1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
/*
* 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
|
