Some additional tests :<br><br>With : -O2 -march=core2 for both gcc and llvm-gcc : LLVM is better with 10%.<br><br> LLVM GCC Difference Difference %<br><br> Run 1 13771597.2 13105010.6 666586.6 4.84<br>
Run 2 13813420.8 12536327.1 1277093.7 9.25<br> Run 3 13769573.8 12124207.3 1645366.5 11.95<br> Run 4 13883222.6 12794159.1 1089063.5 7.84<br> Run 5 13890414.6 12105946 1784468.6 12.85<br>
Run 6 13784627.3 11648245 2136382.3 15.5<br> Run 7 13920748.9 11781692.4 2139056.5 15.37<br> Run 8 13816843.9 12460451.3 1356392.6 9.82<br> Run 9 13864682.1 12959671.4 905010.7 6.53<br>
Run 10 13849863.4 12964021.5 885841.9 6.4<br><br> Average 13836499.46 12447973.17 1388526.29 10.03<br> Standard deviation 53189.13 515638.56 522400.98 3.77<br>
<br><br><br>With : -O3 -march=core2 for both compiler : GCC is better with 5.75%<br><br> LLVM GCC Difference Difference %<br><br> Run 1 13790728.3 14902550.9 -1111822.6 -8.06<br>
Run 2 13840499.3 14759093.2 -918593.9 -6.64<br> Run 3 13975018.5 14545983.5 -570965 -4.09<br> Run 4 13853799.5 15126446.4 -1272646.9 -9.19<br> Run 5 13993633.5 14824100.4 -830466.9 -5.93<br>
Run 6 13903645.3 12768793.8 1134851.5 8.16<br> Run 7 13816401.7 15003783.8 -1187382.1 -8.59<br> Run 8 13735232.8 14976854.3 -1241621.5 -9.04<br> Run 9 13902380.7 14778159.5 -875778.8 -6.3<br>
Run 10 13936761.8 15022553.5 -1085791.7 -7.79<br><br> Average 13874810.14 14670831.93 -796021.79 -5.75<br> Standard deviation 82443.34 688446.69 712123.9 5.14<br>
<br><br>Olivier.<br><br><br><br><br><br><div class="gmail_quote">2009/9/16 Török Edwin <span dir="ltr"><<a href="mailto:edwintorok@gmail.com">edwintorok@gmail.com</a>></span><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div class="im">On 2009-09-16 11:42, Olivier Meurant wrote:<br>
> On Tue, Sep 15, 2009 at 5:35 PM, David Greene <<a href="mailto:dag@cray.com">dag@cray.com</a><br>
</div><div><div></div><div class="h5">> <mailto:<a href="mailto:dag@cray.com">dag@cray.com</a>>> wrote:<br>
><br>
><br>
> Remember, the goal here isn't to show how great LLVM is. It's to<br>
> get an<br>
> honest assessment of where we are at. Phoronix did us a big<br>
> favor. Getting<br>
> more details about his tests would help us even more.<br>
><br>
><br>
> It's exactly what I'm trying to do. I'm not even a LLVM contributor,<br>
> so I don't feel responsible for a good or bad performances of LLVM. :)<br>
> Anyway, thanks for pointing this target differences. After some hours<br>
> at recompiling gcc, here we are :<br>
><br>
> Some information on the test platform :<br>
><br>
> cat /etc/lsb-release<br>
> DISTRIB_ID=Ubuntu<br>
> DISTRIB_RELEASE=9.04<br>
> DISTRIB_CODENAME=jaunty<br>
> DISTRIB_DESCRIPTION="Ubuntu 9.04"<br>
><br>
> uname -a<br>
> Linux zaraki 2.6.28-15-generic #49-Ubuntu SMP Tue Aug 18 18:40:08 UTC<br>
> 2009 i686 GNU/Linux<br>
><br>
> /proc/cpuinfo<br>
> dual core Intel(R) Core(TM)2 CPU X6800 @ 2.93GHz (cache size 4096)<br>
><br>
> llvm-gcc -v<br>
> Using built-in specs.<br>
> Target: i686-pc-linux-gnu<br>
> Configured with: ../llvm-gcc4.2-2.5.source/configure<br>
> --prefix=/mounts/zion/disks/0/localhome/tbrethou/2.5/prerelease2/llvm-gcc/obj/../install<br>
> --program-prefix=llvm-<br>
> --enable-llvm=/localhome/tbrethou/2.5/prerelease2/llvm-2.5/<br>
> --disable-bootstrap --enable-languages=c,c++,fortran<br>
> Thread model: posix<br>
> gcc version 4.2.1 (Based on Apple Inc. build 5636) (LLVM build 2.5)<br>
> (Binary from official x86 2.5 release)<br>
><br>
> gcc -v<br>
> Using built-in specs.<br>
> Target: i686-pc-linux-gnu<br>
> Configured with: ./configure --prefix=/usr/local<br>
> Thread model: posix<br>
> gcc version 4.4.1 (GCC)<br>
<br>
</div></div>Phoronix tested with gcc 4.2.1 (Apple's).<br>
<div class="im"><br>
><br>
> The compilation line are :<br>
> gcc -o bin src.c -O3<br>
> llvm-gcc -o bin src.c -O3<br>
<br>
</div>The Makefile uses -O by default, perhaps that is what Phoronix used too.<br>
<div class="im"><br>
><br>
><br>
> Results :<br>
> LLVM average : 13553161.95<br>
> gcc average : 14624441.45<br>
> Average : gcc is better with 8%<br>
><br>
> The full report :<br>
