Visible to Intel only — GUID: GUID-05900346-FEFC-4CC7-A93B-6D3769367FA5
Visible to Intel only — GUID: GUID-05900346-FEFC-4CC7-A93B-6D3769367FA5
OpenMP* Fortran Compiler Directives
Intel® Fortran supports OpenMP* Fortran compiler directives that comply with OpenMP Fortran Application Program Interface (API) specification 5.0 Version TR4, and some of the directives of the OpenMP Version 5.1 specification.
To use these directives, you must specify compiler option -qopenmp (Linux* and macOS) or /Qopenmp (Windows*).
OpenMP directives are specially formatted Fortran comment lines embedded in the source file which provide the compiler with hints and suggestions for parallelization, optimization, vectorization, and offloading code to accelerator hardware. The compiler uses the information specified in the directives with compiler heuristic algorithms to generate more efficient code. At times, these heuristics may choose to ignore or override the information provided by a directive. If the directive is ignored by the compiler, no diagnostic message is issued.
Options that use OpenMP are available for both Intel® microprocessors and non-Intel microprocessors, but these options may perform additional optimizations on Intel® microprocessors than they perform on non-Intel microprocessors. The list of major, user-visible OpenMP constructs and features that may perform differently on Intel® microprocessors vs. non-Intel microprocessors includes: locks (internal and user visible), the SINGLE construct, barriers (explicit and implicit), parallel loop scheduling, reductions, memory allocation, thread affinity, and binding.
The following OpenMP Fortran directives are available:
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Specifies memory allocators to use for object allocation and deallocation. This feature is only available for ifx.
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Specifies memory allocators to use for object allocation in Fortran ALLOCATE statements and for their deallocation. This feature is only available for ifx.
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Provides hints to the optimizer about the current compilation unit and all the code it can reach through procedure calls. This feature is only available for ifx.
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Specifies that a specific memory location is to be updated atomically.
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Synchronizes all the threads in a team.
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Requests cancellation of the innermost enclosing region of the type specified, and causes the encountering implicit or explicit task to proceed to the end of the canceled construct.
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Defines a point at which implicit or explicit tasks check to see if cancellation has been requested for the innermost enclosing region of the type specified.
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Restricts access for a block of code to only one thread at a time.
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Declares a user-defined data mapper for derived types and local variables that can subsequently be used in MAP clauses. This feature is only available for ifx.
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Declares a user-defined reduction for one or more types.
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Declares a user-defined reduction for one or more types.
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Generates a SIMD procedure.
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Causes the creation of a device-specific version of a named routine that can be called from a target region. This feature is only available for ifx.
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Initializes, updates, or uninitializes an OpenMP depend object. This feature is only available for ifx.
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Identifies a variant of a base procedure and specifies the context in which this variant is used. This feature is only available for ifx.
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Determines if a variant of a base procedure is to be called for a given subroutine or function call. This feature is only available for ifx.
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Specifies that loop iterations will be executed by thread teams in the context of their implicit tasks.
DISTRIBUTE PARALLEL DO construct
Specifies a loop that can be executed in parallel by multiple threads that are members of multiple teams.
DISTRIBUTE PARALLEL DO SIMD construct
Specifies a loop that will be executed in parallel by multiple threads that are members of multiple teams. It will be executed concurrently using SIMD instructions.
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Specifies a loop that will be distributed across the primary threads of the teams region. It will be executed concurrently using SIMD instructions.
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Specifies that the iterations of the immediately following DO loop must be executed in parallel.
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Specifies a loop that can be executed concurrently using SIMD instructions.
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Causes the compiler or runtime system to process an error condition. This feature is only available for ifx.
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Specifies synchronization points where the threads in a team must have a consistent view of memory.
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Identifies a foreign runtime context and identifies runtime characteristics of that context, enabling interoperability with it. This feature is only available for ifx.
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Specifies that the iterations of the associated loops can execute concurrently. This feature is only available for ifx.
