MemCpyOpt: combine local load/store sequences into memcpy.

Sort of the BB-local equivalent to idiom-recognizer: if we have a basic-block
that really implements a memcpy operation, backends can benefit from seeing
this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269125 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed