_check::type_check( - infcx, - param_env, - body, - promoted, - &universal_regions, - location_table, - borrow_set, - &mut all_facts, - flow_inits, - move_data, - elements, - upvars, - polonius_input, - ); + let MirTypeckResults { constraints, universal_region_relations, opaque_type_values } = + type_check::type_check( + infcx, + param_env, + body, + promoted, + &universal_regions, + location_table, + borrow_set, + &mut all_facts, + flow_inits, + move_data, + elements, + upvars, + polonius_input, + ); // Create the region inference context, taking ownership of the // region inference data that was contained in `infcx`, and the @@ -161,7 +157,6 @@ pub(crate) fn compute_regions<'cx, 'tcx>( type_tests, liveness_constraints, elements, - live_loans, ); // If requested: dump NLL facts, and run legacy polonius analysis. diff --git a/compiler/rustc_borrowck/src/region_infer/mod.rs b/compiler/rustc_borrowck/src/region_infer/mod.rs index 1c082b7a56c..b308cd82e54 100644 --- a/compiler/rustc_borrowck/src/region_infer/mod.rs +++ b/compiler/rustc_borrowck/src/region_infer/mod.rs @@ -7,7 +7,6 @@ use rustc_data_structures::fx::{FxIndexMap, FxIndexSet}; use rustc_data_structures::graph::scc::Sccs; use rustc_errors::Diagnostic; use rustc_hir::def_id::CRATE_DEF_ID; -use rustc_index::bit_set::SparseBitMatrix; use rustc_index::{IndexSlice, IndexVec}; use rustc_infer::infer::outlives::test_type_match; use rustc_infer::infer::region_constraints::{GenericKind, VarInfos, VerifyBound, VerifyIfEq}; @@ -31,8 +30,8 @@ use crate::{ nll::PoloniusOutput, region_infer::reverse_sccs::ReverseSccGraph, region_infer::values::{ - LivenessValues, PlaceholderIndices, PointIndex, RegionElement, RegionValueElements, - RegionValues, ToElementIndex, + LivenessValues, PlaceholderIndices, RegionElement, RegionValueElements, RegionValues, + ToElementIndex, }, type_check::{free_region_relations::UniversalRegionRelations, Locations}, universal_regions::UniversalRegions, @@ -120,9 +119,6 @@ pub struct RegionInferenceContext<'tcx> { /// Information about how the universally quantified regions in /// scope on this function relate to one another. universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>, - - /// The set of loans that are live at a given point in the CFG, when using `-Zpolonius=next`. - live_loans: SparseBitMatrix<PointIndex, BorrowIndex>, } /// Each time that `apply_member_constraint` is successful, it appends @@ -335,7 +331,6 @@ impl<'tcx> RegionInferenceContext<'tcx> { type_tests: Vec<TypeTest<'tcx>>, liveness_constraints: LivenessValues, elements: &Rc<RegionValueElements>, - live_loans: SparseBitMatrix<PointIndex, BorrowIndex>, ) -> Self { debug!("universal_regions: {:#?}", universal_regions); debug!("outlives constraints: {:#?}", outlives_constraints); @@ -389,7 +384,6 @@ impl<'tcx> RegionInferenceContext<'tcx> { type_tests, universal_regions, universal_region_relations, - live_loans, }; result.init_free_and_bound_regions(); @@ -2325,7 +2319,7 @@ impl<'tcx> RegionInferenceContext<'tcx> { /// Note: for now, the sets of live loans is only available when using `-Zpolonius=next`. pub(crate) fn is_loan_live_at(&self, loan_idx: BorrowIndex, location: Location) -> bool { let point = self.liveness_constraints.point_from_location(location); - self.live_loans.contains(point, loan_idx) + self.liveness_constraints.is_loan_live_at(loan_idx, point) } } diff --git a/compiler/rustc_borrowck/src/region_infer/values.rs b/compiler/rustc_borrowck/src/region_infer/values.rs index 41ae65268f2..dc3ee849d00 100644 --- a/compiler/rustc_borrowck/src/region_infer/values.rs +++ b/compiler/rustc_borrowck/src/region_infer/values.rs @@ -11,6 +11,8 @@ use rustc_middle::ty::{self, RegionVid}; use std::fmt::Debug; use std::rc::Rc; +use crate::dataflow::BorrowIndex; + /// Maps between a `Location` and a `PointIndex` (and vice versa). pub(crate) struct RegionValueElements { /// For each basic block, how many points are contained within? @@ -120,14 +122,45 @@ pub(crate) enum RegionElement { /// Records