[Mesa-dev] [PATCH 2/2] Remove fs-discard-exit-3

[Marek Olšák]

From: Marek Olšák <marek.olsak at amd.com>

The test is wrong and the GLSL 1.30 citation in the test states very
clearly that discard can cause non-uniform control flow for any code that
follows.
---
 .../execution/fs-discard-exit-3.shader_test        | 76 ----------------------
 1 file changed, 76 deletions(-)
 delete mode 100644 tests/spec/glsl-1.30/execution/fs-discard-exit-3.shader_test

diff --git a/tests/spec/glsl-1.30/execution/fs-discard-exit-3.shader_test b/tests/spec/glsl-1.30/execution/fs-discard-exit-3.shader_test
deleted file mode 100644
index 14e9b47..0000000
--- a/tests/spec/glsl-1.30/execution/fs-discard-exit-3.shader_test
+++ /dev/null
@@ -1,76 +0,0 @@
-# This is a test for derivatives behavior after a discard.
-#
-# From the GLSL 1.30 spec:
-#
-#     "The discard keyword is only allowed within fragment shaders. It
-#      can be used within a fragment shader to abandon the operation
-#      on the current fragment. This keyword causes the fragment to be
-#      discarded and no updates to any buffers will occur. Control
-#      flow exits the shader, and subsequent implicit or explicit
-#      derivatives are undefined when this control flow is non-uniform
-#      (meaning different fragments within the primitive take
-#      different control paths)."
-
-
-[require]
-GLSL >= 1.30
-
-[vertex shader]
-#version 130
-
-in vec4 vertex;
-out vec2 texcoords;
-void main()
-{
-	gl_Position = vertex;
-
-	/* Turn the texcoords into a 1:1 mapping with pixels when
-	 * interpolated.  This means that the coords for our 2x2
-	 * subspan we're interested in for the FS will be:
-	 *
-	 * +-----+-----+
-	 * | 0,1 | 1,1 |
-	 * +-----+-----+
-	 * | 0,0 | 0,1 |
-	 * +-----+-----+
-	 *
-	 * So it would sample the 1x1 miplevel of the GL_TEXTURE_2D
-	 * miptree, unless some other math occurs...
-	 */
-	texcoords.yx = (vertex.xy + 1) / 2 * 250;
-}
-
-[fragment shader]
-#version 130
-in vec2 texcoords;
-uniform sampler2D s;
-
-void main()
-{
-	if (gl_FragCoord.x >= 1.0 || gl_FragCoord.y >= 1.0)
-		discard;
-
-	/* Now, we have uniform control after the discard (well,
-	 * except for the join after the if statement up there).  The
-	 * derivatives on this sample should get us the same values
-	 * for the undiscarded pixel as if we hadn't done any discard
-	 * (comment out the "discard" above to see).
-	 */
-	gl_FragColor = texture(s, texcoords / 4);
-}
-
-[vertex data]
-vertex/float/2
--1.0 -1.0
- 1.0 -1.0
- 1.0  1.0
--1.0  1.0
-
-[test]
-clear color 0.5 0.5 0.5 0.5
-clear
-
-texture miptree 0
-
-draw arrays GL_TRIANGLE_FAN 0 4
-probe rgba 0 0 0.0 1.0 0.0 1.0
-- 
2.5.0