OmpPragma

A helper class to rewrite some "pragma omp" (mostly teams and similar combined constructs), which are not supported by sotoc. More...

#include <OmpPragma.h>

Public Functions

	Name
	OmpPragma(TargetCodeRegion * TCR)
	OmpPragma(clang::OMPExecutableDirective * Directive, clang::PrintingPolicy PP)
bool	needsStructuredBlock() Returns true if the omp pragma encapsulated, needs to be followed by a structured block (i.e.
void	printReplacement(llvm::raw_ostream & Out) Prints a replacement omp pragma for the encapsulated pragma onto `Out`.
void	printAddition(llvm::raw_ostream & Out)
bool	isReplaceable(clang::OMPExecutableDirective * Directive) Determines whether a pragma is replacable.
bool	needsAdditionalPragma(clang::OMPExecutableDirective * Directive) Determines whether a additional pragma is needed.

Private Functions

	Name
bool	isClausePrintable(clang::OMPClause * Clause) Determine whether a clause is printable.
void	rewriteParam(std::string * In) Rewrite clause parameters.
void	printClauses(llvm::raw_ostream & Out) Print OMP Clauses.

Private Attributes

	Name
clang::PrintingPolicy	PP
llvm::ArrayRef< clang::OMPClause * >	Clauses
clang::OpenMPDirectiveKind	Kind
unsigned int	ClauseParamCounter

Detailed Description

1	`class OmpPragma;`

A helper class to rewrite some "pragma omp" (mostly teams and similar combined constructs), which are not supported by sotoc.

We currently only support one team to be run on the target because ncc does not support 'freestanding' teams. So we need to remove teams and distribute constructs from the generated target code. But teams constructs can also appear in combined constructs. These combined constructs cannot simply be removed, they must be replace by "non-team" equivalents to preserve correctness. This class provides helper functions that finds a suitable replacement for omp pragmas that contain teams constructs. It is used during code generation: The omp pragma of each target region that is declared as part of a combined construct and each pragma found during pretty printing is encapsulated by an object of this class which is then used to generate a replacement.

Public Functions Documentation

function OmpPragma

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inline OmpPragma(
    TargetCodeRegion * TCR
)

function OmpPragma

inline OmpPragma(
    clang::OMPExecutableDirective * Directive,
    clang::PrintingPolicy PP
)

function needsStructuredBlock

1	`bool needsStructuredBlock()`

Returns true if the omp pragma encapsulated, needs to be followed by a structured block (i.e.

Return: true If a structured block is needed

false If no structured block is needed

Determines whether a structured block is needed for a pragma.

{...}).

function printReplacement

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void printReplacement(
    llvm::raw_ostream & Out
)

Prints a replacement omp pragma for the encapsulated pragma onto Out.

Parameters:

Out Out stream

Print replacement pragmas.

In some cases we have to modify the printed pragma. If we have a combined constructs with target, remove target because we are already running on the target device. If we have a combined construct with teams, remove teams because the runtime can decide to spawn only a single team. If we have a simd, we prepend #pragma _NEC ivdep to indicate no dependencies.

function printAddition

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void printAddition(
    llvm::raw_ostream & Out
)

function isReplaceable

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static bool isReplaceable(
    clang::OMPExecutableDirective * Directive
)

Determines whether a pragma is replacable.

Parameters:

Directive Given Directive

Return: true If the directive is replacable

false If the directive is not replacable

function needsAdditionalPragma

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static bool needsAdditionalPragma(
    clang::OMPExecutableDirective * Directive
)

Determines whether a additional pragma is needed.

Parameters:

Directive given directive

Return: true Directive needs an additional pragma

false Directive does not need an additional pragma

Private Functions Documentation

function isClausePrintable

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bool isClausePrintable(
    clang::OMPClause * Clause
)

Determine whether a clause is printable.

Parameters:

Clause Clause to check

Return: true If the clause is printable

false If the clause is not printable

Checks for a clause the clause kind and determines which clauses are printable.

function rewriteParam

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void rewriteParam(
    std::string * In
)

Rewrite clause parameters.

Parameters:

In Parameter as string (everything in brackets)

Rewrites OMP clause parameters if they are variables to replace the variable name with the one we will use as the function argument.

function printClauses

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void printClauses(
    llvm::raw_ostream & Out
)

Print OMP Clauses.

Parameters:

Out Out stream

Private Attributes Documentation

variable PP

1	`clang::PrintingPolicy PP;`

variable Clauses

1	`llvm::ArrayRef< clang::OMPClause * > Clauses;`

variable Kind

1	`clang::OpenMPDirectiveKind Kind;`

variable ClauseParamCounter

1	`unsigned int ClauseParamCounter;`

Last update: 2021-11-24