the CFG locations where each region is live. When we initially compute liveness, we use /// an interval matrix storing liveness ranges for each region-vid. pub(crate) struct LivenessValues { + /// The map from locations to points. elements: Rc<RegionValueElements>, + + /// For each region: the points where it is live. points: SparseIntervalMatrix<RegionVid, PointIndex>, + + /// When using `-Zpolonius=next`, for each point: the loans flowing into the live regions at + /// that point. + pub(crate) loans: Option<LiveLoans>, +} + +/// Data used to compute the loans that are live at a given point in the CFG, when using +/// `-Zpolonius=next`. +pub(crate) struct LiveLoans { + /// The set of loans that flow into a given region. When individual regions are marked as live + /// in the CFG, these inflowing loans are recorded as live. + pub(crate) inflowing_loans: SparseBitMatrix<RegionVid, BorrowIndex>, + + /// The set of loans that are live at a given point in the CFG. + pub(crate) live_loans: SparseBitMatrix<PointIndex, BorrowIndex>, +} + +impl LiveLoans { + pub(crate) fn new(num_loans: usize) -> Self { + LiveLoans { + live_loans: SparseBitMatrix::new(num_loans), + inflowing_loans: SparseBitMatrix::new(num_loans), + } + } } impl LivenessValues { /// Create an empty map of regions to locations where they're live. pub(crate) fn new(elements: Rc<RegionValueElements>) -> Self { - Self { points: SparseIntervalMatrix::new(elements.num_points), elements } + LivenessValues { + points: SparseIntervalMatrix::new(elements.num_points), + elements, + loans: None, + } } /// Iterate through each region that has a value in this set. @@ -140,12 +173,30 @@ impl LivenessValues { debug!("LivenessValues::add_location(region={:?}, location={:?})", region, location); let point = self.elements.point_from_location(location); self.points.insert(region, point); + + // When available, record the loans flowing into this region as live at the given point. + if let Some(loans) = self.loans.as_mut() { + if let Some(inflowing) = loans.inflowing_loans.row(region) { + loans.live_loans.union_row(point, inflowing); + } + } } /// Records `region` as being live at all the given `points`. pub(crate) fn add_points(&mut self, region: RegionVid, points: &IntervalSet<PointIndex>) { debug!("LivenessValues::add_points(region={:?}, points={:?})", region, points); self.points.union_row(region, points); + + // When available, record the loans flowing into this region as live at the given points. + if let Some(loans) = self.loans.as_mut() { + if let Some(inflowing) = loans.inflowing_loans.row(region) { + if !inflowing.is_empty() { + for point in points.iter() { + loans.live_loans.union_row(point, inflowing); + } + } + } + } } /// Records `region` as being live at all the control-flow points. @@ -185,6 +236,15 @@ impl LivenessValues { pub(crate) fn point_from_location(&self, location: Location) -> PointIndex { self.elements.point_from_location(location) } + + /// When using `-Zpolonius=next`, returns whether the `loan_idx` is live at the given `point`. + pub(crate) fn is_loan_live_at(&self, loan_idx: BorrowIndex, point: PointIndex) -> bool { + self.loans + .as_ref() + .expect("Accessing live loans requires `-Zpolonius=next`") + .live_loans + .contains(point, loan_idx) + } } /// Maps from `ty::PlaceholderRegion` values that are used in the rest of diff --git a/compiler/rustc_borrowck/src/type_check/liveness/trace.rs b/compiler/rustc_borrowck/src/type_check/liveness/trace.rs index d6e50d971ca..c718d57bec3 100644 --- a/compiler/rustc_borrowck/src/type_check/liveness/trace.rs +++ b/compiler/rustc_borrowck/src/type_check/liveness/trace.rs @@ -1,12 +1,12 @@ use rustc_data_structures::fx::{FxIndexMap, FxIndexSet}; use rustc_data_structures::graph::WithSuccessors; -use rustc_index::bit_set::{HybridBitSet, SparseBitMatrix}; +use rustc_index::bit_set::HybridBitSet; use rustc_index::interval::IntervalSet; use rustc_infer::infer::canonical::QueryRegionConstraints; use rustc_infer::infer::outlives::for_liveness; use