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Re: Conflicting IRA patches

Jeff Law wrote:
On 07/07/10 14:35, Bernd Schmidt wrote:

Yes. As long as we have something for which we can compute
{max,min}_nregs, it should be OK - if these numbers are both 2, then
allocate two objects.
OK. I'll put these concerns aside and trust we'll get the details sorted out.

I was more worried about coalesce_allocnos, but it seems Vlad's patches
even remove some of the headaches I've had with that. I'm not sure yet
how to deal with the new left_conflicts_size mechanism.
I hadn't gotten this far -- I was just starting to look at the patches and saw that there were likely significant conflicts that we were going to need to work through and figured we needed to open a discussion.

Some of the speedup patches maybe could have gone into trunk directly
instead of a branch; that would have eliminated some sources of divergence.
Yea. I approved one which looked like it could go in independently right now. I looked at the others and they probably could go in with some relatively minor massaging.

My temptation is to place priority on the double-word stuff & speedups to reduce the amount of divergence we're dealing with, then sort through the issues the removal of cover classes introduces.


I checked Bernd's patch on SPEC2000 on x86 (32-bit modes) last week. Code of few benchmarks changed (only vpr, gcc, crafty, parser, eon, vortex, mesa, facerec, sixtrack, apsi). The codes size for SPECINT2000 was improved by 0.03% with patch and code size for SPECFP2000 was worsen by 0.006%. There is no visible improvement/degradation on changed benchmarks. Compilation time increase was quite insignificant (less than 0.2%). So as I wrote Ken Zadeck two years ago who tried to solve the problem for the old RA, the complexity of the problem solution does not justify
the solution benefits.

As for patch priority for checking in, I think you are right especially if we take that I have a branch for my work and Bernd does not have one and resolution of the conflicts could be done on ira-improv branch.

By the way, there is already another big conflict with recent Richard Sandiford's patches. Although it is a smaller conflict in comparison with one of Bernd's and my patches.

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