dart2js OldEmitter: inline FinishClasses.

pkg/compiler/lib/src/js_emitter/old_emitter/reflection_data_parser.dart

 // Copyright (c) 2013, 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;
 
 // TODO(ahe): Share these with js_helper.dart.
 const FUNCTION_INDEX = 0;
 const NAME_INDEX = 1;
 const CALL_NAME_INDEX = 2;
 const REQUIRED_PARAMETER_INDEX = 3;
 const OPTIONAL_PARAMETER_INDEX = 4;
 const DEFAULT_ARGUMENTS_INDEX = 5;
 
 const bool VALIDATE_DATA = false;
 
-// TODO(ahe): This code should be integrated in CodeEmitterTask.finishClasses.
-jsAst.Expression getReflectionDataParser(String classesCollector,
-                                        JavaScriptBackend backend) {
+jsAst.Expression getReflectionDataParser(OldEmitter oldEmitter,
+                                         JavaScriptBackend backend) {
   Namer namer = backend.namer;
   Compiler compiler = backend.compiler;
   CodeEmitterTask emitter = backend.emitter;
 
   String metadataField = '"${namer.metadataField}"';
   String reflectableField = namer.reflectableField;
 
   // TODO(ahe): Move this string constants to namer.
   String reflectionInfoField = r'$reflectionInfo';
   String reflectionNameField = r'$reflectionName';
@@ skipping 14 matching lines @@
   jsAst.Expression staticsAccess =
       emitter.generateEmbeddedGlobalAccess(embeddedNames.STATICS);
   jsAst.Expression interceptedNamesAccess =
       emitter.generateEmbeddedGlobalAccess(embeddedNames.INTERCEPTED_NAMES);
   jsAst.Expression mangledGlobalNamesAccess =
       emitter.generateEmbeddedGlobalAccess(embeddedNames.MANGLED_GLOBAL_NAMES);
   jsAst.Expression mangledNamesAccess =
       emitter.generateEmbeddedGlobalAccess(embeddedNames.MANGLED_NAMES);
   jsAst.Expression librariesAccess =
       emitter.generateEmbeddedGlobalAccess(embeddedNames.LIBRARIES);
+  jsAst.Expression metadataAccess =
+      emitter.generateEmbeddedGlobalAccess(embeddedNames.METADATA);
 
   jsAst.Statement header = js.statement('''
 // [map] returns an object literal that V8 shouldn not try to optimize with a
 // hidden class. This prevents a potential performance problem where V8 tries
 // to build a hidden class for an object used as a hashMap.
 // It requires fewer characters to declare a variable as a parameter than
 // with `var`.
   function map(x){x=Object.create(null);x.x=0;delete x.x;return x}
 ''');
 
