add new isSingleStringRef()/getSingleStringRef() methods to twine, 
and use them to avoid a copy of a string in getNameWithPrefix in
the common case.  It seems like Value::setName and other places 
should use this as well?

llvm-svn: 93301
2 files changed
tree: f7a587bc98f0c154f0e804d711713a30958e57d5
  1. clang/
  2. compiler-rt/
  3. llvm/