document algorithm

antlr · Mar 10, 2024 · c3692cc · c3692cc
1 parent 967be76
commit c3692cc
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/runtime/JavaScript/src/antlr4/misc/BitSet.js b/runtime/JavaScript/src/antlr4/misc/BitSet.js
@@ -111,6 +111,7 @@ export default class BitSet {
  }
 
  _bitCount(l) {
+ // see https://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetParallel
  let count = 0;
  l = l - ((l >> 1) & 0x55555555);
  l = (l & 0x33333333) + ((l >> 2) & 0x33333333);