[Bug 100134] Decreasing for loops over shared arrays hang the GPU (GEN9)

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=100134

            Bug ID: 100134
           Summary: Decreasing for loops over shared arrays hang the GPU
                    (GEN9)
           Product: Mesa
           Version: 13.0
          Hardware: Other
                OS: All
            Status: NEW
          Severity: normal
          Priority: medium
         Component: Drivers/Vulkan/intel
          Assignee: intel-3d-bugs at lists.freedesktop.org
          Reporter: freiling at google.com
        QA Contact: intel-3d-bugs at lists.freedesktop.org
                CC: jason at jlekstrand.net

Created attachment 130135
  --> https://bugs.freedesktop.org/attachment.cgi?id=130135&action=edit
Offending SPIR-V

We have a very simple glsl compute shader which hangs gen9

#version 450
#extension GL_ARB_separate_shader_objects : enable

shared int roi[8];

void main() {
  for (uint i = 7; i >= 0; i--) {
    roi[i] = 1;
  }
}

Heres some things we know about it

-changing the loop condition to "for (uint i = 0; i < 8; i++)" fixes the
problem
-making roi a function scoped "local" variable fixes the problem
-the spir-v we get out of GLSLang looks legit afaict (attached for your
reference)
-the same spir-v works on nvidia

Let us know if you have any questions.


Forrest

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/intel-3d-bugs/attachments/20170308/2d8f7bcf/attachment.html>