[llvm] [DebugInfo] Use heterogenous lookups with std::map (NFC) (PR #132354)

[Kazu Hirata via llvm-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/132354

Heterogenous lookups allow us to call find with StringRef, avoiding a
temporary heap allocation of std::string.


>From 9eb803560122cf3c0d9e40636a9da56d893981e7 Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Fri, 21 Mar 2025 01:14:18 -0700
Subject: [PATCH] [DebugInfo] Use heterogenous lookups with std::map (NFC)

Heterogenous lookups allow us to call find with StringRef, avoiding a
temporary heap allocation of std::string.
---
 llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h | 2 +-
 llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp        | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h
index f51571aa24c38..595215ba35dd5 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFVerifier.h
@@ -37,7 +37,7 @@ struct AggregationData {
 
 class OutputCategoryAggregator {
 private:
-  std::map<std::string, AggregationData> Aggregation;
+  std::map<std::string, AggregationData, std::less<>> Aggregation;
   bool IncludeDetail;
 
 public:
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
index 05bb829cf44db..69027500ab51d 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
@@ -2194,7 +2194,7 @@ void OutputCategoryAggregator::EnumerateResults(
 }
 void OutputCategoryAggregator::EnumerateDetailedResultsFor(
     StringRef category, std::function<void(StringRef, unsigned)> handleCounts) {
-  const auto Agg = Aggregation.find(std::string(category));
+  const auto Agg = Aggregation.find(category);
   if (Agg != Aggregation.end()) {
     for (const auto &[name, aggData] : Agg->second.DetailedCounts) {
       handleCounts(name, aggData);