[MSSA] Print more optimization information

In particular, when asked to print a MemoryAccess, we'll now print where
defs are optimized to, and we'll print optimized access types.

This patch also introduces an operator<< to make printing AliasResults
easier.

Patch by Juneyoung Lee!

Differential Revision: https://reviews.llvm.org/D47860


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@334760 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed