Re: Numerical code efficiency

On Sun, 12 Oct 2003 11:17:21 -0400, "Dan Muller"
<[email protected]> said:
> 2. Looking at the disassembled functions, i noticed that svref results
>    in an actual function call, as does the call to #'+. Is there any
>    way around this? Declaiming these inline doesn't work; I get a
>    warning that the source isn't accessible.

It looks like there is no inlining of #'+ for floats. The following
inlines correctly for fixnums for example:

(defun test (a b)
    (declare (optimize (speed 3) (safety 0))
             (type fixnum a)
             (type fixnum b))
    (the fixnum (+ a b)))

But the following doesn't for floats:

(defun test (a b)
    (declare (optimize (speed 3) (safety 0))
             (type double-float a)
             (type double-float b))
    (the double-float (+ a b)))

As for whether it's typical for Lisp compilers, I don't know. CMUCL
(which is well known for its optmisation abilities) will inline the
second example.

Chris.
-- 
  Chris Double
  [email protected]

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