[llvm] [ARM][TableGen][MC] Change the ARM mnemonic operands to be optional for ASM parsing (PR #83436)

[Ivan Kosarev via llvm-commits]

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@@ -608,12 +627,19 @@ struct MatchableInfo {
   void buildInstructionResultOperands();
   void buildAliasResultOperands(bool AliasConstraintsAreChecked);
 
-  /// operator< - Compare two matchables.
-  bool operator<(const MatchableInfo &RHS) const {
+  /// comp - Compare two matchables.
+  bool comp(const MatchableInfo &RHS, const CodeGenTarget &Target) const {
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kosarev wrote:

We could probably use the chance and give it some meaningful name. Something like `shouldBeMatchedBefore()` maybe?

https://github.com/llvm/llvm-project/pull/83436