Optimize dartium dart:html bindings so real world application performance is acceptable. Improves d…

tools/dom/scripts/generate_blink_file.py

Index: tools/dom/scripts/generate_blink_file.py
diff --git a/tools/dom/scripts/generate_blink_file.py b/tools/dom/scripts/generate_blink_file.py
index 6f274da35b6ae30b6cf35c5375cb3db6e271a321..4beb0a56fa4ce7635874a88d5b07860222268252 100644
--- a/tools/dom/scripts/generate_blink_file.py
+++ b/tools/dom/scripts/generate_blink_file.py
@@ -7,9 +7,85 @@
 """Generates sdk/lib/_blink/dartium/_blink_dartium.dart file."""
 
 import os
-
+from sets import Set
 from generator import AnalyzeOperation, AnalyzeConstructor
 
+# This is list of all methods with native c++ implementations
+# If performing a dartium merge, the best practice is to comment out this list,
+# ensure everything runs, and then uncomment this list which might possibly
+# introduce breaking changes due to changes to these method signatures.
+_js_custom_members = Set([
+    'Document.createElement',
+    'Element.id',
+    'Element.tagName',
+    'Element.className',
+    'Element.setAttribute',
+    'Element.getAttribute',
+    # Consider adding this method so there is a fast path to access only
+    # element children.
+    # 'NonDocumentTypeChildNode.nextElementSibling',
+    'Node.appendChild', # actually not removed, just native implementation.
+    'Node.cloneNode',
+    'Node.insertBefore',    
+    'Node.lastChild',
+    'Node.firstChild',
+    'Node.parentElement',
+    'Node.parentNode',
+    'Node.childNodes',
+    'Node.removeChild',
+    'Node.contains',
+    'Node.nextSibling',
+    'Node.previousSibling',
+    'ChildNode.remove',
+    'Document.createTextNode',
+    'Window.location',
+    'Location.href',
+    'Node.querySelector',
+
+    'HTMLElement.hidden',
+    'HTMLElement.style',
+    'Element.attributes',
+    'Window.innerWidth',
+
+    'NodeList.length',
+    'NodeList.item',
+    'ParentNode.children',
+    'ParentNode.firstElementChild',
+    'ParentNode.lastElementChild',
+    'Event.target',
+    'MouseEvent.clientY',
+    'MouseEvent.clientX',
+
+    'Node.nodeType',
+    'Node.textContent',
+    
+    'HTMLCollection.length',
+    'HTMLCollection.item',
+    'Node.lastElementChild',
+    'Node.firstElementChild',
+    'HTMLElement_tabIndex',
+
+    'Element.clientWidth',
+    'Element.clientHeight',
+    'Document.body',
+    'Element.removeAttribute',
+    'Element.getBoundingClientRect',
+    'CSSStyleDeclaration.getPropertyValue',
+    'CSSStyleDeclaration.setProperty',
+    'CSSStyleDeclaration.__propertyQuery__',
+
+    # TODO(jacobr): consider implementing these methods as well as they show
+    # up in benchmarks for some sample applications.
+    #'Document.createEvent',
+    #'Document.initEvent',
+    #'EventTarget.dispatchEvent',
+     ])
+
+# Uncomment out this line  to short circuited native methods and run all of
+# dart:html through JS interop except for createElement which is slightly more
+# tightly natively wired.
+# _js_custom_members = Set([])
+
 HEADER = """/* 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.
@@ -50,13 +126,14 @@ class Blink_Utils {
 
   static register(document, tag, customType, extendsTagName) native "Utils_register";
 
-  static createElement(document, tagName) native "Utils_createElement";
-
-  static constructElement(element_type, jsObject) native "Utils_constructor_create";
+  // Defines an interceptor if there is an appropriate JavaScript prototype to define it on.
+  // In any case, returns a typed JS wrapper compatibile with dart:html and the new
+  // typed JS Interop.
+  static defineInterceptorCustomElement(jsObject, Type type) native "Utils_defineInterceptorCustomElement";
+  static setInstanceInterceptor(o, Type type, {bool customElement: false}) native "Utils_setInstanceInterceptor";
 
