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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-06-19 09:26:03 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-06-19 09:26:03 +0000 |
commit | 9918693037dce8aa4bb6f08741b6812923486c18 (patch) | |
tree | 21d2b40bec7e6a7ea664acee056eb3d08e15a1cf /compiler/rustc_borrowck/src/constraint_generation.rs | |
parent | Releasing progress-linux version 1.75.0+dfsg1-5~progress7.99u1. (diff) | |
download | rustc-9918693037dce8aa4bb6f08741b6812923486c18.tar.xz rustc-9918693037dce8aa4bb6f08741b6812923486c18.zip |
Merging upstream version 1.76.0+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'compiler/rustc_borrowck/src/constraint_generation.rs')
-rw-r--r-- | compiler/rustc_borrowck/src/constraint_generation.rs | 248 |
1 files changed, 0 insertions, 248 deletions
diff --git a/compiler/rustc_borrowck/src/constraint_generation.rs b/compiler/rustc_borrowck/src/constraint_generation.rs deleted file mode 100644 index 1f642099f..000000000 --- a/compiler/rustc_borrowck/src/constraint_generation.rs +++ /dev/null @@ -1,248 +0,0 @@ -#![deny(rustc::untranslatable_diagnostic)] -#![deny(rustc::diagnostic_outside_of_impl)] -use rustc_infer::infer::InferCtxt; -use rustc_middle::mir::visit::TyContext; -use rustc_middle::mir::visit::Visitor; -use rustc_middle::mir::{ - Body, Local, Location, Place, PlaceRef, ProjectionElem, Rvalue, SourceInfo, Statement, - StatementKind, Terminator, TerminatorKind, UserTypeProjection, -}; -use rustc_middle::ty::visit::TypeVisitable; -use rustc_middle::ty::GenericArgsRef; -use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt}; - -use crate::{ - borrow_set::BorrowSet, facts::AllFacts, location::LocationTable, places_conflict, - region_infer::values::LivenessValues, -}; - -pub(super) fn generate_constraints<'tcx>( - infcx: &InferCtxt<'tcx>, - liveness_constraints: &mut LivenessValues<RegionVid>, - all_facts: &mut Option<AllFacts>, - location_table: &LocationTable, - body: &Body<'tcx>, - borrow_set: &BorrowSet<'tcx>, -) { - let mut cg = ConstraintGeneration { - borrow_set, - infcx, - liveness_constraints, - location_table, - all_facts, - body, - }; - - for (bb, data) in body.basic_blocks.iter_enumerated() { - cg.visit_basic_block_data(bb, data); - } -} - -/// 'cg = the duration of the constraint generation process itself. -struct ConstraintGeneration<'cg, 'tcx> { - infcx: &'cg InferCtxt<'tcx>, - all_facts: &'cg mut Option<AllFacts>, - location_table: &'cg LocationTable, - liveness_constraints: &'cg mut LivenessValues<RegionVid>, - borrow_set: &'cg BorrowSet<'tcx>, - body: &'cg Body<'tcx>, -} - -impl<'cg, 'tcx> Visitor<'tcx> for ConstraintGeneration<'cg, 'tcx> { - /// We sometimes have `args` within an rvalue, or within a - /// call. Make them live at the location where they appear. - fn visit_args(&mut self, args: &GenericArgsRef<'tcx>, location: Location) { - self.add_regular_live_constraint(*args, location); - self.super_args(args); - } - - /// We sometimes have `region` within an rvalue, or within a - /// call. Make them live at the location where they appear. - fn visit_region(&mut self, region: ty::Region<'tcx>, location: Location) { - self.add_regular_live_constraint(region, location); - self.super_region(region); - } - - /// We sometimes have `ty` within an rvalue, or within a - /// call. Make them live at the location where they appear. - fn visit_ty(&mut self, ty: Ty<'tcx>, ty_context: TyContext) { - match ty_context { - TyContext::ReturnTy(SourceInfo { span, .. }) - | TyContext::YieldTy(SourceInfo { span, .. }) - | TyContext::UserTy(span) - | TyContext::LocalDecl { source_info: SourceInfo { span, .. }, .. } => { - span_bug!(span, "should not be visiting outside of the CFG: {:?}", ty_context); - } - TyContext::Location(location) => { - self.add_regular_live_constraint(ty, location); - } - } - - self.super_ty(ty); - } - - fn visit_statement(&mut self, statement: &Statement<'tcx>, location: Location) { - if let Some(all_facts) = self.all_facts { - let _prof_timer = self.infcx.tcx.prof.generic_activity("polonius_fact_generation"); - all_facts.cfg_edge.push(( - self.location_table.start_index(location), - self.location_table.mid_index(location), - )); - - all_facts.cfg_edge.push(( - self.location_table.mid_index(location), - self.location_table.start_index(location.successor_within_block()), - )); - - // If there are borrows on this now dead local, we need to record them as `killed`. - if let StatementKind::StorageDead(local) = statement.kind { - record_killed_borrows_for_local( - all_facts, - self.borrow_set, - self.location_table, - local, - location, - ); - } - } - - self.super_statement(statement, location); - } - - fn visit_assign(&mut self, place: &Place<'tcx>, rvalue: &Rvalue<'tcx>, location: Location) { - // When we see `X = ...