atomic_xchg(3) atomic_xchg functions.

int atomic_xchg(volatile global(3clc) int *p, int val);
unsigned int atomic_xchg(volatile global(3clc) unsigned int *p, unsigned int val);
float atomic_xchg(volatile global(3clc) float *p, float val);
int atomic_xchg(volatile local(3clc) int *p, int val);
unsigned int atomic_xchg(volatile local(3clc) unsigned int *p, unsigned int val);
float atomic_xchg(volatile global(3clc) float *p, float val);


Swaps the old value stored at location p with new value given by val. The function returns old.

A 64-bit version of this function, atom_xchg(3clc), is enabled by cl_khr_int64_base_atomics(3clc).


m[blue]OpenCL Specificationm[][1]


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OpenCL Specification
page 279, section 6.12.11 - Atomic Functions for 32-bit integers