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  Anyone have a favourite use of SDP that isn't approximating max-cut? (it's cool but also almost always *the* example, so I've seen it)

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  grevmul by a constant x is a bitwise-linear function that can be represented by a block-matrix with a neat recursive definition

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  Some relationships between expressions. Arrow from X to Y means that X is unsigned ≥ Y. addus is addition with unsigned saturation, subus is subtraction with unsigned saturation, avg_down is the average rounded down.

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  AVX-512 full-register variable grev, with a single control mask. Because why not. There are obvious variants such as grevving each qword independently.

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  Software was supposed to be the easy part to replace, but it fossillized more than hardware

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  I found out one of my ancestors has a Stolperstein: Duifje Aptroot-Wijnberg died in 1944 in Enschede, at age 88, after living there for a while (originally the family lived in Leek). She died during the war, but I don't know any details. Two of her daughters, Lea and Hester, were murdered by the nazis. Her youngest son Siemon Aptroot was my great-grandfather.

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  cool

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  "Haha you're so silly, comments don't make the compiler compile the code the way you tell it to" vs /*synthesis syn_ramstyle="block_ram"*/

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  Recent releases of Yosys oss-cad-suite-build don't work for me, I get some error about msgpack package missing and I cannot install it (yes I tried, if that worked in any normal way I wouldn't be here talking about it, the copy of pip that comes with it has no SSL and refuses to do anything) December 2025 version still works posted on mastodon instead of a github issue because I'd have to log in with 2FA

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  Of course, plugging a pico probe and a tang nano into neighboring USB ports doesn't work (in very odd ways - devices listed but no longer have any device info and cannot be used) but plugging them into ports sufficiently far apart does the trick. After all why would USB ever just work.

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  Any tips on achieving time travel? I'm not asking for much, maybe around 30 nanoseconds no big deal

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  Does anyone here know the SereneDB people, I wanted to talk to them about bit-matrix transposes but not over github or linkedin or something stupid like that.

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  Ever wanted to invert a permutation using only pshufb? Yeah. The worst thing is it's not even *that* bad