atomic_cmpxchg

atomic_cmpxchg functions.

int atomic_cmpxchg ( volatile __global int *p ,
  int cmp,
  int val)
unsigned int atomic_cmpxchg ( volatile __global unsigned int *p ,
  unsigned int cmp,
  unsigned int val)
int atomic_cmpxchg ( volatile __local int *p ,
  int cmp,
  int val)
unsigned int atomic_cmpxchg ( volatile __local unsigned int *p ,
  unsigned int cmp,
  unsigned int val)

Description

Read the 32-bit value (referred to as old) stored at location pointed by p. Compute (old == cmp) ? val : old and store result at location pointed by p. The function returns old.

A 64-bit version of this function, atom_cmpxchg, is enabled by cl_khr_int64_base_atomics.

Specification

OpenCL Specification

Also see

Atomic Functions, atom_cmpxchg

Copyright © 2007-2013 The Khronos Group Inc. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and/or associated documentation files (the "Materials"), to deal in the Materials without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Materials, and to permit persons to whom the Materials are furnished to do so, subject to the condition that this copyright notice and permission notice shall be included in all copies or substantial portions of the Materials.