Auto merge of rust-lang#120068 - matthiaskrgr:rollup-vxugut5, r=matthiaskrgr

Rollup of 10 pull requests

Successful merges:

 - rust-lang#115291 (Save liveness results for DestinationPropagation)
 - rust-lang#119855 (Enable Static Builds for FreeBSD)
 - rust-lang#119975 (Don't ICE if TAIT-defining fn contains a closure with `_` in return type)
 - rust-lang#120001 (Consistently unset RUSTC_BOOTSTRAP when compiling bootstrap)
 - rust-lang#120020 (Gracefully handle missing typeck information if typeck errored)
 - rust-lang#120031 (Construct closure type eagerly)
 - rust-lang#120032 (Fix `rustc_abi` build on stable)
 - rust-lang#120039 (pat_analysis: Don't rely on contiguous `VariantId`s outside of rustc)
 - rust-lang#120044 (Fix typo in comments (in_place_collect))
 - rust-lang#120056 (Use FnOnceOutput instead of FnOnce where expected)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

Diff for: Cargo.lock

@@ -4355,6 +4355,7 @@ name = "rustc_pattern_analysis"
 version = "0.0.0"
 dependencies = [
  "derivative",
+ "rustc-hash",
  "rustc_apfloat",
  "rustc_arena",
  "rustc_data_structures",

Diff for: compiler/rustc_abi/src/lib.rs

@@ -49,7 +49,14 @@ bitflags! {
                                  | ReprFlags::IS_LINEAR.bits();
     }
 }
-rustc_data_structures::external_bitflags_debug! { ReprFlags }
+
+// This is the same as `rustc_data_structures::external_bitflags_debug` but without the
+// `rustc_data_structures` to make it build on stable.
+impl std::fmt::Debug for ReprFlags {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        bitflags::parser::to_writer(self, f)
+    }
+}
 
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
 #[cfg_attr(feature = "nightly", derive(Encodable_Generic, Decodable_Generic, HashStable_Generic))]

Diff for: compiler/rustc_borrowck/src/nll.rs

@@ -12,6 +12,7 @@ use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{self, OpaqueHiddenType, TyCtxt};
 use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
 use rustc_mir_dataflow::move_paths::MoveData;
+use rustc_mir_dataflow::points::DenseLocationMap;
 use rustc_mir_dataflow::ResultsCursor;
 use rustc_span::symbol::sym;
 use std::env;
@@ -27,7 +28,7 @@ use crate::{
     facts::{AllFacts, AllFactsExt, RustcFacts},
     location::LocationTable,
     polonius,
-    region_infer::{values::RegionValueElements, RegionInferenceContext},
+    region_infer::RegionInferenceContext,
     renumber,
     type_check::{self, MirTypeckRegionConstraints, MirTypeckResults},
     universal_regions::UniversalRegions,
@@ -98,7 +99,7 @@ pub(crate) fn compute_regions<'cx, 'tcx>(
 
     let universal_regions = Rc::new(universal_regions);
 
-    let elements = &Rc::new(RegionValueElements::new(body));
+    let elements = &Rc::new(DenseLocationMap::new(body));
 
     // Run the MIR type-checker.
     let MirTypeckResults { constraints, universal_region_relations, opaque_type_values } =

Diff for: compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -19,6 +19,7 @@ use rustc_middle::mir::{
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::traits::ObligationCauseCode;
 use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitableExt};
+use rustc_mir_dataflow::points::DenseLocationMap;
 use rustc_span::Span;
 
 use crate::constraints::graph::{self, NormalConstraintGraph, RegionGraph};
@@ -30,8 +31,7 @@ use crate::{
     nll::PoloniusOutput,
     region_infer::reverse_sccs::ReverseSccGraph,
     region_infer::values::{
-        LivenessValues, PlaceholderIndices, RegionElement, RegionValueElements, RegionValues,
-        ToElementIndex,
+        LivenessValues, PlaceholderIndices, RegionElement, RegionValues, ToElementIndex,
     },
     type_check::{free_region_relations::UniversalRegionRelations, Locations},
     universal_regions::UniversalRegions,
@@ -330,7 +330,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         universe_causes: FxIndexMap<ty::UniverseIndex, UniverseInfo<'tcx>>,
         type_tests: Vec<TypeTest<'tcx>>,
         liveness_constraints: LivenessValues,
-        elements: &Rc<RegionValueElements>,
+        elements: &Rc<DenseLocationMap>,
     ) -> Self {
         debug!("universal_regions: {:#?}", universal_regions);
         debug!("outlives constraints: {:#?}", outlives_constraints);