+  // This method will throw if the element isn't actually a real Element.
   static initializeCustomElement(element) native "Utils_initializeCustomElement";
-
-  static changeElementWrapper(element, type) native "Utils_changeElementWrapper";
 }
 
 class Blink_DOMWindowCrossFrame {
@@ -106,9 +183,63 @@ class Blink_DOMStringMap {
 }
 
 // Calls through JsNative but returns DomException instead of error strings.
+class Stats {
+  Stats(this.name) {
+    counts = new Map<String, int>();
+  }
+
+  String name;
+  Map<String, int> counts;
+  clear() {
+    counts.clear();
+  }
+
+  track(String v) {
+    counts[v] = counts.putIfAbsent(v, ()=> 0) + 1;
+  }
+  toString() {
+    StringBuffer sb = new StringBuffer();
+    sb.write('================');
+    sb.write('$name ${counts.length}');
+    var keys = counts.keys.toList();
+    keys.sort((a,b) => counts[b].compareTo(counts[a]));
+    for (var key in keys) {
+      print("$key => ${counts[key]}");
+    }
+    sb.write('---------------');
+    sb.write('================');
+    return sb;
+  }
+}
+
+bool TRACK_STATS = true;
+dumpStats() {
+  print("------------ STATS ----------------");
+  print(Blink_JsNative_DomException.getPropertyStats.toString()); 
+  print(Blink_JsNative_DomException.setPropertyStats.toString());
+  print(Blink_JsNative_DomException.callMethodStats.toString());
+  print(Blink_JsNative_DomException.constructorStats.toString());
+  print("-----------------------------------");
+}
+
+clearStats() {
+  Blink_JsNative_DomException.getPropertyStats.clear();
+  Blink_JsNative_DomException.setPropertyStats.clear();
+  Blink_JsNative_DomException.callMethodStats.clear();  
+  Blink_JsNative_DomException.constructorStats.clear();  
+}
+
 class Blink_JsNative_DomException {
-  static getProperty(js.JsObject o, name) {
+  static var getPropertyStats = new Stats('get property');
+  static var setPropertyStats = new Stats('set property');
+  static var callMethodStats = new Stats('call method');
+  static var constructorStats = new Stats('constructor');
+
+  static var constructors = new Map<String, dynamic>();
+
+  static getProperty(o, String name) {
     try {
+      if (TRACK_STATS) getPropertyStats.track(name);
       return js.JsNative.getProperty(o, name);
     } catch (e) {
       // Re-throw any errors (returned as a string) as a DomException.
@@ -116,8 +247,51 @@ class Blink_JsNative_DomException {
     }
   }
 
-  static callMethod(js.JsObject o, String method, List args) {
+  static propertyQuery(o, String name) {
     try {
+      if (TRACK_STATS) getPropertyStats.track('__propertyQuery__');
+      return js.JsNative.getProperty(o, name);
+    } catch (e) {
+      // Re-throw any errors (returned as a string) as a DomException.
+      throw new DomException.jsInterop(e);
+    }
+  }
+
+  static callConstructor0(String name) {
+    try {
+      if (TRACK_STATS) constructorStats.track(name);
+      var constructor = constructors.putIfAbsent(name, () => js.context[name]);
+      return js.JsNative.callConstructor0(constructor);
+    } catch (e) {
+      // Re-throw any errors (returned as a string) as a DomException.
+      throw new DomException.jsInterop(e);
+    }
+  }
+
+  static callConstructor(String name, List args) {
+    try {
+      if (TRACK_STATS) constructorStats.track(name);
+      var constructor = constructors.putIfAbsent(name, () => js.context[name]);
+      return js.JsNative.callConstructor(constructor, args);
+    } catch (e) {
+      // Re-throw any errors (returned as a string) as a DomException.
+      throw new DomException.jsInterop(e);
+    }
+  }
+
+  static setProperty(o, String name, value) {
+    try {
+      if (TRACK_STATS) setPropertyStats.track(name);
+      return js.JsNative.setProperty(o, name, value);
+    } catch (e) {
+      // Re-throw any errors (returned as a string) as a DomException.
+      throw new DomException.jsInterop(e);
+    }
+  }
+
+  static callMethod(o, String method, List args) {
+    try {
+      if (TRACK_STATS) callMethodStats.track(method);
       return js.JsNative.callMethod(o, method, args);
     } catch (e) {
       // Re-throw any errors (returned as a string) as a DomException.
@@ -137,38 +311,73 @@ CLASS_DEFINITION_EXTENDS = """class Blink%s extends Blink%s {
 """
 
