Comments on hash_combine.

Author: evoskuil

include/bitcoin/system/impl/hash/functions.ipp

@@ -240,19 +240,20 @@ INLINE constexpr size_t djb2_hash(const data_slice& data) NOEXCEPT
 // Combine hash values, such as djb2_hash or unique_hash outputs.
 INLINE constexpr size_t hash_combine(size_t left, size_t right) NOEXCEPT
 {
+    //// This leads to mixing null points (850k identical) with other buckets.
     ////constexpr auto prime1 = possible_narrow_cast<size_t>(0x9e3779b97f4a7c15_u64);
     ////constexpr auto prime2 = possible_narrow_cast<size_t>(0x517cc1b727220a95_u64);
-
+    ////
     ////auto first = left;
     ////first ^= shift_right(first, 23);
     ////first *= prime1;
     ////first ^= shift_right(first, 19);
-
+    ////
     ////auto second = right;
     ////second ^= shift_right(second, 13);
     ////second *= prime2;
     ////second ^= shift_right(second, 31);
-
+    ////
     ////// seed parameter, defaults to zero.
     ////first ^= second;
     ////first += seed;