Split lifetimes on mir borrowck dataflow

Author: oli-obk

compiler/rustc_borrowck/src/dataflow.rs

@@ -15,24 +15,24 @@ use std::fmt;
 use crate::{places_conflict, BorrowSet, PlaceConflictBias, PlaceExt, RegionInferenceContext};
 
 /// The results of the dataflow analyses used by the borrow checker.
-pub struct BorrowckResults<'mir, 'tcx> {
-    pub(crate) borrows: Results<'tcx, Borrows<'mir, 'tcx>>,
-    pub(crate) uninits: Results<'tcx, MaybeUninitializedPlaces<'mir, 'tcx>>,
-    pub(crate) ever_inits: Results<'tcx, EverInitializedPlaces<'mir, 'tcx>>,
+pub struct BorrowckResults<'a, 'mir, 'tcx> {
+    pub(crate) borrows: Results<'tcx, Borrows<'a, 'mir, 'tcx>>,
+    pub(crate) uninits: Results<'tcx, MaybeUninitializedPlaces<'a, 'mir, 'tcx>>,
+    pub(crate) ever_inits: Results<'tcx, EverInitializedPlaces<'a, 'mir, 'tcx>>,
 }
 
 /// The transient state of the dataflow analyses used by the borrow checker.
 #[derive(Debug)]
-pub struct BorrowckFlowState<'mir, 'tcx> {
-    pub(crate) borrows: <Borrows<'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
-    pub(crate) uninits: <MaybeUninitializedPlaces<'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
-    pub(crate) ever_inits: <EverInitializedPlaces<'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
+pub struct BorrowckFlowState<'a, 'mir, 'tcx> {
+    pub(crate) borrows: <Borrows<'a, 'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
+    pub(crate) uninits: <MaybeUninitializedPlaces<'a, 'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
+    pub(crate) ever_inits: <EverInitializedPlaces<'a, 'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
 }
 
-impl<'mir, 'tcx> ResultsVisitable<'tcx> for BorrowckResults<'mir, 'tcx> {
+impl<'a, 'mir, 'tcx> ResultsVisitable<'tcx> for BorrowckResults<'a, 'mir, 'tcx> {
     // All three analyses are forward, but we have to use just one here.
-    type Direction = <Borrows<'mir, 'tcx> as AnalysisDomain<'tcx>>::Direction;
-    type FlowState = BorrowckFlowState<'mir, 'tcx>;
+    type Direction = <Borrows<'a, 'mir, 'tcx> as AnalysisDomain<'tcx>>::Direction;
+    type FlowState = BorrowckFlowState<'a, 'mir, 'tcx>;
 
     fn new_flow_state(&self, body: &mir::Body<'tcx>) -> Self::FlowState {
         BorrowckFlowState {
@@ -106,11 +106,11 @@ rustc_index::newtype_index! {
 /// `BorrowIndex`, and maps each such index to a `BorrowData`
 /// describing the borrow. These indexes are used for representing the
 /// borrows in compact bitvectors.
-pub struct Borrows<'mir, 'tcx> {
+pub struct Borrows<'a, 'mir, 'tcx> {
     tcx: TyCtxt<'tcx>,
     body: &'mir Body<'tcx>,
 
-    borrow_set: &'mir BorrowSet<'tcx>,
+    borrow_set: &'a BorrowSet<'tcx>,
     borrows_out_of_scope_at_location: FxIndexMap<Location, Vec<BorrowIndex>>,
 }
 
@@ -389,12 +389,12 @@ impl<'tcx> PoloniusOutOfScopePrecomputer<'_, 'tcx> {
     }
 }
 
-impl<'mir, 'tcx> Borrows<'mir, 'tcx> {
+impl<'a, 'mir, 'tcx> Borrows<'a, 'mir, 'tcx> {
     pub fn new(
         tcx: TyCtxt<'tcx>,
         body: &'mir Body<'tcx>,
-        regioncx: &'mir RegionInferenceContext<'tcx>,
-        borrow_set: &'mir BorrowSet<'tcx>,
+        regioncx: &RegionInferenceContext<'tcx>,
+        borrow_set: &'a BorrowSet<'tcx>,
     ) -> Self {
         let mut borrows_out_of_scope_at_location =
             calculate_borrows_out_of_scope_at_location(body, regioncx, borrow_set);
@@ -494,7 +494,7 @@ impl<'mir, 'tcx> Borrows<'mir, 'tcx> {
     }
 }
 
