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Why we don't have 128-bit CPUs (www.xda-developers.com)
submitted 2 years ago by to c/technology@lemmy.world
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[–] 34 points 2 years ago (1 child)

I actually didn’t know that about addressing before your comment and so I found it very interesting, thanks

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  • [–] 2 points 2 years ago

    Some applications use those unused bits to add tags to pointers but it's important to mask those out before attempting to dereference the address. I'm not sure about ARM but x86-64 requires bits 49-63 to be copies of bit 48 (kinda like sign-extension), ironically to ensure that no one is using those bits to store extra data.

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