On Wed, Apr 29, 2020 at 08:56:11AM -0600, Jeff Law wrote: > On Tue, 2020-04-28 at 20:03 -0500, Segher Boessenkool wrote: > > What are the actual rules? Where is this documented? > > > > Of course it is highly desirable to have CONST around such constant > > addresses, but when is it *required*? And what *is* a constant address > > (in this context)? > I don't know if it's documented, but it's been expected practice for decades. > > It includes symbolic constants, and the results of simple arithmetic on > symbolic > constants. It (to the best of my knowledge) does not include logical > operations > on symbolic constants.
So should it be done for anything that is "i" as constraint? Or only for constant addresses? In what sense constant, anyway? None of this ever was clear to me... I always did the "if it doesn't ICE anymore, we're good" routine, but *everyone* seems to do that, and that isn't so optimal ;-) Segher
