[Piglit] [RFC PATCH] gl-3.1: Add test for trying to draw with a broken vertex attrib

[Chris Forbes]

This is one of the cases which doesn't explicitly allow program termination:

>From the OpenGL 4.5 (Core Profile) Specification, 10.3.9 Vertex Arrays
in Buffer Objects, p344:

"If any enabled array’s buffer binding is zero when DrawArrays
or one of the other drawing commands defined in section 10.4
is called, the result is undefined."


On Tue, Oct 21, 2014 at 7:19 AM, Ian Romanick <idr at freedesktop.org> wrote:
> On 10/16/2014 02:30 AM, Chris Forbes wrote:
>> This exercises a segfault in i965. Requires a vertex attribute
>> which is:
>>       - enabled
>>       - not sourced from anywhere
>>       - consumed by the vertex shader
>>
>> Signed-off-by: Chris Forbes <chrisf at ijw.co.nz>
>> ---
>>
>> I ran into this while fixing core profile support in the previous patch.
>>
>> Is my spec interpretation here reasonable? i965 dies on this because it's trying
>> to memcpy from client memory near zero, which makes little sense in the core
>> profile.
>
> There are several variations of "undefined" in the GL spec.  One of them
> includes the possibility of program termination.  What does the spec
> actually say in this case?
>
>>  tests/all.py                          |  1 +
>>  tests/spec/gl-3.1/CMakeLists.gl.txt   |  1 +
>>  tests/spec/gl-3.1/vao-broken-attrib.c | 74 +++++++++++++++++++++++++++++++++++
>>  3 files changed, 76 insertions(+)
>>  create mode 100644 tests/spec/gl-3.1/vao-broken-attrib.c
>>
>> diff --git a/tests/all.py b/tests/all.py
>> index 31704aa..3c1e59d 100644
>> --- a/tests/all.py
>> +++ b/tests/all.py
>> @@ -946,6 +946,7 @@ gl31 = {}
>>  spec['!OpenGL 3.1'] = gl31
>>  gl31['draw-buffers-errors'] = concurrent_test('gl-3.1-draw-buffers-errors')
>>  gl31['genned-names'] = concurrent_test('gl-3.1-genned-names')
>> +gl31['vao-broken-attrib'] = concurrent_test('gl-3.1-vao-broken-attrib')
>>  gl31['minmax'] = concurrent_test('gl-3.1-minmax')
>>  for subtest in ['generated', 'written', 'flush']:
>>      cmdline = 'primitive-restart-xfb {0}'.format(subtest)
>> diff --git a/tests/spec/gl-3.1/CMakeLists.gl.txt b/tests/spec/gl-3.1/CMakeLists.gl.txt
>> index 7d835e8..2a7882d 100644
>> --- a/tests/spec/gl-3.1/CMakeLists.gl.txt
>> +++ b/tests/spec/gl-3.1/CMakeLists.gl.txt
>> @@ -13,5 +13,6 @@ piglit_add_executable (gl-3.1-draw-buffers-errors draw-buffers-errors.c)
>>  piglit_add_executable (gl-3.1-genned-names genned-names.c)
>>  piglit_add_executable (gl-3.1-minmax minmax.c)
>>  piglit_add_executable (gl-3.1-primitive-restart-xfb primitive-restart-xfb.c)
>> +piglit_add_executable (gl-3.1-vao-broken-attrib vao-broken-attrib.c)
>>
>>  # vim: ft=cmake:
>> diff --git a/tests/spec/gl-3.1/vao-broken-attrib.c b/tests/spec/gl-3.1/vao-broken-attrib.c
>> new file mode 100644
>> index 0000000..da17cc7
>> --- /dev/null
>> +++ b/tests/spec/gl-3.1/vao-broken-attrib.c
>> @@ -0,0 +1,74 @@
>> +/*
>> + * Copyright (c) 2014 Intel Corporation
>> + *
>> + * Permission is hereby granted, free of charge, to any person obtaining a
>> + * copy of this software and associated documentation files (the "Software"),
>> + * to deal in the Software without restriction, including without limitation
>> + * on the rights to use, copy, modify, merge, publish, distribute, sub
>> + * license, and/or sell copies of the Software, and to permit persons to whom
>> + * the Software is furnished to do so, subject to the following conditions:
>> + *
>> + * The above copyright notice and this permission notice (including the next
>> + * paragraph) shall be included in all copies or substantial portions of the
>> + * Software.
>> + *
>> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
>> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
>> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
>> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
>> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
>> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
>> + * DEALINGS IN THE SOFTWARE.
>> + */
>> +
>> +/**
>> + * @file vao-broken-attrib.c
>> + *
>> + * Tests that in the core profile, drawing with a vertex attrib enabled but not
>> + * sourced from a buffer does not crash the driver. Exercises a bug in i965.
>> + *
>> + * The GL 4.5 spec says:
>> + *   "If any enabled array’s buffer binding is zero when DrawArrays or
>> + *   one of the other drawing commands defined in section 10.4 is called,
>> + *   the result is undefined.""
>> + *
>> + * Note that this crash is reasonable (but unfortunate) in versions of GL which
>> + * permit vertex attributes to be sourced from client memory.
>> + */
>> +
>> +#include "piglit-util-gl.h"
>> +#include "piglit-matrix.h"
>> +
>> +PIGLIT_GL_TEST_CONFIG_BEGIN
>> +     config.supports_gl_core_version = 31;
>> +     config.window_visual = PIGLIT_GL_VISUAL_RGBA | PIGLIT_GL_VISUAL_DOUBLE;
>> +PIGLIT_GL_TEST_CONFIG_END
>> +
>> +
>> +enum piglit_result
>> +piglit_display(void)
>> +{
>> +     /* unreached */
>> +     return PIGLIT_FAIL;
>> +}
>> +
>> +void
>> +piglit_init(int argc, char **argv)
>> +{
>> +     GLuint vao;
>> +     GLuint prog = piglit_build_simple_program(
>> +                     "#version 130\n in vec4 x; void main() { gl_Position = x; }",
>> +                     "#version 130\n void main() { gl_FragColor = vec4(0); }");
>> +     glUseProgram(prog);
>> +
>> +     glGenVertexArrays(1, &vao);
>> +     glBindVertexArray(vao);
>> +
>> +     /* Enable this array but don't source it from anywhere. */
>> +     glEnableVertexAttribArray(0);
>> +
>> +     /* Result of this draw is undefined, but shouldn't crash! */
>> +     glDrawArrays(GL_TRIANGLES, 0, 3);
>> +
>> +     piglit_report_result(PIGLIT_PASS);
>> +}
>>
>