GitBucket
Newer
/*
* Copyright (c) Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <vapours/common.hpp>
#include <vapours/assert.hpp>
namespace ams::util {
namespace impl {
template<typename T>
struct AtomicIntegerStorage;
template<typename T> requires (sizeof(T) == sizeof(u8))
struct AtomicIntegerStorage<T> {
using Type = u8;
};
template<typename T> requires (sizeof(T) == sizeof(u16))
struct AtomicIntegerStorage<T> {
using Type = u16;
};
template<typename T> requires (sizeof(T) == sizeof(u32))
struct AtomicIntegerStorage<T> {
using Type = u32;
};
template<typename T> requires (sizeof(T) == sizeof(u64))
struct AtomicIntegerStorage<T> {
using Type = u64;
};
template<typename T>
concept UsableAtomicType = (sizeof(T) <= sizeof(u64)) && !std::is_const<T>::value && !std::is_volatile<T>::value && (std::is_pointer<T>::value || requires (const T &t) {
std::bit_cast<typename AtomicIntegerStorage<T>::Type, T>(t);
});
template<UsableAtomicType T>
using AtomicStorage = typename AtomicIntegerStorage<T>::Type;
static_assert(std::same_as<AtomicStorage<void *>, uintptr_t>);
static_assert(std::same_as<AtomicStorage<s8>, u8>);
static_assert(std::same_as<AtomicStorage<u8>, u8>);
static_assert(std::same_as<AtomicStorage<s16>, u16>);
static_assert(std::same_as<AtomicStorage<u16>, u16>);
static_assert(std::same_as<AtomicStorage<s32>, u32>);
static_assert(std::same_as<AtomicStorage<u32>, u32>);
static_assert(std::same_as<AtomicStorage<s64>, u64>);
static_assert(std::same_as<AtomicStorage<u64>, u64>);
ALWAYS_INLINE void ClearExclusiveForAtomic() {
__asm__ __volatile__("clrex" ::: "memory");
}
#define AMS_UTIL_IMPL_DEFINE_ATOMIC_LOAD_FUNCTION(_FNAME_, _MNEMONIC_) \
template<std::unsigned_integral T> T _FNAME_ ##ForAtomic(const volatile T *); \
\
template<> ALWAYS_INLINE u8 _FNAME_ ##ForAtomic(const volatile u8 *p) { u8 v; __asm__ __volatile__(_MNEMONIC_ "b %w[v], %[p]" : [v]"=r"(v) : [p]"Q"(*p) : "memory"); return v; } \
template<> ALWAYS_INLINE u16 _FNAME_ ##ForAtomic(const volatile u16 *p) { u16 v; __asm__ __volatile__(_MNEMONIC_ "h %w[v], %[p]" : [v]"=r"(v) : [p]"Q"(*p) : "memory"); return v; } \
template<> ALWAYS_INLINE u32 _FNAME_ ##ForAtomic(const volatile u32 *p) { u32 v; __asm__ __volatile__(_MNEMONIC_ " %w[v], %[p]" : [v]"=r"(v) : [p]"Q"(*p) : "memory"); return v; } \
template<> ALWAYS_INLINE u64 _FNAME_ ##ForAtomic(const volatile u64 *p) { u64 v; __asm__ __volatile__(_MNEMONIC_ " %[v], %[p]" : [v]"=r"(v) : [p]"Q"(*p) : "memory"); return v; }
AMS_UTIL_IMPL_DEFINE_ATOMIC_LOAD_FUNCTION(LoadAcquire, "ldar")
AMS_UTIL_IMPL_DEFINE_ATOMIC_LOAD_FUNCTION(LoadExclusive, "ldxr")
AMS_UTIL_IMPL_DEFINE_ATOMIC_LOAD_FUNCTION(LoadAcquireExclusive, "ldaxr")
#undef AMS_UTIL_IMPL_DEFINE_ATOMIC_LOAD_FUNCTION
template<std::unsigned_integral T> void StoreReleaseForAtomic(volatile T *, T);
template<> ALWAYS_INLINE void StoreReleaseForAtomic(volatile u8 *p, u8 v) { __asm__ __volatile__("stlrb %w[v], %[p]" : : [v]"r"(v), [p]"Q"(*p) : "memory"); }
template<> ALWAYS_INLINE void StoreReleaseForAtomic(volatile u16 *p, u16 v) { __asm__ __volatile__("stlrh %w[v], %[p]" : : [v]"r"(v), [p]"Q"(*p) : "memory"); }
template<> ALWAYS_INLINE void StoreReleaseForAtomic(volatile u32 *p, u32 v) { __asm__ __volatile__("stlr %w[v], %[p]" : : [v]"r"(v), [p]"Q"(*p) : "memory"); }
template<> ALWAYS_INLINE void StoreReleaseForAtomic(volatile u64 *p, u64 v) { __asm__ __volatile__("stlr %[v], %[p]" : : [v]"r"(v), [p]"Q"(*p) : "memory"); }
