Redcraft/Redcraft.Utility/Source/Public/Templates/Any.h
_Redstone_c_ 6a70d4273e fix(templates): fix FSingleton not working correctly with EBO on MSVC
make CAnyCustomStorage satisfy the concept of FSingleton
2022-11-18 23:18:58 +08:00

516 lines
19 KiB
C++

#pragma once
#include "CoreTypes.h"
#include "Memory/Memory.h"
#include "Memory/Alignment.h"
#include "Templates/Utility.h"
#include "Templates/TypeHash.h"
#include "Memory/MemoryOperator.h"
#include "TypeTraits/TypeTraits.h"
#include "Miscellaneous/AssertionMacros.h"
NAMESPACE_REDCRAFT_BEGIN
NAMESPACE_MODULE_BEGIN(Redcraft)
NAMESPACE_MODULE_BEGIN(Utility)
// TAny's CustomStorage concept, see FAnyDefaultStorage
template <typename T>
concept CAnyCustomStorage = CDefaultConstructible<T>
&& !CCopyConstructible<T> && !CMoveConstructible<T>
&& !CCopyAssignable<T> && !CMoveAssignable<T>
&& CDestructible<T>
&& CSameAs<decltype(T::InlineSize), const size_t>
&& CSameAs<decltype(T::InlineAlignment), const size_t>
&& requires(const T& A)
{
{ A.InlineAllocation() } -> CSameAs<const void*>;
{ A.HeapAllocation() } -> CSameAs<void*>;
{ A.TypeInfo() } -> CSameAs<uintptr>;
}
&& requires(T& A)
{
{ A.InlineAllocation() } -> CSameAs<void*>;
{ A.HeapAllocation() } -> CSameAs<void*&>;
{ A.TypeInfo() } -> CSameAs<uintptr&>;
}
&& requires(T& A, const T& B, T&& C)
{
A.CopyCustom(B);
A.MoveCustom(MoveTemp(C));
};
// TAny's default storage structure
struct alignas(16) FAnyDefaultStorage : FSingleton
{
// The built-in copy/move operators are disabled and CopyCustom/MoveCustom is used instead of them
// You can add custom variables like this
//Type Variable;
//~ Begin CAnyCustomStorage Interface
inline static constexpr size_t InlineSize = 64 - sizeof(uintptr);
inline static constexpr size_t InlineAlignment = 16;
constexpr void* InlineAllocation() { return &InlineAllocationImpl; }
constexpr const void* InlineAllocation() const { return &InlineAllocationImpl; }
constexpr void*& HeapAllocation() { return HeapAllocationImpl; }
constexpr void* HeapAllocation() const { return HeapAllocationImpl; }
constexpr uintptr& TypeInfo() { return TypeInfoImpl; }
constexpr uintptr TypeInfo() const { return TypeInfoImpl; }
constexpr void CopyCustom(const FAnyDefaultStorage& InValue) { /* Variable = InValue.Variable; */ } // You just need to copy the custom variables
constexpr void MoveCustom( FAnyDefaultStorage&& InValue) { /* Variable = MoveTemp(InValue.Variable); */ } // You just need to move the custom variables
//~ End CAnyCustomStorage Interface
union
{
uint8 InlineAllocationImpl[InlineSize];
void* HeapAllocationImpl;
};
uintptr TypeInfoImpl;
};
static_assert(CAnyCustomStorage<FAnyDefaultStorage>);
// You can add custom storage area through CustomStorage, such as TFunction
// It is not recommended to use this, FAny is recommended
template <CAnyCustomStorage CustomStorage = FAnyDefaultStorage>
class TAny
{
public:
inline static constexpr size_t InlineSize = CustomStorage::InlineSize;
inline static constexpr size_t InlineAlignment = CustomStorage::InlineAlignment;
constexpr TAny() { Storage.TypeInfo() = 0; }
constexpr TAny(FInvalid) : TAny() { }
FORCEINLINE TAny(const TAny& InValue)
{
Storage.CopyCustom(InValue.Storage);
Storage.TypeInfo() = InValue.Storage.TypeInfo();
if (!IsValid()) return;
switch (GetRepresentation())
{
case ERepresentation::Trivial:
Memory::Memcpy(Storage.InlineAllocation(), InValue.Storage.InlineAllocation(), Storage.InlineSize);
break;
case ERepresentation::Small:
GetTypeInfoImpl().CopyConstructImpl(GetAllocation(), InValue.GetAllocation());
break;
case ERepresentation::Big:
Storage.HeapAllocation() = Memory::Malloc(GetTypeInfoImpl().TypeSize, GetTypeInfoImpl().TypeAlignment);