rustc_middle::mir::{BasicBlock, Body, ConstraintCategory, Local, Location}; use rustc_middle::traits::query::DropckOutlivesResult; -use rustc_middle::ty::{RegionVid, Ty, TyCtxt, TypeVisitable, TypeVisitableExt}; +use rustc_middle::ty::{Ty, TyCtxt, TypeVisitable, TypeVisitableExt}; use rustc_span::DUMMY_SP; use rustc_trait_selection::traits::query::type_op::outlives::DropckOutlives; use rustc_trait_selection::traits::query::type_op::{TypeOp, TypeOpOutput}; @@ -16,9 +16,8 @@ use rustc_mir_dataflow::impls::MaybeInitializedPlaces; use rustc_mir_dataflow::move_paths::{HasMoveData, MoveData, MovePathIndex}; use rustc_mir_dataflow::ResultsCursor; -use crate::dataflow::BorrowIndex; use crate::{ - region_infer::values::{self, PointIndex, RegionValueElements}, + region_infer::values::{self, LiveLoans, PointIndex, RegionValueElements}, type_check::liveness::local_use_map::LocalUseMap, type_check::liveness::polonius, type_check::NormalizeLocation, @@ -52,15 +51,12 @@ pub(super) fn trace<'mir, 'tcx>( let local_use_map = &LocalUseMap::build(&relevant_live_locals, elements, body); // When using `-Zpolonius=next`, compute the set of loans that can reach a given region. - let num_loans = typeck.borrowck_context.borrow_set.len(); - let mut inflowing_loans = SparseBitMatrix::new(num_loans); if typeck.tcx().sess.opts.unstable_opts.polonius.is_next_enabled() { - let borrowck_context = &typeck.borrowck_context; + let borrowck_context = &mut typeck.borrowck_context; let borrow_set = &borrowck_context.borrow_set; + let mut live_loans = LiveLoans::new(borrow_set.len()); let outlives_constraints = &borrowck_context.constraints.outlives_constraints; - - let num_region_vars = typeck.infcx.num_region_vars(); - let graph = outlives_constraints.graph(num_region_vars); + let graph = outlives_constraints.graph(typeck.infcx.num_region_vars()); let region_graph = graph.region_graph(outlives_constraints, borrowck_context.universal_regions.fr_static); @@ -73,9 +69,13 @@ pub(super) fn trace<'mir, 'tcx>( continue; } - inflowing_loans.insert(succ, loan); + live_loans.inflowing_loans.insert(succ, loan); } } + + // Store the inflowing loans in the liveness constraints: they will be used to compute live + // loans when liveness data is recorded there. + borrowck_context.constraints.liveness_constraints.loans = Some(live_loans); }; let cx = LivenessContext { @@ -86,7 +86,6 @@ pub(super) fn trace<'mir, 'tcx>( local_use_map, move_data, drop_data: FxIndexMap::default(), - inflowing_loans, }; let mut results = LivenessResults::new(cx); @@ -124,9 +123,6 @@ struct LivenessContext<'me, 'typeck, 'flow, 'tcx> { /// Index indicating where each variable is assigned, used, or /// dropped. local_use_map: &'me LocalUseMap, - - /// Set of loans that flow into a given region, when using `-Zpolonius=next`. - inflowing_loans: SparseBitMatrix<RegionVid, BorrowIndex>, } struct DropData<'tcx> { @@ -517,14 +513,7 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> { live_at: &IntervalSet<PointIndex>, ) { debug!("add_use_live_facts_for(value={:?})", value); - - Self::make_all_regions_live( - self.elements, - self.typeck, - value, - live_at, - &self.inflowing_loans, - ); + Self::make_all_regions_live(self.elements, self.typeck, value, live_at); } /// Some variable with type `live_ty` is "drop live" at `location` @@ -575,14 +564,7 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> { // All things in the `outlives` array may be touched by // the destructor and must be live at this point. for &kind in &drop_data.dropck_result.kinds { - Self::make_all_regions_live( - self.elements, - self.typeck, - kind, - live_at, - &self.inflowing_loans, - ); - + Self::make_all_regions_live(self.elements, self.typeck, kind, live_at); polonius::add_drop_of_var_derefs_origin(self.typeck, dropped_local, &kind); } } @@ -592,7 +574,6 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> { typeck: &mut TypeChecker<'_, 'tcx>, value: impl TypeVisitable<TyCtxt<'tcx>>, live_at: &IntervalSet<PointIndex>, - inflowing_loans: &SparseBitMatrix<RegionVid, BorrowIndex>, ) { debug!