<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - Convert phi nodes to logical operations" href="https://bugs.freedesktop.org/show_bug.cgi?id=94747#c4">Comment # 4</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - Convert phi nodes to logical operations" href="https://bugs.freedesktop.org/show_bug.cgi?id=94747">bug 94747</a> from <a class="email" href="mailto:t_arceri@yahoo.com.au" title="Timothy Arceri <t_arceri@yahoo.com.au>"> Timothy Arceri</a> <pre>(In reply to Ian Romanick from <a href="show_bug.cgi?id=94747#c3">comment #3</a>) > (In reply to Timothy Arceri from <a href="show_bug.cgi?id=94747#c2">comment #2</a>) > > As (In reply to Jason Ekstrand from <a href="show_bug.cgi?id=94747#c1">comment #1</a>) > > > The code for this already exists. It's called nir_opt_peephole_select. The > > > only problem is that it only triggers if both sides of the if are empty. > > > I've been wanting to add some sort of heuristic to it for some time now. > > > The only problem is that it's really back-end specific. > > > > Although i965 doesn't use it I believe this is otherwise fixed by the > > following commit. We should probably close this bug: > > Thanks for reminding me about these "don't forget" bugs that I filed. :) I > clearly forgot about them anyway. > > I have a patch for this that has been on the list for almost 3 weeks. > > <a href="https://patchwork.freedesktop.org/patch/233182/">https://patchwork.freedesktop.org/patch/233182/</a> > > That will just eliminate the flow control (but it might not since there are > 2 instructions... I wish I could remember which shader this was). Even then > we'll get something like > > ssa_177 = ssa_153 ? true : abs(ssa_171 - ssa_135) >= ssa_145 > > when we really want (ssa_153 || (abs(ssa_171 - ssa_135) >= ssa_145)). I > have another patch series in progress that will take care of that. I suspect we have been working on similar changes. I've just sent a series that should cover this also. <a href="https://patchwork.freedesktop.org/series/46827/">https://patchwork.freedesktop.org/series/46827/</a></pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>