Re: [Mesa-dev] Compiling of shader gets stuck in infinite loop

2014-09-12 Thread Mike Stroyan
This extremely slow compilation is not actually an infinite loop. But the compile time does increase with every unrolled loop step in the shader. The time to complete is 2^N, where N is the number of loop iterations. The call to (*rvalue)-accept(this); in

[Mesa-dev] Compiling of shader gets stuck in infinite loop

2014-09-11 Thread Iago Toral Quiroga
Hi, I have been looking into this bug: Compiling of shader gets stuck in infinite loop https://bugs.freedesktop.org/show_bug.cgi?id=78468 Although this occurs at link time when the Intel driver has run some of its specific lowering passes, it looks like the problem could hit other drivers if

Re: [Mesa-dev] Compiling of shader gets stuck in infinite loop

2014-09-11 Thread Mike Stroyan
I have looked at this problem quite a bit but never got to the bottom of it. This problem really started to show with commit 857f3a6 - glsl: Ignore loop-too-large heuristic if there's bad variable indexing. That commit makes many more loops unroll. Here is another example piglit shader_runner test