multiplies.
Some more cleverness would be nice, though. It would be nice if we
could do this transformation on illegal types. Also, we would
prefer a narrower constant when possible so that we can use a narrower
multiply, which can be cheaper.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60283 91177308-0d34-0410-b5e6-96231b3b80d8
