[PATCH] use register iterators that include self to reduce code duplication in CriticalAntiDepBreaker

[Sanjay Patel]

Thanks for looking this over! 
Yes, those asserts look bogus - the only way they could fire is if Count is ~0u since we're setting both Kills and Defs right ahead of the asserts. I'll remove them.

http://reviews.llvm.org/D4566