GetTypeInfoImpl().CopyConstructImpl(GetAllocation(), InValue.GetAllocation());
break;
default: check_no_entry();
}
}
FORCEINLINE TAny(TAny&& InValue)
{
Storage.MoveCustom(MoveTemp(InValue.Storage));
Storage.TypeInfo() = InValue.Storage.TypeInfo();
if (!IsValid()) return;
switch (GetRepresentation())
{
case ERepresentation::Trivial:
Memory::Memcpy(Storage.InlineAllocation(), InValue.Storage.InlineAllocation(), Storage.InlineSize);
break;
case ERepresentation::Small:
GetTypeInfoImpl().MoveConstructImpl(GetAllocation(), InValue.GetAllocation());
break;
case ERepresentation::Big:
Storage.HeapAllocation() = InValue.Storage.HeapAllocation();
InValue.Storage.TypeInfo() = 0;
break;
default: check_no_entry();
}
}
template <typename T, typename... Ts> requires (CDestructible<TDecay<T>>
&& CConstructibleFrom<TDecay<T>, Ts&&...>)
FORCEINLINE explicit TAny(TInPlaceType<T>, Ts&&... Args)
{
using SelectedType = TDecay<T>;
EmplaceImpl<SelectedType>(Forward<Ts>(Args)...);
}
template <typename T> requires (!CSameAs<TDecay<T>, TAny> && !CTInPlaceType<TDecay<T>>)
&& CDestructible<TDecay<T>> && CConstructibleFrom<TDecay<T>, T&&>
FORCEINLINE TAny(T&& InValue) : TAny(InPlaceType<TDecay<T>>, Forward<T>(InValue))
{ }
FORCEINLINE ~TAny()
{
ResetImpl();
}
FORCEINLINE TAny& operator=(const TAny& InValue)
{
if (&InValue == this) return *this;
Storage.CopyCustom(InValue.Storage);
if (!InValue.IsValid())
{
Reset();
}
else if (GetTypeInfo() == InValue.GetTypeInfo())
{
switch (GetRepresentation())
{
case ERepresentation::Trivial:
Memory::Memcpy(Storage.InlineAllocation(), InValue.Storage.InlineAllocation(), Storage.InlineSize);
break;
case ERepresentation::Small:
case ERepresentation::Big:
GetTypeInfoImpl().CopyAssignImpl(GetAllocation(), InValue.GetAllocation());
break;
default: check_no_entry();
}
}
else
{
ResetImpl();
Storage.TypeInfo() = InValue.Storage.TypeInfo();
switch (GetRepresentation())
{
case ERepresentation::Trivial:
Memory::Memcpy(Storage.InlineAllocation(), InValue.Storage.InlineAllocation(), Storage.InlineSize);
break;
case ERepresentation::Small:
GetTypeInfoImpl().CopyConstructImpl(GetAllocation(), InValue.GetAllocation());
break;
case ERepresentation::Big:
Storage.HeapAllocation() = Memory::Malloc(GetTypeInfoImpl().TypeSize, GetTypeInfoImpl().TypeAlignment);
GetTypeInfoImpl().CopyConstructImpl(GetAllocation(), InValue.GetAllocation());
break;
default: check_no_entry();
}
}
return *this;
}
FORCEINLINE TAny& operator=(TAny&& InValue)
{
if (&InValue == this) return *this;
Storage.MoveCustom(MoveTemp(InValue.Storage));
if (!InValue.IsValid())
{
Reset();
}
else if (GetTypeInfo() == InValue.GetTypeInfo())
{
switch (GetRepresentation())
{
case ERepresentation::Trivial:
Memory::Memcpy(Storage.InlineAllocation(), InValue.Storage.InlineAllocation(), Storage.InlineSize);
break;
case ERepresentation::Small:
GetTypeInfoImpl().MoveAssignImpl(GetAllocation(), InValue.GetAllocation());
break;
case ERepresentation::Big:
ResetImpl();
Storage.HeapAllocation() = InValue.Storage.HeapAllocation();
InValue.Storage.TypeInfo() = 0;
break;
default: check_no_entry();
}
}
else
{
ResetImpl();
Storage.TypeInfo() = InValue.Storage.TypeInfo();
switch (GetRepresentation())
{
case ERepresentation::Trivial:
Memory::Memcpy(Storage.InlineAllocation(), InValue.Storage.InlineAllocation(), Storage.InlineSize);
break;
case ERepresentation::Small:
GetTypeInfoImpl().MoveConstructImpl(GetAllocation(), InValue.GetAllocation());
break;
case ERepresentation::Big:
Storage.HeapAllocation() = InValue.Storage.HeapAllocation();
InValue.Storage.TypeInfo() = 0;
break;
default: check_no_entry();
