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   alt.os.development      Operating system development chatter      4,255 messages   

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   Message 3,359 of 4,255   
   Joe Monk to All   
   Re: segmentation   
   23 Oct 22 15:14:02   
   
   From: joemonk64@gmail.com   
      
   > And on the theoretical NEC hardware I described above, it   
   > will instead be:   
   >   
   > 2B0:013 and 1E0:003 that point to the same physical address in memory.   
   >   
      
   Impossible.   
      
   1E0, shifted 5 left , is 3C0.   
      
   2B0, shifted 5 left, is 560.   
      
   > And the existing code base doesn't care one iota because it doesn't   
   > hardcode EITHER of those addresses, nor does it even attempt to   
   > compare such disparate addresses (it would fail if it did, because   
   > C code doesn't normally normalize pointers before comparison).   
   >   
      
   The existing code base is written that DS, CS, ES, etc are 4 bit shifts,   
   performed by hardware.   
      
   > BFN. Paul.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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