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* posix/sched_cpucount.c (__sched_cpucount): Allow using special

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instruction for counting bits.
	* sysdeps/x86_64/sched_cpucount.c: New file.
This commit is contained in:
Ulrich Drepper 2007-06-08 19:23:19 +00:00
parent 7d0e41cebe
commit 36dffb2256
3 changed files with 41 additions and 5 deletions
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6
ChangeLog
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@ -1,3 +1,9 @@
2007-06-08 Ulrich Drepper <drepper@redhat.com>
* posix/sched_cpucount.c (__sched_cpucount): Allow using special
instruction for counting bits.
* sysdeps/x86_64/sched_cpucount.c: New file.
2007-06-07 Ulrich Drepper <drepper@redhat.com>
* configure.in: Avoid variable named BASH.

14
posix/sched_cpucount.c
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@ -21,18 +21,22 @@
int
__sched_cpucount (size_t setsize, cpu_set_t *setp)
__sched_cpucount (size_t setsize, const cpu_set_t *setp)
{
int s = 0;
for (unsigned int j = 0; j < setsize / sizeof (__cpu_mask); ++j)
const __cpu_mask *p = setp->__bits;
const __cpu_mask *end = &setp->__bits[setsize / sizeof (__cpu_mask)];
while (p < end)
{
__cpu_mask l = setp->__bits[j];
if (l == 0)
continue;
__cpu_mask l = *p++;
#ifdef POPCNT
s += POPCNT (l);
#else
if (l == 0)
continue;
# if LONG_BIT > 32
l = (l & 0x5555555555555555ul) + ((l >> 1) & 0x5555555555555555ul);
l = (l & 0x3333333333333333ul) + ((l >> 2) & 0x3333333333333333ul);

26
sysdeps/x86_64/sched_cpucount.c Normal file
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@ -0,0 +1,26 @@
/* Copyright (C) 2007 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifdef __amdfam10
# define POPCNT(l) \
({ __cpu_mask r; \
asm ("popcntq %1, %0" : "=r" (r) : "0" (l)); \
r; })
#endif
#include <posix/sched_cpucount.c>