On Mon, 14 Jan 2019 23:04:23 +0300 Alexey Dobriyan <[email protected]> wrote:

> Compilers like to transform loops like
> 
>       for (i = 0; i < n; i++) {
>               [use p[i]]
>       }
> 
> into
>       for (p = p0; p < end; p++) {
>               ...
>       }
> 
> Do it by hand, so that it results in overall simpler loop
> and smaller code.
> 
> Space savings:
> 
>       $ ./scripts/bloat-o-meter ../vmlinux-001 ../obj/vmlinux
>       add/remove: 0/0 grow/shrink: 2/1 up/down: 4/-9 (-5)
>       Function                                     old     new   delta
>       proc_tid_base_lookup                          17      19      +2
>       proc_tgid_base_lookup                         17      19      +2
>       proc_pident_lookup                           179     170      -9
> 
> Note: this trick bloats readdir, so don't do it :-\

I don't understand the Note:.  Can you please expand?

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