OMPSchedule¶
schedule: how loop iterations are divided among the threads.
Declaration¶
Syntax¶
OMPSchedule(schedule_type kind, expr? chunk_size)
Arguments¶
Argument |
Description |
|---|---|
|
which schedule; see schedule_type. |
|
how many iterations to hand out at a time, or |
Return values¶
None.
Description¶
Static divides the iterations up front, which is cheapest when they cost the
same. Dynamic and Guided hand out chunks as threads become free, which
costs more but tolerates uneven work. Auto leaves the choice to the
implementation and Runtime to an environment variable.
Examples¶
(OMPSchedule
:kind :Static
:chunk_size (IntegerConstant
:n 1
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
It comes from this complete ASR text document:
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(OMPRegion
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(OMPPrivate
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(Var
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)
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(OMPShared
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(Var
:v (SymbolRef 1 "a")
)
]
)
(OMPFirstPrivate
:vars [
(Var
:v (SymbolRef 1 "n")
)
]
)
(OMPNumThreads
:num_threads (IntegerConstant
:n 4
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
(OMPIf
:condition (Var
:v (SymbolRef 1 "run")
)
)
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(OMPSchedule
:kind :Static
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:n 1
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
(OMPCollapse
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:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
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:operator :ReduceAdd
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(Var
:v (SymbolRef 1 "total")
)
]
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(OMPLastPrivate
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:intboz_type :Decimal
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)
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:body [
(OMPRegion
:region :Teams
:clauses [
(OMPNumTeams
:num_teams (IntegerConstant
:n 2
:type (Integer
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)
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(OMPThreadLimit
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)
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)