1 /* 2 * Copyright (c) 1998, 2007, 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 // For Sun Studio - implementation is in solaris_i486.il. 26 // For gcc - implementation is just below. 27 extern "C" u2 _raw_swap_u2(u2 x); 28 extern "C" u4 _raw_swap_u4(u4 x); 29 #ifdef AMD64 30 extern "C" u8 _raw_swap_u8(u8 x); 31 #else 32 extern "C" u8 _raw_swap_u8(u4 x, u4 y); 33 #endif // AMD64 34 35 // Efficient swapping of data bytes from Java byte 36 // ordering to native byte ordering and vice versa. 37 inline u2 Bytes::swap_u2(u2 x) { 38 return _raw_swap_u2(x); 39 } 40 41 inline u4 Bytes::swap_u4(u4 x) { 42 return _raw_swap_u4(x); 43 } 44 45 inline u8 Bytes::swap_u8(u8 x) { 46 #ifdef AMD64 47 return _raw_swap_u8(x); 48 #else 49 return swap_u8_base(*(u4*)&x, *(((u4*)&x)+1)); 50 #endif // AMD64 51 52 } 53 54 #ifndef AMD64 55 // Helper function for swap_u8 56 inline u8 Bytes::swap_u8_base(u4 x, u4 y) { 57 return _raw_swap_u8(x, y); 58 } 59 #endif // !AMD64 60 61 62 #ifdef _GNU_SOURCE 63 64 extern "C" { 65 #ifdef AMD64 66 inline u2 _raw_swap_u2(u2 x) { 67 register unsigned short int __dest; 68 __asm__ ("rorw $8, %w0": "=r" (__dest): "0" (x): "cc"); 69 return __dest; 70 } 71 inline u4 _raw_swap_u4(u4 x) { 72 register unsigned int __dest; 73 __asm__ ("bswap %0" : "=r" (__dest) : "0" (x)); 74 return __dest; 75 } 76 inline u8 _raw_swap_u8(u8 x) { 77 register unsigned long __dest; 78 __asm__ ("bswap %q0" : "=r" (__dest) : "0" (x)); 79 return __dest; 80 } 81 #else 82 inline u2 _raw_swap_u2(u2 x) { 83 u2 ret; 84 __asm__ __volatile__ ( 85 "movw %0, %%ax;" 86 "xchg %%al, %%ah;" 87 "movw %%ax, %0" 88 :"=r" (ret) // output : register 0 => ret 89 :"0" (x) // input : x => register 0 90 :"ax", "0" // clobbered registers 91 ); 92 return ret; 93 } 94 95 inline u4 _raw_swap_u4(u4 x) { 96 u4 ret; 97 __asm__ __volatile__ ( 98 "bswap %0" 99 :"=r" (ret) // output : register 0 => ret 100 :"0" (x) // input : x => register 0 101 :"0" // clobbered register 102 ); 103 return ret; 104 } 105 106 inline u8 _raw_swap_u8(u4 x, u4 y) { 107 return (((u8)_raw_swap_u4(x))<<32) | _raw_swap_u4(y); 108 } 109 #endif // AMD64 110 } 111 #endif //_GNU_SOURCE