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Re: 3.0.1 performance

Kurt Garloff <> writes:

> On Fri, Aug 17, 2001 at 08:54:24AM -0400, Phil Edwards wrote:
> > The current limit /is/ 600, IIRC.  Perhaps the docs did not get updated,
>> or possibly you have outdated docs.  Are you looking at the online manual,
>> or the manual that shipped with 3.0?
> Don't think so:
> garloff@pckurt:/raid/egcs/gcc/doc $ cvs status invoke.texi
> ===================================================================
> File: invoke.texi       Status: Up-to-date
>    Working revision:
>    Repository revision:        /cvs/gcc/egcs/gcc/doc/invoke.texi,v
>    Sticky Tag:          gcc-3_0-branch (branch: 1.3.2)
> [...]
> garloff@pckurt:/raid/egcs/gcc/doc $ grep -A8 inline-limit invoke.texi 
> [...]
> @item -finline-limit=@var{n}
> @opindex finline-limit
> By default, gcc limits the size of functions that can be inlined.  This flag
> [...]
> number of pseudo instructions (not counting parameter handling).  The default
> value of @var{n} is 10000.  Increasing this value can result in more inlined code at
> [...]
> So the docu seems outdate. Anyway, I'd vote for upping the default based on
> the results posted. 1000 seems like a compromise. I'd personally vote for
> more (say 2500), as the value used to be much higher before (10k or 15k) and
> we do not want to risk too drastic changes between 3.0.0 and 3.0.1,
> do we?
Errr, yes, we want drastically better compile time.
The main reason 600 isn't good enough for some applications is that
our heuristics still aren't good.  Even using the one from integrate.c
does better. I have a patch that uses the one from integrate.c that should only
need 600 insns of inlining, but get alot better performance, at very small
compile time increase.

> Regards,
> -- 
> Kurt Garloff                   <>         [Eindhoven, NL]
> Physics: Plasma simulations  <K.Garloff@Phys.TUE.NL>  [TU Eindhoven, NL]
> Linux: SCSI, Security          <>    [SuSE Nuernberg, DE]
>  (See mail header or public key servers for PGP2 and GPG public keys.)

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