[cfe-commits] [patch] Make ARM NEON polynomial types unsigned

[Bob Wilson]

On Jan 14, 2013, at 10:04 AM, Tim Northover <t.p.northover at gmail.com> wrote:

>> This makes me a little nervous.  What do GCC and other
>> ARM compilers use?  If all the other ARM compilers use
>> unsigned poly types, then it is probably a good thing to
>> bring Clang in sync with them.
> 
> After a quick check, GCC chooses signed and ARMCC chooses unsigned.
> However, GCC also uses signed on AArch64 which is ABI-incorrect (I'll
> raise a ticket with them tomorrow).

What is the motivation for switching to unsigned?  If both GCC and Clang are using signed poly types, then I think they should stay that way unless there's a pretty compelling reason to fix it.

Is there something different about AArch64 that makes you want to diverge from the de facto standard for those types?  If not, it really sounds to me like it might be best to just switch everything (including your AArch64 ABI) to use signed poly types.