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by the8472 2249 days ago
> I'm not sure that's true: rep movs is pretty fast these days.

That's only true if you target skylake and newer. If you target generic x86_64 then compilers will only emit rep mov for long copies due to some CPUs having a high baseline cost for it. There's some linker magic that might get you some optimized version when you callq memcpy, but that doesn't help with inlined copies.
1 comments
geocar 2248 days ago
I think people with computers more than five years old already know that their computer is slow.

Why exactly do you think seven-years-old is too-old, but five-years-old isn't?

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the8472 2248 days ago
That is irrelevant. The default target of compilers is some conservative minimum profile. Any binary you download is compiled for wide compatibility, not to run on your computer only.
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