Use separate logic output muxing vectors for each decoder

[pulseview.git] / pv / data / logicsegment.cpp

/*
 * This file is part of the PulseView project.
 *
 * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#include "config.h" // For HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS

#include <extdef.h>

#include <cassert>
#include <cmath>
#include <cstdlib>
#include <cstring>
#include <cstdint>

#include "logic.hpp"
#include "logicsegment.hpp"

#include <libsigrokcxx/libsigrokcxx.hpp>

using std::lock_guard;
using std::recursive_mutex;
using std::max;
using std::min;
using std::shared_ptr;
using std::vector;

using sigrok::Logic;

namespace pv {
namespace data {

const int LogicSegment::MipMapScalePower = 4;
const int LogicSegment::MipMapScaleFactor = 1 << MipMapScalePower;
const float LogicSegment::LogMipMapScaleFactor = logf(MipMapScaleFactor);
const uint64_t LogicSegment::MipMapDataUnit = 64 * 1024; // bytes

LogicSegment::LogicSegment(pv::data::Logic& owner, uint32_t segment_id,
        unsigned int unit_size, uint64_t samplerate) :
        Segment(segment_id, samplerate, unit_size),
        owner_(owner),
        last_append_sample_(0),
        last_append_accumulator_(0),
        last_append_extra_(0)
{
        memset(mip_map_, 0, sizeof(mip_map_));
}

LogicSegment::~LogicSegment()
{
        lock_guard<recursive_mutex> lock(mutex_);

        for (MipMapLevel &l : mip_map_)
                free(l.data);
}

shared_ptr<const LogicSegment> LogicSegment::get_shared_ptr() const
{
        shared_ptr<const Segment> ptr = nullptr;

        try {
                ptr = shared_from_this();
        } catch (std::exception& e) {
                /* Do nothing, ptr remains a null pointer */
        }

        return ptr ? std::dynamic_pointer_cast<const LogicSegment>(ptr) : nullptr;
}

template <class T>
void LogicSegment::downsampleTmain(const T*&in, T &acc, T &prev)
{
        // Accumulate one sample at a time
        for (uint64_t i = 0; i < MipMapScaleFactor; i++) {
                T sample = *in++;
                acc |= prev ^ sample;
                prev = sample;
        }
}

template <>
void LogicSegment::downsampleTmain<uint8_t>(const uint8_t*&in, uint8_t &acc, uint8_t &prev)
{
        // Handle 8 bit samples in 32 bit steps
        uint32_t prev32 = prev | prev << 8 | prev << 16 | prev << 24;
        uint32_t acc32 = acc;
        const uint32_t *in32 = (const uint32_t*)in;
        for (uint64_t i = 0; i < MipMapScaleFactor; i += 4) {
                uint32_t sample32 = *in32++;
                acc32 |= prev32 ^ sample32;
                prev32 = sample32;
        }
        // Reduce result back to uint8_t
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
        prev = (prev32 >> 24) & 0xff; // MSB is last
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
        prev = prev32 & 0xff; // LSB is last
#else
#error Endianness unknown
#endif
        acc |= acc32 & 0xff;
        acc |= (acc32 >> 8) & 0xff;
        acc |= (acc32 >> 16) & 0xff;
        acc |= (acc32 >> 24) & 0xff;
        in = (const uint8_t*)in32;
}

template <>
void LogicSegment::downsampleTmain<uint16_t>(const uint16_t*&in, uint16_t &acc, uint16_t &prev)
{
        // Handle 16 bit samples in 32 bit steps
        uint32_t prev32 = prev | prev << 16;
        uint32_t acc32 = acc;
        const uint32_t *in32 = (const uint32_t*)in;
        for (uint64_t i = 0; i < MipMapScaleFactor; i += 2) {
                uint32_t sample32 = *in32++;
                acc32 |= prev32 ^ sample32;
                prev32 = sample32;
        }
        // Reduce result back to uint16_t
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
        prev = (prev32 >> 16) & 0xffff; // MSB is last
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
        prev = prev32 & 0xffff; // LSB is last
#else
#error Endian unknown
#endif
        acc |= acc32 & 0xffff;
        acc |= (acc32 >> 16) & 0xffff;
        in = (const uint16_t*)in32;
}

template <class T>
void LogicSegment::downsampleT(const uint8_t *in_, uint8_t *&out_, uint64_t len)
{
        const T *in = (const T*)in_;
        T *out = (T*)out_;
        T prev = last_append_sample_;
        T acc = last_append_accumulator_;

