[NVIDIA] Support nvfp4 cutlass gemm (#13571)

csrc/torch_bindings.cpp

@@ -302,6 +302,13 @@ TORCH_LIBRARY_EXPAND(TORCH_EXTENSION_NAME, ops) {
       "SymInt size_k) -> Tensor");
   // conditionally compiled so impl registration is in source file
 
+  // CUTLASS nvfp4 block scaled GEMM
+  ops.def(
+      "cutlass_scaled_fp4_mm(Tensor! out, Tensor a, Tensor b,"
+      "                      Tensor block_scale_a, Tensor block_scale_b,"
+      "                      Tensor alpha) -> ()");
+  ops.impl("cutlass_scaled_fp4_mm", torch::kCUDA, &cutlass_scaled_fp4_mm);
+
   // CUTLASS w8a8 GEMM, supporting symmetric per-tensor or per-row/column
   // quantization, as well as bias
   ops.def(