18 files changed, 241 insertions, 370 deletions

diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index 078bd8609..731cc1fff 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -11,7 +11,7 @@ use hir_def::{
     body::scope::ExprScopes,
     builtin_type::BuiltinType,
     type_ref::{Mutability, TypeRef},
-    CrateModuleId, LocalEnumVariantId, LocalStructFieldId, ModuleId, UnionId,
+    CrateModuleId, ImplId, LocalEnumVariantId, LocalStructFieldId, ModuleId, UnionId,
 };
 use hir_expand::{
     diagnostics::DiagnosticSink,
@@ -29,7 +29,6 @@ use crate::{
         AstItemDef, ConstId, EnumId, FunctionId, MacroDefId, StaticId, StructId, TraitId,
         TypeAliasId,
     },
-    impl_block::ImplBlock,
     resolve::{Resolver, Scope, TypeNs},
     traits::TraitData,
     ty::{InferenceResult, Namespace, TraitRef},
@@ -243,12 +242,8 @@ impl Module {
     }
 
     pub fn impl_blocks(self, db: &impl DefDatabase) -> Vec<ImplBlock> {
-        let module_impl_blocks = db.impls_in_module(self);
-        module_impl_blocks
-            .impls
-            .iter()
-            .map(|(impl_id, _)| ImplBlock::from_id(self, impl_id))
-            .collect()
+        let def_map = db.crate_def_map(self.id.krate);
+        def_map[self.id.module_id].impls.iter().copied().map(ImplBlock::from).collect()
     }
 
     fn with_module_id(self, module_id: CrateModuleId) -> Module {
@@ -693,8 +688,7 @@ impl Function {
 
     /// The containing impl block, if this is a method.
     pub fn impl_block(self, db: &impl DefDatabase) -> Option<ImplBlock> {
-        let module_impls = db.impls_in_module(self.module(db));
-        ImplBlock::containing(module_impls, self.into())
+        ImplBlock::containing(db, self.into())
     }
 
     /// The containing trait, if this is a trait method definition.
@@ -759,8 +753,7 @@ impl Const {
 
     /// The containing impl block, if this is a method.
     pub fn impl_block(self, db: &impl DefDatabase) -> Option<ImplBlock> {
-        let module_impls = db.impls_in_module(self.module(db));
-        ImplBlock::containing(module_impls, self.into())
+        ImplBlock::containing(db, self.into())
     }
 
     pub fn parent_trait(self, db: &impl DefDatabase) -> Option<Trait> {
@@ -973,8 +966,7 @@ impl TypeAlias {
 
     /// The containing impl block, if this is a method.
     pub fn impl_block(self, db: &impl DefDatabase) -> Option<ImplBlock> {
-        let module_impls = db.impls_in_module(self.module(db));
-        ImplBlock::containing(module_impls, self.into())
+        ImplBlock::containing(db, self.into())
     }
 
     /// The containing trait, if this is a trait method definition.
@@ -1137,3 +1129,8 @@ pub struct GenericParam {
     pub(crate) parent: GenericDef,
     pub(crate) idx: u32,
 }
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct ImplBlock {
+    pub(crate) id: ImplId,
+}
diff --git a/crates/ra_hir/src/db.rs b/crates/ra_hir/src/db.rs
index c60029c01..276b0774f 100644
--- a/crates/ra_hir/src/db.rs
+++ b/crates/ra_hir/src/db.rs
@@ -10,7 +10,6 @@ use crate::{
     debug::HirDebugDatabase,
     generics::{GenericDef, GenericParams},
     ids,
-    impl_block::{ImplBlock, ImplSourceMap, ModuleImplBlocks},
     lang_item::{LangItemTarget, LangItems},
     traits::TraitData,
     ty::{
@@ -18,14 +17,14 @@ use crate::{
         InferenceResult, Namespace, Substs, Ty, TypableDef, TypeCtor,
     },
     type_alias::TypeAliasData,
-    Const, ConstData, Crate, DefWithBody, FnData, Function, Module, Static, StructField, Trait,
-    TypeAlias,
+    Const, ConstData, Crate, DefWithBody, FnData, Function, ImplBlock, Module, Static, StructField,
+    Trait, TypeAlias,
 };
 
 pub use hir_def::db::{
     BodyQuery, BodyWithSourceMapQuery, CrateDefMapQuery, DefDatabase2, DefDatabase2Storage,
-    EnumDataQuery, ExprScopesQuery, InternDatabase, InternDatabaseStorage, RawItemsQuery,
-    RawItemsWithSourceMapQuery, StructDataQuery,
+    EnumDataQuery, ExprScopesQuery, ImplDataQuery, InternDatabase, InternDatabaseStorage,
+    RawItemsQuery, RawItemsWithSourceMapQuery, StructDataQuery,
 };
 pub use hir_expand::db::{
     AstDatabase, AstDatabaseStorage, AstIdMapQuery, MacroArgQuery, MacroDefQuery, MacroExpandQuery,
@@ -42,15 +41,6 @@ pub trait DefDatabase: HirDebugDatabase + DefDatabase2 {
     #[salsa::invoke(crate::traits::TraitItemsIndex::trait_items_index)]
     fn trait_items_index(&self, module: Module) -> crate::traits::TraitItemsIndex;
 
-    #[salsa::invoke(ModuleImplBlocks::impls_in_module_with_source_map_query)]
-    fn impls_in_module_with_source_map(
-        &self,
-        module: Module,
-    ) -> (Arc<ModuleImplBlocks>, Arc<ImplSourceMap>);
-
-    #[salsa::invoke(ModuleImplBlocks::impls_in_module_query)]
-    fn impls_in_module(&self, module: Module) -> Arc<ModuleImplBlocks>;
-
     #[salsa::invoke(crate::generics::GenericParams::generic_params_query)]
     fn generic_params(&self, def: GenericDef) -> Arc<GenericParams>;
 
@@ -128,7 +118,7 @@ pub trait HirDatabase: DefDatabase + AstDatabase {
     #[salsa::interned]
     fn intern_type_ctor(&self, type_ctor: TypeCtor) -> ids::TypeCtorId;
     #[salsa::interned]
-    fn intern_impl(&self, impl_: Impl) -> ids::GlobalImplId;
+    fn intern_chalk_impl(&self, impl_: Impl) -> ids::GlobalImplId;
 
     #[salsa::invoke(crate::ty::traits::chalk::associated_ty_data_query)]
     fn associated_ty_data(&self, id: chalk_ir::TypeId) -> Arc<chalk_rust_ir::AssociatedTyDatum>;
diff --git a/crates/ra_hir/src/from_id.rs b/crates/ra_hir/src/from_id.rs
index 9633ef586..f2203e995 100644
--- a/crates/ra_hir/src/from_id.rs
+++ b/crates/ra_hir/src/from_id.rs
@@ -3,9 +3,9 @@
 //! It's unclear if we need this long-term, but it's definitelly useful while we
 //! are splitting the hir.
 
