Re: LW compiler optimizations

On 14 Jan 2025, at 22:21, David McClain <[email protected]> wrote:
> 
> But this indicates that using a displaced array costs me nearly 5x performance degradation, as opposed to your claim of 1% penalty.

I am sorry I am now going to lose my temper.

LEARN TO FUCKING READ.

I will repeat what I actually wrote which you have repeatedly misquoted: 

So let's summarize: the demonstrated performance cost of displaced arrays in an existing CL implementation, after a little macro, is *under one percent*.

No, I know this is hard, but you need to read all of that sentence.  All of it.  In case that really is too hard, here are two important bits:

"after a little macro": this is the macro which is described in that message, and which is included in some of the code I posted.  It turns a displaced array into its underlying simple array and optionally provides a macro to reference that underlying array with a suitable offset.
"in an existing CL implementation".  Being, in this case, as I made clear, SBCL (although LW can be persuaded, as is demonstrated by the tsda/tsoa function in ts-dar.lisp.

I know it's hard to read what people say, but really, it is not that hard.

OK, I feel at this point the LW people will be fully justified from removing me from the list.  That's fine.

--tim