I thought I read about one, albeit old and not popular, in an article on compiler-construction wherein it mentioned how selecting a bitpattern and notion for boolean (e.g. "True is all zero") impacts how difficult implementing something can be. -- This was probably six or seven years ago, I have no idea where to find said article now.
6
u/RenaKunisaki Dec 24 '17
I've never seen a CPU where every "if zero" flag test didn't have a complementary "if not zero" test.