| /* |
| * Created by Joachim on 16/04/2019. |
| * Adapted from donated nonius code. |
| * |
| * Distributed under the Boost Software License, Version 1.0. (See accompanying |
| * file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| */ |
| |
| // Hinting the optimizer |
| |
| #ifndef TWOBLUECUBES_CATCH_OPTIMIZER_HPP_INCLUDED |
| #define TWOBLUECUBES_CATCH_OPTIMIZER_HPP_INCLUDED |
| |
| #if defined(_MSC_VER) |
| # include <atomic> // atomic_thread_fence |
| #endif |
| |
| namespace Catch { |
| namespace Benchmark { |
| #if defined(__GNUC__) || defined(__clang__) |
| template <typename T> |
| inline void keep_memory(T* p) { |
| asm volatile("" : : "g"(p) : "memory"); |
| } |
| inline void keep_memory() { |
| asm volatile("" : : : "memory"); |
| } |
| |
| namespace Detail { |
| inline void optimizer_barrier() { keep_memory(); } |
| } // namespace Detail |
| #elif defined(_MSC_VER) |
| |
| #pragma optimize("", off) |
| template <typename T> |
| inline void keep_memory(T* p) { |
| // thanks @milleniumbug |
| *reinterpret_cast<char volatile*>(p) = *reinterpret_cast<char const volatile*>(p); |
| } |
| // TODO equivalent keep_memory() |
| #pragma optimize("", on) |
| |
| namespace Detail { |
| inline void optimizer_barrier() { |
| std::atomic_thread_fence(std::memory_order_seq_cst); |
| } |
| } // namespace Detail |
| |
| #endif |
| |
| template <typename T> |
| inline void deoptimize_value(T&& x) { |
| keep_memory(&x); |
| } |
| |
| template <typename Fn, typename... Args> |
| inline auto invoke_deoptimized(Fn&& fn, Args&&... args) -> typename std::enable_if<!std::is_same<void, decltype(fn(args...))>::value>::type { |
| deoptimize_value(std::forward<Fn>(fn) (std::forward<Args...>(args...))); |
| } |
| |
| template <typename Fn, typename... Args> |
| inline auto invoke_deoptimized(Fn&& fn, Args&&... args) -> typename std::enable_if<std::is_same<void, decltype(fn(args...))>::value>::type { |
| std::forward<Fn>(fn) (std::forward<Args...>(args...)); |
| } |
| } // namespace Benchmark |
| } // namespace Catch |
| |
| #endif // TWOBLUECUBES_CATCH_OPTIMIZER_HPP_INCLUDED |