Adding upstream version 1.66.0+dfsg1.upstream/1.66.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 59 insertions, 129 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 0c06aad4e..396782d45 100644
--- a/compiler/rustc_mir_build/src/build/expr/as_place.rs
+++ b/compiler/rustc_mir_build/src/build/expr/as_place.rs
@@ -2,7 +2,7 @@
 
 use crate::build::expr::category::Category;
 use crate::build::ForGuard::{OutsideGuard, RefWithinGuard};
-use crate::build::{BlockAnd, BlockAndExtension, Builder};
+use crate::build::{BlockAnd, BlockAndExtension, Builder, Capture, CaptureMap};
 use rustc_hir::def_id::LocalDefId;
 use rustc_middle::hir::place::Projection as HirProjection;
 use rustc_middle::hir::place::ProjectionKind as HirProjectionKind;
@@ -17,6 +17,7 @@ use rustc_target::abi::VariantIdx;
 
 use rustc_index::vec::Idx;
 
+use std::assert_matches::assert_matches;
 use std::iter;
 
 /// The "outermost" place that holds this value.
@@ -59,8 +60,6 @@ pub(crate) enum PlaceBase {
         var_hir_id: LocalVarId,
         /// DefId of the closure
         closure_def_id: LocalDefId,
-        /// The trait closure implements, `Fn`, `FnMut`, `FnOnce`
-        closure_kind: ty::ClosureKind,
     },
 }
 
@@ -71,7 +70,7 @@ 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 +103,8 @@ 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 { .. } => {
@@ -145,27 +146,6 @@ fn is_ancestor_or_same_capture(
     iter::zip(proj_possible_ancestor, proj_capture).all(|(a, b)| a == b)
 }
 
-/// Computes the index of a capture within the desugared closure provided the closure's
-/// `closure_min_captures` and the capture's index of the capture in the
-/// `ty::MinCaptureList` of the root variable `var_hir_id`.
-fn compute_capture_idx<'tcx>(
-    closure_min_captures: &ty::RootVariableMinCaptureList<'tcx>,
-    var_hir_id: LocalVarId,
-    root_var_idx: usize,
-) -> usize {
-    let mut res = 0;
-    for (var_id, capture_list) in closure_min_captures {
-        if *var_id == var_hir_id.0 {
-            res += root_var_idx;
-            break;
-        } else {
-            res += capture_list.len();
-        }
-    }
-
-    res
-}
-
 /// Given a closure, returns the index of a capture within the desugared closure struct and the
 /// `ty::CapturedPlace` which is the ancestor of the Place represented using the `var_hir_id`
 /// and `projection`.
@@ -174,58 +154,39 @@ fn compute_capture_idx<'tcx>(
 ///
 /// Returns None, when the ancestor is not found.
 fn find_capture_matching_projections<'a, 'tcx>(
-    typeck_results: &'a ty::TypeckResults<'tcx>,
+    upvars: &'a CaptureMap<'tcx>,
     var_hir_id: LocalVarId,
-    closure_def_id: LocalDefId,
     projections: &[PlaceElem<'tcx>],
-) -> Option<(usize, &'a ty::CapturedPlace<'tcx>)> {
-    let closure_min_captures = typeck_results.closure_min_captures.get(&closure_def_id)?;
-    let root_variable_min_captures = closure_min_captures.get(&var_hir_id.0)?;
-
+) -> Option<(usize, &'a Capture<'tcx>)> {
     let hir_projections = convert_to_hir_projections_and_truncate_for_capture(projections);
 
-    // If an ancestor is found, `idx` is the index within the list of captured places
-    // for root variable `var_hir_id` and `capture` is the `ty::CapturedPlace` itself.
-    let (idx, capture) = root_variable_min_captures.iter().enumerate().find(|(_, capture)| {
+    upvars.get_by_key_enumerated(var_hir_id.0).find(|(_, capture)| {
         let possible_ancestor_proj_kinds: Vec<_> =
-            capture.place.projections.iter().map(|proj| proj.kind).collect();
+            capture.captured_place.place.projections.iter().map(|proj| proj.kind).collect();
         is_ancestor_or_same_capture(&possible_ancestor_proj_kinds, &hir_projections)
-    })?;
-
-    // Convert index to be from the perspective of the entire closure_min_captures map
-    // instead of just the root variable capture list
-    Some((compute_capture_idx(closure_min_captures, var_hir_id, idx), capture))
+    })
 }
 
