[llvm] [AArch64][llvm] Generate asm parser extension map from TableGen (NFC) (PR #191045)

[via llvm-commits]

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@@ -53,6 +54,66 @@ static void checkFeatureTree(const Record *Root) {
   }
 }
 
+static bool allowInAArch64AsmParserDirective(const Record *Rec) {
+  // The generated asm parser extension table is used for both directive lookup
+  // and required-feature diagnostics. Some extensions still need to appear in
+  // diagnostics, but must not be accepted by .arch/.arch_extension/.cpu.
+  return StringSwitch<bool>(Rec->getName())
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CarolineConcatto wrote:

I was thinking about using FeatureLookupBuilder  that Ben used for clang, but looking at your patch now it does not have a switch statement as it had before

https://github.com/llvm/llvm-project/pull/191045