# HG changeset patch
# User Lukas Stadler <lukas.stadler@oracle.com>
# Date 1397727134 -7200
# Node ID 530c56922a593d53fe7491db2c89b37d12d097dd
# Parent  c570c2fe9d2b65a446b414880d47f933ce1a6c01
push similar nodes through IfNodes

diff -r c570c2fe9d2b -r 530c56922a59 graal/com.oracle.graal.compiler.test/src/com/oracle/graal/compiler/test/PushThroughIfTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.graal.compiler.test/src/com/oracle/graal/compiler/test/PushThroughIfTest.java	Thu Apr 17 11:32:14 2014 +0200
@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.graal.compiler.test;
+
+import org.junit.*;
+
+import com.oracle.graal.api.code.*;
+import com.oracle.graal.debug.*;
+import com.oracle.graal.nodes.*;
+import com.oracle.graal.nodes.util.*;
+import com.oracle.graal.phases.common.*;
+import com.oracle.graal.phases.tiers.*;
+
+public class PushThroughIfTest extends GraalCompilerTest {
+
+    public int field1;
+    public int field2;
+
+    public int testSnippet(boolean b) {
+        int i;
+        if (b) {
+            i = field1;
+        } else {
+            i = field1;
+        }
+        return i + field2;
+    }
+
+    @SuppressWarnings("unused")
+    public int referenceSnippet(boolean b) {
+        return field1 + field2;
+    }
+
+    @Test
+    public void test1() {
+        test("testSnippet", "referenceSnippet");
+    }
+
+    private void test(String snippet, String reference) {
+        StructuredGraph graph = parse(snippet);
+        Debug.dump(graph, "Graph");
+        for (FrameState fs : graph.getNodes(FrameState.class).snapshot()) {
+            fs.replaceAtUsages(null);
+            GraphUtil.killWithUnusedFloatingInputs(fs);
+        }
+        new CanonicalizerPhase(true).apply(graph, new PhaseContext(getProviders(), new Assumptions(false)));
+        new CanonicalizerPhase(true).apply(graph, new PhaseContext(getProviders(), new Assumptions(false)));
+
+        StructuredGraph referenceGraph = parse(reference);
+        for (FrameState fs : referenceGraph.getNodes(FrameState.class).snapshot()) {
+            fs.replaceAtUsages(null);
+            GraphUtil.killWithUnusedFloatingInputs(fs);
+        }
+        new CanonicalizerPhase(true).apply(referenceGraph, new PhaseContext(getProviders(), new Assumptions(false)));
+        assertEquals(referenceGraph, graph);
+    }
+}
diff -r c570c2fe9d2b -r 530c56922a59 graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/IfNode.java
--- a/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/IfNode.java	Thu Apr 17 10:26:13 2014 +0200
+++ b/graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/IfNode.java	Thu Apr 17 11:32:14 2014 +0200
@@ -158,6 +158,41 @@
             this.safeDelete();
             return;
         }
+        if (trueSuccessor().usages().isEmpty() && falseSuccessor().usages().isEmpty()) {
+            // push similar nodes upwards through the if, thereby deduplicating them
+            do {
+                BeginNode trueSucc = trueSuccessor();
+                BeginNode falseSucc = falseSuccessor();
+                if (trueSucc.getClass() == BeginNode.class && falseSucc.getClass() == BeginNode.class && trueSucc.next() instanceof FixedWithNextNode && falseSucc.next() instanceof FixedWithNextNode) {
+                    FixedWithNextNode trueNext = (FixedWithNextNode) trueSucc.next();
+                    FixedWithNextNode falseNext = (FixedWithNextNode) falseSucc.next();
+                    NodeClass nodeClass = trueNext.getNodeClass();
+                    if (trueNext.getClass() == falseNext.getClass()) {
+                        if (nodeClass.inputsEqual(trueNext, falseNext) && nodeClass.valueEqual(trueNext, falseNext)) {
+                            falseNext.replaceAtUsages(trueNext);
+                            graph().removeFixed(falseNext);
+                            FixedNode next = trueNext.next();
+                            trueNext.setNext(null);
+                            trueNext.replaceAtPredecessor(next);
+                            graph().addBeforeFixed(this, trueNext);
+                            for (Node usage : trueNext.usages().snapshot()) {
+                                if (usage.getNodeClass().valueNumberable() && !usage.getNodeClass().isLeafNode()) {
+                                    Node newNode = graph().findDuplicate(usage);
+                                    if (newNode != null) {
+                                        usage.replaceAtUsages(newNode);
+                                        usage.safeDelete();
+                                    }
+                                }
+                                if (usage.isAlive()) {
+                                    tool.addToWorkList(usage);
+                                }
+                            }
+                            continue;
+                        }
+                    }
+                }
+            } while (false);
+        }
 
         if (condition() instanceof LogicConstantNode) {
             LogicConstantNode c = (LogicConstantNode) condition();