RFR(S): 8058461: serviceability/dcmd/CodelistTest.java and serviceability/dcmd/CompilerQueueTest.java SIGSEGV

[Nils Eliasson]

Hi,

I would like review of this change that includes three fixes:

1) Let Dcmd Compiler.codelist only print alive-nmethods. We ran into 
crashes when listing zombies and unloaded too. Alive nmethods includes 
not-entrants so it still gives a pretty good idea about whats in the 
code cache and what has been used recently.

2) Take CompileQueue lock when printing queue. It is not enough to be at 
a safepoint - the compiler threads may still mutate the list causing 
crashes.

3) Relax the parsing of long hex-numbers in the test of codelist. High 
addresses (sparc) casues NumberFormatExceptions.

bug: https://bugs.openjdk.java.net/browse/JDK-8058461
webrev: http://cr.openjdk.java.net/~neliasso/8058461/webrev.04/

Thanks!
//Nils