Re: [rfc] stack alignment macro cleanup

[Paul Brook <paul at codesourcery dot com>]

> > Your proposal doesn't make this problem any worse, if anything it's
> > better because we don't have to device between S_B and
> > PREFERRED_STACK_BOUNDARY. I'm just noting that documenting this as a
> > hardware property is at best misleading.
> 
> Well, I'm hoping to document that it *is* a hardware property, and
> remove some of the code that confuses it with an ABI property.
> There's some of that even within the x86 backend, where the Win64
> bits are wrong.

So the 8-byte ABI requirement should be described by I_S_B?
Does/should/will this also DTRT for the outgoing stack pointer (combined with 
__builtin_alloca, etc)?

If so your proposal seems OK from an ARM backend perspective. The conversion 
may be nontrivial, but the end result sounds better.

In theory these values can be per-function, but I'm happy to ignore that.

Paul