cuda/src/range_curate_cuda/_runtime/phase52_kernel.cu

// Phase52: warp-parallel frozen normalization, then original B matching/evaluation.
// All exceptional rows replay the unchanged serial normalizer on one GPU lane.
// Input/output semantics, 2x arenas, raw streams and taxonomy packing retain B.

#define MAX_CANDIDATES 128
#define MAX_CONJUNCTIONS 32
#define PHASE32B_POOL_BYTES 29973u

struct Candidate { int kind, index, start, end; };

__device__ __forceinline__ bool token(unsigned char c) {
    return (c >= 'a' && c <= 'z') || (c >= '0' && c <= '9') || c == '_';
}
__device__ __forceinline__ bool exact_token(unsigned char c) {
    return token(c) || (c >= 'A' && c <= 'Z');
}
__device__ __forceinline__ unsigned char lower(unsigned char c) {
    return c >= 'A' && c <= 'Z' ? c + 32 : c;
}
__device__ __forceinline__ unsigned char normalize(unsigned char c) {
    c = lower(c);
    if (c == '-' || c == '.' || c == ',' || c == ':' || c == ';' ||
        c == '(' || c == ')' || c == '[' || c == ']' || c == '{' ||
        c == '}' || c == '/') return ' ';
    return c == '`' ? '\'' : c;
}
__device__ __forceinline__ bool space(unsigned char c) {
    return c == ' ' || (c >= 9 && c <= 13) || (c >= 0x1c && c <= 0x1f);
}

// All candidate identities are unique before the fixed-size buffer is used.
// An overflow transfers the whole row to CPU; no partial result is retained.
__device__ bool append_hit(
    int key, int start, int end, const int* key_offsets,
    const int* key_consumers, const int* consumers,
    Candidate* candidates, int* count, unsigned char* conjunctions
) {
    for (int i = key_offsets[key]; i < key_offsets[key + 1]; ++i) {
        const int* spec = consumers + key_consumers[i] * 4;
        if (spec[0] == 2) {
            conjunctions[spec[1]] |= (unsigned char)(1u << spec[2]);
            continue;
        }
        bool duplicate = false;
        for (int j = 0; j < *count; ++j) {
            Candidate prior = candidates[j];
            if (prior.kind == spec[0] && prior.index == spec[1] &&
                prior.start == start && prior.end == end) {
                duplicate = true; break;
            }
        }
        if (duplicate) continue;
        if (*count == MAX_CANDIDATES) return false;
        candidates[*count] = Candidate{spec[0], spec[1], start, end};
        ++*count;
    }
    return true;
}

__device__ int lower_bound_offset(const unsigned int* offsets, int n, int value) {
    int left = 0, right = n;
    while (left < right) {
        int middle = left + (right - left) / 2;
        if (offsets[middle] < (unsigned int)value) left = middle + 1;
        else right = middle;
    }
    return left;
}
__device__ bool contains_term(
    const unsigned char* text, int left, int right, int term,
    const unsigned char* term_bytes, const int* term_offsets
) {
    int first = term_offsets[term], length = term_offsets[term + 1] - first;
    if (!length || right - left < length) return false;
    for (int start = left; start + length <= right; ++start) {
        if (start > left && token(text[start - 1])) continue;
        if (start + length < right && token(text[start + length])) continue;
        int i = 0;
        while (i < length && text[start + i] == term_bytes[first + i]) ++i;
        if (i == length) return true;
    }
    return false;
}
__device__ void context_bounds(
    const unsigned char* normalized, const unsigned int* offsets, int norm_length,
    int source_length, int start, int end, int width, int* left, int* right
) {
    int source_left = start > width ? start - width : 0;
    int source_right = width > source_length - end ? source_length : end + width;
    *left = lower_bound_offset(offsets, norm_length, source_left);
    *right = lower_bound_offset(offsets, norm_length, source_right);
    // Match Phase24's borrowed-window treatment of collapsed leading spaces.
    if (*left < *right && normalized[*left] == ' ') ++*left;
}
__device__ bool alias_context_ok(
    int context, const int* contexts, const int* clauses, const int* term_ids,
    const unsigned char* term_bytes, const int* term_offsets,
    const unsigned char* normalized, const unsigned int* offsets, int norm_length,
    int source_length, int start, int end
) {
    if (context < 0) return true;
    const int* spec = contexts + context * 5;
    int left, right;
    context_bounds(normalized, offsets, norm_length, source_length,
                   start, end, spec[0], &left, &right);
    for (int i = 0; i < spec[4]; ++i)
        if (contains_term(normalized, left, right, term_ids[spec[3] + i],
                          term_bytes, term_offsets)) return false;
    for (int i = 0; i < spec[2]; ++i) {
        const int* clause = clauses + 2 * (spec[1] + i);
        bool accepted = true;
        for (int j = 0; j < clause[1]; ++j) {
            if (!contains_term(normalized, left, right, term_ids[clause[0] + j],
                               term_bytes, term_offsets)) {
                accepted = false; break;
            }
        }
        if (accepted) return true;
    }
    return false;
}


