1 files changed, 238 insertions, 0 deletions
diff --git a/AK/Atomic.h b/AK/Atomic.h
new file mode 100644
index 0000000000..0ab0b19601
--- /dev/null
+++ b/AK/Atomic.h
@@ -0,0 +1,238 @@
+#pragma once
+
+namespace AK {
+
+enum MemoryOrder
+{
+	memory_order_relaxed = __ATOMIC_RELAXED,
+	memory_order_consume = __ATOMIC_CONSUME,
+	memory_order_acquire = __ATOMIC_ACQUIRE,
+	memory_order_release = __ATOMIC_RELEASE,
+	memory_order_acq_rel = __ATOMIC_ACQ_REL,
+	memory_order_seq_cst = __ATOMIC_SEQ_CST
+};
+
+template <typename T>
+class Atomic
+{
+	T m_value { 0 };
+
+public:
+	Atomic() noexcept = default;
+	Atomic(const Atomic&) = delete;
+	Atomic& operator=(const Atomic&) volatile = delete;
+
+	Atomic(T val) noexcept:
+		m_value(val)
+	{
+	}
+	
+	T exchange(T desired, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		return __atomic_exchange_n(&m_value, desired, order);
+	}
+	
+	bool compare_exchange_strong(T& expected, T desired, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		if (order == memory_order_acq_rel || order == memory_order_release)
+			return __atomic_compare_exchange_n(&m_value, &expected, desired, false, memory_order_release, memory_order_acquire);
+		else
+			return __atomic_compare_exchange_n(&m_value, &expected, desired, false, order, order);
+	}
+	
+	T operator++() volatile noexcept
+	{
+		return fetch_add(1) + 1;
+	}
+	
+	T operator++(int) volatile noexcept
+	{
+		return fetch_add(1);
+	}
+	
+	T operator+=(T val) volatile noexcept
+	{
+		return fetch_add(val) + val;
+	}
+	
+	T fetch_add(T val, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		return __atomic_fetch_add(&m_value, val, order);
+	}
+	
+	T operator--() volatile noexcept
+	{
+		return fetch_sub(1) - 1;
+	}
+	
+	T operator--(int) volatile noexcept
+	{
+		return fetch_sub(1);
+	}
+	
+	T operator-=(T val) volatile noexcept
+	{
+		return fetch_sub(val) - val;
+	}
+	
+	T fetch_sub(T val, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		return __atomic_fetch_sub(&m_value, val, order);
+	}
+	
+	T operator&=(T val) volatile noexcept
+	{
+		return fetch_and(val) & val;
+	}
+	
+	T fetch_and(T val, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		return __atomic_fetch_and(&m_value, val, order);
+	}
+	
+	T operator|=(T val) volatile noexcept
+	{
+		return fetch_or(val) | val;
+	}
+	
+	T fetch_or(T val, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		return __atomic_fetch_or(&m_value, val, order);
+	}
+	
+	T operator^=(T val) volatile noexcept
+	{
+		return fetch_xor(val) ^ val;
+	}
+	
+	T fetch_xor(T val, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		return __atomic_fetch_xor(&m_value, val, order);
+	}
+	
+	operator T() const volatile noexcept
+	{
+		return load();
+	}
+	
+	T load(MemoryOrder order = memory_order_seq_cst) const volatile noexcept
+	{
+		return __atomic_load_n(&m_value, order);
+	}
+	
+	T operator=(T desired) volatile noexcept
+	{
+		store(desired);
+		return desired;
+	}
+	
+	void store(T desired, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		__atomic_store_n(&m_value, desired, order);
+	}
+	
+	bool is_lock_free() const volatile noexcept
+	{
+		return __atomic_is_lock_free(sizeof(m_value), &m_value);
+	}
+};
+
+
+template <typename T>
+class Atomic<T*>
+{
+	T* m_value { nullptr };
+
+public:
+	Atomic() noexcept = default;
+	Atomic(const Atomic&) = delete;
+	Atomic& operator=(const Atomic&) volatile = delete;
+
+	Atomic(T* val) noexcept:
+		m_value(val)
+	{
+	}
+	
+	T* exchange(T* desired, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		return __atomic_exchange_n(&m_value, desired, order);
+	}
+	
+	bool compare_exchange_strong(T*& expected, T* desired, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		if (order == memory_order_acq_rel || order == memory_order_release)
+			return __atomic_compare_exchange_n(&m_value, &expected, desired, false, memory_order_release, memory_order_acquire);
+		else
+			return __atomic_compare_exchange_n(&m_value, &expected, desired, false, order, order);
+	}
+	
+	T* operator++() volatile noexcept
+	{
+		return fetch_add(1) + 1;
+	}
+	
+	T* operator++(int) volatile noexcept
+	{
+		return fetch_add(1);
+	}
+	
+	T* operator+=(ptrdiff_t val) volatile noexcept
+	{
+		return fetch_add(val) + val;
+	}
+	
+	T* fetch_add(ptrdiff_t val, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		return __atomic_fetch_add(&m_value, val * sizeof(*m_value), order);
+	}
+	
+	T* operator--() volatile noexcept
+	{
+		return fetch_sub(1) - 1;
+	}
+	
+	T* operator--(int) volatile noexcept
+	{
+		return fetch_sub(1);
+	}
+	
+	T* operator-=(ptrdiff_t val) volatile noexcept
+	{
+		return fetch_sub(val) - val;
+	}
+	
+	T* fetch_sub(ptrdiff_t val, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		return __atomic_fetch_sub(&m_value, val * sizeof(*m_value), order);
+	}
+	
+	operator T*() const volatile noexcept
+	{
+		return load();
+	}
+	
+	T* load(MemoryOrder order = memory_order_seq_cst) const volatile noexcept
+	{
+		return __atomic_load_n(&m_value, order);
+	}
+	
+	T* operator=(T* desired) volatile noexcept
+	{
+		store(desired);
+		return desired;
+	}
+	
+	void store(T* desired, MemoryOrder order = memory_order_seq_cst) volatile noexcept
+	{
+		__atomic_store_n(&m_value, desired, order);
+	}
+	
+	bool is_lock_free() const volatile noexcept
+	{
+		return __atomic_is_lock_free(sizeof(m_value), &m_value);
+	}
+};
+
+}
+
+using AK::Atomic;