 /// Takes a PlaceBuilder and resolves the upvar (if any) within it, so that the
 /// `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), ret)]
+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),
-        PlaceBase::Upvar { var_hir_id, closure_def_id, closure_kind } => {
-            let mut upvar_resolved_place_builder = PlaceBuilder::from(ty::CAPTURE_STRUCT_LOCAL);
-            match closure_kind {
-                ty::ClosureKind::Fn | ty::ClosureKind::FnMut => {
-                    upvar_resolved_place_builder = upvar_resolved_place_builder.deref();
-                }
-                ty::ClosureKind::FnOnce => {}
-            }
-
+        PlaceBase::Upvar { var_hir_id, closure_def_id } => {
             let Some((capture_index, capture)) =
                 find_capture_matching_projections(
-                    typeck_results,
+                    &cx.upvars,
                     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",
@@ -241,39 +202,18 @@ fn to_upvars_resolved_place_builder<'a, 'tcx>(
                 return Err(from_builder);
             };
 
-            // 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);
-            let closure_ty = typeck_results.node_type(closure_hir_id);
-
-            let substs = match closure_ty.kind() {
-                ty::Closure(_, substs) => ty::UpvarSubsts::Closure(substs),
-                ty::Generator(_, substs, _) => ty::UpvarSubsts::Generator(substs),
-                _ => bug!("Lowering capture for non-closure type {:?}", closure_ty),
-            };
-
             // Access the capture by accessing the field within the Closure struct.
-            //
-            // We must have inferred the capture types since we are building MIR, therefore
-            // it's safe to call `tuple_element_ty` and we can unwrap here because
-            // we know that the capture exists and is the `capture_index`-th capture.
-            let var_ty = substs.tupled_upvars_ty().tuple_fields()[capture_index];
-
-            upvar_resolved_place_builder =
-                upvar_resolved_place_builder.field(Field::new(capture_index), var_ty);
-
-            // If the variable is captured via ByRef(Immutable/Mutable) Borrow,
-            // we need to deref it
-            upvar_resolved_place_builder = match capture.info.capture_kind {
-                ty::UpvarCapture::ByRef(_) => upvar_resolved_place_builder.deref(),
-                ty::UpvarCapture::ByValue => upvar_resolved_place_builder,
-            };
+            let capture_info = &cx.upvars[capture_index];
+
+            let mut upvar_resolved_place_builder = PlaceBuilder::from(capture_info.use_place);
 
             // We used some of the projections to build the capture itself,
             // now we apply the remaining to the upvar resolved place.
+            trace!(?capture.captured_place, ?from_builder.projection);
             let remaining_projections = strip_prefix(
-                capture.place.base_ty,
+                capture.captured_place.place.base_ty,
                 from_builder.projection,
-                &capture.place.projections,
+                &capture.captured_place.place.projections,
             );
             upvar_resolved_place_builder.projection.extend(remaining_projections);
 
@@ -293,17 +233,20 @@ fn strip_prefix<'tcx>(
     projections: Vec<PlaceElem<'tcx>>,
     prefix_projections: &[HirProjection<'tcx>],
 ) -> impl Iterator<Item = PlaceElem<'tcx>> {
-    let mut iter = projections.into_iter();
+    let mut iter = projections
+        .into_iter()
+        // Filter out opaque casts, they are unnecessary in the prefix.
+        .filter(|elem| !matches!(elem, ProjectionElem::OpaqueCast(..)));
     for projection in prefix_projections {
         match projection.kind {
             HirProjectionKind::Deref => {
-                assert!(matches!(iter.next(), Some(ProjectionElem::Deref)));
+                assert_matches!(iter.next(), Some(ProjectionElem::Deref));
             }
             HirProjectionKind::Field(..) => {
                 if base_ty.is_enum() {
-                    assert!(matches!(iter.next(), Some(ProjectionElem::Downcast(..))));
+                    assert_matches!(iter.next(), Some(ProjectionElem::Downcast(..)));
                 }
-                assert!(matches!(iter.next(), Some(ProjectionElem::Field(..))));
+                assert_matches!(iter.next(), Some(ProjectionElem::Field(..)));
             }
             HirProjectionKind::Index | HirProjectionKind::Subslice => {
                 bug!("unexpected projection kind: {:?}", projection);
@@ -315,24 +258,16 @@ 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(in crate::build) 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) }
+            Place { local, projection: cx.tcx.intern_place_elems(&self.projection) }
         } 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`.
@@ -346,18 +281,21 @@ 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(in crate::build) 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 {
         self.base
     }
 