// Strict UTF-8 scalar decoder. Zero width rejects the entire row.
__device__ __forceinline__ int phase32b_decode(
    const unsigned char* raw, int length, int position, unsigned int* scalar
) {
    unsigned int first = raw[position];
    if (first < 0x80) { *scalar = first; return 1; }
    int width;
    unsigned int value, minimum;
    if (first >= 0xc2 && first <= 0xdf) { width = 2; value = first & 31; minimum = 0x80; }
    else if (first >= 0xe0 && first <= 0xef) { width = 3; value = first & 15; minimum = 0x800; }
    else if (first >= 0xf0 && first <= 0xf4) { width = 4; value = first & 7; minimum = 0x10000; }
    else return 0;
    if (width > length - position) return 0;
    for (int index = 1; index < width; ++index) {
        unsigned int next = raw[position + index];
        if ((next & 0xc0) != 0x80) return 0;
        value = (value << 6) | (next & 63);
    }
    if (value < minimum || value > 0x10ffff || (value >= 0xd800 && value <= 0xdfff)) return 0;
    *scalar = value;
    return width;
}

// Frozen U13 mapping output is decoded into scalars before RANGE postprocessing.
// Directly copying pool bytes would skip punctuation and whitespace semantics.
__device__ bool phase32b_emit_scalar(
    unsigned int scalar, int source_index, const unsigned char* whitespace,
    unsigned char* normalized, unsigned int* offsets, int capacity,
    int* norm_length, bool* pending_space
) {
    switch (scalar) {
        case 0x2d: case 0x2010: case 0x2011: case 0x2012: case 0x2013:
        case 0x2014: case 0x2015: case 0x2212:
        case 0x2e: case 0x2c: case 0x3a: case 0x3b: case 0x28: case 0x29:
        case 0x5b: case 0x5d: case 0x7b: case 0x7d: case 0xff0f: case 0x2f:
            scalar = 32; break;
        case 0x27: case 0x2019: case 0x2018: case 0x201b: case 0x60: case 0xb4:
            scalar = 39; break;
    }
    bool is_space = scalar < 128 ? space((unsigned char)scalar) :
        ((whitespace[scalar >> 3] & (1u << (scalar & 7))) != 0);
    if (is_space) {
        *pending_space = *norm_length != 0;
        return true;
    }
    unsigned char encoded[4];
    int width;
    if (scalar < 0x80) {
        width = 1; encoded[0] = (unsigned char)scalar;
    } else if (scalar < 0x800) {
        width = 2; encoded[0] = 0xc0 | (scalar >> 6);
        encoded[1] = 0x80 | (scalar & 63);
    } else if (scalar < 0x10000) {
        width = 3; encoded[0] = 0xe0 | (scalar >> 12);
        encoded[1] = 0x80 | ((scalar >> 6) & 63);
        encoded[2] = 0x80 | (scalar & 63);
    } else {
        width = 4; encoded[0] = 0xf0 | (scalar >> 18);
        encoded[1] = 0x80 | ((scalar >> 12) & 63);
        encoded[2] = 0x80 | ((scalar >> 6) & 63);
        encoded[3] = 0x80 | (scalar & 63);
    }
    // Check the complete scalar and optional separator before either is written.
    int required = width + (*pending_space ? 1 : 0);
    if (required > capacity - *norm_length) return false;
    if (*pending_space) {
        normalized[*norm_length] = ' ';
        offsets[(*norm_length)++] = source_index;
        *pending_space = false;
    }
    for (int unit = 0; unit < width; ++unit) {
        normalized[*norm_length] = encoded[unit];
        offsets[(*norm_length)++] = source_index;
    }
    return true;
}


