369 - Did you know that C++17 added Hardware interference size?

README.md

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 > C++17
 
+* [Did you know that C++17 added Hardware interference size?](https://github.com/tip-of-the-week/cpp/blob/master/tips/369.md)
 * [Did you know that the underlying visit implementation of std::visit has changed since GCC12+, Clang15+?](https://github.com/tip-of-the-week/cpp/blob/master/tips/353.md)
 * [Did you know that run-time dispatching over type-list can be implemented many different ways?](https://github.com/tip-of-the-week/cpp/blob/master/tips/337.md)
 * [Did you know that you can simplify `boost.mp11` API with DSL?](https://github.com/tip-of-the-week/cpp/blob/master/tips/335.md)

tips/369.md

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+<details open><summary>Info</summary><p>
+
+* **Did you know that C++17 added Hardware interference size?**
+
+ * https://wg21.link/P0154
+
+</p></details><details open><summary>Example</summary><p>
+
+```cpp
+#include <new>
+static_assert(64u == std::hardware_destructive_interference_size); // x86-64
+```
+
+> https://godbolt.org/z/haPq9583q
+
+</p></details><details open><summary>Puzzle</summary><p>
+
+* **Can you implement `cache_aligned_array` function which returns cache size aligned std::array with provided values?
+
+```cpp
+constexpr auto cache_aligned_array(auto... args) {
+ // TODO
+ return std::array{args...};
+};
+
+static_assert(std::hardware_destructive_interference_size == alignof(cache_aligned_array(1, 2, 3)));
+```
+
+> https://godbolt.org/z/EvKco4fG7
+
+</p></details>
+
+</p></details><details><summary>Solutions</summary><p>
+
+```cpp
+constexpr auto cache_aligned_array(auto... args) {
+ struct alignas(std::hardware_destructive_interference_size) 
+ : decltype(std::array{args...}) { } array {args...};
+ return array;
+};
+
+static_assert(std::hardware_destructive_interference_size == alignof(cache_aligned_array(1, 2, 3)));
+```
+
+> https://godbolt.org/z/oTezYjsW4
+
+</p></details>