Rollup merge of #157379 - oli-obk:more-per-owner, r=petrochenkov

Some more simple per-owner resolver changes

Fairly straight forward ones. The remaining data structures are either more involved or blocked on other changes waiting to happen.

I especially like how the import res map stops being a map, as there can only be one import res per owner (each import is its own owner)

r? @petrochenkov

Author: jhpratt

compiler/rustc_ast_lowering/src/lib.rs

@@ -126,7 +126,7 @@ struct LoweringContext<'a, 'hir> {
     is_in_dyn_type: bool,
 
     current_hir_id_owner: hir::OwnerId,
-    owner: &'a PerOwnerResolverData,
+    owner: &'a PerOwnerResolverData<'hir>,
     item_local_id_counter: hir::ItemLocalId,
     trait_map: ItemLocalMap<&'hir [TraitCandidate<'hir>]>,
 
@@ -288,11 +288,6 @@ impl<'tcx> ResolverAstLowering<'tcx> {
         .map(|fn_indexes| fn_indexes.iter().map(|(num, _)| *num).collect())
     }
 
-    /// Obtains per-namespace resolutions for `use` statement with the given `NodeId`.
-    fn get_import_res(&self, id: NodeId) -> PerNS<Option<Res<NodeId>>> {
-        self.import_res_map.get(&id).copied().unwrap_or_default()
-    }
-
     /// Obtain the list of lifetimes parameters to add to an item.
     ///
     /// Extra lifetime parameters should only be added in places that can appear
@@ -810,8 +805,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
             self.children.push((def_id, hir::MaybeOwner::NonOwner(hir_id)));
         }
 
-        if let Some(traits) = self.resolver.trait_map.get(&ast_node_id) {
-            self.trait_map.insert(hir_id.local_id, &traits[..]);
+        if let Some(traits) = self.owner.trait_map.get(&ast_node_id) {
+            self.trait_map.insert(hir_id.local_id, *traits);
         }
 
         // Check whether the same `NodeId` is lowered more than once.
@@ -856,8 +851,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
     }
 
     fn lower_import_res(&mut self, id: NodeId, span: Span) -> PerNS<Option<Res>> {
-        let per_ns = self.resolver.get_import_res(id);
-        let per_ns = per_ns.map(|res| res.map(|res| self.lower_res(res)));
+        debug_assert_eq!(id, self.owner.id);
+        let per_ns = self.owner.import_res.map(|res| res.map(|res| self.lower_res(res)));
         if per_ns.is_empty() {
             // Propagate the error to all namespaces, just to be sure.
             self.dcx().span_delayed_bug(span, "no resolution for an import");

compiler/rustc_hir/src/def.rs

@@ -717,7 +717,8 @@ impl IntoDiagArg for Namespace {
 }
 
 /// Just a helper ‒ separate structure for each namespace.
-#[derive(Copy, Clone, Default, Debug, StableHash)]
+#[derive(Copy, Clone, Debug, StableHash)]
+#[derive_const(Default)]
 pub struct PerNS<T> {
     pub value_ns: T,
     pub type_ns: T,

compiler/rustc_middle/src/ty/mod.rs

@@ -27,9 +27,9 @@ pub use intrinsic::IntrinsicDef;
 use rustc_abi::{
     Align, FieldIdx, Integer, IntegerType, ReprFlags, ReprOptions, ScalableElt, VariantIdx,
 };
-use rustc_ast as ast;
 use rustc_ast::expand::typetree::{FncTree, Kind, Type, TypeTree};
 use rustc_ast::node_id::NodeMap;
+use rustc_ast::{self as ast};
 pub use rustc_ast_ir::{Movability, Mutability, try_visit};
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_data_structures::intern::Interned;
@@ -204,7 +204,7 @@ pub struct ResolverGlobalCtxt {
 }
 
 #[derive(Debug)]
-pub struct PerOwnerResolverData {
+pub struct PerOwnerResolverData<'tcx> {
     pub node_id_to_def_id: NodeMap<LocalDefId> = Default::default(),
     /// Whether lifetime elision was successful.
     pub lifetime_elision_allowed: bool = false,
@@ -214,14 +214,19 @@ pub struct PerOwnerResolverData {
     /// Resolutions for lifetimes.
     pub lifetimes_res_map: NodeMap<LifetimeRes> = Default::default(),
 
+    pub trait_map: NodeMap<&'tcx [hir::TraitCandidate<'tcx>]> = Default::default(),
+
+    /// Resolution for import nodes, which have multiple resolutions in different namespaces.
+    pub import_res: hir::def::PerNS<Option<Res<ast::NodeId>>> = Default::default(),
+
     /// The id of the owner
     pub id: ast::NodeId,
     /// The `DefId` of the owner, can't be found in `node_id_to_def_id`.
     pub def_id: LocalDefId,
 }
 
-impl PerOwnerResolverData {
-    pub fn new(id: ast::NodeId, def_id: LocalDefId) -> PerOwnerResolverData {
+impl<'tcx> PerOwnerResolverData<'tcx> {
+    pub fn new(id: ast::NodeId, def_id: LocalDefId) -> PerOwnerResolverData<'tcx> {
         PerOwnerResolverData { id, def_id, .. }
     }
 
