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

[Ian Romanick]

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);
> +}
>