(if there are any) and use the one which remains available for the longest
rather than just using the first one. This should help enable better re-use
of the loaded frame index values. rdar://7318760
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107847 91177308-0d34-0410-b5e6-96231b3b80d8