# HG changeset patch
# User Bernhard Urban <bernhard.urban@jku.at>
# Date 1380178255 -7200
# Node ID 60f6d59399415622405a3c958a4097579c9ebe99
# Parent  eb2def6529bc0f35bf7d7b4d405789560ab6f83b
LoweringPhase: add comment

diff -r eb2def6529bc -r 60f6d5939941 graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/LoweringPhase.java
--- a/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/LoweringPhase.java	Wed Sep 25 17:07:33 2013 +0200
+++ b/graal/com.oracle.graal.phases.common/src/com/oracle/graal/phases/common/LoweringPhase.java	Thu Sep 26 08:50:55 2013 +0200
@@ -278,6 +278,10 @@
                     Node nextLastFixed = nextNode.predecessor();
                     if (!(nextLastFixed instanceof FixedWithNextNode)) {
                         // insert begin node, to have a valid last fixed for next lowerable node.
+                        // This is about lowering a FixedWithNextNode to a control split while this
+                        // FixedWithNextNode is followed by some kind of BeginNode.
+                        // For example the when a FixedGuard followed by a loop exit is lowered to a
+                        // control-split + deopt.
                         BeginNode begin = node.graph().add(new BeginNode());
                         nextLastFixed.replaceFirstSuccessor(nextNode, begin);
                         begin.setNext(nextNode);