This reverts commit r273160, reapplying r273132. RecursivelyDeleteTriviallyDeadInstructions cannot be called on a parentless Instruction. llvm-svn: 273162
This reverts commit r273160, reapplying r273132. RecursivelyDeleteTriviallyDeadInstructions cannot be called on a parentless Instruction. llvm-svn: 273162