[MUSA][18/N] Add MUSA-optimized kernel implementations for hot ops (#23255)

Signed-off-by: Joey-gvwal <joey_gvwal@yeah.net>
Co-authored-by: R0CKSTAR <yeahdongcn@gmail.com>

sgl-kernel/include/musa/dispatch_utils.h

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2020-2026, Moore Threads Technology Co., Ltd("Moore Threads").
+ * All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Adapted from
+ * https://github.com/pytorch/pytorch/blob/v2.0.1/aten/src/ATen/Dispatch.h
+ */
+#pragma once
+
+#include <torch/all.h>
+
+#define MUSA_LDG(arg) __ldg(arg)
+
+#define MUSA_DISPATCH_CASE_FLOATING_TYPES(...)         \
+  AT_DISPATCH_CASE(at::ScalarType::Float, __VA_ARGS__) \
+  AT_DISPATCH_CASE(at::ScalarType::Half, __VA_ARGS__)  \
+  AT_DISPATCH_CASE(at::ScalarType::BFloat16, __VA_ARGS__)
+
+#define MUSA_DISPATCH_FLOATING_TYPES(TYPE, NAME, ...) \
+  AT_DISPATCH_SWITCH(TYPE, NAME, MUSA_DISPATCH_CASE_FLOATING_TYPES(__VA_ARGS__))