• 2019 Update 4
  • 03/20/2019
  • Public Content
Contents

Perform Initialization in a Separate Task

Consider the following code snippet:
__kernel void something(const __global int* data) { int tid = get_global_id(0); if (0 == tid) { //Do some one-shot work } barrier(CLK_GLOBAL_MEM_FENCE); //Regular kernel code }
In this example, all work-items encounter the first branch, while the branch is relevant to only one of them. A better solution is to move the initialization phase outside the kernel code, either to a separate kernel, or to the host code.
If you need to run some kernel only once (for a single work-item), use
clEnqueueTask
, which is specially crafted for this purpose.

Product and Performance Information

1

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Notice revision #20110804