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The time the x86 emulator team found code so bad they fixed it during emulation (devblogs.microsoft.com)
79 points by paulmooreparks 1 hour ago
6 comments

I think we're starting to see more of this sort of thing happening now with Proton and Wine gaining prominence in the Linux community. Some games (Elden Ring comes to mind) have bad enough PC ports when they come out that the compatibility layer can incorporate a hotfix to improve performance, while users of the software on the original platform still had to suffer.
Betting Alpha was the native architecture in question. It seemed to have the best support.
> they fixed it during emulation

It means the fix was applied to run during the emulation loop execution, not that the fix was found and applied while the emulation loop was running.

Which would have made it an emulation code escape.

People from Transmeta told me stories about how their translators were full of special case optimizations to fix horrors they discovered in Microsoft Windows itself.
Couldn't they just turn the optimization off for this loop?
They didn't have the code for the offensive program, they were creating the emulator to run it on a different architecture.
> offensive program

Agreed.

Which optimizer replaces a 64k loop with 64k instructions?

Ah, yes. Microsoft's!

> All in all, it took this program 256 kilobytes of code to initialize 64 kilobytes of data.

solidity sweating profusely