[Perf] Tunings for SM100 FP8 CUTLASS kernel (#8818)

sgl-kernel/csrc/gemm/math.hpp

@@ -0,0 +1,28 @@
+#pragma once
+
+#include <climits>
+#include <iostream>
+
+inline constexpr uint32_t next_pow_2(uint32_t const num) {
+  if (num <= 1) return num;
+  return 1 << (CHAR_BIT * sizeof(num) - __builtin_clz(num - 1));
+}
+
+template <typename A, typename B>
+static inline constexpr auto div_ceil(A a, B b) {
+  return (a + b - 1) / b;
+}
+
+// Round a down to the next multiple of b. The caller is responsible for making
+// sure that b is non-zero
+template <typename T>
+inline constexpr T round_to_previous_multiple_of(T a, T b) {
+  return a % b == 0 ? a : (a / b) * b;
+}
+
+// Round a up to the next multiple of b. The caller is responsible for making
+// sure that b is non-zero
+template <typename T>
+inline constexpr T round_to_next_multiple_of(T a, T b) {
+  return a % b == 0 ? a : ((a / b) + 1) * b;
+}