On Jan 15, 2009, at 11:31 AM, Dan Nelson wrote:
Actually, those functions are only enabled if the CPU is truly a 586-class processor. See /sys/i386/isa/npx.c , the npx_attach() function. There is a test for cpu_class==CPUCLASS_586, while most modern CPUs are CPUCLASS_686.
Thanks for the additional feedback, Dan. I remember some weirdness around things like the VIA C3 "Centaur" processors, which had CMOV feature and claimed to be a 686, but lacked SSE...not that those were an especially common case, but I still have one floating around.
I see 686- and SSE2-optimized pagezero routines in support.s, but I don't see equivalents for bzero, bcopy, and copyin/copyout. Is something like generic_bzero() faster on a 686-class CPU than i586_bzero() would be?
Regards, -- -Chuck _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[email protected]"
