A visitor that builds a map from node to "Usage".

lib/compiler/implementation/dart_backend/backend.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 class BailoutException {
   final String reason;
 
   const BailoutException(this.reason);
 }
 
@@ skipping 52 matching lines @@
     final LIBS_TO_IGNORE = [
       compiler.jsHelperLibrary,
       compiler.interceptorsLibrary,
     ];
     bool shouldOutput(Element element) =>
       element.kind !== ElementKind.VOID &&
       LIBS_TO_IGNORE.indexOf(element.getLibrary()) == -1 &&
       !isDartCoreLib(compiler, element.getLibrary());
 
     try {
-      Emitter emitter = new Emitter(compiler);
+      Usager usager = new Usager(compiler);
+      resolvedElements.forEach((element, treeElements) {
+        if (!shouldOutput(element)
+            || element is SynthesizedConstructorElement

[Anton Muhin, 2012/08/07 12:32:11]

why this is not a part of shouldOutput?

and we have pretty much the same logic in Emitter.outputElement, shouldn't we
unify it?

[Roman, 2012/08/07 15:44:03]

We should, but I'm not sure what would be the nice way to do that. We don't have
this check in shouldOutput, because if we see AbstractFieldMember or
constructor, we still should call addMemberToClass(), otherwise class A that has
only constructor used, will not be emitted.

+            || element is AbstractFieldElement) return;
+        usager.process(element, treeElements);
+      });
+      ConflictingRenamer renamer =
+          new ConflictingRenamer(compiler, usager.usages);
+      Emitter emitter = new Emitter(compiler, renamer);
       resolvedElements.forEach((element, treeElements) {
         if (!shouldOutput(element)) return;
         if (element.isMember()) {
           var enclosingClass = element.enclosingElement;
           assert(enclosingClass.isClass());
           assert(enclosingClass.isTopLevel());
           addMemberToClass(element, enclosingClass);
           return;
         }
         if (!element.isTopLevel()) {
@@ skipping 24 matching lines @@
  */
 bool isDartCoreLib(Compiler compiler, LibraryElement libraryElement) {
   final libraries = compiler.libraries;
   for (final uri in libraries.getKeys()) {
     if (libraryElement === libraries[uri]) {
       if (uri.startsWith('dart:')) return true;
     }
   }
   return false;
 }