<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - Too many temporary expressions in shader freeze glLinkProgram" href="https://bugs.freedesktop.org/show_bug.cgi?id=94477#c8">Comment # 8</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - Too many temporary expressions in shader freeze glLinkProgram" href="https://bugs.freedesktop.org/show_bug.cgi?id=94477">bug 94477</a> from <a class="email" href="mailto:mattst88@gmail.com" title="Matt Turner <mattst88@gmail.com>"> Matt Turner</a> <pre>(In reply to Tapani Pälli from <a href="show_bug.cgi?id=94477#c6">comment #6</a>) > Created <a href="attachment.cgi?id=126170" name="attach_126170" title="fix">attachment 126170</a> <a href="attachment.cgi?id=126170&action=edit" title="fix">[details]</a> <a href='page.cgi?id=splinter.html&bug=94477&attachment=126170'>[review]</a> [review] > fix > > This should result in same effect as the first experimentation, I will run > testing on this and if it works fine then I'll send it to mesa-dev mailing > list. That's pretty clever, but unfortunately it cannot work. Cases of dividing by zero, inf, nan, etc cannot be handled. We don't do this optimization in opt_algebraic for exactly that reason. On top of that, the purpose of the test is to check whether you can compile a huge expression, and the one it uses is hilariously unrepresentative and prone to abuse by hacks like this one :) The test has uncovered real flaws in our compiler: GLSL IR's copy propagation runs in O(n^2), and the channel_expressions pass creates a huge number of expressions. Ken and I have spent time recently trying to handle the shader-db regressions by disabling channel_expressions. It's slow going and other tasks keep taking priority. The most direct way forward then, is to improve copy propagate's run time like I described in <a href="show_bug.cgi?id=94477#c3">comment 3</a>. Maybe you want to take a stab at replacing the linked lists in the pass with hash tables? I spent some time on it... maybe you'll have better luck. :)</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>