IBM Support

IV84283: JAVA JIT 7.1 - INCORRECT CASE IS USED FOR A SWITCH

Subscribe to this APAR

By subscribing, you receive periodic emails alerting you to the status of the APAR, along with a link to the fix after it becomes available. You can track this item individually or track all items by product.

Notify me when this APAR changes.

Notify me when an APAR for this component changes.

 

APAR status

  • Closed as program error.

Error description

  • Error Message: The problem can surface in many different ways,
    the original report was a SEGSEGV, but an unexpected NPE or
    other incorrect behavior can result.
    .
    Stack Trace: N/A
    .
    The problem can only occur in Java 7.1 (Java 7 using the J9 27
    VM). Java 6, Java 7.0 and Java 8 are not effected by this issue.
    

Local fix

  • The problem can be avoided by using the following java command
    line option:
    -Xjit:disableTreeSimplification
    The use of this option will have a small effect on performance.
    

Problem summary

  • The JIT would try to simplify a switch statement in cases where
    the switch variable is manipulated with a shift instruction. In
    such cases the JIT would neglect to update a reference counter
    which would allow later JIT optimizations to remove code that is
    still required by the switch statement.
    

Problem conclusion

  • The JIT was modified to correctly update the reference counter.
    .
    This APAR will be fixed in the following Java Releases:
       7 R1 SR3 FP50  (7.1.3.50)
    .
    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

    IV84283

  • Reported component name

    JIT

  • Reported component ID

    620700124

  • Reported release

    130

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2016-04-29

  • Closed date

    2016-05-05

  • Last modified date

    2016-05-05

  • 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

       UP

[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSC9HBA","label":"Just In Time (JIT) Compiler"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"130","Edition":"","Line of Business":{"code":"","label":""}}]

Document Information

Modified date:
05 May 2016