Revert these. They may have been causing 483_xalancbmk to fail:
$ svn merge -c -91161 https://llvm.org/svn/llvm-project/llvm/trunk
--- Reverse-merging r91161 into '.':
U lib/CodeGen/BranchFolding.cpp
U lib/CodeGen/MachineBasicBlock.cpp
$ svn merge -c -91113 https://llvm.org/svn/llvm-project/llvm/trunk
--- Reverse-merging r91113 into '.':
G lib/CodeGen/MachineBasicBlock.cpp
$ svn merge -c -91101 https://llvm.org/svn/llvm-project/llvm/trunk
--- Reverse-merging r91101 into '.':
U include/llvm/CodeGen/MachineBasicBlock.h
G lib/CodeGen/MachineBasicBlock.cpp
$ svn merge -c -91092 https://llvm.org/svn/llvm-project/llvm/trunk
--- Reverse-merging r91092 into '.':
G include/llvm/CodeGen/MachineBasicBlock.h
G lib/CodeGen/MachineBasicBlock.cpp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91376
91177308-0d34-0410-b5e6-
96231b3b80d8