mimalloc/include/mimalloc-atomic.h

309 lines
12 KiB
C++

/* ----------------------------------------------------------------------------
Copyright (c) 2018, Microsoft Research, Daan Leijen
This is free software; you can redistribute it and/or modify it under the
terms of the MIT license. A copy of the license can be found in the file
"LICENSE" at the root of this distribution.
-----------------------------------------------------------------------------*/
#pragma once
#ifndef MIMALLOC_ATOMIC_H
#define MIMALLOC_ATOMIC_H
// ------------------------------------------------------
// Atomics
// We need to be portable between C, C++, and MSVC.
// ------------------------------------------------------
#if defined(__cplusplus)
#include <atomic>
#define _Atomic(tp) std::atomic<tp>
#elif defined(_MSC_VER)
#define _Atomic(tp) tp
#define ATOMIC_VAR_INIT(x) x
#else
#include <stdatomic.h>
#endif
// ------------------------------------------------------
// Atomic operations specialized for mimalloc
// ------------------------------------------------------
// Atomically add a value; returns the previous value. Memory ordering is acquire-release.
static inline uintptr_t mi_atomic_add(_Atomic(uintptr_t)* p, uintptr_t add);
// Atomically "and" a value; returns the previous value. Memory ordering is acquire-release.
static inline uintptr_t mi_atomic_and(_Atomic(uintptr_t)* p, uintptr_t x);
// Atomically "or" a value; returns the previous value. Memory ordering is acquire-release.
static inline uintptr_t mi_atomic_or(_Atomic(uintptr_t)* p, uintptr_t x);
// Atomically compare and exchange a value; returns `true` if successful.
// May fail spuriously. Memory ordering is acquire-release; with acquire on failure.
static inline bool mi_atomic_cas_weak(_Atomic(uintptr_t)* p, uintptr_t* expected, uintptr_t desired);
// Atomically compare and exchange a value; returns `true` if successful.
// Memory ordering is acquire-release; with acquire on failure.
static inline bool mi_atomic_cas_strong(_Atomic(uintptr_t)* p, uintptr_t* expected, uintptr_t desired);
// Atomically exchange a value. Memory ordering is acquire-release.
static inline uintptr_t mi_atomic_exchange(_Atomic(uintptr_t)* p, uintptr_t exchange);
// Atomically read a value. Memory ordering is relaxed.
static inline uintptr_t mi_atomic_read_relaxed(const _Atomic(uintptr_t)* p);
// Atomically read a value. Memory ordering is acquire.
static inline uintptr_t mi_atomic_read(const _Atomic(uintptr_t)* p);
// Atomically write a value. Memory ordering is release.
static inline void mi_atomic_write(_Atomic(uintptr_t)* p, uintptr_t x);
// Yield
static inline void mi_atomic_yield(void);
// Atomically add a 64-bit value; returns the previous value. Memory ordering is relaxed.
// Note: not using _Atomic(int64_t) as it is only used for statistics.
static inline int64_t mi_atomic_addi64_relaxed(volatile int64_t* p, int64_t add);
// Atomically update `*p` with the maximum of `*p` and `x` as a 64-bit value.
// Returns the previous value. Note: not using _Atomic(int64_t) as it is only used for statistics.
static inline void mi_atomic_maxi64_relaxed(volatile int64_t* p, int64_t x);
// Atomically subtract a value; returns the previous value.
static inline uintptr_t mi_atomic_sub(_Atomic(uintptr_t)* p, uintptr_t sub) {
return mi_atomic_add(p, (uintptr_t)(-((intptr_t)sub)));
}
// Atomically increment a value; returns the incremented result.
static inline uintptr_t mi_atomic_increment(_Atomic(uintptr_t)* p) {
return mi_atomic_add(p, 1);
}
// Atomically decrement a value; returns the decremented result.
static inline uintptr_t mi_atomic_decrement(_Atomic(uintptr_t)* p) {
return mi_atomic_sub(p, 1);
}
// Atomically add a signed value; returns the previous value.
static inline intptr_t mi_atomic_addi(_Atomic(intptr_t)* p, intptr_t add) {
return (intptr_t)mi_atomic_add((_Atomic(uintptr_t)*)p, (uintptr_t)add);
}
// Atomically subtract a signed value; returns the previous value.
static inline intptr_t mi_atomic_subi(_Atomic(intptr_t)* p, intptr_t sub) {
return (intptr_t)mi_atomic_addi(p,-sub);
}
// Atomically compare and exchange a void pointer; returns `true` if successful. May fail spuriously.
