Support runtime check of function types.

sdk/lib/_internal/compiler/implementation/ssa/builder.dart

Index: sdk/lib/_internal/compiler/implementation/ssa/builder.dart
diff --git a/sdk/lib/_internal/compiler/implementation/ssa/builder.dart b/sdk/lib/_internal/compiler/implementation/ssa/builder.dart
index 37e3b148248397ebd0b30e7fa551511e12bea678..cc3b312f01ccdd27e38cd8b857a18adb88c15326 100644
--- a/sdk/lib/_internal/compiler/implementation/ssa/builder.dart
+++ b/sdk/lib/_internal/compiler/implementation/ssa/builder.dart
@@ -1627,8 +1627,10 @@ class SsaBuilder extends ResolvedVisitor implements Visitor {
       HInstruction original, DartType type,
       { int kind: HTypeConversion.CHECKED_MODE_CHECK }) {
     if (!compiler.enableTypeAssertions) return original;
+    type = type.unalias(compiler);
     HInstruction other = original.convertType(compiler, type, kind);
     if (other != original) add(other);
+    compiler.enqueuer.codegen.registerIsCheck(type, work.resolutionTree);
     return other;
   }
 
@@ -2231,6 +2233,12 @@ class SsaBuilder extends ResolvedVisitor implements Visitor {
         compiler.functionClass.computeType(compiler),
         compiler);
     push(new HForeignNew(closureClassElement, type, capturedVariables));
+
+    Element methodElement = nestedClosureData.closureElement;
+    if (compiler.backend.methodNeedsRti(methodElement)) {
+      compiler.backend.registerGenericClosure(
+          methodElement, compiler.enqueuer.codegen, work.resolutionTree);
+    }
   }
 
   visitFunctionDeclaration(FunctionDeclaration node) {
@@ -2609,7 +2617,7 @@ class SsaBuilder extends ResolvedVisitor implements Visitor {
     }
   }
 
-  visitOperatorSend(node) {
+  visitOperatorSend(Send node) {
     Operator op = node.selector;
     if (const SourceString("[]") == op.source) {
       visitDynamicSend(node);
@@ -2654,6 +2662,7 @@ class SsaBuilder extends ResolvedVisitor implements Visitor {
       isNot = true;
     }
     DartType type = elements.getType(typeAnnotation);
+    type = type.unalias(compiler);
     if (type.isMalformed) {
       String reasons = Types.fetchReasonsFromMalformedType(type);
       if (compiler.enableTypeAssertions) {
@@ -2665,7 +2674,39 @@ class SsaBuilder extends ResolvedVisitor implements Visitor {
     }
 
     HInstruction instruction;
-    if (type.kind == TypeKind.TYPE_VARIABLE) {
+    if (type.kind == TypeKind.FUNCTION) {
+      Element checkFunctionSubtype = backend.getCheckFunctionSubtype();
+      HInstruction isFuncSubtypeCall = new HStatic(checkFunctionSubtype);
+      add(isFuncSubtypeCall);
+
+      HInstruction signatureName = graph.addConstantString(
+          new DartString.literal(backend.namer.getFunctionTypeName(type)),
+          node, constantSystem);
+
+      HInstruction context;
+      HInstruction contextName;
+      if (type.containsTypeVariables) {
+        context = localsHandler.readThis();
+
+        ClassElement contextClass = Types.getClassContext(type);
+        contextName = graph.addConstantString(
+            new DartString.literal(backend.namer.getName(contextClass)),
+            node, constantSystem);
+      } else {
+        context = graph.addConstantNull(constantSystem);
+        contextName = graph.addConstantNull(constantSystem);
+      }
+
+      List<HInstruction> inputs = <HInstruction>[isFuncSubtypeCall,
+                                                 expression,
+                                                 signatureName,
+                                                 context,
+                                                 contextName];
+      HInstruction call = new HInvokeStatic(inputs, HType.UNKNOWN);
+      add(call);
+      instruction = new HIs(type, <HInstruction>[expression, call],
+          HIs.COMPOUND_CHECK);
+    } else if (type.kind == TypeKind.TYPE_VARIABLE) {
       HInstruction runtimeType = addTypeVariableReference(type);
       Element helper = backend.getGetObjectIsSubtype();
       HInstruction helperCall = new HStatic(helper);
@@ -3041,6 +3082,28 @@ class SsaBuilder extends ResolvedVisitor implements Visitor {
       stack.add(addConstantString(node, backend.namer.operatorIsPrefix()));
     } else if (name == const SourceString('JS_OPERATOR_AS_PREFIX')) {
       stack.add(addConstantString(node, backend.namer.operatorAsPrefix()));
+    } else if (name == const SourceString('JS_SIGNATURE_NAME')) {
+      stack.add(addConstantString(node, backend.namer.operatorSignature()));
+    } else if (name == const SourceString('JS_FUNCTION_TYPE_TAG')) {
+      stack.add(addConstantString(node, backend.namer.functionTypeTag()));
+    } else if (name == const SourceString('JS_FUNCTION_TYPE_VOID_RETURN_TAG')) {
+      stack.add(addConstantString(node,
+                                  backend.namer.functionTypeVoidReturnTag()));
+    } else if (name == const SourceString('JS_FUNCTION_TYPE_RETURN_TYPE_TAG')) {
+      stack.add(addConstantString(node,
+                                  backend.namer.functionTypeReturnTypeTag()));
+    } else if (name ==
+               const SourceString('JS_FUNCTION_TYPE_REQUIRED_PARAMETERS_TAG')) {
+      stack.add(addConstantString(node,
+          backend.namer.functionTypeRequiredParametersTag()));
+    } else if (name ==
+               const SourceString('JS_FUNCTION_TYPE_OPTIONAL_PARAMETERS_TAG')) {
+      stack.add(addConstantString(node,
+          backend.namer.functionTypeOptionalParametersTag()));
+    } else if (name ==
+               const SourceString('JS_FUNCTION_TYPE_NAMED_PARAMETERS_TAG')) {
+      stack.add(addConstantString(node,
+          backend.namer.functionTypeNamedParametersTag()));
     } else if (name == const SourceString('JS_DART_OBJECT_CONSTRUCTOR')) {
       handleForeignDartObjectJsConstructorFunction(node);
     } else {