The previous tests claimed to test constant offsets in the function name,
but the tests weren't actually testing them.
Clone the tests, and do testing of all combinations of the following:
1) with/without constant pointer offset
2) 32/64-bit addressing modes
3) Usage and non-usage of the return value from the atomicrmw
Reviewed-by: Matt Arsenault <matthew.arsenault@amd.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220103 91177308-0d34-0410-b5e6-96231b3b80d8