Created attachment 97655 [details]
output

System Environment:
--------------------------
Platform: Ivybridge
Libdrm:		(master)libdrm-2.4.53-6-gd4083dc762a2974c35ecd16be995272bbb6d57b4
Mesa:		(master)ba6dcb3c2b8f516b120f591144bf6c3751f0e3f9
Xserver:	(master)xorg-server-1.15.99.902-20-gc7011249d2abe6cc7af82ee4b79d8f6873444707
Xf86_video_intel:(master)2.99.911-89-g08e71e1820d6fcb6829b4ebd360beadc1f250295
Libva:		(staging)5e10a246287fa2dd3fae2bf756a5b33087cc097c
Libva_intel_driver:(staging)782b8afdda14f000874d8acf51c3e8c490d55773
Kernel:	(drm-intel-nightly)1e771b84e47085ef9b6efea1321e7cb5a8b2c06

Bug detailed description:
-----------------------------
It fails on Ivybridge and Haswell platforms with mesa master branch, and works well on 10.1 branch.
Bisect shows:5ff1e446d44bb9d50f84883c7058635cb070e069 is the first bad commit
commit 5ff1e446d44bb9d50f84883c7058635cb070e069
Author:     Matt Turner <mattst88@gmail.com>
AuthorDate: Wed Apr 9 14:31:10 2014 -0700
Commit:     Matt Turner <mattst88@gmail.com>
CommitDate: Fri Apr 18 09:16:19 2014 -0700

    i965/fs: Simplify interference scan in register coalescing.

    We were starting at the beginning of the instruction list, rather than
    with the MOV instruction itself. This allows us to coalesce after
    control flow.

    Excluding the shaders from an unreleased title, the shader-db results:

    total instructions in shared programs: 1603791 -> 1594215 (-0.60%)
    instructions in affected programs:     678772 -> 669196 (-1.41%)
    GAINED:                                5
    LOST:                                  0

    Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

Reproduce steps:
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1. xinit
2. ./GTF -width=64 -height=64 -run=GL3Tests/shadow/shadow_execution_frag.test