 #(interface_name)
-CONSTRUCTOR_0 = '  constructorCallback_0_() => new js.JsObject(Blink_JsNative_DomException.getProperty(js.context, "%s"), []);\n\n'
+
+#
+CONSTRUCTOR_0 = ['  constructorCallback_0_()',
+                 ' => Blink_JsNative_DomException.callConstructor0("%s");\n\n',
+                 ' native "Blink_Constructor_%s";\n\n']
 
 #(argument_count, arguments, interface_name, arguments)
-CONSTRUCTOR_ARGS = '  constructorCallback_%s_(%s) => new js.JsObject(Blink_JsNative_DomException.getProperty(js.context, "%s"), [%s]);\n\n'
+CONSTRUCTOR_ARGS = ['  constructorCallback_%s_(%s)',
+   ' => Blink_JsNative_DomException.callConstructor("%s", [%s]);\n\n',
+   ' native "Blink_Constructor_Args_%s" /* %s */;\n\n']
 
 #(attribute_name, attribute_name)
-ATTRIBUTE_GETTER = '  %s_Getter_(mthis) => Blink_JsNative_DomException.getProperty(mthis, "%s");\n\n'
-ATTRIBUTE_SETTER = '  %s_Setter_(mthis, __arg_0) => mthis["%s"] = __arg_0;\n\n'
+ATTRIBUTE_GETTER = ['  %s_Getter_(mthis)',
+                    ' => Blink_JsNative_DomException.getProperty(mthis /* %s */, "%s");\n\n',
+                    ' native "Blink_Getter_%s_%s";\n\n'
+                    ]
+
+ATTRIBUTE_SETTER = ['  %s_Setter_(mthis, __arg_0)',
+                    ' => Blink_JsNative_DomException.setProperty(mthis /* %s */, "%s", __arg_0);\n\n',
+                    ' native "Blink_Setter_%s_%s";\n\n'
+                    ]
 
 #(operation_name, operationName)
-OPERATION_0 = '  %s_Callback_0_(mthis) => Blink_JsNative_DomException.callMethod(mthis, "%s", []);\n\n'
+OPERATION_0 = ['  %s_Callback_0_(mthis)',
+               ' => Blink_JsNative_DomException.callMethod(mthis /* %s */, "%s", []);\n\n',
+               ' native "Blink_Operation_0_%s_%s";\n\n'
+               ]
 
 # getter, setter, deleter and propertyQuery code
-OPERATION_1 = '  $%s_Callback_1_(mthis, __arg_0) => Blink_JsNative_DomException.callMethod(mthis, "%s", [__arg_0]);\n\n'
-OPERATION_2 = '  $%s_Callback_2_(mthis, __arg_0, __arg_1) => Blink_JsNative_DomException.callMethod(mthis, "%s", [__arg_0, __arg_1]);\n\n'
-OPERATION_PQ = '  $%s_Callback_1_(mthis, __arg_0) => mthis[__arg_0];\n\n'
+OPERATION_1 = ['  $%s_Callback_1_(mthis, __arg_0)',
+               ' => Blink_JsNative_DomException.callMethod(mthis /* %s */, "%s", [__arg_0]);\n\n',
+               ' native "Blink_Operation_1_%s_%s";\n\n'
+               ]
+
+OPERATION_2 = ['  $%s_Callback_2_(mthis, __arg_0, __arg_1)',
+               ' => Blink_JsNative_DomException.callMethod(mthis /* %s */, "%s", [__arg_0, __arg_1]);\n\n',
+               ' native "Blink_Operation_2_%s_%s";\n\n']
+
+OPERATION_PQ = ['  $%s_Callback_1_(mthis, __arg_0)',
+                ' => Blink_JsNative_DomException.propertyQuery(mthis, __arg_0); /* %s */ \n\n',
+                ' native "Blink_Operation_PQ_%s";\n\n']
 
 #(operation_name, argument_count, arguments, operation_name, arguments)
 ARGUMENT_NUM = "__arg_%s"
-OPERATION_ARGS = '  %s_Callback_%s_(mthis, %s) => Blink_JsNative_DomException.callMethod(mthis, "%s", [%s]);\n\n'
+OPERATION_ARGS = ['  %s_Callback_%s_(mthis, %s)',
+                  ' => Blink_JsNative_DomException.callMethod(mthis /* %s */, "%s", [%s]);\n\n',
+                  ' native "Blink_Operation_%s_%s"; /* %s */\n\n']
+
+
 
