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IV57389: COMPILER USES XVCPSGND INSTEAD OF XXLOR

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You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • For certain specific sequences of source code, the xlc compiler
    generates xvcpsgnd instructions instead of the xxlor instruction
    causing programs to be not as fast as they cab be.
    

Local fix

  • N/A
    

Problem summary

  • USERS AFFECTED:
    Those using -qarch/tune=pwr7 and higher; along with -O2 and
    higher maybe affected by this issue.
    
    PROBLEM DESCRIPTION:
    Less performance for register moves with -qarch/tune=pwr7 and
    up may be experienced.
    

Problem conclusion

  • The compiler has been fixed to improve the instruction
    selection for vector register moves to improve performance.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IV57389

  • Reported component name

    XL C/C++ FOR AI

  • Reported component ID

    5725C7200

  • Reported release

    C10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2014-03-25

  • Closed date

    2014-10-23

  • Last modified date

    2014-10-23

  • APAR is sysrouted FROM one or more of the following:

  • APAR is sysrouted TO one or more of the following:

    IV67986 LI78428

Fix information

  • Fixed component name

    XL C FOR AIX

  • Fixed component ID

    5725C7100

Applicable component levels



Document information

More support for: XL C for AIX
Compiler

Software version: 12.1

Reference #: IV57389

Modified date: 23 October 2014