Diff for: compiler/rustc_borrowck/src/region_infer/values.rs

@@ -5,97 +5,13 @@ use rustc_index::bit_set::SparseBitMatrix;
 use rustc_index::interval::IntervalSet;
 use rustc_index::interval::SparseIntervalMatrix;
 use rustc_index::Idx;
-use rustc_index::IndexVec;
-use rustc_middle::mir::{BasicBlock, Body, Location};
+use rustc_middle::mir::{BasicBlock, Location};
 use rustc_middle::ty::{self, RegionVid};
+use rustc_mir_dataflow::points::{DenseLocationMap, PointIndex};
 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?
-    statements_before_block: IndexVec<BasicBlock, usize>,
-
-    /// Map backward from each point to the basic block that it
-    /// belongs to.
-    basic_blocks: IndexVec<PointIndex, BasicBlock>,
-
-    num_points: usize,
-}
-
-impl RegionValueElements {
-    pub(crate) fn new(body: &Body<'_>) -> Self {
-        let mut num_points = 0;
-        let statements_before_block: IndexVec<BasicBlock, usize> = body
-            .basic_blocks
-            .iter()
-            .map(|block_data| {
-                let v = num_points;
-                num_points += block_data.statements.len() + 1;
-                v
-            })
-            .collect();
-        debug!("RegionValueElements: statements_before_block={:#?}", statements_before_block);
-        debug!("RegionValueElements: num_points={:#?}", num_points);
-
-        let mut basic_blocks = IndexVec::with_capacity(num_points);
-        for (bb, bb_data) in body.basic_blocks.iter_enumerated() {
-            basic_blocks.extend((0..=bb_data.statements.len()).map(|_| bb));
-        }
-
-        Self { statements_before_block, basic_blocks, num_points }
-    }
-
-    /// Total number of point indices
-    pub(crate) fn num_points(&self) -> usize {
-        self.num_points
-    }
-
-    /// Converts a `Location` into a `PointIndex`. O(1).
-    pub(crate) fn point_from_location(&self, location: Location) -> PointIndex {
-        let Location { block, statement_index } = location;
-        let start_index = self.statements_before_block[block];
-        PointIndex::new(start_index + statement_index)
-    }
-
-    /// Converts a `Location` into a `PointIndex`. O(1).
-    pub(crate) fn entry_point(&self, block: BasicBlock) -> PointIndex {
-        let start_index = self.statements_before_block[block];
-        PointIndex::new(start_index)
-    }
-
-    /// Return the PointIndex for the block start of this index.
-    pub(crate) fn to_block_start(&self, index: PointIndex) -> PointIndex {
-        PointIndex::new(self.statements_before_block[self.basic_blocks[index]])
-    }
-
-    /// Converts a `PointIndex` back to a location. O(1).
-    pub(crate) fn to_location(&self, index: PointIndex) -> Location {
-        assert!(index.index() < self.num_points);
-        let block = self.basic_blocks[index];
-        let start_index = self.statements_before_block[block];
-        let statement_index = index.index() - start_index;
-        Location { block, statement_index }
-    }
-
-    /// Sometimes we get point-indices back from bitsets that may be
-    /// out of range (because they round up to the nearest 2^N number
-    /// of bits). Use this function to filter such points out if you
-    /// like.
-    pub(crate) fn point_in_range(&self, index: PointIndex) -> bool {
-        index.index() < self.num_points
-    }
-}
-
-rustc_index::newtype_index! {
-    /// A single integer representing a `Location` in the MIR control-flow
-    /// graph. Constructed efficiently from `RegionValueElements`.
-    #[orderable]
-    #[debug_format = "PointIndex({})"]
-    pub struct PointIndex {}
-}
+use crate::BorrowIndex;
 
 rustc_index::newtype_index! {
     /// A single integer representing a `ty::Placeholder`.
@@ -123,7 +39,7 @@ pub(crate) enum RegionElement {
 /// an interval matrix storing liveness ranges for each region-vid.
 pub(crate) struct LivenessValues {
     /// The map from locations to points.
-    elements: Rc<RegionValueElements>,
+    elements: Rc<DenseLocationMap>,
 
