sycl: fuse RMS_NORM + MUL (#26015)

ggml/src/ggml-sycl/fusion.hpp

@@ -0,0 +1,15 @@
+#ifndef GGML_SYCL_FUSION_HPP
+#define GGML_SYCL_FUSION_HPP
+
+#include <initializer_list>
+
+#include "common.hpp"
+
+// Backend-side fusability test. `ops` names a candidate op sequence starting at cgraph node
+// `node_idx`; the result is true only if ggml considers that subgraph fusable *and* the SYCL
+// kernel which would service it accepts the tensors involved (types, shapes, contiguity).
+//
+// Lives in its own translation unit because it grows a branch per supported op sequence.
+bool ggml_sycl_can_fuse(const ggml_cgraph * cgraph, int node_idx, std::initializer_list<enum ggml_op> ops);
+
+#endif  // GGML_SYCL_FUSION_HPP