Request for reviews (S): 6889300: assert(i != k || is_new || i->outcnt() > 0, "don't return dead nodes")

[Tom Rodriguez]

Looks good.

tom

On Oct 9, 2009, at 8:48 AM, Vladimir Kozlov wrote:

>
> http://cr.openjdk.java.net/~kvn/6889300/webrev.00
>
> Fixed 6889300: assert(i != k || is_new || i->outcnt()  > 0, "don't  
> return dead nodes")
>
> Problem:
> Customer hit this assert in transform_old() when
> PhiNode::Ideal() method returns Phi node with no users
> when before the Ideal() call it only references itself
> with the edge corresponding to the dead control path.
>
> Solution:
> Return TOP for such case if it is IGVN transformation.
> Add verification that during IGVN new Phi nodes should
> be hooked before calling transform(). We need this
> restriction to catch dead paths. The only place
> which missed it was split_if() and I fixed it.
>
> Reviewed by:
>
> Other testing:
> JPRT, CTW, NSK
>