[ECOS] Re: Ecos Port to PPC509/PPC555

[Jonathan Larmour <jlarmour at cygnus dot co dot uk>]

Bart Veer wrote:
> 
> >>>>> "Jifl" == Jonathan Larmour <jlarmour@cygnus.co.uk> writes:

>     Jifl> But you can't rely on FP exceptions being generated - they
>     Jifl> don't for normal code, so I don't believe this is a viable
>     Jifl> option unless I've misunderstood you.
> 
> On some architectures including the PPC (if I remember correctly), it
> is possible to disable the floating point unit. The first operation
> that attempts to access the floating point unit, even if it is just to
> access a floating point register, will cause a hardware exception.
> This is separate from normal floating point exceptions such as
> overflow.

Oops yes. I did misunderstand you :-). For what its worth, MIPS and x86 have
this as well IIRC.

Jifl
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