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> Certainly knowledge about it had only started trickling out in the general industry at the time as compilers started exploiting it It was common knowledge am
by guerrilla 5y ago
> Certainly knowledge about it had only started trickling out in the general industry at the time as compilers started exploiting it
It was common knowledge among C programmers long before then, for both security and portability reasons but optimization was also done. Old MacOS even used the higher 8-bits of pointers for MM flags. Other popular systems did equally weird things (think VAX.) That discussion linked to by the Jargon file is from 1992.
- Taniwha 5y agoI've programmed all these, old Macs certainly did weird stuff with the upper bits of pointers, Vaxen though have quite ordinary virtual address spaces, they do use upper bits to choose between page tables but that's about it