-impl<'tcx> rustc_mir_dataflow::AnalysisDomain<'tcx> for Borrows<'_, 'tcx> {
+impl<'tcx> rustc_mir_dataflow::AnalysisDomain<'tcx> for Borrows<'_, '_, 'tcx> {
     type Domain = BitSet<BorrowIndex>;
 
     const NAME: &'static str = "borrows";
@@ -517,7 +517,7 @@ impl<'tcx> rustc_mir_dataflow::AnalysisDomain<'tcx> for Borrows<'_, 'tcx> {
 ///   region stops containing the CFG points reachable from the issuing location.
 /// - we also kill loans of conflicting places when overwriting a shared path: e.g. borrows of
 ///   `a.b.c` when `a` is overwritten.
-impl<'tcx> rustc_mir_dataflow::GenKillAnalysis<'tcx> for Borrows<'_, 'tcx> {
+impl<'tcx> rustc_mir_dataflow::GenKillAnalysis<'tcx> for Borrows<'_, '_, 'tcx> {
     type Idx = BorrowIndex;
 
     fn domain_size(&self, _: &mir::Body<'tcx>) -> usize {
@@ -617,8 +617,8 @@ impl<'tcx> rustc_mir_dataflow::GenKillAnalysis<'tcx> for Borrows<'_, 'tcx> {
     }
 }
 
-impl DebugWithContext<Borrows<'_, '_>> for BorrowIndex {
-    fn fmt_with(&self, ctxt: &Borrows<'_, '_>, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+impl DebugWithContext<Borrows<'_, '_, '_>> for BorrowIndex {
+    fn fmt_with(&self, ctxt: &Borrows<'_, '_, '_>, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{:?}", ctxt.location(*self))
     }
 }

compiler/rustc_borrowck/src/lib.rs

@@ -605,15 +605,15 @@ struct MirBorrowckCtxt<'a, 'mir, 'cx, 'tcx> {
 // 2. loans made in overlapping scopes do not conflict
 // 3. assignments do not affect things loaned out as immutable
 // 4. moves do not affect things loaned out in any way
-impl<'mir, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'mir, 'tcx, R>
-    for MirBorrowckCtxt<'_, 'mir, '_, 'tcx>
+impl<'a, 'mir, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'mir, 'tcx, R>
+    for MirBorrowckCtxt<'a, 'mir, '_, 'tcx>
 {
-    type FlowState = Flows<'mir, 'tcx>;
+    type FlowState = Flows<'a, 'mir, 'tcx>;
 
     fn visit_statement_before_primary_effect(
         &mut self,
         _results: &mut R,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
         stmt: &'mir Statement<'tcx>,
         location: Location,
     ) {
@@ -683,7 +683,7 @@ impl<'mir, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'mir, 'tcx, R>
     fn visit_terminator_before_primary_effect(
         &mut self,
         _results: &mut R,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
         term: &'mir Terminator<'tcx>,
         loc: Location,
     ) {
@@ -794,7 +794,7 @@ impl<'mir, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'mir, 'tcx, R>
     fn visit_terminator_after_primary_effect(
         &mut self,
         _results: &mut R,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
         term: &'mir Terminator<'tcx>,
         loc: Location,
     ) {
@@ -988,7 +988,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         place_span: (Place<'tcx>, Span),
         kind: (AccessDepth, ReadOrWrite),
         is_local_mutation_allowed: LocalMutationIsAllowed,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         let (sd, rw) = kind;
 
