Post AlqQAD3Q4V0qxgSJHs by wollman@mastodon.social
(DIR) More posts by wollman@mastodon.social
(DIR) Post #AlqCsb5yeJiuuKvJoW by foone@digipres.club
2024-09-09T22:38:46Z
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I'm gonna run a tournament for all the x86 instructions and let people vote in polls. personally I'm betting on PSADBW, from SSE2. It's a powerful tool for quickly comparing image hashes, which was very almost useful back when I did my senior project in 2008
(DIR) Post #AlqD29lx5f3V3x7CQi by munin@infosec.exchange
2024-09-09T22:41:41Z
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@foone idk, I like to MOV it. Got a catchy rhythm that way.
(DIR) Post #AlqDMD9KFDJxKObuvw by foone@digipres.club
2024-09-09T22:44:55Z
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@munin well it is turing complete, so it's really all you need!
(DIR) Post #AlqDSaCrQpqoZkIome by cvtsi2sd@hachyderm.io
2024-09-09T22:44:51Z
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@foone my 80186 cats are ready for this competition https://photos.app.goo.gl/RQ8UL3NtJJkex6kYA(no actually they aren't, they'd rather just sleep into the sun)
(DIR) Post #AlqE1eOjq76Xi8a07k by clairely_player_one@mastodon.gamedev.place
2024-09-09T22:45:46Z
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@foone REPE CMPSB “one” instruction to compare runs of 8-bit values
(DIR) Post #AlqF0fvUlu6E7E04tU by foone@digipres.club
2024-09-09T22:46:09Z
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@clairely_player_one oh yeah the REP prefix ones are awesome
(DIR) Post #AlqFG1E9rD5yWV2uW0 by harborsec@infosec.exchange
2024-09-09T22:47:36Z
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@foone +1 for ADDSUBPS, or "Adds odd-numbered single precision floating-point values of the first source operand (second operand) with the corresponding single precision floating-point values from the second source operand (third operand); stores the result in the odd-numbered values of the destination operand (first operand). Subtracts the even-numbered single precision floating-point values from the second source operand from the corresponding single precision floating values in the first source operand; stores the result into the even-numbered values of the destination operand."(https://www.felixcloutier.com/x86/addsubps)
(DIR) Post #AlqFbt0v4kDXQ7HU8m by cvtsi2sd@hachyderm.io
2024-09-09T22:50:04Z
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@foone I may be biased, but cvttsd2si would (begrudgingly) be my choice. It's the wrong operation (generally one would actually want cvtsd2si, i.e. conversion with rounding), but before it all double -> int casts in C required a tortuous instructions sequence fucking up and then restoring the FP control word.
(DIR) Post #AlqFkSbocMF28Jcws4 by foone@digipres.club
2024-09-09T22:51:43Z
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@pthariensflame very handy. I'm always doing Galois Field Affine Transformations
(DIR) Post #AlqGGUqLqTuoKVhbFo by vfig@mastodon.gamedev.place
2024-09-09T23:04:22Z
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@foone my favourite is always going to be NOP, its just so useful!
(DIR) Post #AlqGGWWDcJ01WeIY9Q by vfig@mastodon.gamedev.place
2024-09-09T23:06:37Z
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@foone my second favourite is REP STOSB, which to me has always sounded like a name from the hitchhiker's guide to the galaxy. i can absolutely imagine Ford Prefect swanning around Frogilthus IV with his old pal Rep Stosb.
(DIR) Post #AlqGfcCVczmWO72mSO by foone@digipres.club
2024-09-09T23:13:15Z
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@zoe that does sound very, very cursed
(DIR) Post #AlqI06llmedUwOs9Q0 by SvenGeier@mathstodon.xyz
2024-09-09T23:37:14Z
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@foone NOP !
(DIR) Post #AlqQAD3Q4V0qxgSJHs by wollman@mastodon.social
2024-09-10T01:08:19Z
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@foone My favorite for the past 40 years has been ADD [BX+SI],AL which I used to see a lot in DEBUG.
(DIR) Post #AlqilGwsLxswvhDXO4 by bmartin427@techhub.social
2024-09-10T04:36:38Z
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@foone ah the sad tale of RDTSC. Such a brief window of usefulness before variable clocking and multi core broke it.
(DIR) Post #AlqoaerFiadlceuQM4 by krans@mastodon.me.uk
2024-09-10T05:42:26Z
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@foone I'm a big fan of CMPXCH16B. It was very useful for my PhD research.
(DIR) Post #AlrkQCafkuWaOksA2i by dascandy@infosec.exchange
2024-09-10T16:30:07Z
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@foone Going for LAHF, for the most obsolete but still useful instruction, SLDT for "nobody ever used this and nobody ever will", and AAA for the feeling of doing arithmetic in ASCII characters.