Use LocalDefIdSet/Map instead of FxHashSet/Map for live_symbols_and_ignored_derived_traits query.

compiler/rustc_middle/src/query/mod.rs

@@ -899,8 +899,8 @@
     /// The second return value maps from ADTs to ignored derived traits (e.g. Debug and Clone) and
     /// their respective impl (i.e., part of the derive macro)
     query live_symbols_and_ignored_derived_traits(_: ()) -> &'tcx (
-        FxHashSet<LocalDefId>,
+        LocalDefIdSet,
-        FxHashMap<LocalDefId, Vec<(DefId, DefId)>>
+        LocalDefIdMap<Vec<(DefId, DefId)>>
     ) {
         arena_cache
         desc { "finding live symbols in crate" }

compiler/rustc_middle/src/ty/query.rs

@@ -50,7 +50,9 @@
 use rustc_errors::ErrorGuaranteed;
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, DocLinkResMap};
-use rustc_hir::def_id::{CrateNum, DefId, DefIdMap, DefIdSet, LocalDefId, LocalDefIdSet};
+use rustc_hir::def_id::{
+    CrateNum, DefId, DefIdMap, DefIdSet, LocalDefId, LocalDefIdMap, LocalDefIdSet,
+};
 use rustc_hir::hir_id::OwnerId;
 use rustc_hir::lang_items::{LangItem, LanguageItems};
 use rustc_hir::{Crate, ItemLocalId, TraitCandidate};

compiler/rustc_passes/src/dead.rs

@@ -2,8 +2,8 @@
 // closely. The idea is that all reachable symbols are live, codes called
 // from live codes are live, and everything else is dead.
 
+use hir::def_id::{LocalDefIdMap, LocalDefIdSet};
 use itertools::Itertools;
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::MultiSpan;
 use rustc_hir as hir;
 use rustc_hir::def::{CtorOf, DefKind, Res};
@@ -45,17 +45,17 @@ struct MarkSymbolVisitor<'tcx> {
     worklist: Vec<LocalDefId>,
     tcx: TyCtxt<'tcx>,
     maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
-    live_symbols: FxHashSet<LocalDefId>,
+    live_symbols: LocalDefIdSet,
     repr_has_repr_c: bool,
     repr_has_repr_simd: bool,
     in_pat: bool,
     ignore_variant_stack: Vec<DefId>,
     // maps from tuple struct constructors to tuple struct items
-    struct_constructors: FxHashMap<LocalDefId, LocalDefId>,
+    struct_constructors: LocalDefIdMap<LocalDefId>,
     // maps from ADTs to ignored derived traits (e.g. Debug and Clone)
     // and the span of their respective impl (i.e., part of the derive
     // macro)
-    ignored_derived_traits: FxHashMap<LocalDefId, Vec<(DefId, DefId)>>,
+    ignored_derived_traits: LocalDefIdMap<Vec<(DefId, DefId)>>,
 }
 
 impl<'tcx> MarkSymbolVisitor<'tcx> {
@@ -237,7 +237,7 @@ fn handle_tuple_field_pattern_match(
     }
 
     fn mark_live_symbols(&mut self) {
-        let mut scanned = FxHashSet::default();
+        let mut scanned = LocalDefIdSet::default();
         while let Some(id) = self.worklist.pop() {
             if !scanned.insert(id) {
                 continue;
@@ -371,7 +371,7 @@ fn visit_variant_data(&mut self, def: &'tcx hir::VariantData<'tcx>) {
             }
             if tcx.visibility(def_id).is_public() { Some(def_id) } else { None }
         });
-        self.live_symbols.extend(live_fields);
+        Extend::extend(&mut self.live_symbols, live_fields);
 
         intravisit::walk_struct_def(self, def);
     }
@@ -506,7 +506,7 @@ fn has_used_like_attr(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool {
 fn check_item<'tcx>(
     tcx: TyCtxt<'tcx>,
     worklist: &mut Vec<LocalDefId>,
-    struct_constructors: &mut FxHashMap<LocalDefId, LocalDefId>,
+    struct_constructors: &mut LocalDefIdMap<LocalDefId>,
     id: hir::ItemId,
 ) {
     let allow_dead_code = has_allow_dead_code_or_lang_attr(tcx, id.owner_id.def_id);
@@ -583,9 +583,7 @@ fn check_foreign_item(tcx: TyCtxt<'_>, worklist: &mut Vec<LocalDefId>, id: hir::
     }
 }
 
-fn create_and_seed_worklist(
+fn create_and_seed_worklist(tcx: TyCtxt<'_>) -> (Vec<LocalDefId>, LocalDefIdMap<LocalDefId>) {
-    tcx: TyCtxt<'_>,
-) -> (Vec<LocalDefId>, FxHashMap<LocalDefId, LocalDefId>) {
     let effective_visibilities = &tcx.effective_visibilities(());
     // see `MarkSymbolVisitor::struct_constructors`
     let mut struct_constructors = Default::default();
@@ -617,7 +615,7 @@ fn create_and_seed_worklist(
 fn live_symbols_and_ignored_derived_traits(
     tcx: TyCtxt<'_>,
     (): (),
-) -> (FxHashSet<LocalDefId>, FxHashMap<LocalDefId, Vec<(DefId, DefId)>>) {
+) -> (LocalDefIdSet, LocalDefIdMap<Vec<(DefId, DefId)>>) {
     let (worklist, struct_constructors) = create_and_seed_worklist(tcx);
     let mut symbol_visitor = MarkSymbolVisitor {
         worklist,
@@ -629,7 +627,7 @@ fn live_symbols_and_ignored_derived_traits(
         in_pat: false,
         ignore_variant_stack: vec![],
         struct_constructors,
-        ignored_derived_traits: FxHashMap::default(),
+        ignored_derived_traits: Default::default(),
     };
     symbol_visitor.mark_live_symbols();
     (symbol_visitor.live_symbols, symbol_visitor.ignored_derived_traits)
@@ -643,8 +641,8 @@ struct DeadVariant {
 
 struct DeadVisitor<'tcx> {
     tcx: TyCtxt<'tcx>,
-    live_symbols: &'tcx FxHashSet<LocalDefId>,
+    live_symbols: &'tcx LocalDefIdSet,
-    ignored_derived_traits: &'tcx FxHashMap<LocalDefId, Vec<(DefId, DefId)>>,
+    ignored_derived_traits: &'tcx LocalDefIdMap<Vec<(DefId, DefId)>>,
 }
 
 enum ShouldWarnAboutField {