Struct AllocatedEmulatedFpVar

pub struct AllocatedEmulatedFpVar<TargetF: PrimeField, BaseF: PrimeField> {
    pub cs: ConstraintSystemRef<BaseF>,
    pub limbs: Vec<FpVar<BaseF>>,
    pub num_of_additions_over_normal_form: BaseF,
    pub is_in_the_normal_form: bool,
    /* private fields */
}

The allocated version of EmulatedFpVar (introduced below)

Fields

cs: ConstraintSystemRef<BaseF>

Constraint system reference

limbs: Vec<FpVar<BaseF>>

The limbs, each of which is a BaseF gadget.

num_of_additions_over_normal_form: BaseF

Number of additions done over this gadget, using which the gadget decides when to reduce.

is_in_the_normal_form: bool

Whether the limb representation is the normal form (using only the bits specified in the parameters, and the representation is strictly within the range of TargetF).

Implementations

impl<TargetF: PrimeField, BaseF: PrimeField> AllocatedEmulatedFpVar<TargetF, BaseF>

pub fn cs(&self) -> ConstraintSystemRef<BaseF>

Return cs

pub fn limbs_to_value( limbs: Vec<BaseF>, optimization_type: OptimizationType, ) -> TargetF

Obtain the value of limbs

pub fn value(&self) -> R1CSResult<TargetF>

Obtain the value of a emulated field element

pub fn constant( cs: ConstraintSystemRef<BaseF>, value: TargetF, ) -> R1CSResult<Self>

Obtain the emulated field element of a constant value

pub fn one(cs: ConstraintSystemRef<BaseF>) -> R1CSResult<Self>

Obtain the emulated field element of one

pub fn zero(cs: ConstraintSystemRef<BaseF>) -> R1CSResult<Self>

Obtain the emulated field element of zero

pub fn add(&self, other: &Self) -> R1CSResult<Self>

Add a emulated field element

pub fn add_constant(&self, other: &TargetF) -> R1CSResult<Self>

Add a constant

pub fn sub_without_reduce(&self, other: &Self) -> R1CSResult<Self>

Subtract a emulated field element, without the final reduction step

pub fn sub(&self, other: &Self) -> R1CSResult<Self>

Subtract a emulated field element

pub fn sub_constant(&self, other: &TargetF) -> R1CSResult<Self>

Subtract a constant

pub fn mul(&self, other: &Self) -> R1CSResult<Self>

Multiply a emulated field element

pub fn mul_constant(&self, other: &TargetF) -> R1CSResult<Self>

Multiply a constant

pub fn negate(&self) -> R1CSResult<Self>

Compute the negate of a emulated field element

pub fn inverse(&self) -> R1CSResult<Self>

Compute the inverse of a emulated field element

pub fn get_limbs_representations( elem: &TargetF, optimization_type: OptimizationType, ) -> R1CSResult<Vec<BaseF>>

Convert a TargetF element into limbs (not constraints) This is an internal function that would be reused by a number of other functions

pub fn get_limbs_representations_from_big_integer( elem: &<TargetF as PrimeField>::BigInt, optimization_type: OptimizationType, ) -> R1CSResult<Vec<BaseF>>

Obtain the limbs directly from a big int

pub fn mul_without_reduce( &self, other: &Self, ) -> R1CSResult<AllocatedMulResultVar<TargetF, BaseF>>

for advanced use, multiply and output the intermediate representations (without reduction) This intermediate representations can be added with each other, and they can later be reduced back to the EmulatedFpVar.

pub fn new_witness_with_le_bits<T: Borrow<TargetF>>( cs: impl Into<Namespace<BaseF>>, f: impl FnOnce() -> Result<T, SynthesisError>, ) -> R1CSResult<(Self, Vec<Boolean<BaseF>>)>

Allocates a new non-native field witness with value given by the function f. Enforces that the field element has value in [0, modulus), and returns the bits of its binary representation. The bits are in little-endian (i.e., the bit at index 0 is the LSB) and the bit-vector is empty in non-witness allocation modes.

Trait Implementations

impl<TargetF: PrimeField, BaseF: PrimeField> AllocVar<TargetF, BaseF> for AllocatedEmulatedFpVar<TargetF, BaseF>

fn new_variable<T: Borrow<TargetF>>( cs: impl Into<Namespace<BaseF>>, f: impl FnOnce() -> Result<T, SynthesisError>, mode: AllocationMode, ) -> R1CSResult<Self>

Allocates a new variable of type Self in the ConstraintSystem cs. The mode of allocation is decided by mode.

fn new_constant( cs: impl Into<Namespace<F>>, t: impl Borrow<V>, ) -> Result<Self, SynthesisError>

Allocates a new constant of type Self in the ConstraintSystem cs.

fn new_input<T: Borrow<V>>( cs: impl Into<Namespace<F>>, f: impl FnOnce() -> Result<T, SynthesisError>, ) -> Result<Self, SynthesisError>

Allocates a new public input of type Self in the ConstraintSystem cs.