@@ -1038,7 +1038,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         place_span: (Place<'tcx>, Span),
         sd: AccessDepth,
         rw: ReadOrWrite,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) -> bool {
         let mut error_reported = false;
         let borrow_set = Rc::clone(&self.borrow_set);
@@ -1179,7 +1179,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         location: Location,
         place_span: (Place<'tcx>, Span),
         kind: AccessDepth,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         // Write of P[i] or *P requires P init'd.
         self.check_if_assigned_path_is_moved(location, place_span, flow_state);
@@ -1197,7 +1197,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         &mut self,
         location: Location,
         (rvalue, span): (&'mir Rvalue<'tcx>, Span),
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         match rvalue {
             &Rvalue::Ref(_ /*rgn*/, bk, place) => {
@@ -1455,7 +1455,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         &mut self,
         location: Location,
         (operand, span): (&'mir Operand<'tcx>, Span),
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         match *operand {
             Operand::Copy(place) => {
@@ -1579,7 +1579,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         &mut self,
         location: Location,
         span: Span,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         // Two-phase borrow support: For each activation that is newly
         // generated at this statement, check if it interferes with
@@ -1743,7 +1743,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         location: Location,
         desired_action: InitializationRequiringAction,
         place_span: (PlaceRef<'tcx>, Span),
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         let maybe_uninits = &flow_state.uninits;
 
@@ -1848,7 +1848,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         location: Location,
         desired_action: InitializationRequiringAction,
         place_span: (PlaceRef<'tcx>, Span),
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         let maybe_uninits = &flow_state.uninits;
 
@@ -1947,7 +1947,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         &mut self,
         location: Location,
         (place, span): (Place<'tcx>, Span),
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         debug!("check_if_assigned_path_is_moved place: {:?}", place);
 
@@ -2013,7 +2013,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
             location: Location,
             base: PlaceRef<'tcx>,
             span: Span,
-            flow_state: &Flows<'mir, 'tcx>,
+            flow_state: &Flows<'_, 'mir, 'tcx>,
         ) {
             // rust-lang/rust#21232: Until Rust allows reads from the
             // initialized parts of partially initialized structs, we
@@ -2104,7 +2104,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         (place, span): (Place<'tcx>, Span),
         kind: ReadOrWrite,
         is_local_mutation_allowed: LocalMutationIsAllowed,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
         location: Location,
     ) -> bool {
         debug!(
@@ -2220,15 +2220,15 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
     fn is_local_ever_initialized(
         &self,
         local: Local,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) -> Option<InitIndex> {
         let mpi = self.move_data.rev_lookup.find_local(local)?;
         let ii = &self.move_data.init_path_map[mpi];
         ii.into_iter().find(|&&index| flow_state.ever_inits.contains(index)).copied()
     }
 
     /// Adds the place into the used mutable variables set
-    fn add_used_mut(&mut self, root_place: RootPlace<'tcx>, flow_state: &Flows<'mir, 'tcx>) {
+    fn add_used_mut(&mut self, root_place: RootPlace<'tcx>, flow_state: &Flows<'_, 'mir, 'tcx>) {
         match root_place {
             RootPlace { place_local: local, place_projection: [], is_local_mutation_allowed } => {
                 // If the local may have been initialized, and it is now currently being

compiler/rustc_borrowck/src/nll.rs

@@ -81,7 +81,7 @@ pub(crate) fn compute_regions<'cx, 'tcx>(
     promoted: &IndexSlice<Promoted, Body<'tcx>>,
     location_table: &LocationTable,
     param_env: ty::ParamEnv<'tcx>,
-    flow_inits: &mut ResultsCursor<'cx, 'tcx, MaybeInitializedPlaces<'cx, 'tcx>>,
+    flow_inits: &mut ResultsCursor<'cx, 'tcx, MaybeInitializedPlaces<'_, 'cx, 'tcx>>,
     move_data: &MoveData<'tcx>,
     borrow_set: &BorrowSet<'tcx>,
     upvars: &[&ty::CapturedPlace<'tcx>],

compiler/rustc_borrowck/src/type_check/liveness/mod.rs

@@ -34,7 +34,7 @@ pub(super) fn generate<'mir, 'tcx>(
     typeck: &mut TypeChecker<'_, 'tcx>,
     body: &Body<'tcx>,
     elements: &Rc<DenseLocationMap>,
-    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
+    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'_, 'mir, 'tcx>>,
     move_data: &MoveData<'tcx>,
 ) {
     debug!("liveness::generate");

