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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 /posix/sched_cpucount.c
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.
Diffstat (limited to 'posix/sched_cpucount.c')
-rw-r--r--posix/sched_cpucount.c14
1 files changed, 9 insertions, 5 deletions
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);