     /// For each region: the points where it is live.
     points: SparseIntervalMatrix<RegionVid, PointIndex>,
@@ -155,9 +71,9 @@ impl LiveLoans {
 
 impl LivenessValues {
     /// Create an empty map of regions to locations where they're live.
-    pub(crate) fn new(elements: Rc<RegionValueElements>) -> Self {
+    pub(crate) fn new(elements: Rc<DenseLocationMap>) -> Self {
         LivenessValues {
-            points: SparseIntervalMatrix::new(elements.num_points),
+            points: SparseIntervalMatrix::new(elements.num_points()),
             elements,
             loans: None,
         }
@@ -298,7 +214,7 @@ impl PlaceholderIndices {
 /// it would also contain various points from within the function.
 #[derive(Clone)]
 pub(crate) struct RegionValues<N: Idx> {
-    elements: Rc<RegionValueElements>,
+    elements: Rc<DenseLocationMap>,
     placeholder_indices: Rc<PlaceholderIndices>,
     points: SparseIntervalMatrix<N, PointIndex>,
     free_regions: SparseBitMatrix<N, RegionVid>,
@@ -313,14 +229,14 @@ impl<N: Idx> RegionValues<N> {
     /// Each of the regions in num_region_variables will be initialized with an
     /// empty set of points and no causal information.
     pub(crate) fn new(
-        elements: &Rc<RegionValueElements>,
+        elements: &Rc<DenseLocationMap>,
         num_universal_regions: usize,
         placeholder_indices: &Rc<PlaceholderIndices>,
     ) -> Self {
         let num_placeholders = placeholder_indices.len();
         Self {
             elements: elements.clone(),
-            points: SparseIntervalMatrix::new(elements.num_points),
+            points: SparseIntervalMatrix::new(elements.num_points()),
             placeholder_indices: placeholder_indices.clone(),
             free_regions: SparseBitMatrix::new(num_universal_regions),
             placeholders: SparseBitMatrix::new(num_placeholders),
@@ -486,7 +402,7 @@ impl ToElementIndex for ty::PlaceholderRegion {
 
 /// For debugging purposes, returns a pretty-printed string of the given points.
 pub(crate) fn pretty_print_points(
-    elements: &RegionValueElements,
+    elements: &DenseLocationMap,
     points: impl IntoIterator<Item = PointIndex>,
 ) -> String {
     pretty_print_region_elements(

Diff for: compiler/rustc_borrowck/src/type_check/liveness/local_use_map.rs

@@ -2,9 +2,9 @@ use rustc_data_structures::vec_linked_list as vll;
 use rustc_index::IndexVec;
 use rustc_middle::mir::visit::{PlaceContext, Visitor};
 use rustc_middle::mir::{Body, Local, Location};
+use rustc_mir_dataflow::points::{DenseLocationMap, PointIndex};
 
 use crate::def_use::{self, DefUse};
-use crate::region_infer::values::{PointIndex, RegionValueElements};
 
 /// A map that cross references each local with the locations where it
 /// is defined (assigned), used, or dropped. Used during liveness
@@ -60,7 +60,7 @@ impl vll::LinkElem for Appearance {
 impl LocalUseMap {
     pub(crate) fn build(
         live_locals: &[Local],
-        elements: &RegionValueElements,
+        elements: &DenseLocationMap,
         body: &Body<'_>,
     ) -> Self {
         let nones = IndexVec::from_elem(None, &body.local_decls);
@@ -103,7 +103,7 @@ impl LocalUseMap {
 
 struct LocalUseMapBuild<'me> {
     local_use_map: &'me mut LocalUseMap,
-    elements: &'me RegionValueElements,
+    elements: &'me DenseLocationMap,
 
     // Vector used in `visit_local` to signal which `Local`s do we need
     // def/use/drop information on, constructed from `live_locals` (that
@@ -144,7 +144,7 @@ impl LocalUseMapBuild<'_> {
     }
 
     fn insert(
-        elements: &RegionValueElements,
+        elements: &DenseLocationMap,
         first_appearance: &mut Option<AppearanceIndex>,
         appearances: &mut IndexVec<AppearanceIndex, Appearance>,
         location: Location,

Diff for: compiler/rustc_borrowck/src/type_check/liveness/mod.rs

@@ -6,14 +6,15 @@ use rustc_middle::ty::visit::TypeVisitable;
 use rustc_middle::ty::{GenericArgsRef, Region, RegionVid, Ty, TyCtxt};
 use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
 use rustc_mir_dataflow::move_paths::MoveData;
+use rustc_mir_dataflow::points::DenseLocationMap;
 use rustc_mir_dataflow::ResultsCursor;
 use std::rc::Rc;
 
 use crate::{
     constraints::OutlivesConstraintSet,
     facts::{AllFacts, AllFactsExt},
     location::LocationTable,
-    region_infer::values::{LivenessValues, RegionValueElements},
+    region_infer::values::LivenessValues,
     universal_regions::UniversalRegions,
 };
 
