Description
Swaps the old value stored at location
p with new value given by val.
The function returns old value.
An application that wants to use this extension will need to include the #pragma
OPENCL EXTENSION cl_khr_int64_base_atomics : enable in the OpenCL program source.
This function is performed in one atomic transaction. These transactions are atomic for the device executing these atomic functions. There is no guarantee of atomicity if the atomic operations to the same memory location are being performed by kernels executing on multiple devices.
Atomic operations on 64-bit integers and 32-bit integers (and float) are also atomic with regard to each other.
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