rs6000 machine description/assembly question

Spundun spundun@ISI.EDU
Tue Nov 26 01:07:00 GMT 2002


On Mon, 2002-11-25 at 17:16, Paul Koning wrote:
> > now if you "and" this with the number above, you get
> > [some zeros]1[n zeros]. so cntlzw on this will be n (same as that on the
> > original x)
> > Can you comment on this reasoning please? I am sure there something
> > silly on my part.
> 
> I don't speak RS6000, but I assume "cntlzw" means something like
> "count leading zeroes"?  In your example, "n" is the count of
> *trailing* zeroes, not leading zeroes.  If cntlzt means what I
> guessed, then when you apply it to (x & (-z)) it returns the count off
> "some zeroes" above -- from which you can get "n" by subtracting that
Ohhh, sorry, got confuse in the endian-ness while reading the doc :(
Thanx everyone.
Spundun
> from the size in bits minus one.
> 
>      paul




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