RFR(M): 8223051: support loops with long (64b) trip counts

[Tobias Hartmann]

On 25.08.20 16:06, Tobias Hartmann wrote:
> Okay, thanks, I'll run some more testing with these values. Will report back once it finished.

All done.

Apart from expected test failures (TestIntVect due to failed vectorization and
UseCountedLoopSafepointsTest due to a missing safepoint) and unrelated/known issues, I'm seeing the
following failure:

compiler/loopopts/TestRangeCheckPredicatesControl.java
-server -Xcomp -XX:+IgnoreUnrecognizedVMOptions -XX:StressLongCountedLoop=200000000

#  SIGSEGV (0xb) at pc=0x00007fb970ac2b73, pid=2312839, tid=2312845

# Problematic frame:
# V  [libjvm.so+0x18b3b73]  ZMark::try_mark_object(ZMarkCache*, unsigned long, bool)+0x53

Current thread (0x00007fb968059260):  GCTaskThread "ZWorker#2" [stack:
0x00007fb96ea6c000,0x00007fb96eb6c000] [id=2312845]

Stack: [0x00007fb96ea6c000,0x00007fb96eb6c000],  sp=0x00007fb96eb64be0,  free space=994k
Native frames: (J=compiled Java code, A=aot compiled Java code, j=interpreted, Vv=VM code, C=native
code)
V  [libjvm.so+0x18b3b73]  ZMark::try_mark_object(ZMarkCache*, unsigned long, bool)+0x53
V  [libjvm.so+0x18b59a8]  ZMark::work_without_timeout(ZMarkCache*, ZMarkStripe*,
ZMarkThreadLocalStacks*)+0x148
V  [libjvm.so+0x18b6048]  ZMark::work(unsigned long)+0xa8
V  [libjvm.so+0x18f1b8d]  ZTask::GangTask::work(unsigned int)+0x1d
V  [libjvm.so+0x187a4c4]  GangWorker::run_task(WorkData)+0x84
V  [libjvm.so+0x187a604]  GangWorker::loop()+0x44
V  [libjvm.so+0x173ab90]  Thread::call_run()+0x100
V  [libjvm.so+0x143fc16]  thread_native_entry(Thread*)+0x116


Roland, could you please try to reproduce and check if it's related to your patch?

Best regards,
Tobias