Comment # 29 on bug 90887 from Ilia Mirkin

(In reply to jr from comment #28)
> (In reply to Ilia Mirkin from comment #27)
> > If you're still having trouble, try building for a fermi or kepler target
> > using nouveau_compiler, i.e.
> > 
> > src/gallium/drivers/nouveau/nouveau_compiler -a c0 -
> > <paste the tgsi shader, ^D>
> > 
> > and enjoy. [It also can take it from a file.]
> 
> Nice, thanks for the hint. But it produces different code to your log
> (without any ld u64) and BB4 doesn't vanish. It seems to trigger edge
> splitting once on the 2 to 4 edge:

Hmmmm... maybe it was one of my local patches? I'll try to figure out what went
wrong later tonight.

I added logic to be clever about edge types... when splitting an edge, the type
should remain except a forward edge becomes a cross edge. (You can do it out on
paper...) Perhaps that upset things? It doesn't seem like codegen is using
those terms in the usual MST meanings :(