On Mon, Nov 12, 2018 at 05:52:25PM +0000, Andrew Stubbs wrote: > On 12/11/2018 17:20, Segher Boessenkool wrote: > >If you don't want useless USEs deleted, use UNSPEC_VOLATILE instead? > >Or actually use the register, i.e. as input to an actually needed > >instruction. > > They're not useless.
> >If combine is changing an X and a USE to just that X if it can, combine > >is doing a great job! Actually, it is incorrect to delete a USE. Please open a PR. Thanks. Segher
