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Re: Unit at time compilation mode II


> > On Tuesday, February 11, 2003, at 02:17 AM, Zack Weinberg wrote:
> > >(That would entail that unit-at-a-time compilation was mandatory,
> > >which I think should be just fine particularly if we can knock down
> > >the size of DECL nodes a bit.)
> > 
> > I hope this doesn't have a negative compilation speed impact on a small 
> > (128M) machine on real code, either by itself, or in conjunction with 
> > pch.
> 
> I've sent some analysis of it earlier to the list.  In the current form
> it brings about 1% speedup on i386 with -O2 (so no inlining, just
						  ^^
I now do inline functions called exactly once even at -O2.  It is about
1.3rd of the speedup.  That part is target indpendent.
I don't do inlining of small functions as -O3 does.  With -O3 the
comparsion is more dificult, since patch enabled backward inlining thus
larger (and likely faster) programs are produced at -O3 leading to
slowdown of compiler as it has more code to get over.  The slowdown is
proportional to code size growth.

Honza


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