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/* PROLOG END TAG zYx                                              */
#ifndef _PPU_ATOMIC_SUB_AND_TEST_H_
#define _PPU_ATOMIC_SUB_AND_TEST_H_

#include "sync_utils.h"
#include "atomic.h"

/**
 * atomic_sub_and_test - atomically subtract and test if previous==0.
 * @v: handle to effective address of counter.
 * @a: value to be subtracted.
 *
 * Atomically subtract a value from a counter in system memory
 * and test if previous==0.  The only restriction is that @v 
 * must be word aligned.
 *
 * Returns the previous value from system memory.
 */
static __inline int _atomic_sub_and_test(int a, atomic_ea_t v)
{
  return (_atomic_modify(v, -a) == 0) ? 1 : 0;
}

#endif /* _PPU_ATOMIC_SUB_AND_TEST_H_ */