-use hir_def::{AdtId, DefWithBodyId, EnumVariantId, ModuleDefId};
+use hir_def::{AdtId, AssocItemId, DefWithBodyId, EnumVariantId, ModuleDefId};
 
-use crate::{Adt, DefWithBody, EnumVariant, ModuleDef};
+use crate::{Adt, AssocItem, DefWithBody, EnumVariant, ModuleDef};
 
 macro_rules! from_id {
     ($(($id:path, $ty:path)),*) => {$(
@@ -27,6 +27,7 @@ from_id![
     (hir_def::StaticId, crate::Static),
     (hir_def::ConstId, crate::Const),
     (hir_def::FunctionId, crate::Function),
+    (hir_def::ImplId, crate::ImplBlock),
     (hir_expand::MacroDefId, crate::MacroDef)
 ];
 
@@ -71,3 +72,13 @@ impl From<DefWithBody> for DefWithBodyId {
         }
     }
 }
+
+impl From<AssocItemId> for AssocItem {
+    fn from(def: AssocItemId) -> Self {
+        match def {
+            AssocItemId::FunctionId(it) => AssocItem::Function(it.into()),
+            AssocItemId::TypeAliasId(it) => AssocItem::TypeAlias(it.into()),
+            AssocItemId::ConstId(it) => AssocItem::Const(it.into()),
+        }
+    }
+}
diff --git a/crates/ra_hir/src/from_source.rs b/crates/ra_hir/src/from_source.rs
index 7e5523c54..ec56dfa6a 100644
--- a/crates/ra_hir/src/from_source.rs
+++ b/crates/ra_hir/src/from_source.rs
@@ -82,14 +82,8 @@ impl FromSource for TypeAlias {
 impl FromSource for ImplBlock {
     type Ast = ast::ImplBlock;
     fn from_source(db: &(impl DefDatabase + AstDatabase), src: Source<Self::Ast>) -> Option<Self> {
-        let module_src = crate::ModuleSource::from_child_node(
-            db,
-            src.file_id.original_file(db),
-            &src.ast.syntax(),
-        );
-        let module = Module::from_definition(db, Source { file_id: src.file_id, ast: module_src })?;
-        let impls = module.impl_blocks(db);
-        impls.into_iter().find(|b| b.source(db) == src)
+        let id = from_source(db, src)?;
+        Some(ImplBlock { id })
     }
 }
 
diff --git a/crates/ra_hir/src/impl_block.rs b/crates/ra_hir/src/impl_block.rs
index b1a014074..0c2bb8fee 100644
--- a/crates/ra_hir/src/impl_block.rs
+++ b/crates/ra_hir/src/impl_block.rs
@@ -1,88 +1,38 @@
 //! FIXME: write short doc here
 
-use rustc_hash::FxHashMap;
-use std::sync::Arc;
-
-use hir_def::{attr::Attr, type_ref::TypeRef};
-use hir_expand::hygiene::Hygiene;
-use ra_arena::{impl_arena_id, map::ArenaMap, Arena, RawId};
-use ra_cfg::CfgOptions;
-use ra_syntax::{
-    ast::{self, AstNode},
-    AstPtr,
-};
+use hir_def::{type_ref::TypeRef, AstItemDef};
+use ra_syntax::ast::{self};
 
 use crate::{
-    code_model::{Module, ModuleSource},
     db::{AstDatabase, DefDatabase, HirDatabase},
     generics::HasGenericParams,
-    ids::LocationCtx,
-    ids::MacroCallLoc,
     resolve::Resolver,
     ty::Ty,
-    AssocItem, AstId, Const, Function, HasSource, HirFileId, MacroFileKind, Path, Source, TraitRef,
-    TypeAlias,
+    AssocItem, Crate, HasSource, ImplBlock, Module, Source, TraitRef,
 };
 
-#[derive(Debug, Default, PartialEq, Eq)]
-pub struct ImplSourceMap {
-    map: ArenaMap<ImplId, Source<AstPtr<ast::ImplBlock>>>,
-}
-
-impl ImplSourceMap {
-    fn insert(&mut self, impl_id: ImplId, file_id: HirFileId, impl_block: &ast::ImplBlock) {
-        let source = Source { file_id, ast: AstPtr::new(impl_block) };
-        self.map.insert(impl_id, source)
-    }
-
-    pub fn get(&self, db: &impl AstDatabase, impl_id: ImplId) -> Source<ast::ImplBlock> {
-        let src = self.map[impl_id];
-        let root = src.file_syntax(db);
-        src.map(|ptr| ptr.to_node(&root))
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct ImplBlock {
-    module: Module,
-    impl_id: ImplId,
-}
-
 impl HasSource for ImplBlock {
     type Ast = ast::ImplBlock;
     fn source(self, db: &(impl DefDatabase + AstDatabase)) -> Source<ast::ImplBlock> {
-        let source_map = db.impls_in_module_with_source_map(self.module).1;
-        source_map.get(db, self.impl_id)
+        self.id.source(db)
     }
 }
 
