IV99783: CRASHES IN JIT-COMPILED JAVA CODE ON POWER PLATFORMS

APAR status

• Closed as program error.

Error description

• Error Message: User observed incorrect results and occasional
  crashes on POWER platforms.
  .
  Stack Trace: N/A
  .
  This problem only affects POWER systems.
  

Local fix

• This problem can be worked around by defining the
  TR_DisableLHSPeephole variable in your environment and setting
  it to any value. Note that this may have a minor performance
  impact.
  Note that this environment variable is unsupported and may be
  removed in future.
  

Problem summary

• The JIT compiler incorrectly optimizes away certain instructions
  that are deemed not necessary. In certain cases these
  instructions are in fact necessary in order to preserve the
  signed two's complement representations of values in registers.
  

Problem conclusion

• The JIT compiler has been modified to correctly recognize when
  these certain instructions are necessary to preserve integer
  representations and optimize them accordingly.
  .
  This APAR will be fixed in the following Java Releases:
     8    SR5       (8.0.5.0)
  .
  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

• R130 PSY

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