8.2.23 _gfortran_caf_atomic_op — Atomic operation

Description:

Apply an operation atomically to an atomic integer or logical variable. After the operation, old contains the value just before the operation, which, respectively, adds (GFC_CAF_ATOMIC_ADD) atomically the value to the atomic integer variable or does a bitwise AND, OR or exclusive OR of the between the atomic variable and value; the result is then stored in the atomic variable.

Syntax:

void _gfortran_caf_atomic_op (int op, caf_token_t token, size_t offset, int image_index, void *value, void *old, int *stat, int type, int kind)

Arguments:

op	the operation to be performed; possible values GFC_CAF_ATOMIC_ADD (1), GFC_CAF_ATOMIC_AND (2), GFC_CAF_ATOMIC_OR (3), GFC_CAF_ATOMIC_XOR (4).
token	intent(in) An opaque pointer identifying the coarray.
offset	By which amount of bytes the actual data is shifted compared to the base address of the coarray.
image_index	The ID of the remote image; must be a positive number; zero indicates the current image when used noncoindexed.
old	intent(out) the value which the atomic variable had just before the atomic operation.
val	intent(in) The new value for the atomic variable, assigned to the atomic variable, if compare equals the value of the atomic variable.
stat	intent(out) Stores the status STAT= and may be NULL.
type	the data type, i.e. BT_INTEGER (1) or BT_LOGICAL (2).
kind	The kind value (only 4; always int)