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authorRussell King <rmk+kernel@arm.linux.org.uk>2010-03-08 20:21:04 +0000
committerRussell King <rmk+kernel@arm.linux.org.uk>2010-03-08 20:21:04 +0000
commit988addf82e4c03739375279de73929580a2d4a6a (patch)
tree989ae1cd4e264bbad80c65f04480486246e7b9f3 /lib/hweight.c
parent004c1c7096659d352b83047a7593e91d8a30e3c5 (diff)
parent25cf84cf377c0aae5dbcf937ea89bc7893db5176 (diff)
Merge branch 'origin' into devel-stable
Conflicts: arch/arm/mach-mx2/devices.c arch/arm/mach-mx2/devices.h sound/soc/pxa/pxa-ssp.c
Diffstat (limited to 'lib/hweight.c')
-rw-r--r--lib/hweight.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/lib/hweight.c b/lib/hweight.c
index 389424ecb129..63ee4eb1228d 100644
--- a/lib/hweight.c
+++ b/lib/hweight.c
@@ -11,11 +11,18 @@
unsigned int hweight32(unsigned int w)
{
+#ifdef ARCH_HAS_FAST_MULTIPLIER
+ w -= (w >> 1) & 0x55555555;
+ w = (w & 0x33333333) + ((w >> 2) & 0x33333333);
+ w = (w + (w >> 4)) & 0x0f0f0f0f;
+ return (w * 0x01010101) >> 24;
+#else
unsigned int res = w - ((w >> 1) & 0x55555555);
res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
res = (res + (res >> 4)) & 0x0F0F0F0F;
res = res + (res >> 8);
return (res + (res >> 16)) & 0x000000FF;
+#endif
}
EXPORT_SYMBOL(hweight32);