1 files changed, 37 insertions, 0 deletions
diff --git a/cli/tests/testdata/webgpu_computepass_shader.wgsl b/cli/tests/testdata/webgpu_computepass_shader.wgsl
new file mode 100644
index 000000000..7d4748e2a
--- /dev/null
+++ b/cli/tests/testdata/webgpu_computepass_shader.wgsl
@@ -0,0 +1,37 @@
+[[block]]
+struct PrimeIndices {
+    data: [[stride(4)]] array<u32>;
+}; // this is used as both input and output for convenience
+[[group(0), binding(0)]]
+var<storage> v_indices: [[access(read_write)]] PrimeIndices;
+// The Collatz Conjecture states that for any integer n:
+// If n is even, n = n/2
+// If n is odd, n = 3n+1
+// And repeat this process for each new n, you will always eventually reach 1.
+// Though the conjecture has not been proven, no counterexample has ever been found.
+// This function returns how many times this recurrence needs to be applied to reach 1.
+fn collatz_iterations(n_base: u32) -> u32{
+    var n: u32 = n_base;
+    var i: u32 = 0u;
+    loop {
+        if (n <= 1u) {
+            break;
+        }
+        if (n % 2u == 0u) {
+            n = n / 2u;
+        }
+        else {
+            // Overflow? (i.e. 3*n + 1 > 0xffffffffu?)
+            if (n >= 1431655765u) {   // 0x55555555u
+                return 4294967295u;   // 0xffffffffu
+            }
+            n = 3u * n + 1u;
+        }
+        i = i + 1u;
+    }
+    return i;
+}
+[[stage(compute), workgroup_size(1)]]
+fn main([[builtin(global_invocation_id)]] global_id: vec3<u32>) {
+    v_indices.data[global_id.x] = collatz_iterations(v_indices.data[global_id.x]);
+}