// Exceptional rows replay B's original ordered decoder/mapping/capacity logic.
// Successful speculative tiles may already have written a prefix; replay starts
// at zero and overwrites it. No speculative failing tile is ever published.
__device__ unsigned char phase52_serial_normalize(
    const unsigned char* raw, int length, const unsigned int* unicode_index,
    const unsigned char* unicode_pool, const unsigned char* python_whitespace,
    unsigned char* normalized, unsigned int* offsets, int norm_capacity,
    int* output_length, int* output_source_length
) {
    int norm_length = 0, source_length = 0;
    bool pending_space = false;
    for (int i = 0; i < length;) {
        unsigned int scalar;
        int width = phase32b_decode(raw, length, i, &scalar);
        if (!width) { return 5; }
        // Original-text Python ignorecase semantics retain these four extras.
        // Keep the entire original row on CPU rather than approximate raw matching.
        if (scalar == 0x0130 || scalar == 0x0131 || scalar == 0x017f || scalar == 0x212a) {
            return 2;
        }
        if (scalar < 128) {
            if (!phase32b_emit_scalar(normalize((unsigned char)scalar), source_length,
                    python_whitespace, normalized, offsets, norm_capacity, &norm_length, &pending_space)) {
                return 6;
            }
        } else {
            unsigned int mapping = unicode_index[scalar];
            if (mapping == 0) {
                if (!phase32b_emit_scalar(scalar, source_length, python_whitespace,
                        normalized, offsets, norm_capacity, &norm_length, &pending_space)) {
                    return 6;
                }
            } else {
                // The host binds exact asset hashes. Retain device range/decoder
                // guards as a fail-closed corruption check, not a fallback route.
                if (mapping > PHASE32B_POOL_BYTES - 2u) { return 7; }
                int mapped_bytes = (int)unicode_pool[mapping] | ((int)unicode_pool[mapping + 1] << 8);
                if ((unsigned int)mapped_bytes > PHASE32B_POOL_BYTES - mapping - 2u) {
                    return 7;
                }
                const unsigned char* mapped = unicode_pool + mapping + 2;
                for (int position = 0; position < mapped_bytes;) {
                    unsigned int mapped_scalar;
                    int mapped_width = phase32b_decode(mapped, mapped_bytes, position, &mapped_scalar);
                    if (!mapped_width) { return 7; }
                    if (!phase32b_emit_scalar(mapped_scalar, source_length, python_whitespace,
                            normalized, offsets, norm_capacity, &norm_length, &pending_space)) {
                        return 6;
                    }
                    position += mapped_width;
                }
            }
        }
        i += width;
        ++source_length;
    }

    *output_length = norm_length;
    *output_source_length = source_length;
    return 0;
}

// A lane owns one original scalar's post-mapping piece. Its scratch payload is
// trimmed at both ends, with internal spaces collapsed. All its eventual bytes
// have the same original source offset, including internal collapsed separators.
// The two end flags preserve whitespace that trimming removes; they are needed
// when this piece is composed with preceding/following original scalars.
#define PHASE52_MAX_PIECE_BYTES 33
#define PHASE52_SCRATCH_BYTES 34
#define PHASE52_WARPS_PER_BLOCK 4
#define PHASE52_FULL_MASK 0xffffffffu

