rustc: Remove the unnecessary ast_ty_to_ty_cache.

Author: eddyb

src/librustc/hir/def.rs

@@ -17,8 +17,7 @@ use hir;
 #[derive(Clone, Copy, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
 pub enum Def {
     Fn(DefId),
-    SelfTy(Option<DefId>,                    // trait id
-              Option<(ast::NodeId, ast::NodeId)>),   // (impl id, self type id)
+    SelfTy(Option<DefId> /* trait */, Option<ast::NodeId> /* impl */),
     Mod(DefId),
     ForeignMod(DefId),
     Static(DefId, bool /* is_mutbl */),

src/librustc/ty/context.rs

@@ -356,11 +356,6 @@ pub struct GlobalCtxt<'tcx> {
     // Cache for the type-contents routine. FIXME -- track deps?
     pub tc_cache: RefCell<FnvHashMap<Ty<'tcx>, ty::contents::TypeContents>>,
 
-    // Cache for various types within a method body and so forth.
-    //
-    // FIXME this should be made local to typeck, but it is currently used by one lint
-    pub ast_ty_to_ty_cache: RefCell<NodeMap<Ty<'tcx>>>,
-
     // FIXME no dep tracking, but we should be able to remove this
     pub ty_param_defs: RefCell<NodeMap<ty::TypeParameterDef<'tcx>>>,
 
@@ -664,7 +659,6 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             tcache: RefCell::new(DepTrackingMap::new(dep_graph.clone())),
             rcache: RefCell::new(FnvHashMap()),
             tc_cache: RefCell::new(FnvHashMap()),
-            ast_ty_to_ty_cache: RefCell::new(NodeMap()),
             impl_or_trait_items: RefCell::new(DepTrackingMap::new(dep_graph.clone())),
             trait_item_def_ids: RefCell::new(DepTrackingMap::new(dep_graph.clone())),
             trait_items_cache: RefCell::new(DepTrackingMap::new(dep_graph.clone())),

src/librustc/ty/sty.rs

@@ -93,10 +93,8 @@ pub enum TypeVariants<'tcx> {
     /// Substs here, possibly against intuition, *may* contain `TyParam`s.
     /// That is, even after substitution it is possible that there are type
     /// variables. This happens when the `TyEnum` corresponds to an enum
-    /// definition and not a concrete use of it. To get the correct `TyEnum`
-    /// from the tcx, use the `NodeId` from the `ast::Ty` and look it up in
-    /// the `ast_ty_to_ty_cache`. This is probably true for `TyStruct` as
-    /// well.
+    /// definition and not a concrete use of it. This is true for `TyStruct`
+    /// as well.
     TyEnum(AdtDef<'tcx>, &'tcx Substs<'tcx>),
 
     /// A structure type, defined with `struct`.

src/librustc_metadata/astencode.rs

@@ -362,11 +362,8 @@ impl tr for Def {
         match *self {
           Def::Fn(did) => Def::Fn(did.tr(dcx)),
           Def::Method(did) => Def::Method(did.tr(dcx)),
-          Def::SelfTy(opt_did, impl_ids) => { Def::SelfTy(opt_did.map(|did| did.tr(dcx)),
-                                                                impl_ids.map(|(nid1, nid2)| {
-                                                                    (dcx.tr_id(nid1),
-                                                                     dcx.tr_id(nid2))
-                                                                })) }
+          Def::SelfTy(opt_did, impl_id) => { Def::SelfTy(opt_did.map(|did| did.tr(dcx)),
+                                                         impl_id.map(|id| dcx.tr_id(id))) }
           Def::Mod(did) => { Def::Mod(did.tr(dcx)) }
           Def::ForeignMod(did) => { Def::ForeignMod(did.tr(dcx)) }
           Def::Static(did, m) => { Def::Static(did.tr(dcx), m) }

src/librustc_resolve/lib.rs

@@ -1938,7 +1938,7 @@ impl<'a> Resolver<'a> {
                 // Resolve the self type.
                 this.visit_ty(self_type);
 
