topic Re: Regression between driver versions 3907 and 3960 (Intel HD 4600) in Graphics

Regression between driver versions 3907 and 3960 (Intel HD 4600)

FC1 — Mon, 10 Nov 2014 11:39:34 GMT

Hi,

We have an application that does some intensive OpenGL 4.2 work (lots of image load/store and atomic counter stuff).

We noticed there is a regression between versions 3907 and 3960: one of our shaders no longer runs as expected.

Additionally, we have some issues with Intel GPUs in general. We found a compiler bug and one of our shaders still doesn't run at all on intel platforms (regardless of driver version). The same shader works fine on nVidia and AMD platforms.

Is it possible to get in touch with somebody at Intel in order to investigate these issues?

Thanks,

-FC

Re: Regression between driver versions 3907 and 3960 (Intel HD 4600)

Silvia_L_Intel1 — Tue, 11 Nov 2014 19:40:56 GMT

Fredice,

Could you please attach the DX Ddiag report for your system so I can report all the information on the engineers?

(Start -> Run -> dxdiag -> Save All Information).

Thanks

Re: Regression between driver versions 3907 and 3960 (Intel HD 4600)

FC1 — Wed, 12 Nov 2014 08:46:49 GMT

Hi Sylvia,

Below you will find the report generated by Dxdiag.

Regarding the shader that does not work at all regardless of the driver version being in use, I have two problems:

- my shader cannot be compiled as-is. A "syntax error syntax error" error occurs (yes, you read well: I get twice the message "syntax error", on the same line, separated by a single white space).

- to work around this issue, if I get rid of 1 pair of brackets at that location in my code (after having made sure it is safe to do so of course), compilation goes fine. Shader execution still is incorrect though.

Re: Regression between driver versions 3907 and 3960 (Intel HD 4600)

ROBERT_U_Intel — Wed, 12 Nov 2014 20:49:18 GMT

Hi Fredice

Could you confirm the issue also occurs on the lasts HD 4600 (Haswell) driver? It is available here: https://downloadcenter.intel.com/Detail_Desc.aspx?DwnldID=24348&lang=eng&ProdId=3719 Intel® Download Center

Thanks

Robert

Re: Regression between driver versions 3907 and 3960 (Intel HD 4600)

FC1 — Wed, 12 Nov 2014 21:17:12 GMT

Hi Robert,

Yes, I confirm there are 2 problems with this driver version (3960), which is the latest driver :

- one of our shaders is no longer running. This particular shader worked with the previous version (3907).

- we still have 1 shader that we don't manage to run on Intel hardware. On AMD and nVidia hardware, it runs fine. With this shader, we have a "syntax error syntax error" error when compiling. If we carefully adjust the code (removing one pair of parenthesis is actually enough for compilation to work), the shader compiles fine (and still runs fine on AMD and nVidia hardware) but does not work on Intel hardware.

Fred

nb: I can be contacted at frederic.cZZZx at inria dot fr. Replace 'ZZZ' with 'lau'.

If needed I could send to you a binary release that reproduces the GLSL issue.

Re: Regression between driver versions 3907 and 3960 (Intel HD 4600)

FC1 — Mon, 17 Nov 2014 10:33:38 GMT

Sylvia / Robert,

Is there an email address I can contact you to?

Thank you.

Re: Regression between driver versions 3907 and 3960 (Intel HD 4600)

ROBERT_U_Intel — Mon, 24 Nov 2014 17:26:04 GMT

Hi Fredice

Could you please provide a sample of the shaders you are using?

Thanks

Robert

Re: Regression between driver versions 3907 and 3960 (Intel HD 4600)

FC1 — Mon, 24 Nov 2014 17:43:11 GMT

Hi Robert,

I can provide a binary code to you that exhibits the issue.

If you contact me by email, I may be able to provide some shader source code.

Fred