include/arch/i386/include/byte_swap.h

   1 /*      $NetBSD: byte_swap.h,v 1.15 2008/04/28 20:23:24 martin 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  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #ifndef _I386_BYTE_SWAP_H_
  33 #define _I386_BYTE_SWAP_H_
  34
  35 #include <sys/types.h>
  36
  37 #ifdef  __GNUC__
  38 __BEGIN_DECLS
  39
  40 #define __BYTE_SWAP_U32_VARIABLE __byte_swap_u32_variable
  41 static __inline uint32_t __byte_swap_u32_variable(uint32_t);
  42 static __inline uint32_t
  43 __byte_swap_u32_variable(uint32_t x)
  44 {
  45         __asm volatile (
  46             "bswap %1"
  47             : "=r" (x) : "0" (x));
  48         return (x);
  49 }
  50
  51 #define __BYTE_SWAP_U16_VARIABLE __byte_swap_u16_variable
  52 static __inline uint16_t __byte_swap_u16_variable(uint16_t);
  53 static __inline uint16_t
  54 __byte_swap_u16_variable(uint16_t x)
  55 {
  56         __asm volatile ("rorw $8, %w1" : "=r" (x) : "0" (x));
  57         return (x);
  58 }
  59
  60 __END_DECLS
  61 #elif defined(_KERNEL) || defined(_LKM)
  62 #define __BYTE_SWAP_U32_VARIABLE __byte_swap_u32_variable
  63 #define __BYTE_SWAP_U16_VARIABLE __byte_swap_u16_variable
  64 uint32_t        __byte_swap_u32_variable(uint32_t);
  65 uint16_t        __byte_swap_u16_variable(uint16_t);
  66 #endif
  67
  68 #endif /* !_I386_BYTE_SWAP_H_ */