atomicAdd — perform an atomic addition to a variable
int atomicAdd(inout int mem, int data);
uint atomicAdd(inout uint mem, uint data);
atomicAdd performs an atomic addition of data to the contents of
mem and returns the original contents of mem
from before the addition occured. 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.
| Function | Version 1.10 | Version 1.20 | Version 1.30 | Version 1.40 | Version 1.50 | Version 3.30 | Version 4.00 | Version 4.10 | Version 4.20 | Version 4.30 |
|---|---|---|---|---|---|---|---|---|---|---|
| atomicAdd | - | - | - | - | - | - | - | - | - | Y |
Copyright © 2011-2012 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/.