IJ11116: ILLEGAL LOCR INSTRUCTION ON Z10

APAR status

• Closed as program error.

Error description

• Error Message: The JRE reports the following error message
  Type=Illegal instruction vmState=0x00000000
  .
  Stack Trace: N/A
  .
  This problem can only happen on IBM Z on z10 machines
  

Local fix

• This problem can be avoided using the following command line
  option:
  -Xjit:disableMaxMinOptimization
  

Problem summary

• The JIT compiler has an optimized version of the max/min
  operation which uses the LOCR instruction which is not available
  on z10. A guard was missing for this operation so it was
  possible for the JIT compiler to generate on LOCR on z10 which
  results in an illegal instruction exception when executed.
  

Problem conclusion

• The following commit fixes this problem.
  https://github.com/eclipse/omr/commit/04c6437444222d4ad94c5d3e00
  da6c29e17dd389
  .
  This APAR will be fixed in the following Java Releases:
   8 SR5 FP25 (8.0.5.25)
  .
  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:

• Fixed component name

  JIT

• Fixed component ID

  620700124

Applicable component levels