}
}
return *this;
}
template <typename T> requires (!CSameAs<TDecay<T>, TAny> && !CTInPlaceType<TDecay<T>>)
&& CDestructible<TDecay<T>> && CConstructibleFrom<TDecay<T>, T&&>
FORCEINLINE TAny& operator=(T&& InValue)
{
using SelectedType = TDecay<T>;
if (HoldsAlternative<SelectedType>())
{
GetValue<SelectedType>() = Forward<T>(InValue);
}
else
{
ResetImpl();
EmplaceImpl<SelectedType>(Forward<T>(InValue));
}
return *this;
}
template <typename T, typename... Ts> requires (CDestructible<TDecay<T>>
&& CConstructibleFrom<TDecay<T>, Ts&&...>)
FORCEINLINE TDecay<T>& Emplace(Ts&&... Args)
{
ResetImpl();
using SelectedType = TDecay<T>;
EmplaceImpl<SelectedType>(Forward<Ts>(Args)...);
return GetValue<SelectedType>();
}
constexpr const type_info& GetTypeInfo() const { return IsValid() ? *GetTypeInfoImpl().NativeTypeInfo : typeid(void); }
constexpr bool IsValid() const { return Storage.TypeInfo() != 0; }
constexpr explicit operator bool() const { return Storage.TypeInfo() != 0; }
template <typename T> constexpr bool HoldsAlternative() const { return IsValid() ? GetTypeInfo() == typeid(T) : false; }
template <typename T> requires (CDestructible<TDecay<T>>)
constexpr T& GetValue() & { checkf(HoldsAlternative<T>(), TEXT("It is an error to call GetValue() on an wrong TAny. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return *reinterpret_cast< T*>(GetAllocation()); }
template <typename T> requires (CDestructible<TDecay<T>>)
constexpr T&& GetValue() && { checkf(HoldsAlternative<T>(), TEXT("It is an error to call GetValue() on an wrong TAny. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return MoveTemp(*reinterpret_cast< T*>(GetAllocation())); }
template <typename T> requires (CDestructible<TDecay<T>>)
constexpr const T& GetValue() const& { checkf(HoldsAlternative<T>(), TEXT("It is an error to call GetValue() on an wrong TAny. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return *reinterpret_cast<const T*>(GetAllocation()); }
template <typename T> requires (CDestructible<TDecay<T>>)
constexpr const T&& GetValue() const&& { checkf(HoldsAlternative<T>(), TEXT("It is an error to call GetValue() on an wrong TAny. Please either check HoldsAlternative() or use Get(DefaultValue) instead.")); return MoveTemp(*reinterpret_cast<const T*>(GetAllocation())); }
template <typename T> requires (CSameAs<T, TDecay<T>> && CDestructible<TDecay<T>>)
constexpr T& Get( T& DefaultValue) & { return HoldsAlternative<T>() ? GetValue<T>() : DefaultValue; }
template <typename T> requires (CSameAs<T, TDecay<T>> && CDestructible<TDecay<T>>)
constexpr const T& Get(const T& DefaultValue) const& { return HoldsAlternative<T>() ? GetValue<T>() : DefaultValue; }
constexpr CustomStorage& GetCustomStorage() requires (!CSameAs<CustomStorage, FAnyDefaultStorage>) { return Storage; }
constexpr const CustomStorage& GetCustomStorage() const requires (!CSameAs<CustomStorage, FAnyDefaultStorage>) { return Storage; }
FORCEINLINE void Reset()
{
ResetImpl();
Storage.TypeInfo() = 0;
}
FORCEINLINE size_t GetTypeHash() const
{
using NAMESPACE_REDCRAFT::GetTypeHash;
if (!IsValid()) return 20090007;
return HashCombine(GetTypeHash(GetTypeInfo()), GetTypeInfoImpl().HashImpl(GetAllocation()));
}
FORCEINLINE void Swap(TAny& InValue)
{
if (!IsValid() && !InValue.IsValid()) return;
if (IsValid() && !InValue.IsValid())
{
InValue = MoveTemp(*this);
Reset();
return;
}
if (InValue.IsValid() && !IsValid())
{
*this = MoveTemp(InValue);
InValue.Reset();
return;
}
if (GetTypeInfo() == InValue.GetTypeInfo())
{
GetTypeInfoImpl().SwapImpl(GetAllocation(), InValue.GetAllocation());
return;
}
TAny Temp = MoveTemp(*this);
*this = MoveTemp(InValue);