 impl ImplBlock {
-    pub(crate) fn containing(
-        module_impl_blocks: Arc<ModuleImplBlocks>,
-        item: AssocItem,
-    ) -> Option<ImplBlock> {
-        let impl_id = *module_impl_blocks.impls_by_def.get(&item)?;
-        Some(ImplBlock { module: module_impl_blocks.module, impl_id })
-    }
-
-    pub(crate) fn from_id(module: Module, impl_id: ImplId) -> ImplBlock {
-        ImplBlock { module, impl_id }
-    }
-
-    pub fn id(&self) -> ImplId {
-        self.impl_id
-    }
-
-    pub fn module(&self) -> Module {
-        self.module
+    pub(crate) fn containing(db: &impl DefDatabase, item: AssocItem) -> Option<ImplBlock> {
+        let module = item.module(db);
+        let crate_def_map = db.crate_def_map(module.id.krate);
+        crate_def_map[module.id.module_id].impls.iter().copied().map(ImplBlock::from).find(|it| {
+            db.impl_data(it.id).items().iter().copied().map(AssocItem::from).any(|it| it == item)
+        })
     }
 
     pub fn target_trait(&self, db: &impl DefDatabase) -> Option<TypeRef> {
-        db.impls_in_module(self.module).impls[self.impl_id].target_trait().cloned()
+        db.impl_data(self.id).target_trait().cloned()
     }
 
     pub fn target_type(&self, db: &impl DefDatabase) -> TypeRef {
-        db.impls_in_module(self.module).impls[self.impl_id].target_type().clone()
+        db.impl_data(self.id).target_type().clone()
     }
 
     pub fn target_ty(&self, db: &impl HirDatabase) -> Ty {
@@ -95,15 +45,23 @@ impl ImplBlock {
     }
 
     pub fn items(&self, db: &impl DefDatabase) -> Vec<AssocItem> {
-        db.impls_in_module(self.module).impls[self.impl_id].items().to_vec()
+        db.impl_data(self.id).items().iter().map(|it| (*it).into()).collect()
     }
 
     pub fn is_negative(&self, db: &impl DefDatabase) -> bool {
-        db.impls_in_module(self.module).impls[self.impl_id].negative
+        db.impl_data(self.id).is_negative()
+    }
+
+    pub fn module(&self, db: &impl DefDatabase) -> Module {
+        self.id.module(db).into()
+    }
+
+    pub fn krate(&self, db: &impl DefDatabase) -> Crate {
+        Crate { crate_id: self.module(db).id.krate }
     }
 
