IJ01928: ON Z14, CHECKPACKEDDECIMAL() DAA API RETURNS UNEXPECTED INTEGER RESULTS

APAR status

• Closed as program error.

Error description

• Error Message: N/A
  .
  Stack Trace: N/A
  .
  An input packed decimal with an even number of digits is passed
  as an argument to the checkPackedDecimal() method call. The
  nibble proceeding its top (most significant digit) nibble was an
  invalid digit. Also, the overwrite boolean argument to this
  method call was set as true. The expected return value was 0
  (indicating a valid packed decimal), but the function returned 2
  for invalid digits. This problem is on z14 only.
  

Local fix

• N/A
  

Problem summary

• The problem is caused by the JIT evaluator not emitting correct
  z14 instructions to validate and modify even-precision packed
  decimal inputs. If a packed decimal input has an even number of
  digits, there will be an extra nibble loaded from memory for
  processing. This extra top nibble is not part of the input and
  could contain corrupted non-zero data. This top nibble should be
  cleared before performing the testPackedDecimal() step. But the
  instructions produced by the JIT failed to zero-out the invalid
  top nibble and returns 2 for invalid inputs.
  

Problem conclusion

• A JIT bug fix has been delivered to emit correct z/Architecture
  instructions to fix the problem by zeroing out extra top nibble
  if the input to testPackedDecimal() is an even-precision packed
  decimal.
  .
  This APAR will be fixed in the following Java Releases:
     8    SR5 FP5   (8.0.5.5)
  .
  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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