Struct Incr

pub struct Incr {
    pub input: Col<B8>,
    pub carry_in: Col<B1>,
    pub output: Col<B8>,
    pub carry_out: Col<B1>,
    pub merged: Col<B32>,
}

Represents an increment operation with carry in a lookup table.

This struct holds columns for an 8-bit increment operation where:

• input is the 8-bit value to be incremented
• carry_in is a 1-bit carry input
• output is the 8-bit result of the increment
• carry_out is a 1-bit carry output
• merged is a 32-bit encoding of all inputs and outputs for lookup

The increment operation computes: output = input + carry_in, with carry_out set if the result overflows 8 bits.

Fields

input: Col<B8>

carry_in: Col<B1>

output: Col<B8>

carry_out: Col<B1>

merged: Col<B32>

Implementations

impl Incr

pub fn new( table: &mut TableBuilder<'_>, lookup_chan: ChannelId, input: Col<B8>, carry_in: Col<B1>, ) -> Self

Constructs a new increment gadget, registering the necessary columns in the table.

Arguments

• table - The table builder to register columns with.
• lookup_chan - The channel for lookup operations.
• input - The input column (8 bits).
• carry_in - The carry-in column (1 bit).

Returns

An Incr struct with all columns set up.

pub fn populate<P>( &self, witness: &mut TableWitnessSegment<'_, P>, ) -> Result<()>

where P: PackedFieldIndexable<Scalar = B128> + PackedExtension<B1> + PackedExtension<B8> + PackedExtension<B32>,

Populates the witness segment for this increment operation.

Arguments

• witness - The witness segment to populate.

Returns

Ok(()) if successful, or an error otherwise.