lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

bitops: Optimize hweight() by making use of compile-time evaluation

Browse Source 
Rename the extisting runtime hweight() implementations to
__arch_hweight(), rename the compile-time versions to __const_hweight()
and then have hweight() pick between them.

Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100318111929.GB11152@aftab>
Acked-by: H. Peter Anvin <hpa@zytor.com>
LKML-Reference: <1265028224.24455.154.camel@laptop>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
Peter Zijlstra
2010-02-01 15:03:07 +01:00
committed by H. Peter Anvin
parent 0fdf86754f
commit 1527bc8b92
8 changed files with 87 additions and 58 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
include/asm-generic/bitops/hweight.h
View File

@@ -1,11 +1,7 @@
#ifndef _ASM_GENERIC_BITOPS_HWEIGHT_H_
#define _ASM_GENERIC_BITOPS_HWEIGHT_H_
#include <asm/types.h>
extern unsigned int hweight32(unsigned int w);
extern unsigned int hweight16(unsigned int w);
extern unsigned int hweight8(unsigned int w);
extern unsigned long hweight64(__u64 w);
#include <asm-generic/bitops/arch_hweight.h>
#include <asm-generic/bitops/const_hweight.h>
#endif /* _ASM_GENERIC_BITOPS_HWEIGHT_H_ */