RFR (S): 7169782: C2: SIGSEGV in LShiftLNode::Ideal(PhaseGVN*, bool)

[Christian Thalinger]

Looks good.

-- Chris

On Jun 5, 2012, at 3:31 PM, Vladimir Ivanov <vladimir.x.ivanov at oracle.com> wrote:

> http://cr.openjdk.java.net/~vi/7169782/webrev.01/
> 
> During compilation, u0 in long_by_long_mulhi can become dead during interim transformations. It makes locally cached node pointer useless and the compiler crashes when trying to traverse node's dependencies. The fix is to artificially keep u0 node alive till the end of the graph construction using dummy hook node trick.
> 
> Also:
>  - did a cleanup: fixed lifetimes of other shared interim nodes to avoid similar problems in the future
>  - added a regression test for 6732154
> 
> Testing: VM regression tests
> 
> Thanks!
> 
> Best regards,
> Vladimir Ivanov