-                this.with_self_rib(Def::SelfTy(trait_id, Some((item_id, self_type.id))), |this| {
+                this.with_self_rib(Def::SelfTy(trait_id, Some(item_id)), |this| {
                     this.with_current_self_type(self_type, |this| {
                         for impl_item in impl_items {
                             this.resolve_visibility(&impl_item.vis);

src/librustc_typeck/astconv.rs

@@ -1272,7 +1272,7 @@ fn associated_path_def_to_ty<'tcx>(this: &AstConv<'tcx, 'tcx>,
     // Find the type of the associated item, and the trait where the associated
     // item is declared.
     let bound = match (&ty.sty, ty_path_def) {
-        (_, Def::SelfTy(Some(trait_did), Some((impl_id, _)))) => {
+        (_, Def::SelfTy(Some(trait_did), Some(impl_id))) => {
             // `Self` in an impl of a trait - we have a concrete self type and a
             // trait reference.
             let trait_ref = tcx.impl_trait_ref(tcx.map.local_def_id(impl_id)).unwrap();
@@ -1479,17 +1479,14 @@ fn base_def_to_ty<'tcx>(this: &AstConv<'tcx, 'tcx>,
             tcx.prohibit_type_params(base_segments);
             tcx.mk_param(space, index, name)
         }
-        Def::SelfTy(_, Some((_, self_ty_id))) => {
+        Def::SelfTy(_, Some(impl_id)) => {
             // Self in impl (we know the concrete type).
             tcx.prohibit_type_params(base_segments);
-            if let Some(&ty) = tcx.ast_ty_to_ty_cache.borrow().get(&self_ty_id) {
-                if let Some(free_substs) = this.get_free_substs() {
-                    ty.subst(tcx, free_substs)
-                } else {
-                    ty
-                }
+            let ty = tcx.node_id_to_type(impl_id);
+            if let Some(free_substs) = this.get_free_substs() {
+                ty.subst(tcx, free_substs)
             } else {
-                span_bug!(span, "self type has not been fully resolved")
+                ty
             }
         }
         Def::SelfTy(Some(_), None) => {
@@ -1585,12 +1582,7 @@ pub fn ast_ty_to_ty<'tcx>(this: &AstConv<'tcx, 'tcx>,
 
     let tcx = this.tcx();
 
-    if let Some(&ty) = tcx.ast_ty_to_ty_cache.borrow().get(&ast_ty.id) {
-        debug!("ast_ty_to_ty: id={:?} ty={:?} (cached)", ast_ty.id, ty);
-        return ty;
-    }
-
-    let typ = match ast_ty.node {
+    match ast_ty.node {
         hir::TyVec(ref ty) => {
             tcx.mk_slice(ast_ty_to_ty(this, rscope, &ty))
         }
@@ -1714,11 +1706,7 @@ pub fn ast_ty_to_ty<'tcx>(this: &AstConv<'tcx, 'tcx>,
             // handled specially and will not descend into this routine.
             this.ty_infer(None, None, None, ast_ty.span)
         }
-    };
-
-    debug!("ast_ty_to_ty: id={:?} ty={:?}", ast_ty.id, typ);
-    tcx.ast_ty_to_ty_cache.borrow_mut().insert(ast_ty.id, typ);
-    return typ;
+    }
 }
 
 pub fn ty_of_arg<'tcx>(this: &AstConv<'tcx, 'tcx>,

src/librustdoc/clean/mod.rs

@@ -2696,7 +2696,7 @@ fn register_def(cx: &DocContext, def: Def) -> DefId {
         Def::Static(i, _) => (i, TypeStatic),
         Def::Variant(i, _) => (i, TypeEnum),
         Def::SelfTy(Some(def_id), _) => (def_id, TypeTrait),
-        Def::SelfTy(_, Some((impl_id, _))) => return cx.map.local_def_id(impl_id),
+        Def::SelfTy(_, Some(impl_id)) => return cx.map.local_def_id(impl_id),
         _ => return def.def_id()
     };
     if did.is_local() { return did }