Rollup of 6 pull requests

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -736,11 +736,10 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                         this.visit_expr(&arm.body);
                         this.visit_pat(&arm.pat);
                         walk_list!(this, visit_attribute, &arm.attrs);
-                        if let Some(guard) = &arm.guard && let ExprKind::Let(_, guard_expr, _) = &guard.kind {
+                        if let Some(guard) = &arm.guard {
                             this.with_let_management(None, |this, _| {
-                                this.visit_expr(guard_expr)
+                                this.visit_expr(guard)
                             });
-                            return;
                         }
                     }
                 }

compiler/rustc_borrowck/src/dataflow.rs

@@ -156,10 +156,10 @@ impl<'tcx> OutOfScopePrecomputer<'_, 'tcx> {
         &mut self,
         borrow_index: BorrowIndex,
         borrow_region: RegionVid,
-        location: Location,
+        first_location: Location,
     ) {
         // We visit one BB at a time. The complication is that we may start in the
-        // middle of the first BB visited (the one containing `location`), in which
+        // middle of the first BB visited (the one containing `first_location`), in which
         // case we may have to later on process the first part of that BB if there
         // is a path back to its start.
 
@@ -168,61 +168,58 @@ impl<'tcx> OutOfScopePrecomputer<'_, 'tcx> {
         // `visited` once they are added to `stack`, before they are actually
         // processed, because this avoids the need to look them up again on
         // completion.
-        self.visited.insert(location.block);
+        self.visited.insert(first_location.block);
 
-        let mut first_lo = location.statement_index;
-        let first_hi = self.body[location.block].statements.len();
+        let first_block = first_location.block;
+        let mut first_lo = first_location.statement_index;
+        let first_hi = self.body[first_block].statements.len();
 
-        self.visit_stack.push(StackEntry { bb: location.block, lo: first_lo, hi: first_hi });
+        self.visit_stack.push(StackEntry { bb: first_block, lo: first_lo, hi: first_hi });
 
-        while let Some(StackEntry { bb, lo, hi }) = self.visit_stack.pop() {
-            // If we process the first part of the first basic block (i.e. we encounter that block
-            // for the second time), we no longer have to visit its successors again.
-            let mut finished_early = bb == location.block && hi != first_hi;
-            for i in lo..=hi {
-                let location = Location { block: bb, statement_index: i };
+        'preorder: while let Some(StackEntry { bb, lo, hi }) = self.visit_stack.pop() {
+            if let Some(kill_stmt) =
+                self.regioncx.first_non_contained_inclusive(borrow_region, bb, lo, hi)
+            {
+                let kill_location = Location { block: bb, statement_index: kill_stmt };
                 // If region does not contain a point at the location, then add to list and skip
                 // successor locations.
-                if !self.regioncx.region_contains(borrow_region, location) {
-                    debug!("borrow {:?} gets killed at {:?}", borrow_index, location);
-                    self.borrows_out_of_scope_at_location
-                        .entry(location)
-                        .or_default()
-                        .push(borrow_index);
-                    finished_early = true;
-                    break;
-                }
+                debug!("borrow {:?} gets killed at {:?}", borrow_index, kill_location);
+                self.borrows_out_of_scope_at_location
+                    .entry(kill_location)
+                    .or_default()
+                    .push(borrow_index);
+                continue 'preorder;
             }
 
-            if !finished_early {
-                // Add successor BBs to the work list, if necessary.
-                let bb_data = &self.body[bb];
-                debug_assert!(hi == bb_data.statements.len());
-                for succ_bb in bb_data.terminator().successors() {
-                    if !self.visited.insert(succ_bb) {
-                        if succ_bb == location.block && first_lo > 0 {
-                            // `succ_bb` has been seen before. If it wasn't
-                            // fully processed, add its first part to `stack`
-                            // for processing.
-                            self.visit_stack.push(StackEntry {
-                                bb: succ_bb,
-                                lo: 0,
-                                hi: first_lo - 1,
-                            });
-
-                            // And update this entry with 0, to represent the
-                            // whole BB being processed.
-                            first_lo = 0;
-                        }
-                    } else {
-                        // succ_bb hasn't been seen before. Add it to
-                        // `stack` for processing.
-                        self.visit_stack.push(StackEntry {
-                            bb: succ_bb,
-                            lo: 0,
-                            hi: self.body[succ_bb].statements.len(),
-                        });
+            // If we process the first part of the first basic block (i.e. we encounter that block
+            // for the second time), we no longer have to visit its successors again.
+            if bb == first_block && hi != first_hi {
+                continue;
+            }
+
+            // Add successor BBs to the work list, if necessary.
+            let bb_data = &self.body[bb];
+            debug_assert!(hi == bb_data.statements.len());
+            for succ_bb in bb_data.terminator().successors() {
+                if !self.visited.insert(succ_bb) {
+                    if succ_bb == first_block && first_lo > 0 {
+                        // `succ_bb` has been seen before. If it wasn't
+                        // fully processed, add its first part to `stack`
+                        // for processing.
+                        self.visit_stack.push(StackEntry { bb: succ_bb, lo: 0, hi: first_lo - 1 });
+
+                        // And update this entry with 0, to represent the
+                        // whole BB being processed.
+                        first_lo = 0;
                     }
+                } else {
+                    // succ_bb hasn't been seen before. Add it to
+                    // `stack` for processing.
+                    self.visit_stack.push(StackEntry {
+                        bb: succ_bb,
+                        lo: 0,
+                        hi: self.body[succ_bb].statements.len(),
+                    });
                 }
             }
         }

compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -12,7 +12,7 @@ use rustc_infer::infer::outlives::test_type_match;
 use rustc_infer::infer::region_constraints::{GenericKind, VarInfos, VerifyBound, VerifyIfEq};
 use rustc_infer::infer::{InferCtxt, NllRegionVariableOrigin, RegionVariableOrigin};
 use rustc_middle::mir::{
-    Body, ClosureOutlivesRequirement, ClosureOutlivesSubject, ClosureOutlivesSubjectTy,
+    BasicBlock, Body, ClosureOutlivesRequirement, ClosureOutlivesSubject, ClosureOutlivesSubjectTy,
     ClosureRegionRequirements, ConstraintCategory, Local, Location, ReturnConstraint,
     TerminatorKind,
 };
@@ -598,6 +598,20 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         self.scc_values.contains(scc, p)
     }
 
