Re: AMD GCN port

[Andrew Stubbs <ams at codesourcery dot com>]

On 11/05/18 10:26, Richard Biener wrote:
> Sounds good but I'd not do 1. given the github repo can serve as archiving
> point, too.  Having 2. doesn't sound too useful over 3. so in the end I'd
> do only 3. and 4.  Of course 1 and 2 might help you in doing 3 and 4.

Indeed, I've been worried that I'm basically planning to expose internal 
steps.

The problem I'm trying to solve with 2 is that what I need is 3, but 
that means code dependencies on things I don't own, which makes it 
harder to get to 4.


The other thing that's occurred to me is that with og8 being new, maybe 
it's a good time to merge the GCN stuff into that, and work with the 
NVidia folks to share it. [Adding Cesar and Thomas to CC.] I'm aware of 
some incompatibilities with og7, but those are going to need fixing 
either way.

Here's another proposal.

trunk
 |\
 | gcc-7-branch
 | |\
 | : gcn-gcc-7-branch (1 - possibly notional)
 |                 \
 |\                 |
 | gcc-8-branch     |
 | |\              /
 | | gcn-gcc-8-branch (2. trunk compatible)
 | |       |       '----------------------------.
 | |\      |                                    |
 | : openacc-gcc-8-branch (3. share existing)   |
 |                                              |
 |\  ,------------------------------------------'
 | gcn (4. temporary)
 |/
gcc-9


Obviously, the description "trunk compatible" would become less true 
over time, but it will be less diverged than og8. I suppose this branch 
could also be notional, only named internally, though?

I guess it makes no difference to me -- I'm going to have to go through 
all the steps anyway -- but it depends how transparent others would like 
me to be.

Andrew