[aarch64-port-dev ] Fwd: Compact strings enablement - JTreg runs

[Stuart Monteith]

Hello,
   I sent this to the wrong address by accident, and it hadn't bounced
- the autocorrect kicked in this time.

   With a view to enable compact strings by default, I've run JTreg
against a build from yesterday with "-XX:-CompactStrings" and
"-XX:+CompactStrings".

I get the following differences:


  0: JTwork-compactoff  pass: 5,840; fail: 1,793; error: 21; not run: 331
  1: JTwork-compacton  pass: 5,836; fail: 1,793; error: 25; not run: 331

  0      1      Test
  fail   pass   com/sun/jdi/InterruptHangTest.java
  pass   error  java/awt/Dialog/CloseDialog/CloseDialogTest.java
  fail   pass   java/awt/Graphics2D/DrawString/DrawStringCrash.java
  pass   error  java/lang/instrument/PremainClass/NoPremainAgentTest.java
  pass   fail
java/rmi/activation/Activatable/restartCrashedService/RestartCrashedService.java
  pass   fail
java/rmi/server/RMISocketFactory/useSocketFactory/unicast/UseCustomSocketFactory.java
  error  pass   java/util/ResourceBundle/modules/visibility/visibility.sh
  pass   fail   java/util/concurrent/tck/JSR166TestCase.java
  pass   error
java/util/stream/boottest/java.base/java/util/stream/SpinedBufferTest.java
  fail   pass   java/util/zip/EntryCount64k.java
  pass   error  sun/security/provider/SecureRandom/StrongSecureRandom.java
  pass   error  tools/launcher/ArgFileSyntax.java

  12 differences

Ideally there would be 0 failures and errors in both, but I'll check
to see what the differences were. Some of the names are suspicious,
others - such as concurrency tests - look like they have the potential
to have issues.

AFAICT, this is the only changed needed to make compact strings the default:
    hotspot/src/cpu/aarch64/vm/globals_aarch64.hpp
-- define_pd_global(bool, CompactStrings, false);
++ define_pd_global(bool, CompactStrings, true);

hasNegatives - please find attached my most recent results with my
hasNegatives intrinsic.  The vertical axis is time (logarithmic)
-lower is better. The horizontal axis is the number of characters
scanned before has_negatives returns true. I'm trying to even-out the
middle to lower side of the graph, as I expect has_negatives will trip
either early, or late.

Regards,
   Stuart