drinkingtea/nostalgia
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[ox/std] Silently suppress small Vector in constexpr

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This commit is contained in:
Gary Talent 2022-02-05 01:33:08 -06:00
parent 60b97094b0
commit 50eb01115d
1 changed files with 19 additions and 18 deletions
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37
deps/ox/src/ox/std/vector.hpp vendored
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@ -22,25 +22,25 @@ namespace ox {
namespace detail { namespace detail {
template<typename T, std::size_t Size> template<typename T, std::size_t Size>
struct SmallVector { struct VectorAllocator {
private: private:
std::allocator<T> m_allocator; std::allocator<T> m_allocator;
AllocAlias<T> m_data[Size] = {}; AllocAlias<T> m_data[Size] = {};
public: public:
SmallVector() noexcept = default; constexpr VectorAllocator() noexcept = default;
SmallVector(SmallVector&) noexcept = default; constexpr VectorAllocator(VectorAllocator&) noexcept = default;
SmallVector(SmallVector&&) noexcept = default; constexpr VectorAllocator(VectorAllocator&&) noexcept = default;
protected: protected:
constexpr void allocate(T **items, std::size_t cap) noexcept { constexpr void allocate(T **items, std::size_t cap) noexcept {
if (cap <= Size) { // small vector optimization cannot be done it constexpr, but it doesn't really matter in constexpr
*items = reinterpret_cast<T*>(m_data); if (std::is_constant_evaluated() || cap > Size) {
} else {
*items = m_allocator.allocate(cap); *items = m_allocator.allocate(cap);
} else {
*items = reinterpret_cast<T*>(m_data);
} }
} }
constexpr void moveConstructItemsFrom(T **items, SmallVector &src, const std::size_t count, const std::size_t cap) noexcept { constexpr void moveConstructItemsFrom(T **items, VectorAllocator &src, const std::size_t count, const std::size_t cap) noexcept {
if (cap <= Size) { if (cap <= Size) {
const auto dstItems = reinterpret_cast<T*>(m_data); const auto dstItems = reinterpret_cast<T*>(m_data);
const auto srcItems = reinterpret_cast<T*>(src.m_data); const auto srcItems = reinterpret_cast<T*>(src.m_data);
@ -51,7 +51,7 @@ struct SmallVector {
} }
} }
constexpr void moveItemsFrom(T **items, SmallVector &src, const std::size_t count, const std::size_t cap) noexcept { constexpr void moveItemsFrom(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, // this totally idiotic redundant check (&& count <= Size) is required to address a bug in devkitARM,
// try removing it later // try removing it later
if (cap <= Size && count <= Size) { if (cap <= Size && count <= Size) {
@ -65,7 +65,8 @@ struct SmallVector {
} }
constexpr void deallocate(T *items, std::size_t cap) noexcept { constexpr void deallocate(T *items, std::size_t cap) noexcept {
if (items && static_cast<void*>(items) != static_cast<void*>(m_data)) { // small vector optimization cannot be done it constexpr, but it doesn't really matter in constexpr
if (std::is_constant_evaluated() || (items && static_cast<void*>(items) != static_cast<void*>(m_data))) {
m_allocator.deallocate(items, cap); m_allocator.deallocate(items, cap);
} }
} }
@ -73,24 +74,24 @@ struct SmallVector {
}; };
template<typename T> template<typename T>
struct SmallVector<T, 0> { struct VectorAllocator<T, 0> {
private: private:
std::allocator<T> m_allocator; std::allocator<T> m_allocator;
public: public:
SmallVector() noexcept = default; constexpr VectorAllocator() noexcept = default;
SmallVector(SmallVector&) noexcept = default; constexpr VectorAllocator(VectorAllocator&) noexcept = default;
SmallVector(SmallVector&&) noexcept = default; constexpr VectorAllocator(VectorAllocator&&) noexcept = default;
protected: protected:
constexpr void allocate(T **items, std::size_t cap) noexcept { constexpr void allocate(T **items, std::size_t cap) noexcept {
*items = m_allocator.allocate(cap); *items = m_allocator.allocate(cap);
} }
[[maybe_unused]] [[maybe_unused]]
constexpr void moveConstructItemsFrom(T**, SmallVector&, const std::size_t, const std::size_t) noexcept { constexpr void moveConstructItemsFrom(T**, VectorAllocator&, const std::size_t, const std::size_t) noexcept {
} }
[[maybe_unused]] [[maybe_unused]]
constexpr void moveItemsFrom(T**, SmallVector&, const std::size_t, const std::size_t) noexcept { constexpr void moveItemsFrom(T**, VectorAllocator&, const std::size_t, const std::size_t) noexcept {
} }
constexpr void deallocate(T *items, std::size_t cap) noexcept { constexpr void deallocate(T *items, std::size_t cap) noexcept {
@ -104,7 +105,7 @@ struct SmallVector<T, 0> {
} }
template<typename T, std::size_t SmallVectorSize = 0> template<typename T, std::size_t SmallVectorSize = 0>
class Vector: detail::SmallVector<T, SmallVectorSize> { class Vector: detail::VectorAllocator<T, SmallVectorSize> {
public: public:
using value_type = T; using value_type = T;