4.5.2 /arclimit, /arclm, (/arclimit=5000)

The /arclimit qualifier sets the size of the dependence arc data structure that KAP uses to perform data dependence analysis

This data structure is dynamically allocated on a loop-nest-by- loop-nest basis. By default, this data structure is allocated with a size = max (# of statements * 4 , /arclimit value). If a loop contains too many dependence relationships and cannot be represented in the dependence data structure, KAP will give up optimization of the loop. Loops that exceeded this threshold will be marked in the Loop Table (/listoptions=l ) in the listing file.

You can use the /arclimit qualifier to increase the size of the data structure to enable KAP to perform more optimizations. Reducing the /arclimit value will (slightly) reduce the size of the KAP executable, while reducing the complexity of loops that KAP can analyze. (Most users will not need to change this value.)

The maximum value is 5000. If a larger value is specified, and the "KAP qualifiers" (/listoptions=k ) section is enabled, the entry for arclimit is /arclimit override=5000 . The value will be set to 5000.

The dependence arc data structure size can also be modified with the C*$* arclimit <integer> directive.

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Command-Line Qualifiers

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