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Sharlinyesterday at 9:22 PM2 repliesview on HN

There's also the fact that for all intents and purposes, the real floating-point unit of any x86 in the last 20 years is the SIMD unit, and legacy x87 instructions are emulated on top of that.


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cogman10today at 1:07 AM

I don't believe so.

The issue is that x87 is 80bit floats which is awkward. As such, it still requires dedicated hardware.

Intel has proposed and abandoned pushing a new x86 architecture [1] which tweaks x86 instructions to fit better with the reality that everything is 64bit now. Part of that proposal was to make x87 work with 64bit floats instead of 80bit floats (which would have allowed it to share the same floating point units as the SIMD instructions).

[1] https://www.intel.com/content/www/us/en/developer/articles/t...

whaleofatw2022today at 12:34 AM

One exception that does come to mind, is .Net Framework on x86. AFAIR that didn't use SSE or SSE2. (In x64 mode it did however, since those were part of the baseline for x64)

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