Summary:
Without these patterns we would generate a complete LL/SC sequence.
This would be problematic for memory regions marked as WRITE-only or
READ-only, as the instructions LL/SC would read/write to the protected
memory regions correspondingly.
Reviewers: dsanders
Subscribers: llvm-commits, dsanders
Differential Revision: http://reviews.llvm.org/D14397
llvm-svn: 252293
Vasileios Kalintiris