Xem

Shameless plug

I made an entire organ synthesizer in under 1024 bytes of html/js (use your keyboard):

https://js1024.fun/demos/2022/23

source / instructions / background:

https://github.com/ThomasBrierley/js1024-mini-b3-organ-synth

The javascript was significantly reduced in size by using regpack, which is a regex based dictionary compression algorithm targetting very small self decompressing javascript. Writing for regpack takes some thinking because you have to try and make the code the most naturally self similar, which often means consciously avoiding more immediate space saving hacks in order to make larger sequences of characters identical - e.g it would usually make sense to not duplicate an expression, unless it's very short and only used a couple times, it usually makes sense to store it in a variable, but the character cost in defining the variable is actually larger than simply duplicating the expression through regpack (even if it's used a lot).

This might be worse than the lzw type compression used in HTTP, I haven't tested, but this was written for a code golfing competition where source size counts not transmitted size... Then again, conceptually this should lend itself to any any dictionary based compression, so zipping the original source (minus the whitespace), may also work out very well.

Here's a web interface that includes terser and regpack: https://xem.github.io/terser-online/

Note that it's usually best to hand minify for regpack, terser is…

386 got trapping privileged accesses wrong, not fixed in 486. Problem is Protected Mode programs (CPL 3) executing CLI and expecting POPF to restore interrupt flag - its ignored AND doesnt trap. Afaik no x86 CPU ever fixed it completely.

Microsoft had some hacks trying to detect and patch known common problem patterns:

Getting MS-DOS games to run on Windows 95: The interrupt flag https://devblogs.microsoft.com/oldnewthing/20160411-00/?p=93281

Virtualbox switches to software tricks: https://docs.oracle.com/en/virtualization/virtualbox/6.0/admin/swvirt-details.html

"In particular, the recompiler is used when guest code disables interrupts and Oracle VM VirtualBox cannot figure out when they will be switched back on. In these situations, Oracle VM VirtualBox actually analyzes the guest code using its own disassembler."

ReactOS didnt even try. "ReactOS' NTVDM on the other hand, is a software emulator just like DOSBox": https://web.archive.org/web/20170723164052/http://community.reactos.org/index.php/news/years-progress-ntvdm-part-1 https://web.archive.org/web/20151216085857/http://community.reactos.org/index.php/news/years-progress-ntvdm-part-2

https://xem.github.io/minix86/manual/intel-x86-and-64-manual-vol3/o_fe12b1e2a880e0ce-996.html

"When the PVI flag is set to 1, the CPL is 3, and the IOPL is less than 3, the STI and CLI instructions set and clear
the VIF flag in the EFLAGS register, leaving IF unaffected. In this mode of operation, an application running…

http://xem.github.io

I'm Maxime, front-end developer and passionate of JavaScript code-golfing.

I make tiny JS demos & games for fun or for contests like JS1K.com and JS13Kgames.com, and write about them (among other front-end experiments) here.

There's also a lot of tech watch and projects involving other topics like retro consoles emulation, Unicode, WebGL, and even a collection of memes and jokes.

Feel free to send feedback, even negative.

(I know the site's style is a bit old now, but I'm updating it!)

Cheers :)

This is not "simple". And I'm not even talking about tracking, why is `all.js` a whooping 1 MB of JavaScript? For example, it clearly includes markdown-it but the website has zero Markdown support as far as I can tell. Spell-checking is the only non-trivial component I can imagine and even that can be plausibly replaced with a native `spellcheck` attribute.

I would instead recommend a beautifully golfed, and yet still quite readable and functional notepad app with <100 bytes of JS: https://xem.github.io/postit/