rustc: Remove HirId from queries

This'll allow us to reconstruct query parameters purely from the `DepNode`
they're associated with. Some queries could move straight to `HirId` but others
that don't always have a correspondance between `HirId` and `DefId` moved to
two-level maps where the query operates over a `DefIndex`, returning a map,
which is then keyed off `ItemLocalId`.

Closes #44414

Author: alexcrichton

src/librustc/dep_graph/dep_node.rs

@@ -60,7 +60,7 @@
 //! user of the `DepNode` API of having to know how to compute the expected
 //! fingerprint for a given set of node parameters.
 
-use hir::def_id::{CrateNum, DefId};
+use hir::def_id::{CrateNum, DefId, DefIndex};
 use hir::map::DefPathHash;
 use hir::{HirId, ItemLocalId};
 
@@ -528,8 +528,8 @@ define_dep_nodes!( <'tcx>
     [] ExternCrate(DefId),
     [] LintLevels,
     [] Specializes { impl1: DefId, impl2: DefId },
-    [] InScopeTraits(HirId),
-    [] ModuleExports(HirId),
+    [] InScopeTraits(DefIndex),
+    [] ModuleExports(DefId),
     [] IsSanitizerRuntime(CrateNum),
     [] IsProfilerRuntime(CrateNum),
     [] GetPanicStrategy(CrateNum),
@@ -551,15 +551,15 @@ define_dep_nodes!( <'tcx>
     [] NativeLibraryKind(DefId),
     [] LinkArgs,
 
-    [] NamedRegion(HirId),
-    [] IsLateBound(HirId),
-    [] ObjectLifetimeDefaults(HirId),
+    [] NamedRegion(DefIndex),
+    [] IsLateBound(DefIndex),
+    [] ObjectLifetimeDefaults(DefIndex),
 
     [] Visibility(DefId),
     [] DepKind(CrateNum),
     [] CrateName(CrateNum),
     [] ItemChildren(DefId),
-    [] ExternModStmtCnum(HirId),
+    [] ExternModStmtCnum(DefId),
     [] GetLangItems,
     [] DefinedLangItems(CrateNum),
     [] MissingLangItems(CrateNum),
@@ -570,8 +570,8 @@ define_dep_nodes!( <'tcx>
     [] UsedCrateSource(CrateNum),
     [] PostorderCnums,
 
-    [] Freevars(HirId),
-    [] MaybeUnusedTraitImport(HirId),
+    [] Freevars(DefId),
+    [] MaybeUnusedTraitImport(DefId),
     [] MaybeUnusedExternCrates,
     [] StabilityIndex,
     [] AllCrateNums,

src/librustc/hir/def.rs

@@ -9,7 +9,7 @@
 // except according to those terms.
 
 use hir::def_id::DefId;
-use util::nodemap::NodeMap;
+use util::nodemap::{NodeMap, DefIdMap};
 use syntax::ast;
 use syntax::ext::base::MacroKind;
 use syntax_pos::Span;
@@ -114,7 +114,7 @@ pub type DefMap = NodeMap<PathResolution>;
 
 /// This is the replacement export map. It maps a module to all of the exports
 /// within.
-pub type ExportMap = NodeMap<Vec<Export>>;
+pub type ExportMap = DefIdMap<Vec<Export>>;
 
 #[derive(Copy, Clone, Debug, RustcEncodable, RustcDecodable)]
 pub struct Export {

src/librustc/ich/hcx.rs

@@ -199,20 +199,19 @@ impl<'a, 'gcx, 'tcx> HashStable<StableHashingContext<'a, 'gcx, 'tcx>> for ast::N
     fn hash_stable<W: StableHasherResult>(&self,
                                           hcx: &mut StableHashingContext<'a, 'gcx, 'tcx>,
                                           hasher: &mut StableHasher<W>) {
+        let hir_id = hcx.tcx.hir.node_to_hir_id(*self);
         match hcx.node_id_hashing_mode {
             NodeIdHashingMode::Ignore => {
                 // Most NodeIds in the HIR can be ignored, but if there is a
                 // corresponding entry in the `trait_map` we need to hash that.
                 // Make sure we don't ignore too much by checking that there is
                 // no entry in a debug_assert!().
-                let hir_id = hcx.tcx.hir.node_to_hir_id(*self);
                 debug_assert!(hcx.tcx.in_scope_traits(hir_id).is_none());
             }
             NodeIdHashingMode::HashDefPath => {
-                hcx.tcx.hir.definitions().node_to_hir_id(*self).hash_stable(hcx, hasher);
+                hir_id.hash_stable(hcx, hasher);
             }
             NodeIdHashingMode::HashTraitsInScope => {
-                let hir_id = hcx.tcx.hir.node_to_hir_id(*self);
                 if let Some(traits) = hcx.tcx.in_scope_traits(hir_id) {
                     // The ordering of the candidates is not fixed. So we hash
                     // the def-ids and then sort them and hash the collection.

