IJ57022: CRASH DURING JIT COMPILATION WHEN FSD (DEBUG) ENABLED

APAR status

• Closed as program error.

Error description

• Error Message: The JVM crashes unexpectedly while the JIT is
  compiling a method and the JVM is running in debug mode (FSD
  enabled is shown on the jitmodes line in the javacore).
  .
  Stack Trace: In the only report of the problem so far, the call
  stack was
  TR_OSRDefInfo::addSharingInfo+0x39f (OSRDefAnalysis.cpp:209,
  0x00007FFD24B1A16F <OSB>j9jit29+0x5ea16f<CSB>)
  TR_OSRDefInfo::performAnalysis+0x45 (OSRDefAnalysis.cpp:92,
  0x00007FFD24B190F5 <OSB>j9jit29+0x5e90f5<CSB>)
  TR_UseDefInfo::prepareUseDefInfo+0x135a (UseDefInfo.cpp:358,
  0x00007FFD24B7794A <OSB>j9jit29+0x64794a<CSB>)
  TR_OSRDefAnalysis::perform+0x50c (OSRDefAnalysis.cpp:638,
  0x00007FFD24B1B1FC <OSB>j9jit29+0x5eb1fc<CSB>)
  OMR::Optimizer::performOptimization+0x171d
  (OMROptimizer.cpp:2063, 0x00007FFD24A96BED
  <OSB>j9jit29+0x566bed<CSB>)
  OMR::Optimizer::optimize+0x3c5 (OMROptimizer.cpp:1122,
  0x00007FFD24A93575 <OSB>j9jit29+0x563575<CSB>)
  OMR::ResolvedMethodSymbol::genIL+0x757
  (OMRResolvedMethodSymbol.cpp:1273, 0x00007FFD2492C967
  <OSB>j9jit29+0x3fc967<CSB>)
  OMR::Compilation::compile+0x31e (OMRCompilation.cpp:1009,
  0x00007FFD248D1CAE <OSB>j9jit29+0x3a1cae<CSB>)
  .
  

Local fix

• The problem only happens in debug mode, so first confirm that
  running with debug is intentional.
  The method that triggered the problem in the JIT compiler can be
  excluded using the -Xjit:exclude= option, e.g. if the compiler
  failed while compiling a.b.AClass.aMethod it can be excluded
  from compilation with
  -Xjit:exclude={a/b/AClass.aMethod(*}
  If an existing Xjit option is already being used it can either
  be merged with the new exclude parameter or multiple JIT options
  can be automatically merged by specifying
  -XX:+MergeCompilerOptions
  

Problem summary

• While JIT compiling in debug mode, an edge case could occur
  where constant branch folding allowed a section of code to be
  removed prior to running OSR analysis that assumes the IL still
  represents the complete bytecodes of the method.
  

Problem conclusion

• The JIT has been updated to not perform the early phase of
  branch folding during ilgen when OSR is enabled (which can
  happen when running in debug mode).
  https://github.com/eclipse-openj9/openj9/pull/23097
  .
  This APAR will be fixed in the following Releases:
  .
  IBM Semeru Runtimes
     25              25.0.3.0
     21              21.0.11.0
     17              17.0.19.0
     11              11.0.31.0
  IBM SDK, Java Technology Edition
     8    SR8 FP65  (8.0.8.65)
  .
  Downloads and supplementary documentation can be found at the
  following locations:
  - For non z/OS operating systems:
    - IBM Semeru Runtimes, Version 11 and later
      https://www.ibm.com/semeru-runtimes/downloads/
    - IBM SDK, Java Technology Edition, Version 8
      https://www.ibm.com/support/pages/java-sdk-downloads/
  - For the z/OS operating system:
    - Java SDK Products on z/OS
      https://www.ibm.com/support/pages/java-sdk-products-zos
  

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