[PATCH] D11880: AMDGPU/SI: Only look at live out SGPR defs

[Matt Arsenault via llvm-commits]

arsenm added a comment.

In http://reviews.llvm.org/D11880#220688, @tstellarAMD wrote:

> It doesn't look like phab picked up your email response, so I'm reproducing it here:
>
> > I’m not sure I see why. vreg0 is live out of the entry block, so it will have it’s range extended until after the endif, so I don’t think it can be assigned to the same register as vreg1
>
>
> Ok, so you are saying this won't be a problem as long as we correctly extend the live range of vreg0.  That makes sense.  I would like to test this patch before it is committed.


In this example the live range of vreg1 wouldn't have been changed anyway because the if block only has one successor. I don't think this patch actually changes the insertion behavior.


http://reviews.llvm.org/D11880