Fix break implementation.

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.
 
 #library('tracer');
 
 #import('dart:io');
 #import('ssa.dart');
 
 class HTracer extends HGraphVisitor {
@@ skipping 350 matching lines @@
 
   String visitMultiply(HMultiply node) => visitInvokeStatic(node);
 
   String visitNegate(HNegate node) => visitInvokeStatic(node);
 
   String visitNot(HNot node) => "Not: ${temporaryId(node.inputs[0])}";
 
   String visitParameterValue(HParameterValue node) => "p${node.element.name}";
 
   String visitPhi(HPhi phi) {
-    return "Phi(${temporaryId(phi.inputs[0])}, ${temporaryId(phi.inputs[1])})";
+    StringBuffer buffer = new StringBuffer();
+    buffer.add("Phi(");
+    for (int i = 0; i < phi.inputs.length; i++) {
+      if (i > 0) buffer.add(", ");
+      buffer.add(temporaryId(phi.inputs[i]));
+    }
+    buffer.add(")");
+    return buffer.toString();
   }
 
   String visitReturn(HReturn node) => "Return ${temporaryId(node.inputs[0])}";
 
   String visitShiftLeft(HShiftLeft node) => visitInvokeStatic(node);
 
   String visitShiftRight(HShiftRight node) => visitInvokeStatic(node);
 
   String visitStatic(HStatic node)
       => "Static ${node.element.name}";
@@ skipping 47 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";
   }
 }