kernel/include/asm-generic/bitops/arch_hweight.h, branch linux-4.3.yHosts the 0x221E linux distro kernel.https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-4.3.y2010-05-04T17:25:27Zarch, hweight: Fix compilation errors2010-05-04T17:25:27ZBorislav Petkovborislav.petkov@amd.com2010-05-03T12:57:11Zurn:sha1:4677d4a53e0d565742277e8913e91c821453e63e
Fix function prototype visibility issues when compiling for non-x86
architectures. Tested with crosstool
(ftp://ftp.kernel.org/pub/tools/crosstool/) with alpha, ia64 and sparc
targets.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <20100503130736.GD26107@aftab>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86: Add optimized popcnt variants2010-04-06T22:52:11ZBorislav Petkovborislav.petkov@amd.com2010-03-05T16:34:46Zurn:sha1:d61931d89be506372d01a90d1755f6d0a9fafe2d
Add support for the hardware version of the Hamming weight function,
popcnt, present in CPUs which advertize it under CPUID, Function
0x0000_0001_ECX[23]. On CPUs which don't support it, we fallback to the
default lib/hweight.c sw versions.
A synthetic benchmark comparing popcnt with __sw_hweight64 showed almost
a 3x speedup on a F10h machine.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
LKML-Reference: <20100318112015.GC11152@aftab>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
bitops: Optimize hweight() by making use of compile-time evaluation2010-04-06T22:52:11ZPeter Zijlstraa.p.zijlstra@chello.nl2010-02-01T14:03:07Zurn:sha1:1527bc8b928dd1399c3d3467dd47d9ede210978a
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>