libsnark::tbcs_gate Class Reference

#include <tbcs.hpp>

Public Member Functions
bool	evaluate (const tbcs_variable_assignment &input) const
void	print (const std::map< size_t, std::string > &variable_annotations=std::map< size_t, std::string >()) const
bool	operator== (const tbcs_gate &other) const

Public Attributes
tbcs_wire_t	left_wire
tbcs_wire_t	right_wire
tbcs_gate_type	type
tbcs_wire_t	output
bool	is_circuit_output

Friends
std::ostream &	operator<< (std::ostream &out, const tbcs_gate &g)
std::istream &	operator>> (std::istream &in, tbcs_gate &g)

Detailed Description

A TBCS gate is a formal expression of the form

           g(left_wire,right_wire) = output ,

where 'left_wire' and 'right_wire' are the two input wires, and 'output' is the output wire. In other words, a TBCS gate is a 2-input boolean gate; there are 16 possible such gates (see tbcs_gate_type above).

A TBCS gate is used to construct a TBCS circuit (see below).

Definition at line 87 of file tbcs.hpp.

Member Function Documentation

evaluate()

bool libsnark::tbcs_gate::evaluate

(

const tbcs_variable_assignment &

input

)

const

This function is very tricky. See comment in tbcs.hpp .

Definition at line 24 of file tbcs.cpp.

{
    const bool X = (left_wire == 0 ? true : input[left_wire - 1]);
    const bool Y = (right_wire == 0 ? true : input[right_wire - 1]);
 
    // 3 - ... inverts position
    const size_t pos = 3 - ((X ? 2 : 0) + (Y ? 1 : 0));
 
    return (((int)type) & (1u << pos));
}

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operator==()

bool libsnark::tbcs_gate::operator==

(

const tbcs_gate &

other

)

const

Definition at line 125 of file tbcs.cpp.

{
    return (
        this->left_wire == other.left_wire &&
        this->right_wire == other.right_wire && this->type == other.type &&
        this->output == other.output &&
        this->is_circuit_output == other.is_circuit_output);
}

print()

void libsnark::tbcs_gate::print

(

const std::map< size_t, std::string > &

variable_annotations = std::map<size_t, std::string>()

)

const

Definition at line 60 of file tbcs.cpp.

{
    switch (this->type) {
    case TBCS_GATE_CONSTANT_0:
        printf("CONSTANT_0");
        break;
    case TBCS_GATE_AND:
        printf("AND");
        break;
    case TBCS_GATE_X_AND_NOT_Y:
        printf("X_AND_NOT_Y");
        break;
    case TBCS_GATE_X:
        printf("X");
        break;
    case TBCS_GATE_NOT_X_AND_Y:
        printf("NOT_X_AND_Y");
        break;
    case TBCS_GATE_Y:
        printf("Y");
        break;
    case TBCS_GATE_XOR:
        printf("XOR");
        break;
    case TBCS_GATE_OR:
        printf("OR");
        break;
    case TBCS_GATE_NOR:
        printf("NOR");
        break;
    case TBCS_GATE_EQUIVALENCE:
        printf("EQUIVALENCE");
        break;
    case TBCS_GATE_NOT_Y:
        printf("NOT_Y");
        break;
    case TBCS_GATE_IF_Y_THEN_X:
        printf("IF_Y_THEN_X");
        break;
    case TBCS_GATE_NOT_X:
        printf("NOT_X");
        break;
    case TBCS_GATE_IF_X_THEN_Y:
        printf("IF_X_THEN_Y");
        break;
    case TBCS_GATE_NAND:
        printf("NAND");
        break;
    case TBCS_GATE_CONSTANT_1:
        printf("CONSTANT_1");
        break;
    default:
        printf("Invalid type");
    }
 
    printf("\n(\n");
    print_tbcs_wire(left_wire, variable_annotations);
    printf(",\n");
    print_tbcs_wire(right_wire, variable_annotations);
    printf("\n) ->\n");
    print_tbcs_wire(output, variable_annotations);
    printf(" (%s)\n", is_circuit_output ? "circuit output" : "internal wire");
}

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Friends And Related Function Documentation

operator<<

std::ostream& operator<< ( std::ostream &  out, const tbcs_gate &  g  )

friend

Definition at line 134 of file tbcs.cpp.

{
    out << g.left_wire << "\n";
    out << g.right_wire << "\n";
    out << (int)g.type << "\n";
    out << g.output << "\n";
    libff::output_bool(out, g.is_circuit_output);
 
    return out;
}

operator>>

std::istream& operator>> ( std::istream &  in, tbcs_gate &  g  )

friend

Definition at line 145 of file tbcs.cpp.

{
    in >> g.left_wire;
    libff::consume_newline(in);
    in >> g.right_wire;
    libff::consume_newline(in);
    int tmp;
    in >> tmp;
    g.type = (tbcs_gate_type)tmp;
    libff::consume_newline(in);
    in >> g.output;
    libff::input_bool(in, g.is_circuit_output);
 
    return in;
}

Member Data Documentation

is_circuit_output

bool libsnark::tbcs_gate::is_circuit_output

Definition at line 97 of file tbcs.hpp.

left_wire

tbcs_wire_t libsnark::tbcs_gate::left_wire

Definition at line 90 of file tbcs.hpp.

output

tbcs_wire_t libsnark::tbcs_gate::output

Definition at line 95 of file tbcs.hpp.

right_wire

tbcs_wire_t libsnark::tbcs_gate::right_wire

Definition at line 91 of file tbcs.hpp.

type

tbcs_gate_type libsnark::tbcs_gate::type

Definition at line 93 of file tbcs.hpp.

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

• /home/runner/work/libsnark/libsnark/libsnark/relations/circuit_satisfaction_problems/tbcs/tbcs.hpp
• /home/runner/work/libsnark/libsnark/libsnark/relations/circuit_satisfaction_problems/tbcs/tbcs.cpp