InValue = MoveTemp(Temp);
}
private:
CustomStorage Storage;
static constexpr uintptr_t RepresentationMask = 3;
enum class ERepresentation : uint8
{
Trivial, // Trivial & Inline
Small, // InlineAllocation
Big, // HeapAllocation
};
struct FTypeInfoImpl
{
const type_info* NativeTypeInfo;
const size_t TypeSize;
const size_t TypeAlignment;
using FCopyConstructImpl = void(*)(void*, const void*);
using FMoveConstructImpl = void(*)(void*, void*);
using FCopyAssignImpl = void(*)(void*, const void*);
using FMoveAssignImpl = void(*)(void*, void*);
using FDestroyImpl = void(*)(void* );
using FEqualityCompareImpl = bool (*)(const void*, const void*);
using FSynthThreeWayCompareImpl = partial_ordering (*)(const void*, const void*);
using FHashImpl = size_t (*)(const void* );
using FSwapImpl = void (*)( void*, void*);
const FCopyConstructImpl CopyConstructImpl;
const FMoveConstructImpl MoveConstructImpl;
const FCopyAssignImpl CopyAssignImpl;
const FMoveAssignImpl MoveAssignImpl;
const FDestroyImpl DestroyImpl;
const FEqualityCompareImpl EqualityCompareImpl;
const FSynthThreeWayCompareImpl SynthThreeWayCompareImpl;
const FHashImpl HashImpl;
const FSwapImpl SwapImpl;
template <typename T>
constexpr FTypeInfoImpl(TInPlaceType<T>)
: NativeTypeInfo (&typeid(T))
, TypeSize ( sizeof(T))
, TypeAlignment (alignof(T))
, CopyConstructImpl ([](void* A, const void* B) { if constexpr (requires(T* A, const T* B) { Memory::CopyConstruct (A, B); }) Memory::CopyConstruct (reinterpret_cast<T*>(A), reinterpret_cast<const T*>(B)); else checkf(false, TEXT("The type '%s' is not copy constructible."), typeid(T).name()); })
, MoveConstructImpl ([](void* A, void* B) { if constexpr (requires(T* A, T* B) { Memory::MoveConstruct (A, B); }) Memory::MoveConstruct (reinterpret_cast<T*>(A), reinterpret_cast< T*>(B)); else checkf(false, TEXT("The type '%s' is not move constructible."), typeid(T).name()); })
, CopyAssignImpl ([](void* A, const void* B) { if constexpr (requires(T* A, const T* B) { Memory::CopyAssign (A, B); }) Memory::CopyAssign (reinterpret_cast<T*>(A), reinterpret_cast<const T*>(B)); else checkf(false, TEXT("The type '%s' is not copy assignable."), typeid(T).name()); })
, MoveAssignImpl ([](void* A, void* B) { if constexpr (requires(T* A, T* B) { Memory::MoveAssign (A, B); }) Memory::MoveAssign (reinterpret_cast<T*>(A), reinterpret_cast< T*>(B)); else checkf(false, TEXT("The type '%s' is not move assignable."), typeid(T).name()); })
, DestroyImpl ([](void* A ) { if constexpr (requires(T* A ) { Memory::Destruct (A ); }) Memory::Destruct (reinterpret_cast<T*>(A) ); else checkf(false, TEXT("The type '%s' is not destructible."), typeid(T).name()); })
, EqualityCompareImpl ([](const void* A, const void* B) -> bool { if constexpr (CEqualityComparable<T> ) return (*reinterpret_cast<const T*>(A) == *reinterpret_cast<const T*>(B)); else checkf(false, TEXT("The type '%s' is not equality comparable."), typeid(T).name()); return false; })
, SynthThreeWayCompareImpl ([](const void* A, const void* B) -> partial_ordering { if constexpr (CSynthThreeWayComparable<T>) return NAMESPACE_REDCRAFT::SynthThreeWayCompare (*reinterpret_cast<const T*>(A), *reinterpret_cast<const T*>(B)); else checkf(false, TEXT("The type '%s' is not synth three-way comparable."), typeid(T).name()); return partial_ordering::unordered; })
, HashImpl ([](const void* A ) -> size_t { if constexpr (CHashable<T> ) return NAMESPACE_REDCRAFT::GetTypeHash (*reinterpret_cast<const T*>(A) ); else checkf(false, TEXT("The type '%s' is not hashable."), typeid(T).name()); return 1080551797; })
