Describe rationale for identity check of BigInteger values in the code.

wrandelshofer · Jun 16, 2023 · 0a5ca6a · 0a5ca6a
1 parent 6bb73c2
commit 0a5ca6a
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/...java/ch.randelshofer.fastdoubleparser/ch/randelshofer/fastdoubleparser/FftMultiplier.java b/...java/ch.randelshofer.fastdoubleparser/ch/randelshofer/fastdoubleparser/FftMultiplier.java
@@ -539,6 +539,8 @@ static BigInteger multiply(BigInteger a, BigInteger b) {
         if (b.signum() == 0 || a.signum() == 0) {
             return BigInteger.ZERO;
         }
+        // Squaring is slightly faster than multiplication.
+        // We check for identity here and not for equality, because an equality check of big integers is very expensive.
         if (b == a) {
             return square(b);
         }