Add benchmark to measure performance of VH adapters

Reviewed-by: jvernee, psandoz

test/micro/org/openjdk/bench/jdk/incubator/foreign/TestAdaptVarHandles.java

@@ -0,0 +1,161 @@
+/*
+ * Copyright (c) 2020 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 org.openjdk.bench.jdk.incubator.foreign;
+
+import jdk.incubator.foreign.MemoryAddress;
+import jdk.incubator.foreign.MemoryHandles;
+import jdk.incubator.foreign.MemoryLayout;
+import jdk.incubator.foreign.MemoryLayouts;
+import jdk.incubator.foreign.MemorySegment;
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Fork;
+import org.openjdk.jmh.annotations.Measurement;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Setup;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.annotations.Warmup;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import java.lang.invoke.VarHandle;
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.AverageTime)
+@Warmup(iterations = 5, time = 500, timeUnit = TimeUnit.MILLISECONDS)
+@Measurement(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS)
+@State(org.openjdk.jmh.annotations.Scope.Thread)
+@OutputTimeUnit(TimeUnit.MILLISECONDS)
+@Fork(3)
+public class TestAdaptVarHandles {
+
+    static class IntBox {
+
+        private final int value;
+
+        IntBox(int value) {
+            this.value = value;
+        }
+
+        int intValue() {
+            return value;
+        }
+    }
+
+    static final int ELEM_SIZE = 1_000_000;
+
+    static final MethodHandle INT_TO_INTBOX;
+    static final MethodHandle INTBOX_TO_INT;
+
+    static {
+        try {
+            INT_TO_INTBOX = MethodHandles.lookup()
+                    .findConstructor(IntBox.class, MethodType.methodType(void.class, int.class));
+            INTBOX_TO_INT = MethodHandles.lookup()
+                    .findVirtual(IntBox.class, "intValue", MethodType.methodType(int.class));
+        } catch (Throwable ex) {
+            throw new ExceptionInInitializerError(ex);
+        }
+    }
+
+    static final VarHandle VH_int = MethodHandles.arrayElementVarHandle(int[].class);
+
+    static final VarHandle VH_box_int = MemoryHandles.filterValue(VH_int, INTBOX_TO_INT, INT_TO_INTBOX);
+
+    static final VarHandle VH_addr_int = MemoryLayout.ofSequence(MemoryLayouts.JAVA_INT)
+            .varHandle(int.class, MemoryLayout.PathElement.sequenceElement());
+
+    static final VarHandle VH_addr_box_int = MemoryHandles.filterValue(VH_addr_int, INTBOX_TO_INT, INT_TO_INTBOX);
+
+    static final MethodHandle MH_int = VH_int.toMethodHandle(VarHandle.AccessMode.GET);
+
+    static final MethodHandle MH_box_int = MethodHandles.filterReturnValue(MH_int, INT_TO_INTBOX);
+
+    int[] base = new int[ELEM_SIZE];
+    MemorySegment segment = MemorySegment.ofArray(base);
+
+    @Setup
+    public void setup() {
+        for (int i = 0; i < ELEM_SIZE; i++) {
+            base[i] = i;
+        }
+    }
+
+    @Benchmark
+    public int vh_loop() throws Throwable {
+        int sum = 0;
+        for (int i = 0; i < ELEM_SIZE; i++) {
+            sum += (int)VH_int.get(base, i);
+        }
+        return sum;
+    }
+
+    @Benchmark
+    public int vh_box_loop() throws Throwable {
+        int sum = 0;
+        for (int i = 0; i < ELEM_SIZE; i++) {
+            sum += ((IntBox)VH_box_int.get(base, i)).intValue();
+        }
+        return sum;
+    }
+
+    @Benchmark
+    public int mh_loop() throws Throwable {
+        int sum = 0;
+        for (int i = 0; i < ELEM_SIZE; i++) {
+            sum += (int)MH_int.invokeExact(base, i);
+        }
+        return sum;
+    }
+
+    @Benchmark
+    public int mh_box_loop() throws Throwable {
+        int sum = 0;
+        for (int i = 0; i < ELEM_SIZE; i++) {
+            sum += ((IntBox)MH_box_int.invokeExact(base, i)).intValue();
+        }
+        return sum;
+    }
+
+    @Benchmark
+    public int segment_loop() throws Throwable {
+        int sum = 0;
+        MemoryAddress baseAddress = segment.baseAddress();
+        for (int i = 0; i < ELEM_SIZE; i++) {
+            sum += (int)VH_addr_int.get(baseAddress, (long)i);
+        }
+        return sum;
+    }
+
+    @Benchmark
+    public int segment_box_loop() throws Throwable {
+        int sum = 0;
+        MemoryAddress baseAddress = segment.baseAddress();
+        for (int i = 0; i < ELEM_SIZE; i++) {
+            sum += ((IntBox)VH_addr_box_int.get(baseAddress, (long)i)).intValue();
+        }
+        return sum;
+    }
+}