[llvm] [clang] [RISCV] Deduplicate RISCVISAInfo::toFeatures/toFeatureVector. NFC (PR #76942)

[Luke Lau via cfe-commits]

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@@ -42,9 +42,10 @@ static bool getArchFeatures(const Driver &D, StringRef Arch,
     return false;
   }
 
-  (*ISAInfo)->toFeatures(
-      Features, [&Args](const Twine &Str) { return Args.MakeArgString(Str); },
-      /*AddAllExtensions=*/true);
+  const auto ISAInfoFeatures = (*ISAInfo)->toFeatures(/*AddAllExtension=*/true,
+                                                      /*IgnoreUnknown=*/false);
+  Features.insert(Features.end(), ISAInfoFeatures.begin(),
+                  ISAInfoFeatures.end());
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lukel97 wrote:

Argh I was trying to be too clever and forgot that we need to call Args.MakeArgString, I've just replaced it with the push_back loop again.

https://github.com/llvm/llvm-project/pull/76942