dart2js: First part of native support in the new emitter.

pkg/compiler/lib/src/js_emitter/new_emitter/model_emitter.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 dart2js.new_js_emitter.model_emitter;
 
 import '../../dart2jslib.dart' show Compiler;
 import '../../js/js.dart' as js;
 import '../../js_backend/js_backend.dart' show
     JavaScriptBackend,
     Namer,
     ConstantEmitter;
 
 import 'package:_internal/compiler/js_lib/shared/embedded_names.dart' show
     DEFERRED_LIBRARY_URIS,
     DEFERRED_LIBRARY_HASHES,
     INITIALIZE_LOADED_HUNK,
     IS_HUNK_LOADED;
 
+import '../js_emitter.dart' show NativeGenerator;
 import '../model.dart';
 
 class ModelEmitter {
   final Compiler compiler;
   final Namer namer;
   final ConstantEmitter constantEmitter;
 
   JavaScriptBackend get backend => compiler.backend;
 
   /// For deferred loading we communicate the initializers via this global var.
   static const String deferredInitializersGlobal =
       r"$__dart_deferred_initializers__";
 
   static const String deferredExtension = "part.js";
 
   ModelEmitter(Compiler compiler, Namer namer)
       : this.compiler = compiler,
         this.namer = namer,
         constantEmitter =
             new ConstantEmitter(compiler, namer, makeConstantListTemplate);
 
+  js.Expression generateEmbeddedGlobalAccess(String global) {
+    // TODO(floitsch): We should not use "init" for globals.
+    return js.js("init.$global");
+  }
+
   void emitProgram(Program program) {
     List<Output> outputs = program.outputs;
     MainOutput mainUnit = outputs.first;
     js.Statement mainAst = emitMainUnit(program);
     String mainCode = js.prettyPrint(mainAst, compiler).getText();
     compiler.outputProvider(mainUnit.outputFileName, 'js')
         ..add(buildGeneratedBy(compiler))
         ..add(mainCode)
         ..close();
     compiler.assembledCode = mainCode;
@@ skipping 17 matching lines @@
     var suffix = '';
     if (compiler.hasBuildId) suffix = ' version: ${compiler.buildId}';
     return '// Generated by dart2js, the Dart to JavaScript compiler$suffix.\n';
   }
 
   js.Statement emitMainUnit(Program program) {
     MainOutput unit = program.outputs.first;
     List<js.Expression> elements = unit.libraries.map(emitLibrary).toList();
     elements.add(
         emitLazilyInitializedStatics(unit.staticLazilyInitializedFields));
+
+    js.Statement nativeBoilerplate;
+    if (NativeGenerator.needsBoilerplate(backend)) {
+      nativeBoilerplate = NativeGenerator.generateBoilerplate(
+          backend,
+          generateEmbeddedGlobalAccess,
+          // TODO(floitsch): convertToFastObject.
+          js.js("(function(x) { return x; })", []));
+    } else {
+      nativeBoilerplate = js.js.statement(";");
+    }
+
     js.Expression code = new js.ArrayInitializer(elements);
+
     return js.js.statement(
         boilerplate,

[sra1, 2015/01/05 20:14:23]

Use the uncached version unless you are sure that 'boilerplate' contains only
one of a finite number of strings.

[floitsch, 2015/01/06 12:54:57]

Boilerplate is a big string at the bottom of the file.
Am I missing something?

[sra1, 2015/01/07 04:43:28]

My bad.  I thought it was computed.
If it is a constant, give it a constant-like name.

[floitsch, 2015/01/07 13:11:46]

what's a constant-like name?
I wanted to use capitals but the editor is even warning me now...

         {'deferredInitializer': emitDeferredInitializerGlobal(program.loadMap),
          'holders': emitHolders(unit.holders),
          'cyclicThrow':
            backend.emitter.staticFunctionAccess(backend.getCyclicThrowHelper()),
          'outputContainsConstantList': program.outputContainsConstantList,
          'embeddedGlobals': emitEmbeddedGlobals(program.loadMap),
          'constants': emitConstants(unit.constants),
          'staticNonFinals': emitStaticNonFinalFields(unit.staticNonFinalFields),
+         'nativeBoilerplate': nativeBoilerplate,
          'eagerClasses': emitEagerClassInitializations(unit.libraries),
          'main': unit.main,
          'code': code});
   }
 
   js.Block emitHolders(List<Holder> holders) {
     // The top-level variables for holders must *not* be renamed by the
     // JavaScript pretty printer because a lot of code already uses the
     // non-renamed names. The generated code looks like this:
     //
@@ skipping 24 matching lines @@
 
   js.Block emitEmbeddedGlobals(Map<String, List<Output>> loadMap) {
     List<js.Property> globals = <js.Property>[];
 
     if (loadMap.isNotEmpty) {
       globals.addAll(emitLoadUrisAndHashes(loadMap));
       globals.add(emitIsHunkLoadedFunction());
       globals.add(emitInitializeLoadedHunk());
     }
 
-    if (globals.isEmpty) return new js.Block.empty();
-
     js.ObjectInitializer globalsObject = new js.ObjectInitializer(globals);
 
     List<js.Statement> statements =
         [new js.ExpressionStatement(
             new js.VariableDeclarationList(
                 [new js.VariableInitialization(
                     new js.VariableDeclaration("init", allowRename: false),
                     globalsObject)]))];
     return new js.Block(statements);
   }
@@ skipping 387 matching lines @@
 
   // Initialize globals.
   #embeddedGlobals;
 
   // Initialize constants.
   #constants;
 
   // Initialize static non-final fields.
   #staticNonFinals;
 
+  // Add native boilerplate code.
+  #nativeBoilerplate;
+
   // Initialize eager classes.
   #eagerClasses;
 
   var end = Date.now();
   print('Setup: ' + (end - start) + ' ms.');
 
   #main();  // Start main.
 
 }(Date.now(), #code)
 }""";
 
 }