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

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