From 6e267666819f5a582ae34ed960dea203a2bd90d1 Mon Sep 17 00:00:00 2001
From: Vito <5780819+Tapanito@users.noreply.github.com>
Date: Thu, 16 Jul 2026 12:28:53 +0200
Subject: [PATCH] refactor: Avoid repeated sfPaymentRemaining lookups in
 makeRegularPayment

Cache the sfPaymentRemaining proxy once instead of re-fetching it at
each of the three places it's read in the loop condition, the final-
payment assert, and the overpayment guard. It's a write-through proxy,
so it still reflects doPayment's mutations each iteration.

Also explicitly zero-initialize totalPaid so the starting baseline
isn't left implicit.
---
 src/libxrpl/ledger/helpers/LendingHelpers.cpp | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/src/libxrpl/ledger/helpers/LendingHelpers.cpp b/src/libxrpl/ledger/helpers/LendingHelpers.cpp
index 0bd3befe16..e6c3d632c1 100644
--- a/src/libxrpl/ledger/helpers/LendingHelpers.cpp
+++ b/src/libxrpl/ledger/helpers/LendingHelpers.cpp
@@ -1517,10 +1517,15 @@ makeRegularPayment(
 
     // Keep a running total of the actual parts paid
     LoanPaymentParts totalParts;
-    Number totalPaid;
+    Number totalPaid = kNumZero;
     std::size_t numPayments = 0;
 
-    while ((amount >= (totalPaid + periodic.totalDue)) && loan->at(sfPaymentRemaining) > 0 &&
+    // Cached here (rather than re-looking up loan->at(sfPaymentRemaining) at each use) since it's
+    // read multiple times below. It's a write-through proxy, so it still reflects doPayment's
+    // mutations each iteration.
+    auto paymentRemainingProxy = loan->at(sfPaymentRemaining);
+
+    while ((amount >= (totalPaid + periodic.totalDue)) && paymentRemainingProxy > 0 &&
            numPayments < kLoanMaximumPaymentsPerTransaction)
     {
         // Try to make more payments
@@ -1534,8 +1539,7 @@ makeRegularPayment(
         ++numPayments;
 
         XRPL_ASSERT_PARTS(
-            (periodic.specialCase == PaymentSpecialCase::Final) ==
-                (loan->at(sfPaymentRemaining) == 0),
+            (periodic.specialCase == PaymentSpecialCase::Final) == (paymentRemainingProxy == 0),
             "xrpl::detail::makeRegularPayment",
             "final payment is the final payment");
 
@@ -1578,9 +1582,9 @@ makeRegularPayment(
     bool const overpaymentSupported =
         paymentType == LoanPaymentType::Overpayment && loan->isFlag(lsfLoanOverpayment);
 
-    bool const overpaymentAllowed =          //
-        loan->at(sfPaymentRemaining) > 0 &&  //
-        totalPaid < roundedAmount &&         //
+    bool const overpaymentAllowed =   //
+        paymentRemainingProxy > 0 &&  //
+        totalPaid < roundedAmount &&  //
         numPayments < kLoanMaximumPaymentsPerTransaction;
 
     if (overpaymentSupported && overpaymentAllowed)