From 4755eeebbb979e0c9f3aa1030300f3551475cec6 Mon Sep 17 00:00:00 2001
From: Marco Nilsson <denravonska@gmail.com>
Date: Tue, 24 Oct 2017 13:12:46 +0200
Subject: [PATCH] Slightly more efficient mapBlockIndex usage.

Instead of counting items and then accessing, thus causing two map searches
instead of one, just use the result of a find operation instead.
---
 src/kernel.cpp | 10 ++++++----
 src/main.cpp   | 22 ++++++++++++++--------
 src/wallet.cpp |  5 +++--
 3 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/src/kernel.cpp b/src/kernel.cpp
index 37f0f77e7d..6148eba2fc 100644
--- a/src/kernel.cpp
+++ b/src/kernel.cpp
@@ -76,9 +76,10 @@ static bool SelectBlockFromCandidates(vector<pair<int64_t, uint256> >& vSortedBy
     *pindexSelected = (const CBlockIndex*) 0;
     for (auto const& item : vSortedByTimestamp)
     {
-        if (!mapBlockIndex.count(item.second))
+        const auto mapItem = mapBlockIndex.find(item.second);
+        if (mapItem == mapBlockIndex.end())
             return error("SelectBlockFromCandidates: failed to find block index for candidate block %s", item.second.ToString().c_str());
-        const CBlockIndex* pindex = mapBlockIndex[item.second];
+        const CBlockIndex* pindex = mapItem->second;
         if (fSelected && pindex->GetBlockTime() > nSelectionIntervalStop)
             break;
         if (mapSelectedBlocks.count(pindex->GetBlockHash()) > 0)
@@ -224,9 +225,10 @@ bool ComputeNextStakeModifier(const CBlockIndex* pindexPrev, uint64_t& nStakeMod
 static bool GetKernelStakeModifier(uint256 hashBlockFrom, uint64_t& nStakeModifier, int& nStakeModifierHeight, int64_t& nStakeModifierTime, bool fPrintProofOfStake)
 {
     nStakeModifier = 0;
-    if (!mapBlockIndex.count(hashBlockFrom))
+    const auto mapItem = mapBlockIndex.find(hashBlockFrom);
+    if (mapItem == mapBlockIndex.end())
         return error("GetKernelStakeModifier() : block not indexed");
-    const CBlockIndex* pindexFrom = mapBlockIndex[hashBlockFrom];
+    const CBlockIndex* pindexFrom = mapItem->second;
     nStakeModifierHeight = pindexFrom->nHeight;
     nStakeModifierTime = pindexFrom->GetBlockTime();
     int64_t nStakeModifierSelectionInterval = GetStakeModifierSelectionInterval();
diff --git a/src/main.cpp b/src/main.cpp
index bc9b6a6fbf..ebcf3fd061 100755
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -3436,14 +3436,15 @@ bool ForceReorganizeToHash(uint256 NewHash)
 {
     CTxDB txdb;
 
-    if(!mapBlockIndex.count(NewHash))
+    auto mapItem = mapBlockIndex.find(NewHash);
+    if(mapItem == mapBlockIndex.end())
         return error("ForceReorganizeToHash: failed to find requested block in block index");
 
     CBlockIndex* pindexCur = pindexBest;
-    CBlockIndex* pindexNew = mapBlockIndex[NewHash];
+    CBlockIndex* pindexNew = mapItem->second;
     printf("\r\n** Force Reorganize **\r\n");
-    printf(" Current best height %f hash %s\n",(double)pindexCur->nHeight,pindexCur->GetBlockHash().GetHex().c_str());
-    printf(" Target height %f hash %s\n",(double)pindexNew->nHeight,pindexNew->GetBlockHash().GetHex().c_str());
+    printf(" Current best height %i hash %s\n", pindexCur->nHeight,pindexCur->GetBlockHash().GetHex().c_str());
+    printf(" Target height %i hash %s\n", pindexNew->nHeight,pindexNew->GetBlockHash().GetHex().c_str());
 
     CBlock blockNew;
     if (!blockNew.ReadFromDisk(pindexNew))
@@ -5224,11 +5225,12 @@ StructCPID GetLifetimeCPID(const std::string& cpid, const std::string& sCalledFr
         if (fDebug10) printf("GetLifetimeCPID: trying %s\n",uHash.GetHex().c_str());
 
         // Ensure that we have this block.
-        if (mapBlockIndex.count(uHash) == 0)
+        auto mapItem = mapBlockIndex.find(uHash);
+        if (mapItem == mapBlockIndex.end())
            continue;
         
         // Ensure that the block is valid
-        CBlockIndex* pblockindex = mapBlockIndex[uHash];
+        CBlockIndex* pblockindex = mapItem->second;
         if(pblockindex == NULL ||
            pblockindex->IsInMainChain() == false ||
            pblockindex->GetCPID() != cpid)
@@ -8355,8 +8357,12 @@ CBlockIndex* GetHistoricalMagnitude(std::string cpid)
     if (!stCPID.BlockHash.empty())
     {
         uint256 hash(stCPID.BlockHash);
-        if (mapBlockIndex.count(hash) == 0) return pindexGenesisBlock;
-        CBlockIndex* pblockindex = mapBlockIndex[hash];
+
+        auto mapItem = mapBlockIndex.find(hash);
+        if (mapItem == mapBlockIndex.end())
+            return pindexGenesisBlock;
+
+        CBlockIndex* pblockindex = mapItem->second;
         if(!pblockindex->pnext)
             printf("GetHistoricalMagnitude: WARNING index {%s %d} for cpid %s, "
             "has no next pointer (not n main chain)\n",pblockindex->GetBlockHash().GetHex().c_str(),
diff --git a/src/wallet.cpp b/src/wallet.cpp
index 926e6a4f60..aac1c108b2 100644
--- a/src/wallet.cpp
+++ b/src/wallet.cpp
@@ -463,7 +463,8 @@ bool CWallet::AddToWallet(const CWalletTx& wtxIn)
             wtx.nTimeSmart = wtx.nTimeReceived;
             if (wtxIn.hashBlock != 0)
             {
-                if (mapBlockIndex.count(wtxIn.hashBlock))
+                auto mapItem = mapBlockIndex.find(wtxIn.hashBlock);
+                if (mapItem != mapBlockIndex.end())
                 {
                     unsigned int latestNow = wtx.nTimeReceived;
                     unsigned int latestEntry = 0;
@@ -497,7 +498,7 @@ bool CWallet::AddToWallet(const CWalletTx& wtxIn)
                         }
                     }
 
-                    unsigned int& blocktime = mapBlockIndex[wtxIn.hashBlock]->nTime;
+                    unsigned int& blocktime = mapItem->second->nTime;
                     wtx.nTimeSmart = std::max(latestEntry, std::min(blocktime, latestNow));
                 }
                 else