[clang] [Clang][TableGen] Use StringRef in FlattenedSpelling (PR #113809)

[Aaron Ballman via cfe-commits]

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@@ -49,40 +49,38 @@ using namespace llvm;
 namespace {
 
 class FlattenedSpelling {
-  std::string V, N, NS;
+  StringRef V, N, NS;
   bool K = false;
   const Record &OriginalSpelling;
 
 public:
-  FlattenedSpelling(const std::string &Variety, const std::string &Name,
-                    const std::string &Namespace, bool KnownToGCC,
-                    const Record &OriginalSpelling)
+  FlattenedSpelling(StringRef Variety, StringRef Name, StringRef Namespace,
+                    bool KnownToGCC, const Record &OriginalSpelling)
       : V(Variety), N(Name), NS(Namespace), K(KnownToGCC),
         OriginalSpelling(OriginalSpelling) {}
   explicit FlattenedSpelling(const Record &Spelling)
-      : V(std::string(Spelling.getValueAsString("Variety"))),
-        N(std::string(Spelling.getValueAsString("Name"))),
-        OriginalSpelling(Spelling) {
+      : V(Spelling.getValueAsString("Variety")),
+        N(Spelling.getValueAsString("Name")), OriginalSpelling(Spelling) {
     assert(V != "GCC" && V != "Clang" &&
            "Given a GCC spelling, which means this hasn't been flattened!");
     if (V == "CXX11" || V == "C23" || V == "Pragma")
-      NS = std::string(Spelling.getValueAsString("Namespace"));
+      NS = Spelling.getValueAsString("Namespace");
   }
 
-  const std::string &variety() const { return V; }
-  const std::string &name() const { return N; }
-  const std::string &nameSpace() const { return NS; }
+  StringRef variety() const { return V; }
+  StringRef name() const { return N; }
+  StringRef nameSpace() const { return NS; }
   bool knownToGCC() const { return K; }
   const Record &getSpellingRecord() const { return OriginalSpelling; }
 };
 
 struct FlattenedSpellingInfo {
-  FlattenedSpellingInfo(std::string Syntax, std::string Scope,
-                        std::string TargetTest, uint32_t ArgMask)
+  FlattenedSpellingInfo(StringRef Syntax, StringRef Scope,
+                        const std::string &TargetTest, uint32_t ArgMask)
       : Syntax(Syntax), Scope(Scope), TargetTest(TargetTest), ArgMask(ArgMask) {
   }
-  std::string Syntax;
-  std::string Scope;
+  StringRef Syntax;
+  StringRef Scope;
----------------
AaronBallman wrote:

Same concern here as above.

https://github.com/llvm/llvm-project/pull/113809