OMPPrivate¶
private: each thread gets its own uninitialised copy.
Declaration¶
Syntax¶
OMPPrivate(expr* vars)
Arguments¶
Argument |
Description |
|---|---|
|
the variables the clause applies to. |
Return values¶
None.
Description¶
The copies start undefined, and the original variable is unchanged when the region ends. OMPFirstPrivate is the variant that copies the value in, and OMPLastPrivate the one that copies it back out.
Examples¶
(OMPPrivate
:vars [
(Var
:v (SymbolRef 1 "i")
)
]
)
It comes from this complete ASR text document:
(TranslationUnit
:symtab (SymbolTable
:id 0
:symbols {
"main" (Program
:symtab (SymbolTable
:id 1
:symbols {
"a" (Variable
:parent_symtab 1
:name "a"
:dependencies []
:intent :Local
:symbolic_value nil
:value nil
:storage :Default
:type (Array
:type (Integer
:kind 4
)
:dims [
(dimension
:start (IntegerConstant
:n 1
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
:length (IntegerConstant
:n 3
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
]
:physical_type :FixedSizeArray
)
:type_declaration nil
:abi :Source
:access :Public
:presence :Required
:value_attr false
:target_attr false
:contiguous_attr false
:bindc_name nil
:is_volatile false
:is_protected false
:pass_attr :NotMethod
:self_argument nil
:codims []
)
"i" (Variable
:parent_symtab 1
:name "i"
:dependencies []
:intent :Local
:symbolic_value nil
:value nil
:storage :Default
:type (Integer
:kind 4
)
:type_declaration nil
:abi :Source
:access :Public
:presence :Required
:value_attr false
:target_attr false
:contiguous_attr false
:bindc_name nil
:is_volatile false
:is_protected false
:pass_attr :NotMethod
:self_argument nil
:codims []
)
"n" (Variable
:parent_symtab 1
:name "n"
:dependencies []
:intent :Local
:symbolic_value nil
:value nil
:storage :Default
:type (Integer
:kind 4
)
:type_declaration nil
:abi :Source
:access :Public
:presence :Required
:value_attr false
:target_attr false
:contiguous_attr false
:bindc_name nil
:is_volatile false
:is_protected false
:pass_attr :NotMethod
:self_argument nil
:codims []
)
"run" (Variable
:parent_symtab 1
:name "run"
:dependencies []
:intent :Local
:symbolic_value nil
:value nil
:storage :Default
:type (Logical
:kind 4
)
:type_declaration nil
:abi :Source
:access :Public
:presence :Required
:value_attr false
:target_attr false
:contiguous_attr false
:bindc_name nil
:is_volatile false
:is_protected false
:pass_attr :NotMethod
:self_argument nil
:codims []
)
"total" (Variable
:parent_symtab 1
:name "total"
:dependencies []
:intent :Local
:symbolic_value nil
:value nil
:storage :Default
:type (Integer
:kind 4
)
:type_declaration nil
:abi :Source
:access :Public
:presence :Required
:value_attr false
:target_attr false
:contiguous_attr false
:bindc_name nil
:is_volatile false
:is_protected false
:pass_attr :NotMethod
:self_argument nil
:codims []
)
}
)
:name "main"
:dependencies []
:body [
(OMPRegion
:region :Parallel
:clauses [
(OMPPrivate
:vars [
(Var
:v (SymbolRef 1 "i")
)
]
)
(OMPShared
:vars [
(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")
)
)
]
:body [
(OMPRegion
:region :Do
:clauses [
(OMPSchedule
:kind :Static
:chunk_size (IntegerConstant
:n 1
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
(OMPCollapse
:count (IntegerConstant
:n 1
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
(OMPReduction
:operator :ReduceAdd
:vars [
(Var
:v (SymbolRef 1 "total")
)
]
)
(OMPLastPrivate
:vars [
(Var
:v (SymbolRef 1 "i")
)
]
)
(OMPNowait)
]
:body [
(DoLoop
:name nil
:head (do_loop_head
:v (Var
:v (SymbolRef 1 "i")
)
:start (IntegerConstant
:n 1
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
:end (IntegerConstant
:n 3
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
:increment (IntegerConstant
:n 1
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
:body [
(Assignment
:target (Var
:v (SymbolRef 1 "total")
)
:value (IntegerBinOp
:left (Var
:v (SymbolRef 1 "total")
)
:op :Add
:right (Var
:v (SymbolRef 1 "i")
)
:type (Integer
:kind 4
)
:value nil
)
:overloaded nil
:realloc_lhs false
:move_allocation false
)
]
:orelse []
)
]
)
]
)
(OMPRegion
:region :Target
:clauses [
(OMPMap
:type :ToFrom
:vars [
(Var
:v (SymbolRef 1 "a")
)
]
)
(OMPDevice
:device (IntegerConstant
:n 0
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
]
:body [
(OMPRegion
:region :Teams
:clauses [
(OMPNumTeams
:num_teams (IntegerConstant
:n 2
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
(OMPThreadLimit
:thread_limit (IntegerConstant
:n 64
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
)
]
:body [
(Assignment
:target (Var
:v (SymbolRef 1 "total")
)
:value (IntegerConstant
:n 0
:type (Integer
:kind 4
)
:intboz_type :Decimal
)
:overloaded nil
:realloc_lhs false
:move_allocation false
)
]
)
]
)
]
)
}
)
:items []
)
See Also¶
OMPShared, OMPFirstPrivate, OMPLastPrivate, OMPRegion, omp_clause