[Kernel] Update cutlass_scaled_mm to support 2d group (blockwise) scaling (#11868)

csrc/core/math.hpp

@@ -1,7 +1,14 @@
+#pragma once
+
 #include <climits>
 #include <iostream>
 
-inline uint32_t next_pow_2(uint32_t const num) {
+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 T>
+inline constexpr std::enable_if_t<std::is_integral_v<T>, T> ceil_div(T a, T b) {
+  return (a + b - 1) / b;
 }