Merge bitcoin/bitcoin#23693: Revert "Fixes Bug in Transaction generation in ComplexMempool benchmark"

faa185b Revert "Fixes Bug in Transaction generation in ComplexMempool benchmark" (MarcoFalke)

Pull request description:

  Developers are reporting crashes (potentially OOM) on IRC, but I can't reproduce. Still, revert this for now, since one developer reported the bare metal this was running on crashed.

Top commit has no ACKs.

Tree-SHA512: 080db4fcfc682b68f4cc40dfabd9d3e0e3f6e6297ce4b782d5de2c83bc18f85f60efb1cda64c51e23c4fd2a05222a904e7a11853d9f9c052dcd26a53aa00b235

Author: MarcoFalke

src/bench/mempool_stress.cpp

@@ -51,7 +51,7 @@ static std::vector<CTransactionRef> CreateOrderedCoins(FastRandomContext& det_ra
         size_t n_ancestors = det_rand.randrange(10)+1;
         for (size_t ancestor = 0; ancestor < n_ancestors && !available_coins.empty(); ++ancestor){
             size_t idx = det_rand.randrange(available_coins.size());
-            Available& coin = available_coins[idx];
+            Available coin = available_coins[idx];
             uint256 hash = coin.ref->GetHash();
             // biased towards taking min_ancestors parents, but maybe more
             size_t n_to_take = det_rand.randrange(2) == 0 ?
@@ -63,17 +63,15 @@ static std::vector<CTransactionRef> CreateOrderedCoins(FastRandomContext& det_ra
                 tx.vin.back().scriptSig = CScript() << coin.tx_count;
                 tx.vin.back().scriptWitness.stack.push_back(CScriptNum(coin.tx_count).getvch());
             }
-            if (coin.vin_left == coin.ref->vout.size()) {
-                if(available_coins.size()-1!=idx){ // if idx is not the last index swap it with the end index
-                   std::swap(available_coins[idx], available_coins.back());
-                }
+            if (coin.vin_left == coin.ref->vin.size()) {
+                coin = available_coins.back();
                 available_coins.pop_back();
             }
-        }
-        tx.vout.resize(det_rand.randrange(10)+2);
-        for (auto& out : tx.vout) {
-            out.scriptPubKey = CScript() << CScriptNum(tx_counter) << OP_EQUAL;
-            out.nValue = 10 * COIN;
+            tx.vout.resize(det_rand.randrange(10)+2);
+            for (auto& out : tx.vout) {
+                out.scriptPubKey = CScript() << CScriptNum(tx_counter) << OP_EQUAL;
+                out.nValue = 10 * COIN;
+            }
         }
         ordered_coins.emplace_back(MakeTransactionRef(tx));
         available_coins.emplace_back(ordered_coins.back(), tx_counter++);