IJ27633: SEGMENTATION FAULT IN JIT MODULE ON IBM Z PLATFORM

APAR status

• Closed as program error.

Error description

• Error Message: "Assertion failed at
  */omr/compiler/il/OMRBlock.cpp:923: false"
  .
  Stack Trace:
  TR_MvsCallStackIterator::TR_MvsCallStackIterator()+0xffffffff840
  02940
  TR_Debug::printStackBacktrace()+0x20
  TR::fatal_assertion(const char*,int,const char*,const
  char*,...)+0x24c
  findAvailableRegister(TR::Compilation*,TR::Node*,TR_BitVector&)+
  0x198
  OMR::Block::splitPostGRA(TR::TreeTop*,TR::CFG*,bool,TR::Resolved
  MethodSymbol*)+0x1a1a
  TR_JProfilingValue::addProfilingTrees(TR::Compilation*,TR::TreeT
  op*,TR::Node*,TR_AbstractHa...+0x29a
  TR_JProfilingValue::lowerCalls()+0x95c
  TR_JProfilingValue::perform()+0x13a
  OMR::Optimizer::performOptimization(const
  OptimizationStrategy*,int,int,int)+0x2610
  OMR::Optimizer::optimize()+0x642
  OMR::Compilation::compile()+0xbfc
  TR::CompilationInfoPerThreadBase::compile(J9VMThread*,TR::Compil
  ation*,TR_ResolvedMethod*,T...+0xa6e
  TR::CompilationInfoPerThreadBase::wrappedCompile(J9PortLibrary*,
  void*)+0x1fb2
  omrsig_protect+0x458
  TR::CompilationInfoPerThreadBase::compile(J9VMThread*,TR_MethodT
  oBeCompiled*,J9::J9SegmentP...+0x5ee
  TR::CompilationInfoPerThread::processEntry(TR_MethodToBeCompiled
  &,J9::J9SegmentProvider&)+0x666
  TR::CompilationInfoPerThread::processEntries()+0x63a
  protectedCompilationThreadProc(J9PortLibrary*,TR::CompilationInf
  oPerThread*)+0x664
  omrsig_protect+0x458
  compilationThreadProc(void*)+0x692
  thread_wrapper+0x9ba
  .
  "This issue is only possible in release starting with 8.0.6.5
  and can only occur on IBM Z (zOS/Linux on Z and LinuxONE) in
  applications that works with Packed Decimal data types either
  directly Data Access Accelerator library or indirectly via JZOS
  or similar libraries and cannot occur on POWER or x86 systems."
  

Local fix

• "Using JIT option -Xjit:disableJProfilingInProfilingCompilations
  will disable the part of the code that causes the issue. On
  average this option might have performance impact of around 1-3%
  depending on the workload."
  

Problem summary

• For handful of highly frequently executed methods in the
  workload, JIT compiler will compile them with inlined profiling
  code to collect more information in order to collect data that
  drives the optimization to generate high quality and efficient
  code. When adding a profiling code, it encountered a data type
  for which it had no support and it threw JIT assert.
  

Problem conclusion

• Compiler code has been updated to add the support of the data
  type due to which it was failing.
  .
  This APAR will be fixed in the following Java Releases:
     8    SR6 FP16  (8.0.6.16)
  .
  Contact your IBM Product's Service Team for these Service
  Refreshes and Fix Packs.
  For those running stand-alone, information about the available
  Service Refreshes and Fix Packs can be found at:
             https://www.ibm.com/developerworks/java/jdk/
  

Temporary fix

• N/A
  

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  JIT

• Fixed component ID

  620700124

Applicable component levels