[llvm] 9a33488 - [DWARFLinker] Avoid repeated hash lookups (NFC) (#109604)

[via llvm-commits]

Author: Kazu Hirata
Date: 2024-09-23T06:42:28-07:00
New Revision: 9a3348856ced274b9c7136d6726a18ca8975dad1

URL: https://github.com/llvm/llvm-project/commit/9a3348856ced274b9c7136d6726a18ca8975dad1
DIFF: https://github.com/llvm/llvm-project/commit/9a3348856ced274b9c7136d6726a18ca8975dad1.diff

LOG: [DWARFLinker] Avoid repeated hash lookups (NFC) (#109604)

Added: 
    

Modified: 
    llvm/lib/DWARFLinker/Parallel/DWARFLinkerTypeUnit.cpp

Removed: 
    


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diff  --git a/llvm/lib/DWARFLinker/Parallel/DWARFLinkerTypeUnit.cpp b/llvm/lib/DWARFLinker/Parallel/DWARFLinkerTypeUnit.cpp
index 3030aa2c39b234..9a115ace6ce3a3 100644
--- a/llvm/lib/DWARFLinker/Parallel/DWARFLinkerTypeUnit.cpp
+++ b/llvm/lib/DWARFLinker/Parallel/DWARFLinkerTypeUnit.cpp
@@ -287,12 +287,12 @@ uint32_t TypeUnit::addFileNameIntoLinetable(StringEntry *Dir,
   }
 
   uint32_t FileIdx = 0;
-  FilenamesMapTy::iterator FileEntry = FileNamesMap.find({FileName, DirIdx});
-  if (FileEntry == FileNamesMap.end()) {
+  auto [FileEntry, Inserted] = FileNamesMap.try_emplace({FileName, DirIdx});
+  if (Inserted) {
     // We currently do not support more than UINT32_MAX files.
     assert(LineTable.Prologue.FileNames.size() < UINT32_MAX);
     FileIdx = LineTable.Prologue.FileNames.size();
-    FileNamesMap.insert({{FileName, DirIdx}, FileIdx});
+    FileEntry->second = FileIdx;
     LineTable.Prologue.FileNames.push_back(DWARFDebugLine::FileNameEntry());
     LineTable.Prologue.FileNames.back().Name = DWARFFormValue::createFromPValue(
         dwarf::DW_FORM_string, FileName->getKeyData());