# HG changeset patch
# User Thomas Wuerthinger <thomas.wuerthinger@oracle.com>
# Date 1425897189 -3600
# Node ID 95d0385ec788340ef5ec26862b914b9711754da2
# Parent  055a095424a7ed6844ca34c024ed26fe7191c20f
Correctly handle corner case in AbstractBeginNode#removeProxies.

diff -r 055a095424a7 -r 95d0385ec788 graal/com.oracle.graal.graph/src/com/oracle/graal/graph/Node.java
--- a/graal/com.oracle.graal.graph/src/com/oracle/graal/graph/Node.java	Mon Mar 09 01:24:00 2015 +0100
+++ b/graal/com.oracle.graal.graph/src/com/oracle/graal/graph/Node.java	Mon Mar 09 11:33:09 2015 +0100
@@ -345,6 +345,13 @@
         return this.usage0 == null;
     }
 
+    /**
+     * Checks whether this node has usages.
+     */
+    public final boolean hasUsages() {
+        return this.usage0 != null;
+    }
+
     void reverseUsageOrder() {
         List<Node> snapshot = this.usages().snapshot();
         for (Node n : snapshot) {
diff -r 055a095424a7 -r 95d0385ec788 graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/AbstractBeginNode.java
--- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/AbstractBeginNode.java	Mon Mar 09 01:24:00 2015 +0100
+++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/AbstractBeginNode.java	Mon Mar 09 11:33:09 2015 +0100
@@ -94,10 +94,19 @@
     }
 
     public void removeProxies() {
-        for (ProxyNode vpn : proxies().snapshot()) {
-            // can not use graph.replaceFloating because vpn.value may be null during killCFG
-            vpn.replaceAtUsages(vpn.value());
-            vpn.safeDelete();
+        if (this.hasUsages()) {
+            outer: while (true) {
+                for (ProxyNode vpn : proxies().snapshot()) {
+                    ValueNode value = vpn.value();
+                    vpn.replaceAtUsages(value);
+                    vpn.safeDelete();
+                    if (value == this) {
+                        // Guard proxy could have this input as value.
+                        continue outer;
+                    }
+                }
+                break;
+            }
         }
     }