__device__ __forceinline__ bool phase52_piece_scalar(
    unsigned int scalar, const unsigned char* whitespace, unsigned char* piece,
    int* length, bool* pending, bool* seen_unit, bool* leading_space, bool* trailing_space
) {
    switch (scalar) {
        case 0x2d: case 0x2010: case 0x2011: case 0x2012: case 0x2013:
        case 0x2014: case 0x2015: case 0x2212:
        case 0x2e: case 0x2c: case 0x3a: case 0x3b: case 0x28: case 0x29:
        case 0x5b: case 0x5d: case 0x7b: case 0x7d: case 0xff0f: case 0x2f:
            scalar = 32; break;
        case 0x27: case 0x2019: case 0x2018: case 0x201b: case 0x60: case 0xb4:
            scalar = 39; break;
    }
    bool is_space = scalar < 128 ? space((unsigned char)scalar) :
        ((whitespace[scalar >> 3] & (1u << (scalar & 7))) != 0);
    if (!*seen_unit) { *seen_unit = true; *leading_space = is_space; }
    *trailing_space = is_space;
    if (is_space) { *pending = *length != 0; return true; }
    unsigned char encoded[4];
    int width;
    if (scalar < 0x80) {
        width = 1; encoded[0] = (unsigned char)scalar;
    } else if (scalar < 0x800) {
        width = 2; encoded[0] = 0xc0 | (scalar >> 6);
        encoded[1] = 0x80 | (scalar & 63);
    } else if (scalar < 0x10000) {
        width = 3; encoded[0] = 0xe0 | (scalar >> 12);
        encoded[1] = 0x80 | ((scalar >> 6) & 63);
        encoded[2] = 0x80 | (scalar & 63);
    } else {
        width = 4; encoded[0] = 0xf0 | (scalar >> 18);
        encoded[1] = 0x80 | ((scalar >> 12) & 63);
        encoded[2] = 0x80 | ((scalar >> 6) & 63);
        encoded[3] = 0x80 | (scalar & 63);
    }
    if (width + (*pending ? 1 : 0) > PHASE52_MAX_PIECE_BYTES - *length) return false;
    if (*pending) { piece[(*length)++ * 32] = ' '; *pending = false; }
    for (int unit = 0; unit < width; ++unit) piece[(*length)++ * 32] = encoded[unit];
    return true;
}

