Struct PseudoMersenneModReduce 

pub struct PseudoMersenneModReduce { /* private fields */ }

Modular reduction verification for BigUint for pseudo Mersenne moduli.

This circuit verifies that:

a = quotient * (2^modulus_po2 - modulus_subtrahend) + remainder

where modulus_po2 is additionally restricted to be a multiple of limb size to only split BigUint at limb boundaries.

This algorithm is more efficient than ModReduce when modulus_subtrahend is a short compared to modulus_po2. This is the case for many practically interesting prime field.

Implementations

impl PseudoMersenneModReduce

pub fn new( builder: &CircuitBuilder, a: &BigUint, modulus_po2: usize, modulus_subtrahend: &BigUint, quotient: &BigUint, remainder: &BigUint, ) -> Self

Creates a new pseudo Mersenne modular reduction verifier circuit.

Arguments

• builder - Circuit builder for constraint generation
• a - The dividend
• modulus_po2 - the power of two modulus minuend (has to be a multiple of Word::BITS)
• modulus_subtrahend - the value subtracted form 2^modulus_po2 to obtain modulus
• quotient - The quotient
• remainder - The remainder

Constraints

The circuit enforces that a = quotient * (2^modulus_po2 - modulus_subtrahend) + remainder. Remainder range check (0 <= remainder < 2^modulus_po2 - modulus_subtrahend) is not enforced.

Note: This adds arithmetic constraints for computing intermediate values (multiplication, addition, subtraction), but does NOT add the final equality constraint. You must call .constrain() or .constrain_cond() to enforce that the equation actually holds.

pub fn constrain(self, builder: &CircuitBuilder)

Apply the reduction constraint unconditionally.

pub fn constrain_cond(self, builder: &CircuitBuilder, cond: Wire)

Apply the reduction constraint conditionally based on the value of boolean mask wire.