implement iteration over ones in elias_fano
elias-fano scanning perftest
Implement specialized unary enumerator for elias_fano enumeration
Optimize select enumeration in elias_fano
In elias_fano perftest, use small-space generation of monotone sequences
minor
move unary_enumerator to bit_vector class, fix initialization in elias_fano select_enumerator
minor optimizations
fix compilation when intrinsics are disabled
simplify the broadword MSB algorithm for platforms with intrinsics disabled
Make libc++ with Clang optional