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Wow, okay. I would imagine this makes mathematicians quite angry? I guess you're responsible for all the operations you use in your proof being well-behaved. It sounds like subtrac…

Word.

re2c works like a charm. I'm generally confident that I couldn't write faster scanners by hand if I tried.

This code was written a while ago, but I decided it merited a write-up recently.

I have DietPi running on a Raspberry pi Zero W (armv6l), which is a system that's supported by barely any distros nowadays. It was easy to preseed, has the absolute bare minimum am…

This is pretty much `assembly language the game`: https://tomorrowcorporation.com/humanresourcemachine It's not a useful architecture, but it teaches the thought process really wel…

The array lookup approach taken in part two: https://owen.cafe/posts/the-same-speed-as-c/ But taking the length of the string as a parameter is not, because that changes the proble…

Kind words, much appreciated!

I guess the question is whether the compiler should optimize a function containing a loop for a single null terminator, or for more data. I would suggest the latter is what you wan…

So I actually did try that, but and IIRC it didn't produce a CMOV with either gcc or clang. I didn't put it in the repo because it wasn't an improvement (on my machine) and I decid…

That's the thing, a C compiler has all the information it needs to know that the maximum amount of times a '\0' can be processed in the loop is once (because the function returns),…

Very interesting approach. I should probably have specified that the somewhat naive assembly in `02-the-same-speed-as-c/loop-5.x64.s` is the fastest version I have. On my machine I…

Nice! There's a part two in which I rewrote the C. I got a 12x speedup :) https://owen.cafe/posts/the-same-speed-as-c/ And as others have pointed out, you can tweak the input, then…

The version that's friendly to the compiler is described in part two: https://owen.cafe/posts/the-same-speed-as-c/ It achieves 3.88GiB/s I intentionally didn't go down the route of…

> because without FDO (or PGO) the compiler has no idea how likely each branch is to be taken So, the maximum amount of times you can hit '\0' is once in the string, because then t…

Yes, I explained in the `Benchmarking setup` section that I used `march=native`, but I guess I forgot to mention I used -O3.

I'd probably look for a tech co-founder. Such a small percentage of startups make it, and having a learning-as-you-go tech team will not help those already small chances. That said…

A clickbait title for an in-depth look at hand-optimizing a very simple loop.

I would. A few basic requirements are: git, linux, a desktop computer (or to be allowed to use my own)

I'm using lemon to parse a programming language. Lemon produces this report for my grammar: Parser statistics: terminal symbols................... 19 non-terminal symbols..........…

I migrated my main personal project (a programming language written in C) to Tup recently. So far I love it, it seems to 'just work'. Some highlights: No need to map header (or oth…