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minix/sys/sys/bitops.h
Lionel Sambuc 84d9c625bf Synchronize on NetBSD-CVS (2013/12/1 12:00:00 UTC) 
- Fix for possible unset uid/gid in toproto
 - Fix for default mtree style
 - Update libelf
 - Importing libexecinfo
 - Resynchronize GCC, mpc, gmp, mpfr
 - build.sh: Replace params with show-params.
     This has been done as the make target has been renamed in the same
     way, while a new target named params has been added. This new
     target generates a file containing all the parameters, instead of
     printing it on the console.
 - Update test48 with new etc/services (Fix by Ben Gras <ben@minix3.org)
     get getservbyport() out of the inner loop

Change-Id: Ie6ad5226fa2621ff9f0dee8782ea48f9443d2091
2014-07-28 17:05:06 +02:00

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/* $NetBSD: bitops.h,v 1.11 2012/12/07 02:27:58 christos Exp $ */
/*-
* Copyright (c) 2007, 2010 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas and Joerg Sonnenberger.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _SYS_BITOPS_H_
#define _SYS_BITOPS_H_
#include <sys/stdint.h>
/*
* Find First Set functions
*/
#ifndef ffs32
static __inline int __unused
ffs32(uint32_t _n)
{
int _v;
if (!_n)
return 0;
_v = 1;
if ((_n & 0x0000FFFFU) == 0) {
_n >>= 16;
_v += 16;
}
if ((_n & 0x000000FFU) == 0) {
_n >>= 8;
_v += 8;
}
if ((_n & 0x0000000FU) == 0) {
_n >>= 4;
_v += 4;
}
if ((_n & 0x00000003U) == 0) {
_n >>= 2;
_v += 2;
}
if ((_n & 0x00000001U) == 0) {
_n >>= 1;
_v += 1;
}
return _v;
}
#endif
#ifndef ffs64
static __inline int __unused
ffs64(uint64_t _n)
{
int _v;
if (!_n)
return 0;
_v = 1;
if ((_n & 0x00000000FFFFFFFFULL) == 0) {
_n >>= 32;
_v += 32;
}
if ((_n & 0x000000000000FFFFULL) == 0) {
_n >>= 16;
_v += 16;
}
if ((_n & 0x00000000000000FFULL) == 0) {
_n >>= 8;
_v += 8;
}
if ((_n & 0x000000000000000FULL) == 0) {
_n >>= 4;
_v += 4;
}
if ((_n & 0x0000000000000003ULL) == 0) {
_n >>= 2;
_v += 2;
}
if ((_n & 0x0000000000000001ULL) == 0) {
_n >>= 1;
_v += 1;
}
return _v;
}
#endif
/*
* Find Last Set functions
*/
#ifndef fls32
static __inline int __unused
fls32(uint32_t _n)
{
int _v;
if (!_n)
return 0;
_v = 32;
if ((_n & 0xFFFF0000U) == 0) {
_n <<= 16;
_v -= 16;
}
if ((_n & 0xFF000000U) == 0) {
_n <<= 8;
_v -= 8;
}
if ((_n & 0xF0000000U) == 0) {
_n <<= 4;
_v -= 4;
}
if ((_n & 0xC0000000U) == 0) {
_n <<= 2;
_v -= 2;
}
if ((_n & 0x80000000U) == 0) {
_n <<= 1;
_v -= 1;
}
return _v;
}
#endif
#ifndef fls64
static __inline int __unused
fls64(uint64_t _n)
{
int _v;
if (!_n)
return 0;
_v = 64;
if ((_n & 0xFFFFFFFF00000000ULL) == 0) {
_n <<= 32;
_v -= 32;
}
if ((_n & 0xFFFF000000000000ULL) == 0) {
_n <<= 16;
_v -= 16;
}
if ((_n & 0xFF00000000000000ULL) == 0) {
_n <<= 8;
_v -= 8;
}
if ((_n & 0xF000000000000000ULL) == 0) {
_n <<= 4;
_v -= 4;
}
if ((_n & 0xC000000000000000ULL) == 0) {
_n <<= 2;
_v -= 2;
}
if ((_n & 0x8000000000000000ULL) == 0) {
_n <<= 1;
_v -= 1;
}
return _v;
}
#endif
/*
* Integer logarithm, returns -1 on error. Inspired by the linux
* version written by David Howells.