src/librustc/middle/stability.rs

@@ -612,8 +612,8 @@ impl<'a, 'tcx> Visitor<'tcx> for Checker<'a, 'tcx> {
                 // compiler-generated `extern crate` items have a dummy span.
                 if item.span == DUMMY_SP { return }
 
-                let hir_id = self.tcx.hir.node_to_hir_id(item.id);
-                let cnum = match self.tcx.extern_mod_stmt_cnum(hir_id) {
+                let def_id = self.tcx.hir.local_def_id(item.id);
+                let cnum = match self.tcx.extern_mod_stmt_cnum(def_id) {
                     Some(cnum) => cnum,
                     None => return,
                 };

src/librustc/ty/context.rs

@@ -14,9 +14,9 @@ use dep_graph::DepGraph;
 use errors::DiagnosticBuilder;
 use session::Session;
 use middle;
-use hir::{TraitCandidate, HirId};
+use hir::{TraitCandidate, HirId, ItemLocalId};
 use hir::def::{Def, Export};
-use hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
+use hir::def_id::{CrateNum, DefId, DefIndex, LOCAL_CRATE};
 use hir::map as hir_map;
 use hir::map::DefPathHash;
 use lint::{self, Lint};
@@ -816,10 +816,10 @@ pub struct GlobalCtxt<'tcx> {
 
     /// Map indicating what traits are in scope for places where this
     /// is relevant; generated by resolve.
-    trait_map: FxHashMap<HirId, Rc<Vec<TraitCandidate>>>,
+    trait_map: FxHashMap<DefIndex, Rc<FxHashMap<ItemLocalId, Rc<Vec<TraitCandidate>>>>>,
 
     /// Export map produced by name resolution.
-    export_map: FxHashMap<HirId, Rc<Vec<Export>>>,
+    export_map: FxHashMap<DefId, Rc<Vec<Export>>>,
 
     named_region_map: NamedRegionMap,
 
@@ -836,11 +836,11 @@ pub struct GlobalCtxt<'tcx> {
     // Records the free variables refrenced by every closure
     // expression. Do not track deps for this, just recompute it from
     // scratch every time.
-    freevars: FxHashMap<HirId, Rc<Vec<hir::Freevar>>>,
+    freevars: FxHashMap<DefId, Rc<Vec<hir::Freevar>>>,
 
-    maybe_unused_trait_imports: FxHashSet<HirId>,
+    maybe_unused_trait_imports: FxHashSet<DefId>,
 
-    maybe_unused_extern_crates: Vec<(HirId, Span)>,
+    maybe_unused_extern_crates: Vec<(DefId, Span)>,
 
     // Internal cache for metadata decoding. No need to track deps on this.
     pub rcache: RefCell<FxHashMap<ty::CReaderCacheKey, Ty<'tcx>>>,
@@ -1031,6 +1031,35 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             None
         };
 