+  jsAst.Statement processClassData = js.statement('''{
+  function processClassData(cls, descriptor, processedClasses) {
+    var newDesc = {};
+    var previousProperty;
+    for (var property in descriptor) {
+      if (!hasOwnProperty.call(descriptor, property)) continue;
+      var firstChar = property.substring(0, 1);
+      if (property === "static") {
+        processStatics(#embeddedStatics[cls] = descriptor[property], 
+                       processedClasses);
+      } else if (firstChar === "+") {
+        mangledNames[previousProperty] = property.substring(1);
+        var flag = descriptor[property];
+        if (flag > 0)
+          descriptor[previousProperty].$reflectableField = flag;
+      } else if (firstChar === "@" && property !== "@") {
+        newDesc[property.substring(1)][$metadataField] = descriptor[property];
+      } else if (firstChar === "*") {
+        newDesc[previousProperty].$defaultValuesField = descriptor[property];
+        var optionalMethods = newDesc.$methodsWithOptionalArgumentsField;
+        if (!optionalMethods) {
+          newDesc.$methodsWithOptionalArgumentsField = optionalMethods={}
+        }
+        optionalMethods[property] = previousProperty;
+      } else {
+        var elem = descriptor[property];
+        if (property !== "${namer.classDescriptorProperty}" &&
+            elem != null &&
+            elem.constructor === Array &&
+            property !== "<>") {
+          addStubs(newDesc, elem, property, false, descriptor, []);
+        } else {
+          newDesc[previousProperty = property] = elem;
+        }
+      }
+    }
+
+    /* The 'fields' are either a constructor function or a
+     * string encoding fields, constructor and superclass. Gets the
+     * superclass and fields in the format
+     *   'Super;field1,field2'
+     * from the CLASS_DESCRIPTOR_PROPERTY property on the descriptor.
+     */
+    var classData = newDesc["${namer.classDescriptorProperty}"],
+        split, supr, fields = classData;
+
+    if (#hasRetainedMetadata)
+      if (typeof classData == "object" &&
+          classData instanceof Array) {
+        classData = fields = classData[0];
+      }
+    // ${ClassBuilder.fieldEncodingDescription}.
+    var s = fields.split(";");
+    fields = s[1] == "" ? [] : s[1].split(",");
+    supr = s[0];
+    // ${ClassBuilder.functionTypeEncodingDescription}.
+    split = supr.split(":");
+    if (split.length == 2) {
+      supr = split[0];
+      var functionSignature = split[1];
+      if (functionSignature)
+        newDesc.${namer.operatorSignature} = function(s) {
+          return function() {
+            return #metadata[s];
+          };
+        }(functionSignature);
+    }
+
+    if (supr) processedClasses.pending[cls] = supr;
+    if (#notInCspMode) {
+      processedClasses.combinedConstructorFunction += defineClass(cls, fields);
+      processedClasses.constructorsList.push(cls);
+    }
+    processedClasses.collected[cls] = [globalObject, newDesc];
+    classes.push(cls);
+  }
+}''', {'embeddedStatics': staticsAccess,
+       'hasRetainedMetadata': backend.hasRetainedMetadata,
+       'metadata': metadataAccess,
+       'notInCspMode': !compiler.useContentSecurityPolicy});
+
   jsAst.Statement processStatics = js.statement('''
-    function processStatics(descriptor) {
+    function processStatics(descriptor, processedClasses) {
       for (var property in descriptor) {
         if (!hasOwnProperty.call(descriptor, property)) continue;
         if (property === "${namer.classDescriptorProperty}") continue;
         var element = descriptor[property];
         var firstChar = property.substring(0, 1);
         var previousProperty;
         if (firstChar === "+") {
           mangledGlobalNames[previousProperty] = property.substring(1);
           var flag = descriptor[property];
           if (flag > 0)
             descriptor[previousProperty].$reflectableField = flag;
           if (element && element.length)
-            #[previousProperty] = element;  // embedded typeInformation.
+            #typeInformation[previousProperty] = element;
         } else if (firstChar === "@") {
           property = property.substring(1);
           ${namer.currentIsolate}[property][$metadataField] = element;
         } else if (firstChar === "*") {
           globalObject[previousProperty].$defaultValuesField = element;
           var optionalMethods = descriptor.$methodsWithOptionalArgumentsField;
           if (!optionalMethods) {
             descriptor.$methodsWithOptionalArgumentsField = optionalMethods = {}
           }
           optionalMethods[property] = previousProperty;
         } else if (typeof element === "function") {
           globalObject[previousProperty = property] = element;
           functions.push(property);
-          #[property] = element;  // embedded globalFunctions.
+          #globalFunctions[property] = element;
         } else if (element.constructor === Array) {
           addStubs(globalObject, element, property,
                    true, descriptor, functions);
         } else {
-          previousProperty = property;
-          var newDesc = {};
-          var previousProp;
-          for (var prop in element) {
-            if (!hasOwnProperty.call(element, prop)) continue;
-            firstChar = prop.substring(0, 1);
-            if (prop === "static") {
-              processStatics(#[property] = element[prop]);  // embedded statics.
-            } else if (firstChar === "+") {
-              mangledNames[previousProp] = prop.substring(1);
-              var flag = element[prop];
-              if (flag > 0)
-                element[previousProp].$reflectableField = flag;
-            } else if (firstChar === "@" && prop !== "@") {
-              newDesc[prop.substring(1)][$metadataField] = element[prop];
-            } else if (firstChar === "*") {
-              newDesc[previousProp].$defaultValuesField = element[prop];
-              var optionalMethods = newDesc.$methodsWithOptionalArgumentsField;
-              if (!optionalMethods) {
-                newDesc.$methodsWithOptionalArgumentsField = optionalMethods={}
-              }
-              optionalMethods[prop] = previousProp;
-            } else {
-              var elem = element[prop];
-              if (prop !== "${namer.classDescriptorProperty}" &&
-                  elem != null &&
-                  elem.constructor === Array &&
-                  prop !== "<>") {
-                addStubs(newDesc, elem, prop, false, element, []);
-              } else {
-                newDesc[previousProp = prop] = elem;
-              }
-            }
+          // We will not enter this case if no classes are defined.
+          if (#hasClasses) {
+            previousProperty = property;
+            processClassData(property, element, processedClasses);
           }
-          $classesCollector[property] = [globalObject, newDesc];
-          classes.push(property);
         }
       }
     }
-''', [typeInformationAccess, globalFunctionsAccess, staticsAccess]);
+''', {'typeInformation': typeInformationAccess,
+      'globalFunctions': globalFunctionsAccess,
+      'hasClasses': oldEmitter.hasClasses});
 
