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PowerPC FP handling weakness.



Eric Valette <valette at crf.canon.fr> writes:

[...]
> Why don't you send a patch that does deffered FPU registers saving... In
> that case enabling FP by default is a non problem since if a task does
> not use the FPU registers they will not be saved on context switch just
> when a flotating point execption processing occurs because FPU usage has
> been disabled...

I believe that there is no need for such a patch because RTEMS supports
deferred FPU registers saving for a long time. The problem is that current
'printf' implementation does use FP, and it will cause problems when you call
'printf' from non-FP task. Enabling FP bit in MSR for non-FP task just hides
the problem and doesn't solve it. Or maybe I don't understand what you are
saying?

BR,
Sergei Organov.