__switch_to test-and-branch ALTIVEC specific?

[Segher Boessenkool]

>> This probably has to due with what happens on a G4 system with a
>> kernel not build with Altivec.. However, I dont remember exactly what
>> behavior is desired.

A kernel not build with AltiVec support will just
SIGILL any user process that tries to use it (and
MSR[VEC] = 0).

The code here can safely be #ifdef'ed out (but note
I only looked at the code, I didn't test it ;-) )


Segher