amrex::Parser Class Reference

Front-end for parsing scalar expressions into GPU/CPU executors. More...

#include <AMReX_Parser.H>

Public Member Functions
	Parser (std::string const &func_body)
	Construct a parser by immediately parsing func_body.
	Parser ()=default
	Default-construct; call define() before compilation.
void	define (std::string const &func_body)
	Parse and own a new expression, replacing any previous state.
	operator bool () const
	True when an expression has been parsed successfully.
void	setConstant (std::string const &name, double c)
	Bind a named constant to c.
void	registerVariables (Vector< std::string > const &vars)
	Register the ordered list of variable names used by the expression.
void	registerUserFn1 (std::string const &name, ParserUserFn1 fh, ParserUserFn1 fd)
	Register a user-defined unary function available to expressions.
void	registerUserFn2 (std::string const &name, ParserUserFn2 fh, ParserUserFn2 fd)
	Register a user-defined binary function.
void	registerUserFn3 (std::string const &name, ParserUserFn3 fh, ParserUserFn3 fd)
	Register a user-defined ternary function.
void	registerUserFn4 (std::string const &name, ParserUserFn4 fh, ParserUserFn4 fd)
	Register a user-defined function with four arguments.
void	print () const
	Print a human-readable representation of the parser tree to stdout.
void	printExe () const
	Dump the compiled bytecode to stdout for debugging.
int	depth () const
	Return the maximum tree depth of the parsed expression.
int	maxStackSize () const
	Return the maximum stack usage recorded during compilation.
std::string	expr () const
	Return the sanitized expression string currently managed by the Parser.
std::set< std::string >	symbols () const
	Return the set of symbols (variables and functions) referenced by the expression.
std::map< std::string, int > const &	userFunctions () const
	Access the map of registered user-defined functions.
template<int N>
ParserExecutor< N >	compile () const
	Compile the current expression into a host/device executor.
template<int N>
ParserExecutor< N >	compileHost () const
	Compile the current expression into a host-only executor.

Detailed Description

Front-end for parsing scalar expressions into GPU/CPU executors.

A Parser instance owns the expression string, parser state, and registered variables. After calling define(), registerVariables(), and (optionally) registerUserFn*, the expression can be compiled into a ParserExecutor that evaluates it efficiently on host or device.

Different Parser objects may be constructed or defined concurrently from multiple host threads. For parallel evaluation, prefer sharing the compiled ParserExecutor across threads instead of constructing one Parser per thread.

Constructor & Destructor Documentation

Parser() [1/2]

amrex::Parser::Parser

(

std::string const &

func_body

)

Construct a parser by immediately parsing func_body.

Parameters

func_body

Expression text; pass an empty string to defer parsing.

Parser() [2/2]

amrex::Parser::Parser ( )

default

Default-construct; call define() before compilation.

Member Function Documentation

compile()

template<int N>

ParserExecutor< N > amrex::Parser::compile

(

)

const

Compile the current expression into a host/device executor.

Template Parameters

N	Number of registered variables.

Returns

ParserExecutor callable on both host and GPU (if available).

compileHost()

template<int N>

ParserExecutor< N > amrex::Parser::compileHost

(

)

const

Compile the current expression into a host-only executor.

Template Parameters

N	Number of registered variables.

Returns

ParserExecutor that executes only on the host.

define()

void amrex::Parser::define

(

std::string const &

func_body

)

Parse and own a new expression, replacing any previous state.

Parameters

func_body

Expression text to parse.

depth()

int amrex::Parser::depth

(

)

const

Return the maximum tree depth of the parsed expression.

Returns

Depth measured in parse-tree levels (0 if undefined).

expr()

std::string amrex::Parser::expr

(

)

const

Return the sanitized expression string currently managed by the Parser.

Returns

Copy of the parsed expression, or an empty string if undefined.

maxStackSize()

int amrex::Parser::maxStackSize

(

)

const

Return the maximum stack usage recorded during compilation.

Returns

Stack depth in parser instructions (0 if undefined).

operator bool()

amrex::Parser::operator bool ( ) const

explicit

True when an expression has been parsed successfully.

print()

void amrex::Parser::print

(

)

const

Print a human-readable representation of the parser tree to stdout.

printExe()

void amrex::Parser::printExe

(

)

const

Dump the compiled bytecode to stdout for debugging.

registerUserFn1()

void amrex::Parser::registerUserFn1	(	std::string const &	name,
		ParserUserFn1	fh,
		ParserUserFn1	fd
	)

Register a user-defined unary function available to expressions.

Parameters

name	Function identifier used inside expressions.
fh	Host function pointer (double(double)).
fd	Device function pointer (double(double)); may be nullptr on CPU-only builds.

registerUserFn2()

void amrex::Parser::registerUserFn2	(	std::string const &	name,
		ParserUserFn2	fh,
		ParserUserFn2	fd
	)

Register a user-defined binary function.

Parameters

name	Function identifier.
fh	Host implementation taking two doubles.
fd	Device implementation taking two doubles; may be nullptr on CPU builds.

registerUserFn3()

void amrex::Parser::registerUserFn3	(	std::string const &	name,
		ParserUserFn3	fh,
		ParserUserFn3	fd
	)

Register a user-defined ternary function.

Parameters

name	Function identifier.
fh	Host implementation taking three doubles.
fd	Device implementation taking three doubles; may be nullptr on CPU builds.

registerUserFn4()

void amrex::Parser::registerUserFn4	(	std::string const &	name,
		ParserUserFn4	fh,
		ParserUserFn4	fd
	)

Register a user-defined function with four arguments.

Parameters

name	Function identifier.
fh	Host implementation taking four doubles.
fd	Device implementation taking four doubles; may be nullptr on CPU builds.

registerVariables()

void amrex::Parser::registerVariables

(

Vector< std::string > const &

vars

)

Register the ordered list of variable names used by the expression.

The ordering determines how arguments are passed to ParserExecutor::operator().

Parameters

vars	Variable names supplied in parser argument order.

setConstant()

void amrex::Parser::setConstant	(	std::string const &	name,
		double	c
	)

Bind a named constant to c.

Parameters

name	Identifier referenced inside the expression.
c	Constant value substituted when compiling.

symbols()

std::set< std::string > amrex::Parser::symbols

(

)

const

Return the set of symbols (variables and functions) referenced by the expression.

Returns

Alphabetically sorted symbol names.

userFunctions()

std::map< std::string, int > const & amrex::Parser::userFunctions

(

)

const

Access the map of registered user-defined functions.

Returns

Map from function name to argument count.

---

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

• /home/runner/work/amrex/amrex/Src/Base/Parser/AMReX_Parser.H
• /home/runner/work/amrex/amrex/Src/Base/Parser/AMReX_Parser.cpp