From 29081c671f65b8ab0a1ec50dda47f58f2faf2468 Mon Sep 17 00:00:00 2001
From: Danylo Piliaiev <danylo.piliaiev@globallogic.com>
Date: Fri, 22 Nov 2019 18:05:14 +0200
Subject: [PATCH] drirc: Add glsl_zero_init workaround for GpuTest
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GiMark benchmark from GpuTest has such code in VS:

 out vec4 lightDir0;
 out vec4 lightDir1;

 ...

 lightDir0.xyz = lp0 - vVertex.xyz;
 lightDir1.xyz = lp1 - vVertex.xyz;

In FS:

 float distSqr = dot(lightDir0, lightDir0);

So due to the usage of uninitialized .w channel in the dot product,
distSqr may become undefined which results in many black dots
in the test on Iris.

In https://www.geeks3d.com/forums/index.php/topic,6242.0.html
developer stated that this benchmark most likely won't be updated.

Closes: https://gitlab.freedesktop.org/mesa/mesa/issues/1919
Signed-off-by: Danylo Piliaiev <danylo.piliaiev@globallogic.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
---
 src/util/00-mesa-defaults.conf | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/util/00-mesa-defaults.conf b/src/util/00-mesa-defaults.conf
index ba343ec5ffb..734161650b7 100644
--- a/src/util/00-mesa-defaults.conf
+++ b/src/util/00-mesa-defaults.conf
@@ -243,6 +243,13 @@ TODO: document the other workarounds.
             <option name="force_compat_profile" value="true" />
         </application>
 
+        <application name="GpuTest" executable="GpuTest">
+            <!-- GiMark benchmark from GpuTest does not initialize .w channel of
+                 lightDir0 and lightDir1 varyings in the vertex shader while
+                 uses it in the fragment shader. -->
+            <option name="glsl_zero_init" value="true"/>
+        </application>
+
         <!-- The GL thread whitelist is below, workarounds are above.
              Keep it that way. -->
 
-- 
2.30.2