[ox/std] Add and integrate std::launder

deps/ox/src/ox/std/new.hpp

@@ -30,11 +30,49 @@ constexpr void *operator new(std::size_t, void *addr) noexcept {
 constexpr void *operator new[](std::size_t, void *addr) noexcept {
 	return addr;
 }
+
+namespace std {
+
+template<typename T>
+[[nodiscard]]
+constexpr T* launder(T* __p) noexcept {
+	return __builtin_launder(__p);
+}
+
+template<typename T, typename... Args, bool noex>
+void launder(T(*)(Args...) noexcept(noex)) = delete;
+template<typename T, typename... Args, bool noex>
+void launder(T(*)(Args......) noexcept(noex)) = delete;
+void launder(void*) = delete;
+void launder(void const*) = delete;
+void launder(volatile void*) = delete;
+void launder(volatile void const*) = delete;
+
+}
 #endif
 
 
 namespace ox {
 
+/**
+ * Aliases type T in size and alignment to allow allocating space for a T
+ * without running the constructor.
+ */
+template<typename T, std::size_t sz = sizeof(T)>
+struct alignas(alignof(T)) AllocAlias {
+	char buff[sz];
+	constexpr AllocAlias() noexcept = default;
+	[[nodiscard]]
+	auto data() noexcept {
+		return reinterpret_cast<T*>(this);
+	}
+	[[nodiscard]]
+	auto data() const noexcept {
+		return reinterpret_cast<T const*>(this);
+	}
+};
+
+
 template<typename T, typename U = T, typename ...Args>
 [[nodiscard]]
 constexpr U *make(Args &&...args) noexcept {

deps/ox/src/ox/std/types.hpp

@@ -63,25 +63,6 @@ namespace ox {
 
 using CString = char const*;
 
-/**
- * Aliases type T in size and alignment to allow allocating space for a T
- * without running the constructor.
- */
-template<typename T, std::size_t sz = sizeof(T)>
-struct alignas(alignof(T)) AllocAlias {
-	char buff[sz];
-	constexpr AllocAlias() noexcept = default;
-	[[nodiscard]]
-	auto data() noexcept {
-		return reinterpret_cast<T*>(this);
-	}
-	[[nodiscard]]
-	auto data() const noexcept {
-		return reinterpret_cast<const T*>(this);
-	}
-};
-
-
 template<std::size_t sz>
 struct SignedType {
 };

deps/ox/src/ox/std/vector.hpp

@@ -34,10 +34,10 @@ struct VectorAllocator {
 		ox::Array<AllocAlias<T>, Size> m_data = {};
 	protected:
 		constexpr VectorAllocator() noexcept = default;
-		constexpr VectorAllocator(const VectorAllocator&) noexcept = default;
+		constexpr VectorAllocator(VectorAllocator const&) noexcept = default;
 		constexpr VectorAllocator(VectorAllocator&&) noexcept = default;
 
-		constexpr void allocate(T **items, std::size_t cap) noexcept {
+		constexpr void allocate(T **items, std::size_t const cap) noexcept {
 			// small vector optimization cannot be done it constexpr, but it doesn't really matter in constexpr
 			if (std::is_constant_evaluated() || cap > Size) {
 				*items = Allocator{}.allocate(cap);
@@ -49,42 +49,26 @@ struct VectorAllocator {
 		constexpr void moveConstructItemsFrom(
 				T **items,
 				VectorAllocator *src,
-				const std::size_t count,
+				std::size_t const count,
-				const std::size_t cap) noexcept {
+				std::size_t const cap) noexcept {
 			// this totally idiotic redundant check (&& count <= Size) is required to address a bug in devkitARM,
 			// try removing it later
 			if (!std::is_constant_evaluated()) {
 				if (cap <= m_data.size() && count <= m_data.size()) {
 					for (auto i = 0u; i < count; ++i) {
-						const auto dstItem = reinterpret_cast<T *>(&m_data[i]);
+						auto const srcItem = std::launder(reinterpret_cast<T*>(&src->m_data[i]));
-						const auto srcItem = reinterpret_cast<T *>(&src->m_data[i]);
+						new (&m_data[i]) T(std::move(*srcItem));
-						std::construct_at<T>(dstItem, std::move(*srcItem));
+					}
+					if (count) {
+						*items = std::launder(reinterpret_cast<T*>(m_data.data()));
+					} else {
+						*items = reinterpret_cast<T*>(m_data.data());
 					}
-					*items = reinterpret_cast<T*>(m_data.data());
 				}
 			}
 		}
 
-		constexpr void moveItemsFrom(
+		constexpr void deallocate(T *const items, std::size_t const cap) noexcept {
-				T **items,
-				VectorAllocator *src,
-				const std::size_t count,
-				const std::size_t cap) noexcept {
-			// this totally idiotic redundant check (&& count <= Size) is required to address a bug in devkitARM,
-			// try removing it later
-			if (!std::is_constant_evaluated()) {
-				if (cap <= m_data.size() && count <= m_data.size()) {
-					for (std::size_t i = 0; i < count; ++i) {
-						const auto dstItem = reinterpret_cast<T *>(&m_data[i]);
-						const auto srcItem = reinterpret_cast<T *>(&src->m_data[i]);
-						*dstItem = std::move(*srcItem);
-					}
-					*items = reinterpret_cast<T*>(m_data.data());
-				}
-			}
-		}
-
-		constexpr void deallocate(T *items, std::size_t cap) noexcept {
 			// small vector optimization cannot be done it constexpr, but it doesn't really matter in constexpr
 			if (std::is_constant_evaluated()) {
 				if (items) {
@@ -103,10 +87,10 @@ template<typename T, typename Allocator>
 struct VectorAllocator<T, Allocator, 0> {
 	protected:
 		constexpr VectorAllocator() noexcept = default;
-		constexpr VectorAllocator(const VectorAllocator&) noexcept = default;
+		constexpr VectorAllocator(VectorAllocator const&) noexcept = default;
 		constexpr VectorAllocator(VectorAllocator&&) noexcept = default;
 
-		constexpr void allocate(T **items, std::size_t cap) noexcept {
+		constexpr void allocate(T **items, std::size_t const cap) noexcept {
 			*items = Allocator{}.allocate(cap);
 		}
 
@@ -114,15 +98,15 @@ struct VectorAllocator<T, Allocator, 0> {
 		constexpr void moveConstructItemsFrom(
 				T**,
 				VectorAllocator*,
-				const std::size_t,
+				std::size_t const,
-				const std::size_t) noexcept {
+				std::size_t const) noexcept {
 		}
 
 		[[maybe_unused]]
-		constexpr void moveItemsFrom(T**, VectorAllocator*, const std::size_t, const std::size_t) noexcept {
+		constexpr void moveItemsFrom(T**, VectorAllocator*, std::size_t const, std::size_t const) noexcept {
 		}
 
-		constexpr void deallocate(T *items, std::size_t cap) noexcept {
+		constexpr void deallocate(T *const items, std::size_t const cap) noexcept {
 			if (items) {
 				Allocator{}.deallocate(items, cap);
 			}
@@ -421,7 +405,7 @@ constexpr Vector<T, SmallVectorSize, Allocator> &Vector<T, SmallVectorSize, Allo
 		m_size = other.m_size;
 		m_cap = other.m_cap;
 		m_items = other.m_items;
-		this->moveItemsFrom(&m_items, &other, m_size, m_cap);
+		this->moveConstructItemsFrom(&m_items, &other, m_size, m_cap);
 		other.m_size = 0;
 		other.m_cap = 0;
 		other.m_items = nullptr;