Re: [PATCH vkd3d v2 1/2] tests: Add test for texture placement at 64kb alignment.

[Henri Verbeet]

On Thu, 1 Jul 2021 at 14:37, Conor McCarthy  wrote:
> - for (i = 0; i < resource_desc.Width * resource_desc.Height; ++i)
> -
>    upload_buffer[i] = 0xdeadbeef;
> - texture_data.SlicePitch = texture_data.RowPitch * resource_desc.Height;
> - reset_command_list(command_list, context.allocator);
> - /* Write data to the first texture to check if the second is overwritten.
> -
> * Resource overlap may still go undetected depending on the actual layout
> -
> * used by the driver. */
> - upload_texture_data(textures[0], &texture_data, 1, queue, command_list);
> -
> - reset_command_list(command_list, context.allocator);
> - transition_resource_state(command_list, textures[1],
> -
>        D3D12_RESOURCE_STATE_COPY_DEST, D3D12_RESOURCE_STATE_COPY_SOURCE);
> - get_texture_readback_with_command_list(textures[1], 0, &rb, queue, command_list);
> - for (y = 0; y < resource_desc.Height; ++y)
> - {
> -
>    for (x = 0; x < resource_desc.Width; ++x)
> -
>    {
> -
>        i = get_readback_uint(&rb, x, y, 0);
> -
>        ok(i == 0xcafef00d, "Expected 0xcafef00d, got %#x at %u, %u.\n", i, x, y);
> -
>    }
> - }
> - release_resource_readback(&rb);
> -

We'll want to use check_sub_resource_uint() here.

Is this test missing a todo_if()? The returned alignment is 64 KiB
here on all my systems, so I can't test the actual issue, but
presumably the test is supposed to fail on setups that do require
larger alignments.

Or is this succeeding because we fall back to a separate allocation in
vkd3d_bind_heap_memory()? In that case though:
  - Why is that a problem for the actual application?
  - We may be able to detect that by aliasing multiple resources to
the same heap offset.