# HG changeset patch
# User Gilles Duboscq <duboscq@ssw.jku.at>
# Date 1333997010 -7200
# Node ID b64933dc4830c6ead7638025af6e5cb12203e852
# Parent  ae367987a18c7354cc7f0c9ddab9c4e4b4aed20f
Peeling loop depending on their entry probability

diff -r ae367987a18c -r b64933dc4830 graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/GraalOptions.java
--- a/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/GraalOptions.java	Mon Apr 09 20:30:41 2012 +0200
+++ b/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/GraalOptions.java	Mon Apr 09 20:43:30 2012 +0200
@@ -98,6 +98,9 @@
     //rematerialize settings
     public static float   MinimumUsageProbability            = 0.95f;
 
+    //loop transform settings
+    public static float   MinimumPeelProbability             = 0.25f;
+
     // debugging settings
     public static int     MethodEndBreakpointGuards          = 0;
     public static boolean ZapStackOnMethodEntry              = ____;
diff -r ae367987a18c -r b64933dc4830 graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/phases/LoopTransformPhase.java
--- a/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/phases/LoopTransformPhase.java	Mon Apr 09 20:30:41 2012 +0200
+++ b/graal/com.oracle.graal.compiler/src/com/oracle/graal/compiler/phases/LoopTransformPhase.java	Mon Apr 09 20:43:30 2012 +0200
@@ -24,6 +24,7 @@
 
 import java.util.*;
 
+import com.oracle.graal.compiler.*;
 import com.oracle.graal.compiler.loop.*;
 import com.oracle.graal.debug.*;
 import com.oracle.graal.lir.cfg.*;
@@ -44,8 +45,12 @@
                 }
             });
             for (Loop loop : loops) {
-                LoopTransformUtil.peel(loop);
-                Debug.dump(graph, "After peeling %s", loop);
+                double entryProbability = loop.loopBegin().forwardEnd().probability();
+                if (entryProbability > GraalOptions.MinimumPeelProbability) {
+                    Debug.log("Peeling %s", loop);
+                    LoopTransformUtil.peel(loop);
+                    Debug.dump(graph, "After peeling %s", loop);
+                }
             }
         }
     }