gcc will become the best optimizing x86 compiler

[Agner Fog]

Michael Meissner wrote:
 >Memcpy/memset optimizations were added to glibc 2.8, though when your 
favorite
 >distribution will provide it is a different question:
 >http://sourceware.org/ml/libc-alpha/2008-04/msg00050.html

I finally got a SUSE with glibc 2.8. I can see that 32-bit memcpy has 
been modified with an extra misalignment branch, but no significant 
improvement. Glibc 2.8 is NOT faster than glibc 2.7 in my tests. It 
still doesn't use XMM registers.

Glibc 2.8 is still almost 5 times slower than the best function 
libraries for unaligned data on Intel Core 2, and the default builtin 
function is slower than any other implementation I have seen (copies 1 
byte at a time!).

Tarjei Knapstad wrote:
 >2008/7/26 Agner Fog <agner@agner.org>:
 >>I have libc version 2.7. Can't find version 2.8
 >It's in Fedora 9, I have no idea why the source isn't directly
 >available from the glibc homepage.

2.8 is not an official final release yet.