Merge from rustc

Author: RalfJung

Cargo.lock

@@ -3784,6 +3784,7 @@ dependencies = [
 name = "rustc_driver_impl"
 version = "0.0.0"
 dependencies = [
+ "ctrlc",
  "libc",
  "rustc_ast",
  "rustc_ast_lowering",

compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -95,9 +95,11 @@ pub struct RegionInferenceContext<'tcx> {
     /// visible from this index.
     scc_universes: IndexVec<ConstraintSccIndex, ty::UniverseIndex>,
 
-    /// Contains a "representative" from each SCC. This will be the
-    /// minimal RegionVid belonging to that universe. It is used as a
-    /// kind of hacky way to manage checking outlives relationships,
+    /// Contains the "representative" region of each SCC.
+    /// It is defined as the one with the minimal RegionVid, favoring
+    /// free regions, then placeholders, then existential regions.
+    ///
+    /// It is a hacky way to manage checking regions for equality,
     /// since we can 'canonicalize' each region to the representative
     /// of its SCC and be sure that -- if they have the same repr --
     /// they *must* be equal (though not having the same repr does not
@@ -481,22 +483,28 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         scc_universes
     }
 
-    /// For each SCC, we compute a unique `RegionVid` (in fact, the
-    /// minimal one that belongs to the SCC). See
+    /// For each SCC, we compute a unique `RegionVid`. See the
     /// `scc_representatives` field of `RegionInferenceContext` for
     /// more details.
     fn compute_scc_representatives(
         constraints_scc: &Sccs<RegionVid, ConstraintSccIndex>,
         definitions: &IndexSlice<RegionVid, RegionDefinition<'tcx>>,
     ) -> IndexVec<ConstraintSccIndex, ty::RegionVid> {
         let num_sccs = constraints_scc.num_sccs();
-        let next_region_vid = definitions.next_index();
-        let mut scc_representatives = IndexVec::from_elem_n(next_region_vid, num_sccs);
-
-        for region_vid in definitions.indices() {
-            let scc = constraints_scc.scc(region_vid);
-            let prev_min = scc_representatives[scc];
-            scc_representatives[scc] = region_vid.min(prev_min);
+        let mut scc_representatives = IndexVec::from_elem_n(RegionVid::MAX, num_sccs);
+
+        // Iterate over all RegionVids *in-order* and pick the least RegionVid as the
+        // representative of its SCC. This naturally prefers free regions over others.
+        for (vid, def) in definitions.iter_enumerated() {
+            let repr = &mut scc_representatives[constraints_scc.scc(vid)];
+            if *repr == ty::RegionVid::MAX {
+                *repr = vid;
+            } else if matches!(def.origin, NllRegionVariableOrigin::Placeholder(_))
+                && matches!(definitions[*repr].origin, NllRegionVariableOrigin::Existential { .. })
+            {
+                // Pick placeholders over existentials even if they have a greater RegionVid.
+                *repr = vid;
+            }
         }
 
         scc_representatives

compiler/rustc_borrowck/src/region_infer/opaque_types.rs

@@ -1,6 +1,5 @@
 use crate::constraints::ConstraintSccIndex;
 use crate::RegionInferenceContext;
-use itertools::Itertools;
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_data_structures::graph::vec_graph::VecGraph;
 use rustc_data_structures::graph::WithSuccessors;
@@ -48,16 +47,16 @@ impl RegionInferenceContext<'_> {
             .universal_regions
             .universal_regions()
             .map(|region| (self.constraint_sccs.scc(region), region))
-            .collect_vec();
+            .collect::<Vec<_>>();
         paired_scc_regions.sort();
         let universal_regions = paired_scc_regions.iter().map(|&(_, region)| region).collect();
 
         let mut scc_regions = FxIndexMap::default();
         let mut start = 0;
-        for (scc, group) in &paired_scc_regions.into_iter().group_by(|(scc, _)| *scc) {
-            let group_size = group.count();
-            scc_regions.insert(scc, start..start + group_size);
-            start += group_size;
+        for chunk in paired_scc_regions.chunk_by(|&(scc1, _), &(scc2, _)| scc1 == scc2) {
+            let (scc, _) = chunk[0];
+            scc_regions.insert(scc, start..start + chunk.len());
+            start += chunk.len();
         }
 
         self.rev_scc_graph = Some(ReverseSccGraph { graph, scc_regions, universal_regions });

compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs

@@ -164,6 +164,13 @@ impl UniversalRegionRelations<'_> {
         self.outlives.contains(fr1, fr2)
     }
 