> "LLVM" "GCC" "Difference" "Difference %"<br>
><br>
> "Run 1" 13842616 14693115.8 -850499.8 -6.14<br>
> "Run 2" 13773202.9 14785734.9 -1012532 -7.35<br>
> "Run 3" 13671309.3 14985114 -1313804.7 -9.61<br>
> "Run 4" 12916939 14640392.9 -1723453.9 -13.34<br>
> "Run 5" 13572133.3 14425575 -853441.7 -6.29<br>
> "Run 6" 13810096.5 14694240.6 -884144.1 -6.4<br>
> "Run 7" 13427435.8 14695094.6 -1267658.8 -9.44<br>
> "Run 8" 14056659.9 14468968.4 -412308.5 -2.93<br>
> "Run 9" 13699125.3 14373360.9 -674235.6 -4.92<br>
> "Run 10 12762101.5 14482817.4 -1720715.9 -13.48<br>
><br>
> "Average" 13553161.95 14624441.45 -1071279.5 -7.99<br>
> "Standard deviation" 412810.77 187898.68<br>
> 430895.31 3.46<br>
><br>
> Is there again something wrong on this test ?<br>
<br>
</div>No, it seems fine.<br>
<br>
I get different results on x86-64 though (with -O), the difference is<br>
very small (4% with 3% stddev, or 3% with 1.5% stddev).<br>
<br>
Maybe you should try to reproduce one of the other benchmarks that show<br>
a higher difference, according to phoronix JOhn the Ripper shown 40%<br>
performance drop, there was also a huge drop for blowfish.<br>
<br>
<br>
<br>
GCC 4.4.1 GCC 4.2.4 LLVM-GCC 2.5 LLVM-GCC 2.6 GCC-4.4/LLVM2.5<br>
GCC-4.4/LLVM2.6 GCC-4.4/GCC-4.2<br>
<br>
144663277 139072037 154747143 151467440 0.935 0.955 1.040<br>
<br>
144413249 139042455 150949846 150322055 0.957 0.961 1.039<br>
<br>
144915166 138131283 150630261 150650540 0.962 0.962 1.049<br>
<br>
145602711 138587982 154993781 147281539 0.939 0.989 1.051<br>
<br>
145547868 139224734 150650813 147998859 0.966 0.983 1.045<br>
<br>
145719970 139224734 144055081 152474829 1.012 0.956 1.047<br>
average 145143706.83 138880537.5 151004487.5 150032543.67 0.962<br>
0.968 1.045<br>
stdev 551855.54 435155.79 3961926.31 2009642.82 0.027 0.015 0.005<br>
<br>
<br>
Using built-in specs.<br>
Target: x86_64-linux-gnu<br>
Configured with: ../src/configure -v --with-pkgversion='Debian 4.4.1-4'<br>
--with-bugurl=file:///usr/share/doc/gcc-4.4/README.Bugs<br>
<div class="im">--enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr<br>
</div>--enable-shared --enable-multiarch --enable-linker-build-id<br>
<div class="im">--with-system-zlib --libexecdir=/usr/lib --without-included-gettext<br>
</div>--enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.4<br>
--program-suffix=-4.4 --enable-nls --enable-clocale=gnu<br>
--enable-libstdcxx-debug --enable-mpfr --enable-objc-gc<br>
--with-arch-32=i486 --with-tune=generic --enable-checking=release<br>
--build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu<br>
Thread model: posix<br>
gcc version 4.4.1 (Debian 4.4.1-4)<br>
<br>
llvm2.5:<br>
Using built-in specs.<br>
Target: x86_64-unknown-linux-gnu<br>
Configured with: ../llvm-gcc-4.2/configure --program-prefix=llvm-<br>
--enable-llvm=/home/edwin/llvm2.5/obj --enable-languages=c,c++,fortran<br>
Thread model: posix<br>
gcc version 4.2.1 (Based on Apple Inc. build 5636) (LLVM build)<br>
<br>
llvm2.6pre1:<br>
Using built-in specs.<br>
Target: x86_64-unknown-linux-gnu<br>
Configured with: ../llvm-gcc4.2-2.6.source/configure<br>
--program-prefix=llvm- --enable-languages=c,c++,fortran<br>
--enable-llvm=/home/edwin/llvm2.6/obj/<br>
Thread model: posix<br>
gcc version 4.2.1 (Based on Apple Inc. build 5649) (LLVM build)<br>
<br>
Using built-in specs.<br>
Target: x86_64-linux-gnu<br>
<div class="im">Configured with: ../src/configure -v<br>
</div><div class="im">--enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr<br>
--enable-shared --with-system-zlib --libexecdir=/usr/lib<br>
--without-included-gettext --enable-threads=posix --enable-nls<br>
</div>--with-gxx-include-dir=/usr/include/c++/4.2 --program-suffix=-4.2<br>
<div class="im">--enable-clocale=gnu --enable-libstdcxx-debug --enable-objc-gc<br>
</div>--enable-mpfr --with-tune=generic --enable-checking=release<br>
--build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu<br>
Thread model: posix<br>
gcc version 4.2.4 (Debian 4.2.4-6)<br>
<br>
<br>
Best regards,<br>
<font color="#888888">--Edwin<br>
<br>
</font></blockquote></div><br>