--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/Compiler/src/com/sun/c1x/ir/Op2.java	Wed Apr 27 11:43:22 2011 +0200
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2009, 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.sun.c1x.ir;
+
+import com.sun.c1x.util.*;
+import com.sun.cri.bytecode.*;
+import com.sun.cri.ci.*;
+
+/**
+ * The {@code Op2} class is the base of arithmetic and logic operations with two inputs.
+ *
+ * @author Ben L. Titzer
+ */
+public abstract class Op2 extends Instruction {
+
+    /**
+     * The opcode of this instruction.
+     */
+    public final int opcode;
+
+    Value x;
+    Value y;
+
+    /**
+     * Creates a new Op2 instance.
+     * @param kind the result type of this instruction
+     * @param opcode the bytecode opcode
+     * @param x the first input instruction
+     * @param y the second input instruction
+     */
+    public Op2(CiKind kind, int opcode, Value x, Value y) {
+        super(kind);
+        this.opcode = opcode;
+        this.x = x;
+        this.y = y;
+    }
+
+    /**
+     * Gets the first input to this instruction.
+     * @return the first input to this instruction
+     */
+    public final Value x() {
+        return x;
+    }
+
+    /**
+     * Gets the second input to this instruction.
+     * @return the second input to this instruction
+     */
+    public final Value y() {
+        return y;
+    }
+
+    /**
+     * Swaps the operands of this instruction. This is only legal for commutative operations.
+     */
+    public void swapOperands() {
+        assert Bytecodes.isCommutative(opcode);
+        Value t = x;
+        x = y;
+        y = t;
+    }
+
+    /**
+     * Iterates over the inputs to this instruction.
+     * @param closure the closure to apply to each input value
+     */
+    @Override
+    public void inputValuesDo(ValueClosure closure) {
+        x = closure.apply(x);
+        y = closure.apply(y);
+    }
+
+    @Override
+    public int valueNumber() {
+        return Util.hash2(opcode, x, y);
+    }
+
+    @Override
+    public boolean valueEqual(Instruction i) {
+        if (i instanceof Op2) {
+            Op2 o = (Op2) i;
+            return opcode == o.opcode && x == o.x && y == o.y;
+        }
+        return false;
+    }
+}