qatomic_arm.h

奇趣公司比较新的qt/emd版本

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#ifndef ARM_QATOMIC_H
#define ARM_QATOMIC_H

#include <QtCore/qglobal.h>

QT_BEGIN_HEADER

extern Q_CORE_EXPORT char q_atomic_lock;

inline char q_atomic_swp(volatile char *ptr, char newval)
{
    register int ret;
    asm volatile("swpb %0,%2,[%3]"
                 : "=&r"(ret), "=m" (*ptr)
                 : "r"(newval), "r"(ptr)
                 : "cc", "memory");
    return ret;
}

inline int q_atomic_test_and_set_int(volatile int *ptr, int expected, int newval)
{
    int ret = 0;
    while (q_atomic_swp(&q_atomic_lock, ~0) != 0);
    if (*ptr == expected) {
	*ptr = newval;
	ret = 1;
    }
    q_atomic_swp(&q_atomic_lock, 0);
    return ret;
}

inline int q_atomic_test_and_set_acquire_int(volatile int *ptr, int expected, int newval)
{
    return q_atomic_test_and_set_int(ptr, expected, newval);
}

inline int q_atomic_test_and_set_release_int(volatile int *ptr, int expected, int newval)
{
    return q_atomic_test_and_set_int(ptr, expected, newval);
}

inline int q_atomic_test_and_set_ptr(volatile void *ptr, void *expected, void *newval)
{
    int ret = 0;
    while (q_atomic_swp(&q_atomic_lock, ~0) != 0) ;
    if (*reinterpret_cast<void * volatile *>(ptr) == expected) {
	*reinterpret_cast<void * volatile *>(ptr) = newval;
	ret = 1;
    }
    q_atomic_swp(&q_atomic_lock, 0);
    return ret;
}

inline int q_atomic_increment(volatile int *ptr)
{
    while (q_atomic_swp(&q_atomic_lock, ~0) != 0) ;
    int originalValue = *ptr;
    *ptr = originalValue + 1;
    q_atomic_swp(&q_atomic_lock, 0);
    return originalValue != -1;
}

inline int q_atomic_decrement(volatile int *ptr)
{
    while (q_atomic_swp(&q_atomic_lock, ~0) != 0) ;
    int originalValue = *ptr;
    *ptr = originalValue - 1;
    q_atomic_swp(&q_atomic_lock, 0);
    return originalValue != 1;
}

inline int q_atomic_set_int(volatile int *ptr, int newval)
{
    while (q_atomic_swp(&q_atomic_lock, ~0) != 0) ;
    int originalValue = *ptr;
    *ptr = newval;
    q_atomic_swp(&q_atomic_lock, 0);
    return originalValue;
}

inline void *q_atomic_set_ptr(volatile void *ptr, void *newval)
{
    while (q_atomic_swp(&q_atomic_lock, ~0) != 0) ;
    void *originalValue = *reinterpret_cast<void * volatile *>(ptr);
    *reinterpret_cast<void * volatile *>(ptr) = newval;
    q_atomic_swp(&q_atomic_lock, 0);
    return originalValue;
}

inline int q_atomic_fetch_and_add_int(volatile int *ptr, int value)
{
    while (q_atomic_swp(&q_atomic_lock, ~0) != 0) ;
    int originalValue = *ptr;
    *ptr += value;
    q_atomic_swp(&q_atomic_lock, 0);
    return originalValue;
}

inline int q_atomic_fetch_and_add_acquire_int(volatile int *ptr, int value)
{
    return q_atomic_fetch_and_add_int(ptr, value);
}

inline int q_atomic_fetch_and_add_release_int(volatile int *ptr, int value)
{
    return q_atomic_fetch_and_add_int(ptr, value);
}

QT_END_HEADER

#endif // ARM_QATOMIC_H