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 Specification\m[]\s-2\u[1]\d\s+2
atomicFunctions(3clc), atom_xchg(3clc)
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OpenCL Specification
page 279, section 6.12.11 - Atomic Functions for 32-bit integers