[LLVMdev] Contributing the Apple ARM64 compiler backend

[Eric Christopher]

On Fri, Mar 28, 2014 at 2:37 PM, Chandler Carruth <chandlerc at google.com> wrote:
>
> On Fri, Mar 28, 2014 at 2:31 PM, Hal Finkel <hfinkel at anl.gov> wrote:
>>
>> ----- Original Message -----
>> > From: "Tim Northover" <t.p.northover at gmail.com>
>> > To: "Renato Golin" <renato.golin at linaro.org>
>> > Cc: "LLVM Developers Mailing List" <LLVMdev at cs.uiuc.edu>
>> > Sent: Friday, March 28, 2014 3:47:49 PM
>> > Subject: Re: [LLVMdev] Contributing the Apple ARM64 compiler backend
>> >
>> > Hi Renato,
>> > >> 2. Test it. Benchmark it. Explore it. Get data for the community
>> > >> to work with about the state of the back end. ARM has some
>> > >> excellent data that will help guide us here.
>> > >
>> > > Count me in. Would that be a different triple? arm64-linux-gnu?
>> >
>> > Yep. "--target arm64-linux-gnu" should behave basically the same as
>> > aarch64-linux-gnu, except ending up in the ARM64 backend. Complete
>> > with the usual issues of finding your toolchain's includes & libs;
>> > we've not solved that.
>>
>> Is a different target triple the right thing to do here? I think that
>> would introduce a ton of user confusion. How about we keep the target
>> triples as they are, and add some other way to choose the desired backend?
>
>
> I share your concern. However, I suspect that a) we will always have at
> least an alias as both triples are probably in use at this point, and b) it
> won't be the end of the world to have two triples for the same arch long
> term. amd64 and x86_64 wasn't the end of the world either. ::shrug::
>

I agree here, I'd prefer not to have to switch on and off various backends.

-eric