Here's a short CUDA demo from NVidia, of adding two arrays of a million numbers each, elementwise. The line that actually does the add is

     add<<<1, 1>>>(N, x, y);

All N adds are conceptually done in parallel, with no side effects. In practice, hundreds or thousands of adds are done simultaneously, depending on the available hardware.

This is true branchless programming.

[1] https://developer.nvidia.com/blog/even-easier-introduction-c...