     pub(crate) fn resolver(&self, db: &impl DefDatabase) -> Resolver {
-        let r = self.module().resolver(db);
+        let r = self.module(db).resolver(db);
         // add generic params, if present
         let p = self.generic_params(db);
         let r = if !p.params.is_empty() { r.push_generic_params_scope(p) } else { r };
@@ -111,175 +69,3 @@ impl ImplBlock {
         r
     }
 }
-
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub struct ImplData {
-    target_trait: Option<TypeRef>,
-    target_type: TypeRef,
-    items: Vec<AssocItem>,
-    negative: bool,
-}
-
-impl ImplData {
-    pub(crate) fn from_ast(
-        db: &(impl DefDatabase + AstDatabase),
-        file_id: HirFileId,
-        module: Module,
-        node: &ast::ImplBlock,
-    ) -> Self {
-        let target_trait = node.target_trait().map(TypeRef::from_ast);
-        let target_type = TypeRef::from_ast_opt(node.target_type());
-        let ctx = LocationCtx::new(db, module.id, file_id);
-        let negative = node.is_negative();
-        let items = if let Some(item_list) = node.item_list() {
-            item_list
-                .impl_items()
-                .map(|item_node| match item_node {
-                    ast::ImplItem::FnDef(it) => Function { id: ctx.to_def(&it) }.into(),
-                    ast::ImplItem::ConstDef(it) => Const { id: ctx.to_def(&it) }.into(),
-                    ast::ImplItem::TypeAliasDef(it) => TypeAlias { id: ctx.to_def(&it) }.into(),
-                })
-                .collect()
-        } else {
-            Vec::new()
-        };
-        ImplData { target_trait, target_type, items, negative }
-    }
-
-    pub fn target_trait(&self) -> Option<&TypeRef> {
-        self.target_trait.as_ref()
-    }
-
-    pub fn target_type(&self) -> &TypeRef {
-        &self.target_type
-    }
-
-    pub fn items(&self) -> &[AssocItem] {
-        &self.items
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
-pub struct ImplId(pub RawId);
-impl_arena_id!(ImplId);
-
-/// The collection of impl blocks is a two-step process: first we collect the
-/// blocks per-module; then we build an index of all impl blocks in the crate.
-/// This way, we avoid having to do this process for the whole crate whenever
-/// a file is changed; as long as the impl blocks in the file don't change,
-/// we don't need to do the second step again.
-#[derive(Debug, PartialEq, Eq)]
-pub struct ModuleImplBlocks {
-    pub(crate) module: Module,
-    pub(crate) impls: Arena<ImplId, ImplData>,
-    impls_by_def: FxHashMap<AssocItem, ImplId>,
-}
-
-impl ModuleImplBlocks {
-    pub(crate) fn impls_in_module_with_source_map_query(
-        db: &(impl DefDatabase + AstDatabase),
-        module: Module,
-    ) -> (Arc<ModuleImplBlocks>, Arc<ImplSourceMap>) {
-        let mut source_map = ImplSourceMap::default();
-        let crate_graph = db.crate_graph();
-        let cfg_options = crate_graph.cfg_options(module.id.krate);
-
-        let result = ModuleImplBlocks::collect(db, cfg_options, module, &mut source_map);
-        (Arc::new(result), Arc::new(source_map))
-    }
-
-    pub(crate) fn impls_in_module_query(
-        db: &impl DefDatabase,
-        module: Module,
-    ) -> Arc<ModuleImplBlocks> {
-        db.impls_in_module_with_source_map(module).0
-    }
-
-    fn collect(
-        db: &(impl DefDatabase + AstDatabase),
-        cfg_options: &CfgOptions,
-        module: Module,
-        source_map: &mut ImplSourceMap,
-    ) -> Self {
-        let mut m = ModuleImplBlocks {
-            module,
-            impls: Arena::default(),
-            impls_by_def: FxHashMap::default(),
-        };
-
-        let src = m.module.definition_source(db);
-        match &src.ast {
-            ModuleSource::SourceFile(node) => {
-                m.collect_from_item_owner(db, cfg_options, source_map, node, src.file_id)
-            }
-            ModuleSource::Module(node) => {
-                let item_list = node.item_list().expect("inline module should have item list");
-                m.collect_from_item_owner(db, cfg_options, source_map, &item_list, src.file_id)
-            }
-        };
-        m
-    }
-
-    fn collect_from_item_owner(
-        &mut self,
-        db: &(impl DefDatabase + AstDatabase),
-        cfg_options: &CfgOptions,
-        source_map: &mut ImplSourceMap,
-        owner: &dyn ast::ModuleItemOwner,
-        file_id: HirFileId,
-    ) {
-        let hygiene = Hygiene::new(db, file_id);
-        for item in owner.items_with_macros() {
-            match item {
-                ast::ItemOrMacro::Item(ast::ModuleItem::ImplBlock(impl_block_ast)) => {
-                    let attrs = Attr::from_attrs_owner(&impl_block_ast, &hygiene);
-                    if attrs.map_or(false, |attrs| {
-                        attrs.iter().any(|attr| attr.is_cfg_enabled(cfg_options) == Some(false))
-                    }) {
-                        continue;
-                    }
-
-                    let impl_block = ImplData::from_ast(db, file_id, self.module, &impl_block_ast);
-                    let id = self.impls.alloc(impl_block);
-                    for &impl_item in &self.impls[id].items {
-                        self.impls_by_def.insert(impl_item, id);
-                    }
-
-                    source_map.insert(id, file_id, &impl_block_ast);
-                }
-                ast::ItemOrMacro::Item(_) => (),
-                ast::ItemOrMacro::Macro(macro_call) => {
-                    let attrs = Attr::from_attrs_owner(&macro_call, &hygiene);
-                    if attrs.map_or(false, |attrs| {
-                        attrs.iter().any(|attr| attr.is_cfg_enabled(cfg_options) == Some(false))
-                    }) {
-                        continue;
-                    }
-
-                    //FIXME: we should really cut down on the boilerplate required to process a macro
-                    let ast_id = AstId::new(file_id, db.ast_id_map(file_id).ast_id(&macro_call));
-                    if let Some(path) =
-                        macro_call.path().and_then(|path| Path::from_src(path, &hygiene))
-                    {
-                        if let Some(def) = self.module.resolver(db).resolve_path_as_macro(db, &path)
-                        {
-                            let call_id = db.intern_macro(MacroCallLoc { def: def.id, ast_id });
-                            let file_id = call_id.as_file(MacroFileKind::Items);
-                            if let Some(item_list) =
-                                db.parse_or_expand(file_id).and_then(ast::MacroItems::cast)
-                            {
-                                self.collect_from_item_owner(
-                                    db,
-                                    cfg_options,
-                                    source_map,
-                                    &item_list,
-                                    file_id,
-                                )
-                            }
-                        }
-                    }
-                }
-            }
-        }
-    }
-}
diff --git a/crates/ra_hir/src/lang_item.rs b/crates/ra_hir/src/lang_item.rs
index e1780ed38..fa2ef8a17 100644
--- a/crates/ra_hir/src/lang_item.rs
+++ b/crates/ra_hir/src/lang_item.rs
@@ -25,7 +25,7 @@ impl LangItemTarget {
         Some(match self {
             LangItemTarget::Enum(e) => e.module(db).krate(),
             LangItemTarget::Function(f) => f.module(db).krate(),
-            LangItemTarget::ImplBlock(i) => i.module().krate(),
+            LangItemTarget::ImplBlock(i) => i.krate(db),
             LangItemTarget::Static(s) => s.module(db).krate(),
             LangItemTarget::Struct(s) => s.module(db).krate(),
             LangItemTarget::Trait(t) => t.module(db).krate(),
diff --git a/crates/ra_hir/src/lib.rs b/crates/ra_hir/src/lib.rs
index 5ba847d35..da33c9591 100644
--- a/crates/ra_hir/src/lib.rs
+++ b/crates/ra_hir/src/lib.rs
@@ -54,12 +54,11 @@ mod test_db;
 #[cfg(test)]
 mod marks;
 
-use hir_expand::AstId;
-
-use crate::{ids::MacroFileKind, resolve::Resolver};
+use crate::resolve::Resolver;
 
 pub use crate::{
     adt::VariantDef,
+    code_model::ImplBlock,
     code_model::{
         attrs::{AttrDef, Attrs},
         docs::{DocDef, Docs, Documentation},
@@ -72,7 +71,6 @@ pub use crate::{
     from_source::FromSource,
     generics::GenericDef,
     ids::{HirFileId, MacroCallId, MacroCallLoc, MacroDefId, MacroFile},
-    impl_block::ImplBlock,
     resolve::ScopeDef,
     source_binder::{PathResolution, ScopeEntryWithSyntax, SourceAnalyzer},
     ty::{
diff --git a/crates/ra_hir/src/resolve.rs b/crates/ra_hir/src/resolve.rs
index 2fb913108..79b92180a 100644
--- a/crates/ra_hir/src/resolve.rs
+++ b/crates/ra_hir/src/resolve.rs
@@ -15,9 +15,8 @@ use crate::{
     db::{DefDatabase, HirDatabase},
     expr::{ExprScopes, PatId, ScopeId},
     generics::GenericParams,
-    impl_block::ImplBlock,
-    Adt, Const, DefWithBody, Enum, EnumVariant, Function, Local, MacroDef, ModuleDef, PerNs,
-    Static, Struct, Trait, TypeAlias,
+    Adt, Const, DefWithBody, Enum, EnumVariant, Function, ImplBlock, Local, MacroDef, ModuleDef,
+    PerNs, Static, Struct, Trait, TypeAlias,
 };
 
