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Re: Byte swapping support

> Was this considered significantly more complex because of the need to
> discriminate between native and reverse order? Or do you expect similar
> complexity even if this is not required (see my comment below)?

The former.

> I don't. The idea is to reverse scalar storage order for the whole
> userspace process and then add byte swapping to the Linux kernel when
> accessing userspace memory. This keeps userspace memory consistent
> with regards to endianness, which should lead to high compatibility
> with big-endian applications. Userspace memory access from the kernel
> always uses a small set of helper functions, which should make it
> easier to insert byte swapping at appropriate places.

Well, if your userspace is entirely in reverse order, then of course things 
are totally different and I suspect that you'll pay the price in term of run 
time performance.  This is not what the attribute was designed for, although 
we added the -fsso-struct switch at some point.

Eric Botcazou

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