On Tue, Jun 23, 2015 at 07:41:42PM +0100, Richard Sandiford wrote: > [A fair bit later than promised, sorry...] > > Mikhail posted a patch to make genflags generate the default HAVE_foo > and gen_foo definitions that have recently been added to defaults.h: > > https://gcc.gnu.org/ml/gcc-patches/2015-06/msg00723.html > > I agree it'd be a good idea to generate this kind of thing automatically, > but I think we should take the opportunity to move the interface to the > target structure. I.e.: > > HAVE_foo -> targetm.have_foo () > gen_foo -> targetm.gen_foo () > > This should move us closer to the pipedream goal of supporting multiple > targets at once. It should also mean that only the target code depends > on insn-flags.h.
using targetm. certainly seems like an improvement. I wonder if it would be faster to stick this data on a per function object. I think that would mean you could compute what insns are available once when the function is created and afterwards all checks would only needed to be reading computed values. Trev