+    /// Returns `true` if fr1 is known to equal fr2.
+    ///
+    /// This will only ever be true for universally quantified regions.
+    pub(crate) fn equal(&self, fr1: RegionVid, fr2: RegionVid) -> bool {
+        self.outlives.contains(fr1, fr2) && self.outlives.contains(fr2, fr1)
+    }
+
     /// Returns a vector of free regions `x` such that `fr1: x` is
     /// known to hold.
     pub(crate) fn regions_outlived_by(&self, fr1: RegionVid) -> Vec<RegionVid> {

compiler/rustc_borrowck/src/type_check/free_region_relations.rs

@@ -229,6 +229,22 @@ pub(crate) fn type_check<'mir, 'tcx>(
                 );
             }
 
+            // Convert all regions to nll vars.
+            let (opaque_type_key, hidden_type) =
+                infcx.tcx.fold_regions((opaque_type_key, hidden_type), |region, _| {
+                    match region.kind() {
+                        ty::ReVar(_) => region,
+                        ty::RePlaceholder(placeholder) => checker
+                            .borrowck_context
+                            .constraints
+                            .placeholder_region(infcx, placeholder),
+                        _ => ty::Region::new_var(
+                            infcx.tcx,
+                            checker.borrowck_context.universal_regions.to_region_vid(region),
+                        ),
+                    }
+                });
+
             (opaque_type_key, hidden_type)
         })
         .collect();

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -41,21 +41,6 @@ rm tests/ui/parser/unclosed-delimiter-in-dep.rs # submodule contains //~ERROR
 # missing features
 # ================
 
-# requires stack unwinding
-# FIXME add needs-unwind to these tests
-rm -r tests/run-make/libtest-junit
-rm tests/ui/asm/may_unwind.rs
-rm tests/ui/stable-mir-print/basic_function.rs
-
-# extra warning about -Cpanic=abort for proc macros
-rm tests/ui/proc-macro/crt-static.rs
-rm tests/ui/proc-macro/proc-macro-deprecated-attr.rs
-rm tests/ui/proc-macro/quote-debug.rs
-rm tests/ui/proc-macro/no-missing-docs.rs
-rm tests/ui/rust-2018/proc-macro-crate-in-paths.rs
-rm tests/ui/proc-macro/allowed-signatures.rs
-rm tests/ui/proc-macro/no-mangle-in-proc-macro-issue-111888.rs
-
 # vendor intrinsics
 rm tests/ui/simd/array-type.rs # "Index argument for `simd_insert` is not a constant"
 rm tests/ui/asm/x86_64/evex512-implicit-feature.rs # unimplemented AVX512 x86 vendor intrinsic
@@ -154,7 +139,6 @@ rm tests/ui/codegen/subtyping-enforces-type-equality.rs # assert_assignable bug
 # ======================
 rm tests/ui/backtrace.rs # TODO warning
 rm tests/ui/process/nofile-limit.rs # TODO some AArch64 linking issue
-rm tests/ui/async-await/async-closures/once.rs # FIXME bug in the rustc FnAbi calculation code
 