 #[derive(Debug, Clone, Default)]
diff --git a/crates/ra_hir/src/ty/method_resolution.rs b/crates/ra_hir/src/ty/method_resolution.rs
index eb5ca6769..9aad2d3fe 100644
--- a/crates/ra_hir/src/ty/method_resolution.rs
+++ b/crates/ra_hir/src/ty/method_resolution.rs
@@ -5,16 +5,14 @@
 use std::sync::Arc;
 
 use arrayvec::ArrayVec;
-use hir_def::CrateModuleId;
 use rustc_hash::FxHashMap;
 
 use crate::{
     db::HirDatabase,
-    impl_block::{ImplBlock, ImplId},
     resolve::Resolver,
     ty::primitive::{FloatBitness, Uncertain},
     ty::{Ty, TypeCtor},
-    AssocItem, Crate, Function, Module, Mutability, Name, Trait,
+    AssocItem, Crate, Function, ImplBlock, Module, Mutability, Name, Trait,
 };
 
 use super::{autoderef, lower, Canonical, InEnvironment, TraitEnvironment, TraitRef};
@@ -39,65 +37,46 @@ impl TyFingerprint {
 
 #[derive(Debug, PartialEq, Eq)]
 pub struct CrateImplBlocks {
-    /// To make sense of the CrateModuleIds, we need the source root.
-    krate: Crate,
-    impls: FxHashMap<TyFingerprint, Vec<(CrateModuleId, ImplId)>>,
-    impls_by_trait: FxHashMap<Trait, Vec<(CrateModuleId, ImplId)>>,
+    impls: FxHashMap<TyFingerprint, Vec<ImplBlock>>,
+    impls_by_trait: FxHashMap<Trait, Vec<ImplBlock>>,
 }
 
 impl CrateImplBlocks {
-    pub fn lookup_impl_blocks<'a>(&'a self, ty: &Ty) -> impl Iterator<Item = ImplBlock> + 'a {
+    pub(crate) fn impls_in_crate_query(
+        db: &impl HirDatabase,
+        krate: Crate,
+    ) -> Arc<CrateImplBlocks> {
+        let mut crate_impl_blocks =
+            CrateImplBlocks { impls: FxHashMap::default(), impls_by_trait: FxHashMap::default() };
+        if let Some(module) = krate.root_module(db) {
+            crate_impl_blocks.collect_recursive(db, module);
+        }
+        Arc::new(crate_impl_blocks)
+    }
+    pub fn lookup_impl_blocks(&self, ty: &Ty) -> impl Iterator<Item = ImplBlock> + '_ {
         let fingerprint = TyFingerprint::for_impl(ty);
-        fingerprint.and_then(|f| self.impls.get(&f)).into_iter().flat_map(|i| i.iter()).map(
-            move |(module_id, impl_id)| {
-                let module = Module::new(self.krate, *module_id);
-                ImplBlock::from_id(module, *impl_id)
-            },
-        )
+        fingerprint.and_then(|f| self.impls.get(&f)).into_iter().flatten().copied()
     }
 
-    pub fn lookup_impl_blocks_for_trait<'a>(
-        &'a self,
-        tr: Trait,
-    ) -> impl Iterator<Item = ImplBlock> + 'a {
-        self.impls_by_trait.get(&tr).into_iter().flat_map(|i| i.iter()).map(
-            move |(module_id, impl_id)| {
-                let module = Module::new(self.krate, *module_id);
-                ImplBlock::from_id(module, *impl_id)
-            },
-        )
+    pub fn lookup_impl_blocks_for_trait(&self, tr: Trait) -> impl Iterator<Item = ImplBlock> + '_ {
+        self.impls_by_trait.get(&tr).into_iter().flatten().copied()
     }
 
     pub fn all_impls<'a>(&'a self) -> impl Iterator<Item = ImplBlock> + 'a {
-        self.impls.values().chain(self.impls_by_trait.values()).flat_map(|i| i.iter()).map(
-            move |(module_id, impl_id)| {
-                let module = Module::new(self.krate, *module_id);
-                ImplBlock::from_id(module, *impl_id)
-            },
-        )
+        self.impls.values().chain(self.impls_by_trait.values()).flatten().copied()
     }
 
     fn collect_recursive(&mut self, db: &impl HirDatabase, module: Module) {
-        let module_impl_blocks = db.impls_in_module(module);
-
-        for (impl_id, _) in module_impl_blocks.impls.iter() {
-            let impl_block = ImplBlock::from_id(module_impl_blocks.module, impl_id);
-
+        for impl_block in module.impl_blocks(db) {
             let target_ty = impl_block.target_ty(db);
 
             if impl_block.target_trait(db).is_some() {
                 if let Some(tr) = impl_block.target_trait_ref(db) {
-                    self.impls_by_trait
-                        .entry(tr.trait_)
-                        .or_insert_with(Vec::new)
-                        .push((module.id.module_id, impl_id));
+                    self.impls_by_trait.entry(tr.trait_).or_default().push(impl_block);
                 }
             } else {
                 if let Some(target_ty_fp) = TyFingerprint::for_impl(&target_ty) {
-                    self.impls
-                        .entry(target_ty_fp)
-                        .or_insert_with(Vec::new)
-                        .push((module.id.module_id, impl_id));
+                    self.impls.entry(target_ty_fp).or_default().push(impl_block);
                 }
             }
         }
@@ -106,21 +85,6 @@ impl CrateImplBlocks {
             self.collect_recursive(db, child);
         }
     }
-
-    pub(crate) fn impls_in_crate_query(
-        db: &impl HirDatabase,
-        krate: Crate,
-    ) -> Arc<CrateImplBlocks> {
-        let mut crate_impl_blocks = CrateImplBlocks {
-            krate,
-            impls: FxHashMap::default(),
-            impls_by_trait: FxHashMap::default(),
-        };
-        if let Some(module) = krate.root_module(db) {
-            crate_impl_blocks.collect_recursive(db, module);
-        }
-        Arc::new(crate_impl_blocks)
-    }
 }
 
 fn def_crates(db: &impl HirDatabase, cur_crate: Crate, ty: &Ty) -> Option<ArrayVec<[Crate; 2]>> {
diff --git a/crates/ra_hir/src/ty/traits/chalk.rs b/crates/ra_hir/src/ty/traits/chalk.rs
index 75351c17d..68304b950 100644
--- a/crates/ra_hir/src/ty/traits/chalk.rs
+++ b/crates/ra_hir/src/ty/traits/chalk.rs
@@ -191,11 +191,11 @@ impl ToChalk for Impl {
     type Chalk = chalk_ir::ImplId;
 
     fn to_chalk(self, db: &impl HirDatabase) -> chalk_ir::ImplId {
-        db.intern_impl(self).into()
+        db.intern_chalk_impl(self).into()
     }
 
     fn from_chalk(db: &impl HirDatabase, impl_id: chalk_ir::ImplId) -> Impl {
-        db.lookup_intern_impl(impl_id.into())
+        db.lookup_intern_chalk_impl(impl_id.into())
     }
 }
 