#define AMS_UTIL_IMPL_DEFINE_ATOMIC_STORE_EXCLUSIVE_FUNCTION(_FNAME_, _MNEMONIC_) \
template<std::unsigned_integral T> bool _FNAME_ ##ForAtomic(volatile T *, T); \
\
template<> ALWAYS_INLINE bool _FNAME_ ##ForAtomic(volatile u8 *p, u8 v) { int result; __asm__ __volatile__(_MNEMONIC_ "b %w[result], %w[v], %[p]" : [result]"=&r"(result) : [v]"r"(v), [p]"Q"(*p) : "memory"); return result == 0; } \
template<> ALWAYS_INLINE bool _FNAME_ ##ForAtomic(volatile u16 *p, u16 v) { int result; __asm__ __volatile__(_MNEMONIC_ "h %w[result], %w[v], %[p]" : [result]"=&r"(result) : [v]"r"(v), [p]"Q"(*p) : "memory"); return result == 0; } \
template<> ALWAYS_INLINE bool _FNAME_ ##ForAtomic(volatile u32 *p, u32 v) { int result; __asm__ __volatile__(_MNEMONIC_ " %w[result], %w[v], %[p]" : [result]"=&r"(result) : [v]"r"(v), [p]"Q"(*p) : "memory"); return result == 0; } \
template<> ALWAYS_INLINE bool _FNAME_ ##ForAtomic(volatile u64 *p, u64 v) { int result; __asm__ __volatile__(_MNEMONIC_ " %w[result], %[v], %[p]" : [result]"=&r"(result) : [v]"r"(v), [p]"Q"(*p) : "memory"); return result == 0; }
AMS_UTIL_IMPL_DEFINE_ATOMIC_STORE_EXCLUSIVE_FUNCTION(StoreExclusive, "stxr")
AMS_UTIL_IMPL_DEFINE_ATOMIC_STORE_EXCLUSIVE_FUNCTION(StoreReleaseExclusive, "stlxr")
#undef AMS_UTIL_IMPL_DEFINE_ATOMIC_STORE_EXCLUSIVE_FUNCTION
}
template<impl::UsableAtomicType T>
class Atomic {
NON_COPYABLE(Atomic);
NON_MOVEABLE(Atomic);
private:
using StorageType = impl::AtomicStorage<T>;
static constexpr bool IsIntegral = std::integral<T>;
static constexpr bool IsPointer = std::is_pointer<T>::value;
static constexpr bool HasArithmeticFunctions = IsIntegral || IsPointer;
using DifferenceType = typename std::conditional<IsIntegral, T, typename std::conditional<IsPointer, std::ptrdiff_t, void>::type>::type;
static constexpr ALWAYS_INLINE T ConvertToType(StorageType s) {
if constexpr (std::integral<T>) {
return static_cast<T>(s);
} else if constexpr(std::is_pointer<T>::value) {
return reinterpret_cast<T>(s);
} else {
return std::bit_cast<T>(s);
}
}
static constexpr ALWAYS_INLINE StorageType ConvertToStorage(T arg) {
if constexpr (std::integral<T>) {
return static_cast<StorageType>(arg);
} else if constexpr(std::is_pointer<T>::value) {
if (std::is_constant_evaluated() && arg == nullptr) {
return 0;
}
return reinterpret_cast<StorageType>(arg);
} else {
return std::bit_cast<StorageType>(arg);
}
}
private:
StorageType m_v;
private:
ALWAYS_INLINE volatile StorageType *GetStoragePointer() { return reinterpret_cast< volatile StorageType *>(std::addressof(m_v)); }
ALWAYS_INLINE const volatile StorageType *GetStoragePointer() const { return reinterpret_cast<const volatile StorageType *>(std::addressof(m_v)); }
public:
ALWAYS_INLINE Atomic() { /* ... */ }
constexpr ALWAYS_INLINE Atomic(T v) : m_v(ConvertToStorage(v)) { /* ... */ }
constexpr ALWAYS_INLINE T operator=(T desired) {
if (std::is_constant_evaluated()) {
m_v = ConvertToStorage(desired);
} else {
this->Store(desired);
}
return desired;
}
template<std::memory_order Order = std::memory_order_seq_cst>
ALWAYS_INLINE T Load() const {
if constexpr (Order != std::memory_order_relaxed) {
return ConvertToType(impl::LoadAcquireForAtomic(this->GetStoragePointer()));
} else {
return ConvertToType(*this->GetStoragePointer());
}
}
template<std::memory_order Order = std::memory_order_seq_cst>
ALWAYS_INLINE void Store(T arg) {