 
   /**
    * See [dart2js.js_emitter.ContainerBuilder.addMemberMethod] for format of
    * [array].
    */
   jsAst.Statement addStubs = js.statement('''
   function addStubs(descriptor, array, name, isStatic,
                     originalDescriptor, functions) {
     var index = $FUNCTION_INDEX, alias = array[index], f;
@@ skipping 27 matching lines @@
     var isAccessor = (requiredParameterInfo & 1) === 1;
     var isSetter = requiredParameterInfo === 3;
     var isGetter = requiredParameterInfo === 1;
     var optionalParameterInfo = ${readInt("array", "1")};
     var optionalParameterCount = optionalParameterInfo >> 1;
     var optionalParametersAreNamed = (optionalParameterInfo & 1) === 1;
     var isIntercepted =
            requiredParameterCount + optionalParameterCount != funcs[0].length;
     var functionTypeIndex = ${readFunctionType("array", "2")};
     var unmangledNameIndex = $unmangledNameIndex;
     var isReflectable = array.length > unmangledNameIndex;

[floitsch, 2014/12/29 18:00:22]

for a different CL:
inline this boolean and change the if in line 252 to:
if (#isReflectionEnabled) {
  var isReflectable = array.length > unmangledNameIndex;
  if (isReflectable) {
    ...
  }
}

[zarah, 2014/12/30 14:02:44]

Acknowledged.

 
     if (getterStubName) {
       f = tearOff(funcs, array, isStatic, name, isIntercepted);
       descriptor[name].\$getter = f;
       f.\$getterStub = true;
       // Used to create an isolate using spawnFunction.
       if (isStatic) #[name] = f;  // embedded globalFunctions.
       originalDescriptor[getterStubName] = descriptor[getterStubName] = f;
       funcs.push(f);
       if (getterStubName) functions.push(getterStubName);
@@ skipping 25 matching lines @@
       if (optionalParameterCount) descriptor[unmangledName + "*"] = funcs[0];
     }
   }
 ''', [globalFunctionsAccess, interceptedNamesAccess,
       mangledGlobalNamesAccess, mangledNamesAccess]);
 
   List<jsAst.Statement> tearOffCode = buildTearOffCode(backend);
 
   jsAst.Statement init = js.statement('''{
   var functionCounter = 0;
-  if (!#) # = [];  // embedded libraries.
-  if (!#) # = map();  // embedded mangledNames.
-  if (!#) # = map();  // embedded mangledGlobalNames.
-  if (!#) # = map();  // embedded statics.
-  if (!#) # = map();  // embedded typeInformation.
-  if (!#) # = map();  // embedded globalFunctions.
-  if (!#) # = map();  // embedded interceptedNames.
-  var libraries = #;  // embeded libraries.
-  var mangledNames = #;  // embedded mangledNames.
-  var mangledGlobalNames = #;  // embedded mangledGlobalNames.
+  if (!#libraries) #libraries = [];
+  if (!#mangledNames) #mangledNames = map();
+  if (!#mangledGlobalNames) #mangledGlobalNames = map();
+  if (!#statics) #statics = map();
+  if (!#typeInformation) #typeInformation = map(); 
+  if (!#globalFunctions) #globalFunctions = map();
+  if (!#interceptedNames) #interceptedNames = map();
+  var libraries = #libraries;
+  var mangledNames = #mangledNames;
+  var mangledGlobalNames = #mangledGlobalNames;
   var hasOwnProperty = Object.prototype.hasOwnProperty;
   var length = reflectionData.length;
+  var processedClasses = Object.create(null);
+  processedClasses.collected = Object.create(null);
+  processedClasses.pending = Object.create(null);
+  if (#notInCspMode) {
+    processedClasses.constructorsList = [];
+    processedClasses.combinedConstructorFunction =

