From f5be479694d4dbaf59eef562d80fbeacb3bb7dc1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jo=C3=A3o=20Barbosa?= <joao.paulo.barbosa@gmail.com>
Date: Tue, 7 Jan 2020 13:47:20 +0000
Subject: [PATCH] wallet: Improve CWallet:MarkDestinationsDirty

---
 src/wallet/test/coinselector_tests.cpp | 1 +
 src/wallet/wallet.cpp                  | 5 +++--
 src/wallet/wallet.h                    | 8 ++++++++
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/wallet/test/coinselector_tests.cpp b/src/wallet/test/coinselector_tests.cpp
index 7e9f88f6b78..0e0f06c64cd 100644
--- a/src/wallet/test/coinselector_tests.cpp
+++ b/src/wallet/test/coinselector_tests.cpp
@@ -78,6 +78,7 @@ static void add_coin(CWallet& wallet, const CAmount& nValue, int nAge = 6*24, bo
     if (fIsFromMe)
     {
         wtx->m_amounts[CWalletTx::DEBIT].Set(ISMINE_SPENDABLE, 1);
+        wtx->m_is_cache_empty = false;
     }
     COutput output(wtx.get(), nInput, nAge, true /* spendable */, true /* solvable */, true /* safe */);
     vCoins.push_back(output);
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index c30125e8279..724997a36df 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -1795,6 +1795,7 @@ CAmount CWalletTx::GetCachableAmount(AmountType type, const isminefilter& filter
     auto& amount = m_amounts[type];
     if (recalculate || !amount.m_cached[filter]) {
         amount.Set(filter, type == DEBIT ? pwallet->GetDebit(*tx, filter) : pwallet->GetCredit(*tx, filter));
+        m_is_cache_empty = false;
     }
     return amount.m_value[filter];
 }
@@ -1871,6 +1872,7 @@ CAmount CWalletTx::GetAvailableCredit(bool fUseCache, const isminefilter& filter
 
     if (allow_cache) {
         m_amounts[AVAILABLE_CREDIT].Set(filter, nCredit);
+        m_is_cache_empty = false;
     }
 
     return nCredit;
@@ -3171,10 +3173,9 @@ int64_t CWallet::GetOldestKeyPoolTime()
 void CWallet::MarkDestinationsDirty(const std::set<CTxDestination>& destinations) {
     for (auto& entry : mapWallet) {
         CWalletTx& wtx = entry.second;
-
+        if (wtx.m_is_cache_empty) continue;
         for (unsigned int i = 0; i < wtx.tx->vout.size(); i++) {
             CTxDestination dst;
-
             if (ExtractDestination(wtx.tx->vout[i].scriptPubKey, dst) && destinations.count(dst)) {
                 wtx.MarkDirty();
                 break;
diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index 846a502614d..6835f33b524 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -313,6 +313,13 @@ public:
     enum AmountType { DEBIT, CREDIT, IMMATURE_CREDIT, AVAILABLE_CREDIT, AMOUNTTYPE_ENUM_ELEMENTS };
     CAmount GetCachableAmount(AmountType type, const isminefilter& filter, bool recalculate = false) const;
     mutable CachableAmount m_amounts[AMOUNTTYPE_ENUM_ELEMENTS];
+    /**
+     * This flag is true if all m_amounts caches are empty. This is particularly
+     * useful in places where MarkDirty is conditionally called and the
+     * condition can be expensive and thus can be skipped if the flag is true.
+     * See MarkDestinationsDirty.
+     */
+    mutable bool m_is_cache_empty{true};
     mutable bool fChangeCached;
     mutable bool fInMempool;
     mutable CAmount nChangeCached;
@@ -439,6 +446,7 @@ public:
         m_amounts[IMMATURE_CREDIT].Reset();
         m_amounts[AVAILABLE_CREDIT].Reset();
         fChangeCached = false;
+        m_is_cache_empty = true;
     }
 
     void BindWallet(CWallet *pwalletIn)