Atomic_or functions.
int atomic_or(volatile global(3clc) int *p, int val); unsigned int atomic_or(volatile global(3clc) unsigned int *p, unsigned int val); int atomic_or(volatile local(3clc) int *p, int val); unsigned int atomic_or(volatile local(3clc) unsigned int *p, unsigned int val);
Read the 32-bit value (referred to as old) stored at location pointed by p. Compute (old | val) and store result at location pointed by p. The function returns old.
A 64-bit version of this function, atom_or(3clc), is enabled by cl_khr_int64_extended_atomics(3clc).
\m[blue]OpenCL Specification\m[]\s-2\u[1]\d\s+2
atomicFunctions(3clc), atom_or(3clc)
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OpenCL Specification
page 279, section 6.12.11 - Atomic Functions for 32-bit integers