Help with JDK-8230525 - Adding new intrinsic

[Cesar Soares Lucas]

Hey there,

I'm working on JDK-8230525 (https://bugs.openjdk.java.net/browse/JDK-8230525)
and for the past few days I'm struggling to get all the plumbing necessary to add a
new intrinsic and instruction pattern for the Integer.reverse() method. Can someone
please look at the code I currently have and advise what I'm doing wrong/missing
here? The exact problem I'm struggling with is that C2 for some reason choose a
previously existing instruction pattern (as defined in x86_64.ad) instead of the new
instruction pattern I created.

I shared the code here: https://github.com/JohnTortugo/jdk/pull/1


Thanks,
Cesar