atomicCompSwap — perform an atomic compare-exchange operation to a variable
| ||inout int mem,|
|uint data |
| ||inout uint mem,|
|uint data |
The variable to use as the target of the operation.
The data to be compared and potentially exchanged with
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.
|OpenGL ES Shading Language Version|
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