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Branching with Altivec comparisons

I was reading the PowerPC instruction reference that comes with Shark and it says that the Altivec comparison instructions (e.g. vcmpeq*, vcmpgt*, vcmpge*, etc.) set the CR6 part of the condition register. I take it this means that it's possible to use conditional branch instructions with Altivec comparisons.

Is there any way to do this using the GCC Altivec intrinsics instead of resorting to assembly? For example, something similar to:
if (vec_cmpeq(v1, v2)) {
// do something ...
} else {
// do something else ...
}
If so, can it be combined with GCC specific functions like __builtin_expect?

I realise it's usually better to write branchless code with vec_sel, etc.



r i c k
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