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   Phantasm (phnt@fluffytail.org)'s status on Tuesday, 08-Apr-2025 21:01:06 JST Phantasm

   in reply to

   • Kate
   • akkoma flavored lizzy (fleckenstein@lizzy.rs alt)
   @k4t3 @lizzy MSVC is littered with these weird quirks everywhere. The easiest explanation is that their optimizer simply does not exist. It's the reason why code compiled with MSVC is usually slower than whatever mingw or clang creates.
   • Embed this notice
     Kate (k4t3@comp.lain.la)'s status on Tuesday, 08-Apr-2025 21:01:09 JST Kate

     in reply to

     • akkoma flavored lizzy (fleckenstein@lizzy.rs alt)
     @lizzy My theory is that their optimizer either doesn't save the precondition rax = 0 for the branch, or it doesn't correctly map eax to the lower 32bits of rax.
     From my quick testing, it seems like theory B is more likely, but then again, I don't know _that_ much about their internals.
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     akkoma flavored lizzy (fleckenstein@lizzy.rs alt) (lizzy@social.vlhl.dev)'s status on Tuesday, 08-Apr-2025 21:01:10 JST akkoma flavored lizzy (fleckenstein@lizzy.rs alt)

     in reply to

     • Kate

     @k4t3 i see this a LOT while reverse engineering programs. if (x == 0) { x = 0; ... } and so on. just why

   • Embed this notice
     Kate (k4t3@comp.lain.la)'s status on Tuesday, 08-Apr-2025 21:01:14 JST Kate
     MSVC back at it again with only the finest codegen..
     Doughnut Lollipop 【記録係】:blobfoxgooglymlem: likes this.