Mesa (master): gallium/util: add util_bitcount64

[Marek Olšák]

Module: Mesa
Branch: master
Commit: af4f5a7c97f3ab47bbd21aa7c27d0c0aaf01f959
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=af4f5a7c97f3ab47bbd21aa7c27d0c0aaf01f959

Author: Marek Olšák <marek.olsak at amd.com>
Date:   Wed Sep 24 18:26:21 2014 +0200

gallium/util: add util_bitcount64

I'll need this in radeonsi.

v2: use __builtin_popcountll if available

Reviewed-by: Michel Dänzer <michel.daenzer at amd.com>

---

 src/gallium/auxiliary/util/u_math.h |   12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/gallium/auxiliary/util/u_math.h b/src/gallium/auxiliary/util/u_math.h
index 39bd40f..f95c111 100644
--- a/src/gallium/auxiliary/util/u_math.h
+++ b/src/gallium/auxiliary/util/u_math.h
@@ -727,6 +727,18 @@ util_bitcount(unsigned n)
 #endif
 }
 
+
+static INLINE unsigned
+util_bitcount64(uint64_t n)
+{
+#ifdef HAVE___BUILTIN_POPCOUNTLL
+   return __builtin_popcountll(n);
+#else
+   return util_bitcount(n) + util_bitcount(n >> 32);
+#endif
+}
+
+
 /**
  * Reverse bits in n
  * Algorithm taken from: