Did you try declaring l2-distance-squared inline?  I'm guessing that's
the root of the note message.  Probably accounts for all the consing
too.

-- MMN

On Mon, 2003-10-27 at 13:58, rif wrote:
> 
> I'm trying to optimize the following function (yes, profiling
> indicates that this function is the bottleneck, it's taking the lion's
> share of the time and the consing).
> 
> (defun find-closest-index (point centers)
>   (declare (type simple-array centers)
>            (type (simple-array double-float) point))
>   (let ((best-dist most-positive-double-float)
>         (dist 0.0d0)
>         (index -1))
>     (declare (type fixnum index)
>              (type double-float best-dist)
>            (type double-float dist))
>     (fixtimes (i (array-dimension centers 0))
>        (let ((c (aref centers i)))
>          (declare (type (simple-array double-float) c))
>        (setf dist (the double-float (l2-distance-squared point c)))
>          (when (< dist best-dist)
>            (progn
>              (setf index i)
>              (setf best-dist dist)))))
>     index))
> 
> 
> One of the compiler notes (settings were speed 3, debug and safety 0)
> for this function is:
> 
> ;   (SETF BEST-DIST DIST)
> ; ==>
> ;   (SETQ BEST-DIST DIST)
> ; Note: Doing float to pointer coercion (cost 13) from DIST to BEST-DIST.
> 
> And I cannot for the life of me figure out why I'm getting this.  Any
> ideas?
> 
> Cheers,
> 
> rif
> 
> ps.  Yes, I know that not all of the current type declarations are
> necessary.  I'm still in the "better safe than sorry" stage of
> debugging.  Once I can get that pesky conversion gone, I'll figure out
> which other type declarations are unnecessary.
> 



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