Re: nvptx offloading patches [3/n], RFD

[Jeff Law <law@redhat.com>]

On 11/01/14 05:57, Bernd Schmidt wrote:
> This is not against current trunk; it applies to gomp-4_0-branch where
> it is one of the necessary parts to make offloading x86->nvptx work. The
> issue is that the LTO file format depends on the machine_modes enum, it
> needs to match between host and offload target. The easiest way to do
> this is to just use the host-modes.def when compiling an offload compiler.
>
> Ports that want to be hosts for offloading may need to modify their
> modes.def. The patch below contains changes to i386-modes.def which
> modifies XFmode depending on a target switch. I'm not actually entirely
> sure what to do about this. Do we want to make this flag an error when
> offloading is enabled? Or maybe add float format support to the
> -foffload-abi option?
>
> Thoughts? Ok for the first part of the patch once the other offloading
> patches have gone in (bootstrapped and tested on x86_64-linux)?
It feels like we've got another real distinction to make.  We've had 
host, build & target and they're all independent.  It feels like we need 
offload target and better separate between target and offload target. 
Then we need to figure out the places where we've got bleed-out.

Not sure how to deal with this any further out than the immediate term 
than using a hack like this. Though I'd prefer to avoid the #ifdef as it 
seems to me this shouldn't be baked in at build/configure time.

jeff