[Piglit] [PATCH] glsl-1.20: Add tests exposing some crashes with const arrays

[Chris Forbes]

Note: this patch was pushed a few days ago, with Ilia's off-list R-b.
I'll do the follow-up work in a new patch.

On Fri, Nov 21, 2014 at 2:51 PM, Chris Forbes <chrisf at ijw.co.nz> wrote:
> Yep, I'll make execution versions of these, and an FS variant. Our FS
> backend wasn't hitting an assert if you did this, but didn't do the
> right thing.
>
> On Fri, Nov 21, 2014 at 1:35 PM, Ian Romanick <idr at freedesktop.org> wrote:
>> On 11/07/2014 10:43 AM, Chris Forbes wrote:
>>> I stumbled across these while implementing tessellation. In particular,
>>> the first test is a cutdown version of the tessellation nop.shader_test.
>>>
>>> The crash in array-initializers-1 is caused by the lowering of const arrays to
>>> uniforms. The hidden uniforms for both are named 'constarray', and a
>>> later phase in the linker gets horribly confused when it tries to look
>>> them up by name.
>>>
>>> I have not yet usefully characterized the crash in double-indirect-1,
>>> other than that it is in the i965 backend rather than in the GLSL
>>> compiler.
>>
>> Oof.  These look like good tests to have... it seems like it would be
>> pretty easy to make them execution tests.  Who knows what dragons may be
>> there...
>>
>>> Signed-off-by: Chris Forbes <chrisf at ijw.co.nz>
>>> ---
>>>
>>> Here's a slightly better version of the patch. The first crash turned out to be
>>> nothing to do with double-indirection.
>>>
>>>  tests/all.py                                        |  4 ++++
>>>  .../linker/array-initializers-1.shader_test         | 20 ++++++++++++++++++++
>>>  .../glsl-1.20/linker/double-indirect-1.shader_test  | 21 +++++++++++++++++++++
>>>  3 files changed, 45 insertions(+)
>>>  create mode 100644 tests/spec/glsl-1.20/linker/array-initializers-1.shader_test
>>>  create mode 100644 tests/spec/glsl-1.20/linker/double-indirect-1.shader_test
>>>
>>> diff --git a/tests/all.py b/tests/all.py
>>> index 4089325..3f004ce 100644
>>> --- a/tests/all.py
>>> +++ b/tests/all.py
>>> @@ -1074,6 +1074,10 @@ spec['glsl-1.20']['execution'] = {}
>>>  add_shader_test_dir(spec['glsl-1.20']['execution'],
>>>                      os.path.join(testsDir, 'spec', 'glsl-1.20', 'execution'),
>>>                      recursive=True)
>>> +spec['glsl-1.20']['linker'] = {}
>>> +add_shader_test_dir(spec['glsl-1.20']['linker'],
>>> +                    os.path.join(testsDir, 'spec', 'glsl-1.20', 'linker'),
>>> +                    recursive=True)
>>>  add_shader_test_dir(spec['glsl-1.20']['execution'],
>>>                      os.path.join(generatedTestDir, 'spec', 'glsl-1.20', 'execution'),
>>>                      recursive=True)
>>> diff --git a/tests/spec/glsl-1.20/linker/array-initializers-1.shader_test b/tests/spec/glsl-1.20/linker/array-initializers-1.shader_test
>>> new file mode 100644
>>> index 0000000..911acd4
>>> --- /dev/null
>>> +++ b/tests/spec/glsl-1.20/linker/array-initializers-1.shader_test
>>> @@ -0,0 +1,20 @@
>>> +# Demonstrates a crash in mesa.
>>> +
>>> +[require]
>>> +GLSL >= 1.20
>>> +
>>> +[vertex shader]
>>> +#version 120
>>> +
>>> +const int xs[] = int[](1,2,3);
>>> +const int ys[] = int[](1,2);
>>> +
>>> +uniform int n;
>>> +
>>> +void main()
>>> +{
>>> +  gl_Position = vec4(xs[n]+ys[n], 0, 0, 1);
>>> +}
>>> +
>>> +[test]
>>> +link success
>>> diff --git a/tests/spec/glsl-1.20/linker/double-indirect-1.shader_test b/tests/spec/glsl-1.20/linker/double-indirect-1.shader_test
>>> new file mode 100644
>>> index 0000000..c1d46e3
>>> --- /dev/null
>>> +++ b/tests/spec/glsl-1.20/linker/double-indirect-1.shader_test
>>> @@ -0,0 +1,21 @@
>>> +# Demonstrates a crash in i965. The double indirection via const arrays
>>> +# is required to trigger this.
>>> +
>>> +[require]
>>> +GLSL >= 1.20
>>> +
>>> +[vertex shader]
>>> +#version 120
>>> +
>>> +const float a[] = float[](0);
>>> +const int b[] = int[](0);
>>> +
>>> +uniform int n;
>>> +
>>> +void main()
>>> +{
>>> +  gl_Position = vec4(a[b[n]], 0, 0, 1);
>>> +}
>>> +
>>> +[test]
>>> +link success
>>>
>>