1 /* $NetBSD: byte_swap.h,v 1.2 2005/12/24 20:06:47 perry Exp $ */ 2 3 /*- 4 * Copyright (c) 1998 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Charles M. Hannum. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 /* 40 * Copy of the i386 version. 64 bit versions may be added later. 41 */ 42 43 #ifndef _AMD64_BYTE_SWAP_H_ 44 #define _AMD64_BYTE_SWAP_H_ 45 46 #include <sys/types.h> 47 48 static inline u_int32_t __byte_swap_long_variable(u_int32_t); 49 static inline u_int16_t __byte_swap_word_variable(u_int16_t); 50 51 static inline u_int32_t 52 __byte_swap_long_variable(u_int32_t x) 53 { 54 __asm volatile ( "bswap %1" : "=r" (x) : "0" (x)); 55 return (x); 56 } 57 58 static inline u_int16_t 59 __byte_swap_word_variable(u_int16_t x) 60 { 61 __asm volatile ("rorw $8, %w1" : "=r" (x) : "0" (x)); 62 return (x); 63 } 64 65 66 #ifdef __OPTIMIZE__ 67 68 #define __byte_swap_long_constant(x) \ 69 ((((x) & 0xff000000) >> 24) | \ 70 (((x) & 0x00ff0000) >> 8) | \ 71 (((x) & 0x0000ff00) << 8) | \ 72 (((x) & 0x000000ff) << 24)) 73 #define __byte_swap_word_constant(x) \ 74 ((((x) & 0xff00) >> 8) | \ 75 (((x) & 0x00ff) << 8)) 76 #define __byte_swap_long(x) \ 77 (__builtin_constant_p((x)) ? \ 78 __byte_swap_long_constant(x) : __byte_swap_long_variable(x)) 79 #define __byte_swap_word(x) \ 80 (__builtin_constant_p((x)) ? \ 81 __byte_swap_word_constant(x) : __byte_swap_word_variable(x)) 82 83 #else /* __OPTIMIZE__ */ 84 85 #define __byte_swap_long(x) __byte_swap_long_variable(x) 86 #define __byte_swap_word(x) __byte_swap_word_variable(x) 87 88 #endif /* __OPTIMIZE__ */ 89 90 #endif /* !_AMD64_BYTE_SWAP_H_ */ 91