[rfc] removing -mpreferred-stack-boundary=2 flag for i386?

Bruce Evans brde at optusnet.com.au
Sat Dec 24 11:12:45 UTC 2011


On Sat, 24 Dec 2011, Alexander Best wrote:

> On Sat Dec 24 11, Bruce Evans wrote:
>> On Fri, 23 Dec 2011, Alexander Best wrote:
>>
>>> is -mpreferred-stack-boundary=2 really necessary for i386 builds any
>>> longer?
>>> i built GENERIC (including modules) with and without that flag. the results
>>> are:
>>
>> The same as it has always been.  It avoids some bloat.
>>
>>> 1654496	bytes with the flag set
>>> vs.
>>> 1654952	bytes with the flag unset
>>
>> I don't believe this.  GENERIC is enormously bloated, so it has size
>> more like 16MB than 1.6MB.  Even a savings of 4K instead of 456 bytes
>
> i'm sorry. i used du(1) to get those numbers, so i believe those numbers
> represent the ammount of 512-byte blocks. if i'm correct GENERIC is even
> more bloated than you feared and almost reaches 1GB:
>
> 807,859375  megabytes with flag set
> vs.
> 808,0820313 megabytes without the flag set

That's certainly bloated.  It counts all object files and modules, and
probably everything is compiled with -g.  I only counted kernel text
size.

Bruce


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