On Wed, Aug 23, 2017 at 11:49:03AM +0100, Richard Sandiford wrote: > This patch uses df_read_modify_subreg_p to check whether writing > to a subreg would preserve some of the existing contents.
combine does not keep the DF info up-to-date -- but that is no problem here, df_read_modify_subreg_p uses no DF info at all. Maybe it should not have "df_" in the name? Segher