extern "C" __global__ void range52_normalize_warp(
    const unsigned char* data, const long long* row_offsets, int rows, int max_row_bytes,
    const unsigned int* unicode_index, const unsigned char* unicode_pool,
    const unsigned char* python_whitespace, unsigned char* normalized_data,
    unsigned int* source_offsets, int* normalized_lengths, int* source_lengths,
    unsigned char* codes, unsigned int* facts
) {
    // The host launch contract is exactly 128 threads: four independent warps.
    __shared__ unsigned char shared_payload[PHASE52_WARPS_PER_BLOCK * PHASE52_SCRATCH_BYTES * 32];
    int lane = threadIdx.x & 31, local_warp = threadIdx.x >> 5;
    int row = blockIdx.x * PHASE52_WARPS_PER_BLOCK + local_warp;
    if (row >= rows) return; // Uniform for all lanes of this warp.
    unsigned char* piece = shared_payload + local_warp * PHASE52_SCRATCH_BYTES * 32 + lane;
    unsigned int* fact = facts + (long long)row * 8;
    if (lane < 8) fact[lane] = 0;
    if (lane == 0) {
        codes[row] = 0;
        normalized_lengths[row] = source_lengths[row] = 0;
    }
    long long base = row_offsets[row], raw_length = row_offsets[row + 1] - base;
    if (raw_length > max_row_bytes) {
        if (lane == 0) codes[row] = 4;
        return;
    }
    int length = (int)raw_length, norm_capacity = length * 2;
    const unsigned char* raw = data + base;
    unsigned char* normalized = normalized_data + base * 2;
    unsigned int* offsets = source_offsets + base * 2;
    int norm_length = 0, source_length = 0;
    bool pending_space = false;
    for (int tile = 0; tile < length; tile += 32) {
        int position = tile + lane, piece_length = 0;
        bool replay = false, valid_lead = false;
        bool local_pending = false, seen_unit = false, leading_space = false, trailing_space = false;
        if (position < length) {
            unsigned char first = raw[position];
            if ((first & 0xc0) == 0x80) {
                // A continuation is an identity piece only when a strict valid
                // lead in the previous 1..3 bytes owns it. This also checks the
                // first lanes of a tile whose scalar began in the previous tile.
                bool covered = false;
                for (int back = 1; back <= 3 && back <= position; ++back) {
                    if ((raw[position - back] & 0xc0) == 0x80) continue;
                    unsigned int ignored;
                    int width = phase32b_decode(raw, length, position - back, &ignored);
                    if (width > back) { covered = true; break; }
                }
                if (!covered) replay = true;
            } else {
                unsigned int scalar;
                int width = phase32b_decode(raw, length, position, &scalar);
                if (!width) replay = true;
                else {
                    valid_lead = true;
                    if (scalar == 0x0130 || scalar == 0x0131 || scalar == 0x017f || scalar == 0x212a)
                        replay = true;
                    else if (scalar < 128) {
                        replay = !phase52_piece_scalar(normalize((unsigned char)scalar), python_whitespace,
                            piece, &piece_length, &local_pending, &seen_unit, &leading_space, &trailing_space);
                    } else {
                        unsigned int mapping = unicode_index[scalar];
                        if (!mapping) {
                            replay = !phase52_piece_scalar(scalar, python_whitespace, piece,
                                &piece_length, &local_pending, &seen_unit, &leading_space, &trailing_space);
                        } else if (mapping > PHASE32B_POOL_BYTES - 2u) replay = true;
                        else {
                            int mapped_bytes = (int)unicode_pool[mapping] | ((int)unicode_pool[mapping + 1] << 8);
                            if ((unsigned int)mapped_bytes > PHASE32B_POOL_BYTES - mapping - 2u ||
                                mapped_bytes > PHASE52_MAX_PIECE_BYTES) replay = true;
                            else {
                                const unsigned char* mapped = unicode_pool + mapping + 2;
                                for (int at = 0; at < mapped_bytes && !replay;) {
                                    unsigned int mapped_scalar;
                                    int mapped_width = phase32b_decode(mapped, mapped_bytes, at, &mapped_scalar);
                                    if (!mapped_width) replay = true;
                                    else {
                                        replay = !phase52_piece_scalar(mapped_scalar, python_whitespace, piece,
                                            &piece_length, &local_pending, &seen_unit, &leading_space, &trailing_space);
                                        at += mapped_width;
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
        // No thread leaves before a warp-wide decision. Continuation/inactive
        // lanes have empty identity summaries but still participate in every scan.
        bool replay_row = __any_sync(PHASE52_FULL_MASK, replay);
        unsigned int lower_lanes = lane == 0 ? 0u : (1u << lane) - 1u;
        unsigned int lead_mask = __ballot_sync(PHASE52_FULL_MASK, valid_lead);
        unsigned int text_mask = __ballot_sync(PHASE52_FULL_MASK, piece_length != 0);
        unsigned int effective_mask = __ballot_sync(PHASE52_FULL_MASK, seen_unit);
        unsigned int effective_before = effective_mask & lower_lanes;
        int previous_lane = effective_before ? 31 - __clz(effective_before) : 0;
        bool previous_trailing = __shfl_sync(PHASE52_FULL_MASK, (int)trailing_space, previous_lane) != 0;
        bool incoming_space = effective_before ? previous_trailing : pending_space;
        bool preceding_text = norm_length != 0 || (text_mask & lower_lanes) != 0;
        bool separator = piece_length != 0 && preceding_text && (incoming_space || leading_space);
        int emitted = piece_length + (separator ? 1 : 0);
        int inclusive = emitted;
        for (int distance = 1; distance < 32; distance <<= 1) {
            int prior = __shfl_up_sync(PHASE52_FULL_MASK, inclusive, distance);
            if (lane >= distance) inclusive += prior;
        }
        int tile_bytes = __shfl_sync(PHASE52_FULL_MASK, inclusive, 31);
        if (tile_bytes > norm_capacity - norm_length) replay_row = true;
        if (replay_row) {
            // Serial replay resolves all ordering ambiguities, including a
            // capacity error earlier than a raw4 or corrupt mapping in this tile.
            // Speculative scratch is private and this tile has not been stored.
            // Order every lane's earlier global stores before lane 0 overwrites
            // their prefix; votes/shuffles alone are not a memory barrier.
            __syncwarp(PHASE52_FULL_MASK);
            if (lane == 0) {
                int replay_length = 0, replay_source_length = 0;
                unsigned char code = phase52_serial_normalize(raw, length, unicode_index,
                    unicode_pool, python_whitespace, normalized, offsets, norm_capacity,
                    &replay_length, &replay_source_length);
                normalized_lengths[row] = replay_length;
                source_lengths[row] = replay_source_length;
                codes[row] = code;
            }
            __syncwarp(PHASE52_FULL_MASK);
            return;
        }
        int original_index = source_length + __popc(lead_mask & lower_lanes);
        int output = norm_length + inclusive - emitted;
        if (separator) {
            normalized[output] = ' ';
            offsets[output++] = original_index;
        }
        for (int unit = 0; unit < piece_length; ++unit) {
            normalized[output] = piece[unit * 32];
            offsets[output++] = original_index;
        }
        norm_length += tile_bytes;
        source_length += __popc(lead_mask);
        int final_lane = effective_mask ? 31 - __clz(effective_mask) : 0;
        bool final_trailing = __shfl_sync(PHASE52_FULL_MASK, (int)trailing_space, final_lane) != 0;
        if (effective_mask) pending_space = norm_length != 0 && final_trailing;
    }
    if (lane == 0) {
        normalized_lengths[row] = norm_length;
        source_lengths[row] = source_length;
    }
}

