[llvm] [MC] Eliminate two symbol-related hash maps (PR #95464)

[Fangrui Song via llvm-commits]

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@@ -228,7 +226,11 @@ MCSymbol *MCContext::getOrCreateLSDASymbol(const Twine &FuncName) {
                            FuncName);
 }
 
-MCSymbol *MCContext::createSymbolImpl(const StringMapEntry<bool> *Name,
+MCSymbolTableEntry &MCContext::getSymbolTableEntry(StringRef Name) {
+  return *Symbols.insert(std::make_pair(Name, MCSymbolTableValue{})).first;
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MaskRay wrote:

Perhaps `try_emplace(Name, MCSymbolTableValue{})`

https://github.com/llvm/llvm-project/pull/95464