I've added sysenter/sysexit support for all syscalls with up to 4
parameters.
The syscalls with 5 or 6 parameters must continue to use int $0x80, I
need 2 registers to pass the user space stack and instruction pointer
values. The sysenter instruction destroys them.

sysenter is supported by AMD K7 and Intel Pentium II and later.
Result: simple syscall (getpid()) more than 35% faster.

before: 295 cpu ticks
now: 186 cpu ticks.

patch attached, sample code on
http://colorfullife.com/~manfred/sysenter

syscall support for K6/2 is not planned :-(

--
	Manfred