[PATCH] D17293: [MC] AsmLexer: 30% speedup on tests, added extensible identifier's character set support.

[Rafael Espíndola via llvm-commits]

>> Just isAllowedChar?
> Nice, may be isAllowedIDChar?

Yes, that is fine.

>> > Well it based on my previuos experience on Windows where we had lexer
>> using these routines eating up to 10% of scan time. Probably not so
>> "generally" as I stated though. I'm not insisting on this particular change and
>> can remove it.
>>
>> Yes, please leave it out. It can be done as an independent patch.
>>
>> BTW, how exactly have you benchmarked this?
>
> Ran all MC\*.* tests several times and measured time. To be honest I didn’t benchmarked individual contribution of  isDigit change. It mostly benefits from single "in bitvector" check.

That can be somewhat noisy because it consists of many small files. I
will try to produce a single big .s and upload it somewhere.

Cheers,
Rafael