// Memory order is release. (like a write)
static inline bool mi_atomic_cas_weak_voidp(_Atomic(void*)* p, void** expected, void* desired, void* unused1, void* unused2) {
(void)unused1; (void)unused2; // for extra type check
return mi_atomic_cas_weak((_Atomic(uintptr_t)*)p, (uintptr_t*)expected, (uintptr_t)desired);
}
// Atomically read a void pointer; Memory order is relaxed (i.e. no fence, only atomic).
static inline void* mi_atomic_read_voidp(const _Atomic(void*)* p, void* unused) {
(void)unused; // for extra type check
return (void*)mi_atomic_read((const _Atomic(uintptr_t)*) p);
}
// Atomically read a void pointer; Memory order is acquire.
static inline void* mi_atomic_read_voidp_relaxed(const _Atomic(void*)*p, void* unused) {
(void)unused; // for extra type check
return (void*)mi_atomic_read_relaxed((const _Atomic(uintptr_t)*) p);
}
// Atomically write a void pointer; Memory order is acquire.
static inline void mi_atomic_write_voidp(_Atomic(void*)* p, void* exchange, void* unused) {
(void)unused; // for extra type check
mi_atomic_write((_Atomic(uintptr_t)*) p, (uintptr_t)exchange);
}
// Atomically exchange a void pointer; Memory order is release-acquire.
static inline void* mi_atomic_exchange_voidp(_Atomic(void*)*p, void* exchange, void* unused) {
(void)unused; // for extra type check
return (void*)mi_atomic_exchange((_Atomic(uintptr_t)*) p, (uintptr_t)exchange);
}
// Atomically compare and exchange a pointer; returns `true` if successful. May fail spuriously.
// Memory order is release. (like a write)
#define mi_atomic_cas_ptr_weak(T,p,expected,desired) \
mi_atomic_cas_weak_voidp((_Atomic(void*)*)(p), (void**)(expected), desired, *(p), *(expected))
// Atomically read a pointer; Memory order is relaxed (i.e. no fence, only atomic).
#define mi_atomic_read_ptr_relaxed(T,p) \
(T*)(mi_atomic_read_voidp_relaxed((const _Atomic(void*)*)(p), *(p)))
// Atomically read a pointer; Memory order is acquire.
#define mi_atomic_read_ptr(T,p) \
(T*)(mi_atomic_read_voidp((const _Atomic(void*)*)(p), *(p)))
// Atomically write a pointer; Memory order is acquire.
#define mi_atomic_write_ptr(T,p,x) \
mi_atomic_write_voidp((_Atomic(void*)*)(p), x, *(p))
// Atomically exchange a pointer value.
#define mi_atomic_exchange_ptr(T,p,exchange) \
(T*)(mi_atomic_exchange_voidp((_Atomic(void*)*)(p), exchange, *(p)))
#if !defined(__cplusplus) && defined(_MSC_VER)
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <intrin.h>
#ifdef _WIN64
typedef LONG64 msc_intptr_t;
#define MI_64(f) f##64
#else
typedef LONG msc_intptr_t;
#define MI_64(f) f
#endif
static inline uintptr_t mi_atomic_add(_Atomic(uintptr_t)* p, uintptr_t add) {
return (uintptr_t)MI_64(_InterlockedExchangeAdd)((volatile msc_intptr_t*)p, (msc_intptr_t)add);
}
static inline uintptr_t mi_atomic_and(_Atomic(uintptr_t)* p, uintptr_t x) {
return (uintptr_t)MI_64(_InterlockedAnd)((volatile msc_intptr_t*)p, (msc_intptr_t)x);
}
static inline uintptr_t mi_atomic_or(_Atomic(uintptr_t)* p, uintptr_t x) {
return (uintptr_t)MI_64(_InterlockedOr)((volatile msc_intptr_t*)p, (msc_intptr_t)x);
}
static inline bool mi_atomic_cas_strong(_Atomic(uintptr_t)* p, uintptr_t* expected, uintptr_t desired) {
uintptr_t read = (uintptr_t)MI_64(_InterlockedCompareExchange)((volatile msc_intptr_t*)p, (msc_intptr_t)desired, (msc_intptr_t)(*expected));
if (read == *expected) {
return true;
}
else {
*expected = read;
return false;
}
}
static inline bool mi_atomic_cas_weak(_Atomic(uintptr_t)* p, uintptr_t* expected, uintptr_t desired) {
return mi_atomic_cas_strong(p,expected,desired);
}
static inline uintptr_t mi_atomic_exchange(_Atomic(uintptr_t)* p, uintptr_t exchange) {
return (uintptr_t)MI_64(_InterlockedExchange)((volatile msc_intptr_t*)p, (msc_intptr_t)exchange);
}
static inline uintptr_t mi_atomic_read(_Atomic(uintptr_t) const* p) {
return *p;
}
