Summary:
These are all implemented by icc as well.
I made bit_scan_forward/reverse forward to the __bsfd/__bsrq since we also have
__bsfq/__bsrq.
Note, when lzcnt is enabled the bsr intrinsics generates lzcnt+xor instead of bsr.
Reviewers: RKSimon, spatel
Subscribers: cfe-commits, llvm-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D59682
llvm-svn: 356848