Make StringRef::getAsInteger work with all integer types. Before this change
it would fail with {,u}int64_t on x86-64 Linux.

This also removes code duplication.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152517 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed