LivePhysRegs: Fix addLiveOutsNoPristines() for return blocks past PEI

- addLiveOutsNoPristines() needs to add callee saved registers that are
  actually saved and restored somewhere to the set (they are not
  pristine).
- Cleanup/rewrite the code for addLiveOuts()/addLiveOutsNoPristines().

This fixes the problem from D32156.

Differential Revision: https://reviews.llvm.org/D32464

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303938 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed