IJ35230: JIT Compiler crash on z/OS or Linux on Z in OMR::CodeGenerator::decReferenceCount with vmState=0x0005ff04

APAR status

• Closed as program error.

Error description

• Error Message: Unhandled exception
  Unhandled exception
  Type=Segmentation error vmState=0x0005ff04
  J9Generic_Signal_Number=00000018 Signal_Number=0000000b
  Error_Value=00000000 Signal_Code=00000035
  ...
  ...
  Method_being_compiled=<Signature of Java package/class.method
  that crashed during JIT compilation>
  
  .
  Stack Trace:
  OMR::CodeGenerator::decReferenceCount(TR::Node*)+0xea452c50
  (0x0000000000000000)
  genericRotateAndInsertHelper(TR::Node*,TR::CodeGenerator*)+0xea4
  30358 (0x0000000000000000)
  OMR::Z::TreeEvaluator::iandEvaluator(TR::Node*,TR::CodeGenerator
  *)+0xea424528 (0x0000000000000000)
  OMR::CodeGenerator::evaluate(TR::Node*)+0xea4534c0
  (0x0000000000000000)
  OMR::Z::TreeEvaluator::iRegStoreEvaluator(TR::Node*,TR::CodeGene
  rator*)+0xea6a3f90 (0x0000000000000000)
  OMR::CodeGenerator::evaluate(TR::Node*)+0xea4534c0
  (0x0000000000000000)
  J9::CodeGenerator::doInstructionSelection()+0xeac345f8
  (0x0000000000000000)
  

Local fix

• The failing method being compiled can be excluded from JIT
  compilation using -Xjit:exclude={<package/class.method*>}
  

Problem summary

• The JIT Compiler on z/OS and Linux on Z may perform an
  optimization that causes a bit-wise-and operation to be folded
  by exploiting rotate-and-insert instruction. In the failing
  scenario, this optimization results in operands of the
  bit-wise-and operation to be incorrectly evaluated twice,
  resulting a crash when over decrementing the node's reference
  count.
  

Problem conclusion

• The problem is resolved by limiting the JIT Compiler to only
  perform this optimization when the bit-wise-and node's reference
  count is equal to 1, avoiding the problematic scenario.
  .
  This APAR will be fixed in the following Java Releases:
   8 SR7 FP5 (8.0.7.5)
  .
  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

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