On 12/13/2017 07:34 AM, Tom de Vries wrote:
On 10/16/2017 10:38 PM, Vladimir Makarov wrote:
This is another version of the patch to fix
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82353
The patch was successfully bootstrapped on x86-64 with Go and Ada.
Committed as rev. 253796.
Hi Vladimir,
AFAIU this bit of the patch makes sure that the flags register show up
in the bb_livein of the bb in which it's used (and not defined before
the use), but not in the bb_liveout of the predecessors of that bb.
I wonder if that's a compile-speed optimization, or an oversight.
Hi, Tom. It was just a minimal fix. I prefer minimal fixes for LRA
because even for me it is hard to predict in many cases how the patch
will affect all the targets. Therefore many LRA patches have a few
iterations before to be final.
I remember that I had some serious problems in the past when I tried to
implement fixed hard reg liveness propagation in LRA. It was long ago
so we could try it again. If you send patch you mentioned to gcc
mailing list, I'll review and approve it. But we need to be ready to
revert it if some problems occur again.
