From: terje.mathisen@tmsw.no   
      
   MitchAlsup wrote:   
   > CARRY in My 66000 essentially provides an accumulator for a few instructions   
   > that supply more operands to and receives another result from a calculation.   
   > Most multiprecision calculation sequences are perfectly happy with another   
   > register used as an accumulator.   
      
   I think I've said so before, but it bears repeating:   
      
   I _really_ love CARRY!   
      
   It provides a lot of "missing link" operations, while adding zero extra   
   bits to all the instructions that don't need it.   
      
   That said, if I had infinite resources (in this case infinity == 4   
   sources), I would like to have an unsigned integer MulAddAdd like this:   
      
     (hi, lo) = a*b+c+d   
      
   simply because this is the largest possible building block that cannot   
   overflow, the result range covers the full 128 bit space.   
      
    From what you've taught us about multipliers, adding one (or in this   
   case two) extra inputs to the adder that aggregates all the partial   
   multiplication products will be close to free in time, but the routing   
   of the extra set of inputs might require an extra cycle?   
      
   Terje   
   --   
   -    
   "almost all programming can be viewed as an exercise in caching"   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)