Support break and labeled statements.

frog/leg/ssa/tracer.dart

 // Copyright (c) 2011, 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.
 
 class HTracer extends HGraphVisitor {
   int indent = 0;
   final StringBuffer output;
 
   factory HTracer.singleton() {
     if (_singleton === null) _singleton = new HTracer._internal();
@@ skipping 184 matching lines @@
   String visitBitOr(HBitOr node) => visitInvokeStatic(node);
 
   String visitBitXor(HBitXor node) => visitInvokeStatic(node);
 
   String visitBoundsCheck(HBoundsCheck node) {
     String lengthId = temporaryId(node.length);
     String indexId = temporaryId(node.index);
     return "Bounds check: length = $lengthId, index = $indexId";
   }
 
+  String visitBreak(HBreak node) {
+    if (node.label !== null) return "break " + node.label.stringValue;
+    return "break";
+  }
+
   String visitDivide(HDivide node) => visitInvokeStatic(node);
 
   String visitEquals(HEquals node) => visitInvokeStatic(node);
 
   String visitExit(HExit node) => "exit";
 
   String visitFieldGet(HFieldGet node) => 'get ${node.element.name}';
 
   String visitFieldSet(HFieldSet node) {
     String valueId = temporaryId(node.value);
@@ skipping 198 matching lines @@
       default: unreachable();
     }
     return "TypeGuard: ${temporaryId(node.inputs[0])} is $type";
   }
 
   String visitIs(HIs node) {
     String type = node.typeExpression.toString();
     return "TypeTest: ${temporaryId(node.expression)} is $type";
   }
 }