[floitsch, 2014/12/29 18:00:22]

Add comment, that the variable will be changed for every class.

[zarah, 2014/12/30 14:02:44]

Done.

+        "function \$reflectable(fn){fn.$reflectableField=1;return fn};\\n"+
+        "var \$desc;\\n";
+  }
   for (var i = 0; i < length; i++) {
     var data = reflectionData[i];
 
 // [data] contains these elements:
 // 0. The library name (not unique).
 // 1. The library URI (unique).
 // 2. A function returning the metadata associated with this library.
 // 3. The global object to use for this library.
 // 4. An object literal listing the members of the library.
 // 5. This element is optional and if present it is true and signals that this
 // library is the root library (see dart:mirrors IsolateMirror.rootLibrary).
 //
 // The entries of [data] are built in [assembleProgram] above.
 
     var name = data[0];
     var uri = data[1];
     var metadata = data[2];
     var globalObject = data[3];
     var descriptor = data[4];
     var isRoot = !!data[5];
     var fields = descriptor && descriptor["${namer.classDescriptorProperty}"];
     if (fields instanceof Array) fields = fields[0];
     var classes = [];
     var functions = [];
-    processStatics(descriptor);
+    processStatics(descriptor, processedClasses);
     libraries.push([name, uri, classes, functions, metadata, fields, isRoot,
                     globalObject]);
   }
-}''', [librariesAccess, librariesAccess,
-       mangledNamesAccess, mangledNamesAccess,
-       mangledGlobalNamesAccess, mangledGlobalNamesAccess,
-       staticsAccess, staticsAccess,
-       typeInformationAccess, typeInformationAccess,
-       globalFunctionsAccess, globalFunctionsAccess,
-       interceptedNamesAccess, interceptedNamesAccess,
-       librariesAccess,
-       mangledNamesAccess,
-       mangledGlobalNamesAccess]);
+    if (#hasClasses) finishClasses(processedClasses);

[floitsch, 2014/12/29 18:00:22]

Indentation seems off.

[zarah, 2014/12/30 14:02:44]

Done.

+}''',{'libraries': librariesAccess,
+      'mangledNames': mangledNamesAccess,
+      'mangledGlobalNames': mangledGlobalNamesAccess,
+      'statics': staticsAccess,
+      'typeInformation': typeInformationAccess,
+      'globalFunctions': globalFunctionsAccess,
+      'interceptedNames': interceptedNamesAccess,
+      'notInCspMode': !compiler.useContentSecurityPolicy,
+      'hasClasses': oldEmitter.hasClasses});
+
+  jsAst.Expression allClassesAccess =
+      emitter.generateEmbeddedGlobalAccess(embeddedNames.ALL_CLASSES);
+
+  String specProperty = '"${namer.nativeSpecProperty}"';  // "%"
+
+  // Class descriptions are collected in a JS object.
+  // 'finishClasses' takes all collected descriptions and sets up
+  // the prototype.
+  // Once set up, the constructors prototype field satisfy:
+  //  - it contains all (local) members.
+  //  - its internal prototype (__proto__) points to the superclass'
+  //    prototype field.
+  //  - the prototype's constructor field points to the JavaScript
+  //    constructor.
+  // For engines where we have access to the '__proto__' we can manipulate
+  // the object literal directly. For other engines we have to create a new
+  // object and copy over the members.
+  jsAst.Statement finishClasses = js.statement('''{
+  function finishClasses(processedClasses) {
+    if (#debugFastObjects)
+      print("Number of classes: " +
+            Object.getOwnPropertyNames(processedClasses.collected).length);
+
+    var allClasses = #allClasses;
+
+    if (#inCspMode) {
+      constructors = dart_precompiled(processedClasses.collected);
+    }
+
+    if (#notInCspMode) {
+      processedClasses.combinedConstructorFunction +=
+        "return [\\n" + processedClasses.constructorsList.join(",\\n  ") + 
+        "\\n]";
+     var constructors =

