Revert "MachineInstr: Reason locally about some memory objects before going to AA."

r310825 caused the clang-ppc64le-linux-lnt bot to go red
(http://lab.llvm.org:8011/builders/clang-ppc64le-linux-lnt/builds/5712)
because of a test-suite failure of
SingleSource/UnitTests/2003-07-09-SignedArgs

This reverts commit 0028f6a87224fb595a1c19c544cde9b003035996.

llvm-svn: 311008