Heads-up: jdk/jdk CTW test failures

[Aleksey Shipilev]

Lots of CTW failures in jdk/jdk with Shenandoah enabled. Seems to be problematic with Traversal:

$ CONF=linux-x86_64-server-fastdebug make run-test TEST=applications/ctw/modules/
TEST_VM_OPTS="-XX:+UnlockExperimentalVMOptions -XX:+UnlockDiagnosticVMOptions -XX:+UseShenandoahGC
-XX:-TieredCompilation -XX:+ShenandoahVerifyOptoBarriers -XX:ShenandoahGCHeuristics=traversal"

Sample hs_errs:
 http://cr.openjdk.java.net/~shade/shenandoah/crashes/ctw-traversal/

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  Internal Error (/home/shade/trunks/jdk-jdk/src/hotspot/cpu/x86/relocInfo_x86.cpp:56), pid=25735,
tid=25748
#  guarantee(*(uint32_t*) disp == CompressedOops::encode((oop)x)) failed: instructions must match

...
V  [libjvm.so+0x1559b99]  Relocation::pd_set_data_value(unsigned char*, long, bool)+0x369
V  [libjvm.so+0x9dcfb3]  CompiledMethod::verify_oop_relocations()+0x133
V  [libjvm.so+0x138f962]  nmethod::oops_do_marking_epilogue()+0x72
V  [libjvm.so+0x1694541]  ShenandoahTraversalGC::init_traversal_collection()+0x381
V  [libjvm.so+0x163e8c1]  ShenandoahHeap::entry_init_traversal()+0x101
V  [libjvm.so+0x16c618a]  VM_ShenandoahInitTraversalGC::doit()+0x2a
V  [libjvm.so+0x18d7b21]  VM_Operation::evaluate()+0x1f1
V  [libjvm.so+0x19080f0]  VMThread::evaluate_operation(VM_Operation*) [clone .constprop.64]+0x180
V  [libjvm.so+0x1908b4c]  VMThread::loop()+0x71c
V  [libjvm.so+0x190919a]  VMThread::run()+0xca
V  [libjvm.so+0x1813b66]  Thread::call_run()+0xf6
V  [libjvm.so+0x141c40e]  thread_native_entry(Thread*)+0x10e

-- 
Thanks,
-Aleksey