static inline uintptr_t mi_atomic_read_relaxed(_Atomic(uintptr_t) const* p) {
return *p;
}
static inline void mi_atomic_write(_Atomic(uintptr_t)* p, uintptr_t x) {
#if defined(_M_IX86) || defined(_M_X64)
*p = x;
#else
mi_atomic_exchange(p,x);
#endif
}
static inline int64_t mi_atomic_addi64_relaxed(volatile _Atomic(int64_t)* p, int64_t add) {
#ifdef _WIN64
return (int64_t)mi_atomic_addi((int64_t*)p,add);
#else
int64_t current;
int64_t sum;
do {
current = *p;
sum = current + add;
} while (_InterlockedCompareExchange64(p, sum, current) != current);
return current;
#endif
}
static inline void mi_atomic_maxi64_relaxed(volatile _Atomic(int64_t)*p, int64_t x) {
int64_t current;
do {
current = *p;
} while (current < x && _InterlockedCompareExchange64(p, x, current) != current);
}
#else
#ifdef __cplusplus
#define MI_USING_STD using namespace std;
#else
#define MI_USING_STD
#endif
static inline uintptr_t mi_atomic_add(_Atomic(uintptr_t)* p, uintptr_t add) {
MI_USING_STD
return atomic_fetch_add_explicit(p, add, memory_order_acq_rel);
}
static inline uintptr_t mi_atomic_and(_Atomic(uintptr_t)* p, uintptr_t x) {
MI_USING_STD
return atomic_fetch_and_explicit(p, x, memory_order_acq_rel);
}
static inline uintptr_t mi_atomic_or(_Atomic(uintptr_t)* p, uintptr_t x) {
MI_USING_STD
return atomic_fetch_or_explicit(p, x, memory_order_acq_rel);
}
static inline bool mi_atomic_cas_weak(_Atomic(uintptr_t)* p, uintptr_t* expected, uintptr_t desired) {
MI_USING_STD
return atomic_compare_exchange_weak_explicit(p, expected, desired, memory_order_acq_rel, memory_order_acquire);
}
static inline bool mi_atomic_cas_strong(_Atomic(uintptr_t)* p, uintptr_t* expected, uintptr_t desired) {
MI_USING_STD
return atomic_compare_exchange_strong_explicit(p, expected, desired, memory_order_acq_rel, memory_order_acquire);
}
static inline uintptr_t mi_atomic_exchange(_Atomic(uintptr_t)* p, uintptr_t exchange) {
MI_USING_STD
return atomic_exchange_explicit(p, exchange, memory_order_acq_rel);
}
static inline uintptr_t mi_atomic_read_relaxed(const _Atomic(uintptr_t)* p) {
MI_USING_STD
return atomic_load_explicit((_Atomic(uintptr_t)*) p, memory_order_relaxed);
}
static inline uintptr_t mi_atomic_read(const _Atomic(uintptr_t)* p) {
MI_USING_STD
return atomic_load_explicit((_Atomic(uintptr_t)*) p, memory_order_acquire);
}
static inline void mi_atomic_write(_Atomic(uintptr_t)* p, uintptr_t x) {
MI_USING_STD
return atomic_store_explicit(p, x, memory_order_release);
}
static inline int64_t mi_atomic_addi64_relaxed(volatile int64_t* p, int64_t add) {
MI_USING_STD
return atomic_fetch_add_explicit((_Atomic(int64_t)*)p, add, memory_order_relaxed);
}
static inline void mi_atomic_maxi64_relaxed(volatile int64_t* p, int64_t x) {
MI_USING_STD
int64_t current = atomic_load_explicit((_Atomic(int64_t)*)p, memory_order_relaxed);
while (current < x && !atomic_compare_exchange_weak_explicit((_Atomic(int64_t)*)p, &current, x, memory_order_acq_rel, memory_order_acquire)) { /* nothing */ };
}
#endif
#if defined(__cplusplus)
#include <thread>
static inline void mi_atomic_yield(void) {
std::this_thread::yield();
}
#elif defined(_WIN32)
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
static inline void mi_atomic_yield(void) {
YieldProcessor();
}
#elif (defined(__GNUC__) || defined(__clang__)) && \
(defined(__x86_64__) || defined(__i386__) || defined(__arm__) || defined(__aarch64__))
#if defined(__x86_64__) || defined(__i386__)
static inline void mi_atomic_yield(void) {
asm volatile ("pause" ::: "memory");
}
#elif defined(__arm__) || defined(__aarch64__)
static inline void mi_atomic_yield(void) {
asm volatile("yield");
}
#endif
#elif defined(__wasi__)
#include <sched.h>
static inline void mi_atomic_yield(void) {
sched_yield();
}
#else
#include <unistd.h>
static inline void mi_atomic_yield(void) {
sleep(0);
}
#endif
#endif // __MIMALLOC_ATOMIC_H