Hi James, >On Mon, Jan 22, 2018 at 09:22:27AM -0600, Richard Biener wrote: >> It would be better to dissect this cost into vec_to_scalar and vec_extract >> where >> vec_to_scalar really means getting at the scalar value of a vector of >> uniform values >> which most targets can do without any instruction (just use a subreg). >> >> I suppose we could also make vec_to_scalar equal to vector extraction and >> remove >> the uses for the other case (reduction vector result to scalar reg). > > I have dug up Richard's comments from last year, which you appear to have > ignored and made no reference to when resubmitting the patch. > > Please don't do that. Carefully consider Richard's review feedback before > resubmitting this patch.
I seem to have missed this comment... However I can't see how it relates to my patch, particularly since Richard claimed in PR79262 that this PR is a backend issue. Sure it *would* be great to fix the vector cost infrastructure, but that's a lot of work, and wasn't my goal here, nor is it required to fix PR79262. The existing costs allow the issue to be solved, just like the other targets/tunings have done already, so that's clearly the best approach for this PR. Wilco
