IV33473: INCORRECT EXECUTION OF CONDITIONAL ARITHMETIC OPERATION IN JIT C OMPILED CODE

APAR status

• Closed as program error.

Error description

• Error Message: A conditional int arithmetic operation is
  incorrectly executed, even if the condition evaluates to false.
  The condition guarding the arithmetic operation is a comparison
  of a long value with zero.
  .
  Stack Trace: N/A
  .
  

Local fix

• The issue can be worked around using
  -Xjit:disableAndSimplification, applied to the failing method.
  

Problem summary

• This problem is caused by a JIT optimization to convert the
  conditional code to an unconditional sequence using shifting and
  bitwise operations.  In the failing scenario, the long value in
  the condition is incorrectly truncated to an integer before
  shifting, leading to incorrect execution of the arithmetic
  operation.
  

Problem conclusion

• This defect will be fixed in:
  7.0.0 SR4
  6.0.1 SR5
  .
  The JIT compiler has been updated to avoid the incorrect
  truncation of the long value in this scenario.
  

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

• R260 PSY

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