#include </home/runner/work/Sleipnir/Sleipnir/include/sleipnir/autodiff/expression.hpp>

Public Types
using	Scalar = Scalar_
	Scalar type alias.

Public Member Functions
constexpr	Expression ()=default
	Constructs a constant expression with a value of zero.

constexpr	Expression (Scalar value)

constexpr bool	is_constant (Scalar constant) const

virtual void	visit_args (function_ref< void(Expression< Scalar > *arg)> func) const

virtual Scalar	value () const =0

virtual ExpressionType	type () const =0

virtual std::string_view	name () const =0

virtual void	accumulate_adjoints () const
	Accumulates the child adjoints as Scalars.

virtual void	accumulate_adjoints_expr () const
	Accumulates the child adjoints as Expressions.

Public Attributes
Scalar	val {0}
	The value of the expression node.

Scalar	adj {0}
	The adjoint of the expression node, used during autodiff.

ExpressionPtr< Scalar >	adj_expr

bool	is_leaf = false

int32_t	scratch = -1

uint32_t	ref_count = 0
	Reference count for intrusive shared pointer.

Friends
ExpressionPtr< Scalar >	operator* (const ExpressionPtr< Scalar > &lhs, const ExpressionPtr< Scalar > &rhs)

ExpressionPtr< Scalar >	operator/ (const ExpressionPtr< Scalar > &lhs, const ExpressionPtr< Scalar > &rhs)

ExpressionPtr< Scalar >	operator+ (const ExpressionPtr< Scalar > &lhs, const ExpressionPtr< Scalar > &rhs)

ExpressionPtr< Scalar >	operator+= (ExpressionPtr< Scalar > &lhs, const ExpressionPtr< Scalar > &rhs)

ExpressionPtr< Scalar >	operator- (const ExpressionPtr< Scalar > &lhs, const ExpressionPtr< Scalar > &rhs)

ExpressionPtr< Scalar >	operator- (const ExpressionPtr< Scalar > &lhs)

ExpressionPtr< Scalar >	operator+ (const ExpressionPtr< Scalar > &lhs)

Detailed Description

template<typename Scalar_>
struct slp::detail::Expression< Scalar_ >

An autodiff expression node.

Template Parameters

Scalar Scalar type.

Constructor & Destructor Documentation

◆ Expression()

template<typename Scalar_ >

constexpr slp::detail::Expression< Scalar_ >::Expression ( Scalar value )

inlineexplicitconstexpr

Constructs a nullary expression (an operator with no arguments).

Parameters

value The expression value.

Member Function Documentation

◆ accumulate_adjoints()

template<typename Scalar_ >

virtual void slp::detail::Expression< Scalar_ >::accumulate_adjoints ( ) const

inlinevirtual

Accumulates the child adjoints as Scalars.

◆ accumulate_adjoints_expr()

template<typename Scalar_ >

virtual void slp::detail::Expression< Scalar_ >::accumulate_adjoints_expr ( ) const

inlinevirtual

Accumulates the child adjoints as Expressions.

◆ is_constant()

template<typename Scalar_ >

constexpr bool slp::detail::Expression< Scalar_ >::is_constant ( Scalar constant ) const

inlineconstexpr

Returns true if the expression is the given constant.

Parameters

constant The constant.

Returns: True if the expression is the given constant.

◆ name()

template<typename Scalar_ >

virtual std::string_view slp::detail::Expression< Scalar_ >::name ( ) const

pure virtual

Returns the name of this expression.

Returns: The name of this expression.

◆ type()

template<typename Scalar_ >

virtual ExpressionType slp::detail::Expression< Scalar_ >::type ( ) const

pure virtual

Returns the type of this expression (constant, linear, quadratic, or nonlinear).

Returns: The type of this expression.

◆ value()

template<typename Scalar_ >

virtual Scalar slp::detail::Expression< Scalar_ >::value ( ) const

pure virtual

Either nullary operator with no arguments, unary operator with one argument, or binary operator with two arguments. This operator is used to update the node's value.

Returns: The node's value.

