dart2js: Create program_builder directory and move corresponding files.

pkg/compiler/lib/src/js_emitter/registry.dart

-// Copyright (c) 2014, 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.
-
-part of dart2js.js_emitter.program_builder;
-
-/// Maps [LibraryElement]s to their [Element]s.
-///
-/// Fundamentally, this class nicely encapsulates a
-/// `Map<LibraryElement, List<Element>>`.
-///
-/// There exists exactly one instance per [OutputUnit].
-class LibrariesMap {
-  final Map<LibraryElement, List<Element>> _mapping =
-      <LibraryElement, List<Element>>{};
-
-  // It is very common to access the same library multiple times in a row, so
-  // we cache the last access.
-  LibraryElement _lastLibrary;
-  List<Element> _lastElements;
-
-  /// A unique name representing this instance.
-  final String name;
-  final OutputUnit outputUnit;
-
-  LibrariesMap.main(this.outputUnit) : name = "";
-
-  LibrariesMap.deferred(this.outputUnit, this.name) {
-    assert(name != "");
-  }
-
-  void add(LibraryElement library, Element element) {
-    if (_lastLibrary != library) {
-      _lastLibrary = library;
-      _lastElements = _mapping.putIfAbsent(library, () => <Element>[]);
-    }
-    _lastElements.add(element);
-  }
-
-  int get length => _mapping.length;
-
-  void forEach(void f(LibraryElement library, List<Element> elements)) {
-    _mapping.forEach(f);
-  }
-}
-
-/// Keeps track of all elements and holders.
-///
-/// This class assigns each registered element to its [LibrariesMap] (which are
-/// in bijection with [OutputUnit]s).
-///
-/// Registered holders are assigned a name.
-class Registry {
-  final Compiler _compiler;
-  final Map<String, Holder> _holdersMap = <String, Holder>{};
-  final Map<OutputUnit, LibrariesMap> _deferredLibrariesMap =
-      <OutputUnit, LibrariesMap>{};
-
-  /// Cache for the last seen output unit.
-  OutputUnit _lastOutputUnit;
-  LibrariesMap _lastLibrariesMap;
-
-  DeferredLoadTask get _deferredLoadTask => _compiler.deferredLoadTask;
-  Iterable<Holder> get holders => _holdersMap.values;
-  Iterable<LibrariesMap> get deferredLibrariesMap =>
-      _deferredLibrariesMap.values;
-
-  // Add one for the main libraries map.
-  int get librariesMapCount => _deferredLibrariesMap.length + 1;
-
-  LibrariesMap mainLibrariesMap;
-
-  Registry(this._compiler);
-
-  OutputUnit get _mainOutputUnit => _deferredLoadTask.mainOutputUnit;
-
-  LibrariesMap _mapUnitToLibrariesMap(OutputUnit targetUnit) {
-    if (targetUnit == _lastOutputUnit) return _lastLibrariesMap;
-
-    LibrariesMap result = (targetUnit == _mainOutputUnit)
-        ? mainLibrariesMap
-        : _deferredLibrariesMap[targetUnit];
-
-    assert(result != null);
-    _lastOutputUnit = targetUnit;
-    _lastLibrariesMap = result;
-    return result;
-  }
-
-  void registerOutputUnit(OutputUnit outputUnit) {
-    if (outputUnit == _mainOutputUnit) {
-      assert(mainLibrariesMap == null);
-      mainLibrariesMap =
-          new LibrariesMap.main(_deferredLoadTask.mainOutputUnit);
-    } else {
-      assert(!_deferredLibrariesMap.containsKey(outputUnit));
-      String name = outputUnit.name;
-      _deferredLibrariesMap[outputUnit] =
-          new LibrariesMap.deferred(outputUnit, name);
-    }
-  }
-
-  /// Adds all elements to their respective libraries in the correct
-  /// libraries map.
-  void registerElements(OutputUnit outputUnit, Iterable<Element> elements) {
-    LibrariesMap targetLibrariesMap = _mapUnitToLibrariesMap(outputUnit);
-    for (Element element in Elements.sortedByPosition(elements)) {
-      targetLibrariesMap.add(element.library, element);
-    }
-  }
-
-  void registerConstant(OutputUnit outputUnit, ConstantValue constantValue) {
-    // Ignore for now.
-  }
-
-  Holder registerHolder(String name) {
-    return _holdersMap.putIfAbsent(
-        name,
-        () => new Holder(name, _holdersMap.length));
-  }
-}