if constexpr (Order != std::memory_order_relaxed) {
impl::StoreReleaseForAtomic(this->GetStoragePointer(), ConvertToStorage(arg));
} else {
*this->GetStoragePointer() = ConvertToStorage(arg);
}
}
template<std::memory_order Order = std::memory_order_seq_cst>
ALWAYS_INLINE T Exchange(T arg) {
volatile StorageType * const p = this->GetStoragePointer();
const StorageType s = ConvertToStorage(arg);
StorageType current;
if constexpr (Order == std::memory_order_relaxed) {
do {
current = impl::LoadExclusiveForAtomic(p);
} while (AMS_UNLIKELY(!impl::StoreExclusiveForAtomic(p, s)));
} else if constexpr (Order == std::memory_order_consume || Order == std::memory_order_acquire) {
do {
current = impl::LoadAcquireExclusiveForAtomic(p);
} while (AMS_UNLIKELY(!impl::StoreExclusiveForAtomic(p, s)));
} else if constexpr (Order == std::memory_order_release) {
do {
current = impl::LoadExclusiveForAtomic(p);
} while (AMS_UNLIKELY(!impl::StoreReleaseExclusiveForAtomic(p, s)));
} else if constexpr (Order == std::memory_order_acq_rel || Order == std::memory_order_seq_cst) {
do {
current = impl::LoadAcquireExclusiveForAtomic(p);
} while (AMS_UNLIKELY(!impl::StoreReleaseExclusiveForAtomic(p, s)));
} else {
static_assert(Order != Order, "Invalid memory order");
}
return current;
}
template<std::memory_order Order = std::memory_order_seq_cst>
ALWAYS_INLINE bool CompareExchangeWeak(T &expected, T desired) {
volatile StorageType * const p = this->GetStoragePointer();
const StorageType e = ConvertToStorage(expected);
const StorageType d = ConvertToStorage(desired);
if constexpr (Order == std::memory_order_relaxed) {
const StorageType current = impl::LoadExclusiveForAtomic(p);
if (AMS_UNLIKELY(current != e)) {
impl::ClearExclusiveForAtomic();
expected = ConvertToType(current);
return false;
}
return AMS_LIKELY(impl::StoreExclusiveForAtomic(p, d));
} else if constexpr (Order == std::memory_order_consume || Order == std::memory_order_acquire) {
const StorageType current = impl::LoadAcquireExclusiveForAtomic(p);
if (AMS_UNLIKELY(current != e)) {
impl::ClearExclusiveForAtomic();
expected = ConvertToType(current);
return false;
}
return AMS_LIKELY(impl::StoreExclusiveForAtomic(p, d));
} else if constexpr (Order == std::memory_order_release) {
const StorageType current = impl::LoadExclusiveForAtomic(p);
if (AMS_UNLIKELY(current != e)) {
impl::ClearExclusiveForAtomic();
expected = ConvertToType(current);
return false;
}
return AMS_LIKELY(impl::StoreReleaseExclusiveForAtomic(p, d));
} else if constexpr (Order == std::memory_order_acq_rel || Order == std::memory_order_seq_cst) {
const StorageType current = impl::LoadAcquireExclusiveForAtomic(p);
if (AMS_UNLIKELY(current != e)) {
impl::ClearExclusiveForAtomic();
expected = ConvertToType(current);
return false;
}
return AMS_LIKELY(impl::StoreReleaseExclusiveForAtomic(p, d));
} else {
static_assert(Order != Order, "Invalid memory order");
}
}
template<std::memory_order Order = std::memory_order_seq_cst>
ALWAYS_INLINE bool CompareExchangeStrong(T &expected, T desired) {
volatile StorageType * const p = this->GetStoragePointer();
const StorageType e = ConvertToStorage(expected);
const StorageType d = ConvertToStorage(desired);
if constexpr (Order == std::memory_order_relaxed) {
StorageType current;
do {
if (current = impl::LoadExclusiveForAtomic(p); current != e) {
impl::ClearExclusiveForAtomic();