        // Try to complete the previous downsample
        if (last_append_extra_) {
                while (last_append_extra_ < MipMapScaleFactor && len > 0) {
                        T sample = *in++;
                        acc |= prev ^ sample;
                        prev = sample;
                        last_append_extra_++;
                        len--;
                }
                if (!len) {
                        // Not enough samples available to complete downsample
                        last_append_sample_ = prev;
                        last_append_accumulator_ = acc;
                        return;
                }
                // We have a complete downsample
                *out++ = acc;
                acc = 0;
                last_append_extra_ = 0;
        }

        // Handle complete blocks of MipMapScaleFactor samples
        while (len >= MipMapScaleFactor) {
                downsampleTmain<T>(in, acc, prev);
                len -= MipMapScaleFactor;
                // Output downsample
                *out++ = acc;
                acc = 0;
        }

        // Process remainder, not enough for a complete sample
        while (len > 0) {
                T sample = *in++;
                acc |= prev ^ sample;
                prev = sample;
                last_append_extra_++;
                len--;
        }

        // Update context
        last_append_sample_ = prev;
        last_append_accumulator_ = acc;
        out_ = (uint8_t *)out;
}

void LogicSegment::downsampleGeneric(const uint8_t *in, uint8_t *&out, uint64_t len)
{
        // Downsample using the generic unpack_sample()
        // which can handle any width between 1 and 8 bytes
        uint64_t prev = last_append_sample_;
        uint64_t acc = last_append_accumulator_;

        // Try to complete the previous downsample
        if (last_append_extra_) {
                while (last_append_extra_ < MipMapScaleFactor && len > 0) {
                        const uint64_t sample = unpack_sample(in);
                        in += unit_size_;
                        acc |= prev ^ sample;
                        prev = sample;
                        last_append_extra_++;
                        len--;
                }
                if (!len) {
                        // Not enough samples available to complete downsample
                        last_append_sample_ = prev;
                        last_append_accumulator_ = acc;
                        return;
                }
                // We have a complete downsample
                pack_sample(out, acc);
                out += unit_size_;
                acc = 0;
                last_append_extra_ = 0;
        }

        // Handle complete blocks of MipMapScaleFactor samples
        while (len >= MipMapScaleFactor) {
                // Accumulate one sample at a time
                for (uint64_t i = 0; i < MipMapScaleFactor; i++) {
                        const uint64_t sample = unpack_sample(in);
                        in += unit_size_;
                        acc |= prev ^ sample;
                        prev = sample;
                }
                len -= MipMapScaleFactor;
                // Output downsample
                pack_sample(out, acc);
                out += unit_size_;
                acc = 0;
        }

        // Process remainder, not enough for a complete sample
        while (len > 0) {
                const uint64_t sample = unpack_sample(in);
                in += unit_size_;
                acc |= prev ^ sample;
                prev = sample;
                last_append_extra_++;
                len--;
        }

        // Update context
        last_append_sample_ = prev;
        last_append_accumulator_ = acc;
}

inline uint64_t LogicSegment::unpack_sample(const uint8_t *ptr) const
{
#ifdef HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
        return *(uint64_t*)ptr;
#else
        uint64_t value = 0;
        switch (unit_size_) {
        default:
                value |= ((uint64_t)ptr[7]) << 56;
                /* FALLTHRU */
        case 7:
                value |= ((uint64_t)ptr[6]) << 48;
                /* FALLTHRU */
        case 6:
                value |= ((uint64_t)ptr[5]) << 40;
                /* FALLTHRU */
        case 5:
                value |= ((uint64_t)ptr[4]) << 32;
                /* FALLTHRU */
        case 4:
                value |= ((uint32_t)ptr[3]) << 24;
                /* FALLTHRU */
        case 3:
                value |= ((uint32_t)ptr[2]) << 16;
                /* FALLTHRU */
        case 2:
                value |= ptr[1] << 8;
                /* FALLTHRU */
        case 1:
                value |= ptr[0];
                /* FALLTHRU */
        case 0:
                break;
        }
        return value;
#endif
}

