Support runtime check of function types.

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

Index: sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
diff --git a/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart b/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
index a050e26535ea9ecf23eaa525b3fb48ac56a2ee4b..71a3de97bebd0d29671776dcc0b04dc9a30d1e4e 100644
--- a/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
+++ b/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
@@ -2214,7 +2214,6 @@ abstract class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
     assert(invariant(input, !type.isMalformed,
                      message: 'Attempt to check malformed type $type'));
     Element element = type.element;
-
     if (element == backend.jsArrayClass) {
       checkArray(input, negative ? '!==': '===');
       return;
@@ -2518,6 +2517,7 @@ abstract class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
 
     assert(node.isCheckedModeCheck || node.isCastTypeCheck);
     DartType type = node.typeExpression;
+    assert(type.kind != TypeKind.TYPEDEF);
     if (type.kind == TypeKind.FUNCTION) {
       // TODO(5022): We currently generate $isFunction checks for
       // function types.
@@ -2526,53 +2526,17 @@ abstract class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
     }
     world.registerIsCheck(type, work.resolutionTree);
 
+    CheckedModeHelper helper;
     FunctionElement helperElement;
     if (node.isBooleanConversionCheck) {
-      helperElement =
-          compiler.findHelper(const SourceString('boolConversionCheck'));
+      helper =
+          const CheckedModeHelper(const SourceString('boolConversionCheck'));
     } else {
-      helperElement = backend.getCheckedModeHelper(type,
-          typeCast: node.isCastTypeCheck);
+      helper =
+          backend.getCheckedModeHelper(type, typeCast: node.isCastTypeCheck);
     }
-    world.registerStaticUse(helperElement);
-    List<js.Expression> arguments = <js.Expression>[];
-    use(node.checkedInput);
-    arguments.add(pop());
-    int parameterCount =
-        helperElement.computeSignature(compiler).parameterCount;
-    // TODO(johnniwinther): Refactor this to avoid using the parameter count
-    // to determine how the helper should be called.
-    if (node.typeExpression.kind == TypeKind.TYPE_VARIABLE) {
-      assert(parameterCount == 2);
-      use(node.typeRepresentation);
-      arguments.add(pop());
-    } else if (parameterCount == 2) {
-      // 2 arguments implies that the method is either [propertyTypeCheck],
-      // [propertyTypeCast] or [assertObjectIsSubtype].
-      assert(!type.isMalformed);
-      String additionalArgument = backend.namer.operatorIs(type.element);
-      arguments.add(js.string(additionalArgument));
-    } else if (parameterCount == 3) {
-      // 3 arguments implies that the method is [malformedTypeCheck].
-      assert(type.isMalformed);
-      String reasons = Types.fetchReasonsFromMalformedType(type);
-      arguments.add(js.string('$type'));
-      // TODO(johnniwinther): Handle escaping correctly.
-      arguments.add(js.string(reasons));
-    } else if (parameterCount == 4) {
-      Element element = type.element;
-      String isField = backend.namer.operatorIs(element);
-      arguments.add(js.string(isField));
-      use(node.typeRepresentation);
-      arguments.add(pop());
-      String asField = backend.namer.substitutionName(element);
-      arguments.add(js.string(asField));
-    } else {
-      assert(!type.isMalformed);
-      // No additional arguments needed.
-    }
-    String helperName = backend.namer.isolateAccess(helperElement);
-    push(new js.Call(new js.VariableUse(helperName), arguments));
+
+    push(helper.generateCall(this, node));
   }
 }