diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/rustc_ast_lowering/src/lib.rs | 97 |
1 files changed, 34 insertions, 63 deletions
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs index 66bcd698e6a..e93db721fcf 100644 --- a/compiler/rustc_ast_lowering/src/lib.rs +++ b/compiler/rustc_ast_lowering/src/lib.rs @@ -80,8 +80,6 @@ mod item; mod pat; mod path; -const HIR_ID_COUNTER_LOCKED: u32 = 0xFFFFFFFF; - rustc_hir::arena_types!(rustc_arena::declare_arena, 'tcx); struct LoweringContext<'a, 'hir: 'a> { @@ -151,7 +149,7 @@ struct LoweringContext<'a, 'hir: 'a> { in_scope_lifetimes: Vec<ParamName>, current_hir_id_owner: (LocalDefId, u32), - item_local_id_counters: NodeMap<u32>, + item_local_id_counters: IndexVec<LocalDefId, u32>, node_id_to_hir_id: IndexVec<NodeId, Option<hir::HirId>>, allow_try_trait: Option<Lrc<[Symbol]>>, @@ -488,15 +486,6 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { id } - fn allocate_hir_id_counter(&mut self, owner: NodeId) -> LocalDefId { - // Set up the counter if needed. - self.item_local_id_counters.entry(owner).or_insert(0); - // Always allocate the first `HirId` for the owner itself. - let lowered = self.lower_node_id_with_owner(owner, owner); - debug_assert_eq!(lowered.local_id.as_u32(), 0); - lowered.owner - } - fn create_stable_hashing_context(&self) -> LoweringHasher<'_> { LoweringHasher { source_map: CachingSourceMapView::new(self.sess.source_map()), @@ -504,36 +493,34 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { } } - fn lower_node_id_generic( - &mut self, - ast_node_id: NodeId, - alloc_hir_id: impl FnOnce(&mut Self) -> hir::HirId, - ) -> hir::HirId { - assert_ne!(ast_node_id, DUMMY_NODE_ID); - - let min_size = ast_node_id.as_usize() + 1; - - if min_size > self.node_id_to_hir_id.len() { - self.node_id_to_hir_id.resize(min_size, None); - } + fn allocate_hir_id_counter(&mut self, owner: NodeId) -> LocalDefId { + // Set up the counter if needed. + let def_id = self.resolver.local_def_id(owner); - if let Some(existing_hir_id) = self.node_id_to_hir_id[ast_node_id] { - existing_hir_id + // Always allocate the first `HirId` for the owner itself. + self.node_id_to_hir_id.ensure_contains_elem(owner, || None); + if let Some(_lowered) = self.node_id_to_hir_id[owner] { + debug_assert_eq!(_lowered.owner, def_id); + debug_assert_eq!(_lowered.local_id.as_u32(), 0); } else { - // Generate a new `HirId`. - let hir_id = alloc_hir_id(self); - self.node_id_to_hir_id[ast_node_id] = Some(hir_id); + self.item_local_id_counters.ensure_contains_elem(def_id, || 0); + let local_id_counter = &mut self.item_local_id_counters[def_id]; + let local_id = *local_id_counter; - hir_id + // We want to be sure not to modify the counter in the map while it + // is also on the stack. Otherwise we'll get lost updates when writing + // back from the stack to the map. + debug_assert_eq!(local_id, 0); + + *local_id_counter += 1; + self.node_id_to_hir_id[owner] = Some(hir::HirId::make_owner(def_id)); } + def_id } fn with_hir_id_owner<T>(&mut self, owner: NodeId, f: impl FnOnce(&mut Self) -> T) -> T { - let counter = self - .item_local_id_counters - .insert(owner, HIR_ID_COUNTER_LOCKED) - .unwrap_or_else(|| panic!("no `item_local_id_counters` entry for {:?}", owner)); let def_id = self.resolver.local_def_id(owner); + let counter = self.item_local_id_counters[def_id]; let old_owner = std::mem::replace(&mut self.current_hir_id_owner, (def_id, counter)); let ret = f(self); let (new_def_id, new_counter) = @@ -542,8 +529,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { debug_assert!(def_id == new_def_id); debug_assert!(new_counter >= counter); - let prev = self.item_local_id_counters.insert(owner, new_counter).unwrap(); - debug_assert!(prev == HIR_ID_COUNTER_LOCKED); + self.item_local_id_counters[def_id] = new_counter; ret } @@ -554,35 +540,20 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { /// `HirIdValidator` later on, which makes sure that all `NodeId`s got mapped /// properly. Calling the method twice with the same `NodeId` is fine though. fn lower_node_id(&mut self, ast_node_id: NodeId) -> hir::HirId { - self.lower_node_id_generic(ast_node_id, |this| { - let &mut (owner, ref mut local_id_counter) = &mut this.current_hir_id_owner; - let local_id = *local_id_counter; - *local_id_counter += 1; - hir::HirId { owner, local_id: hir::ItemLocalId::from_u32(local_id) } - }) - } + assert_ne!(ast_node_id, DUMMY_NODE_ID); - fn lower_node_id_with_owner(&mut self, ast_node_id: NodeId, owner: NodeId) -> hir::HirId { - self.lower_node_id_generic(ast_node_id, |this| { - let local_id_counter = this - .item_local_id_counters - .get_mut(&owner) - .expect("called `lower_node_id_with_owner` before `allocate_hir_id_counter`"); + self.node_id_to_hir_id.ensure_contains_elem(ast_node_id, || None); + if let Some(existing_hir_id) = self.node_id_to_hir_id[ast_node_id] { + existing_hir_id + } else { + // Generate a new `HirId`. + let &mut (owner, ref mut local_id_counter) = &mut self.current_hir_id_owner; let local_id = *local_id_counter; - - // We want to be sure not to modify the counter in the map while it - // is also on the stack. Otherwise we'll get lost updates when writing - // back from the stack to the map. - debug_assert!(local_id != HIR_ID_COUNTER_LOCKED); - *local_id_counter += 1; - let owner = this.resolver.opt_local_def_id(owner).expect( - "you forgot to call `create_def` or are lowering node-IDs \ - that do not belong to the current owner", - ); - - hir::HirId { owner, local_id: hir::ItemLocalId::from_u32(local_id) } - }) + let hir_id = hir::HirId { owner, local_id: hir::ItemLocalId::from_u32(local_id) }; + self.node_id_to_hir_id[ast_node_id] = Some(hir_id); + hir_id + } } fn next_id(&mut self) -> hir::HirId { @@ -592,7 +563,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> { fn lower_res(&mut self, res: Res<NodeId>) -> Res { res.map_id(|id| { - self.lower_node_id_generic(id, |_| { + self.node_id_to_hir_id.get(id).copied().flatten().unwrap_or_else(|| { panic!("expected `NodeId` to be lowered already for res {:#?}", res); }) }) |