wouter van ooijen wrote:

>>its peculiar instructions, I ended up with a "integer 
>>constant parser" 
>>which was able to generate the lowest possible number of 
>>instructions to 
>>express it (using Shifts etc).
> 
> Why would a compiler want to do that, for speed? For size 1 instruction
> + 1 PC-relative-adressable constant is enough!

Well, now I don't remember the exact reasons, but: (I still have the 
sources!)

more or less, since the 32bit Op-Code could handle only some limited 
Constant Value in its fields, say 10 bits (i.e. max = 1023), but there 
was also a "Shift" field, say up to 8, you could sayt that:
* for numbers below 1023, use MOV D0,#number,Shift=0
* for numbers >= 1024 but with zero bits in the lowest positions and a 
total amount of significative bits still <= 10, use MOV 
D0,#number,Shift=shift
* for other numbers >= 1024 , MOV D0,#(number & 1023),Shift=0 .. ADD 
DO,#(number >> 10),Shift=shift




-- 
Ciao, Dario
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