dart2js cps: Type casts and related changes to type propagation.

pkg/compiler/lib/src/tree_ir/tree_ir_builder.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 tree_ir_builder;
 
 import '../dart2jslib.dart' as dart2js;
 import '../dart_types.dart';
 import '../elements/elements.dart';
 import '../cps_ir/cps_ir_nodes.dart' as cps_ir;
@@ skipping 362 matching lines @@
 
   Statement visitThrow(cps_ir.Throw node) {
     Expression value = getVariableUse(node.value);
     return new Throw(value);
   }
 
   Statement visitRethrow(cps_ir.Rethrow node) {
     return new Rethrow();
   }
 
+  Statement visitUnreachable(cps_ir.Unreachable node) {
+    return new Unreachable();
+  }
+
   Expression visitNonTailThrow(cps_ir.NonTailThrow node) {
     unexpectedNode(node);
   }
 
   Statement continueWithExpression(cps_ir.Reference continuation,
                                    Expression expression) {
     cps_ir.Continuation cont = continuation.definition;
     if (cont == returnContinuation) {
       return new Return(expression);
     } else {
@@ skipping 15 matching lines @@
   Expression visitGetMutableVariable(cps_ir.GetMutableVariable node) {
     return getMutableVariableUse(node.variable);
   }
 
   Statement visitSetMutableVariable(cps_ir.SetMutableVariable node) {
     Variable variable = getMutableVariable(node.variable.definition);
     Expression value = getVariableUse(node.value);
     return Assign.makeStatement(variable, value, visit(node.body));
   }
 
-  Statement visitTypeOperator(cps_ir.TypeOperator node) {
+  Statement visitTypeCast(cps_ir.TypeCast node) {
     Expression value = getVariableUse(node.value);
     List<Expression> typeArgs = translateArguments(node.typeArguments);
-    Expression concat =
-        new TypeOperator(value, node.type, typeArgs,
-                         isTypeTest: node.isTypeTest);
-    return continueWithExpression(node.continuation, concat);
+    Expression expression =
+        new TypeOperator(value, node.type, typeArgs, isTypeTest: false);
+    return continueWithExpression(node.continuation, expression);
+  }
+
+  Expression visitTypeTest(cps_ir.TypeTest node) {
+    Expression value = getVariableUse(node.value);
+    List<Expression> typeArgs = translateArguments(node.typeArguments);
+    return new TypeOperator(value, node.type, typeArgs, isTypeTest: true);
   }
 
   Statement visitInvokeConstructor(cps_ir.InvokeConstructor node) {
     List<Expression> arguments = translateArguments(node.arguments);
     Expression invoke = new InvokeConstructor(
         node.type,
         node.target,
         node.selector,
         arguments);
     return continueWithExpression(node.continuation, invoke);
@@ skipping 137 matching lines @@
 
   Statement visitSetStatic(cps_ir.SetStatic node) {
     SetStatic setStatic = new SetStatic(
         node.element,
         getVariableUse(node.value),
         node.sourceInformation);
     return new ExpressionStatement(setStatic, visit(node.body));
   }
 }