[RFR]: 8186461: zero: Don't use PowerPC FPU instructions on targets without FPU

[John Paul Adrian Glaubitz]

On 08/19/2017 11:22 AM, Andrew Haley wrote:
> That does not look right.  Surely we need an alternative
> implementation?

Those machines in question are usually single-CPU, so we probably
don't need any particular inline assembly to perform atomic copy
on these machines.

However, there are actually machines - I have two of these - which
have a dual-core configuration. So, using inline assembly to perform
the atomic operation might make sense here.

While these CPUs don't actually have an FPU, they have something
called SPE instructions which are some sort of FPU replacement.

I will have a closer look later to figure out whether I can find
something in the data sheet [1].

See [1] and [2].

Adrian

> [1] http://www.nxp.com/docs/en/reference-manual/E500CORERM.pdf
> [2] https://en.wikipedia.org/wiki/PowerPC_e500

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 .''`.  John Paul Adrian Glaubitz
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