Rollup merge of #49030 - Zoxc:misc, r=michaelwoerister

Misc changes from my parallel rustc branch

r? @michaelwoerister

src/librustc/middle/const_val.rs

@@ -19,7 +19,7 @@ use graphviz::IntoCow;
 use syntax_pos::Span;
 
 use std::borrow::Cow;
-use std::rc::Rc;
+use rustc_data_structures::sync::Lrc;
 
 pub type EvalResult<'tcx> = Result<&'tcx ty::Const<'tcx>, ConstEvalErr<'tcx>>;
 
@@ -52,7 +52,7 @@ impl<'tcx> ConstVal<'tcx> {
 #[derive(Clone, Debug)]
 pub struct ConstEvalErr<'tcx> {
     pub span: Span,
-    pub kind: Rc<ErrKind<'tcx>>,
+    pub kind: Lrc<ErrKind<'tcx>>,
 }
 
 #[derive(Clone, Debug)]

src/librustc/traits/query/dropck_outlives.rs

@@ -15,7 +15,7 @@ use std::iter::FromIterator;
 use traits::query::CanonicalTyGoal;
 use ty::{self, Ty, TyCtxt};
 use ty::subst::Kind;
-use std::rc::Rc;
+use rustc_data_structures::sync::Lrc;
 
 impl<'cx, 'gcx, 'tcx> At<'cx, 'gcx, 'tcx> {
     /// Given a type `ty` of some value being dropped, computes a set
@@ -183,13 +183,13 @@ impl_stable_hash_for!(struct DropckOutlivesResult<'tcx> {
 
 impl<'gcx: 'tcx, 'tcx> Canonicalize<'gcx, 'tcx> for QueryResult<'tcx, DropckOutlivesResult<'tcx>> {
     // we ought to intern this, but I'm too lazy just now
-    type Canonicalized = Rc<Canonical<'gcx, QueryResult<'gcx, DropckOutlivesResult<'gcx>>>>;
+    type Canonicalized = Lrc<Canonical<'gcx, QueryResult<'gcx, DropckOutlivesResult<'gcx>>>>;
 
     fn intern(
         _gcx: TyCtxt<'_, 'gcx, 'gcx>,
         value: Canonical<'gcx, Self::Lifted>,
     ) -> Self::Canonicalized {
-        Rc::new(value)
+        Lrc::new(value)
     }
 }
 

src/librustc/traits/query/normalize.rs

@@ -17,7 +17,7 @@ use infer::at::At;
 use infer::canonical::{Canonical, Canonicalize, QueryResult};
 use middle::const_val::ConstVal;
 use mir::interpret::GlobalId;
-use std::rc::Rc;
+use rustc_data_structures::sync::Lrc;
 use traits::{Obligation, ObligationCause, PredicateObligation, Reveal};
 use traits::query::CanonicalProjectionGoal;
 use traits::project::Normalized;
@@ -259,13 +259,13 @@ impl<'gcx: 'tcx, 'tcx> Canonicalize<'gcx, 'tcx> for ty::ParamEnvAnd<'tcx, ty::Pr
 
 impl<'gcx: 'tcx, 'tcx> Canonicalize<'gcx, 'tcx> for QueryResult<'tcx, NormalizationResult<'tcx>> {
     // we ought to intern this, but I'm too lazy just now
-    type Canonicalized = Rc<Canonical<'gcx, QueryResult<'gcx, NormalizationResult<'gcx>>>>;
+    type Canonicalized = Lrc<Canonical<'gcx, QueryResult<'gcx, NormalizationResult<'gcx>>>>;
 
     fn intern(
         _gcx: TyCtxt<'_, 'gcx, 'gcx>,
         value: Canonical<'gcx, Self::Lifted>,
     ) -> Self::Canonicalized {
-        Rc::new(value)
+        Lrc::new(value)
     }
 }
 

src/librustc/ty/context.rs

@@ -161,12 +161,12 @@ impl<'gcx: 'tcx, 'tcx> CtxtInterners<'tcx> {
                  -> Ty<'tcx> {
         let ty = {
             let mut interner = self.type_.borrow_mut();
-            let global_interner = global_interners.map(|interners| {
-                interners.type_.borrow_mut()
-            });
             if let Some(&Interned(ty)) = interner.get(&st) {
                 return ty;
             }
+            let global_interner = global_interners.map(|interners| {
+                interners.type_.borrow_mut()
+            });
             if let Some(ref interner) = global_interner {
                 if let Some(&Interned(ty)) = interner.get(&st) {
                     return ty;
@@ -1010,17 +1010,16 @@ impl<'tcx> InterpretInterner<'tcx> {
     }
 }
 