("make_all_regions_live(value={:?})", value); debug!( @@ -600,12 +581,6 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> { values::pretty_print_points(elements, live_at.iter()), ); - // When using `-Zpolonius=next`, we want to record the loans that flow into this value's - // regions as being live at the given `live_at` points: this will be used to compute the - // location where a loan goes out of scope. - let num_loans = typeck.borrowck_context.borrow_set.len(); - let value_loans = &mut HybridBitSet::new_empty(num_loans); - value.visit_with(&mut for_liveness::FreeRegionsVisitor { tcx: typeck.tcx(), param_env: typeck.param_env, @@ -617,21 +592,8 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> { .constraints .liveness_constraints .add_points(live_region_vid, live_at); - - // There can only be inflowing loans for this region when we are using - // `-Zpolonius=next`. - if let Some(inflowing) = inflowing_loans.row(live_region_vid) { - value_loans.union(inflowing); - } }, }); - - // Record the loans reaching the value. - if !value_loans.is_empty() { - for point in live_at.iter() { - typeck.borrowck_context.live_loans.union_row(point, value_loans); - } - } } fn compute_drop_data( diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs index d4fd1a3cf2a..074d0db6bf8 100644 --- a/compiler/rustc_borrowck/src/type_check/mod.rs +++ b/compiler/rustc_borrowck/src/type_check/mod.rs @@ -14,7 +14,6 @@ use rustc_hir as hir; use rustc_hir::def::DefKind; use rustc_hir::def_id::LocalDefId; use rustc_hir::lang_items::LangItem; -use rustc_index::bit_set::SparseBitMatrix; use rustc_index::{IndexSlice, IndexVec}; use rustc_infer::infer::canonical::QueryRegionConstraints; use rustc_infer::infer::outlives::env::RegionBoundPairs; @@ -51,8 +50,6 @@ use rustc_mir_dataflow::impls::MaybeInitializedPlaces; use rustc_mir_dataflow::move_paths::MoveData; use rustc_mir_dataflow::ResultsCursor; -use crate::dataflow::BorrowIndex; -use crate::region_infer::values::PointIndex; use crate::session_diagnostics::{MoveUnsized, SimdShuffleLastConst}; use crate::{ borrow_set::BorrowSet, @@ -166,9 +163,6 @@ pub(crate) fn type_check<'mir, 'tcx>( debug!(?normalized_inputs_and_output); - // When using `-Zpolonius=next`, liveness will record the set of live loans per point. - let mut live_loans = SparseBitMatrix::new(borrow_set.len()); - let mut borrowck_context = BorrowCheckContext { universal_regions, location_table, @@ -176,7 +170,6 @@ pub(crate) fn type_check<'mir, 'tcx>( all_facts, constraints: &mut constraints, upvars, - live_loans: &mut live_loans, }; let mut checker = TypeChecker::new( @@ -243,7 +236,7 @@ pub(crate) fn type_check<'mir, 'tcx>( }) .collect(); - MirTypeckResults { constraints, universal_region_relations, opaque_type_values, live_loans } + MirTypeckResults { constraints, universal_region_relations, opaque_type_values } } fn translate_outlives_facts(typeck: &mut TypeChecker<'_, '_>) { @@ -858,10 +851,6 @@ struct BorrowCheckContext<'a, 'tcx> { borrow_set: &'a BorrowSet<'tcx>, pub(crate) constraints: &'a mut MirTypeckRegionConstraints<'tcx>, upvars: &'a [&'a ty::CapturedPlace<'tcx>], - - /// The set of loans that are live at a given point in the CFG, filled in by `liveness::trace`, - /// when using `-Zpolonius=next`. - pub(crate) live_loans: &'a mut SparseBitMatrix<PointIndex, BorrowIndex>, } /// Holder struct for passing results from MIR typeck to the rest of the non-lexical regions @@ -870,9 +859,6 @@ pub(crate) struct MirTypeckResults<'tcx> { pub(crate) constraints: MirTypeckRegionConstraints<'tcx>, pub(crate) universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>, pub(crate) opaque_type_values: FxIndexMap<OpaqueTypeKey<'tcx>, OpaqueHiddenType<'tcx>>, - - /// The set of loans that are live at a given point in the CFG, when using `-Zpolonius=next`. - pub(crate) live_loans: SparseBitMatrix<PointIndex, BorrowIndex>, } /// A collection of region constraints that must be satisfied for the |