Fixes are available
APAR status
Closed as program error.
Error description
This is a performance degradation caused by a limitation in load/store motion in optimizer. Optimizer is no longer marking the multiplication by a literal value as invariant, which leaves additional computation inside of a hot loop.
Local fix
-qstrict=association might fix the problem, although it shouldn't to be considered as a general solution to the problem.
Problem summary
This is a performance degradation caused by a limitation in load/store motion in optimizer. Optimizer is no longer marking the multiplication by a literal value as invariant, which leaves additional computation inside of a hot loop.
Problem conclusion
Extended the existing load/store motion optimization to handle literal values. The net effect of this is that we can now consistently detect constant values as invariant code and move them outside of loops (if it is profitable to do so).
Temporary fix
Comments
APAR Information
APAR number
LI76303
Reported component name
XL FORTRAN LINU
Reported component ID
5724X1600
Reported release
D10
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2011-07-13
Closed date
2011-07-13
Last modified date
2011-07-13
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
XL FORTRAN LINU
Fixed component ID
5724X1600
Applicable component levels
RD10 PSY
UP
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Document Information
Modified date:
16 October 2021