[clang] [llvm] [LoongArch] add la v1.1 features for sys::getHostCPUFeatures (PR #115832)

[via cfe-commits]

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@@ -135,8 +135,13 @@ void loongarch::getLoongArchTargetFeatures(const Driver &D,
     Features.push_back("+lsx");
 
   std::string ArchName;
-  if (const Arg *A = Args.getLastArg(options::OPT_march_EQ))
+  if (const Arg *A = Args.getLastArg(options::OPT_march_EQ)) {
     ArchName = A->getValue();
+    if (ArchName == "native")
+      for (auto &F : llvm::sys::getHostCPUFeatures())
+        Features.push_back(
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tangaac wrote:

ArchName `"native"` will be lost after `postProcessTargetCPUString(ArchName, Triple);`

It needs to make a copy of `"native"` or use the original `A->getValue()`  after `getHostCPUFeatures`

https://github.com/llvm/llvm-project/pull/115832