Previously reverted in rL343082.
Original commit message:
On failing to find sequences that can be converted into dual macs,
try to find sequential 16-bit loads that are used by muls which we
can then use smultb, smulbt, smultt with a wide load.
Differential Revision: https://reviews.llvm.org/D51983
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344693 91177308-0d34-0410-b5e6-96231b3b80d8