ATOMICCOMPSWAP(3G)              [FIXME: manual]             ATOMICCOMPSWAP(3G)

NAME
       atomicCompSwap - perform an atomic compare-exchange operation to a
       variable

DECLARATION
       int atomicCompSwap(inout int mem, uint compare, uint data);

       uint atomicCompSwap(inout uint mem, uint compare, uint data);

PARAMETERS
       mem
           The variable to use as the target of the operation.

       data
           The data to be compared and potentially exchanged with mem.

DESCRIPTION
       atomicCompSwap performs an atomic comparison of compare with the
       contents of mem. If the content of mem is equal to compare, then the
       content of data is written into mem, otherwise the content of mem is
       unmodifed. The function returns the original content of mem regardless
       of the outcome of the comparison. The contents of the memory being
       updated by the atomic operation are guaranteed not to be modified by
       any other assignment or atomic memory function in any shader invocation
       between the time the original value is read and the time the new value
       is written.

       Atomic memory functions are supported only for a limited set of
       variables. A shader will fail to compile if the value passed to the mem
       argument of an atomic memory function does not correspond to a buffer
       or shared variable. It is acceptable to pass an element of an array or
       a single component of a vector to the mem argument of an atomic memory
       function, as long as the underlying array or vector is a buffer or
       shared variable.

VERSION SUPPORT

       +---------------+-----------------------------------------------------------------------------------+
       |               |                          OpenGL Shading Language Version                          |
       +---------------+------+------+------+------+------+------+------+------+------+------+------+------+
       |Function Name  | 1.10 | 1.20 | 1.30 | 1.40 | 1.50 | 3.30 | 4.00 | 4.10 | 4.20 | 4.30 | 4.40 | 4.50 |
       +---------------+------+------+------+------+------+------+------+------+------+------+------+------+
       |atomicCompSwap |  -   |  -   |  -   |  -   |  -   |  -   |  -   |  -   |  -   | <?>  | <?>  | <?>  |
       +---------------+------+------+------+------+------+------+------+------+------+------+------+------+

SEE ALSO
       atomicAdd(), atomicAnd(), atomicOr(), atomicXor(), atomicMin(),
       atomicMax(), atomicExchange()

COPYRIGHT
       Copyright (C) 2011-2014 Khronos Group. This material may be distributed
       subject to the terms and conditions set forth in the Open Publication
       License, v 1.0, 8 June 1999.  http://opencontent.org/openpub/.

COPYRIGHT
       Copyright (C) 2012-2014 Khronos Group

[FIXME: source]                   05/21/2022                ATOMICCOMPSWAP(3G)