| /* |
| * Copyright (c) 2016, 2018, 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 jdk.internal.misc.Unsafe; |
| |
| final class Bits { // package-private |
| |
| private static final Unsafe unsafe = Unsafe.getUnsafe(); |
| private static final boolean unalignedAccess = unsafe.unalignedAccess(); |
| private static final boolean bigEndian = unsafe.isBigEndian(); |
| |
| private Bits() { } |
| |
| // -- 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; |
| } |
| } |