Bug 89722

Summary: [ILK Bisected]Ogles2conform/ES2-CTS.gtf.GL.equal.equal_vec2_frag fails
Product: Mesa Reporter: lu hua <huax.lu>
Component: Drivers/DRI/i965Assignee: Ian Romanick <idr>
Status: VERIFIED FIXED QA Contact: Intel 3D Bugs Mailing List <intel-3d-bugs>
Severity: normal    
Priority: medium    
Version: git   
Hardware: All   
OS: Linux (All)   
Whiteboard:
i915 platform: i915 features:

Description lu hua 2015-03-23 02:32:51 UTC 
System Environment:
--------------------------
Platform: ILK
Libdrm:		(master)libdrm-2.4.60-17-g8dff7a04780a0f028aa7c0218806a5ee59b1a40d
Mesa:		(master)7c7954b09dd28502aedb3eed312672620b9e6b7a
Xserver:	(master)xorg-server-1.17.0-23-g0a78b599b34cc8b5fe6fe82f90e90234e8ab7a56
Xf86_video_intel:(master)2.99.917-203-g44452825fb862c81957f53e04f739e2d96864f91
Libva:		(master)dbeeed0ec1b5eb192380fcdacfea86e0de1584af
Libva_intel_driver:(master)8ac2289aca552998d290bbc8bc2b44fbb510b1f9
Kernel:   (drm-intel-nightly)294a23a2fbb36c57ea89b5cfde94017c6a1124a2

Bug detailed description:
-------------------------
It fails on mesa master branch,works well on 10.5 branch. 
Following cases also fail:
ES2-CTS.gtf.GL.equal.equal_vec3_frag
ES2-CTS.gtf.GL.notEqual.notEqual_ivec2_frag
ES2-CTS.gtf.GL.notEqual.notEqual_ivec3_frag
ES2-CTS.gtf.GL.notEqual.notEqual_vec2_frag
ES2-CTS.gtf.GL.notEqual.notEqual_vec3_frag


Bisect shows:b616164c95cb495ce43f6b61dc805ed911a85e89 is the first bad commit
commit b616164c95cb495ce43f6b61dc805ed911a85e89
Author:     Ian Romanick <ian.d.romanick@intel.com>
AuthorDate: Fri Jan 23 17:31:12 2015 -0800
Commit:     Ian Romanick <ian.d.romanick@intel.com>
CommitDate: Thu Mar 19 10:21:08 2015 -0700

    i965/fs: Emit better b2f of an expression on GEN4 and GEN5

    On platforms that do not natively generate 0u and ~0u for Boolean
    results, b2f expressions that look like

        f = b2f(expr cmp 0)

    will generate better code by pretending the expression is

        f = ir_triop_sel(0.0, 1.0, expr cmp 0)

    This is because the last instruction of "expr" can generate the
    condition code for the "cmp 0".  This avoids having to do the "-(b & 1)"
    trick to generate 0u or ~0u for the Boolean result.  This means code like

        mov(16)         g16<1>F         1F
        mul.ge.f0(16)   null            g6<8,8,1>F      g14<8,8,1>F
        (+f0) sel(16)   m6<1>F          g16<8,8,1>F     0F

    will be generated instead of

        mul(16)         g2<1>F          g12<8,8,1>F     g4<8,8,1>F
        cmp.ge.f0(16)   g2<1>D          g4<8,8,1>F      0F
        and(16)         g4<1>D          g2<8,8,1>D      1D
        and(16)         m6<1>D          -g4<8,8,1>D     0x3f800000UD

    v2: When the comparison is either == 0.0 or != 0.0 use the knowledge
    that the true (or false) case already results in zero would allow better
    code generation by possibly avoiding a load-immediate instruction.

    v3: Apply the optimization even when neither comparitor is zero.

    Shader-db results:

    GM45 (0x2A42):
    total instructions in shared programs: 3551002 -> 3550829 (-0.00%)
    instructions in affected programs:     33269 -> 33096 (-0.52%)
    helped:                                121

    Iron Lake (0x0046):
    total instructions in shared programs: 4993327 -> 4993146 (-0.00%)
    instructions in affected programs:     34199 -> 34018 (-0.53%)
    helped:                                129

    No change on other platforms.


output:
dEQP Core GL-CTS-2.0 (0x0052484b) starting..
  target implementation = 'X11'

Test case 'ES2-CTS.gtf.GL.equal.equal_vec2_frag'..
#+ GTF/GL/equal/equal_vec2_frag.shader1.ppm and GTF/GL/equal/equal_vec2_frag.shader2.ppm are different
  Fail (Fail)

DONE!