, SwapImpl ([]( void* A, void* B) -> void { if constexpr (CSwappable<T> ) NAMESPACE_REDCRAFT::Swap (*reinterpret_cast< T*>(A), *reinterpret_cast< T*>(B)); else checkf(false, TEXT("The type '%s' is not swappable."), typeid(T).name()); })
{ }
};
constexpr ERepresentation GetRepresentation() const { return static_cast<ERepresentation>(Storage.TypeInfo() & RepresentationMask); }
constexpr const FTypeInfoImpl& GetTypeInfoImpl() const { return *reinterpret_cast<const FTypeInfoImpl*>(Storage.TypeInfo() & ~RepresentationMask); }
constexpr void* GetAllocation() { return GetRepresentation() == ERepresentation::Trivial || GetRepresentation() == ERepresentation::Small ? Storage.InlineAllocation() : Storage.HeapAllocation(); }
constexpr const void* GetAllocation() const { return GetRepresentation() == ERepresentation::Trivial || GetRepresentation() == ERepresentation::Small ? Storage.InlineAllocation() : Storage.HeapAllocation(); }
template <typename SelectedType, typename... Ts>
FORCEINLINE void EmplaceImpl(Ts&&... Args)
{
static constexpr const FTypeInfoImpl SelectedTypeInfo(InPlaceType<SelectedType>);
Storage.TypeInfo() = reinterpret_cast<uintptr>(&SelectedTypeInfo);
constexpr bool bIsInlineStorable = sizeof(SelectedType) <= Storage.InlineSize && alignof(SelectedType) <= Storage.InlineAlignment;
constexpr bool bIsTriviallyStorable = bIsInlineStorable && CTrivial<SelectedType> && CTriviallyCopyable<SelectedType>;
if constexpr (bIsTriviallyStorable)
{
new(Storage.InlineAllocation()) SelectedType(Forward<Ts>(Args)...);
Storage.TypeInfo() |= static_cast<uintptr>(ERepresentation::Trivial);
}
else if constexpr (bIsInlineStorable)
{
new(Storage.InlineAllocation()) SelectedType(Forward<Ts>(Args)...);
Storage.TypeInfo() |= static_cast<uintptr>(ERepresentation::Small);
}
else
{
Storage.HeapAllocation() = new SelectedType(Forward<Ts>(Args)...);
Storage.TypeInfo() |= static_cast<uintptr>(ERepresentation::Big);
}
}
FORCEINLINE void ResetImpl()
{
if (!IsValid()) return;
switch (GetRepresentation())
{
case ERepresentation::Trivial:
break;
case ERepresentation::Small:
GetTypeInfoImpl().DestroyImpl(GetAllocation());
break;
case ERepresentation::Big:
GetTypeInfoImpl().DestroyImpl(GetAllocation());
Memory::Free(Storage.HeapAllocation());
break;
default: check_no_entry();
}
}
friend FORCEINLINE bool operator==(const TAny& LHS, const TAny& RHS)
{
if (LHS.GetTypeInfo() != RHS.GetTypeInfo()) return false;
if (LHS.IsValid() == false) return true;
return LHS.GetTypeInfoImpl().EqualityCompareImpl(LHS.GetAllocation(), RHS.GetAllocation());
}
friend FORCEINLINE partial_ordering operator<=>(const TAny& LHS, const TAny& RHS)
{
if (LHS.GetTypeInfo() != RHS.GetTypeInfo()) return partial_ordering::unordered;
if (LHS.IsValid() == false) return partial_ordering::equivalent;
return LHS.GetTypeInfoImpl().SynthThreeWayCompareImpl(LHS.GetAllocation(), RHS.GetAllocation());;
}
};
template <typename T, CAnyCustomStorage StorageType>
constexpr bool operator==(const TAny<StorageType>& LHS, const T& RHS)
{
return LHS.template HoldsAlternative<T>() ? LHS.template GetValue<T>() == RHS : false;
}
template <CAnyCustomStorage StorageType>
constexpr bool operator==(const TAny<StorageType>& LHS, FInvalid)
{
return !LHS.IsValid();
}
NAMESPACE_PRIVATE_BEGIN
template <typename T> struct TIsTAny : FFalse { };
template <CAnyCustomStorage StorageType> struct TIsTAny<TAny<StorageType>> : FTrue { };
NAMESPACE_PRIVATE_END
template <typename T>
concept CTAny = NAMESPACE_PRIVATE::TIsTAny<TRemoveCV<T>>::Value;
using FAny = TAny<>;
static_assert(sizeof(FAny) == 64, "The byte size of FAny is unexpected");
NAMESPACE_MODULE_END(Utility)
NAMESPACE_MODULE_END(Redcraft)
NAMESPACE_REDCRAFT_END