[IR][AssumptionCache] Add m_Shift and m_BitwiseLogic matchers to replace a couple m_CombineOr

Summary:
m_CombineOr isn't very efficient. The code using it is also quite verbose.

This patch adds m_Shift and m_BitwiseLogic matchers to make the using code more concise and improve the match efficiency.

Reviewers: spatel, davide

Reviewed By: davide

Subscribers: davide, llvm-commits

Differential Revision: https://reviews.llvm.org/D34593

llvm-svn: 306206