inline void LogicSegment::pack_sample(uint8_t *ptr, uint64_t value)
{
#ifdef HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
        *(uint64_t*)ptr = value;
#else
        switch (unit_size_) {
        default:
                ptr[7] = value >> 56;
                /* FALLTHRU */
        case 7:
                ptr[6] = value >> 48;
                /* FALLTHRU */
        case 6:
                ptr[5] = value >> 40;
                /* FALLTHRU */
        case 5:
                ptr[4] = value >> 32;
                /* FALLTHRU */
        case 4:
                ptr[3] = value >> 24;
                /* FALLTHRU */
        case 3:
                ptr[2] = value >> 16;
                /* FALLTHRU */
        case 2:
                ptr[1] = value >> 8;
                /* FALLTHRU */
        case 1:
                ptr[0] = value;
                /* FALLTHRU */
        case 0:
                break;
        }
#endif
}

void LogicSegment::append_payload(shared_ptr<sigrok::Logic> logic)
{
        assert(unit_size_ == logic->unit_size());
        assert((logic->data_length() % unit_size_) == 0);

        append_payload(logic->data_pointer(), logic->data_length());
}

void LogicSegment::append_payload(void *data, uint64_t data_size)
{
        assert(unit_size_ > 0);
        assert((data_size % unit_size_) == 0);

        lock_guard<recursive_mutex> lock(mutex_);

        const uint64_t prev_sample_count = sample_count_;
        const uint64_t sample_count = data_size / unit_size_;

        append_samples(data, sample_count);

        // Generate the first mip-map from the data
        append_payload_to_mipmap();

        if (sample_count > 1)
                owner_.notify_samples_added(SharedPtrToSegment(shared_from_this()),
                        prev_sample_count + 1, prev_sample_count + 1 + sample_count);
        else
                owner_.notify_samples_added(SharedPtrToSegment(shared_from_this()),
                        prev_sample_count + 1, prev_sample_count + 1);
}

void LogicSegment::append_subsignal_payload(unsigned int index, void *data,
        uint64_t data_size, vector<uint8_t>& destination)
{
        if (index == 0)
                destination.resize(data_size * unit_size_, 0);

        // Set the bits for this sub-signal where needed
        // Note: the bytes in *data must either be 0 or 1, nothing else
        unsigned int index_byte_offs = index / 8;
        uint8_t* output_data = destination.data() + index_byte_offs;
        uint8_t* input_data = (uint8_t*)data;

        for (uint64_t i = 0; i < data_size; i++) {
                assert((i * unit_size_ + index_byte_offs) < destination.size());
                *output_data |= (input_data[i] << index);
                output_data += unit_size_;
        }

        if (index == owner_.num_channels() - 1) {
                // We gathered sample data of all sub-signals, let's append it
                append_payload(destination.data(), destination.size());
                destination.clear();
        }
}

void LogicSegment::get_samples(int64_t start_sample,
        int64_t end_sample, uint8_t* dest) const
{
        assert(start_sample >= 0);
        assert(start_sample <= (int64_t)sample_count_);
        assert(end_sample >= 0);
        assert(end_sample <= (int64_t)sample_count_);
        assert(start_sample <= end_sample);
        assert(dest != nullptr);

        lock_guard<recursive_mutex> lock(mutex_);

        get_raw_samples(start_sample, (end_sample - start_sample), dest);
}

void LogicSegment::get_subsampled_edges(
        vector<EdgePair> &edges,
        uint64_t start, uint64_t end,
        float min_length, int sig_index, bool first_change_only)
{
        uint64_t index = start;
        unsigned int level;
        bool last_sample;
        bool fast_forward;

        assert(start <= end);
        assert(min_length > 0);
        assert(sig_index >= 0);
        assert(sig_index < 64);

        lock_guard<recursive_mutex> lock(mutex_);

        // Make sure we only process as many samples as we have
        if (end > get_sample_count())
                end = get_sample_count();

        const uint64_t block_length = (uint64_t)max(min_length, 1.0f);
        const unsigned int min_level = max((int)floorf(logf(min_length) /
                LogMipMapScaleFactor) - 1, 0);
        const uint64_t sig_mask = 1ULL << sig_index;

