> > On 3/5/23 12:28, Tamar Christina via Gcc-patches wrote: > > > > The regression was reported during stage-1. A patch was provided during > stage 1 and the discussions around combine stalled. > > > > The regression for AArch64 needs to be fixed in GCC 13. The hit is too big > > just > to "take". > > > > So we need a way forward, even if it's stage-4. > Then it needs to be in a way that works within the design constraints of > combine. > > As Segher has indicated, using a magic constant to say "this is always cheap > enough" isn't acceptable. Furthermore, what this patch changes is combine's > internal canonicalization of extensions into shift pairs. > > So I think another path forward needs to be found. I don't see hacking up > expand_compound_operation is viable.
I'm not arguing at all about the merits of the patch. My argument was about Segher saying he doesn't think this is a P1 regression or one that should be addressed in stage-4. We noticed and reported the regression early on during stage-1. So I'm unsure what else we should have done and it's not right to waive off fixing it now, otherwise what's the point in us filing bug reports. Tamar. > > Jeff
