[CGP] use narrower types in memcmp expansion when possible

This only affects very small memcmp on x86 for now, but it
will become more important if we allow vector-sized load and
compares.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309711 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed