Summary:
When people are really sure they'll get the lock they sometimes use
__builtin_expect. It's also used by some assertion implementations.
Asserting that try-lock succeeded is basically the same as asserting
that the lock is not held by anyone else (and acquiring it).
Reviewers: aaron.ballman, delesley
Reviewed By: aaron.ballman
Subscribers: kristina, cfe-commits
Differential Revision: https://reviews.llvm.org/D52398
llvm-svn: 343681
7146b0032f