R600: Take export into account when computing cf address

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178761 91177308-0d34-0410-b5e6-96231b3b80d8
R600: Fix wrong address when substituting ENDIF

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178762 91177308-0d34-0410-b5e6-96231b3b80d8
R600: Use a mask for offsets when encoding instructions

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178763 91177308-0d34-0410-b5e6-96231b3b80d8