This is needed after running the SSAUpdater, because the updater can insert unnecessary phis in the middle of the original liverange of a value. Fixes an ownership error. rdar://153229472
...byWalkingDown
initialWalkingDirection
is_escaping_closure
destroy_not_escaped_closure
dealloc_stack
alloc_stack
UseList
SingleValueInstruction.replace(with:)
copy_addr
store