[clang] [RISCV] Cache required extensions string for RVVIntrinsicDef (PR #143503)

[Brandon Wu via cfe-commits]

https://github.com/4vtomat updated https://github.com/llvm/llvm-project/pull/143503

>From 06013a60b51bdc61977c19c80231ed93c0278d66 Mon Sep 17 00:00:00 2001
From: Brandon Wu <songwu0813 at gmail.com>
Date: Tue, 10 Jun 2025 03:07:12 -0700
Subject: [PATCH] [RISCV] Use StringRef for RequiredExtensions in
 RVVIntrinsicDef

This prevents many duplicated copies of required extensions string.
---
 clang/lib/Sema/SemaRISCV.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/clang/lib/Sema/SemaRISCV.cpp b/clang/lib/Sema/SemaRISCV.cpp
index 9f70be746eb3f..9eab0c2a0df6a 100644
--- a/clang/lib/Sema/SemaRISCV.cpp
+++ b/clang/lib/Sema/SemaRISCV.cpp
@@ -47,7 +47,7 @@ struct RVVIntrinsicDef {
   std::string BuiltinName;
 
   /// Mapping to RequiredFeatures in riscv_vector.td
-  std::string RequiredExtensions;
+  StringRef RequiredExtensions;
 
   /// Function signature, first element is return type.
   RVVTypes Signature;