diff --git a/llvm/include/llvm/MC/MCAsmInfo.h b/llvm/include/llvm/MC/MCAsmInfo.h
--- a/llvm/include/llvm/MC/MCAsmInfo.h
+++ b/llvm/include/llvm/MC/MCAsmInfo.h
@@ -196,6 +196,9 @@
   /// Defaults to false.
   bool AllowAtInName = false;
 
+  /// This is true if the assembler allows '?' characters in symbol names.
+  bool AllowQuestionInName = true;
+
   /// This is true if the assembler allows the "?" character at the start of
   /// of a string to be lexed as an AsmToken::Identifier.
   /// If the AsmLexer determines that the string can be lexed as a possible
@@ -686,6 +689,7 @@
   unsigned getAssemblerDialect() const { return AssemblerDialect; }
   bool doesAllowAtInName() const { return AllowAtInName; }
   void setAllowAtInName(bool V) { AllowAtInName = V; }
+  bool doesAllowQuestionInName() const { return AllowQuestionInName; }
   bool doesAllowQuestionAtStartOfIdentifier() const {
     return AllowQuestionAtStartOfIdentifier;
   }
diff --git a/llvm/include/llvm/MC/MCParser/MCAsmLexer.h b/llvm/include/llvm/MC/MCParser/MCAsmLexer.h
--- a/llvm/include/llvm/MC/MCParser/MCAsmLexer.h
+++ b/llvm/include/llvm/MC/MCParser/MCAsmLexer.h
@@ -47,6 +47,7 @@
   bool SkipSpace = true;
   bool AllowAtInIdentifier = false;
   bool AllowHashInIdentifier = false;
+  bool AllowQuestionInIdentifier = false;
   bool IsAtStartOfStatement = true;
   bool LexMasmHexFloats = false;
   bool LexMasmIntegers = false;
diff --git a/llvm/lib/MC/MCParser/AsmLexer.cpp b/llvm/lib/MC/MCParser/AsmLexer.cpp
--- a/llvm/lib/MC/MCParser/AsmLexer.cpp
+++ b/llvm/lib/MC/MCParser/AsmLexer.cpp
@@ -33,6 +33,7 @@
 
 AsmLexer::AsmLexer(const MCAsmInfo &MAI) : MAI(MAI) {
   AllowAtInIdentifier = !StringRef(MAI.getCommentString()).startswith("@");
+  AllowQuestionInIdentifier = MAI.doesAllowAtInName();
   LexMotorolaIntegers = MAI.shouldUseMotorolaIntegers();
 }
 
@@ -145,9 +146,11 @@
 }
 
 /// LexIdentifier: [a-zA-Z_$.@?][a-zA-Z0-9_$.@#?]*
-static bool isIdentifierChar(char C, bool AllowAt, bool AllowHash) {
-  return isAlnum(C) || C == '_' || C == '$' || C == '.' || C == '?' ||
-         (AllowAt && C == '@') || (AllowHash && C == '#');
+static bool isIdentifierChar(char C, bool AllowAt, bool AllowHash,
+                             bool AllowQuestion) {
+  return isAlnum(C) || C == '_' || C == '$' || C == '.' ||
+         (AllowAt && C == '@') || (AllowHash && C == '#') ||
+         (AllowQuestion && C == '?');
 }
 
 AsmToken AsmLexer::LexIdentifier() {
@@ -157,13 +160,14 @@
     while (isDigit(*CurPtr))
       ++CurPtr;
 
-    if (!isIdentifierChar(*CurPtr, AllowAtInIdentifier,
-                          AllowHashInIdentifier) ||
+    if (!isIdentifierChar(*CurPtr, AllowAtInIdentifier, AllowHashInIdentifier,
+                          AllowQuestionInIdentifier) ||
         *CurPtr == 'e' || *CurPtr == 'E')
       return LexFloatLiteral();
   }
 
-  while (isIdentifierChar(*CurPtr, AllowAtInIdentifier, AllowHashInIdentifier))
+  while (isIdentifierChar(*CurPtr, AllowAtInIdentifier, AllowHashInIdentifier,
+                          AllowQuestionInIdentifier))
     ++CurPtr;
 
   // Handle . as a special case.