fn new_witness<T: Borrow<V>>( cs: impl Into<Namespace<F>>, f: impl FnOnce() -> Result<T, SynthesisError>, ) -> Result<Self, SynthesisError>

Allocates a new private witness of type Self in the ConstraintSystem cs.

fn new_variable_with_inferred_mode<T: Borrow<V>>( cs: impl Into<Namespace<F>>, f: impl FnOnce() -> Result<T, SynthesisError>, ) -> Result<Self, SynthesisError>

Allocates a new constant or private witness of type Self in the ConstraintSystem cs with the allocation mode inferred from cs. A constant is allocated if cs is None, and a private witness is allocated otherwise.

impl<TargetF: PrimeField, BaseF: PrimeField> Clone for AllocatedEmulatedFpVar<TargetF, BaseF>

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<TargetF: PrimeField, BaseF: PrimeField> CondSelectGadget<BaseF> for AllocatedEmulatedFpVar<TargetF, BaseF>

fn conditionally_select( cond: &Boolean<BaseF>, true_value: &Self, false_value: &Self, ) -> R1CSResult<Self>

If cond == &Boolean::TRUE, then this returns true_value; else, returns false_value.

fn conditionally_select_power_of_two_vector( position: &[Boolean<ConstraintF>], values: &[Self], ) -> Result<Self, SynthesisError>

Returns an element of values whose index in represented by position. position is an array of boolean that represents an unsigned integer in big endian order.

impl<TargetF: Debug + PrimeField, BaseF: Debug + PrimeField> Debug for AllocatedEmulatedFpVar<TargetF, BaseF>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<TargetF: PrimeField, BaseF: PrimeField> From<&AllocatedEmulatedFpVar<TargetF, BaseF>> for AllocatedMulResultVar<TargetF, BaseF>

fn from(src: &AllocatedEmulatedFpVar<TargetF, BaseF>) -> Self

Converts to this type from the input type.

impl<TargetF: PrimeField, BaseF: PrimeField> From<AllocatedEmulatedFpVar<TargetF, BaseF>> for EmulatedFpVar<TargetF, BaseF>

fn from(other: AllocatedEmulatedFpVar<TargetF, BaseF>) -> Self

Converts to this type from the input type.

impl<TargetF: PrimeField, BaseF: PrimeField> ThreeBitCondNegLookupGadget<BaseF> for AllocatedEmulatedFpVar<TargetF, BaseF>

type TableConstant = TargetF

The type of values being looked up.

fn three_bit_cond_neg_lookup( bits: &[Boolean<BaseF>], b0b1: &Boolean<BaseF>, constants: &[Self::TableConstant], ) -> R1CSResult<Self>

Interprets the slice bits as a two-bit integer b = bits[0] + (bits[1] << 1), and then outputs constants[b] * c, where c = if bits[2] { -1 } else { 1 };.

impl<TargetF: PrimeField, BaseF: PrimeField> ToBitsGadget<BaseF> for AllocatedEmulatedFpVar<TargetF, BaseF>

fn to_bits_le(&self) -> R1CSResult<Vec<Boolean<BaseF>>>

Outputs the canonical little-endian bit-wise representation of self.

fn to_non_unique_bits_le(&self) -> Result<Vec<Boolean<F>>, SynthesisError>

Outputs a possibly non-unique little-endian bit-wise representation of self.

fn to_bits_be(&self) -> Result<Vec<Boolean<F>>, SynthesisError>

Outputs the canonical big-endian bit-wise representation of self.

fn to_non_unique_bits_be(&self) -> Result<Vec<Boolean<F>>, SynthesisError>

Outputs a possibly non-unique big-endian bit-wise representation of self.

impl<TargetF: PrimeField, BaseF: PrimeField> ToBytesGadget<BaseF> for AllocatedEmulatedFpVar<TargetF, BaseF>

fn to_bytes_le(&self) -> R1CSResult<Vec<UInt8<BaseF>>>

Outputs a canonical, little-endian, byte decomposition of self.

fn to_non_unique_bytes_le(&self) -> Result<Vec<UInt8<F>>, SynthesisError>

Outputs a possibly non-unique byte decomposition of self.

impl<TargetF: PrimeField, BaseF: PrimeField> ToConstraintFieldGadget<BaseF> for AllocatedEmulatedFpVar<TargetF, BaseF>

fn to_constraint_field(&self) -> R1CSResult<Vec<FpVar<BaseF>>>

Converts self to FpVar<ConstraintF> variables.

impl<TargetF: PrimeField, BaseF: PrimeField> TwoBitLookupGadget<BaseF> for AllocatedEmulatedFpVar<TargetF, BaseF>

type TableConstant = TargetF

The type of values being looked up.

fn two_bit_lookup( bits: &[Boolean<BaseF>], constants: &[Self::TableConstant], ) -> R1CSResult<Self>

Interprets the slice bits as a two-bit integer b = bits[0] + (bits[1] << 1), and then outputs constants[b].