 # get class property to make static call.
 CLASS_STATIC = 'Blink_JsNative_DomException.getProperty(js.context, "%s")'
 
 # name, classname_getproperty, name
-STATIC_ATTRIBUTE_GETTER = '  %s_Getter_() => Blink_JsNative_DomException.getProperty(%s, "%s");\n\n'
+STATIC_ATTRIBUTE_GETTER = ['  %s_Getter_()',
+                           ' => Blink_JsNative_DomException.getProperty(%s /* %s */, "%s");\n\n',
+                           ' /* %s */ native "Blink_Static_getter_%s_%s"']
 
 # name, classname_getproperty, name
-STATIC_OPERATION_0 = '  %s_Callback_0_() => Blink_JsNative_DomException.callMethod(%s, "%s", []);\n\n'
+STATIC_OPERATION_0 = ['  %s_Callback_0_()',
+                      ' => Blink_JsNative_DomException.callMethod(%s /* %s */, "%s", []);\n\n',
+                      ' /* %s */ native "Blink_Static_Operation_0_%s_%s']
 
 # name, argsCount, args, classname_getproperty, name, args
-STATIC_OPERATION_ARGS = '  %s_Callback_%s_(%s) => Blink_JsNative_DomException.callMethod(%s, "%s", [%s]);\n\n'
+STATIC_OPERATION_ARGS = ['  %s_Callback_%s_(%s)',
+                         ' => Blink_JsNative_DomException.callMethod(%s /* %s */, "%s", [%s]);\n\n',
+                         ' /* %s */ native "Blink_Static_Operations_%s_%s" /* %s */ \n\n']
 
 CLASS_DEFINITION_END = """}
 
@@ -197,6 +406,27 @@ constructor_renames = {
 def rename_constructor(name):
   return constructor_renames[name] if name in constructor_renames else name
 
+
+def _Find_Match(interface_id, member, member_prefix, candidates):
+  member_name = interface_id + '.' + member
+  if member_name in candidates:
+    return member_name
+  member_name = interface_id + '.' + member_prefix + member
+  if member_name in candidates:
+    return member_name
+  member_name = interface_id + '.*'
+  if member_name in candidates:
+    return member_name
+
+def _Is_Native(interface, member):
+  return _Find_Match(interface, member, '', _js_custom_members)
+
+def Select_Stub(template, is_native):
+  if is_native:
+    return template[0] + template[2]
+  else:
+    return template[0] + template[1]
+
 def Generate_Blink(output_dir, database, type_registry):
   blink_filename = os.path.join(output_dir, '_blink_dartium.dart')
   blink_file = open(blink_filename, 'w')
@@ -226,7 +456,7 @@ def Generate_Blink(output_dir, database, type_registry):
       _Emit_Blink_Constructors(blink_file, analyzed_constructors)
     elif 'Constructor' in interface.ext_attrs:
       # Zero parameter constructor.
-      blink_file.write(CONSTRUCTOR_0 % rename_constructor(name))
+      blink_file.write(Select_Stub(CONSTRUCTOR_0, _Is_Native(name, 'constructor')) % rename_constructor(name))
 
     _Process_Attributes(blink_file, interface, interface.attributes)
     _Process_Operations(blink_file, interface, interface.operations)
@@ -250,27 +480,29 @@ def _Emit_Blink_Constructors(blink_file, analyzed_constructors):
 
   for callback_index in range(arg_min_count, arg_max_count):
     if callback_index == 0:
-      blink_file.write(CONSTRUCTOR_0 % (rename_constructor(name)))
+      blink_file.write(Select_Stub(CONSTRUCTOR_0, _Is_Native(name, 'constructor')) % (rename_constructor(name)))
     else:
       arguments = []
       for i in range(0, callback_index):
         arguments.append(ARGUMENT_NUM % i)
       argument_list = ', '.join(arguments)
-      blink_file.write(CONSTRUCTOR_ARGS % (callback_index, argument_list, rename_constructor(name), argument_list))
+      blink_file.write(
+        Select_Stub(CONSTRUCTOR_ARGS, _Is_Native(name, 'constructor')) % (callback_index, argument_list, rename_constructor(name), argument_list))
 
