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authorLinus Torvalds <torvalds@linux-foundation.org>2010-05-18 09:17:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-18 09:17:01 -0700
commitcb41838bbc4403f7270a94b93a9a0d9fc9c2e7ea (patch)
tree0f359975ccad4ac72e86b8edf1924c076e74bd89 /lib
parent98f01720cbe3e2eb719682777049b6514e9db556 (diff)
parentc59bd5688299cddb71183e156e7a3c1409b90df2 (diff)
Merge branch 'core-hweight-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-hweight-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, hweight: Use a 32-bit popcnt for __arch_hweight32() arch, hweight: Fix compilation errors x86: Add optimized popcnt variants bitops: Optimize hweight() by making use of compile-time evaluation
Diffstat (limited to 'lib')
-rw-r--r--lib/Makefile3
-rw-r--r--lib/hweight.c19
2 files changed, 13 insertions, 9 deletions
diff --git a/lib/Makefile b/lib/Makefile
index af759f39d4a..9e6d3c29d73 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -39,7 +39,10 @@ lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o
lib-$(CONFIG_GENERIC_FIND_FIRST_BIT) += find_next_bit.o
lib-$(CONFIG_GENERIC_FIND_NEXT_BIT) += find_next_bit.o
obj-$(CONFIG_GENERIC_FIND_LAST_BIT) += find_last_bit.o
+
+CFLAGS_hweight.o = $(subst $(quote),,$(CONFIG_ARCH_HWEIGHT_CFLAGS))
obj-$(CONFIG_GENERIC_HWEIGHT) += hweight.o
+
obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o
obj-$(CONFIG_BTREE) += btree.o
obj-$(CONFIG_DEBUG_PREEMPT) += smp_processor_id.o
diff --git a/lib/hweight.c b/lib/hweight.c
index 63ee4eb1228..3c79d50814c 100644
--- a/lib/hweight.c
+++ b/lib/hweight.c
@@ -9,7 +9,7 @@
* 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;
@@ -24,29 +24,30 @@ unsigned int hweight32(unsigned int w)
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;
@@ -63,4 +64,4 @@ unsigned long hweight64(__u64 w)
#endif
#endif
}
-EXPORT_SYMBOL(hweight64);
+EXPORT_SYMBOL(__sw_hweight64);