https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92342
--- Comment #7 from Segher Boessenkool <segher at gcc dot gnu.org> --- (In reply to Richard Earnshaw from comment #5) > So if the AND-based idiom is now preferred, shouldn't the if-then-else > variant be transformed into it? Neither form is canonical currently. The form you *really* want tests a CCmode var, but combine will not give you that (unless it started with one), so you'll need md patterns for it. > Similarly for IOR, when we get > > (IOR (NEG (<cond-op>)) (reg)) > > from > > (IF_THEN_ELSE (<cond-op>) > (reg) > (const_int -1)) Yeah. And some more variants. I think the IF_THEN_ELSE version should be canonical, and it should be formed in simplify_rtx, not at random spots in combine.