@@ -630,7 +630,7 @@ fn impl_block_datum(
         .target_trait_ref(db)
         .expect("FIXME handle unresolved impl block trait ref")
         .subst(&bound_vars);
-    let impl_type = if impl_block.module().krate() == krate {
+    let impl_type = if impl_block.krate(db) == krate {
         chalk_rust_ir::ImplType::Local
     } else {
         chalk_rust_ir::ImplType::External
diff --git a/crates/ra_hir_def/src/db.rs b/crates/ra_hir_def/src/db.rs
index 40b5920d9..348aca07f 100644
--- a/crates/ra_hir_def/src/db.rs
+++ b/crates/ra_hir_def/src/db.rs
@@ -8,30 +8,32 @@ use ra_syntax::ast;
 use crate::{
     adt::{EnumData, StructData},
     body::{scope::ExprScopes, Body, BodySourceMap},
+    imp::ImplData,
     nameres::{
         raw::{ImportSourceMap, RawItems},
         CrateDefMap,
     },
-    DefWithBodyId, EnumId, StructOrUnionId,
+    DefWithBodyId, EnumId, ImplId, ItemLoc, StructOrUnionId,
 };
 
 #[salsa::query_group(InternDatabaseStorage)]
 pub trait InternDatabase: SourceDatabase {
     #[salsa::interned]
-    fn intern_function(&self, loc: crate::ItemLoc<ast::FnDef>) -> crate::FunctionId;
+    fn intern_function(&self, loc: ItemLoc<ast::FnDef>) -> crate::FunctionId;
     #[salsa::interned]
-    fn intern_struct_or_union(&self, loc: crate::ItemLoc<ast::StructDef>)
-        -> crate::StructOrUnionId;
+    fn intern_struct_or_union(&self, loc: ItemLoc<ast::StructDef>) -> crate::StructOrUnionId;
     #[salsa::interned]
-    fn intern_enum(&self, loc: crate::ItemLoc<ast::EnumDef>) -> crate::EnumId;
+    fn intern_enum(&self, loc: ItemLoc<ast::EnumDef>) -> crate::EnumId;
     #[salsa::interned]
-    fn intern_const(&self, loc: crate::ItemLoc<ast::ConstDef>) -> crate::ConstId;
+    fn intern_const(&self, loc: ItemLoc<ast::ConstDef>) -> crate::ConstId;
     #[salsa::interned]
-    fn intern_static(&self, loc: crate::ItemLoc<ast::StaticDef>) -> crate::StaticId;
+    fn intern_static(&self, loc: ItemLoc<ast::StaticDef>) -> crate::StaticId;
     #[salsa::interned]
-    fn intern_trait(&self, loc: crate::ItemLoc<ast::TraitDef>) -> crate::TraitId;
+    fn intern_trait(&self, loc: ItemLoc<ast::TraitDef>) -> crate::TraitId;
     #[salsa::interned]
-    fn intern_type_alias(&self, loc: crate::ItemLoc<ast::TypeAliasDef>) -> crate::TypeAliasId;
+    fn intern_type_alias(&self, loc: ItemLoc<ast::TypeAliasDef>) -> crate::TypeAliasId;
+    #[salsa::interned]
+    fn intern_impl(&self, loc: ItemLoc<ast::ImplBlock>) -> crate::ImplId;
 }
 
 #[salsa::query_group(DefDatabase2Storage)]
@@ -54,6 +56,9 @@ pub trait DefDatabase2: InternDatabase + AstDatabase {
     #[salsa::invoke(EnumData::enum_data_query)]
     fn enum_data(&self, e: EnumId) -> Arc<EnumData>;
 
+    #[salsa::invoke(ImplData::impl_data_query)]
+    fn impl_data(&self, e: ImplId) -> Arc<ImplData>;
+
     #[salsa::invoke(Body::body_with_source_map_query)]
     fn body_with_source_map(&self, def: DefWithBodyId) -> (Arc<Body>, Arc<BodySourceMap>);
 