◆ visit_args()

template<typename Scalar_ >

virtual void slp::detail::Expression< Scalar_ >::visit_args ( function_ref< void(Expression< Scalar > *arg)> func ) const

inlinevirtual

Runs a function on each argument.

Parameters

func	The function to run.

Friends And Related Symbol Documentation

◆ operator*

template<typename Scalar_ >

ExpressionPtr< Scalar > operator*	(	const ExpressionPtr< Scalar > &	lhs,
		const ExpressionPtr< Scalar > &	rhs
	)

friend

Expression-Expression multiplication operator.

Parameters

lhs	Operator left-hand side.
rhs	Operator right-hand side.

◆ operator+ [1/2]

template<typename Scalar_ >

ExpressionPtr< Scalar > operator+ ( const ExpressionPtr< Scalar > & lhs )

friend

Unary plus operator.

Parameters

lhs	Operand of unary plus.

◆ operator+ [2/2]

template<typename Scalar_ >

ExpressionPtr< Scalar > operator+	(	const ExpressionPtr< Scalar > &	lhs,
		const ExpressionPtr< Scalar > &	rhs
	)

friend

Expression-Expression addition operator.

Parameters

lhs	Operator left-hand side.
rhs	Operator right-hand side.

◆ operator+=

template<typename Scalar_ >

ExpressionPtr< Scalar > operator+=	(	ExpressionPtr< Scalar > &	lhs,
		const ExpressionPtr< Scalar > &	rhs
	)

friend

Expression-Expression compound addition operator.

Parameters

lhs	Operator left-hand side.
rhs	Operator right-hand side.

◆ operator- [1/2]

template<typename Scalar_ >

ExpressionPtr< Scalar > operator- ( const ExpressionPtr< Scalar > & lhs )

friend

Unary minus operator.

Parameters

lhs	Operand of unary minus.

◆ operator- [2/2]

template<typename Scalar_ >

ExpressionPtr< Scalar > operator-	(	const ExpressionPtr< Scalar > &	lhs,
		const ExpressionPtr< Scalar > &	rhs
	)

friend

Expression-Expression subtraction operator.

Parameters

lhs	Operator left-hand side.
rhs	Operator right-hand side.

◆ operator/

template<typename Scalar_ >

ExpressionPtr< Scalar > operator/	(	const ExpressionPtr< Scalar > &	lhs,
		const ExpressionPtr< Scalar > &	rhs
	)

friend

Expression-Expression division operator.

Parameters

lhs	Operator left-hand side.
rhs	Operator right-hand side.

Member Data Documentation

◆ adj_expr

template<typename Scalar_ >

ExpressionPtr<Scalar> slp::detail::Expression< Scalar_ >::adj_expr

The adjoint of the expression node, used during gradient expression tree generation.

◆ is_leaf

template<typename Scalar_ >

bool slp::detail::Expression< Scalar_ >::is_leaf = false

True if the expression is a leaf node (a nullary expression).

Graph traversals check this to avoid virtual calls on leaves. The check also feeds the branch predictor history that helps it predict the virtual call targets of non-leaf nodes.

◆ scratch

template<typename Scalar_ >

int32_t slp::detail::Expression< Scalar_ >::scratch = -1

Scratch space for various graph algorithms.

In expression_graph.hpp's topological_sort(), scratch counts incoming edges for this node, offset by -1 so -1 means no edges.

In Hessian and Jacobian constructors, scratch represents this expression's column in a Jacobian, or -1 otherwise.

They share a default state of -1 to avoid extra assignments.

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

/home/runner/work/Sleipnir/Sleipnir/include/sleipnir/autodiff/expression.hpp

Public Types

Public Member Functions

Public Attributes

Friends

Detailed Description

Constructor & Destructor Documentation

◆ Expression()

Member Function Documentation

◆ accumulate_adjoints()

◆ accumulate_adjoints_expr()

◆ is_constant()

◆ name()

◆ type()

◆ value()

◆ visit_args()

Friends And Related Symbol Documentation

◆ operator*

◆ operator+ [1/2]

◆ operator+ [2/2]

◆ operator+=

◆ operator- [1/2]

◆ operator- [2/2]

◆ operator/

Member Data Documentation

◆ adj_expr

◆ is_leaf

◆ scratch