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DOS demos run in browsers through traced, cycle-accurate WebAssembly recompilation

treylorswift.github.io Editor score 8/10

The demos are traced in an x86 emulator, translated instruction-for-instruction to C, compiled to WebAssembly, and checked against the emulator event by event. The technique offers a concrete approach to preserving timing and behavior when porting legacy software.

What

An x86 emulator traces DOS demo execution, then recompiles the executed code instruction-for-instruction into browser-running WebAssembly.

How

Recorded instructions become C with emulated cycle timing; WebAssembly includes models of the timer, VGA card, and Sound Blaster.

Why it matters

Event-by-event comparison with the emulator helps preserve legacy software behavior while moving execution into browsers.

Read on treylorswift.github.io → Hacker News · 140 comments

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