bytes_linux_x86.inline.hpp revision 0:a61af66fc99e 
1/*
2 * Copyright 1999-2001 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25#include <byteswap.h>
26
27// Efficient swapping of data bytes from Java byte
28// ordering to native byte ordering and vice versa.
29inline u2   Bytes::swap_u2(u2 x) {
30#ifdef AMD64
31  return bswap_16(x);
32#else
33  u2 ret;
34  __asm__ __volatile__ (
35    "movw %0, %%ax;"
36    "xchg %%al, %%ah;"
37    "movw %%ax, %0"
38    :"=r" (ret)      // output : register 0 => ret
39    :"0"  (x)        // input  : x => register 0
40    :"ax", "0"       // clobbered registers
41  );
42  return ret;
43#endif // AMD64
44}
45
46inline u4   Bytes::swap_u4(u4 x) {
47#ifdef AMD64
48  return bswap_32(x);
49#else
50  u4 ret;
51  __asm__ __volatile__ (
52    "bswap %0"
53    :"=r" (ret)      // output : register 0 => ret
54    :"0"  (x)        // input  : x => register 0
55    :"0"             // clobbered register
56  );
57  return ret;
58#endif // AMD64
59}
60
61#ifdef AMD64
62inline u8 Bytes::swap_u8(u8 x) {
63  return bswap_64(x);
64}
65#else
66// Helper function for swap_u8
67inline u8   Bytes::swap_u8_base(u4 x, u4 y) {
68  return (((u8)swap_u4(x))<<32) | swap_u4(y);
69}
70
71inline u8 Bytes::swap_u8(u8 x) {
72  return swap_u8_base(*(u4*)&x, *(((u4*)&x)+1));
73}
74#endif // !AMD64
75