Fix pr13145 - Naming a function like a register name confuses the asm parser.
Patch by Stepan Dyatkovskiy <stpworld@narod.ru>
rdar://13457826

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177463 91177308-0d34-0410-b5e6-96231b3b80d8