> > 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