 rm tests/ui/stdio-is-blocking.rs # really slow with unoptimized libstd
 

compiler/rustc_codegen_cranelift/scripts/test_rustc_tests.sh

@@ -20,6 +20,7 @@ use rustc_middle::ty::layout::{
     FnAbiError, FnAbiOfHelpers, FnAbiRequest, LayoutError, LayoutOfHelpers, TyAndLayout,
 };
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
+use rustc_session::config::OptLevel;
 use rustc_span::Span;
 use rustc_symbol_mangling::typeid::{
     kcfi_typeid_for_fnabi, kcfi_typeid_for_instance, typeid_for_fnabi, typeid_for_instance,
@@ -551,6 +552,11 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
             layout: TyAndLayout<'tcx>,
             offset: Size,
         ) {
+            if bx.cx.sess().opts.optimize == OptLevel::No {
+                // Don't emit metadata we're not going to use
+                return;
+            }
+
             if !scalar.is_uninit_valid() {
                 bx.noundef_metadata(load);
             }
@@ -667,6 +673,11 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
             return;
         }
 
+        if self.cx.sess().opts.optimize == OptLevel::No {
+            // Don't emit metadata we're not going to use
+            return;
+        }
+
         unsafe {
             let llty = self.cx.val_ty(load);
             let v = [
@@ -1630,7 +1641,7 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
             }
 
             let typeid = if let Some(instance) = instance {
-                typeid_for_instance(self.tcx, &instance, options)
+                typeid_for_instance(self.tcx, instance, options)
             } else {
                 typeid_for_fnabi(self.tcx, fn_abi, options)
             };
@@ -1678,7 +1689,7 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
             }
 
             let kcfi_typeid = if let Some(instance) = instance {
-                kcfi_typeid_for_instance(self.tcx, &instance, options)
+                kcfi_typeid_for_instance(self.tcx, instance, options)
             } else {
                 kcfi_typeid_for_fnabi(self.tcx, fn_abi, options)
             };

compiler/rustc_codegen_llvm/src/builder.rs

@@ -141,17 +141,17 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> {
 
         if self.tcx.sess.is_sanitizer_cfi_enabled() {
             if let Some(instance) = instance {
-                let typeid = typeid_for_instance(self.tcx, &instance, TypeIdOptions::empty());
+                let typeid = typeid_for_instance(self.tcx, instance, TypeIdOptions::empty());
                 self.set_type_metadata(llfn, typeid);
                 let typeid =
-                    typeid_for_instance(self.tcx, &instance, TypeIdOptions::GENERALIZE_POINTERS);
+                    typeid_for_instance(self.tcx, instance, TypeIdOptions::GENERALIZE_POINTERS);
                 self.add_type_metadata(llfn, typeid);
                 let typeid =
-                    typeid_for_instance(self.tcx, &instance, TypeIdOptions::NORMALIZE_INTEGERS);
+                    typeid_for_instance(self.tcx, instance, TypeIdOptions::NORMALIZE_INTEGERS);
                 self.add_type_metadata(llfn, typeid);
                 let typeid = typeid_for_instance(
                     self.tcx,
-                    &instance,
+                    instance,
                     TypeIdOptions::GENERALIZE_POINTERS | TypeIdOptions::NORMALIZE_INTEGERS,
                 );
                 self.add_type_metadata(llfn, typeid);
@@ -182,7 +182,7 @@ impl<'ll, 'tcx> CodegenCx<'ll, 'tcx> {
             }
 
             if let Some(instance) = instance {
-                let kcfi_typeid = kcfi_typeid_for_instance(self.tcx, &instance, options);
+                let kcfi_typeid = kcfi_typeid_for_instance(self.tcx, instance, options);
                 self.set_kcfi_type_metadata(llfn, kcfi_typeid);
             } else {
                 let kcfi_typeid = kcfi_typeid_for_fnabi(self.tcx, fn_abi, options);

compiler/rustc_codegen_llvm/src/declare.rs

@@ -592,7 +592,7 @@ fn produce_final_output_artifacts(
                 .unwrap()
                 .to_owned();
 
-            if crate_output.outputs.contains_key(&output_type) {
+            if crate_output.outputs.contains_explicit_name(&output_type) {
                 // 2) Multiple codegen units, with `--emit foo=some_name`. We have
                 //    no good solution for this case, so warn the user.
                 sess.dcx().emit_warn(errors::IgnoringEmitPath { extension });