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   binkle (binkle@clubcyberia.co)'s status on Sunday, 02-Aug-2026 04:02:44 JST binkle

   does anyone happen to know the overhead involved in parameter passing via C calling convention?

   By the disassembly of this test file I can see there are some additional instructions compared to the implicit-use-of-global-data version but I'm not familiar enough with x86 to be able to make a determination on whether these are "free" or not and in what cases they might or might not be

   yes I know this "probably doesn't matter" and is "microoptimizing and rabbitholing" but I want to know the answer anyway

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     Tyler (tyler@nicecrew.digital)'s status on Sunday, 02-Aug-2026 04:02:43 JST Tyler

     in reply to

     • T man :sex: :puffgiga: :puffpowerroll:
     Cc @theorytoe might know but i don't personally off the top of my head if you're like asking about calling c from whatever lang
     
     Afaik since your parameters are typed if you pass the literal data you might be moving a lot more data in and out of memory instead of just passing a pointer to the memory you intend the function to do something with, like normal convention
     T man :sex: :puffgiga: :puffpowerroll: likes this.
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     T man :sex: :puffgiga: :puffpowerroll: (theorytoe@ak.kyaruc.moe)'s status on Sunday, 02-Aug-2026 04:11:57 JST T man :sex: :puffgiga: :puffpowerroll:

     in reply to

     • Tyler
     @tyler @binkle
     i think op is talking about how c translates to an x86 call
     
     havent really had the situation where I would care about that overhead (and partially because I dont really know much about it) but intuition leads me to believe that there is some miniscule overhead if you have to allocate a stack frame to push operands to. But I would assume that its essentially free if its in cache