[floitsch, 2014/12/29 18:00:22]

Please avoid big code moves with code changes.
It's extremely hard to see what part has just been copied and what has been
changed.

[zarah, 2014/12/30 14:02:44]

Acknowledged.

+       new Function("\$collectedClasses", 
+           processedClasses.combinedConstructorFunction)
+               (processedClasses.collected);
+      processedClasses.combinedConstructorFunction = null;
+    }
+
+    for (var i = 0; i < constructors.length; i++) {
+      var constructor = constructors[i];
+      var cls = constructor.name;
+      var desc = processedClasses.collected[cls];
+      var globalObject = \$;
+      if (desc instanceof Array) {
+        globalObject = desc[0] || isolateProperties;
+        desc = desc[1];
+      }
+      if (#isTreeShakingDisabled)
+        constructor["${namer.metadataField}"] = desc;
+      allClasses[cls] = constructor;
+      globalObject[cls] = constructor;
+    }
+    constructors = null;
+
+    #finishClassFunction;
+
+    #trivialNsmHandlers;
+
+    for (var cls in processedClasses.pending) finishClass(cls);
+  }
+}''', {'allClasses': allClassesAccess,
+       'debugFastObjects': DEBUG_FAST_OBJECTS,
+       'isTreeShakingDisabled': backend.isTreeShakingDisabled,
+       'finishClassFunction': oldEmitter.buildFinishClass(),
+       'trivialNsmHandlers': oldEmitter.buildTrivialNsmHandlers(),
+       'inCspMode': compiler.useContentSecurityPolicy,
+       'notInCspMode': !compiler.useContentSecurityPolicy});
 
   List<jsAst.Statement> incrementalSupport = <jsAst.Statement>[];
   if (compiler.hasIncrementalSupport) {
     incrementalSupport.add(
         js.statement(
             r'self.$dart_unsafe_eval.addStubs = addStubs;'));
   }
 
   return js('''
 (function (reflectionData) {
   "use strict";
   #header;

[floitsch, 2014/12/29 18:00:22]

Different CL:
I wonder if we shouldn't just inline all this holes.
I don't think there is a lot of value in assigning them to a temporary variable
first. To be discussed.

[zarah, 2014/12/30 14:02:44]

Acknowledged.

+  if (#hasClasses) {
+    #defineClass;
+    #inheritFrom;
+    #finishClasses;
+    #processClassData;
+  }
   #processStatics;
   #addStubs;
   #tearOffCode;
   #incrementalSupport;
   #init;
 })''', {
       'header': header,
+      'defineClass': oldEmitter.defineClassFunction,
+      'inheritFrom': oldEmitter.buildInheritFrom(),
+      'processClassData': processClassData,
       'processStatics': processStatics,
       'incrementalSupport': incrementalSupport,
       'addStubs': addStubs,
       'tearOffCode': tearOffCode,
-      'init': init});
+      'init': init,
+      'finishClasses': finishClasses,
+      'hasClasses': oldEmitter.hasClasses});
 }
 
 
 List<jsAst.Statement> buildTearOffCode(JavaScriptBackend backend) {
   Namer namer = backend.namer;
   Compiler compiler = backend.compiler;
 
   Element closureFromTearOff = backend.findHelper('closureFromTearOff');
   String tearOffAccessText;
   jsAst.Expression tearOffAccessExpression;
@@ skipping 101 matching lines @@
 (function() {
   var result = $array[$index];
   if ($check) {
     throw new Error(
         name + ": expected value of type \'$type\' at index " + ($index) +
         " but got " + (typeof result));
   }
   return result;
 })()''';
 }