[Hexagon] Bitwise operations for insert/extract word not simplified

Change the bit simplifier to generate REG_SEQUENCE instructions in
addition to COPY, which will handle cases of word insert/extract.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276787 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed