diff --git a/llvm/include/llvm/MC/MCContext.h b/llvm/include/llvm/MC/MCContext.h
--- a/llvm/include/llvm/MC/MCContext.h
+++ b/llvm/include/llvm/MC/MCContext.h
@@ -506,17 +506,17 @@
   /// variable after codegen.
   ///
   /// \param Idx - The index of a local variable passed to \@llvm.localescape.
-  MCSymbol *getOrCreateFrameAllocSymbol(StringRef FuncName, unsigned Idx);
+  MCSymbol *getOrCreateFrameAllocSymbol(const Twine &FuncName, unsigned Idx);
 
-  MCSymbol *getOrCreateParentFrameOffsetSymbol(StringRef FuncName);
+  MCSymbol *getOrCreateParentFrameOffsetSymbol(const Twine &FuncName);
 
-  MCSymbol *getOrCreateLSDASymbol(StringRef FuncName);
+  MCSymbol *getOrCreateLSDASymbol(const Twine &FuncName);
 
   /// Get the symbol for \p Name, or null.
   MCSymbol *lookupSymbol(const Twine &Name) const;
 
   /// Set value for a symbol.
-  void setSymbolValue(MCStreamer &Streamer, StringRef Sym, uint64_t Val);
+  void setSymbolValue(MCStreamer &Streamer, const Twine &Sym, uint64_t Val);
 
   /// getSymbols - Get a reference for the symbol table for clients that
   /// want to, for example, iterate over all symbols. 'const' because we
@@ -664,7 +664,7 @@
   MCSectionWasm *getWasmSection(const Twine &Section, SectionKind K,
                                 unsigned Flags, const MCSymbolWasm *Group,
                                 unsigned UniqueID, const char *BeginSymName);
-  
+
   /// Get the section for the provided Section name
   MCSectionDXContainer *getDXContainerSection(StringRef Section, SectionKind K);
 
diff --git a/llvm/lib/MC/MCContext.cpp b/llvm/lib/MC/MCContext.cpp
--- a/llvm/lib/MC/MCContext.cpp
+++ b/llvm/lib/MC/MCContext.cpp
@@ -211,19 +211,19 @@
   return Sym;
 }
 
-MCSymbol *MCContext::getOrCreateFrameAllocSymbol(StringRef FuncName,
+MCSymbol *MCContext::getOrCreateFrameAllocSymbol(const Twine &FuncName,
                                                  unsigned Idx) {
-  return getOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) + FuncName +
+  return getOrCreateSymbol(MAI->getPrivateGlobalPrefix() + FuncName +
                            "$frame_escape_" + Twine(Idx));
 }
 
-MCSymbol *MCContext::getOrCreateParentFrameOffsetSymbol(StringRef FuncName) {
-  return getOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) + FuncName +
+MCSymbol *MCContext::getOrCreateParentFrameOffsetSymbol(const Twine &FuncName) {
+  return getOrCreateSymbol(MAI->getPrivateGlobalPrefix() + FuncName +
                            "$parent_frame_offset");
 }
 
-MCSymbol *MCContext::getOrCreateLSDASymbol(StringRef FuncName) {
-  return getOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) + "__ehtable$" +
+MCSymbol *MCContext::getOrCreateLSDASymbol(const Twine &FuncName) {
+  return getOrCreateSymbol(MAI->getPrivateGlobalPrefix() + "__ehtable$" +
                            FuncName);
 }
 
@@ -259,8 +259,8 @@
     return new (Name, *this)
         MCSymbol(MCSymbol::SymbolKindUnset, Name, IsTemporary);
   }
-  return new (Name, *this) MCSymbol(MCSymbol::SymbolKindUnset, Name,
-                                    IsTemporary);
+  return new (Name, *this)
+      MCSymbol(MCSymbol::SymbolKindUnset, Name, IsTemporary);
 }
 
 MCSymbol *MCContext::createSymbol(StringRef Name, bool AlwaysAddSuffix,
@@ -362,9 +362,8 @@
   return Symbols.lookup(NameRef);
 }
 
-void MCContext::setSymbolValue(MCStreamer &Streamer,
-                              StringRef Sym,
-                              uint64_t Val) {
+void MCContext::setSymbolValue(MCStreamer &Streamer, const Twine &Sym,
+                               uint64_t Val) {
   auto Symbol = getOrCreateSymbol(Sym);
   Streamer.emitAssignment(Symbol, MCConstantExpr::create(Val, *this));
 }
@@ -498,14 +497,13 @@
   return Ret;
 }
 
-MCSectionELF *MCContext::createELFRelSection(const Twine &Name, unsigned Type,
-                                             unsigned Flags, unsigned EntrySize,
-                                             const MCSymbolELF *Group,
-                                             const MCSectionELF *RelInfoSection) {
+MCSectionELF *
+MCContext::createELFRelSection(const Twine &Name, unsigned Type, unsigned Flags,
+                               unsigned EntrySize, const MCSymbolELF *Group,
+                               const MCSectionELF *RelInfoSection) {
   StringMap<bool>::iterator I;
   bool Inserted;
-  std::tie(I, Inserted) =
-      RelSecNames.insert(std::make_pair(Name.str(), true));
+  std::tie(I, Inserted) = RelSecNames.insert(std::make_pair(Name.str(), true));
 
   return createELFSectionImpl(
       I->getKey(), Type, Flags, SectionKind::getReadOnly(), EntrySize, Group,
@@ -669,7 +667,6 @@
     COMDATSymName = COMDATSymbol->getName();
   }
 
-
   // Do the lookup, if we have a hit, return it.
   COFFSectionKey T{Section, COMDATSymName, Selection, UniqueID};
   auto IterBool = COFFUniquingMap.insert(std::make_pair(T, nullptr));