[llvm] [MCParser][NFCI] Deduplicate isIdentifierChar. (#218100) (PR #218851)

[via llvm-commits]

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@@ -130,6 +131,17 @@ class AsmLexer {
     return Tok;
   }
 
+  /// LexIdentifier: [a-zA-Z_$.@?][a-zA-Z0-9_$.@#?]*
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zhangweize9-cyber wrote:

That’s a good point! However, after giving it some further thought, I realized my proposal still has some shortcomings. So, I plan to move forward with MaskRay’s proposal (i.e., #219084) and close my own for now; we can discuss it later depending on how things go.

https://github.com/llvm/llvm-project/pull/218851