dart2js: Initial implementation of inlining.

pkg/compiler/lib/src/js_backend/codegen/task.dart

Index: pkg/compiler/lib/src/js_backend/codegen/task.dart
diff --git a/pkg/compiler/lib/src/js_backend/codegen/task.dart b/pkg/compiler/lib/src/js_backend/codegen/task.dart
index 78f61cb1bad41b528b5bc101473c4eeb6b551b65..8a98f4ffd775fd51c656a6f5ec1af1c2fa5dc7e0 100644
--- a/pkg/compiler/lib/src/js_backend/codegen/task.dart
+++ b/pkg/compiler/lib/src/js_backend/codegen/task.dart
@@ -66,18 +66,22 @@ class CpsFunctionCompiler implements FunctionCompiler {
   final GenericTask treeBuilderTask;
   final GenericTask treeOptimizationTask;
 
+  Inliner inliner;
+
   CpsFunctionCompiler(Compiler compiler, JavaScriptBackend backend,
                       SourceInformationStrategy sourceInformationFactory)
       : fallbackCompiler =
             new ssa.SsaFunctionCompiler(backend, sourceInformationFactory),
         cpsBuilderTask = new IrBuilderTask(compiler, sourceInformationFactory),
-        this.sourceInformationFactory = sourceInformationFactory,
+        sourceInformationFactory = sourceInformationFactory,
         constantSystem = backend.constantSystem,
         compiler = compiler,
         glue = new Glue(compiler),
         cpsOptimizationTask = new GenericTask('CPS optimization', compiler),
         treeBuilderTask = new GenericTask('Tree builder', compiler),
-        treeOptimizationTask = new GenericTask('Tree optimization', compiler);
+      treeOptimizationTask = new GenericTask('Tree optimization', compiler) {
+    inliner = new Inliner(this);
+  }
 
   String get name => 'CPS Ir pipeline';
 
@@ -87,9 +91,9 @@ class CpsFunctionCompiler implements FunctionCompiler {
 
   /// Generates JavaScript code for `work.element`.
   js.Fun compile(CodegenWorkItem work) {
+    if (typeSystem == null) typeSystem = new TypeMaskSystem(compiler);
     AstElement element = work.element;
     return reporter.withCurrentElement(element, () {
-      typeSystem = new TypeMaskSystem(compiler);
       try {
         // TODO(karlklose): remove this fallback when we do not need it for
         // testing anymore.
@@ -102,7 +106,9 @@ class CpsFunctionCompiler implements FunctionCompiler {
           tracer.traceCompilation(element.name, null);
         }
         cps.FunctionDefinition cpsFunction = compileToCpsIr(element);
-        cpsFunction = optimizeCpsIr(cpsFunction);
+        optimizeCpsBeforeInlining(cpsFunction);
+        applyCpsPass(inliner, cpsFunction);
+        optimizeCpsAfterInlining(cpsFunction);
         cpsIntegrityChecker = null;
         tree_ir.FunctionDefinition treeFunction = compileToTreeIr(cpsFunction);
         treeFunction = optimizeTreeIr(treeFunction);
@@ -200,14 +206,19 @@ class CpsFunctionCompiler implements FunctionCompiler {
     return true; // So this can be used from assert().
   }
 
-  cps.FunctionDefinition optimizeCpsIr(cps.FunctionDefinition cpsFunction) {
+  void optimizeCpsBeforeInlining(cps.FunctionDefinition cpsFunction) {
     cpsOptimizationTask.measure(() {
       applyCpsPass(new RedundantJoinEliminator(), cpsFunction);
       applyCpsPass(new RedundantPhiEliminator(), cpsFunction);
       applyCpsPass(new InsertRefinements(typeSystem), cpsFunction);
-      applyCpsPass(new TypePropagator(compiler, typeSystem, this), cpsFunction);
+      applyCpsPass(new TypePropagator(this), cpsFunction);
       applyCpsPass(new RedundantJoinEliminator(), cpsFunction);
       applyCpsPass(new ShrinkingReducer(), cpsFunction);
+    });
+  }
+
+  void optimizeCpsAfterInlining(cps.FunctionDefinition cpsFunction) {
+    cpsOptimizationTask.measure(() {
       applyCpsPass(new RedundantRefinementEliminator(typeSystem), cpsFunction);
       applyCpsPass(new EagerlyLoadStatics(), cpsFunction);
       applyCpsPass(new GVN(compiler, typeSystem), cpsFunction);
@@ -222,7 +233,6 @@ class CpsFunctionCompiler implements FunctionCompiler {
       applyCpsPass(new OptimizeInterceptors(backend), cpsFunction);
       applyCpsPass(new ShrinkingReducer(), cpsFunction);
     });
-    return cpsFunction;
   }
 
   tree_ir.FunctionDefinition compileToTreeIr(cps.FunctionDefinition cpsNode) {