`, then kill borrows of - // `(*X).foo` and so forth. - self.record_killed_borrows_for_place(*place, location); - - self.super_assign(place, rvalue, location); - } - - fn visit_terminator(&mut self, terminator: &Terminator<'tcx>, location: Location) { - if let Some(all_facts) = self.all_facts { - let _prof_timer = self.infcx.tcx.prof.generic_activity("polonius_fact_generation"); - all_facts.cfg_edge.push(( - self.location_table.start_index(location), - self.location_table.mid_index(location), - )); - - let successor_blocks = terminator.successors(); - all_facts.cfg_edge.reserve(successor_blocks.size_hint().0); - for successor_block in successor_blocks { - all_facts.cfg_edge.push(( - self.location_table.mid_index(location), - self.location_table.start_index(successor_block.start_location()), - )); - } - } - - // A `Call` terminator's return value can be a local which has borrows, - // so we need to record those as `killed` as well. - if let TerminatorKind::Call { destination, .. } = terminator.kind { - self.record_killed_borrows_for_place(destination, location); - } - - self.super_terminator(terminator, location); - } - - fn visit_ascribe_user_ty( - &mut self, - _place: &Place<'tcx>, - _variance: ty::Variance, - _user_ty: &UserTypeProjection, - _location: Location, - ) { - } -} - -impl<'cx, 'tcx> ConstraintGeneration<'cx, 'tcx> { - /// Some variable with type `live_ty` is "regular live" at - /// `location` -- i.e., it may be used later. This means that all - /// regions appearing in the type `live_ty` must be live at - /// `location`. - fn add_regular_live_constraint<T>(&mut self, live_ty: T, location: Location) - where - T: TypeVisitable<TyCtxt<'tcx>>, - { - debug!("add_regular_live_constraint(live_ty={:?}, location={:?})", live_ty, location); - - self.infcx.tcx.for_each_free_region(&live_ty, |live_region| { - let vid = live_region.as_var(); - self.liveness_constraints.add_element(vid, location); - }); - } - - /// When recording facts for Polonius, records the borrows on the specified place - /// as `killed`. For example, when assigning to a local, or on a call's return destination. - fn record_killed_borrows_for_place(&mut self, place: Place<'tcx>, location: Location) { - if let Some(all_facts) = self.all_facts { - let _prof_timer = self.infcx.tcx.prof.generic_activity("polonius_fact_generation"); - - // Depending on the `Place` we're killing: - // - if it's a local, or a single deref of a local, - // we kill all the borrows on the local. - // - if it's a deeper projection, we have to filter which - // of the borrows are killed: the ones whose `borrowed_place` - // conflicts with the `place`. - match place.as_ref() { - PlaceRef { local, projection: &[] } - | PlaceRef { local, projection: &[ProjectionElem::Deref] } => { - debug!( - "Recording `killed` facts for borrows of local={:?} at location={:?}", - local, location - ); - - record_killed_borrows_for_local( - all_facts, - self.borrow_set, - self.location_table, - local, - location, - ); - } - - PlaceRef { local, projection: &[.., _] } => { - // Kill conflicting borrows of the innermost local. - debug!( - "Recording `killed` facts for borrows of \ - innermost projected local={:?} at location={:?}", - local, location - ); - - if let Some(borrow_indices) = self.borrow_set.local_map.get(&local) { - for &borrow_index in borrow_indices { - let places_conflict = places_conflict::places_conflict( - self.infcx.tcx, - self.body, - self.borrow_set[borrow_index].borrowed_place, - place, - places_conflict::PlaceConflictBias::NoOverlap, - ); - - if places_conflict { - let location_index = self.location_table.mid_index(location); - all_facts.loan_killed_at.push((borrow_index, location_index)); - } - } - } - } - } - } - } -} - -/// When recording facts for Polonius, records the borrows on the specified local as `killed`. -fn record_killed_borrows_for_local( - all_facts: &mut AllFacts, - borrow_set: &BorrowSet<'_>, - location_table: &LocationTable, - local: Local, - location: Location, -) { - if let Some(borrow_indices) = borrow_set.local_map.get(&local) { - all_facts.loan_killed_at.reserve(borrow_indices.len()); - for &borrow_index in borrow_indices { - let location_index = location_table.mid_index(location); - all_facts.loan_killed_at.push((borrow_index, location_index)); - } - } -} |