[clang] [llvm] [RISCV] Relax march string order constraint (PR #78120)

[Piyou Chen via cfe-commits]

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@@ -695,6 +695,106 @@ RISCVISAInfo::parseNormalizedArchString(StringRef Arch) {
   return std::move(ISAInfo);
 }
 
+static Error splitExtsByUnderscore(StringRef Exts,
+                                   std::vector<std::string> &SplitedExts) {
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BeMg wrote:

Done

https://github.com/llvm/llvm-project/pull/78120