P4HashFunction Struct Reference

Inheritance diagram for P4HashFunction:

Public Member Functions
void	dbprint (std::ostream &out) const
bool	equiv (const P4HashFunction *) const
bool	equiv_dyn (const P4HashFunction *func) const
bool	equiv_inputs_alg (const P4HashFunction *func) const
bool	is_dynamic () const
bool	is_next_bit_of_hash (const P4HashFunction *) const
cstring	name () const
bool	overlap (const P4HashFunction *, le_bitrange *my_overlap, le_bitrange *hash_overlap) const
int	size () const
void	slice (le_bitrange hash_slice)
Public Member Functions inherited from P4::IHasDbPrint
void	print () const

Public Attributes
IR::MAU::HashFunction	algorithm
cstring	dyn_hash_name
le_bitrange	hash_bits
const IR::Expression *	hash_gen_expr = nullptr
safe_vector< const IR::Expression * >	inputs
LTBitMatrix	symmetrically_hashed_inputs

Member Function Documentation

dbprint()

void P4HashFunction::dbprint ( std::ostream & out ) const

virtual

Implements P4::IHasDbPrint.

equiv_inputs_alg()

bool P4HashFunction::equiv_inputs_alg

(

const P4HashFunction *

func

)

const

Much tighter than the actual constraint, as things like identity functions could check for better overlaps as well as random functions wouldn't matter in terms of order, but this can be expanded much later on. This will work quickly for dynamic hashing

overlap()

bool P4HashFunction::overlap	(	const P4HashFunction *	func,
		le_bitrange *	my_overlap,
		le_bitrange *	hash_overlap ) const

This hash function overlap is based on the equiv function which is much more strict than an actual equiv function. This may be further improved at a later time, but will also work quickly with anything dynamic

slice()

void P4HashFunction::slice

(

le_bitrange

hash_slice

)

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Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

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SPDX-License-Identifier: Apache-2.0