mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/
synced 2026-09-14 18:22:56 +00:00
Based on patch from David Rientjes <rientjes@google.com>, but changed by AK. Optimizes the 64-bit hamming weight for x86_64 processors assuming they have fast multiplication. Uses five fewer bitops than the generic hweight64. Benchmark on one EMT64 showed ~25% speedup with 2^24 consecutive calls. Define a new ARCH_HAS_FAST_MULTIPLIER that can be set by other architectures that can also multiply fast. Signed-off-by: Andi Kleen <ak@suse.de>
59 lines
1.6 KiB
59 lines
1.6 KiB