        // Store the initial state
        last_sample = (get_unpacked_sample(start) & sig_mask) != 0;
        if (!first_change_only)
                edges.emplace_back(index++, last_sample);

        while (index + block_length <= end) {
                //----- Continue to search -----//
                level = min_level;

                // We cannot fast-forward if there is no mip-map data at
                // the minimum level.
                fast_forward = (mip_map_[level].data != nullptr);

                if (min_length < MipMapScaleFactor) {
                        // Search individual samples up to the beginning of
                        // the next first level mip map block
                        const uint64_t final_index = min(end, pow2_ceil(index, MipMapScalePower));

                        for (; index < final_index &&
                                        (index & ~((uint64_t)(~0) << MipMapScalePower)) != 0;
                                        index++) {

                                const bool sample = (get_unpacked_sample(index) & sig_mask) != 0;

                                // If there was a change we cannot fast forward
                                if (sample != last_sample) {
                                        fast_forward = false;
                                        break;
                                }
                        }
                } else {
                        // If resolution is less than a mip map block,
                        // round up to the beginning of the mip-map block
                        // for this level of detail
                        const int min_level_scale_power = (level + 1) * MipMapScalePower;
                        index = pow2_ceil(index, min_level_scale_power);
                        if (index >= end)
                                break;

                        // We can fast forward only if there was no change
                        const bool sample = (get_unpacked_sample(index) & sig_mask) != 0;
                        if (last_sample != sample)
                                fast_forward = false;
                }

                if (fast_forward) {

                        // Fast forward: This involves zooming out to higher
                        // levels of the mip map searching for changes, then
                        // zooming in on them to find the point where the edge
                        // begins.

                        // Slide right and zoom out at the beginnings of mip-map
                        // blocks until we encounter a change
                        while (true) {
                                const int level_scale_power = (level + 1) * MipMapScalePower;
                                const uint64_t offset = index >> level_scale_power;

                                // Check if we reached the last block at this
                                // level, or if there was a change in this block
                                if (offset >= mip_map_[level].length ||
                                        (get_subsample(level, offset) & sig_mask))
                                        break;

                                if ((offset & ~((uint64_t)(~0) << MipMapScalePower)) == 0) {
                                        // If we are now at the beginning of a
                                        // higher level mip-map block ascend one
                                        // level
                                        if ((level + 1 >= ScaleStepCount) || (!mip_map_[level + 1].data))
                                                break;

                                        level++;
                                } else {
                                        // Slide right to the beginning of the
                                        // next mip map block
                                        index = pow2_ceil(index + 1, level_scale_power);
                                }
                        }

                        // Zoom in, and slide right until we encounter a change,
                        // and repeat until we reach min_level
                        while (true) {
                                assert(mip_map_[level].data);

                                const int level_scale_power = (level + 1) * MipMapScalePower;
                                const uint64_t offset = index >> level_scale_power;

                                // Check if we reached the last block at this
                                // level, or if there was a change in this block
                                if (offset >= mip_map_[level].length ||
                                                (get_subsample(level, offset) & sig_mask)) {
                                        // Zoom in unless we reached the minimum
                                        // zoom
                                        if (level == min_level)
                                                break;

                                        level--;
                                } else {
                                        // Slide right to the beginning of the
                                        // next mip map block
                                        index = pow2_ceil(index + 1, level_scale_power);
                                }
                        }

                        // If individual samples within the limit of resolution,
                        // do a linear search for the next transition within the
                        // block
                        if (min_length < MipMapScaleFactor) {
                                for (; index < end; index++) {
                                        const bool sample = (get_unpacked_sample(index) & sig_mask) != 0;
                                        if (sample != last_sample)
                                                break;
                                }
                        }
                }

                //----- Store the edge -----//

                // Take the last sample of the quanization block
                const int64_t final_index = index + block_length;
                if (index + block_length > end)
                        break;

                // Store the final state
                const bool final_sample = (get_unpacked_sample(final_index - 1) & sig_mask) != 0;
                edges.emplace_back(index, final_sample);

                index = final_index;
                last_sample = final_sample;

                if (first_change_only)
                        break;
        }

        // Add the final state
        if (!first_change_only) {
                const bool end_sample = get_unpacked_sample(end) & sig_mask;
                if (last_sample != end_sample)
                        edges.emplace_back(end, end_sample);
                edges.emplace_back(end + 1, end_sample);
        }
}

void LogicSegment::get_surrounding_edges(vector<EdgePair> &dest,
        uint64_t origin_sample, float min_length, int sig_index)
{
        if (origin_sample >= sample_count_)
                return;

