argument passing. Consolidate all SingletonRegister detection
and handling into a new
InstructionInfo::getSingletonRegisterForToken method instead of
having it scattered about. No change in generated .inc files.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117888 91177308-0d34-0410-b5e6-96231b3b80d8