diff --git a/crates/ra_hir_def/src/imp.rs b/crates/ra_hir_def/src/imp.rs
new file mode 100644
index 000000000..717991c40
--- /dev/null
+++ b/crates/ra_hir_def/src/imp.rs
@@ -0,0 +1,71 @@
+//! Defines hir-level representation of impls.
+//!
+//! The handling is similar, but is not quite the same as for other items,
+//! because `impl`s don't have names.
+
+use std::sync::Arc;
+
+use ra_syntax::ast;
+
+use crate::{
+    db::DefDatabase2, type_ref::TypeRef, AssocItemId, AstItemDef, ConstId, FunctionId, ImplId,
+    LocationCtx, TypeAliasId,
+};
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct ImplData {
+    target_trait: Option<TypeRef>,
+    target_type: TypeRef,
+    items: Vec<AssocItemId>,
+    negative: bool,
+}
+
+impl ImplData {
+    pub(crate) fn impl_data_query(db: &impl DefDatabase2, id: ImplId) -> Arc<ImplData> {
+        let src = id.source(db);
+        let items = db.ast_id_map(src.file_id);
+
+        let target_trait = src.ast.target_trait().map(TypeRef::from_ast);
+        let target_type = TypeRef::from_ast_opt(src.ast.target_type());
+        let negative = src.ast.is_negative();
+
+        let items = if let Some(item_list) = src.ast.item_list() {
+            let ctx = LocationCtx::new(db, id.module(db), src.file_id);
+            item_list
+                .impl_items()
+                .map(|item_node| match item_node {
+                    ast::ImplItem::FnDef(it) => {
+                        FunctionId::from_ast_id(ctx, items.ast_id(&it)).into()
+                    }
+                    ast::ImplItem::ConstDef(it) => {
+                        ConstId::from_ast_id(ctx, items.ast_id(&it)).into()
+                    }
+                    ast::ImplItem::TypeAliasDef(it) => {
+                        TypeAliasId::from_ast_id(ctx, items.ast_id(&it)).into()
+                    }
+                })
+                .collect()
+        } else {
+            Vec::new()
+        };
+
+        let res = ImplData { target_trait, target_type, items, negative };
+        Arc::new(res)
+    }
+
+    pub fn target_trait(&self) -> Option<&TypeRef> {
+        self.target_trait.as_ref()
+    }
+
+    pub fn target_type(&self) -> &TypeRef {
+        &self.target_type
+    }
+
+    pub fn items(&self) -> &[AssocItemId] {
+        &self.items
+    }
+
+    pub fn is_negative(&self) -> bool {
+        self.negative
+    }
+}
diff --git a/crates/ra_hir_def/src/lib.rs b/crates/ra_hir_def/src/lib.rs
index 3fab7965c..0a59c4ad7 100644
--- a/crates/ra_hir_def/src/lib.rs
+++ b/crates/ra_hir_def/src/lib.rs
@@ -13,6 +13,7 @@ pub mod path;
 pub mod type_ref;
 pub mod builtin_type;
 pub mod adt;
+pub mod imp;
 pub mod diagnostics;
 pub mod expr;
 pub mod body;
@@ -321,6 +322,18 @@ impl AstItemDef<ast::TypeAliasDef> for TypeAliasId {
     }
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct ImplId(salsa::InternId);
+impl_intern_key!(ImplId);
+impl AstItemDef<ast::ImplBlock> for ImplId {
+    fn intern(db: &impl InternDatabase, loc: ItemLoc<ast::ImplBlock>) -> Self {
+        db.intern_impl(loc)
+    }
+    fn lookup_intern(self, db: &impl InternDatabase) -> ItemLoc<ast::ImplBlock> {
+        db.lookup_intern_impl(self)
+    }
+}
+
 macro_rules! impl_froms {
     ($e:ident: $($v:ident $(($($sv:ident),*))?),*) => {
         $(
@@ -384,3 +397,15 @@ pub enum DefWithBodyId {
 }
 
 impl_froms!(DefWithBodyId: FunctionId, ConstId, StaticId);
+
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+pub enum AssocItemId {
+    FunctionId(FunctionId),
+    ConstId(ConstId),
+    TypeAliasId(TypeAliasId),
+}
+// FIXME: not every function, ... is actually an assoc item. maybe we should make
+// sure that you can only turn actual assoc items into AssocItemIds. This would
+// require not implementing From, and instead having some checked way of
+// casting them, and somehow making the constructors private, which would be annoying.
+impl_froms!(AssocItemId: FunctionId, ConstId, TypeAliasId);
diff --git a/crates/ra_hir_def/src/nameres.rs b/crates/ra_hir_def/src/nameres.rs
index dfcec6443..49e33ccc4 100644
--- a/crates/ra_hir_def/src/nameres.rs
+++ b/crates/ra_hir_def/src/nameres.rs
@@ -73,7 +73,7 @@ use crate::{
         diagnostics::DefDiagnostic, path_resolution::ResolveMode, per_ns::PerNs, raw::ImportId,
     },
     path::Path,
-    AstId, CrateModuleId, FunctionId, ModuleDefId, ModuleId, TraitId,
+    AstId, CrateModuleId, FunctionId, ImplId, ModuleDefId, ModuleId, TraitId,
 };
 
 /// Contains all top-level defs from a macro-expanded crate
@@ -122,6 +122,7 @@ pub struct ModuleData {
     ///
     /// Note that non-inline modules, by definition, live inside non-macro file.
     pub definition: Option<FileId>,
+    pub impls: Vec<ImplId>,
 }
 
 #[derive(Default, Debug, PartialEq, Eq, Clone)]
diff --git a/crates/ra_hir_def/src/nameres/collector.rs b/crates/ra_hir_def/src/nameres/collector.rs
index 5c899aff3..c9ccb9023 100644
--- a/crates/ra_hir_def/src/nameres/collector.rs
+++ b/crates/ra_hir_def/src/nameres/collector.rs
@@ -19,7 +19,7 @@ use crate::{
         per_ns::PerNs, raw, CrateDefMap, ModuleData, Resolution, ResolveMode,
     },
     path::{Path, PathKind},
-    AdtId, AstId, AstItemDef, ConstId, CrateModuleId, EnumId, EnumVariantId, FunctionId,
+    AdtId, AstId, AstItemDef, ConstId, CrateModuleId, EnumId, EnumVariantId, FunctionId, ImplId,
     LocationCtx, ModuleDefId, ModuleId, StaticId, StructId, StructOrUnionId, TraitId, TypeAliasId,
     UnionId,
 };
@@ -571,6 +571,15 @@ where
                         .push((self.module_id, import_id, self.raw_items[import_id].clone())),
                     raw::RawItemKind::Def(def) => self.define_def(&self.raw_items[def]),
                     raw::RawItemKind::Macro(mac) => self.collect_macro(&self.raw_items[mac]),
+                    raw::RawItemKind::Impl(imp) => {
+                        let module = ModuleId {
+                            krate: self.def_collector.def_map.krate,
+                            module_id: self.module_id,
+                        };
+                        let ctx = LocationCtx::new(self.def_collector.db, module, self.file_id);
+                        let imp_id = ImplId::from_ast_id(ctx, self.raw_items[imp].ast_id);
+                        self.def_collector.def_map.modules[self.module_id].impls.push(imp_id)
+                    }
                 }
             }
         }
diff --git a/crates/ra_hir_def/src/nameres/raw.rs b/crates/ra_hir_def/src/nameres/raw.rs
index f52002bc0..a0a2c7273 100644
--- a/crates/ra_hir_def/src/nameres/raw.rs
+++ b/crates/ra_hir_def/src/nameres/raw.rs
@@ -28,6 +28,7 @@ pub struct RawItems {
     imports: Arena<ImportId, ImportData>,
     defs: Arena<Def, DefData>,
     macros: Arena<Macro, MacroData>,
+    impls: Arena<Impl, ImplData>,
     /// items for top-level module
     items: Vec<RawItem>,
 }
@@ -121,6 +122,13 @@ impl Index<Macro> for RawItems {
     }
 }
 
