[clang-tools-extra] [clang-tidy] Avoid repeated hash lookups (NFC) (PR #127444)

[Kazu Hirata via cfe-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/127444

None

>From 4dfb98f2290a1af132edd3c5658a9c35bc48c1ed Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Sun, 16 Feb 2025 08:22:46 -0800
Subject: [PATCH] [clang-tidy] Avoid repeated hash lookups (NFC)

---
 .../clang-tidy/modernize/DeprecatedHeadersCheck.cpp       | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/clang-tools-extra/clang-tidy/modernize/DeprecatedHeadersCheck.cpp b/clang-tools-extra/clang-tidy/modernize/DeprecatedHeadersCheck.cpp
index 6a467910521f5..3d3a79d8eaf21 100644
--- a/clang-tools-extra/clang-tidy/modernize/DeprecatedHeadersCheck.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/DeprecatedHeadersCheck.cpp
@@ -199,10 +199,10 @@ void IncludeModernizePPCallbacks::InclusionDirective(
   // 2. Insert `using namespace std;` to the beginning of TU.
   // 3. Do nothing and let the user deal with the migration himself.
   SourceLocation DiagLoc = FilenameRange.getBegin();
-  if (CStyledHeaderToCxx.count(FileName) != 0) {
-    IncludesToBeProcessed.emplace_back(
-        IncludeMarker{CStyledHeaderToCxx[FileName], FileName,
-                      FilenameRange.getAsRange(), DiagLoc});
+  if (auto It = CStyledHeaderToCxx.find(FileName);
+      It != CStyledHeaderToCxx.end()) {
+    IncludesToBeProcessed.emplace_back(IncludeMarker{
+        It->second, FileName, FilenameRange.getAsRange(), DiagLoc});
   } else if (DeleteHeaders.count(FileName) != 0) {
     IncludesToBeProcessed.emplace_back(
         // NOLINTNEXTLINE(modernize-use-emplace) - false-positive