Re: [Sablevm-developer] SableJIT/x86 outperforms SableJIT/ppc!

[Grzegorz B. P. <ga...@de...>]

W li=B6cie z =B6ro, 03-03-2004, godz. 17:09, David B=E9langer pisze:=20
> On Tue, Mar 02, 2004 at 10:58:06PM -0500, Grzegorz B. Prokopski wrote:
> > W li?cie z wto, 02-03-2004, godz. 17:26, David B=E9langer pisze:=20
> > > Some results here:
> > > http://www.sable.mcgill.ca/~dbelan2/sablejit/results_2004-03-02.htm=
l
> > Hmm... It may sound strange, but how come that on x86 you got inlined
> > faster on all benchmarks than direct? I had some serious problems
> > with it lately. What _exact_ compiler version did you use?
> > (I might be wrong, but I think you stopped doing upgrades of SID at
> > some point, is that so?)
> >=20
> I am using:
> gcc-3.3 (GCC) 3.3.3 20040110 (prerelease) (Debian)
>=20
> I always got better results with inlined than direct on my AMD.

That's interesting. Here I have:
$ gcc --version
gcc (GCC) 3.3.3 (Debian)

$ dpkg -l gcc-3.3
ii  gcc-3.3        3.3.3-1        The GNU C compiler

> > Could you run sablecc on direct and inlined you compiled (x86 only)
> > and send me these two numbers? (this is my favorite test case where
> > the problem is visible)
> >=20
> yes, I will do it either later tonight or tomorrow.

Please do it as soon as you can. There's some (black) magic happening
here and I need every _sure_ starting point I can have.

I haven't found out yet how to effectively downgrade gcc. Last time
I did it - it was segfaulting while compiling sablevm. I'll try now
again.

The intersting thing is. In your version you compile only inlined
with -fno-block-reorder. I wonder whether there's some actual speed
penalty in the _speedup factor_ between direct and inlined as compared
to the Etienne's thesis. It'd be a major problem dropping this option
right now because in newer gcc, w/o this option it seems to move the
INLINED_END label _above_, _before_ the INLINED_START label...

I think some of your tests overlap w/ Etienne's. I'll check it.

> I will not have much time for major improvements in the next few months=
,
> I have a master thesis to start writing ASAP. :)

Ah, always this paperwork! 8)

				Grzegorz B. Prokopski

--=20
Grzegorz B. Prokopski <ga...@de...>
Debian GNU/Linux      http://www.debian.org
SableVM - LGPLed JVM  http://www.sablevm.org
Why SableVM ?!?       http://devel.sablevm.org/wiki/WhySableVM