1 /* 2 * Copyright (c) 1999, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef OS_CPU_LINUX_X86_BYTES_LINUX_X86_INLINE_HPP 26 #define OS_CPU_LINUX_X86_BYTES_LINUX_X86_INLINE_HPP 27 28 #include <byteswap.h> 29 30 // Efficient swapping of data bytes from Java byte 31 // ordering to native byte ordering and vice versa. 32 inline u2 Bytes::swap_u2(u2 x) { 33 #ifdef AMD64 34 return bswap_16(x); 35 #else 36 u2 ret; 37 __asm__ __volatile__ ( 38 "movw %0, %%ax;" 39 "xchg %%al, %%ah;" 40 "movw %%ax, %0" 41 :"=r" (ret) // output : register 0 => ret 42 :"0" (x) // input : x => register 0 43 :"ax", "0" // clobbered registers 44 ); 45 return ret; 46 #endif // AMD64 47 } 48 49 inline u4 Bytes::swap_u4(u4 x) { 50 #ifdef AMD64 51 return bswap_32(x); 52 #else 53 u4 ret; 54 __asm__ __volatile__ ( 55 "bswap %0" 56 :"=r" (ret) // output : register 0 => ret 57 :"0" (x) // input : x => register 0 58 :"0" // clobbered register 59 ); 60 return ret; 61 #endif // AMD64 62 } 63 64 #ifdef AMD64 65 inline u8 Bytes::swap_u8(u8 x) { 66 return bswap_64(x); 67 } 68 #else 69 // Helper function for swap_u8 70 inline u8 Bytes::swap_u8_base(u4 x, u4 y) { 71 return (((u8)swap_u4(x))<<32) | swap_u4(y); 72 } 73 74 inline u8 Bytes::swap_u8(u8 x) { 75 return swap_u8_base(*(u4*)&x, *(((u4*)&x)+1)); 76 } 77 #endif // !AMD64 78 79 #endif // OS_CPU_LINUX_X86_BYTES_LINUX_X86_INLINE_HPP