[ovs-dev] [PATCH 2/2] util: Make popcount() handle 64-bit integers, not separate popcount64().

[Jarno Rajahalme]

>> On Nov 18, 2013, at 1:19 PM, Ben Pfaff <blp at nicira.com> wrote:
>> 
>> This also restores use, in practice, of the optimized implementation of
>> population count.  (As the comment on popcount32() says, this version is
>> 2x faster than __builtin_popcount().)
>> 

I just tested the builtin popcountll with -march=native on i7. It is about 4x faster than our current version and about 8x faster than the builtin on a generic build.

  Jarno