[clang] [llvm] [AArch64] Add ability to list extensions enabled for a target (PR #95805)

[Tomas Matheson via cfe-commits]

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@@ -116,7 +116,9 @@ const AArch64::ArchInfo *AArch64::parseArch(StringRef Arch) {
 std::optional<AArch64::ExtensionInfo>
 AArch64::parseArchExtension(StringRef ArchExt) {
   for (const auto &A : Extensions) {
-    if (ArchExt == A.Name || ArchExt == A.Alias)
+    if (A.UserVisibleName.empty() && !A.Alias)
+      continue;
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tmatheson-arm wrote:

This seems redundant when looking at the following `if` condition, maybe we actually want to check if `ArchExt.empty()` instead?

https://github.com/llvm/llvm-project/pull/95805