--- a/graal/GraalCompiler/src/com/sun/c1x/ir/BlockEnd.java	Fri May 20 14:09:28 2011 +0200
+++ b/graal/GraalCompiler/src/com/sun/c1x/ir/BlockEnd.java	Fri May 20 14:22:19 2011 +0200
@@ -77,8 +77,9 @@
         return (BlockBegin) successors().get(super.successorCount() + SUCCESSOR_COUNT + index);
     }
 
-    public BlockBegin setBlockSuccessor(int index, BlockBegin n) {
+    public Instruction setBlockSuccessor(int index, Instruction n) {
         assert index >= 0 && index < blockSuccessorCount;
+        assert n instanceof BlockBegin : "only BlockBegins, for now...";
         return (BlockBegin) successors().set(super.successorCount() + SUCCESSOR_COUNT + index, n);
     }
 
@@ -93,7 +94,7 @@
      * @param isSafepoint {@code true} if this instruction is a safepoint instruction
      * @param successors the list of successor blocks. If {@code null}, a new one will be created.
      */
-    public BlockEnd(CiKind kind, FrameState stateAfter, List<BlockBegin> blockSuccessors, int inputCount, int successorCount, Graph graph) {
+    public BlockEnd(CiKind kind, FrameState stateAfter, List<? extends Instruction> blockSuccessors, int inputCount, int successorCount, Graph graph) {
         this(kind, stateAfter, blockSuccessors.size(), inputCount, successorCount, graph);
         for (int i = 0; i < blockSuccessors.size(); i++) {
             setBlockSuccessor(i, blockSuccessors.get(i));
@@ -166,7 +167,7 @@
      */
     public void reorderSuccessor(int i, int backEdgeIndex) {
         assert i >= 0 && i < blockSuccessorCount;
-        BlockBegin successor = blockSuccessor(i);
+        Instruction successor = blockSuccessor(i);
         if (successor != null) {
             successors().set(super.successorCount() + SUCCESSOR_COUNT + i, Node.Null);
             successors().set(super.successorCount() + SUCCESSOR_COUNT + i, successor, backEdgeIndex);