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Re: ppc multlibs and BSP removal was Re: powerpc altivec support



Ralf Corsepius <ralf.corsepius@rtems.org> writes:

> On Wed, 2005-02-09 at 19:40 -0800, Till Straumann wrote:
[...]
> PPC_HAS_DOUBLE is primarily used in task-switches, so I am wondering
> what PPC_HAS_DOUBLE actually means:
> * The CPU lack some (double) instructions, therefore requires a
> customized task-switch. Makes me wonder, what happens with GCC generated
> FPU code on these CPUs.
> * The CPU needs customization because it lacks a feature.

It means that CPU lacks both double registers and double instructions, I
think. I.e., FPU registers are 32 bits and single-precision instructions
should be used for load/store.

The only such CPU in RTEMS seems to be 602, but I've no idea if it's in
fact used/supported.

-- 
Sergei.