Complex loop exit condition

I tested both of your suggestions:

1- inner loop with fixed limit. Now it is pipeliable, but increase in run-time, due to wasted clocks in inner loop, is large. Because my upper limit is huge.

2- I tested the ND-range. That really worked well! I don't know exactly what is the difference between implementation of pipelinging inside a task, or pipelining among work-items inside a ND-range, however, this is a good example for me that they are not similar.

Thank you very much for following this discussion. that was really instructive. :)