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#include <stdbool.h>
#include <stdint.h>
#include <stddef.h>
#include "test.h"
typedef unsigned long int uint64;
typedef unsigned int uint32;
typedef struct pg_atomic_uint64
{
/* alignment guaranteed due to being on a 64bit platform */
volatile uint64 value;
} pg_atomic_uint64;
typedef struct pg_atomic_uint32
{
volatile uint32 value;
} pg_atomic_uint32;
static inline bool
pg_atomic_compare_exchange_u64_impl(volatile pg_atomic_uint64 *ptr,
uint64 *expected, uint64 newval)
{
char ret;
/*
* Perform cmpxchg and use the zero flag which it implicitly sets when
* equal to measure the success.
*/
__asm__ __volatile__(
" lock \n"
" cmpxchgq %4,%5 \n"
" setz %2 \n"
: "=a" (*expected), "=m"(ptr->value), "=q" (ret)
: "a" (*expected), "r" (newval), "m"(ptr->value)
: "memory", "cc");
ASSERT(1, ret);
return (bool) ret;
}
static inline bool
pg_atomic_compare_exchange_u32_impl(volatile pg_atomic_uint32 *ptr,
uint32 *expected, uint32 newval)
{
char ret;
/*
* Perform cmpxchg and use the zero flag which it implicitly sets when
* equal to measure the success.
*/
__asm__ __volatile__(
" lock \n"
" cmpxchgl %4,%5 \n"
" setz %2 \n"
: "=a" (*expected), "=m"(ptr->value), "=q" (ret)
: "a" (*expected), "r" (newval), "m"(ptr->value)
: "memory", "cc");
return (bool) ret;
}
int main() {
pg_atomic_uint32 a;
a.value = 10;
uint32 b = 17;
uint32 c = 0;
pg_atomic_compare_exchange_u32_impl(&a, &b, c);
ASSERT(10, a.value);
ASSERT(10, b);
ASSERT(0, c);
return 0;
}
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