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> |
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| .. | ||
| __ffs.h | ||
| __fls.h | ||
| arch_hweight.h | ||
| atomic.h | ||
| const_hweight.h | ||
| ext2-atomic.h | ||
| ext2-non-atomic.h | ||
| ffs.h | ||
| ffz.h | ||
| find.h | ||
| fls.h | ||
| fls64.h | ||
| hweight.h | ||
| le.h | ||
| lock.h | ||
| minix-le.h | ||
| minix.h | ||
| non-atomic.h | ||
| sched.h | ||