Improve performance

[Uzlopak]

Currently working on the performance of this package.

There are still some perf gains to get.

Checklist

• run npm run test and npm run benchmark
• tests and/or benchmarks are included
• documentation is changed or added
• commit message and code follows the Developer's Certification of Origin
  and the Code of conduct

[mcollina]

Note that we are not using this module in Fastify right now, but we switched back to upstream.

I'm ok to switch again if this gives an improvement.

[Uzlopak]

The thing is that we have already improvements because our forwarded fork is significantly faster.
fastify/forwarded#41

So we should have switched long time ago. :D

I am currently working on improving the performance for checking if the ip is trustable.

[mcollina]

Can you make the switch again?

[mcollina]

lgtm

[kibertoad]

is symbol-by-symbol check faster than resolving slice and comparing it as a whole?

[Uzlopak]

from my experience: yes.

[Uzlopak]

sry, I have to investigate something.