diff --git a/xor.go b/xor.go
index a58a72f473199a023b8322fbecf8890fcf482176..852930df813dd1101584ecd1be90eccee9a29188 100644
--- a/xor.go
+++ b/xor.go
@@ -25,6 +25,9 @@ func fastXOR(key [4]byte, keyPos int, b []byte) int {
 		}
 		k := binary.LittleEndian.Uint64(alignedKey[:])
 
+		// At some point in the future we can clean these unrolled loops up.
+		// See https://github.com/golang/go/issues/31586#issuecomment-487436401
+
 		// Then we xor until b is less than 128 bytes.
 		for len(b) >= 128 {
 			v := binary.LittleEndian.Uint64(b)