[DebugInfo] Use heterogenous lookups with std::map (NFC) (#113118)

Author: kazutakahirata

llvm/include/llvm/DebugInfo/LogicalView/Readers/LVBinaryReader.h

@@ -47,7 +47,7 @@ struct LVSymbolTableEntry final {
 
 // Function names extracted from the object symbol table.
 class LVSymbolTable final {
-  using LVSymbolNames = std::map<std::string, LVSymbolTableEntry>;
+  using LVSymbolNames = std::map<std::string, LVSymbolTableEntry, std::less<>>;
   LVSymbolNames SymbolNames;
 
 public:

llvm/lib/DebugInfo/LogicalView/Readers/LVBinaryReader.cpp

@@ -87,20 +87,20 @@ LVSectionIndex LVSymbolTable::update(LVScope *Function) {
 
 const LVSymbolTableEntry &LVSymbolTable::getEntry(StringRef Name) {
   static LVSymbolTableEntry Empty = LVSymbolTableEntry();
-  LVSymbolNames::iterator Iter = SymbolNames.find(std::string(Name));
+  LVSymbolNames::iterator Iter = SymbolNames.find(Name);
   return Iter != SymbolNames.end() ? Iter->second : Empty;
 }
 LVAddress LVSymbolTable::getAddress(StringRef Name) {
-  LVSymbolNames::iterator Iter = SymbolNames.find(std::string(Name));
+  LVSymbolNames::iterator Iter = SymbolNames.find(Name);
   return Iter != SymbolNames.end() ? Iter->second.Address : 0;
 }
 LVSectionIndex LVSymbolTable::getIndex(StringRef Name) {
-  LVSymbolNames::iterator Iter = SymbolNames.find(std::string(Name));
+  LVSymbolNames::iterator Iter = SymbolNames.find(Name);
   return Iter != SymbolNames.end() ? Iter->second.SectionIndex
                                    : getReader().getDotTextSectionIndex();
 }
 bool LVSymbolTable::getIsComdat(StringRef Name) {
-  LVSymbolNames::iterator Iter = SymbolNames.find(std::string(Name));
+  LVSymbolNames::iterator Iter = SymbolNames.find(Name);
   return Iter != SymbolNames.end() ? Iter->second.IsComdat : false;
 }