• Technus@lemmy.zip
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    5 months ago

    We don’t even have true 64-bit addressing yet. x86-64 uses only 48 bits of a 64 bit address and 64-bit ARM can use anything between 40 and 52 depending on the specific configuration.

        • AlphaAutist@lemmy.world
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          5 months ago

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

          • Technus@lemmy.zip
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            4 months 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.

        • just_another_person@lemmy.world
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          5 months ago

          I bet you just recycle thoughts and comments because you have none of your own, but want to feel that “upside” of your sad interaction with people on the Internet.