ATOMIC_FETCH_ADD — Atomic ADD operation with prior fetch#

ATOMIC_FETCH_ADD(ATOM, VALUE, OLD)#

ATOMIC_FETCH_ADD(ATOM, VALUE, OLD) atomically stores the value of ATOM in OLD and adds the value of VALUE to the variable ATOM. When STAT is present and the invocation was successful, it is assigned the value 0. If it is present and the invocation has failed, it is assigned a positive value; in particular, for a coindexed ATOM, if the remote image has stopped, it is assigned the value of ISO_FORTRAN_ENV ‘s STAT_STOPPED_IMAGE and if the remote image has failed, the value STAT_FAILED_IMAGE.

Parameters:

  • ATOM – Scalar coarray or coindexed variable of integer type with ATOMIC_INT_KIND kind. ATOMIC_LOGICAL_KIND kind.

  • VALUE – Scalar of the same type as ATOM. If the kind is different, the value is converted to the kind of ATOM.

  • OLD – Scalar of the same type and kind as ATOM.

  • STAT – (optional) Scalar default-kind integer variable.

Standard:

TS 18508 or later

Class:

Atomic subroutine

Syntax:
CALL ATOMIC_FETCH_ADD (ATOM, VALUE, old [, STAT])
Example:
program atomic
  use iso_fortran_env
  integer(atomic_int_kind) :: atom[*], old
  call atomic_add (atom[1], this_image(), old)
end program atomic
See also:

ATOMIC_DEFINE — Setting a variable atomically, ATOMIC_ADD — Atomic ADD operation, ISO_FORTRAN_ENV, ATOMIC_FETCH_AND — Atomic bitwise AND operation with prior fetch, ATOMIC_FETCH_OR — Atomic bitwise OR operation with prior fetch, ATOMIC_FETCH_XOR — Atomic bitwise XOR operation with prior fetch