review (XS) for 6969586: OptimizeStringConcat: SIGSEGV in LoadNode::Value()

[Vladimir Kozlov]

Looks good.

Vladimir

Tom Rodriguez wrote:
> http://cr.openjdk.java.net/~never/6969586
> 
> 6969586: OptimizeStringConcat: SIGSEGV in LoadNode::Value()
> Reviewed-by:
> 
> The logic in memnode that tries to constant fold loads from constant
> Strings doesn't handle a NULL base properly leading to a SEGV.  The
> fix is to test if the type is a really a constant TypeOopPtr instead
> of testing that the node is a ConP.  Tested with failing CTW test
> case.