--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/truffle/com.oracle.truffle.api.dsl.test/src/com/oracle/truffle/api/dsl/test/examples/MathPow.java	Wed Jun 17 10:58:08 2015 +0200
@@ -0,0 +1,143 @@
+/*
+ * Copyright (c) 2015, 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.truffle.api.dsl.test.examples;
+
+import static com.oracle.truffle.api.dsl.test.examples.ExampleNode.*;
+import static org.junit.Assert.*;
+
+import org.junit.*;
+
+import com.oracle.truffle.api.*;
+import com.oracle.truffle.api.dsl.*;
+import com.oracle.truffle.api.dsl.test.examples.MathPowFactory.MathPowNodeGen;
+import com.oracle.truffle.api.nodes.*;
+
+/**
+ * This example shows possible specializations for a simplified math pow node. It demonstrates how
+ * multiple caches can coexist within in the same node. This example does not show the best possible
+ * specializations for math.pow.
+ *
+ * Note: int values are implicitly casted to double values.
+ */
+@SuppressWarnings("unused")
+public class MathPow extends Node {
+
+    @Test
+    public void testPow() {
+        MathPowNode node = MathPowNodeGen.create(createArguments(2));
+        CallTarget target = createTarget(node);
+
+        // start with doPowCached
+        assertEquals(1D, target.call(1D, 1));
+        assertEquals(2D, target.call(2D, 1));
+        assertEquals(3D, target.call(3D, 1));
+        assertEquals(3, node.doPowCached);
+        assertEquals(0, node.doPowCachedExponent);
+
+        // transition to doPowCachedExponent
+        assertEquals(4D, target.call(4D, 1));
+        assertEquals(5D, target.call(5D, 1));
+        assertEquals(6D, target.call(6D, 1));
+        assertEquals(16D, target.call(4D, 2));
+        assertEquals(125D, target.call(5D, 3));
+        assertEquals(5, node.doPowCachedExponent);
+        assertEquals(0, node.doPowDoubleInt);
+
+        // transition to doPowDoubleInt
+        assertEquals(4D * 4D * 4D * 4D, target.call(4D, 4));
+        assertEquals(5D * 5D * 5D * 5D * 5D, target.call(5D, 5));
+        assertEquals(5, node.doPowCachedExponent);
+        assertEquals(2, node.doPowDoubleInt);
+
+        // transition to doPow
+        assertEquals(5D, target.call(5D, 1D));
+        assertEquals(2D, target.call(2D, 1D));
+
+        assertEquals(3, node.doPowCached);
+        assertEquals(5, node.doPowCachedExponent);
+        assertEquals(2, node.doPowDoubleInt);
+        assertEquals(2, node.doPow);
+    }
+
+    public static class MathPowNode extends ExampleNode {
+
+        // test flags
+        int doPowCached;
+        int doPowCachedExponent;
+        int doPowDoubleInt;
+        int doPow;
+
+        @Specialization(guards = {"base == cachedBase", "exponent == cachedExponent"})
+        double doPowCached(double base, int exponent, //
+                        @Cached("base") double cachedBase, //
+                        @Cached("exponent") int cachedExponent, //
+                        @Cached("cachePow(cachedBase, cachedExponent)") double cachedResult) {
+            doPowCached++;
+            return cachedResult;
+        }
+
+        /*
+         * We could just use the doPow specialization instead. But this makes the number of doPow
+         * calls more difficult to assert.
+         */
+        protected static double cachePow(double base, int exponent) {
+            return Math.pow(base, exponent);
+        }
+
+        @Specialization(contains = "doPowCached", guards = {"exponent == cachedExponent", "cachedExponent <= 10"})
+        double doPowCachedExponent(double base, int exponent, @Cached("exponent") int cachedExponent) {
+            doPowCachedExponent++;
+            double result = 1.0;
+            for (int i = 0; i < cachedExponent; i++) {
+                result *= base;
+            }
+            return result;
+        }
+
+        @Specialization(contains = "doPowCachedExponent", guards = "exponent >= 0")
+        double doPowDoubleInt(double base, int exponent) {
+            doPowDoubleInt++;
+            // Uses binary decomposition to limit the number of
+            // multiplications; see the discussion in "Hacker's Delight" by Henry
+            // S. Warren, Jr., figure 11-6, page 213.
+            double b = base;
+            int e = exponent;
+            double result = 1;
+            while (e > 0) {
+                if ((e & 1) == 1) {
+                    result *= b;
+                }
+                e >>= 1;
+                b *= b;
+            }
+            return result;
+        }
+
+        @Specialization(contains = {"doPowCached", "doPowDoubleInt"})
+        double doPow(double base, double exponent) {
+            doPow++;
+            return Math.pow(base, exponent);
+        }
+    }
+
+}