diff --git a/clang/lib/Basic/Targets/AArch64.cpp b/clang/lib/Basic/Targets/AArch64.cpp
--- a/clang/lib/Basic/Targets/AArch64.cpp
+++ b/clang/lib/Basic/Targets/AArch64.cpp
@@ -973,12 +973,16 @@
       }
     }
   for (const auto &Feature : FeaturesVec)
-    if (Feature[0] == '+') {
-      std::string F;
-      llvm::AArch64::getFeatureOption(Feature, F);
-      UpdatedFeaturesVec.push_back(F);
-    } else if (Feature[0] != '?')
-      UpdatedFeaturesVec.push_back(Feature);
+    if (Feature[0] != '?') {
+      std::string UpdatedFeature = Feature;
+      if (Feature[0] == '+') {
+        std::optional<llvm::AArch64::ExtensionInfo> Extension =
+          llvm::AArch64::parseArchExtension(Feature.substr(1));
+        if (Extension)
+          UpdatedFeature = Extension->Feature.str();
+      }
+      UpdatedFeaturesVec.push_back(UpdatedFeature);
+    }
 
   return TargetInfo::initFeatureMap(Features, Diags, CPU, UpdatedFeaturesVec);
 }
diff --git a/llvm/include/llvm/TargetParser/AArch64TargetParser.h b/llvm/include/llvm/TargetParser/AArch64TargetParser.h
--- a/llvm/include/llvm/TargetParser/AArch64TargetParser.h
+++ b/llvm/include/llvm/TargetParser/AArch64TargetParser.h
@@ -505,7 +505,6 @@
 StringRef resolveCPUAlias(StringRef CPU);
 
 // Information by Name
-void getFeatureOption(StringRef Name, std::string &Feature);
 std::optional<ArchInfo> getArchForCpu(StringRef CPU);
 
 // Parser
diff --git a/llvm/lib/TargetParser/AArch64TargetParser.cpp b/llvm/lib/TargetParser/AArch64TargetParser.cpp
--- a/llvm/lib/TargetParser/AArch64TargetParser.cpp
+++ b/llvm/lib/TargetParser/AArch64TargetParser.cpp
@@ -25,16 +25,6 @@
   return 0;
 }
 
-void AArch64::getFeatureOption(StringRef Name, std::string &Feature) {
-  for (const auto &E : llvm::AArch64::Extensions) {
-    if (Name == E.Name) {
-      Feature = E.Feature;
-      return;
-    }
-  }
-  Feature = Name.str();
-}
-
 std::optional<AArch64::ArchInfo> AArch64::getArchForCpu(StringRef CPU) {
   if (CPU == "generic")
     return ARMV8A;