PH45898: The IGZXDIVZ sample does not return expected values for infinity with an IEEE-Division-By-Zero operation

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• In environments where vector registers are active, for example
  Java 8, the infinity placed in the floating point area of the
  resume state is being replaced by values in the vector register
  area of the resume state.
  
  (The floating point registers are colocated with the upper
  halves of vector registers 0-15 in the hardware, but not in the
  resume state.)
  

Local fix

• Use a prior Java version, such as Java 7.1.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: Users of Enterprise COBOL 5 and later        *
  *                 releases running programs that use           *
  *                 IGZXDIVZ handler sample.                     *
  ****************************************************************
  * PROBLEM DESCRIPTION: The IGZXDIVZ handler sample may         *
  *                      incorrectly result in an unexpected     *
  *                      value instead of "infinity" with an     *
  *                      IEEE divide by zero operation.          *
  ****************************************************************
  * RECOMMENDATION: Install the provided PTF.                    *
  ****************************************************************
  The IGZXDIVZ handler sample failed to account for the
  possibility that the vector registers might be active. In that
  case, the "infinity" placed by the handler in the target
  floating point register of the instruction receiving the
  division-by-zero was being overwritten by the corresponding
  vector register value, as the vector registers are restored
  last during the resume processing if active.
  
  COB0501T/K COB0502T/K COB0601T/K COB0602T/K COB0603T/K
  COB0604T/K
  

Problem conclusion

• Sample IGZXDIVZ has been updated to correctly handle when
  an IEEE divide by zero operation occurs and vector registers
  are active. The IGZXDIVZ places a correct "infinity" value.
  
  Follow the instructions in the IGZXDIVZ sample installed by this
  PTF to compile and link the condition handler into the SCEERUN
  dataset, and use the LE runtime option USRHDLR with
  the affected application.
  

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:

Modules/Macros

• IGZCEV4  IGZCJNI2 IGZLLIBV IGZXAPI  IGZXCA31 IGZXCDA  IGZXD24
  IGZXDIVZ IGZXDMR  IGZXJNI2 IGZXLPIO IGZXLPKA IGZXLPKB IGZXLPKC
  IGZXLPKD IGZXLPKE IGZXLPKF IGZXLPKG IGZXPK2
  

Fix information

• Fixed component name

  LE ENT COBOL LI

• Fixed component ID

  568819812

Applicable component levels

• R7C0 PSY UI91392

     UP23/04/26 P F304

• R7D0 PSY UI91393

     UP23/04/26 P F304

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.