tests: fix order of memory accesses to ensure import succeeds

It seems the order in which we generated memory accesses changed such that
the import of these updated memory accesses failed for the 'loop3' statement
in this test case. Unfortunately, the existing CHECK lines were not strict
enough to catch this. Hence, besides fixing the order of the memory access
lines we also ensure that the memory access changes are both clearly visibly
and well checked.

llvm-svn: 276247