8257837: Performance regression in heap byte buffer views

Reviewed-by: chegar, roland

Author: mcimadamore

src/hotspot/share/classfile/vmIntrinsics.hpp

@@ -495,6 +495,7 @@ class methodHandle;
   /* support for Unsafe */                                                                                              \
   do_class(jdk_internal_misc_Unsafe,               "jdk/internal/misc/Unsafe")                                          \
   do_class(sun_misc_Unsafe,                        "sun/misc/Unsafe")                                                   \
+  do_class(jdk_internal_misc_ScopedMemoryAccess,   "jdk/internal/misc/ScopedMemoryAccess")                              \
                                                                                                                         \
   do_intrinsic(_writeback0,               jdk_internal_misc_Unsafe,     writeback0_name, long_void_signature , F_RN)             \
    do_name(     writeback0_name,                                        "writeback0")                                            \

src/hotspot/share/oops/methodData.cpp

@@ -1586,7 +1586,8 @@ bool MethodData::profile_unsafe(const methodHandle& m, int bci) {
   Bytecode_invoke inv(m , bci);
   if (inv.is_invokevirtual()) {
     if (inv.klass() == vmSymbols::jdk_internal_misc_Unsafe() ||
-        inv.klass() == vmSymbols::sun_misc_Unsafe()) {
+        inv.klass() == vmSymbols::sun_misc_Unsafe() ||
+        inv.klass() == vmSymbols::jdk_internal_misc_ScopedMemoryAccess()) {
       ResourceMark rm;
       char* name = inv.name()->as_C_string();
       if (!strncmp(name, "get", 3) || !strncmp(name, "put", 3)) {

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

@@ -0,0 +1,118 @@
+/*
+ * 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 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.TearDown;
+import org.openjdk.jmh.annotations.Warmup;
+import sun.misc.Unsafe;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.FloatBuffer;
+import java.util.concurrent.TimeUnit;
+
+import static jdk.incubator.foreign.MemoryLayouts.JAVA_INT;
+
+@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(value = 3, jvmArgsAppend = { "--add-modules=jdk.incubator.foreign" })
+public class LoopOverPollutedBuffer {
+
+    static final int ELEM_SIZE = 1_000_000;
+    static final int CARRIER_SIZE = (int) JAVA_INT.byteSize();
+    static final int ALLOC_SIZE = ELEM_SIZE * CARRIER_SIZE;
+
+    static final Unsafe unsafe = Utils.unsafe;
+
+    ByteBuffer dbb = ByteBuffer.allocateDirect(ALLOC_SIZE).order(ByteOrder.nativeOrder());
+    byte[] arr = new byte[ALLOC_SIZE];
+    ByteBuffer hbb = ByteBuffer.wrap(arr).order(ByteOrder.nativeOrder());
+    FloatBuffer hfb = hbb.asFloatBuffer();
+
+
+    @Setup
+    public void setup() {
+        for (int i = 0; i < ELEM_SIZE; i++) {
+            dbb.putFloat(i * 4, i);
+            hbb.putFloat(i * 4, i);
+        }
+        for (int i = 0; i < ELEM_SIZE; i++) {
+            hfb.put(i, i);
+        }
+    }
+
+    @TearDown
+    public void tearDown() {
+        unsafe.invokeCleaner(dbb);
+        arr = null;
+        hbb = null;
+        hfb = null;
+    }
+
+    @Benchmark
+    public int direct_byte_buffer_get_float() {
+        int sum = 0;
+        for (int k = 0; k < ELEM_SIZE; k++) {
+            dbb.putFloat(k, (float)k + 1);
+            float v = dbb.getFloat(k * 4);
+            sum += (int)v;
+        }
+        return sum;
+    }
+
+    @Benchmark
+    public int heap_byte_buffer_get_int() {
+        int sum = 0;
+        for (int k = 0; k < ELEM_SIZE; k++) {
+            hbb.putInt(k, k + 1);
+            int v = hbb.getInt(k * 4);
+            sum += v;
+        }
+        return sum;
+    }
+
+    @Benchmark
+    public int unsafe_get_float() {
+        int sum = 0;
+        for (int k = 0; k < ALLOC_SIZE; k += 4) {
+            unsafe.putFloat(arr, k + Unsafe.ARRAY_BYTE_BASE_OFFSET, k + 1);
+            float v = unsafe.getFloat(arr, k + Unsafe.ARRAY_BYTE_BASE_OFFSET);
+            sum += (int)v;
+        }
+        return sum;
+    }
+}