+    pub(crate) fn projection(&self) -> &[PlaceElem<'tcx>] {
+        &self.projection
+    }
+
     pub(crate) fn field(self, f: Field, ty: Ty<'tcx>) -> Self {
         self.project(PlaceElem::Field(f, ty))
     }
@@ -392,6 +330,12 @@ impl<'tcx> From<PlaceBase> for PlaceBuilder<'tcx> {
     }
 }
 
+impl<'tcx> From<Place<'tcx>> for PlaceBuilder<'tcx> {
+    fn from(p: Place<'tcx>) -> Self {
+        Self { base: PlaceBase::Local(p.local), projection: p.projection.to_vec() }
+    }
+}
+
 impl<'a, 'tcx> Builder<'a, 'tcx> {
     /// Compile `expr`, yielding a place that we can move from etc.
     ///
@@ -411,7 +355,7 @@ 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 +379,7 @@ 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
@@ -513,7 +457,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 block.and(place_builder)
             }
 
-            ExprKind::PlaceTypeAscription { source, user_ty } => {
+            ExprKind::PlaceTypeAscription { source, ref user_ty } => {
                 let place_builder = unpack!(
                     block = this.expr_as_place(
                         block,
@@ -526,11 +470,11 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     let annotation_index =
                         this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation {
                             span: source_info.span,
-                            user_ty,
+                            user_ty: user_ty.clone(),
                             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 {
@@ -547,7 +491,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 }
                 block.and(place_builder)
             }
-            ExprKind::ValueTypeAscription { source, user_ty } => {
+            ExprKind::ValueTypeAscription { source, ref user_ty } => {
                 let source = &this.thir[source];
                 let temp =
                     unpack!(block = this.as_temp(block, source.temp_lifetime, source, mutability));
@@ -555,7 +499,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     let annotation_index =
                         this.canonical_user_type_annotations.push(CanonicalUserTypeAnnotation {
                             span: source_info.span,
-                            user_ty,
+                            user_ty: user_ty.clone(),
                             inferred_ty: expr.ty,
                         });
                     this.cfg.push(
@@ -629,17 +573,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         closure_def_id: LocalDefId,
         var_hir_id: LocalVarId,
     ) -> BlockAnd<PlaceBuilder<'tcx>> {
-        let closure_ty =
-            self.typeck_results.node_type(self.tcx.hir().local_def_id_to_hir_id(closure_def_id));
-
-        let closure_kind = if let ty::Closure(_, closure_substs) = closure_ty.kind() {
-            self.infcx.closure_kind(closure_substs).unwrap()
-        } else {
-            // Generators are considered FnOnce.
-            ty::ClosureKind::FnOnce
-        };
-
-        block.and(PlaceBuilder::from(PlaceBase::Upvar { var_hir_id, closure_def_id, closure_kind }))
+        block.and(PlaceBuilder::from(PlaceBase::Upvar { var_hir_id, closure_def_id }))
     }
 
     /// Lower an index expression
@@ -678,7 +612,7 @@ 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,
@@ -706,12 +640,7 @@ 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,
@@ -791,6 +720,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                     }
                     ProjectionElem::Field(..)
                     | ProjectionElem::Downcast(..)
+                    | ProjectionElem::OpaqueCast(..)
                     | ProjectionElem::ConstantIndex { .. }
                     | ProjectionElem::Subslice { .. } => (),
                 }