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Specifies a block of code to be executed by a subset of threads of the current team. This feature is only available for ifx.
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Provides an abbreviated way to specify a TASKLOOP construct inside a MASKED construct. This feature is only available for ifx.
MASKED TASKLOOP SIMD construct
Provides an abbreviated way to specify a TASKLOOP SIMD construct inside a MASKED construct. This feature is only available for ifx.
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Deprecated; see MASKED. Specifies a block of code to be executed by the master thread of the team.
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Deprecated; provides an abbreviated way to specify a TASKLOOP construct inside a MASTER construct. This feature is only available for ifx.
MASTER TASKLOOP SIMD construct
Deprecated; provides an abbreviated way to specify a TASKLOOP SIMDconstruct inside a MASTER construct. This feature is only available for ifx.
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Provides documentary clarity in conditionally compiled code or conditional OpenMP* code. It has no effect on the semantics or execution of the program. This feature is only available for ifx.
ORDERED directive and construct
Specifies a block of code that the threads in a team must execute in the natural order of the loop iterations.
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Defines a parallel region.
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Defines a parallel region that contains a single DO directive.
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Specifies a loop that can be executed concurrently using SIMD instructions. It provides a shortcut for specifying a PARALLEL construct containing one SIMD loop construct and no other statement.
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Specifies a shortcut for indicating that a loop or loop nest can execute concurrently across multiple threads. This feature is only available for ifx.
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Provides an abbreviated way to specify a MASKED construct inside a PARALLEL construct.This feature is only available for ifx.
PARALLEL MASKED TASKLOOP construct
Provides an abbreviated way to specify a MASKED TASKLOOP construct inside a PARALLEL construct.This feature is only available for ifx.
PARALLEL MASKED TASKLOOP SIMD construct
Provides an abbreviated way to specify a MASKED TASKLOOP SIMD construct inside a PARALLEL construct.This feature is only available for ifx.
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Deprecated; provides an abbreviated way to specify a MASTER construct inside a PARALLEL construct. This feature is only available for ifx.
PARALLEL MASTER TASKLOOP construct
Deprecated; provides an abbreviated way to specify a MASTER TASKLOOP construct inside a PARALLEL construct. This feature is only available for ifx.
PARALLEL MASTER TASKLOOP SIMD construct
Deprecated; provides an abbreviated way to specify a MASTER TASKLOOP SIMD construct inside a PARALLEL construct. This feature is only available for ifx.
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Defines a parallel region that contains a single SECTIONS directive.
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Defines a parallel region that contains a single WORKSHARE directive.
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Suggests to the compiler to preload data into cache. Preloading data in cache minimizes the effects of memory latency. This feature is only available for ifx.
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Lists the features that an implementation must support so that the program compiles and runs correctly. This feature is only available for ifx.
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Specifies a scan computation that updates each list item in each iteration of the loop the directive appears in.
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Specifies a block of code to be executed by all threads in a team. This feature is only available for ifx.
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Specifies that the enclosed SECTION directives define blocks of code to be divided among threads in a team.
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Requires and controls SIMD vectorization of loops.
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Specifies a block of code to be executed by only one thread in a team at a time.
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Creates a device data environment and executes the construct on the same device. This feature is only available for ifx.
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Creates a device data environment for the extent of the region. This feature is only available for ifx.
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Specifies that variables are mapped to a device data environment. This feature is only available for ifx.
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Specifies that variables are unmapped from a device data environment. This feature is only available for ifx.
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Creates a device data environment in a parallel region and executes the construct on that device.
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Provides an abbreviated way to specify a TARGET directive containing a PARALLEL DO directive and no other statements.
TARGET PARALLEL DO SIMD construct
Specifies a TARGET construct that contains a PARALLEL DO SIMD construct and no other statement.