-impl<'tcx> GlobalCtxt<'tcx> {
+impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
     /// Get the global TyCtxt.
-    pub fn global_tcx<'a>(&'a self) -> TyCtxt<'a, 'tcx, 'tcx> {
+    #[inline]
+    pub fn global_tcx(self) -> TyCtxt<'a, 'gcx, 'gcx> {
         TyCtxt {
-            gcx: self,
-            interners: &self.global_interners
+            gcx: self.gcx,
+            interners: &self.gcx.global_interners,
         }
     }
-}
 
-impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
     pub fn alloc_generics(self, generics: ty::Generics) -> &'gcx ty::Generics {
         self.global_arenas.generics.alloc(generics)
     }
@@ -1081,12 +1080,13 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         self,
         alloc: interpret::Allocation,
     ) -> &'gcx interpret::Allocation {
-        if let Some(alloc) = self.interpret_interner.inner.borrow().allocs.get(&alloc) {
+        let allocs = &mut self.interpret_interner.inner.borrow_mut().allocs;
+        if let Some(alloc) = allocs.get(&alloc) {
             return alloc;
         }
 
         let interned = self.global_arenas.const_allocs.alloc(alloc);
-        if let Some(prev) = self.interpret_interner.inner.borrow_mut().allocs.replace(interned) {
+        if let Some(prev) = allocs.replace(interned) {
             bug!("Tried to overwrite interned Allocation: {:#?}", prev)
         }
         interned
@@ -1113,24 +1113,26 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
     }
 
     pub fn intern_stability(self, stab: attr::Stability) -> &'gcx attr::Stability {
-        if let Some(st) = self.stability_interner.borrow().get(&stab) {
+        let mut stability_interner = self.stability_interner.borrow_mut();
+        if let Some(st) = stability_interner.get(&stab) {
             return st;
         }
 
         let interned = self.global_interners.arena.alloc(stab);
-        if let Some(prev) = self.stability_interner.borrow_mut().replace(interned) {
+        if let Some(prev) = stability_interner.replace(interned) {
             bug!("Tried to overwrite interned Stability: {:?}", prev)
         }
         interned
     }
 
     pub fn intern_layout(self, layout: LayoutDetails) -> &'gcx LayoutDetails {
-        if let Some(layout) = self.layout_interner.borrow().get(&layout) {
+        let mut layout_interner = self.layout_interner.borrow_mut();
+        if let Some(layout) = layout_interner.get(&layout) {
             return layout;
         }
 
         let interned = self.global_arenas.layout.alloc(layout);
-        if let Some(prev) = self.layout_interner.borrow_mut().replace(interned) {
+        if let Some(prev) = layout_interner.replace(interned) {
             bug!("Tried to overwrite interned Layout: {:?}", prev)
         }
         interned

src/librustc/ty/structural_impls.rs

@@ -18,6 +18,7 @@ use ty::{self, Lift, Ty, TyCtxt};
 use ty::fold::{TypeFoldable, TypeFolder, TypeVisitor};
 use rustc_data_structures::accumulate_vec::AccumulateVec;
 use rustc_data_structures::indexed_vec::{IndexVec, Idx};
+use rustc_data_structures::sync::Lrc;
 use mir::interpret;
 
 use std::rc::Rc;
@@ -465,7 +466,7 @@ impl<'a, 'tcx> Lift<'tcx> for ConstEvalErr<'a> {
         tcx.lift(&*self.kind).map(|kind| {
             ConstEvalErr {
                 span: self.span,
-                kind: Rc::new(kind),
+                kind: Lrc::new(kind),
             }
         })
     }