sdfg::transformations::LoopSplit Class Reference

Loop splitting transformation at a symbolic boundary. More...

#include <sdfg/transformations/loop_split.h>

Inheritance diagram for sdfg::transformations::LoopSplit:

Public Member Functions
	LoopSplit (structured_control_flow::StructuredLoop &loop, const symbolic::Expression &split_point)
	Construct a loop split transformation.
virtual std::string	name () const override
	Get the name of this transformation.
virtual bool	can_be_applied (builder::StructuredSDFGBuilder &builder, analysis::AnalysisManager &analysis_manager) override
	Check if this transformation can be safely applied.
virtual void	apply (builder::StructuredSDFGBuilder &builder, analysis::AnalysisManager &analysis_manager) override
	Apply this transformation to the SDFG.
virtual void	to_json (nlohmann::json &j) const override
	Serialize this transformation to JSON.
Public Member Functions inherited from sdfg::transformations::Transformation
virtual	~Transformation ()=default
virtual void	set_report (PassReportConsumer *report)
	Set the report consumer for transformation feedback.
virtual bool	try_apply (builder::StructuredSDFGBuilder &builder, analysis::AnalysisManager &analysis_manager)
	Attempt to apply the transformation if possible.

Static Public Member Functions
static LoopSplit	from_json (builder::StructuredSDFGBuilder &builder, const nlohmann::json &j)

Additional Inherited Members
Protected Attributes inherited from sdfg::transformations::Transformation
PassReportConsumer *	report_ = nullptr

Detailed Description

Loop splitting transformation at a symbolic boundary.

Splits a single loop into two consecutive loops at the same nesting level, partitioning the iteration space at a symbolic split point.

Given: for (i = init; i < bound; i = update) { body }

Produces: for (i = init; i < split_point; i = update) { body_copy } for (i = split_point; i < bound; i = update) { body }

The split point is an arbitrary symbolic expression (e.g., an enclosing loop's induction variable). The transformation is always semantically correct — it is an identity on the iteration space: [init, bound) = [init, split_point) ∪ [split_point, bound)

If split_point <= init, the first loop is empty (zero iterations). If split_point >= bound, the second loop is empty (zero iterations).

Note

The loop must be contiguous (stride == 1)

The loop condition must be a simple strict-less-than (indvar < bound)

The split_point must be a valid symbolic expression in scope

Primary use case: enabling LoopDistribute on triangular loop nests (e.g., splitting k in [0, i) at i_tile0 for blocked LU factorization).

Constructor & Destructor Documentation

LoopSplit()

sdfg::transformations::LoopSplit::LoopSplit	(	structured_control_flow::StructuredLoop &	loop,
		const symbolic::Expression &	split_point )

Construct a loop split transformation.

Parameters

loop	The loop to split
split_point	Symbolic expression at which to split the iteration space

Member Function Documentation

apply()

virtual void sdfg::transformations::LoopSplit::apply ( builder::StructuredSDFGBuilder & builder, analysis::AnalysisManager & analysis_manager )

overridevirtual

Apply this transformation to the SDFG.

Parameters

builder	The SDFG builder
analysis_manager	The analysis manager (may be invalidated)

Implements sdfg::transformations::Transformation.

can_be_applied()

virtual bool sdfg::transformations::LoopSplit::can_be_applied ( builder::StructuredSDFGBuilder & builder, analysis::AnalysisManager & analysis_manager )

overridevirtual

Check if this transformation can be safely applied.

Parameters

builder	The SDFG builder
analysis_manager	The analysis manager providing necessary analyses

Returns

true if all preconditions are met

Implements sdfg::transformations::Transformation.

from_json()

LoopSplit sdfg::transformations::LoopSplit::from_json ( builder::StructuredSDFGBuilder & builder, const nlohmann::json & j )

static

name()

virtual std::string sdfg::transformations::LoopSplit::name ( ) const

overridevirtual

Get the name of this transformation.

Returns

The transformation name (e.g., "LoopInterchange")

Implements sdfg::transformations::Transformation.

to_json()

virtual void sdfg::transformations::LoopSplit::to_json ( nlohmann::json & j ) const

overridevirtual

Serialize this transformation to JSON.

Parameters

j	JSON object to populate with transformation description

Exceptions

std::logic_error

if not implemented

Implements sdfg::transformations::Transformation.

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The documentation for this class was generated from the following file:

• opt/include/sdfg/transformations/loop_split.h