<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - Adding a single, meaningless if-else to a shader source leads to different image" href="https://bugs.freedesktop.org/show_bug.cgi?id=100303#c4">Comment # 4</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - Adding a single, meaningless if-else to a shader source leads to different image" href="https://bugs.freedesktop.org/show_bug.cgi?id=100303">bug 100303</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 Roland Scheidegger from <a href="show_bug.cgi?id=100303#c2">comment #2</a>) > > So, for some reason the compiler completely eliminated the conditional > return in the loop inside the branch and figured it will just > unconditionally return the value corresponding to not meeting that condition > in the loop in the original code. (In fact all code in this function with > the exception of the return statement is now effectively dead.) > Not sure though which lowering stage did this damage... I think there is a bug in do_lower_jumps(). I noticed a similar bug when working on loop unrolling for NIR. I wrote the following tests that pass on NIR unrolling/return lower but fail in GLSL IR. piglit/tests/spec/glsl-1.10/execution/vs-nested-return-sibling-loop.shader_tes piglit/tests/spec/glsl-1.10/execution/vs-nested-return-sibling-loop2.shader_test</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>