+ /// PopcntHwSupport - Hardware support for population count. Compared to the
+ /// SW implementation, HW support is supposed to significantly boost the
+ /// performance when the population is dense, and it may or not may degrade
+ /// performance if the population is sparse. A HW support is considered as
+ /// "Fast" if it can outperform, or is on a par with, SW implementaion when
+ /// the population is sparse; otherwise, it is considered as "Slow".
+ enum PopcntHwSupport {
+ None,
+ Fast,
+ Slow
+ };
+