This restores commit r260408, along with a fix for a bot failure.
The bot failure was caused by dereferencing a unique_ptr in the same
call instruction parameter list where it was passed via std::move.
Apparently due to luck this was not exposed when I built the compiler
with clang, only with gcc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260442 91177308-0d34-0410-b5e6-96231b3b80d8