extern "C" __global__ void range52_match_evaluate(
    const unsigned char* data, const long long* row_offsets,
    const long long* timestamps, int rows, int max_row_bytes,
    const unsigned int* transitions, const unsigned short* classes,
    const int* dfa_meta, const int* output_offsets, const int* output_keys,
    const int* key_lengths, const int* key_offsets, const int* key_consumers,
    const int* consumers, const long long* aliases, const int* lexical,
    const int* contexts, const int* clauses, const int* term_ids,
    const unsigned char* term_bytes, const int* term_offsets,
    const unsigned int* unicode_index, const unsigned char* unicode_pool,
    const unsigned char* python_whitespace, int conjunction_count,
    unsigned char* normalized_data, unsigned int* source_offsets,
    Candidate* all_candidates, unsigned char* codes, unsigned int* facts,
    const int* normalized_lengths, const int* source_lengths
) {
    int row = blockIdx.x * blockDim.x + threadIdx.x;
    if (row >= rows || codes[row] >= 2) return;
    unsigned int* fact = facts + (long long)row * 8;
    long long base = row_offsets[row];
    int length = (int)(row_offsets[row + 1] - base);
    const unsigned char* raw = data + base;
    unsigned char* normalized = normalized_data + base * 2;
    unsigned int* offsets = source_offsets + base * 2;
    int norm_length = normalized_lengths[row], source_length = source_lengths[row];
    Candidate* candidates = all_candidates + (long long)row * MAX_CANDIDATES;
    int count = 0;
    unsigned char conjunctions[MAX_CONJUNCTIONS] = {0};
    bool native_candidate = false, exact_candidate = false;
    // Stream 0: normalized. Stream 1: raw case-sensitive. Stream 2: raw ASCII fold.
    for (int stream = 0; stream < 3; ++stream) {
        const int* meta = dfa_meta + stream * 4;
        if (meta[3] == 0) continue;
        const unsigned char* text = stream == 0 ? normalized : raw;
        int n = stream == 0 ? norm_length : length;
        unsigned int state = 0;
        int raw_source_position = -1;
        for (int pos = 0; pos < n; ++pos) {
            // Validated UTF-8; every lead/ASCII byte starts one original scalar.
            if (stream != 0 && (text[pos] & 0xc0) != 0x80) ++raw_source_position;
            unsigned char c = stream == 2 ? lower(text[pos]) : text[pos];
            state = transitions[meta[0] + state * meta[1] + classes[stream * 256 + c]];
            int first = output_offsets[meta[2] + state];
            int last = output_offsets[meta[2] + state + 1];
            for (int out = first; out < last; ++out) {
                int key = output_keys[out];
                int start = pos + 1 - key_lengths[key], end = pos + 1;
                bool left_ok = start == 0 || !(stream == 0 ? token(text[start - 1]) : exact_token(text[start - 1]));
                bool right_ok = end == n || !(stream == 0 ? token(text[end]) : exact_token(text[end]));
                if (!left_ok || !right_ok) continue;
                if (stream == 0) native_candidate = true;
                else exact_candidate = true;
                // Raw keys remain ASCII: a hit spans key_lengths[key] scalars.
                // Compatibility mappings never enter either raw matching stream.
                int original_end = stream == 0 ? offsets[end - 1] + 1 : raw_source_position + 1;
                int original_start = stream == 0 ? offsets[start] : original_end - key_lengths[key];
                if (!append_hit(key, original_start, original_end, key_offsets,
                                key_consumers, consumers, candidates, &count, conjunctions)) {
                    codes[row] = 3; return;
                }
            }
        }
    }

