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On Sat, Dec 02, 2017 at 11:23:10PM -0800, Manuel McLure wrote |
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> Here's the situation. I have a system that's been running for many years |
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> with an Athlon 5050e processor. The system is built with |
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> |
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> CFLAGS="-march=k8-sse3 -O2 -pipe -msse3" |
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> CPU_FLAGS_X86="3dnow 3dnowext mmx mmxext sse sse2 sse3" |
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> |
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> I have the possibility of upgrading the system to a first-generation |
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> Intel Core i5 which should give a nice speed boost, but of course the |
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> Intel chip doesn't understand 3dnow or 3dnowext, so I'll have to do |
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> a system rebuild before I switch out the motherboard/processor. It |
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> seems pretty obvious that I have to take "3dnow 3dnowext" out of |
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> CPU_FLAGS_X86, but what CFLAGS would be recommended for a system |
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> that will still run with the AMD processor but won't fall over when |
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> I switch to the Intel processor? Once I have the Intel in place I |
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> can rebuild with options more suited for that chip, but I want to |
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> make sure I don't end up in a catch-22 situation. |
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|
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https://gcc.gnu.org/onlinedocs/gcc-6.4.0/gcc/x86-Options.html#x86-Options |
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lists what instruction sets gcc expects for any "-march=<whatever>" |
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|
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I would suggest rebuilding with... |
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|
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CFLAGS="-march=nocona -O2 -pipe" |
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CPU_FLAGS_X86="mmx sse sse2 sse3" |
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|
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nocona was the first Intel cpu to support AMD64 instructions, and it's |
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the newest Intel that does not exceed your AMD. The next Intel cpu, the |
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"core2" supports ssse3 which your AMD does not (count the "s"'s... very |
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carefully; sse3 != ssse3). |
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|
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-- |
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Walter Dnes <waltdnes@××××××××.org> |
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I don't run "desktop environments"; I run useful applications |