From 9ba1fff29e4794615c599e59ef453848a9bdb880 Mon Sep 17 00:00:00 2001
From: stickies-v <stickies-v@protonmail.com>
Date: Mon, 28 Jul 2025 13:42:13 +0100
Subject: [PATCH] kernel: refactor: ConnectTip to pass block pointer by value

By passing by value, we can remove the need to allocate a new pointer if
the callsite uses move semantics. In the process, simplify naming.
---
 src/validation.cpp | 24 +++++++++++++-----------
 src/validation.h   |  7 ++++++-
 2 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/src/validation.cpp b/src/validation.cpp
index b62691ca4c0..e339fa774f0 100644
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -3145,7 +3145,12 @@ public:
  *
  * The block is added to connectTrace if connection succeeds.
  */
-bool Chainstate::ConnectTip(BlockValidationState& state, CBlockIndex* pindexNew, const std::shared_ptr<const CBlock>& pblock, ConnectTrace& connectTrace, DisconnectedBlockTransactions& disconnectpool)
+bool Chainstate::ConnectTip(
+    BlockValidationState& state,
+    CBlockIndex* pindexNew,
+    std::shared_ptr<const CBlock> block_to_connect,
+    ConnectTrace& connectTrace,
+    DisconnectedBlockTransactions& disconnectpool)
 {
     AssertLockHeld(cs_main);
     if (m_mempool) AssertLockHeld(m_mempool->cs);
@@ -3153,18 +3158,15 @@ bool Chainstate::ConnectTip(BlockValidationState& state, CBlockIndex* pindexNew,
     assert(pindexNew->pprev == m_chain.Tip());
     // Read block from disk.
     const auto time_1{SteadyClock::now()};
-    std::shared_ptr<const CBlock> pthisBlock;
-    if (!pblock) {
+    if (!block_to_connect) {
         std::shared_ptr<CBlock> pblockNew = std::make_shared<CBlock>();
         if (!m_blockman.ReadBlock(*pblockNew, *pindexNew)) {
             return FatalError(m_chainman.GetNotifications(), state, _("Failed to read block."));
         }
-        pthisBlock = pblockNew;
+        block_to_connect = std::move(pblockNew);
     } else {
         LogDebug(BCLog::BENCH, "  - Using cached block\n");
-        pthisBlock = pblock;
     }
-    const CBlock& blockConnecting = *pthisBlock;
     // Apply the block atomically to the chain state.
     const auto time_2{SteadyClock::now()};
     SteadyClock::time_point time_3;
@@ -3174,9 +3176,9 @@ bool Chainstate::ConnectTip(BlockValidationState& state, CBlockIndex* pindexNew,
              Ticks<MillisecondsDouble>(time_2 - time_1));
     {
         CCoinsViewCache view(&CoinsTip());
-        bool rv = ConnectBlock(blockConnecting, state, pindexNew, view);
+        bool rv = ConnectBlock(*block_to_connect, state, pindexNew, view);
         if (m_chainman.m_options.signals) {
-            m_chainman.m_options.signals->BlockChecked(blockConnecting, state);
+            m_chainman.m_options.signals->BlockChecked(*block_to_connect, state);
         }
         if (!rv) {
             if (state.IsInvalid())
@@ -3212,8 +3214,8 @@ bool Chainstate::ConnectTip(BlockValidationState& state, CBlockIndex* pindexNew,
              Ticks<MillisecondsDouble>(m_chainman.time_chainstate) / m_chainman.num_blocks_total);
     // Remove conflicting transactions from the mempool.;
     if (m_mempool) {
-        m_mempool->removeForBlock(blockConnecting.vtx, pindexNew->nHeight);
-        disconnectpool.removeForBlock(blockConnecting.vtx);
+        m_mempool->removeForBlock(block_to_connect->vtx, pindexNew->nHeight);
+        disconnectpool.removeForBlock(block_to_connect->vtx);
     }
     // Update m_chain & related variables.
     m_chain.SetTip(*pindexNew);
@@ -3239,7 +3241,7 @@ bool Chainstate::ConnectTip(BlockValidationState& state, CBlockIndex* pindexNew,
         m_chainman.MaybeCompleteSnapshotValidation();
     }
 
-    connectTrace.BlockConnected(pindexNew, std::move(pthisBlock));
+    connectTrace.BlockConnected(pindexNew, std::move(block_to_connect));
     return true;
 }
 
diff --git a/src/validation.h b/src/validation.h
index c25dd2de2d9..acdd53cc2a2 100644
--- a/src/validation.h
+++ b/src/validation.h
@@ -787,7 +787,12 @@ public:
 
 protected:
     bool ActivateBestChainStep(BlockValidationState& state, CBlockIndex* pindexMostWork, const std::shared_ptr<const CBlock>& pblock, bool& fInvalidFound, ConnectTrace& connectTrace) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_mempool->cs);
-    bool ConnectTip(BlockValidationState& state, CBlockIndex* pindexNew, const std::shared_ptr<const CBlock>& pblock, ConnectTrace& connectTrace, DisconnectedBlockTransactions& disconnectpool) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_mempool->cs);
+    bool ConnectTip(
+        BlockValidationState& state,
+        CBlockIndex* pindexNew,
+        std::shared_ptr<const CBlock> block_to_connect,
+        ConnectTrace& connectTrace,
+        DisconnectedBlockTransactions& disconnectpool) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_mempool->cs);
 
     void InvalidBlockFound(CBlockIndex* pindex, const BlockValidationState& state) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
     CBlockIndex* FindMostWorkChain() EXCLUSIVE_LOCKS_REQUIRED(cs_main);