Re-land the change r238200, but with modifications in the tests that should
prevent new failures in some environments as reported with the original
change on the mailing list.
llvm-svn: 238253
On MIPS unsigned int type should not be zero extended but sign-extended.
Patch by Strahinja Petrovic.
Differential Revision: http://reviews.llvm.org/D9198
llvm-svn: 238200