resolve: Pre-intern builtin name bindings

compiler/rustc_resolve/src/ident.rs

@@ -1,7 +1,5 @@
 use rustc_ast::{self as ast, NodeId};
-use rustc_feature::is_builtin_attr_name;
 use rustc_hir::def::{DefKind, Namespace, NonMacroAttrKind, PartialRes, PerNS};
-use rustc_hir::PrimTy;
 use rustc_middle::bug;
 use rustc_middle::ty;
 use rustc_session::lint::builtin::PROC_MACRO_DERIVE_RESOLUTION_FALLBACK;
@@ -9,7 +7,7 @@
 use rustc_span::def_id::LocalDefId;
 use rustc_span::hygiene::{ExpnId, ExpnKind, LocalExpnId, MacroKind, SyntaxContext};
 use rustc_span::symbol::{kw, Ident};
-use rustc_span::{Span, DUMMY_SP};
+use rustc_span::Span;
 
 use crate::errors::{ParamKindInEnumDiscriminant, ParamKindInNonTrivialAnonConst};
 use crate::late::{
@@ -562,17 +560,10 @@ struct Flags: u8 {
                             )),
                         }
                     }
-                    Scope::BuiltinAttrs => {
-                        if is_builtin_attr_name(ident.name) {
-                            ok(
-                                Res::NonMacroAttr(NonMacroAttrKind::Builtin(ident.name)),
-                                DUMMY_SP,
-                                this.arenas,
-                            )
-                        } else {
-                            Err(Determinacy::Determined)
-                        }
-                    }
+                    Scope::BuiltinAttrs => match this.builtin_attrs_bindings.get(&ident.name) {
+                        Some(binding) => Ok((*binding, Flags::empty())),
+                        None => Err(Determinacy::Determined),
+                    },
                     Scope::ExternPrelude => {
                         match this.extern_prelude_get(ident, finalize.is_some()) {
                             Some(binding) => Ok((binding, Flags::empty())),
@@ -603,8 +594,8 @@ struct Flags: u8 {
                         }
                         result
                     }
-                    Scope::BuiltinTypes => match PrimTy::from_name(ident.name) {
-                        Some(prim_ty) => ok(Res::PrimTy(prim_ty), DUMMY_SP, this.arenas),
+                    Scope::BuiltinTypes => match this.builtin_types_bindings.get(&ident.name) {
+                        Some(binding) => Ok((*binding, Flags::empty())),
                         None => Err(Determinacy::Determined),
                     },
                 };

compiler/rustc_resolve/src/lib.rs

@@ -39,13 +39,15 @@
     Applicability, DiagnosticBuilder, DiagnosticMessage, ErrorGuaranteed, SubdiagnosticMessage,
 };
 use rustc_expand::base::{DeriveResolutions, SyntaxExtension, SyntaxExtensionKind};
+use rustc_feature::BUILTIN_ATTRIBUTES;
 use rustc_fluent_macro::fluent_messages;
 use rustc_hir::def::Namespace::{self, *};
+use rustc_hir::def::NonMacroAttrKind;
 use rustc_hir::def::{self, CtorOf, DefKind, DocLinkResMap, LifetimeRes, PartialRes, PerNS};
 use rustc_hir::def_id::{CrateNum, DefId, LocalDefId, LocalDefIdMap, LocalDefIdSet};
 use rustc_hir::def_id::{CRATE_DEF_ID, LOCAL_CRATE};
 use rustc_hir::definitions::DefPathData;
-use rustc_hir::TraitCandidate;
+use rustc_hir::{PrimTy, TraitCandidate};
 use rustc_index::IndexVec;
 use rustc_metadata::creader::{CStore, CrateLoader};
 use rustc_middle::metadata::ModChild;
@@ -996,6 +998,8 @@ pub struct Resolver<'a, 'tcx> {
 
     arenas: &'a ResolverArenas<'a>,
     dummy_binding: NameBinding<'a>,
+    builtin_types_bindings: FxHashMap<Symbol, NameBinding<'a>>,
+    builtin_attrs_bindings: FxHashMap<Symbol, NameBinding<'a>>,
 
     used_extern_options: FxHashSet<Symbol>,
     macro_names: FxHashSet<Ident>,
@@ -1283,6 +1287,7 @@ pub fn new(
         let registered_tools = tcx.registered_tools(());
 
         let features = tcx.features();
+        let pub_vis = ty::Visibility::<DefId>::Public;
 
         let mut resolver = Resolver {
             tcx,
@@ -1330,14 +1335,24 @@ pub fn new(
             macro_expanded_macro_export_errors: BTreeSet::new(),
 
             arenas,
-            dummy_binding: arenas.alloc_name_binding(NameBindingData {
-                kind: NameBindingKind::Res(Res::Err),
-                ambiguity: None,
-                warn_ambiguity: false,
-                expansion: LocalExpnId::ROOT,
-                span: DUMMY_SP,
-                vis: ty::Visibility::Public,
-            }),
+            dummy_binding: (Res::Err, pub_vis, DUMMY_SP, LocalExpnId::ROOT).to_name_binding(arenas),
+            builtin_types_bindings: PrimTy::ALL
+                .iter()
+                .map(|prim_ty| {
+                    let binding = (Res::PrimTy(*prim_ty), pub_vis, DUMMY_SP, LocalExpnId::ROOT)
+                        .to_name_binding(arenas);
+                    (prim_ty.name(), binding)
+                })
+                .collect(),
+            builtin_attrs_bindings: BUILTIN_ATTRIBUTES
+                .iter()
+                .map(|builtin_attr| {
+                    let res = Res::NonMacroAttr(NonMacroAttrKind::Builtin(builtin_attr.name));
+                    let binding =
+                        (res, pub_vis, DUMMY_SP, LocalExpnId::ROOT).to_name_binding(arenas);
+                    (builtin_attr.name, binding)
+                })
+                .collect(),
 
             used_extern_options: Default::default(),
             macro_names: FxHashSet::default(),