@@ -242,16 +247,12 @@ impl PerOwnerResolverData {
 pub struct ResolverAstLowering<'tcx> {
     /// Resolutions for nodes that have a single resolution.
     pub partial_res_map: NodeMap<hir::def::PartialRes>,
-    /// Resolutions for import nodes, which have multiple resolutions in different namespaces.
-    pub import_res_map: NodeMap<hir::def::PerNS<Option<Res<ast::NodeId>>>>,
     /// Lifetime parameters that lowering will have to introduce.
     pub extra_lifetime_params_map: NodeMap<Vec<(Ident, ast::NodeId, MissingLifetimeKind)>>,
 
     pub next_node_id: ast::NodeId,
 
-    pub owners: NodeMap<PerOwnerResolverData>,
-
-    pub trait_map: NodeMap<&'tcx [hir::TraitCandidate<'tcx>]>,
+    pub owners: NodeMap<PerOwnerResolverData<'tcx>>,
 
     /// Lints that were emitted by the resolver and early lints.
     pub lint_buffer: Steal<LintBuffer>,

compiler/rustc_resolve/src/check_unused.rs

@@ -134,12 +134,10 @@ impl<'a, 'ra, 'tcx> UnusedImportCheckVisitor<'a, 'ra, 'tcx> {
         match item.kind {
             ast::UseTreeKind::Simple(Some(ident)) => {
                 if ident.name == kw::Underscore
-                    && !self.r.import_res_map.get(&id).is_some_and(|per_ns| {
-                        matches!(
-                            per_ns.type_ns,
-                            Some(Res::Def(DefKind::Trait | DefKind::TraitAlias, _))
-                        )
-                    })
+                    && !matches!(
+                        self.r.owners[&id].import_res.type_ns,
+                        Some(Res::Def(DefKind::Trait | DefKind::TraitAlias, _))
+                    )
                 {
                     self.unused_import(self.base_id).add(id);
                 }

compiler/rustc_resolve/src/imports.rs

@@ -1642,7 +1642,7 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
         // purposes it's good enough to just favor one over the other.
         self.per_ns(|this, ns| {
             if let Some(binding) = bindings[ns].get().decl().map(|b| b.import_source()) {
-                this.import_res_map.entry(import_id).or_default()[ns] = Some(binding.res());
+                this.owners.get_mut(&import_id).unwrap().import_res[ns] = Some(binding.res());
             }
         });
 

compiler/rustc_resolve/src/late.rs

@@ -5388,7 +5388,7 @@ impl<'a, 'ast, 'ra, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {
             ident.span,
             Some((ident.name, ValueNS)),
         );
-        self.r.trait_map.insert(node_id, traits);
+        self.r.current_owner.trait_map.insert(node_id, traits);
     }
 
     fn resolve_and_cache_rustdoc_path(&mut self, path_str: &str, ns: Namespace) -> Option<Res> {

compiler/rustc_resolve/src/lib.rs

@@ -1364,8 +1364,6 @@ pub struct Resolver<'ra, 'tcx> {
 
     /// Resolutions for nodes that have a single resolution.
     partial_res_map: NodeMap<PartialRes> = Default::default(),
-    /// Resolutions for import nodes, which have multiple resolutions in different namespaces.
-    import_res_map: NodeMap<PerNS<Option<Res>>> = Default::default(),
     /// An import will be inserted into this map if it has been used.
     import_use_map: FxHashMap<Import<'ra>, Used> = default::fx_hash_map(),
     /// Lifetime parameters that lowering will have to introduce.
@@ -1375,7 +1373,6 @@ pub struct Resolver<'ra, 'tcx> {
     extern_crate_map: UnordMap<LocalDefId, CrateNum> = Default::default(),
     module_children: LocalDefIdMap<Vec<ModChild>> = Default::default(),
     ambig_module_children: LocalDefIdMap<Vec<AmbigModChild>> = Default::default(),
-    trait_map: NodeMap<&'tcx [TraitCandidate<'tcx>]> = Default::default(),
 
     /// A map from nodes to anonymous modules.
     /// Anonymous modules are pseudo-modules that are implicitly created around items
@@ -1490,10 +1487,10 @@ pub struct Resolver<'ra, 'tcx> {
     next_node_id: NodeId = CRATE_NODE_ID,
 
     /// Preserves per owner data once the owner is finished resolving.
-    owners: NodeMap<PerOwnerResolverData>,
+    owners: NodeMap<PerOwnerResolverData<'tcx>>,
 
     /// An entry of `owners` that gets taken out and reinserted whenever an owner is handled.
-    current_owner: PerOwnerResolverData,
+    current_owner: PerOwnerResolverData<'tcx>,
 
     disambiguators: LocalDefIdMap<PerParentDisambiguatorState>,
 
@@ -1997,11 +1994,9 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
         };
         let ast_lowering = ty::ResolverAstLowering {
             partial_res_map: self.partial_res_map,
-            import_res_map: self.import_res_map,
             extra_lifetime_params_map: self.extra_lifetime_params_map,
             next_node_id: self.next_node_id,
             owners: self.owners,
-            trait_map: self.trait_map,
             lint_buffer: Steal::new(self.lint_buffer),
             delegation_infos: self.delegation_infos,
             disambiguators,
@@ -2658,7 +2653,7 @@ fn with_owner<'ra, 'tcx, R: AsMut<Resolver<'ra, 'tcx>>, T>(
 fn with_owner_tables<'ra, 'tcx, R: AsMut<Resolver<'ra, 'tcx>>, T>(
     this: &mut R,
     owner: NodeId,
-    tables: PerOwnerResolverData,
+    tables: PerOwnerResolverData<'tcx>,
     work: impl FnOnce(&mut R) -> T,
 ) -> T {
     debug_assert!(!this.as_mut().owners.contains_key(&owner));