Convert INSERT_SUBREG to COPY in TwoAddressInstructionPass.

INSERT_SUBREG will now only appear in SSA machine instructions.

Fix the handling of partial redefs in ProcessImplicitDefs. This is now relevant
since partial redef COPY instructions appear.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107726 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed