Fixed a test that ensures the LocalRewriter does not attempt to

Fixed a test that ensures the LocalRewriter does not attempt to
avoid reloads by reusing clobbered registers.

This was causing issues in 256.bzip2 when compiled with PIC for
a while (starting at r78217), though the problem has since been masked.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80872 91177308-0d34-0410-b5e6-96231b3b80d8