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163 points wmf | 1 comments | | HN request time: 0.2s | source
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drewg123 ◴[] No.45367075[source]
Does anybody know if the X2 supports the x86 Total store ordering (TSO) memory ordering model? That's how Apple silicon does such efficient emulation of x86. I'd think that would be even MORE important for a Windows ARM64 laptop where there is so much more legacy x86 software going back decades.
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bri3d ◴[] No.45367322[source]
Does anyone have benchmarks for Rosetta with TSO vs the Linux version with no-TSO? I guess it might be a bit challenging to achieve apples to apples, although you could run a test benchmark on OSX and then Asahi on the same hardware, I think?

I've always been curious about just how much Rosetta magic is the implementation and how much is TSO; Prism in Windows 24H2 is also no slouch. If the recompiler is decent at tracing data dependencies it might not have to fence that much on a lot of workloads even without hardware TSO.

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ack_complete ◴[] No.45368478[source]
People who have worked on the Windows x64 emulator claim that TSO isn't as much of a deal as claimed, other factors like enhanced hardware flag conversion support and function call optimizations play a significant role too:

http://www.emulators.com/docs/abc_exit_xta.htm

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1. bri3d ◴[] No.45369177[source]
This is more like what I’d expect! This is a great article too, thank you, this is the kind of thing I come to HN for :)