TARGET PARALLEL LOOP construct
Specifies a shortcut for specifying a parallel loop inside a TARGET construct that contains no other statements than the parallel loop. This feature is only available for ifx.
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Specifies a TARGET construct that contains a SIMD construct and no other statement.
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Creates a device data environment and executes the construct on the same device. It also creates a league of thread teams with the primary thread in each team executing the structured block.
TARGET TEAMS DISTRIBUTE construct
Creates a device data environment and executes the construct on the same device. It also specifies that loop iterations will be shared among the primary threads of all thread teams in a league created by a TEAMS construct.
TARGET TEAMS DISTRIBUTE PARALLEL DO construct
Creates a device data environment and then executes the construct on that device. It also specifies a loop that can be executed in parallel by multiple threads that are members of multiple teams created by a TEAMS construct.
TARGET TEAMS DISTRIBUTE PARALLEL DO SIMD construct
Creates a device data environment and then executes the construct on that device. It also specifies a loop that can be executed in parallel by multiple threads that are members of multiple teams created by a TEAMS construct. The loop will be distributed across the teams, which will be executed concurrently using SIMD instructions.
TARGET TEAMS DISTRIBUTE SIMD construct
Creates a device data environment and executes the construct on the same device. It also specifies that loop iterations will be shared among the master threads of all thread teams in a league created by a teams construct. It will be executed concurrently using SIMD instructions.
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Specifies a shortcut for specifying a TEAMS LOOP construct inside a TEAMS construct that contains no other statements. This feature is only available for ifx.
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Makes the list items in the device data environment consistent with their corresponding original list items. This feature is only available for ifx.
TARGET VARIANT DISPATCH directive
Conditionally calls a procedure offload variant if the device is free; otherwise, executes the procedure on the host. This feature is only available for ifx.
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Defines a task region.
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Specifies a wait for the completion of all child tasks of the current task and all of their descendant tasks.
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Specifies that the iterations of one or more associated DO loops should be executed in parallel using OpenMP* tasks. The iterations are distributed across tasks that are created by the construct and scheduled to be executed.
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Specifies a loop that can be executed concurrently using SIMD instructions and that those iterations will also be executed in parallel using OpenMP* tasks.
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Specifies a wait on the completion of child tasks generated since the beginning of the current task.
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Specifies that the current task can be suspended at this point in favor of execution of a different task.
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Creates a group of thread teams to be used in a parallel region. This feature is only available for ifx.
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Creates a league of thread teams to execute a structured block in the primary thread of each team. It also specifies that loop iterations will be shared among the primary threads of all thread teams in a league created by a TEAMS construct.
TEAMS DISTRIBUTE PARALLEL DO construct
Creates a league of thread teams to execute a structured block in the primary thread of each team. It also specifies a loop that can be executed in parallel by multiple threads that are members of multiple teams.
TEAMS DISTRIBUTE PARALLEL DO SIMD construct
Creates a league of thread teams to execute a structured block in the primary thread of each team. It also specifies a loop that can be executed in parallel by multiple threads that are members of multiple teams. The loop will be distributed across the primary threads of the teams region, which will be executed concurrently using SIMD instructions.
TEAMS DISTRIBUTE SIMD construct
Creates a league of thread teams to execute the structured block in the primary thread of each team. It also specifies a loop that will be distributed across the primary threads of the teams region. The loop will be executed concurrently using SIMD instructions.
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Specifies a shortcut for specifying a LOOP construct inside a TEAMS construct. This feature is only available for ifx.
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Makes named common blocks private to each thread, but global within the thread.
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Tiles (or blocks) one or more loops in a loop nest. This feature is only available for ifx.
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Partially or fully unrolls a DO loop. This feature is only available for ifx.
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Divides the work of executing a block of statements or constructs into separate units.
The OpenMP parallel directives can be grouped into the categories. For more information about the categories for these directives, see OpenMP* Directives Summary.
Product and Performance Information |
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Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex. Notice revision #20201201 |