[YLUG] Why is this so much faster on an Opteron?

[Robert Hulme]

AHA

trueman% ./flags.sh
-march=pentium4 -mfpmath=sse -msse3
trueman% gcc -O3 -march=pentium4 -mfpmath=sse -msse3 hello1.cpp -o hello1-fast
trueman% time ./hello1-fast
./hello1-fast  2.90s user 0.00s system 99% cpu 2.911 total


flags.sh is http://www.pixelbeat.org/scripts/gcccpuopt



OK it looks like it's the SSE that is making the difference... does
the Opteron et all convert the normal instructions in to SSE ones at
runtime or something?

-Rob

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No offence Apu, but when they were handing out religions, you musta
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