From: muta...@gmail.com   
      
   On Monday, July 12, 2021 at 6:53:07 PM UTC+10, wolfgang kern wrote:   
      
   > >> shifts. Or surely I can at least match the 80286 and do   
   > >> (effective) 8-bit shifts. That would be a load of fun.   
   > >> I guess it depends how many selectors I can define on   
   > >> the 80386. I'll run everything in supervisor mode, so I   
   > >> can use both GDT and LDT if that helps.   
      
   > so why don't you stick to 386 and forget no more existing   
   > old crap ?   
      
   I would like to have a solution to the 80286 too.   
      
   > > And if I can get the 8086 to trap and ignore db'66' and   
   > > db'67' I will be able to have 16-bit executables that work   
   > > on either shift value.   
      
   > Now that's a really bad idea. compiled code may look like:   
   >   
   > 66 b8 44 33 22 11 MOV eax,imm32   
      
   No, I won't use 32-bit instructions.   
      
   > 67 03 84 11 55 44 33 22 ADD ax,[ecx+edx+d32]   
   >   
   > so guess what's left w/o these prefixes:   
   >   
   > b8 44 33 MOV ax,imm16   
   > 22 11 AND dl,[bx+di]   
      
   If I just have bb 44 33, will it work on both the 8086   
   and the 80386?   
      
   > But IIRC 66 and 67 were ignored anyway on real 86/88.   
      
   Well that's fantastic then.   
      
   Unless I'm missing something. Something that the   
   compiler can't work around.   
      
   BFN. Paul.   
      
   --- SoupGate-Win32 v1.05   
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