RFR(XS): 8232921: assert(is_object_aligned(result)) failed: address not aligned

[Schmelter, Ralf]

Hi Goetz,

the change looks good. Since you only check for != NULL anyway, the first implementation seems the most appropriate to me. It's small and obviously correct.

Best regards,
Ralf

-----Original Message-----
From: hotspot-runtime-dev <hotspot-runtime-dev-bounces at openjdk.java.net> On Behalf Of Lindenmaier, Goetz
Sent: Dienstag, 29. Oktober 2019 15:33
To: hotspot-runtime-dev at openjdk.java.net
Subject: [CAUTION] RFR(XS): 8232921: assert(is_object_aligned(result)) failed: address not aligned

Hi,

Originally, I wanted to model indicating that frames
have been dropped nicely in Java using
a meaningful java object. Exceptions in hidden frames
should be rare, so allocating only in that case should have
been cheap. Unfortunately, I can not allocate here.
Also, Boolean::TRUE is not necessarily initialized properly.

Actually, putting the modeling aside, I only need any legal
oop for this field. It is only tested for null later on.
So the most simple (and cheap) fix is just reusing
one of the oops in the array at hand.

So please review this fix.
http://cr.openjdk.java.net/~goetz/wr19/8232921-fix_hidden_frames/01/

I'll run it through our testing tonight.

Best regards,
  Goetz.