Re: [harder@ifa.au.dk: Speed of all-completions]

[Andreas Schwab <schwab@suse.de>]

David Kastrup <dak@gnu.org> writes:

> Andreas Schwab <schwab@suse.de> writes:
>
>> David Kastrup <dak@gnu.org> writes:
>> 
>> > Andreas Schwab <schwab@suse.de> writes:
>> >
>> >> This is due to this change:
>> >> 
>> >> 	(Ftry_completion, Fall_completions, Ftest_completion): Bind
>> >> 	case-fold-search to the value of completion-ignore-case when
>> >> 	checking completion-regexp-list.
>> >> 
>> >> I've checked in a fix that avoids the overhead of specbind when
>> >> completion-regexp-list is empty.
>> >
>> > At the cost of being more expensive when it isn't.
>> 
>> Why is it more expensive?  The check for CONSP (completion-regexp-list)
>> has to be done anyway, and can be CSE'd by the compiler.
>
> Because you are redoing the binding for every element in the loop,
> while it is needed only once.

I did not change anything in this regard.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux AG, Maxfeldstraße 5, 90409 Nürnberg, Germany
Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."