Cache transaction validation successes

src/main.cpp

@@ -1277,6 +1277,9 @@ int GetSpendHeight(const CCoinsViewCache& inputs)
     return pindexPrev->nHeight + 1;
 }
 
+static mrumap<uint256, unsigned int> cacheCheck(2 * MAX_BLOCK_SIZE / CTransaction().GetSerializeSize(SER_NETWORK, PROTOCOL_VERSION));
+static boost::mutex cs_cacheCheck;
+
 namespace Consensus {
 bool CheckTxInputs(const CTransaction& tx, CValidationState& state, const CCoinsViewCache& inputs, int nSpendHeight)
 {
@@ -1331,6 +1334,17 @@ bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsVi
 {
     if (!tx.IsCoinBase())
     {
+        if (fScriptChecks) {
+            boost::unique_lock<boost::mutex> lock(cs_cacheCheck);
+            mrumap<uint256, unsigned int>::const_iterator iter = cacheCheck.find(tx.GetHash());
+            if (iter != cacheCheck.end()) {
+                // The following test relies on the fact that all script validation flags are softforks (i.e. an extra bit set cannot cause a false result to become true).
+                if ((iter->second & flags) == flags) {
+                    return true;
+                }
+            }
+        }
+
         if (!Consensus::CheckTxInputs(tx, state, inputs, GetSpendHeight(inputs)))
             return false;
 
@@ -1381,6 +1395,11 @@ bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsVi
         }
     }
 
+    if (cacheStore && fScriptChecks && pvChecks == NULL) {
+        boost::unique_lock<boost::mutex> lock(cs_cacheCheck);
+        cacheCheck.insert(tx.GetHash(), flags);
+    }
+
     return true;
 }
 
@@ -2101,6 +2120,13 @@ bool static ConnectTip(CValidationState &state, CBlockIndex *pindexNew, CBlock *
     BOOST_FOREACH(const CTransaction &tx, pblock->vtx) {
         SyncWithWallets(tx, pblock);
     }
+    // Erase block's transactions from the validation cache
+    {
+        boost::unique_lock<boost::mutex> lock(cs_cacheCheck);
+        BOOST_FOREACH(const CTransaction &tx, pblock->vtx) {
+            cacheCheck.erase(tx.GetHash());
+        }
+    }
 
     int64_t nTime6 = GetTimeMicros(); nTimePostConnect += nTime6 - nTime5; nTimeTotal += nTime6 - nTime1;
     LogPrint("bench", "  - Connect postprocess: %.2fms [%.2fs]\n", (nTime6 - nTime5) * 0.001, nTimePostConnect * 0.000001);