Because what makes stream compaction challenging is the loop carried dependency: the location you write to in a given iteration depends on the locations you wrote to in previous iterations. By first creating a lookup table of source -> destination locations you remove the dependency. Then you can apply extremely efficient parallel methods.
Because what makes stream compaction challenging is the loop carried dependency: the location you write to in a given iteration depends on the locations you wrote to in previous iterations. By first creating a lookup table of source -> destination locations you remove the dependency. Then you can apply extremely efficient parallel methods.