glibc/db2/mutex/x86.gcc

18 lines
416 B
Plaintext

/*
* @(#)x86.gcc 10.3 (Sleepycat) 8/27/97
*
* For gcc/x86, 0 is clear, 1 is set.
*/
#define TSL_SET(tsl) ({ \
register tsl_t *__l = (tsl); \
int __r; \
asm volatile("movl $1,%%eax; lock; xchgb %1,%%al; xorl $1,%%eax"\
: "=&a" (__r), "=m" (*__l) \
: "1" (*__l) \
); \
__r & 1; \
})
#define TSL_UNSET(tsl) (*(tsl) = 0)
#define TSL_INIT(tsl) TSL_UNSET(tsl)