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   Pleroma-tan (kirby@lab.nyanide.com)'s status on Saturday, 11-May-2024 01:37:03 JST Pleroma-tan

   • Haelwenn /элвэн/ :triskell:
   • Pleroma-tan
   @lanodan or maybe it's not a lot?
   • Embed this notice
     Haelwenn /элвэн/ :triskell: (lanodan@queer.hacktivis.me)'s status on Saturday, 11-May-2024 01:44:19 JST Haelwenn /элвэн/ :triskell:

     in reply to
     @kirby Seems a lot to me but while I know bits of assembly I'm unfamiliar with how they are encoded.
   • Embed this notice
     :ihavenomouth: (inginsub@clubcyberia.co)'s status on Saturday, 11-May-2024 01:45:30 JST :ihavenomouth:

     in reply to

     • Haelwenn /элвэн/ :triskell:
     @kirby @lanodan some of the newer instructions are ridiculously long, and I’m sure intel won’t stop until they use up all 15 bytes
     Pleroma-tan likes this.
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     Pleroma-tan (kirby@lab.nyanide.com)'s status on Saturday, 11-May-2024 01:49:21 JST Pleroma-tan

     in reply to

     • :ihavenomouth:
     • Haelwenn /элвэн/ :triskell:
     @Inginsub @lanodan i mean with instruction names like cvttsd2si....
   • Embed this notice
     LEdoian (ledoian@pleroma.ledoian.cz)'s status on Saturday, 11-May-2024 05:31:25 JST LEdoian

     in reply to

     • Haelwenn /элвэн/ :triskell:

     @lanodan @kirby Intuitively, I thought that this would be mostly needed for nontrivial immediate values in the instructions. But now I am not sure: prefixes, instruction "name", up to four arguments (incl. weird addressing modes of x86_64), it might add up.

     A quick disassembly of /bin/df shows that 9-byte instructions are rather common:

     b974: 64 48 2b 04 25 28 00 sub %fs:0x28,%rax b97b: 00 00

     I think this is some security guard or sth; the last 4 bytes look like an imm32 value. I am not sure whether "full" 15-byte instruction exists, though…

     (Looked at some AVX instructions, they take ~7 bytes. Maybe some horror like VEXTRACTF128 might be long, it has 3 arguments, idk)

     Haelwenn /элвэн/ :triskell: likes this.
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     2c-1-nbome-accel (enzymical@ryona.agency)'s status on Thursday, 23-May-2024 13:25:46 JST 2c-1-nbome-accel

     in reply to

     • :ihavenomouth:
     • Haelwenn /элвэн/ :triskell:
     @kirby @Inginsub @lanodan thankfully it's not like the cpu reads in the instruction names like GF2P8AFFINEINVQB
     Pleroma-tan likes this.