+    /// Returns the lowest statement index in `start..=end` which is not contained by `r`.
+    ///
+    /// Panics if called before `solve()` executes.
+    pub(crate) fn first_non_contained_inclusive(
+        &self,
+        r: RegionVid,
+        block: BasicBlock,
+        start: usize,
+        end: usize,
+    ) -> Option<usize> {
+        let scc = self.constraint_sccs.scc(r);
+        self.scc_values.first_non_contained_inclusive(scc, block, start, end)
+    }
+
     /// Returns access to the value of `r` for debugging purposes.
     pub(crate) fn region_value_str(&self, r: RegionVid) -> String {
         let scc = self.constraint_sccs.scc(r);

compiler/rustc_borrowck/src/region_infer/values.rs

@@ -283,6 +283,22 @@ impl<N: Idx> RegionValues<N> {
         elem.contained_in_row(self, r)
     }
 
+    /// Returns the lowest statement index in `start..=end` which is not contained by `r`.
+    pub(crate) fn first_non_contained_inclusive(
+        &self,
+        r: N,
+        block: BasicBlock,
+        start: usize,
+        end: usize,
+    ) -> Option<usize> {
+        let row = self.points.row(r)?;
+        let block = self.elements.entry_point(block);
+        let start = block.plus(start);
+        let end = block.plus(end);
+        let first_unset = row.first_unset_in(start..=end)?;
+        Some(first_unset.index() - block.index())
+    }
+
     /// `self[to] |= values[from]`, essentially: that is, take all the
     /// elements for the region `from` from `values` and add them to
     /// the region `to` in `self`.

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -183,17 +183,10 @@ pub(crate) fn type_check<'mir, 'tcx>(
         &mut borrowck_context,
     );
 
-    let errors_reported = {
-        let mut verifier = TypeVerifier::new(&mut checker, promoted);
-        verifier.visit_body(&body);
-        verifier.errors_reported
-    };
-
-    if !errors_reported {
-        // if verifier failed, don't do further checks to avoid ICEs
-        checker.typeck_mir(body);
-    }
+    let mut verifier = TypeVerifier::new(&mut checker, promoted);
+    verifier.visit_body(&body);
 
+    checker.typeck_mir(body);
     checker.equate_inputs_and_outputs(&body, universal_regions, &normalized_inputs_and_output);
     checker.check_signature_annotation(&body);
 
@@ -294,7 +287,6 @@ struct TypeVerifier<'a, 'b, 'tcx> {
     cx: &'a mut TypeChecker<'b, 'tcx>,
     promoted: &'b IndexSlice<Promoted, Body<'tcx>>,
     last_span: Span,
-    errors_reported: bool,
 }
 
 impl<'a, 'b, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'tcx> {
@@ -383,13 +375,11 @@ impl<'a, 'b, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'tcx> {
                         };
                     };
 
-                    if !self.errors_reported {
-                        let promoted_body = &self.promoted[promoted];
-                        self.sanitize_promoted(promoted_body, location);
+                    let promoted_body = &self.promoted[promoted];
+                    self.sanitize_promoted(promoted_body, location);
 
-                        let promoted_ty = promoted_body.return_ty();
-                        check_err(self, promoted_body, ty, promoted_ty);
-                    }
+                    let promoted_ty = promoted_body.return_ty();
+                    check_err(self, promoted_body, ty, promoted_ty);
                 } else {
                     self.cx.ascribe_user_type(
                         constant.literal.ty(),
@@ -483,9 +473,6 @@ impl<'a, 'b, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'tcx> {
         for local_decl in &body.local_decls {
             self.sanitize_type(local_decl, local_decl.ty);
         }
-        if self.errors_reported {
-            return;
-        }
         self.super_body(body);
     }
 }
@@ -495,7 +482,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
         cx: &'a mut TypeChecker<'b, 'tcx>,
         promoted: &'b IndexSlice<Promoted, Body<'tcx>>,
     ) -> Self {
-        TypeVerifier { promoted, last_span: cx.body.span, cx, errors_reported: false }
+        TypeVerifier { promoted, last_span: cx.body.span, cx }
     }
 
     fn body(&self) -> &Body<'tcx> {
@@ -529,7 +516,6 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
         for elem in place.projection.iter() {
             if place_ty.variant_index.is_none() {
                 if let Err(guar) = place_ty.ty.error_reported() {
-                    assert!(self.errors_reported);
                     return PlaceTy::from_ty(self.tcx().ty_error(guar));
                 }
             }
@@ -593,10 +579,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
 
         self.visit_body(&promoted_body);
 
-        if !self.errors_reported {
-            // if verifier failed, don't do further checks to avoid ICEs
-            self.cx.typeck_mir(promoted_body);
-        }
+        self.cx.typeck_mir(promoted_body);
 
         self.cx.body = parent_body;
         // Merge the outlives constraints back in, at the given location.
@@ -762,7 +745,6 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
     }
 
     fn error(&mut self) -> Ty<'tcx> {
-        self.errors_reported = true;
         self.tcx().ty_error_misc()
     }