RFR(S): 8213419: C2 may hang in MulLNode::Ideal()/MulINode::Ideal() with gcc 8.2.1

[Roland Westrelin]

>> http://cr.openjdk.java.net/~roland/8213419/webrev.01/

That one doesn't compile on windows. I have to make the following
changes so it goes through the submit repo:

http://cr.openjdk.java.net/~roland/8213419/webrev.01-02/

full webrev:

http://cr.openjdk.java.net/~roland/8213419/webrev.02/

Roland.