sys/sys/assym.h

   1 /*-
   2  * Copyright (c) 1999 Marcel Moolenaar
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer
  10  *    in this position and unchanged.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. The name of the author may not be used to endorse or promote products
  15  *    derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * $FreeBSD: src/sys/sys/assym.h,v 1.3.2.1 2000/07/07 01:31:16 obrien Exp $
  29  * $DragonFly: src/sys/sys/assym.h,v 1.3 2004/12/30 07:01:52 cpressey Exp $
  30  */
  31
  32 #ifndef _SYS_ASSYM_H_
  33 #define _SYS_ASSYM_H_
  34
  35 #if !defined(_KERNEL) && !defined(_KERNEL_STRUCTURES)
  36 #error "This file should not be included by userland programs."
  37 #endif
  38
  39 /* Add an ASSYM_BIAS to all arrays to avoid zero-size, which can be
  40    mishandled in some compilers */
  41 #define ASSYM_BIAS              0x00100000
  42
  43 #define ASSYM_ABS(value)        ((value) < 0 ? -((value) + 1) + 1ULL : (value))
  44
  45 #define ASSYM(name, value)                                      \
  46 char name ## sign[((value) < 0 ? 1 : 0) + ASSYM_BIAS];                         \
  47 char name ## w0[(ASSYM_ABS(value) & 0xFFFFU) + ASSYM_BIAS];                    \
  48 char name ## w1[((ASSYM_ABS(value) & 0xFFFF0000UL) >> 16) + ASSYM_BIAS];       \
  49 char name ## w2[((ASSYM_ABS(value) & 0xFFFF00000000ULL) >> 32) + ASSYM_BIAS];  \
  50 char name ## w3[((ASSYM_ABS(value) & 0xFFFF000000000000ULL) >> 48) + ASSYM_BIAS]
  51
  52 #endif /* !_SYS_ASSYM_H_ */