Subject: Re: ARM ELF toolchain patches
To: Ben Harris <bjh21@netbsd.org>
From: Philip Blundell <pb@futuretv.com>
List: port-arm32
Date: 02/22/2001 15:40:46
In message <Pine.SOL.4.21.0102221434000.1562-100000@draco.cus.cam.ac.uk>, Ben H
arris writes:
>Argh! I thought the whole point of moving to 32-bit padded structures was
>because that was what the ARM ABI specified. Have they changed things
>recently,
Not all that recently but yes, I gather this is what has happened. (The ADS
now uses 8-bit alignment whereas the old SDT used 32-bit.) I think the small
performance gain turned out not to be worth the portability hassles; I also
have a feeling some embedded users were upset at the waste of memory.
I don't know if this is actually spelled out in any published documentation;
I'm pretty sure it's not in either the ATPCS or the ARM ELF EABI
specifications. The ARM EABI unification effort seems to have faltered in
recent months, apparently due to lack of time.
p.