@@ -34,7 +35,7 @@ mod trace;
 pub(super) fn generate<'mir, 'tcx>(
     typeck: &mut TypeChecker<'_, 'tcx>,
     body: &Body<'tcx>,
-    elements: &Rc<RegionValueElements>,
+    elements: &Rc<DenseLocationMap>,
     flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
     move_data: &MoveData<'tcx>,
     location_table: &LocationTable,

Diff for: compiler/rustc_borrowck/src/type_check/liveness/trace.rs

@@ -7,6 +7,7 @@ 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::{Ty, TyCtxt, TypeVisitable, TypeVisitableExt};
+use rustc_mir_dataflow::points::{DenseLocationMap, PointIndex};
 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};
@@ -17,7 +18,7 @@ use rustc_mir_dataflow::move_paths::{HasMoveData, MoveData, MovePathIndex};
 use rustc_mir_dataflow::ResultsCursor;
 
 use crate::{
-    region_infer::values::{self, LiveLoans, PointIndex, RegionValueElements},
+    region_infer::values::{self, LiveLoans},
     type_check::liveness::local_use_map::LocalUseMap,
     type_check::liveness::polonius,
     type_check::NormalizeLocation,
@@ -41,7 +42,7 @@ use crate::{
 pub(super) fn trace<'mir, 'tcx>(
     typeck: &mut TypeChecker<'_, 'tcx>,
     body: &Body<'tcx>,
-    elements: &Rc<RegionValueElements>,
+    elements: &Rc<DenseLocationMap>,
     flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
     move_data: &MoveData<'tcx>,
     relevant_live_locals: Vec<Local>,
@@ -105,7 +106,7 @@ struct LivenessContext<'me, 'typeck, 'flow, 'tcx> {
     typeck: &'me mut TypeChecker<'typeck, 'tcx>,
 
     /// Defines the `PointIndex` mapping
-    elements: &'me RegionValueElements,
+    elements: &'me DenseLocationMap,
 
     /// MIR we are analyzing.
     body: &'me Body<'tcx>,
@@ -570,7 +571,7 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
     }
 
     fn make_all_regions_live(
-        elements: &RegionValueElements,
+        elements: &DenseLocationMap,
         typeck: &mut TypeChecker<'_, 'tcx>,
         value: impl TypeVisitable<TyCtxt<'tcx>>,
         live_at: &IntervalSet<PointIndex>,

Diff for: compiler/rustc_borrowck/src/type_check/mod.rs

@@ -35,6 +35,7 @@ use rustc_middle::ty::{
     OpaqueHiddenType, OpaqueTypeKey, RegionVid, Ty, TyCtxt, UserType, UserTypeAnnotationIndex,
 };
 use rustc_middle::ty::{GenericArgsRef, UserArgs};
+use rustc_mir_dataflow::points::DenseLocationMap;
 use rustc_span::def_id::CRATE_DEF_ID;
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::sym;
@@ -59,9 +60,7 @@ use crate::{
     location::LocationTable,
     member_constraints::MemberConstraintSet,
     path_utils,
-    region_infer::values::{
-        LivenessValues, PlaceholderIndex, PlaceholderIndices, RegionValueElements,
-    },
+    region_infer::values::{LivenessValues, PlaceholderIndex, PlaceholderIndices},
     region_infer::TypeTest,
     type_check::free_region_relations::{CreateResult, UniversalRegionRelations},
     universal_regions::{DefiningTy, UniversalRegions},
@@ -134,7 +133,7 @@ pub(crate) fn type_check<'mir, 'tcx>(
     all_facts: &mut Option<AllFacts>,
     flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
     move_data: &MoveData<'tcx>,
-    elements: &Rc<RegionValueElements>,
+    elements: &Rc<DenseLocationMap>,
     upvars: &[&ty::CapturedPlace<'tcx>],
     use_polonius: bool,
 ) -> MirTypeckResults<'tcx> {
@@ -556,7 +555,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
         let all_facts = &mut None;
         let mut constraints = Default::default();
         let mut liveness_constraints =
-            LivenessValues::new(Rc::new(RegionValueElements::new(promoted_body)));
+            LivenessValues::new(Rc::new(DenseLocationMap::new(promoted_body)));
         // Don't try to add borrow_region facts for the promoted MIR
 
         let mut swap_constraints = |this: &mut Self| {