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   comp.lang.asm.x86      Ahh, the lost art of x86 assembly      4,675 messages   

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   Message 4,412 of 4,675   
   R.Wieser to All   
   Re: FPU (x87) code debugging.   
   09 Aug 21 15:50:18   
   
   From: address@nospicedham.not.available   
      
   Robert   
      
   >>> Well, please make sure the pointer is correct   
   >>   
   >> :-) And how do you propose that should be done ?   
   >> It sounds like a great idea, but ...   
   ...   
   > use MOV.   
      
   How would that change anything ?    If the target for an FXSAVE is wrong   
   enough that it causes an exception, how /wouldn't/ that be in the same way   
   wrong for a MOV ?  (lets forget about alignment for a moment)   
      
   It would even be making the problem larger, as you would than need to pick a   
   REG value too - and wonder if it perhaps is having a negative influence on   
   the result.   
      
   FWI, I tried several R/M values, none of which wanted to work.   Bad luck I   
   guess.   
      
   In retrospect I should perhaps have tried loading all the common registers   
   with the same value and tried all R/M values until something worked.  On   
   success it would be a case of determining which register is the source, and   
   than look back at the instruction set to find a match - and from it figure   
   out what the/my mistake was.   
      
   > Zero origin, power-of-two size.  Check on both.   
   > Ever wonder why there are so many buffers this way?   
      
   No, never.  Really ...    
      
   > Debugging with MOV test (hand-assembled) could have caught.   
      
   I doubt it.  See above.   
      
   Regards,   
   Rudy Wieser   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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