ActionData::Constant Class Reference

#include <action_format.h>

Inheritance diagram for ActionData::Constant:

Public Member Functions
	Constant (bitvec v, size_t sz)
	Constant (int v, size_t sz)
cstring	alias () const
void	dbprint (std::ostream &out) const override
bool	equiv_value (const Parameter *ad, bool check_cond=true) const override
bool	from_p4_program () const override
const Parameter *	get_extended_param (uint32_t extension, const Parameter *ad) const override
bool	is_next_bit_of_param (const Parameter *ad, bool same_alias) const override
cstring	name () const override
bool	only_one_overlap_solution () const override
const Parameter *	overlap (const Parameter *ad, bool only_one_overlap_solution, le_bitrange *my_overlap, le_bitrange *ad_overlap) const override
void	set_alias (cstring a)
int	size () const override
const Parameter *	split (int lo, int hi) const override
bitvec	value () const
Public Member Functions inherited from ActionData::Parameter
virtual bool	can_merge (const Parameter *param) const
bool	can_overlap_ranges (le_bitrange my_range, le_bitrange ad_range, le_bitrange &overlap, le_bitrange *my_overlap, le_bitrange *ad_overlap) const
cstring	cond_name () const
bool	equiv_cond (const Parameter *p) const
template<typename T >
bool	is () const
bool	is_cond_type (ModConditionally_t type) const
virtual bool	is_subset_of (const Parameter *param) const
virtual const Parameter *	merge (const Parameter *param) const
void	set_cond (const Parameter *p)
void	set_cond (ModConditionally_t ct, cstring n)
template<typename T >
const T *	to () const
Public Member Functions inherited from P4::IHasDbPrint
void	print () const

Additional Inherited Members
Protected Attributes inherited from ActionData::Parameter
cstring	_cond_name
ModConditionally_t	_cond_type = NONE

Detailed Description

This class represents a section of IR::MAU::ActionDataConstant, or an IR::Constant that cannot be created as the src1 operand of an ALU operation. The constant instead must come from Action Ram.

Similar to IR::Constant, the constant has a value and a bit size. Due to the size of the constant theoretically being infinite, a bitvec is used to store the value (though in theory, an mpz_class could have been used as well

Member Function Documentation

dbprint()

void P4::IR::Constant::dbprint ( std::ostream & out ) const

inlineoverridevirtual

Implements ActionData::Parameter.

equiv_value()

bool ActionData::Constant::equiv_value ( const Parameter * ad, bool check_cond = true ) const

overridevirtual

Implements ActionData::Parameter.

from_p4_program()

bool ActionData::Constant::from_p4_program ( ) const

inlineoverridevirtual

Implements ActionData::Parameter.

get_extended_param()

const Parameter * ActionData::Constant::get_extended_param ( uint32_t extension, const Parameter * ad ) const

overridevirtual

Appending a constant to another constant on the MSB

Implements ActionData::Parameter.

is_next_bit_of_param()

bool ActionData::Constant::is_next_bit_of_param ( const Parameter * ad, bool same_alias ) const

overridevirtual

If the constant is coming from an argument, it has an alias. If the same alias is set to true, then only return true if the current constant has the same alias as the next constant

Implements ActionData::Parameter.

name()

cstring ActionData::Constant::name ( ) const

inlineoverridevirtual

Implements ActionData::Parameter.

only_one_overlap_solution()

bool ActionData::Constant::only_one_overlap_solution ( ) const

inlineoverridevirtual

Implements ActionData::Parameter.

overlap()

const Parameter * ActionData::Constant::overlap ( const Parameter * ad, bool only_one_overlap_solution, le_bitrange * my_overlap, le_bitrange * ad_overlap ) const

overridevirtual

Because Constants can potentially have multiple overlaps, this will only return an overlap under the following condition:

The constant that is smaller size than the other constant must be fully contained
within the other constant.

This could possibly be updated overtime to allow for more constant processing, i.e. overlaps at the edges of the constant

The parameter only_one_overlap_solution indicates that the overlap function will only return if overlap has one and only one solution (as this function is used by multiple Parameters). Constants do not have this property and will always return a no solution

Implements ActionData::Parameter.

size()

int ActionData::Constant::size ( ) const

inlineoverridevirtual

Implements ActionData::Parameter.

split()

const Parameter * ActionData::Constant::split ( int lo, int hi ) const

overridevirtual

Implements ActionData::Parameter.