Don't let arbitrary calls disrupt nested retain+release pairs if
the retains and releases all use the same SSA pointer value.

Also, don't let CFG hazards disrupt nested retain+release pair
optimizations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137399 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed