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authorMichal Marek <mmarek@suse.cz>2010-08-04 13:59:13 +0200
committerMichal Marek <mmarek@suse.cz>2010-08-04 13:59:13 +0200
commit772320e84588dcbe1600ffb83e5f328f2209ac2a (patch)
treea7de21b79340aeaa17c58126f6b801b82c77b53a /lib/hweight.c
parent1ce53adf13a54375d2a5c7cdbe341b2558389615 (diff)
parent9fe6206f400646a2322096b56c59891d530e8d51 (diff)
Merge commit 'v2.6.35' into kbuild/kbuild
Conflicts: arch/powerpc/Makefile
Diffstat (limited to 'lib/hweight.c')
-rw-r--r--lib/hweight.c26
1 files changed, 17 insertions, 9 deletions
diff --git a/lib/hweight.c b/lib/hweight.c
index 389424ecb12..3c79d50814c 100644
--- a/lib/hweight.c
+++ b/lib/hweight.c
@@ -9,37 +9,45 @@
* The Hamming Weight of a number is the total number of bits set in it.
*/
-unsigned int hweight32(unsigned int w)
+unsigned int __sw_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);
+EXPORT_SYMBOL(__sw_hweight32);
-unsigned int hweight16(unsigned int w)
+unsigned int __sw_hweight16(unsigned int w)
{
unsigned int res = w - ((w >> 1) & 0x5555);
res = (res & 0x3333) + ((res >> 2) & 0x3333);
res = (res + (res >> 4)) & 0x0F0F;
return (res + (res >> 8)) & 0x00FF;
}
-EXPORT_SYMBOL(hweight16);
+EXPORT_SYMBOL(__sw_hweight16);
-unsigned int hweight8(unsigned int w)
+unsigned int __sw_hweight8(unsigned int w)
{
unsigned int res = w - ((w >> 1) & 0x55);
res = (res & 0x33) + ((res >> 2) & 0x33);
return (res + (res >> 4)) & 0x0F;
}
-EXPORT_SYMBOL(hweight8);
+EXPORT_SYMBOL(__sw_hweight8);
-unsigned long hweight64(__u64 w)
+unsigned long __sw_hweight64(__u64 w)
{
#if BITS_PER_LONG == 32
- return hweight32((unsigned int)(w >> 32)) + hweight32((unsigned int)w);
+ return __sw_hweight32((unsigned int)(w >> 32)) +
+ __sw_hweight32((unsigned int)w);
#elif BITS_PER_LONG == 64
#ifdef ARCH_HAS_FAST_MULTIPLIER
w -= (w >> 1) & 0x5555555555555555ul;
@@ -56,4 +64,4 @@ unsigned long hweight64(__u64 w)
#endif
#endif
}
-EXPORT_SYMBOL(hweight64);
+EXPORT_SYMBOL(__sw_hweight64);