groundwork: create the Resolver earlier in phase 2

src/librustc/hir/map/def_collector.rs

@@ -25,15 +25,15 @@ pub struct DefCollector<'ast> {
     // If we are walking HIR (c.f., AST), we need to keep a reference to the
     // crate.
     hir_crate: Option<&'ast hir::Crate>,
-    pub definitions: Definitions,
+    definitions: &'ast mut Definitions,
     parent_def: Option<DefIndex>,
 }
 
 impl<'ast> DefCollector<'ast> {
-    pub fn root() -> DefCollector<'ast> {
+    pub fn root(definitions: &'ast mut Definitions) -> DefCollector<'ast> {
         let mut collector = DefCollector {
             hir_crate: None,
-            definitions: Definitions::new(),
+            definitions: definitions,
             parent_def: None,
         };
         let root = collector.create_def_with_parent(None, CRATE_NODE_ID, DefPathData::CrateRoot);
@@ -48,7 +48,7 @@ impl<'ast> DefCollector<'ast> {
     pub fn extend(parent_node: NodeId,
                   parent_def_path: DefPath,
                   parent_def_id: DefId,
-                  definitions: Definitions)
+                  definitions: &'ast mut Definitions)
                   -> DefCollector<'ast> {
         let mut collector = DefCollector {
             hir_crate: None,

src/librustc/hir/map/definitions.rs

@@ -10,8 +10,9 @@
 
 use middle::cstore::LOCAL_CRATE;
 use hir::def_id::{DefId, DefIndex};
+use hir::map::def_collector::DefCollector;
 use rustc_data_structures::fnv::FnvHashMap;
-use syntax::ast;
+use syntax::{ast, visit};
 use syntax::parse::token::InternedString;
 use util::nodemap::NodeMap;
 
@@ -189,6 +190,11 @@ impl Definitions {
         }
     }
 
+    pub fn collect(&mut self, krate: &ast::Crate) {
+        let mut def_collector = DefCollector::root(self);
+        visit::walk_crate(&mut def_collector, krate);
+    }
+
     /// Get the number of definitions.
     pub fn len(&self) -> usize {
         self.data.len()

src/librustc/hir/map/mod.rs

@@ -24,7 +24,6 @@ use hir::def_id::{CRATE_DEF_INDEX, DefId, DefIndex};
 use syntax::abi::Abi;
 use syntax::ast::{self, Name, NodeId, DUMMY_NODE_ID, };
 use syntax::codemap::Spanned;
-use syntax::visit;
 use syntax_pos::Span;
 
 use hir::*;
@@ -780,12 +779,6 @@ impl<F: FoldOps> Folder for IdAndSpanUpdater<F> {
     }
 }
 
-pub fn collect_definitions<'ast>(krate: &'ast ast::Crate) -> Definitions {
-    let mut def_collector = DefCollector::root();
-    visit::walk_crate(&mut def_collector, krate);
-    def_collector.definitions
-}
-
 pub fn map_crate<'ast>(forest: &'ast mut Forest,
                        definitions: Definitions)
                        -> Map<'ast> {
@@ -842,13 +835,12 @@ pub fn map_decoded_item<'ast, F: FoldOps>(map: &Map<'ast>,
     let ii = map.forest.inlined_items.alloc(ii);
     let ii_parent_id = fld.new_id(DUMMY_NODE_ID);
 
-    let defs = mem::replace(&mut *map.definitions.borrow_mut(), Definitions::new());
+    let defs = &mut *map.definitions.borrow_mut();
     let mut def_collector = DefCollector::extend(ii_parent_id,
                                                  parent_def_path.clone(),
                                                  parent_def_id,
                                                  defs);
     def_collector.walk_item(ii, map.krate());
-    *map.definitions.borrow_mut() = def_collector.definitions;
 
     let mut collector = NodeCollector::extend(map.krate(),
                                               ii,

src/librustc_driver/driver.rs

@@ -726,13 +726,16 @@ pub fn phase_2_configure_and_expand<'a>(sess: &Session,
 
     krate = assign_node_ids(sess, krate);
 
-    // Collect defintions for def ids.
-    let defs =
-        time(sess.time_passes(), "collecting defs", || hir_map::collect_definitions(&krate));
+    let resolver_arenas = Resolver::arenas();
+    let mut resolver = Resolver::new(sess, make_glob_map, &resolver_arenas);
 
-    time(sess.time_passes(),
-         "external crate/lib resolution",
-         || read_local_crates(sess, &cstore, &defs, &krate, crate_name, &sess.dep_graph));
+    // Collect defintions for def ids.
+    time(sess.time_passes(), "collecting defs", || resolver.definitions.collect(&krate));
+
+    time(sess.time_passes(), "external crate/lib resolution", || {
+        let defs = &resolver.definitions;
+        read_local_crates(sess, &cstore, defs, &krate, crate_name, &sess.dep_graph)
+    });
 
     time(sess.time_passes(),
          "early lint checks",
@@ -742,9 +745,6 @@ pub fn phase_2_configure_and_expand<'a>(sess: &Session,
          "AST validation",
          || ast_validation::check_crate(sess, &krate));
 
-    let resolver_arenas = Resolver::arenas();
-    let mut resolver = Resolver::new(sess, defs, make_glob_map, &resolver_arenas);
-
     time(sess.time_passes(), "name resolution", || {
         resolver.resolve_crate(&krate);
     });

src/librustc_resolve/lib.rs

@@ -47,7 +47,7 @@ use rustc::hir::{self, PrimTy, TyBool, TyChar, TyFloat, TyInt, TyUint, TyStr};
 use rustc::session::Session;
 use rustc::lint;
 use rustc::hir::def::*;
-use rustc::hir::def_id::DefId;
+use rustc::hir::def_id::{CRATE_DEF_INDEX, DefId};
 use rustc::ty;
 use rustc::ty::subst::{ParamSpace, FnSpace, TypeSpace};
 use rustc::hir::{Freevar, FreevarMap, TraitCandidate, TraitMap, GlobMap};
@@ -1100,12 +1100,9 @@ impl Named for hir::PathSegment {
 }
 
 impl<'a> Resolver<'a> {
-    pub fn new(session: &'a Session,
-               definitions: Definitions,
-               make_glob_map: MakeGlobMap,
-               arenas: &'a ResolverArenas<'a>)
+    pub fn new(session: &'a Session, make_glob_map: MakeGlobMap, arenas: &'a ResolverArenas<'a>)
                -> Resolver<'a> {
-        let root_def_id = definitions.local_def_id(CRATE_NODE_ID);
+        let root_def_id = DefId::local(CRATE_DEF_INDEX);
         let graph_root =
             ModuleS::new(NoParentLink, Some(Def::Mod(root_def_id)), false, arenas);
         let graph_root = arenas.alloc_module(graph_root);
@@ -1115,7 +1112,7 @@ impl<'a> Resolver<'a> {
         Resolver {
             session: session,
 
-            definitions: definitions,
+            definitions: Definitions::new(),
 
             // The outermost module has def ID 0; this is not reflected in the
             // AST.