Test run totals:
  Passed:        0/1 (0.00%)
  Failed:        1/1 (100.00%)
  Not supported: 0/1 (0.00%)
  Warnings:      0/1 (0.00%)

Reproduce steps:
----------------
1. start X
2. ./glcts --deqp-case=ES2-CTS.gtf.GL.equal.equal_vec2_frag
Comment 1 Ian Romanick 2015-03-23 21:02:39 UTC 
There is a patch on the mailing list that should fix this issue.  Please test.

http://lists.freedesktop.org/archives/mesa-dev/2015-March/080368.html
Comment 2 lu hua 2015-03-25 05:29:29 UTC 
(In reply to Ian Romanick from comment #1)
> There is a patch on the mailing list that should fix this issue.  Please
> test.
> 
> http://lists.freedesktop.org/archives/mesa-dev/2015-March/080368.html

Apply this patch ,it still fails.
output:
dEQP Core GL-CTS-2.0 (0x0052484b) starting..
  target implementation = 'X11'

Test case 'ES2-CTS.gtf.GL.equal.equal_vec2_frag'..
#+ GTF/GL/equal/equal_vec2_frag.shader1.ppm and GTF/GL/equal/equal_vec2_frag.shader2.ppm are different
  Fail (Fail)

DONE!

Test run totals:
  Passed:        0/1 (0.00%)
  Failed:        1/1 (100.00%)
  Not supported: 0/1 (0.00%)
  Warnings:      0/1 (0.00%)
Comment 3 Ian Romanick 2015-03-25 16:50:37 UTC 
Does just ES2-CTS.gtf.GL.equal.equal_vec3_frag fail?  What about the various notEqual tests from the original report?
Comment 4 Ian Romanick 2015-03-25 22:43:36 UTC 
Also... I sent two tests to the piglit list.  Could you try them on Iron Lake with and without the Mesa patch?

http://patchwork.freedesktop.org/patch/45477/
http://patchwork.freedesktop.org/patch/45480/

I don't have very easy access to an Iron Lake system right now, so I had to try reproducing the bug on a different system.  I was able to get these tests to fail on Ivy Bridge without the patch, and they both pass with the patch.

Thanks.
Comment 5 lu hua 2015-03-26 07:33:11 UTC 
On ILK: Without the patch, both 2 cases fail.With the patch, fs-notEqual-of-expression.shader_test works well. fs-equal-of-expression.shader_test still fails.
On IVB, these 2 cases always pass without/with patch.

With patch output:
[root@x-pk5 piglit]# bin/shader_runner /GFX/Test/Piglit/piglit/tests/spec/glsl-1.10/execution/fs-notEqual-of-expression.shader_test -auto
PIGLIT: {"result": "pass" }
[root@x-pk5 piglit]# bin/shader_runner /GFX/Test/Piglit/piglit/tests/spec/glsl-1.10/execution/fs-equal-of-expression.shader_test -auto
Probe color at (0,0)
  Expected: 0.000000 1.000000 0.000000 1.000000
  Observed: 0.000000 1.000000 1.000000 1.000000
PIGLIT: {"result": "fail" }

Without patch output:
[root@x-pk5 piglit]# bin/shader_runner /GFX/Test/Piglit/piglit/tests/spec/glsl-1.10/execution/fs-equal-of-expression.shader_test -auto
Probe color at (0,0)
  Expected: 0.000000 1.000000 0.000000 1.000000
  Observed: 0.000000 1.000000 1.000000 1.000000
PIGLIT: {"result": "fail" }
[root@x-pk5 piglit]# bin/shader_runner /GFX/Test/Piglit/piglit/tests/spec/glsl-1.10/execution/fs-notEqual-of-expression.shader_test -auto
Probe color at (0,0)
  Expected: 0.000000 1.000000 0.000000 1.000000
  Observed: 0.000000 1.000000 1.000000 1.000000
PIGLIT: {"result": "fail" }
Comment 6 Ian Romanick 2015-04-07 19:42:08 UTC 
Updated patch:

http://lists.freedesktop.org/archives/mesa-dev/2015-April/081416.html

Please test.  Thanks.
Comment 7 lu hua 2015-04-08 07:54:49 UTC 
(In reply to Ian Romanick from comment #6)
> Updated patch:
> 
> http://lists.freedesktop.org/archives/mesa-dev/2015-April/081416.html
> 
> Please test.  Thanks.

Fixed by this patch.
Comment 8 lu hua 2015-05-12 05:45:02 UTC 
Verified.Fixed.

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.