On Mon, Nov 15, 2021 at 4:01 PM Robin Murphy <robin.murphy@xxxxxxx> wrote: > On 2021-11-15 11:20, Andy Shevchenko wrote: > > Use BIT() as __GENMASK() is for internal use only. The rationale > > of switching to BIT() is to provide better generated code. The > > GENMASK() against non-constant numbers may produce an ugly assembler > > code. On contrary the BIT() is simply converted to corresponding shift > > operation. > > FWIW, If you care about code quality and want the compiler to do the > obvious thing, why not specify it as the obvious thing: > > u32 val = ~0 << msi->legacy_shift; Obvious and buggy (from the C standard point of view)? :-) > Personally I don't think that abusing BIT() in the context of setting > multiple bits is any better than abusing __GENMASK()... No, BIT() is not abused here, but __GENMASK(). After all it's up to you, folks, consider that as a bug report. -- With Best Regards, Andy Shevchenko
