#pragma once
#include <c10/macros/Macros.h>
#include <type_traits>
// Utility to guarantee complete unrolling of a loop where the bounds are known
// at compile time. Various pragmas achieve similar effects, but are not as
// portable across compilers.
// Example: c10::ForcedUnroll<4>{}(f); is equivalent to f(0); f(1); f(2); f(3);
namespace c10 {
template <int n>
struct ForcedUnroll {
template <typename Func, typename... Args>
C10_ALWAYS_INLINE void operator()(const Func& f, Args... args) const {
ForcedUnroll<n - 1>{}(f, args...);
f(std::integral_constant<int, n - 1>{}, args...);
}
};
template <>
struct ForcedUnroll<1> {
template <typename Func, typename... Args>
C10_ALWAYS_INLINE void operator()(const Func& f, Args... args) const {
f(std::integral_constant<int, 0>{}, args...);
}
};
} // namespace c10