Ping for some minor cleanups that help with the move to variable-length modes. Segher has approved the combine.c parts (thanks).
https://gcc.gnu.org/ml/gcc-patches/2017-08/msg01339.html Make more use of HWI_COMPUTABLE_MODE_P https://gcc.gnu.org/ml/gcc-patches/2017-08/msg01452.html Make more use of read_modify_subreg_p https://gcc.gnu.org/ml/gcc-patches/2017-08/msg01343.html Make more use of subreg_lowpart_offset https://gcc.gnu.org/ml/gcc-patches/2017-08/msg01344.html Make more use of subreg_size_lowpart_offset https://gcc.gnu.org/ml/gcc-patches/2017-08/msg01345.html Make more use of byte_lowpart_offset Thanks, Richard
