Provides m_Argument that allows matching against a CallSite's specified argument. Provides m_Intrinsic pattern that can be templatized over the intrinsic id and bind/match arguments similarly to other pattern matchers. Implementations provided for 0 to 4 arguments, though it's very simple to extend for more. Also provides example template specialization for bswap (m_BSwap) and example of code cleanup for its use.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170091 91177308-0d34-0410-b5e6-96231b3b80d8
