Re: [Gcl-devel] Boyer benchmark results

[Christophe Rhodes]

Camm Maguire <address@hidden> writes:

>> Using sys-proclaim.lisp and boyer1.cl2, gcl in non-ANSI mode is indeed
>> a bit faster than cmucl (2.45 vs 2.59).
>
> Christophe is right that in this case the conclusion is apples and
> oranges, not so much because of the sys-proclaims, IMHO, but rather
> that the difference is within the effect of the larger ansi image size
> on the result, making it only fair to use the ansi result when
> comparing with cmucl.  I don't know what 'block' mode in cmucl is, but
> I wanted to restate that the sys-proclaim.lisp I sent for convenience
> is output by the compiler, not a human.  It is in effect an optional
> extra optimizing compiler pass, and its effect should therefore be
> comparable to other optimizing instructions given to a compiler, but
> not to code tuning by hand.

Much like CMUCL block compilation, then, which allows the user to
request semantics for the code that are not strictly those ANSI
semantics.  (pass :BLOCK-COMPILE T to COMPILE-FILE; there are even
more aggressive modes which can be found in the CMUCL manual.)

My point is that if you are going to unportably twiddle compiler
switches for maximum speed, then you ought to do so on all
implementations, not simply the one with which you are most familiar.

Cheers,

Christophe
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