 def _Process_Attributes(blink_file, interface, attributes):
   # Emit an interface's attributes and operations.
   for attribute in sorted(attributes, ConstantOutputOrder):
     name = attribute.id
+    is_native = _Is_Native(interface.id, name)
     if attribute.is_read_only:
       if attribute.is_static:
         class_property = CLASS_STATIC % interface.id
-        blink_file.write(STATIC_ATTRIBUTE_GETTER % (name, class_property, name))
+        blink_file.write(Select_Stub(STATIC_ATTRIBUTE_GETTER, is_native) % (name, class_property, interface.id, name))
       else:
-        blink_file.write(ATTRIBUTE_GETTER % (name, name))
+        blink_file.write(Select_Stub(ATTRIBUTE_GETTER, is_native) % (name, interface.id, name))
     else:
-      blink_file.write(ATTRIBUTE_GETTER % (name, name))
-      blink_file.write(ATTRIBUTE_SETTER % (name, name))
+      blink_file.write(Select_Stub(ATTRIBUTE_GETTER, is_native) % (name, interface.id, name))
+      blink_file.write(Select_Stub(ATTRIBUTE_SETTER, is_native) % (name, interface.id, name))
 
 def _Process_Operations(blink_file, interface, operations):
   analyzeOperations = []
@@ -292,6 +524,7 @@ def _Emit_Blink_Operation(blink_file, interface, analyzeOperations):
   analyzed = AnalyzeOperation(interface, analyzeOperations)
   (arg_min_count, arg_max_count) = generate_parameter_entries(analyzed.param_infos)
   name = analyzed.js_name
+  is_native = _Is_Native(interface.id, name)
 
   operation = analyzeOperations[0]
   if (name.startswith('__') and \
@@ -299,13 +532,13 @@ def _Emit_Blink_Operation(blink_file, interface, analyzeOperations):
        'setter' in operation.specials or \
        'deleter' in operation.specials)):
     if name == '__propertyQuery__':
-      blink_file.write(OPERATION_PQ % (name))
+      blink_file.write(Select_Stub(OPERATION_PQ, is_native) % (name, interface.id))
     else:
       arg_min_count = arg_max_count
       if arg_max_count == 2:
-        blink_file.write(OPERATION_1 % (name, name))
+        blink_file.write(Select_Stub(OPERATION_1, is_native) % (name, interface.id, name))
       elif arg_max_count == 3:
-        blink_file.write(OPERATION_2 % (name, name))
+        blink_file.write(Select_Stub(OPERATION_2, is_native) % (name, interface.id, name))
       else:
         print "FATAL ERROR: _blink emitter operator %s.%s" % (interface.id, name)
         exit
@@ -316,9 +549,9 @@ def _Emit_Blink_Operation(blink_file, interface, analyzeOperations):
     if callback_index == 0:
       if operation.is_static:
         class_property = CLASS_STATIC % interface.id
-        blink_file.write(STATIC_OPERATION_0 % (name, class_property, name))
+        blink_file.write(Select_Stub(STATIC_OPERATION_0, is_native) % (name, class_property, interface.id, name))
       else:
-        blink_file.write(OPERATION_0 % (name, name))
+        blink_file.write(Select_Stub(OPERATION_0, is_native) % (name, interface.id, name))
     else:
       arguments = []
       for i in range(0, callback_index):
@@ -326,6 +559,6 @@ def _Emit_Blink_Operation(blink_file, interface, analyzeOperations):
       argument_list = ', '.join(arguments)
       if operation.is_static:
         class_property = CLASS_STATIC % interface.id
-        blink_file.write(STATIC_OPERATION_ARGS % (name, callback_index, argument_list, class_property, name, argument_list))
+        blink_file.write(Select_Stub(STATIC_OPERATION_ARGS, is_native) % (name, callback_index, argument_list, class_property, interface.id, name, argument_list))
       else:
-        blink_file.write(OPERATION_ARGS % (name, callback_index, argument_list, name, argument_list))
+        blink_file.write(Select_Stub(OPERATION_ARGS, is_native) % (name, callback_index, argument_list, interface.id, name, argument_list))