Re: compiler generated output

Hello,

Skarmander wrote:

> Spiro Trikaliotis wrote:
>> Hallo Skarmander,
>>
>> Skarmander <spamtrap@xxxxxxxxxx> schrieb:
>>
> And that's not my address, it's yours. You or your client seem to have
> issues with attribution, no? :-D

I'm sorry for that confusion. Charles already explained this to you.

>>>Spiro Trikaliotis wrote:
[...]

> Something tells me two separate optimizers are at work here. Looks
> like the "old" processors got left out.

Well, the DDK compiler is a separate compiler for each and every
architecture. Thus, it is not surprising if there are different
outcomes.


[using cdq and idiv]

>> Well, the MS compiler used them.
>>
> And it's still not impressing me. :-)

BTW: The code from gcc used cltd. Is it really better than cdq?


>> Anyway, is a DIV really so costly? I always thought that newer
>> processors recognize if I try to divide by a power of two and are
>> really fast in this case.
>>
>
> That would be news to me, but it's possible.

I looked around the web, but I could not find any mentioning of this.
Thus, I might have been confused here a little. ;)


> We're now at a point where only benchmarks could prove the definite
> advantage of one piece of code over another, and we'd need to run them
> on multiple platforms...

Yes, this is for sure. But I doubt it will make much sense here for us.


Regards,
Spiro.

--
Spiro R. Trikaliotis http://cbm4win.sf.net/
http://www.trikaliotis.net/ http://www.viceteam.org/

.

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