<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - dEQP failures on llvmpipe" href="https://bugs.freedesktop.org/show_bug.cgi?id=94957#c9">Comment # 9</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - dEQP failures on llvmpipe" href="https://bugs.freedesktop.org/show_bug.cgi?id=94957">bug 94957</a> from <a class="email" href="mailto:sroland@vmware.com" title="Roland Scheidegger <sroland@vmware.com>"> Roland Scheidegger</a> <pre>So, the r32i/ui failures are actually due to an overflow. One example I've seen samples a rgb8 unorm texture, scales to int range, converts to int and outputs this. The problem is that rescaling to 2^31 - 1 really ends up with 2^31 due to imprecise float math, which causes an overflow when converted to an int. I'm nearly certain this is undefined behavior by the glsl spec, albeit the spec doesn't explicitly say so (but should probably follow from ieee754 math). d3d10 would require clamping, making it work. So, I'm inclined to say that's just a test bug. But even if it's undefined but all gpus clamp anyway we might want to fix it nonetheless...</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are the assignee for the bug.</li> </ul> </body> </html>