# HG changeset patch
# User Thomas Wuerthinger <thomas.wuerthinger@oracle.com>
# Date 1433280046 -7200
# Node ID 5731adc3a10aa731ef1f8723fb6c1475149885c9
# Parent  942793d2a513ae8c66ca02eba99c7213112ada42
Eliminate fixed boxing node if it has no usages.

diff -r 942793d2a513 -r 5731adc3a10a graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/extended/BoxNode.java
--- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/extended/BoxNode.java	Tue Jun 02 21:07:25 2015 +0200
+++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/extended/BoxNode.java	Tue Jun 02 23:20:46 2015 +0200
@@ -26,6 +26,7 @@
 
 import com.oracle.graal.compiler.common.type.*;
 import com.oracle.graal.graph.*;
+import com.oracle.graal.graph.spi.*;
 import com.oracle.graal.nodeinfo.*;
 import com.oracle.graal.nodes.*;
 import com.oracle.graal.nodes.java.*;
@@ -39,7 +40,7 @@
  * methods in Integer, Long, etc.
  */
 @NodeInfo
-public final class BoxNode extends FixedWithNextNode implements VirtualizableAllocation, Lowerable {
+public final class BoxNode extends FixedWithNextNode implements VirtualizableAllocation, Lowerable, Canonicalizable.Unary<ValueNode> {
 
     public static final NodeClass<BoxNode> TYPE = NodeClass.create(BoxNode.class);
     @Input private ValueNode value;
@@ -65,6 +66,14 @@
     }
 
     @Override
+    public ValueNode canonical(CanonicalizerTool tool, ValueNode forValue) {
+        if (tool.allUsagesAvailable() && hasNoUsages()) {
+            return null;
+        }
+        return this;
+    }
+
+    @Override
     public void virtualize(VirtualizerTool tool) {
         ValueNode v = tool.getReplacedValue(getValue());
         ResolvedJavaType type = StampTool.typeOrNull(stamp());