*/
#define _ilog2_helper(_n, _x) ((_n) & (1ULL << (_x))) ? _x :
#define _ilog2_const(_n) ( \
_ilog2_helper(_n, 63) \
_ilog2_helper(_n, 62) \
_ilog2_helper(_n, 61) \
_ilog2_helper(_n, 60) \
_ilog2_helper(_n, 59) \
_ilog2_helper(_n, 58) \
_ilog2_helper(_n, 57) \
_ilog2_helper(_n, 56) \
_ilog2_helper(_n, 55) \
_ilog2_helper(_n, 54) \
_ilog2_helper(_n, 53) \
_ilog2_helper(_n, 52) \
_ilog2_helper(_n, 51) \
_ilog2_helper(_n, 50) \
_ilog2_helper(_n, 49) \
_ilog2_helper(_n, 48) \
_ilog2_helper(_n, 47) \
_ilog2_helper(_n, 46) \
_ilog2_helper(_n, 45) \
_ilog2_helper(_n, 44) \
_ilog2_helper(_n, 43) \
_ilog2_helper(_n, 42) \
_ilog2_helper(_n, 41) \
_ilog2_helper(_n, 40) \
_ilog2_helper(_n, 39) \
_ilog2_helper(_n, 38) \
_ilog2_helper(_n, 37) \
_ilog2_helper(_n, 36) \
_ilog2_helper(_n, 35) \
_ilog2_helper(_n, 34) \
_ilog2_helper(_n, 33) \
_ilog2_helper(_n, 32) \
_ilog2_helper(_n, 31) \
_ilog2_helper(_n, 30) \
_ilog2_helper(_n, 29) \
_ilog2_helper(_n, 28) \
_ilog2_helper(_n, 27) \
_ilog2_helper(_n, 26) \
_ilog2_helper(_n, 25) \
_ilog2_helper(_n, 24) \
_ilog2_helper(_n, 23) \
_ilog2_helper(_n, 22) \
_ilog2_helper(_n, 21) \
_ilog2_helper(_n, 20) \
_ilog2_helper(_n, 19) \
_ilog2_helper(_n, 18) \
_ilog2_helper(_n, 17) \
_ilog2_helper(_n, 16) \
_ilog2_helper(_n, 15) \
_ilog2_helper(_n, 14) \
_ilog2_helper(_n, 13) \
_ilog2_helper(_n, 12) \
_ilog2_helper(_n, 11) \
_ilog2_helper(_n, 10) \
_ilog2_helper(_n, 9) \
_ilog2_helper(_n, 8) \
_ilog2_helper(_n, 7) \
_ilog2_helper(_n, 6) \
_ilog2_helper(_n, 5) \
_ilog2_helper(_n, 4) \
_ilog2_helper(_n, 3) \
_ilog2_helper(_n, 2) \
_ilog2_helper(_n, 1) \
_ilog2_helper(_n, 0) \
-1)
#define ilog2(_n) \
( \
__builtin_constant_p(_n) ? _ilog2_const(_n) : \
((sizeof(_n) > 4 ? fls64(_n) : fls32(_n)) - 1) \
)
static __inline void
fast_divide32_prepare(uint32_t _div, uint32_t * __restrict _m,
uint8_t *__restrict _s1, uint8_t *__restrict _s2)
{
uint64_t _mt;
int _l;
_l = fls32(_div - 1);
_mt = (uint64_t)(0x100000000ULL * ((1ULL << _l) - _div));
*_m = (uint32_t)(_mt / _div + 1);
*_s1 = (_l > 1) ? 1 : _l;
*_s2 = (_l == 0) ? 0 : _l - 1;
}
/* ARGSUSED */
static __inline uint32_t
fast_divide32(uint32_t _v, uint32_t _div __unused, uint32_t _m, uint8_t _s1,
uint8_t _s2)
{
uint32_t _t;
_t = (uint32_t)(((uint64_t)_v * _m) >> 32);
return (_t + ((_v - _t) >> _s1)) >> _s2;
}
static __inline uint32_t
fast_remainder32(uint32_t _v, uint32_t _div, uint32_t _m, uint8_t _s1,
uint8_t _s2)
{
return _v - _div * fast_divide32(_v, _div, _m, _s1, _s2);
}
#define __BITMAP_TYPE(__s, __t, __n) struct __s { \
__t _b[__BITMAP_SIZE(__t, __n)]; \
}
#define __BITMAP_BITS(__t) (sizeof(__t) * NBBY)
#define __BITMAP_SHIFT(__t) (ilog2(__BITMAP_BITS(__t)))
#define __BITMAP_MASK(__t) (__BITMAP_BITS(__t) - 1)
#define __BITMAP_SIZE(__t, __n) \
(((__n) + (__BITMAP_BITS(__t) - 1)) / __BITMAP_BITS(__t))
#define __BITMAP_BIT(__n, __v) \
(1 << ((__n) & __BITMAP_MASK(*(__v)->_b)))
#define __BITMAP_WORD(__n, __v) \
((__n) >> __BITMAP_SHIFT(*(__v)->_b))
#define __BITMAP_SET(__n, __v) \
((__v)->_b[__BITMAP_WORD(__n, __v)] |= __BITMAP_BIT(__n, __v))
#define __BITMAP_CLR(__n, __v) \
((__v)->_b[__BITMAP_WORD(__n, __v)] &= ~__BITMAP_BIT(__n, __v))
#define __BITMAP_ISSET(__n, __v) \
((__v)->_b[__BITMAP_WORD(__n, __v)] & __BITMAP_BIT(__n, __v))
#if __GNUC_PREREQ__(2, 95)
#define __BITMAP_ZERO(__v) \
(void)__builtin_memset((__v), 0, sizeof(*__v))
#else
#define __BITMAP_ZERO(__v) do { \
size_t __i; \
for (__i = 0; __i < __arraycount(__v->_b); __i++) \
(__v)->_b[__i] = 0; \
} while (/* CONSTCOND */ 0)
#endif /* GCC 2.95 */
#endif /* _SYS_BITOPS_H_ */
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