[ThinLTO] Look through aliases when computing hash keys

Without this, we don't consider types used by aliasees in our cache key.
This caused issues when using the same cache for thin-linking the same
TU with different sets of virtual call candidates for a virtual call
inside of a constructor. That's sort of a mouthful. :)

Differential Revision: https://reviews.llvm.org/D55060


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@348216 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed