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-rw-r--r--REORG.TODO/posix/sched_cpucount.c59
1 files changed, 59 insertions, 0 deletions
diff --git a/REORG.TODO/posix/sched_cpucount.c b/REORG.TODO/posix/sched_cpucount.c
new file mode 100644
index 0000000000..eaddf61b1b
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+++ b/REORG.TODO/posix/sched_cpucount.c
@@ -0,0 +1,59 @@
+/* Copyright (C) 2007-2017 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <limits.h>
+#include <sched.h>
+
+
+int
+__sched_cpucount (size_t setsize, const cpu_set_t *setp)
+{
+  int s = 0;
+  const __cpu_mask *p = setp->__bits;
+  const __cpu_mask *end = &setp->__bits[setsize / sizeof (__cpu_mask)];
+
+  while (p < end)
+    {
+      __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);
+      l = (l & 0x0f0f0f0f0f0f0f0ful) + ((l >> 4) & 0x0f0f0f0f0f0f0f0ful);
+      l = (l & 0x00ff00ff00ff00fful) + ((l >> 8) & 0x00ff00ff00ff00fful);
+      l = (l & 0x0000ffff0000fffful) + ((l >> 16) & 0x0000ffff0000fffful);
+      l = (l & 0x00000000fffffffful) + ((l >> 32) & 0x00000000fffffffful);
+# else
+      l = (l & 0x55555555ul) + ((l >> 1) & 0x55555555ul);
+      l = (l & 0x33333333ul) + ((l >> 2) & 0x33333333ul);
+      l = (l & 0x0f0f0f0ful) + ((l >> 4) & 0x0f0f0f0ful);
+      l = (l & 0x00ff00fful) + ((l >> 8) & 0x00ff00fful);
+      l = (l & 0x0000fffful) + ((l >> 16) & 0x0000fffful);
+# endif
+
+      s += l;
+#endif
+    }
+
+  return s;
+}