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

[Sergei Barannikov via llvm-commits]

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@@ -7290,64 +7304,68 @@ bool ARMAsmParser::ParseInstruction(ParseInstructionInfo &Info, StringRef Name,
     // on the Mnemonic based checking to correctly figure out when to put
     // a k_CondCode operand in the list. If we're trying to match the label
     // version, remove the k_CondCode operand here.
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s-barannikov wrote:

De-indent the comment, too.

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