Hi John, > This turned out to be a loser, but in the course of trying it a better > idea occurred to me. v8's prefix detection was really a special-case > optimization where the sort key is all non-negative integers (or all > negative, but that's not common). It's wasted work when the input is > mixed in sign, and for abbreviated keys. It's not much of a waste, but > we can do better. > > v9 computes the common prefix during every recursion at the same time > we populate the SortTuple's current byte. That should be practically > free given a modest amount of instruction-level parallelism.
+1 and v9-0001 LGTM. -- Regards, ChangAo Chen