compiler/rustc_borrowck/src/type_check/liveness/trace.rs

@@ -43,7 +43,7 @@ pub(super) fn trace<'mir, 'tcx>(
     typeck: &mut TypeChecker<'_, 'tcx>,
     body: &Body<'tcx>,
     elements: &Rc<DenseLocationMap>,
-    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
+    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'_, 'mir, 'tcx>>,
     move_data: &MoveData<'tcx>,
     relevant_live_locals: Vec<Local>,
     boring_locals: Vec<Local>,
@@ -101,7 +101,7 @@ pub(super) fn trace<'mir, 'tcx>(
 }
 
 /// Contextual state for the type-liveness coroutine.
-struct LivenessContext<'me, 'typeck, 'flow, 'tcx> {
+struct LivenessContext<'a, 'me, 'typeck, 'flow, 'tcx> {
     /// Current type-checker, giving us our inference context etc.
     typeck: &'me mut TypeChecker<'typeck, 'tcx>,
 
@@ -119,7 +119,7 @@ struct LivenessContext<'me, 'typeck, 'flow, 'tcx> {
 
     /// Results of dataflow tracking which variables (and paths) have been
     /// initialized.
-    flow_inits: &'me mut ResultsCursor<'flow, 'tcx, MaybeInitializedPlaces<'flow, 'tcx>>,
+    flow_inits: &'me mut ResultsCursor<'flow, 'tcx, MaybeInitializedPlaces<'a, 'flow, 'tcx>>,
 
     /// Index indicating where each variable is assigned, used, or
     /// dropped.
@@ -131,8 +131,8 @@ struct DropData<'tcx> {
     region_constraint_data: Option<&'tcx QueryRegionConstraints<'tcx>>,
 }
 
-struct LivenessResults<'me, 'typeck, 'flow, 'tcx> {
-    cx: LivenessContext<'me, 'typeck, 'flow, 'tcx>,
+struct LivenessResults<'a, 'me, 'typeck, 'flow, 'tcx> {
+    cx: LivenessContext<'a, 'me, 'typeck, 'flow, 'tcx>,
 
     /// Set of points that define the current local.
     defs: BitSet<PointIndex>,
@@ -153,8 +153,8 @@ struct LivenessResults<'me, 'typeck, 'flow, 'tcx> {
     stack: Vec<PointIndex>,
 }
 
-impl<'me, 'typeck, 'flow, 'tcx> LivenessResults<'me, 'typeck, 'flow, 'tcx> {
-    fn new(cx: LivenessContext<'me, 'typeck, 'flow, 'tcx>) -> Self {
+impl<'a, 'me, 'typeck, 'flow, 'tcx> LivenessResults<'a, 'me, 'typeck, 'flow, 'tcx> {
+    fn new(cx: LivenessContext<'a, 'me, 'typeck, 'flow, 'tcx>) -> Self {
         let num_points = cx.elements.num_points();
         LivenessResults {
             cx,
@@ -507,7 +507,7 @@ impl<'me, 'typeck, 'flow, 'tcx> LivenessResults<'me, 'typeck, 'flow, 'tcx> {
     }
 }
 
-impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
+impl<'tcx> LivenessContext<'_, '_, '_, '_, 'tcx> {
     /// Returns `true` if the local variable (or some part of it) is initialized at the current
     /// cursor position. Callers should call one of the `seek` methods immediately before to point
     /// the cursor to the desired location.

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -129,7 +129,7 @@ pub(crate) fn type_check<'mir, 'tcx>(
     location_table: &LocationTable,
     borrow_set: &BorrowSet<'tcx>,
     all_facts: &mut Option<AllFacts>,
-    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
+    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'_, 'mir, 'tcx>>,
     move_data: &MoveData<'tcx>,
     elements: &Rc<DenseLocationMap>,
     upvars: &[&ty::CapturedPlace<'tcx>],