Optimize IntArrayToIntMap and ElementCodec.encodeHash().

pkg/analysis_server/lib/src/services/index/store/codec.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.
 
 library services.src.index.store.codec;
 
 import 'dart:collection';
 
 import 'package:analysis_server/src/services/index/index.dart';
 import 'package:analysis_server/src/services/index/store/collection.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/source.dart';
+import 'package:analyzer/src/generated/utilities_general.dart';
 
 
 /**
  * A helper that encodes/decodes [AnalysisContext]s from/to integers.
  */
 class ContextCodec {
   /**
    * A table mapping contexts to their unique indices.
    */
   Map<AnalysisContext, int> _contextToIndex =
@@ skipping 105 matching lines @@
       location.indexKeyId = index;
     } else {
       location.indexOwner = this;
       location.indexLocationId = index;
     }
     // done
     return index;
   }
 
   /**
-   * Returns an integer that corresponds to an approximated location of [element].
+   * Returns an integer that corresponds to the name of [element].
    */
   int encodeHash(Element element) {
-    List<int> path = _getLocationPathLimited(element);
-    int index = _encodePath(path);
-    return index;
+    String elementName = element.displayName;
+    int elementNameId = _stringCodec.encode(elementName);
+    LibraryElement libraryElement = element.library;
+    if (libraryElement != null) {
+      String libraryPath = libraryElement.source.fullName;
+      int libraryPathId = _stringCodec.encode(libraryPath);
+      return JenkinsSmiHash.combine(libraryPathId, elementNameId);
+    } else {
+      return elementNameId;
+    }
   }
 
   /**
    * Returns a list with the location components of the element with the
    * given encoded ID.
    */
   List<String> inspect_decodePath(int id) {
     List<int> path = _indexToPath[id];
     return _getLocationComponents(path);
   }
@@ skipping 81 matching lines @@
     } else {
       List<int> path = new List<int>.filled(length, 0);
       for (int i = 0; i < length; i++) {
         String component = components[i];
         path[i] = _stringCodec.encode(component);
       }
       return path;
     }
   }
 
-  /**
-   * Returns an approximation of the [element]'s location.
-   */
-  List<int> _getLocationPathLimited(Element element) {
-    String firstComponent;
-    {
-      LibraryElement libraryElement = element.library;
-      if (libraryElement != null) {
-        firstComponent = libraryElement.source.fullName;
-      } else {
-        firstComponent = 'null';
-      }
-    }
-    String lastComponent = element.displayName;
-    int firstId = _stringCodec.encode(firstComponent);
-    int lastId = _stringCodec.encode(lastComponent);
-    return <int>[firstId, lastId];
-  }
-
   static bool _hasLocalOffset(List<String> components) {
     for (String component in components) {
       if (component.indexOf('@') != -1) {
         return true;
       }
     }
     return false;
   }
 }
 
@@ skipping 43 matching lines @@
   int encode(String name) {
     int index = nameToIndex[name];
     if (index == null) {
       index = _indexToName.length;
       nameToIndex[name] = index;
       _indexToName.add(name);
     }
     return index;
   }
 }