+impl Index<Impl> for RawItems {
+    type Output = ImplData;
+    fn index(&self, idx: Impl) -> &ImplData {
+        &self.impls[idx]
+    }
+}
+
 // Avoid heap allocation on items without attributes.
 type Attrs = Option<Arc<[Attr]>>;
 
@@ -142,6 +150,7 @@ pub(super) enum RawItemKind {
     Import(ImportId),
     Def(Def),
     Macro(Macro),
+    Impl(Impl),
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
@@ -203,6 +212,15 @@ pub(super) struct MacroData {
     pub(super) builtin: bool,
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub(super) struct Impl(RawId);
+impl_arena_id!(Impl);
+
+#[derive(Debug, PartialEq, Eq)]
+pub(super) struct ImplData {
+    pub(super) ast_id: FileAstId<ast::ImplBlock>,
+}
+
 struct RawItemsCollector {
     raw_items: RawItems,
     source_ast_id_map: Arc<AstIdMap>,
@@ -236,8 +254,8 @@ impl RawItemsCollector {
                 self.add_extern_crate_item(current_module, extern_crate);
                 return;
             }
-            ast::ModuleItem::ImplBlock(_) => {
-                // impls don't participate in name resolution
+            ast::ModuleItem::ImplBlock(it) => {
+                self.add_impl(current_module, it);
                 return;
             }
             ast::ModuleItem::StructDef(it) => {
@@ -376,6 +394,13 @@ impl RawItemsCollector {
         self.push_item(current_module, attrs, RawItemKind::Macro(m));
     }
 
+    fn add_impl(&mut self, current_module: Option<Module>, imp: ast::ImplBlock) {
+        let attrs = self.parse_attrs(&imp);
+        let ast_id = self.source_ast_id_map.ast_id(&imp);
+        let imp = self.raw_items.impls.alloc(ImplData { ast_id });
+        self.push_item(current_module, attrs, RawItemKind::Impl(imp))
+    }
+
     fn push_import(
         &mut self,
         current_module: Option<Module>,
diff --git a/crates/ra_ide_api/src/change.rs b/crates/ra_ide_api/src/change.rs
index 010b45141..5c9dec13e 100644
--- a/crates/ra_ide_api/src/change.rs
+++ b/crates/ra_ide_api/src/change.rs
@@ -271,7 +271,6 @@ impl RootDatabase {
         self.query(hir::db::AstIdMapQuery).sweep(sweep);
 
         self.query(hir::db::RawItemsWithSourceMapQuery).sweep(sweep);
-        self.query(hir::db::ImplsInModuleWithSourceMapQuery).sweep(sweep);
         self.query(hir::db::BodyWithSourceMapQuery).sweep(sweep);
 
         self.query(hir::db::ExprScopesQuery).sweep(sweep);
@@ -314,8 +313,6 @@ impl RootDatabase {
             hir::db::RawItemsWithSourceMapQuery
             hir::db::RawItemsQuery
             hir::db::CrateDefMapQuery
-            hir::db::ImplsInModuleWithSourceMapQuery
-            hir::db::ImplsInModuleQuery
             hir::db::GenericParamsQuery
             hir::db::FnDataQuery
             hir::db::TypeAliasDataQuery
@@ -340,6 +337,7 @@ impl RootDatabase {
             hir::db::TraitDatumQuery
             hir::db::StructDatumQuery
             hir::db::ImplDatumQuery
+            hir::db::ImplDataQuery
             hir::db::TraitSolveQuery
         ];
         acc.sort_by_key(|it| std::cmp::Reverse(it.1));
diff --git a/crates/ra_ide_api/src/references/classify.rs b/crates/ra_ide_api/src/references/classify.rs
index 217f9951e..00690e449 100644
--- a/crates/ra_ide_api/src/references/classify.rs
+++ b/crates/ra_ide_api/src/references/classify.rs
@@ -114,8 +114,6 @@ pub(crate) fn classify_name_ref(
     file_id: FileId,
     name_ref: &ast::NameRef,
 ) -> Option<NameDefinition> {
-    use PathResolution::*;
-
     let _p = profile("classify_name_ref");
 
     let parent = name_ref.syntax().parent()?;
@@ -163,26 +161,26 @@ pub(crate) fn classify_name_ref(
     let path = name_ref.syntax().ancestors().find_map(ast::Path::cast)?;
     let resolved = analyzer.resolve_path(db, &path)?;
     match resolved {
-        Def(def) => Some(from_module_def(db, def, Some(container))),
-        AssocItem(item) => Some(from_assoc_item(db, item)),
-        Local(local) => {
+        PathResolution::Def(def) => Some(from_module_def(db, def, Some(container))),
+        PathResolution::AssocItem(item) => Some(from_assoc_item(db, item)),
+        PathResolution::Local(local) => {
             let container = local.module(db);
             let kind = NameKind::Local(local);
             Some(NameDefinition { kind, container, visibility: None })
         }
-        GenericParam(par) => {
+        PathResolution::GenericParam(par) => {
             // FIXME: get generic param def
             let kind = NameKind::GenericParam(par);
             Some(NameDefinition { kind, container, visibility })
         }
-        Macro(def) => {
+        PathResolution::Macro(def) => {
             let kind = NameKind::Macro(def);
             Some(NameDefinition { kind, container, visibility })
         }
-        SelfType(impl_block) => {
+        PathResolution::SelfType(impl_block) => {
             let ty = impl_block.target_ty(db);
             let kind = NameKind::SelfType(ty);
-            let container = impl_block.module();
+            let container = impl_block.module(db);
             Some(NameDefinition { kind, container, visibility })
         }
     }