glsl-1.10: add simple loop unrolling test with loop counter in vec4

This tests whether the loop will unroll if one component of vec4 is
used as a loop counter. Similar code can be produced by running C&C3
Tiberium Wars under nine with non-integer hardware and than going
through ttn.

Signed-off-by: Pavel Ondračka <pavel.ondracka@gmail.com>
Reviewed-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/piglit/-/merge_requests/673>

1 files changed, 20 insertions, 0 deletions

diff --git a/tests/spec/glsl-1.10/execution/loops/glsl-fs-loop-vec4-counter.shader_test b/tests/spec/glsl-1.10/execution/loops/glsl-fs-loop-vec4-counter.shader_test
new file mode 100644
index 000000000..edb2a80cd
--- /dev/null
+++ b/tests/spec/glsl-1.10/execution/loops/glsl-fs-loop-vec4-counter.shader_test
@@ -0,0 +1,20 @@
+[require]
+GLSL >= 1.10
+
+[vertex shader passthrough]
+
+[fragment shader]
+vec4 color;
+void main()
+{
+   color = vec4(0.0, 0.0, 0.0, 0.0);
+   while (color.y < 0.5)
+   {
+      color.y = color.y + 1.0;
+   }
+   gl_FragColor = color;
+}
+
+[test]
+draw rect -1 -1 2 2
+probe rgba 1 1 0.0 1.0 0.0 0.0