+        let mut trait_map = FxHashMap();
+        for (k, v) in resolutions.trait_map {
+            let hir_id = hir.node_to_hir_id(k);
+            let map = trait_map.entry(hir_id.owner)
+                .or_insert_with(|| Rc::new(FxHashMap()));
+            Rc::get_mut(map).unwrap().insert(hir_id.local_id, Rc::new(v));
+        }
+        let mut defs = FxHashMap();
+        for (k, v) in named_region_map.defs {
+            let hir_id = hir.node_to_hir_id(k);
+            let map = defs.entry(hir_id.owner)
+                .or_insert_with(|| Rc::new(FxHashMap()));
+            Rc::get_mut(map).unwrap().insert(hir_id.local_id, v);
+        }
+        let mut late_bound = FxHashMap();
+        for k in named_region_map.late_bound {
+            let hir_id = hir.node_to_hir_id(k);
+            let map = late_bound.entry(hir_id.owner)
+                .or_insert_with(|| Rc::new(FxHashSet()));
+            Rc::get_mut(map).unwrap().insert(hir_id.local_id);
+        }
+        let mut object_lifetime_defaults = FxHashMap();
+        for (k, v) in named_region_map.object_lifetime_defaults {
+            let hir_id = hir.node_to_hir_id(k);
+            let map = object_lifetime_defaults.entry(hir_id.owner)
+                .or_insert_with(|| Rc::new(FxHashMap()));
+            Rc::get_mut(map).unwrap().insert(hir_id.local_id, Rc::new(v));
+        }
+
         tls::enter_global(GlobalCtxt {
             sess: s,
             trans_trait_caches: traits::trans::TransTraitCaches::new(dep_graph.clone()),
@@ -1039,40 +1068,26 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
             dep_graph: dep_graph.clone(),
             types: common_types,
             named_region_map: NamedRegionMap {
-                defs:
-                    named_region_map.defs
-                        .into_iter()
-                        .map(|(k, v)| (hir.node_to_hir_id(k), v))
-                        .collect(),
-                late_bound:
-                    named_region_map.late_bound
-                        .into_iter()
-                        .map(|k| hir.node_to_hir_id(k))
-                        .collect(),
-                object_lifetime_defaults:
-                    named_region_map.object_lifetime_defaults
-                        .into_iter()
-                        .map(|(k, v)| (hir.node_to_hir_id(k), Rc::new(v)))
-                        .collect(),
+                defs,
+                late_bound,
+                object_lifetime_defaults,
             },
-            trait_map: resolutions.trait_map.into_iter().map(|(k, v)| {
-                (hir.node_to_hir_id(k), Rc::new(v))
-            }).collect(),
+            trait_map,
             export_map: resolutions.export_map.into_iter().map(|(k, v)| {
-                (hir.node_to_hir_id(k), Rc::new(v))
+                (k, Rc::new(v))
             }).collect(),
             freevars: resolutions.freevars.into_iter().map(|(k, v)| {
-                (hir.node_to_hir_id(k), Rc::new(v))
+                (hir.local_def_id(k), Rc::new(v))
             }).collect(),
             maybe_unused_trait_imports:
                 resolutions.maybe_unused_trait_imports
                     .into_iter()
-                    .map(|id| hir.node_to_hir_id(id))
+                    .map(|id| hir.local_def_id(id))
                     .collect(),
             maybe_unused_extern_crates:
                 resolutions.maybe_unused_extern_crates
                     .into_iter()
-                    .map(|(id, sp)| (hir.node_to_hir_id(id), sp))
+                    .map(|(id, sp)| (hir.local_def_id(id), sp))
                     .collect(),
             hir,
             def_path_hash_to_def_id,
@@ -1966,6 +1981,29 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         let (level, src) = self.lint_level_at_node(lint, id);
         lint::struct_lint_level(self.sess, lint, level, src, None, msg)
     }
+
+    pub fn in_scope_traits(self, id: HirId) -> Option<Rc<Vec<TraitCandidate>>> {
+        self.in_scope_traits_map(id.owner)
+            .and_then(|map| map.get(&id.local_id).cloned())
+    }
+
+    pub fn named_region(self, id: HirId) -> Option<resolve_lifetime::Region> {
+        self.named_region_map(id.owner)
+            .and_then(|map| map.get(&id.local_id).cloned())
+    }
+
+    pub fn is_late_bound(self, id: HirId) -> bool {
+        self.is_late_bound_map(id.owner)
+            .map(|set| set.contains(&id.local_id))
+            .unwrap_or(false)
+    }
+
+    pub fn object_lifetime_defaults(self, id: HirId)
+        -> Option<Rc<Vec<ObjectLifetimeDefault>>>
+    {
+        self.object_lifetime_defaults_map(id.owner)
+            .and_then(|map| map.get(&id.local_id).cloned())
+    }
 }
 
 pub trait InternAs<T: ?Sized, R> {
@@ -2013,20 +2051,24 @@ impl<T, R, E> InternIteratorElement<T, R> for Result<T, E> {
 }
 
 struct NamedRegionMap {
-    defs: FxHashMap<HirId, resolve_lifetime::Region>,
-    late_bound: FxHashSet<HirId>,
-    object_lifetime_defaults: FxHashMap<HirId, Rc<Vec<ObjectLifetimeDefault>>>,
+    defs: FxHashMap<DefIndex, Rc<FxHashMap<ItemLocalId, resolve_lifetime::Region>>>,
+    late_bound: FxHashMap<DefIndex, Rc<FxHashSet<ItemLocalId>>>,
+    object_lifetime_defaults:
+        FxHashMap<
+            DefIndex,
+            Rc<FxHashMap<ItemLocalId, Rc<Vec<ObjectLifetimeDefault>>>>,
+        >,
 }
 
 pub fn provide(providers: &mut ty::maps::Providers) {
     // FIXME(#44234) - almost all of these queries have no sub-queries and
     // therefore no actual inputs, they're just reading tables calculated in
     // resolve! Does this work? Unsure! That's what the issue is about
-    providers.in_scope_traits = |tcx, id| tcx.gcx.trait_map.get(&id).cloned();
+    providers.in_scope_traits_map = |tcx, id| tcx.gcx.trait_map.get(&id).cloned();
     providers.module_exports = |tcx, id| tcx.gcx.export_map.get(&id).cloned();
-    providers.named_region = |tcx, id| tcx.gcx.named_region_map.defs.get(&id).cloned();
-    providers.is_late_bound = |tcx, id| tcx.gcx.named_region_map.late_bound.contains(&id);
-    providers.object_lifetime_defaults = |tcx, id| {
+    providers.named_region_map = |tcx, id| tcx.gcx.named_region_map.defs.get(&id).cloned();
+    providers.is_late_bound_map = |tcx, id| tcx.gcx.named_region_map.late_bound.get(&id).cloned();
+    providers.object_lifetime_defaults_map = |tcx, id| {
         tcx.gcx.named_region_map.object_lifetime_defaults.get(&id).cloned()
     };
     providers.crate_name = |tcx, id| {