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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Mon, 25 Jul 2016 10:51:37 +1000
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Subject: Re: [Qemu-devel] TCG problem with cpu_{st,ld}x_data ?
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To: Richard Henderson <rth@twiddle.net>, qemu-devel@nongnu.org
Cc: Paolo Bonzini <pbonzini@redhat.com>, Christian Borntraeger <borntraeger@de.ibm.com>

On Mon, 2016-07-25 at 10:46 +1000, Benjamin Herrenschmidt wrote:
> On Mon, 2016-07-25 at 06:06 +0530, Richard Henderson wrote:
> >=20
> > These functions would have to be always_inline for this to work.=C2=A0
> > Otherwise you=C2=A0
> > could get the helper's PC, not the TCG caller's PC.
> >=20
> > But let's try to fix this the other way.
>=20
> I could use some help there as I don't really understand the PC fixup
> adjustment mechanism in qemu...=C2=A0

One thing I can do, but I don't know whether that's worthwhile (you
tell me), is change all translation helpers in powerpc to do like
x86, which is to pass the RA along and never use the non_ra() variants.

But that's quite a bit of churn, so let me know if your plan is better.

Are those functions always meant to be called within translation
helpers ? IE, the fault can safely longjmp out and it's just a matter
of finding the proper instruction PC to report ?

Or can they also be called outside of that context ?

Cheers,
Ben.