    bool accepted_nonsemantic = false, accepted_evidence = false;
    bool unresolved_exposure = false, unresolved_event = false;
    unsigned int supported = 0, observations = 0;
    for (int i = 0; i < count; ++i) {
        Candidate candidate = candidates[i];
        if (candidate.kind == 0) {
            const long long* alias = aliases + candidate.index * 8;
            bool longest = true;
            for (int j = 0; j < count; ++j) {
                Candidate other = candidates[j];
                if (other.kind == 0 && other.start == candidate.start &&
                    aliases[other.index * 8] == alias[0] && other.end > candidate.end) {
                    longest = false; break;
                }
            }
            if (!longest) continue;
            ++observations; // Retained observations count before temporal/context checks.
            if (timestamps[row] < alias[1] || (alias[3] && timestamps[row] >= alias[2])) continue;
            if (!alias_context_ok((int)alias[7], contexts, clauses, term_ids,
                                  term_bytes, term_offsets, normalized, offsets,
                                  norm_length, source_length, candidate.start, candidate.end)) continue;
            accepted_nonsemantic = true;
            if (alias[4] != -1 && (alias[5] == 0 || alias[5] == 1)) {
                accepted_evidence = true; supported |= 1u << alias[4];
            } else if (alias[6]) unresolved_exposure = true;
        } else {
            const int* rule = lexical + candidate.index * 7;
            ++observations;
            bool context_ok = rule[2] == 0;
            if (!context_ok) {
                int left, right;
                context_bounds(normalized, offsets, norm_length, source_length,
                               candidate.start, candidate.end, rule[0], &left, &right);
                for (int j = 0; j < rule[2]; ++j) {
                    if (contains_term(normalized, left, right, term_ids[rule[1] + j],
                                      term_bytes, term_offsets)) { context_ok = true; break; }
                }
            }
            if (rule[3]) {
                if (rule[4]) { accepted_evidence = true; supported |= 8; }
                else { if (rule[5]) unresolved_exposure = true; if (rule[6]) unresolved_event = true; }
            } else {
                if (context_ok) accepted_nonsemantic = true;
                if (rule[4] && context_ok) { accepted_evidence = true; supported |= 8; }
                else if (rule[5]) unresolved_exposure = true;
            }
        }
    }
    for (int i = 0; i < conjunction_count; ++i) {
        if (conjunctions[i] == 15) { ++observations; accepted_evidence = true; supported |= 8; }
    }
    if (!observations) return;
    fact[0] = accepted_evidence || accepted_nonsemantic || unresolved_event ? 0 : 2;
    for (int family = 0; family < 4; ++family)
        fact[family + 1] = supported & (1u << family) ? 0 :
            (family != 3 && !supported && unresolved_exposure ? 1 : 2);
    fact[5] = observations; fact[6] = native_candidate; fact[7] = exact_candidate;
    codes[row] = 1;
}