Bug 76616 - [i965 Bisected]Piglit/spec/ARB_vertex_program/vp-sge-alias fails
Summary: [i965 Bisected]Piglit/spec/ARB_vertex_program/vp-sge-alias fails
Alias: None
Product: Mesa
Classification: Unclassified
Component: Drivers/DRI/i965 (show other bugs)
Version: unspecified
Hardware: All Linux (All)
: high major
Assignee: Matt Turner
QA Contact: Intel 3D Bugs Mailing List
Depends on:
Reported: 2014-03-26 06:12 UTC by lu hua
Modified: 2014-04-08 06:05 UTC (History)
2 users (show)

See Also:
i915 platform:
i915 features:


Description lu hua 2014-03-26 06:12:15 UTC
System Environment:
Platform: Ironlake
Libdrm:		(master)libdrm-2.4.52-10-g1cb5fc706cf5913d9dee33c939f65a23ecea17a5
Mesa:		(master)7683fce8781ef0169333c5ee1276392d058cfaa8
Xserver:	(master)xorg-server-
Cairo:		(master)bb17403622e9ea474017e0039af8ee48b2b285db
Libva:		(staging)bf2e1773d4373619232c4c653b8cda19ea329441
Kernel:	(drm-intel-nightly)84295583b8322f96a187c4fc5cca5dd7d511f57e

Bug detailed description:
It fails on Ironlake, Sandybridge, Ivybridge, Haswell, Baytrail and broadwell with mesa master branch.It doesn't happen on mesa 10.1 branch.

Bisect shows:9cd51bb0c4608258199c69bc7738e72f055799d2 is the first bad commit.
commit 9cd51bb0c4608258199c69bc7738e72f055799d2
Author:     Matt Turner <mattst88@gmail.com>
AuthorDate: Tue Mar 11 13:16:37 2014 -0700
Commit:     Matt Turner <mattst88@gmail.com>
CommitDate: Mon Mar 24 11:06:26 2014 -0700

    i965/vec4: Eliminate writes that are never read.

    With an awful O(n^2) algorithm that searches previous instructions for
    dead writes.

    total instructions in shared programs: 805582 -> 788074 (-2.17%)
    instructions in affected programs:     144561 -> 127053 (-12.11%)

    Reviewed-by: Eric Anholt <eric@anholt.net>

Probe color at (75,75)
  Expected: 1.000000 0.000000 1.000000 1.000000
  Observed: 0.000000 0.000000 1.000000 1.000000
Test /GFX/Test/Piglit/piglit/tests/shaders/generic/vp-sge-alias.vpfp:16 failed
PIGLIT: {'result': 'fail' }

Reproduce steps:
1. xinit
2. ./bin/vpfp-generic /GFX/Test/Piglit/piglit/tests/shaders/generic/vp-sge-alias.vpfp -fbo -auto
Comment 1 Matt Turner 2014-03-29 22:14:27 UTC
Thanks for the report. I've sent a patch. http://lists.freedesktop.org/archives/mesa-dev/2014-March/056832.html
Comment 2 lu hua 2014-03-31 05:45:20 UTC
(In reply to comment #1)
> Thanks for the report. I've sent a patch.
> http://lists.freedesktop.org/archives/mesa-dev/2014-March/056832.html

Fixed by this patch.
Comment 4 lu hua 2014-04-08 06:05:15 UTC

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