8.2.28. _gfortran_caf_co_reduce

8.2.28 _gfortran_caf_co_reduce — Generic collective reduction

Description:

Calculates the for the each array element of the variable a the reduction value for that element in the current team; if result_image has the value 0, the result shall be stored on all images, otherwise, only on the specified image. The opr is a pure function doing a mathematically commutative and associative operation.

The opr_flags denote the following; the values are bitwise ored. GFC_CAF_BYREF (1) if the result should be returned by value; GFC_CAF_HIDDENLEN (2) whether the result and argument string lengths shall be specified as hidden argument; GFC_CAF_ARG_VALUE (4) whether the arguments shall be passed by value, GFC_CAF_ARG_DESC (8) whether the arguments shall be passed by descriptor.

Syntax:

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