NVFP4-1.1: ultra-minimal test — Float32 comparison + Int32 select

tests/unit/test_ultra_minimal.py

@@ -0,0 +1,31 @@
+"""Ultra-minimal test: Float32 comparison + Int32 assignment in CuTeDSL."""
+import torch
+import cutlass
+import cutlass.cute as cute
+import cutlass.torch as cutlass_torch
+
+
+@cute.kernel
+def ultra_minimal_kernel(
+    input_f32: cute.Tensor,
+    output_i32: cute.Tensor,
+):
+    tidx, _, _ = cute.arch.thread_idx()
+    if tidx == cutlass.Int32(0):
+        x = cutlass.Float32(3.7)  # no load, just a constant
+        r = cutlass.Int32(0)
+        if x > cutlass.Float32(2.0):
+            r = cutlass.Int32(1)
+        cute.arch.store(output_i32.iterator, r)
+
+
+if __name__ == "__main__":
+    out = torch.zeros(1, dtype=torch.int32, device='cuda')
+    dummy = torch.zeros(1, dtype=torch.float32, device='cuda')
+    dc = cutlass_torch.from_dlpack(dummy).mark_layout_dynamic(leading_dim=0)
+    oc = cutlass_torch.from_dlpack(out).mark_layout_dynamic(leading_dim=0)
+    print("Compiling...")
+    compiled = cute.compile(ultra_minimal_kernel, dc, oc)
+    print("Running...")
+    compiled(dc, oc)
+    print(f'Result: {out.item()} (expected 1)')