expected = ConvertToType(current);
return false;
}
} while (!impl::StoreExclusiveForAtomic(p, d));
} else if constexpr (Order == std::memory_order_consume || Order == std::memory_order_acquire) {
StorageType current;
do {
if (current = impl::LoadAcquireExclusiveForAtomic(p); current != e) {
impl::ClearExclusiveForAtomic();
expected = ConvertToType(current);
return false;
}
} while (!impl::StoreExclusiveForAtomic(p, d));
} else if constexpr (Order == std::memory_order_release) {
StorageType current;
do {
if (current = impl::LoadExclusiveForAtomic(p); current != e) {
impl::ClearExclusiveForAtomic();
expected = ConvertToType(current);
return false;
}
} while (!impl::StoreReleaseExclusiveForAtomic(p, d));
} else if constexpr (Order == std::memory_order_acq_rel || Order == std::memory_order_seq_cst) {
StorageType current;
do {
if (current = impl::LoadAcquireExclusiveForAtomic(p); current != e) {
impl::ClearExclusiveForAtomic();
expected = ConvertToType(current);
return false;
}
} while (!impl::StoreReleaseExclusiveForAtomic(p, d));
} else {
static_assert(Order != Order, "Invalid memory order");
}
return true;
}
#define AMS_UTIL_IMPL_DEFINE_ATOMIC_FETCH_OPERATE_FUNCTION(_OPERATION_, _OPERATOR_, _POINTER_ALLOWED_) \
template<bool Enable = (IsIntegral || (_POINTER_ALLOWED_ && IsPointer)), typename = typename std::enable_if<Enable, void>::type> \
ALWAYS_INLINE T Fetch ## _OPERATION_(DifferenceType arg) { \
static_assert(Enable == (IsIntegral || (_POINTER_ALLOWED_ && IsPointer))); \
volatile StorageType * const p = this->GetStoragePointer(); \
\
StorageType current; \
do { \
current = impl::LoadAcquireExclusiveForAtomic<StorageType>(p); \
} while (AMS_UNLIKELY(!impl::StoreReleaseExclusiveForAtomic<StorageType>(p, ConvertToStorage(ConvertToType(current) _OPERATOR_ arg)))); \
return ConvertToType(current); \
} \
\
template<bool Enable = (IsIntegral || (_POINTER_ALLOWED_ && IsPointer)), typename = typename std::enable_if<Enable, void>::type> \
ALWAYS_INLINE T operator _OPERATOR_##=(DifferenceType arg) { \
static_assert(Enable == (IsIntegral || (_POINTER_ALLOWED_ && IsPointer))); \
return this->Fetch ## _OPERATION_(arg) _OPERATOR_ arg; \
}
AMS_UTIL_IMPL_DEFINE_ATOMIC_FETCH_OPERATE_FUNCTION(Add, +, true)
AMS_UTIL_IMPL_DEFINE_ATOMIC_FETCH_OPERATE_FUNCTION(Sub, -, true)
AMS_UTIL_IMPL_DEFINE_ATOMIC_FETCH_OPERATE_FUNCTION(And, &, false)
AMS_UTIL_IMPL_DEFINE_ATOMIC_FETCH_OPERATE_FUNCTION(Or, |, false)
AMS_UTIL_IMPL_DEFINE_ATOMIC_FETCH_OPERATE_FUNCTION(Xor, ^, false)
#undef AMS_UTIL_IMPL_DEFINE_ATOMIC_FETCH_OPERATE_FUNCTION
template<bool Enable = HasArithmeticFunctions, typename = typename std::enable_if<Enable, void>::type>
ALWAYS_INLINE T operator++() { static_assert(Enable == HasArithmeticFunctions); return this->FetchAdd(1) + 1; }
template<bool Enable = HasArithmeticFunctions, typename = typename std::enable_if<Enable, void>::type>
ALWAYS_INLINE T operator++(int) { static_assert(Enable == HasArithmeticFunctions); return this->FetchAdd(1); }
template<bool Enable = HasArithmeticFunctions, typename = typename std::enable_if<Enable, void>::type>
ALWAYS_INLINE T operator--() { static_assert(Enable == HasArithmeticFunctions); return this->FetchSub(1) - 1; }
template<bool Enable = HasArithmeticFunctions, typename = typename std::enable_if<Enable, void>::type>
ALWAYS_INLINE T operator--(int) { static_assert(Enable == HasArithmeticFunctions); return this->FetchSub(1); }
};
}