# HG changeset patch
# User Doug Simon <doug.simon@oracle.com>
# Date 1367489981 -7200
# Node ID 9384ec90632be792e5b5526aad55711a5c6b1acd
# Parent  56dc7fe83f8a74c2fe4f12220e053ca98fc1134c# Parent  82b2a2c652bb7c8694e6cb1a4a97a61769e6676a
Merge.

diff -r 56dc7fe83f8a -r 9384ec90632b graal/com.oracle.graal.compiler.test/src/com/oracle/graal/compiler/test/EliminateNestedCheckCastsTest.java
--- a/graal/com.oracle.graal.compiler.test/src/com/oracle/graal/compiler/test/EliminateNestedCheckCastsTest.java	Thu May 02 11:40:07 2013 +0200
+++ b/graal/com.oracle.graal.compiler.test/src/com/oracle/graal/compiler/test/EliminateNestedCheckCastsTest.java	Thu May 02 12:19:41 2013 +0200
@@ -62,7 +62,33 @@
 
     @Test
     public void test2() {
-        compileSnippet("test2Snippet", 5, 2);
+        compileSnippet("test2Snippet", 5, 1);
+    }
+
+    public static long test3Snippet(A1 a1) {
+        long result = a1.x1;
+        A2 a2 = (A2) a1;
+        if (a1.x1 == 42) {
+            A3 a3 = (A3) a2;
+            result = a3.x3;
+        }
+        return result;
+    }
+
+    @Test
+    public void test3() {
+        compileSnippet("test3Snippet", 2, 2);
+    }
+
+    public static long test4Snippet(A1 a1, A1 b1) {
+        A2 a2 = (A2) a1;
+        A3 b3 = (A3) b1;
+        return a2.x2 + b3.x3;
+    }
+
+    @Test
+    public void test4() {
+        compileSnippet("test4Snippet", 2, 2);
     }
 
     private StructuredGraph compileSnippet(final String snippet, final int checkcasts, final int afterCanon) {
@@ -71,6 +97,7 @@
             @Override
             public StructuredGraph call() throws Exception {
                 StructuredGraph graph = parse(snippet);
+                Debug.dump(graph, "After parsing: " + snippet);
                 Assert.assertEquals(checkcasts, graph.getNodes().filter(CheckCastNode.class).count());
                 new CanonicalizerPhase.Instance(runtime(), new Assumptions(false)).apply(graph);
                 Assert.assertEquals(afterCanon, graph.getNodes(CheckCastNode.class).count());
diff -r 56dc7fe83f8a -r 9384ec90632b graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/java/CheckCastNode.java
--- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/java/CheckCastNode.java	Thu May 02 11:40:07 2013 +0200
+++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/java/CheckCastNode.java	Thu May 02 12:19:41 2013 +0200
@@ -85,10 +85,10 @@
             // checkcast.
             return object();
         }
-        // remove checkcast if the only usage is a more specific checkcast
-        if (usages().count() == 1) {
-            CheckCastNode ccn = usages().filter(CheckCastNode.class).first();
-            if (ccn != null && ccn.type() != null && type.isAssignableFrom(ccn.type())) {
+        // remove checkcast if next node is a more specific checkcast
+        if (next() instanceof CheckCastNode) {
+            CheckCastNode ccn = (CheckCastNode) next();
+            if (ccn != null && ccn.type() != null && this == ccn.object() && type.isAssignableFrom(ccn.type())) {
                 return object();
             }
         }