--- /dev/null	2018-06-17 23:18:20.806999507 +0800
+++ new/src/share/classes/jdk/jfr/internal/Bits.java	2019-01-29 10:59:23.742022470 +0800
@@ -0,0 +1,241 @@
+/*
+ * Copyright (c) 2016, 2019, 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 jdk.jfr.internal;
+
+import java.nio.ByteOrder;
+import java.security.AccessController;
+import sun.misc.Unsafe;
+
+final class Bits {                            // package-private
+
+    private static final Unsafe unsafe = Unsafe.getUnsafe();
+    private static final boolean unalignedAccess = unaligned();
+    private static final boolean bigEndian = (ByteOrder.nativeOrder() == ByteOrder.BIG_ENDIAN);
+
+    private Bits() { }
+
+    private static boolean unaligned;
+    private static boolean unalignedKnown = false;
+
+    private static boolean unaligned() {
+        if (unalignedKnown)
+            return unaligned;
+        String arch = AccessController.doPrivileged(
+            new sun.security.action.GetPropertyAction("os.arch"));
+        unaligned = arch.equals("i386") || arch.equals("x86")
+            || arch.equals("amd64") || arch.equals("x86_64")
+            || arch.equals("ppc64") || arch.equals("ppc64le");
+        unalignedKnown = true;
+        return unaligned;
+    }
+
+    // -- Swapping --
+
+    private static short swap(short x) {
+        return Short.reverseBytes(x);
+    }
+
+    private static char swap(char x) {
+        return Character.reverseBytes(x);
+    }
+
+    private static int swap(int x) {
+        return Integer.reverseBytes(x);
+    }
+
+    private static long swap(long x) {
+        return Long.reverseBytes(x);
+    }
+
+    private static float swap(float x) {
+        return Float.intBitsToFloat(swap(Float.floatToIntBits(x)));
+    }
+
+    private static double swap(double x) {
+        return Double.longBitsToDouble(swap(Double.doubleToLongBits(x)));
+    }
+
+    // -- Alignment --
+
+    private static boolean isAddressAligned(long a, int datumSize) {
+        return (a & datumSize - 1) == 0;
+    }
+
+    // -- Primitives stored per byte
+
+    private static byte char1(char x) { return (byte)(x >> 8); }
+    private static byte char0(char x) { return (byte)(x     ); }
+
+    private static byte short1(short x) { return (byte)(x >> 8); }
+    private static byte short0(short x) { return (byte)(x     ); }
+
+    private static byte int3(int x) { return (byte)(x >> 24); }
+    private static byte int2(int x) { return (byte)(x >> 16); }
+    private static byte int1(int x) { return (byte)(x >>  8); }
+    private static byte int0(int x) { return (byte)(x      ); }
+
+    private static byte long7(long x) { return (byte)(x >> 56); }
+    private static byte long6(long x) { return (byte)(x >> 48); }
+    private static byte long5(long x) { return (byte)(x >> 40); }
+    private static byte long4(long x) { return (byte)(x >> 32); }
+    private static byte long3(long x) { return (byte)(x >> 24); }
+    private static byte long2(long x) { return (byte)(x >> 16); }
+    private static byte long1(long x) { return (byte)(x >>  8); }
+    private static byte long0(long x) { return (byte)(x      ); }
+
+    private static void putCharBigEndianUnaligned(long a, char x) {
+        putByte_(a    , char1(x));
+        putByte_(a + 1, char0(x));
+    }
+
+    private static void putShortBigEndianUnaligned(long a, short x) {
+        putByte_(a    , short1(x));
+        putByte_(a + 1, short0(x));
+    }
+
+    private static void putIntBigEndianUnaligned(long a, int x) {
+        putByte_(a    , int3(x));
+        putByte_(a + 1, int2(x));
+        putByte_(a + 2, int1(x));
+        putByte_(a + 3, int0(x));
+    }
+
+    private static void putLongBigEndianUnaligned(long a, long x) {
+        putByte_(a    , long7(x));
+        putByte_(a + 1, long6(x));
+        putByte_(a + 2, long5(x));
+        putByte_(a + 3, long4(x));
+        putByte_(a + 4, long3(x));
+        putByte_(a + 5, long2(x));
+        putByte_(a + 6, long1(x));
+        putByte_(a + 7, long0(x));
+    }
+
+    private static void putFloatBigEndianUnaligned(long a, float x) {
+        putIntBigEndianUnaligned(a, Float.floatToRawIntBits(x));
+    }
+
+    private static void putDoubleBigEndianUnaligned(long a, double x) {
+        putLongBigEndianUnaligned(a, Double.doubleToRawLongBits(x));
+    }
+
+    private static void putByte_(long a, byte b) {
+        unsafe.putByte(a, b);
+    }
+
+    private static void putBoolean_(long a, boolean x) {
+        unsafe.putBoolean(null, a, x);
+    }
+
+    private static void putChar_(long a, char x) {
+        unsafe.putChar(a, bigEndian ? x : swap(x));
+    }
+
+    private static void putShort_(long a, short x) {
+        unsafe.putShort(a, bigEndian ? x : swap(x));
+    }
+
+    private static void putInt_(long a, int x) {
+        unsafe.putInt(a, bigEndian ? x : swap(x));
+    }
+
+    private static void putLong_(long a, long x) {
+        unsafe.putLong(a, bigEndian ? x : swap(x));
+    }
+
+    private static void putFloat_(long a, float x) {
+        unsafe.putFloat(a, bigEndian ? x : swap(x));
+    }
+
+    private static void putDouble_(long a, double x) {
+        unsafe.putDouble(a, bigEndian ? x : swap(x));
+    }
+
+    // external api
+    static int putByte(long a, byte x) {
+        putByte_(a, x);
+        return Byte.BYTES;
+    }
+
+    static int putBoolean(long a, boolean x) {
+        putBoolean_(a, x);
+        return Byte.BYTES;
+    }
+
+    static int putChar(long a, char x) {
+        if (unalignedAccess || isAddressAligned(a, Character.BYTES)) {
+            putChar_(a, x);
+            return Character.BYTES;
+        }
+        putCharBigEndianUnaligned(a, x);
+        return Character.BYTES;
+    }
+
+    static int putShort(long a, short x) {
+        if (unalignedAccess || isAddressAligned(a, Short.BYTES)) {
+            putShort_(a, x);
+            return Short.BYTES;
+        }
+        putShortBigEndianUnaligned(a, x);
+        return Short.BYTES;
+    }
+
+    static int putInt(long a, int x) {
+        if (unalignedAccess || isAddressAligned(a, Integer.BYTES)) {
+            putInt_(a, x);
+            return Integer.BYTES;
+        }
+        putIntBigEndianUnaligned(a, x);
+        return Integer.BYTES;
+    }
+
+    static int putLong(long a, long x) {
+         if (unalignedAccess || isAddressAligned(a, Long.BYTES)) {
+            putLong_(a, x);
+            return Long.BYTES;
+        }
+        putLongBigEndianUnaligned(a, x);
+        return Long.BYTES;
+    }
+
+    static int putFloat(long a, float x) {
+        if (unalignedAccess || isAddressAligned(a, Float.BYTES)) {
+            putFloat_(a, x);
+            return Float.BYTES;
+        }
+        putFloatBigEndianUnaligned(a, x);
+        return Float.BYTES;
+    }
+
+    static int putDouble(long a, double x) {
+        if (unalignedAccess || isAddressAligned(a, Double.BYTES)) {
+            putDouble_(a, x);
+            return Double.BYTES;
+        }
+        putDoubleBigEndianUnaligned(a, x);
+        return Double.BYTES;
+    }
+}