ecc_msm_relation.hpp

Go to the documentation of this file.

// === AUDIT STATUS ===
// internal:    { status: Complete, auditors: [Raju], commit: 2a49eb6 }
// external_1:  { status: not started, auditors: [], commit: }
// external_2:  { status: not started, auditors: [], commit: }
// =====================
 
#pragma once
#include "barretenberg/relations/relation_types.hpp"
 
namespace bb {
 
template <typename FF_> class ECCVMMSMRelationImpl {
  public:
    using FF = FF_;
 
    // Named subrelation indices — matches SUBRELATION_PARTIAL_LENGTHS ordering.
    // Grouped by logical function within the Strauss MSM algorithm.
    enum SubrelationIndex : size_t {
        // Addition round: accumulator update and slope constraints
        ADD_ACC_X = 0,
        ADD_ACC_Y = 1,
        ADD_SLOPE_1 = 2,
        // Skew round: accumulator update and slope constraint
        SKEW_ACC_X = 3,
        SKEW_ACC_Y = 4,
        SKEW_SLOPE_1 = 5,
        // Collision checks: x-coordinate non-equality for point additions
        COLLISION_CHECK_1 = 6,
        COLLISION_CHECK_2 = 7,
        COLLISION_CHECK_3 = 8,
        COLLISION_CHECK_4 = 9,
        // Doubling round: accumulator update and slope constraint
        DOUBLE_ACC_X = 10,
        DOUBLE_ACC_Y = 11,
        DOUBLE_SLOPE_1 = 12,
        // Inactive slice zeroing: force slice_i = 0 when add_i = 0
        INACTIVE_SLICE_1 = 13,
        INACTIVE_SLICE_2 = 14,
        INACTIVE_SLICE_3 = 15,
        INACTIVE_SLICE_4 = 16,
        // Phase selector mutual exclusivity: at most one of q_add, q_double, q_skew active
        PHASE_SELECTOR_MUTUAL_EXCLUSIVITY = 17,
        // Round transition forces round_delta == 1
        ROUND_TRANSITION_FORCES_DELTA_ONE = 18,
        // Round transition with skew implies round == 31
        ROUND_TRANSITION_SKEW_IMPLIES_ROUND_31 = 19,
        // Round transition requires exactly one of double or skew on next row
        ROUND_TRANSITION_EXACTLY_ONE_DOUBLE_OR_SKEW = 20,
        // Round transition needs double or skew (cannot have neither)
        ROUND_TRANSITION_NEEDS_DOUBLE_OR_SKEW = 21,
        // Double implies next row is an add row
        DOUBLE_IMPLIES_NEXT_IS_ADD = 22,
        // Count shift must be zero when round changes
        COUNT_SHIFT_ZERO_ON_ROUND_CHANGE = 23,
        // Count increments within the same round by number of active adds
        COUNT_INCREMENT_WITHIN_ROUND = 24,
        // Count must be zero at round boundary or MSM transition
        COUNT_ZERO_AT_ROUND_BOUNDARY_OR_TRANSITION = 25,
        // MSM transition implies round = 0
        MSM_TRANSITION_ROUND_ZERO = 26,
        // MSM transition: pc = pc_shift + msm_size
        MSM_TRANSITION_PC = 27,
        // Addition continuity: add2 requires add1
        ADD_CONTINUITY_2 = 28,
        // Addition continuity: add3 requires add2
        ADD_CONTINUITY_3 = 29,
        // Addition continuity: add4 requires add3
        ADD_CONTINUITY_4 = 30,
        // Cross-row continuity: if add spans two rows, add4 must be 1
        ADD_CROSS_ROW_CONTINUITY = 31,
        // add1 = q_add + q_skew
        ADD1_DECOMPOSITION = 32,
        // q_skew persists until MSM transition: q_skew && !msm_transition_shift => q_skew_shift
        SKEW_PERSISTS_UNTIL_MSM_TRANSITION = 33,
        // q_skew implies round == 32
        SKEW_IMPLIES_ROUND_32 = 34,
        // Doubling requires a round change (round_delta must be 1 if q_double_shift)
        DOUBLE_REQUIRES_ROUND_CHANGE = 35,
        // Additional addition slope constraints (split to prevent cancellation)
        ADD_SLOPE_2 = 36,
        ADD_SLOPE_3 = 37,
        ADD_SLOPE_4 = 38,
        // Additional doubling slope constraints (split to prevent cancellation)
        DOUBLE_SLOPE_2 = 39,
        DOUBLE_SLOPE_3 = 40,
        DOUBLE_SLOPE_4 = 41,
        // Additional skew slope constraints (split to prevent cancellation)
        SKEW_SLOPE_2 = 42,
        SKEW_SLOPE_3 = 43,
        SKEW_SLOPE_4 = 44,
        // Idle row: accumulator preserved when no phase selector is active
        IDLE_ROW_PRESERVES_ACC_X = 45,
        IDLE_ROW_PRESERVES_ACC_Y = 46,
        NUM_SUBRELATIONS,
    };
 
    static constexpr std::array<size_t, 47> SUBRELATION_PARTIAL_LENGTHS{ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
                                                                         8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
                                                                         8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 };
    static_assert(NUM_SUBRELATIONS == SUBRELATION_PARTIAL_LENGTHS.size());
 
    template <typename ContainerOverSubrelations, typename AllEntities, typename Parameters>
    static void accumulate(ContainerOverSubrelations& accumulator,
                           const AllEntities& in,
                           const Parameters& /* unused */,
                           const FF& scaling_factor);
};
 
template <typename FF> using ECCVMMSMRelation = Relation<ECCVMMSMRelationImpl<FF>>;
 
} // namespace bb