1 files changed, 27 insertions, 37 deletions

diff --git a/src/kernel/coinstats.cpp b/src/kernel/coinstats.cpp
index 527433f45e..9bd755ed27 100644
--- a/src/kernel/coinstats.cpp
+++ b/src/kernel/coinstats.cpp
@@ -48,15 +48,35 @@ uint64_t GetBogoSize(const CScript& script_pub_key)
            script_pub_key.size() /* scriptPubKey */;
 }
 
-DataStream TxOutSer(const COutPoint& outpoint, const Coin& coin)
+template <typename T>
+static void TxOutSer(T& ss, const COutPoint& outpoint, const Coin& coin)
 {
-    DataStream ss{};
     ss << outpoint;
-    ss << static_cast<uint32_t>(coin.nHeight * 2 + coin.fCoinBase);
+    ss << static_cast<uint32_t>((coin.nHeight << 1) + coin.fCoinBase);
     ss << coin.out;
-    return ss;
 }
 
+static void ApplyCoinHash(HashWriter& ss, const COutPoint& outpoint, const Coin& coin)
+{
+    TxOutSer(ss, outpoint, coin);
+}
+
+void ApplyCoinHash(MuHash3072& muhash, const COutPoint& outpoint, const Coin& coin)
+{
+    DataStream ss{};
+    TxOutSer(ss, outpoint, coin);
+    muhash.Insert(MakeUCharSpan(ss));
+}
+
+void RemoveCoinHash(MuHash3072& muhash, const COutPoint& outpoint, const Coin& coin)
+{
+    DataStream ss{};
+    TxOutSer(ss, outpoint, coin);
+    muhash.Remove(MakeUCharSpan(ss));
+}
+
+static void ApplyCoinHash(std::nullptr_t, const COutPoint& outpoint, const Coin& coin) {}
+
 //! Warning: be very careful when changing this! assumeutxo and UTXO snapshot
 //! validation commitments are reliant on the hash constructed by this
 //! function.
@@ -69,32 +89,13 @@ DataStream TxOutSer(const COutPoint& outpoint, const Coin& coin)
 //! It is also possible, though very unlikely, that a change in this
 //! construction could cause a previously invalid (and potentially malicious)
 //! UTXO snapshot to be considered valid.
-static void ApplyHash(HashWriter& ss, const uint256& hash, const std::map<uint32_t, Coin>& outputs)
-{
-    for (auto it = outputs.begin(); it != outputs.end(); ++it) {
-        if (it == outputs.begin()) {
-            ss << hash;
-            ss << VARINT(it->second.nHeight * 2 + it->second.fCoinBase ? 1u : 0u);
-        }
-
-        ss << VARINT(it->first + 1);
-        ss << it->second.out.scriptPubKey;
-        ss << VARINT_MODE(it->second.out.nValue, VarIntMode::NONNEGATIVE_SIGNED);
-
-        if (it == std::prev(outputs.end())) {
-            ss << VARINT(0u);
-        }
-    }
-}
-
-static void ApplyHash(std::nullptr_t, const uint256& hash, const std::map<uint32_t, Coin>& outputs) {}
-
-static void ApplyHash(MuHash3072& muhash, const uint256& hash, const std::map<uint32_t, Coin>& outputs)
+template <typename T>
+static void ApplyHash(T& hash_obj, const uint256& hash, const std::map<uint32_t, Coin>& outputs)
 {
     for (auto it = outputs.begin(); it != outputs.end(); ++it) {
         COutPoint outpoint = COutPoint(hash, it->first);
         Coin coin = it->second;
-        muhash.Insert(MakeUCharSpan(TxOutSer(outpoint, coin)));
+        ApplyCoinHash(hash_obj, outpoint, coin);
     }
 }
 
@@ -118,8 +119,6 @@ static bool ComputeUTXOStats(CCoinsView* view, CCoinsStats& stats, T hash_obj, c
     std::unique_ptr<CCoinsViewCursor> pcursor(view->Cursor());
     assert(pcursor);
 
-    PrepareHash(hash_obj, stats);
-
     uint256 prevkey;
     std::map<uint32_t, Coin> outputs;
     while (pcursor->Valid()) {
@@ -180,15 +179,6 @@ std::optional<CCoinsStats> ComputeUTXOStats(CoinStatsHashType hash_type, CCoinsV
     return stats;
 }
 
-// The legacy hash serializes the hashBlock
-static void PrepareHash(HashWriter& ss, const CCoinsStats& stats)
-{
-    ss << stats.hashBlock;
-}
-// MuHash does not need the prepare step
-static void PrepareHash(MuHash3072& muhash, CCoinsStats& stats) {}
-static void PrepareHash(std::nullptr_t, CCoinsStats& stats) {}
-
 static void FinalizeHash(HashWriter& ss, CCoinsStats& stats)
 {
     stats.hashSerialized = ss.GetHash();