[ARM] Add additional matching for UBFX instructions

This adds an additional matcher to select UBFX(..) from SRL(AND(..)) in
ARMISelDAGToDAG to help with code size.

Patch by David Green.

Differential Revision: http://reviews.llvm.org/D20667



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271384 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed