On Wed, 8 May 2019, Segher Boessenkool wrote: > On Wed, May 08, 2019 at 02:20:19PM +0200, Richard Biener wrote: > > Btw, I wonder if on RTL basic-block reordering (which also does > > some tail duplication) could be a place to do such transform? > > Or is it too late to do the desired cleanups after that? > > Possibly since we're after RA. > > It is *much* too late; it is too late to do it at combine time, already > (and combine of course cannot do this). You need the early RTL passes to > clean up all that mess the conditionals generate -- the point of this patch > is to never have that conditional-to-integer-reg stuff to begin with. > > RTL isn't nice for doing cross-BB transforms, either.
Ah, well - I thought it works reasonably well for extended BBs ;) We can of course also match this at RTL expansion time but exposing this earlier definitely looks valuable. Richard.
