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authorUlrich Drepper <drepper@redhat.com>2007-06-08 19:23:19 +0000
committerUlrich Drepper <drepper@redhat.com>2007-06-08 19:23:19 +0000
commit36dffb2256f4ad8fa45feaf0617d8c5570a92cdb (patch)
treec51054851ca82b4bc708c71252d8ba36ebbc5f51
parent7d0e41cebe87f807c70c65b9b8cb001edca66465 (diff)
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* posix/sched_cpucount.c (__sched_cpucount): Allow using special
instruction for counting bits. * sysdeps/x86_64/sched_cpucount.c: New file.
-rw-r--r--ChangeLog6
-rw-r--r--posix/sched_cpucount.c14
-rw-r--r--sysdeps/x86_64/sched_cpucount.c26
3 files changed, 41 insertions, 5 deletions
diff --git a/ChangeLog b/ChangeLog
index f7fff22599..f2ae8991df 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -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.
diff --git a/posix/sched_cpucount.c b/posix/sched_cpucount.c
index fd2687d8af..331c0b8dfc 100644
--- a/posix/sched_cpucount.c
+++ b/posix/sched_cpucount.c
@@ -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);
diff --git a/sysdeps/x86_64/sched_cpucount.c b/sysdeps/x86_64/sched_cpucount.c
new file mode 100644
index 0000000000..63d84a62e8
--- /dev/null
+++ b/sysdeps/x86_64/sched_cpucount.c
@@ -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>