On Wed, Mar 01, 2006 at 10:06:57PM +0100, Steven Bosscher wrote:
> On Wednesday 01 March 2006 21:49, H. J. Lu wrote:
> > It is the issue of quality of gcc 4.1 on IA32/x86-64. The current gcc
> > 4.1 performs very poorly on IA32/x86-64, comparing against gcc 4.2.
>
> Oh, really? Where are the numbers you have to support this, may I
> say, unlikely claim?
Here are diffs of SPEC CPU 2K between before and after with gcc 4.1
using "-O2 -ffast-math" on Nocona:
164.gzip 2.50%
175.vpr 1.55%
176.gcc -0.33%
181.mcf 0.85%
186.crafty 0.06%
197.parser 0.62%
252.eon 8.58%
253.perlbmk 2.75%
254.gap 0.66%
255.vortex 7.59%
256.bzip2 4.45%
300.twolf 21.11%
SPECint_base2000 4.04%
168.wupwise 39.10%
171.swim 38.88%
172.mgrid 61.64%
173.applu 37.62%
177.mesa 3.12%
178.galgel 27.13%
179.art 18.98%
183.equake 26.67%
187.facerec 0.35%
188.ammp 36.78%
189.lucas 3.52%
191.fma3d 42.71%
200.sixtrack 116.13%
301.apsi 32.75%
SPECfp_base2000 32.18%
> > This change
> > is specific to the IA32/x86-64 backend and won't affect any other
> > targets.
>
> Hmm... I thought Mark's message was pretty clear:
> http://gcc.gnu.org/ml/gcc-patches/2006-03/msg00060.html
> To quote:
> "The GCC 4.1 branch is now open, under the usual branch rules: fixes for
> regressions only."
>
The exception is the rule. We have done so on gcc 3.4 branch:
http://gcc.gnu.org/ml/gcc-cvs/2004-04/msg00775.html
H.J.
