perf: speedup of CBLSLazyPublicKey::operator== when comparing to the default / null object; speedup CDeterministicMNList::AddMN by avoiding check to IsValid when a nullcheck is sufficient

Author: PastaPastaPasta

src/bls/bls.h

@@ -391,6 +391,7 @@ class CBLSLazyWrapper
     mutable std::mutex mutex;
 
     mutable std::array<uint8_t, BLSObject::SerSize> vecBytes;
+    // Indicates if the value contained in vecBytes is valid
     mutable bool bufValid{false};
     mutable bool bufLegacyScheme{true};
 
@@ -462,7 +463,7 @@ class CBLSLazyWrapper
     {
         std::unique_lock<std::mutex> l(mutex);
         s.read(AsWritableBytes(Span{vecBytes.data(), BLSObject::SerSize}));
-        bufValid = true;
+        bufValid = std::any_of(vecBytes.begin(), vecBytes.end(), [](uint8_t c) { return c != 0; });
         bufLegacyScheme = specificLegacyScheme;
         objInitialized = false;
         hash.SetNull();
@@ -507,6 +508,14 @@ class CBLSLazyWrapper
 
     bool operator==(const CBLSLazyWrapper& r) const
     {
+        // If neither bufValid or objInitialized are set, then the object is the default object.
+        const bool is_default{bufValid || objInitialized};
+        const bool r_is_default{r.bufValid || r.objInitialized};
+        // If both are default; they are equal.
+        if (is_default && r_is_default) return true;
+        // If one is default and the other isn't, we are not equal
+        if (is_default != r_is_default) return false;
+
         if (bufValid && r.bufValid && bufLegacyScheme == r.bufLegacyScheme) {
             return vecBytes == r.vecBytes;
         }

src/evo/deterministicmns.cpp

@@ -477,7 +477,7 @@ void CDeterministicMNList::AddMN(const CDeterministicMNCPtr& dmn, bool fBumpTota
         throw(std::runtime_error(strprintf("%s: Can't add a masternode %s with a duplicate keyIDOwner=%s", __func__,
                 dmn->proTxHash.ToString(), EncodeDestination(PKHash(dmn->pdmnState->keyIDOwner)))));
     }
-    if (dmn->pdmnState->pubKeyOperator.Get().IsValid() && !AddUniqueProperty(*dmn, dmn->pdmnState->pubKeyOperator)) {
+    if (dmn->pdmnState->pubKeyOperator != CBLSLazyPublicKey() && !AddUniqueProperty(*dmn, dmn->pdmnState->pubKeyOperator)) {
         mnUniquePropertyMap = mnUniquePropertyMapSaved;
         throw(std::runtime_error(strprintf("%s: Can't add a masternode %s with a duplicate pubKeyOperator=%s", __func__,
                 dmn->proTxHash.ToString(), dmn->pdmnState->pubKeyOperator.ToString())));