On Wed, Jul 03, 2019 at 02:36:11PM -0400, Michael Meissner wrote: > On Wed, Jul 03, 2019 at 12:55:41PM -0500, Segher Boessenkool wrote: > > I don't think this is a good idea. You can set "cost" directly, if that > > is the only thing you need this for? > > The trouble is the cost is currently a factor based on type + the cost from > the > cost structure. It really would be hard to set it to a single value in the > insns without having to have complex means for setting the machine dependent > costs. If the numeric RTL attributes could set the value from a function, it > would be simpler, but that isn't currently supported.
(set (attr "cost") (symbol_ref "any C expression you want here")) It is supported. The syntax is a bit weird, sure :-) It may well be that some helper attribute can help here, but just num_insns isn't it. Segher
