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   Ryan Castellucci :nonbinary_flag: (ryanc@infosec.exchange)'s status on Saturday, 07-Jun-2025 02:20:37 JST Ryan Castellucci :nonbinary_flag:

   So anyway, some people do crossword puzzles, I do assembly golf to cryptographic algorithms. This generates the 288 bytes of magic numbers for SHA2-256 in 164 bytes while still following the SysV AMD64 ABI.

   https://gist.github.com/ryancdotorg/0d1baee4f3caf055c5931ce088e1c283#file-sha2_const-s

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     John Ripley (jripley@mastodon.social)'s status on Saturday, 07-Jun-2025 04:21:03 JST John Ripley

     in reply to

     @ryanc Wonder how small that could get without all the calling convention overhead, which looks like about half the binary.

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     Ryan Castellucci :nonbinary_flag: (ryanc@infosec.exchange)'s status on Saturday, 07-Jun-2025 04:21:03 JST Ryan Castellucci :nonbinary_flag:

     in reply to

     • John Ripley

     @jripley saving/restoring rbp and rbx actually saved bytes due to shorter opcode encodings. Those account for eight bytes, and then two bytes to clear the FPU stack, so ten bytes total.