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 number
IJ35230
Reported component name
JIT
Reported component ID
620700124
Reported release
130
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2021-09-28
Closed date
2021-09-29
Last modified date
2021-11-30
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
[{"Line of Business":{"code":"LOB36","label":"IBM Automation"},"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSNVBF","label":"Runtimes for Java Technology"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"130"}]
Document Information
Modified date:
30 November 2021