https://bugs.freedesktop.org/show_bug.cgi?id=85579

--- Comment #1 from sarnex commendsarnex@gmail.com --- Created attachment 108603 --> https://bugs.freedesktop.org/attachment.cgi?id=108603&action=edit log when the test crashes

https://bugs.freedesktop.org/show_bug.cgi?id=85579

--- Comment #3 from sarnex commendsarnex@gmail.com --- Created attachment 108624 --> https://bugs.freedesktop.org/attachment.cgi?id=108624&action=edit patch crash

(In reply to Michel Dänzer from comment #2)

Created attachment 108612 [details] radeonsi: If compiling the vertex or geometry shader fails, skip the draw

Does this patch fix the crash?

Hi Michel,

Unfortunately, it appears the patch has no effect. But, after updating my mesa to today's version, the test crashes very quickly, when it used to take over 3 minutes to fail or crash. Maybe this is related to the other llvm change?

I attached a log.

Thanks, sarnex

https://bugs.freedesktop.org/show_bug.cgi?id=85579

--- Comment #5 from sarnex commendsarnex@gmail.com --- Created attachment 108646 --> https://bugs.freedesktop.org/attachment.cgi?id=108646&action=edit backtrace

(In reply to Michel Dänzer from comment #4)

Can you run the test in gdb and attach a backtrace? From the logs you attached, the command line for running the test on your system is:

/usr/local/lib/piglit/bin/shader_runner /usr/local/bin/../lib/piglit/tests/spec/glsl-1.50/execution/geometry/max- input-components.shader_test -auto

Hi Michel,

I compiled LLVM3.5 debug and Mesa debug, so hopefully there is enough information here. The backtrace is attached.

Thanks, sarnex

https://bugs.freedesktop.org/show_bug.cgi?id=85579

--- Comment #7 from sarnex commendsarnex@gmail.com --- Created attachment 108669 --> https://bugs.freedesktop.org/attachment.cgi?id=108669&action=edit second bt

(In reply to Michel Dänzer from comment #6)

(In reply to sarnex from comment #5)

...

I compiled LLVM3.5 debug and Mesa debug, so hopefully there is enough information here. The backtrace is attached.

That's a crash in LLVM. Does that also happen with Mesa commit 54de7099115502c561f5f51095e08dc0a52c71b7? If not, can you test my patch on top of that?

Nope, it's a different crash. I incorrectly assumed it would be the same crash since on latest git vs the first commit where it crashes.

Backtrace attached.

Thanks and sorry for the confusion. Sarnex

https://bugs.freedesktop.org/show_bug.cgi?id=85579

--- Comment #9 from Marek Olšák maraeo@gmail.com --- I think there are 2 ways to fix this and we should do both:

1) Fix VGPR register spilling caused by indirect addressing into lots of registers. LLVM crashes when it attempts to do that. Those registers are just copies of shader inputs and outputs.

2) Step A) Implement indirect addressing for VS outputs before GS and GS inputs. This means that we cannot store outputs at the end of shaders (using emit_epilogue), but we must store them when they occur as a destination register (using emit_store).

(BTW my tessellation branch contains modifications to emit_store that make it easier to re-implement it for shaders that use store instructions for outputs)

Step B) glsl_to_tgsi and/or some passes of the GLSL compiler may need to be modified not to move ins/outs into temporaries. I think the only pass that does that is the varying packing. The pass should be disabled or rewritten, because its current implementation isn't gonna fly with our hardware and is often the cause of unnecessary register spilling.