From 97ca7d57bcedab341e7887cd7950299d2bde9598 Mon Sep 17 00:00:00 2001 From: Vito Tumas <5780819+Tapanito@users.noreply.github.com> Date: Wed, 10 Jun 2026 13:44:57 +0200 Subject: [PATCH] perf: Dispatch "hasInvalidAmount()" on type tag instead of dynamic_cast (#7402) --- src/libxrpl/protocol/STAmount.cpp | 32 ++++++++++++++++++++++++------- 1 file changed, 25 insertions(+), 7 deletions(-) diff --git a/src/libxrpl/protocol/STAmount.cpp b/src/libxrpl/protocol/STAmount.cpp index 449efc9543..748d00f25a 100644 --- a/src/libxrpl/protocol/STAmount.cpp +++ b/src/libxrpl/protocol/STAmount.cpp @@ -1138,16 +1138,34 @@ hasInvalidAmount(STBase const& field, int depth, beast::Journal j) return true; } - if (auto const amount = dynamic_cast(&field)) - return !isLegalMPT(*amount) || !isLegalNet(*amount); + // Dispatch on the serialized type tag rather than RTTI: this is on the invariant-checking path + // and a dynamic_cast chain over every field of every modified entry is measurably expensive. + // The object-like tags below all denote STObject subclasses (STLedgerEntry, STTx), so the + // downcast is sound; nested fields are only ever plain STI_OBJECT / STI_ARRAY containers. + // safeDowncast keeps a dynamic_cast validity assert in debug builds while compiling to + // static_cast in release. + switch (field.getSType()) + { + case STI_AMOUNT: { + auto const& amount = safeDowncast(field); + return !isLegalMPT(amount) || !isLegalNet(amount); + } - if (auto const object = dynamic_cast(&field)) - return hasInvalidAmount(*object, depth + 1, j); + case STI_OBJECT: + case STI_LEDGERENTRY: + case STI_TRANSACTION: + return hasInvalidAmount(safeDowncast(field), depth + 1, j); - if (auto const array = dynamic_cast(&field)) - return hasInvalidAmount(*array, depth + 1, j); + case STI_ARRAY: + return hasInvalidAmount(safeDowncast(field), depth + 1, j); - return false; + default: { + XRPL_ASSERT( + dynamic_cast(&field) == nullptr, + "xrpl::hasInvalidAmount : unhandled STObject type"); + return false; + } + } } bool