arch.7: correct claim about ILP32 alignment

[brooks]

Summary

Only i386 lays out structures with weak (4-byte) alightment. It may be
that access works when weakly aligned, but from an ABI perspective, it's
all about struct layout.

Sponsored by: Innovate UK

[emaste]

Is this true for 32-bit powerpc as well?

[brooks]

In D52818#1206819, @emaste wrote:

Is this true for 32-bit powerpc as well?

From what I could tell in compiler explorer, yes.

[emaste]

I guess there's also 32-bit MIPS in 13 still, and this doc claims to apply to 13.0 and later unless otherwise noted. But it doesn't matter as MIPS has already been removed from all of the individual tables.

[brooks]

In D52818#1206838, @emaste wrote:

I guess there's also 32-bit MIPS in 13 still, and this doc claims to apply to 13.0 and later unless otherwise noted. But it doesn't matter as MIPS has already been removed from all of the individual tables.

It's also the case that mips32 strongly aligns 64-bit types. i386 is the odd one out.

[kib]

In D52818#1206828, @brooks wrote:

In D52818#1206819, @emaste wrote:

Is this true for 32-bit powerpc as well?

From what I could tell in compiler explorer, yes.

I looked at psABI, it is.