> Just the fact that the backends that get most attention and attract > most developers don't use cc0 doesn't mean cc0 is a useless device.
Everything that can be done with cc0 can be done with the new representation, at least theoritically, although this can require more work. > As far as cc0 is concerned, transforming avr BE is not trivial. > It would need rewriting almost all of its md files entirely. > It would need rewriting great deal of avr.c that handle > insn output and provide input to NOTICE_UPDATE_CC. I recently converted the Visium port, which is an architecture where every integer instruction, including a simple move, clobber the flags, so it's doable even for such an annoying target (but Visium is otherwise regular). See for example https://gcc.gnu.org/wiki/CC0Transition for some guidelines. > But my feeling is that opposing deprecation of cc0 is futile, > the voices that support cc0 deprecation are more and usefulness > of cc0 is not recognized. cc0 is just obsolete and inferior compared to the new representation. -- Eric Botcazou