Implement LaneBitmask::getNumLanes and LaneBitmask::getHighestLane

This should eliminate most uses of countPopulation and Log2_32 on
the lane mask values.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308658 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed