diff --git a/util/test/demos/vk/vk_subgroup_zoo.cpp b/util/test/demos/vk/vk_subgroup_zoo.cpp
index bb32dffbd..c4c373766 100644
--- a/util/test/demos/vk/vk_subgroup_zoo.cpp
+++ b/util/test/demos/vk/vk_subgroup_zoo.cpp
@@ -258,6 +258,14 @@ void main()
     }
     data.x = subgroupAdd(id);
   }
+  else if(IsTest(8))
+  {
+     // Loops with different number of iterations per thread
+    for (uint i = 0; i < id; i++)
+    {
+      data.x += subgroupAdd(id);
+    }
+  }
   SetOuput(data);
 }