        // Put the edges vector on the heap, it can become quite big until we can
        // use a get_subsampled_edges() implementation that searches backwards
        vector<EdgePair>* edges = new vector<EdgePair>;

        // Get all edges to the left of origin_sample
        get_subsampled_edges(*edges, 0, origin_sample, min_length, sig_index, false);

        // If we don't specify "first only", the first and last edge are the states
        // at samples 0 and origin_sample. If only those exist, there are no edges
        if (edges->size() == 2) {
                delete edges;
                return;
        }

        // Dismiss the entry for origin_sample so that back() gives us the
        // real last entry
        edges->pop_back();
        dest.push_back(edges->back());
        edges->clear();

        // Get first edge to the right of origin_sample
        get_subsampled_edges(*edges, origin_sample, sample_count_, min_length, sig_index, true);

        // "first only" is specified, so nothing needs to be dismissed
        if (edges->size() == 0) {
                delete edges;
                return;
        }

        dest.push_back(edges->front());

        delete edges;
}

void LogicSegment::reallocate_mipmap_level(MipMapLevel &m)
{
        lock_guard<recursive_mutex> lock(mutex_);

        const uint64_t new_data_length = ((m.length + MipMapDataUnit - 1) /
                MipMapDataUnit) * MipMapDataUnit;

        if (new_data_length > m.data_length) {
                m.data_length = new_data_length;

                // Padding is added to allow for the uint64_t write word
                m.data = realloc(m.data, new_data_length * unit_size_ +
                        sizeof(uint64_t));
        }
}

void LogicSegment::append_payload_to_mipmap()
{
        MipMapLevel &m0 = mip_map_[0];
        uint64_t prev_length;
        uint8_t *dest_ptr;
        SegmentDataIterator* it;
        uint64_t accumulator;
        unsigned int diff_counter;

        // Expand the data buffer to fit the new samples
        prev_length = m0.length;
        m0.length = sample_count_ / MipMapScaleFactor;

        // Break off if there are no new samples to compute
        if (m0.length == prev_length)
                return;

        reallocate_mipmap_level(m0);

        dest_ptr = (uint8_t*)m0.data + prev_length * unit_size_;

        // Iterate through the samples to populate the first level mipmap
        const uint64_t start_sample = prev_length * MipMapScaleFactor;
        const uint64_t end_sample = m0.length * MipMapScaleFactor;
        uint64_t len_sample = end_sample - start_sample;
        it = begin_sample_iteration(start_sample);
        while (len_sample > 0) {
                // Number of samples available in this chunk
                uint64_t count = get_iterator_valid_length(it);
                // Reduce if less than asked for
                count = std::min(count, len_sample);
                uint8_t *src_ptr = get_iterator_value(it);
                // Submit these contiguous samples to downsampling in bulk
                if (unit_size_ == 1)
                        downsampleT<uint8_t>(src_ptr, dest_ptr, count);
                else if (unit_size_ == 2)
                        downsampleT<uint16_t>(src_ptr, dest_ptr, count);
                else if (unit_size_ == 4)
                        downsampleT<uint32_t>(src_ptr, dest_ptr, count);
                else if (unit_size_ == 8)
                        downsampleT<uint64_t>(src_ptr, dest_ptr, count);
                else
                        downsampleGeneric(src_ptr, dest_ptr, count);
                len_sample -= count;
                // Advance iterator, should move to start of next chunk
                continue_sample_iteration(it, count);
        }
        end_sample_iteration(it);

        // Compute higher level mipmaps
        for (unsigned int level = 1; level < ScaleStepCount; level++) {
                MipMapLevel &m = mip_map_[level];
                const MipMapLevel &ml = mip_map_[level - 1];

                // Expand the data buffer to fit the new samples
                prev_length = m.length;
                m.length = ml.length / MipMapScaleFactor;

                // Break off if there are no more samples to be computed
                if (m.length == prev_length)
                        break;

                reallocate_mipmap_level(m);

                // Subsample the lower level
                const uint8_t* src_ptr = (uint8_t*)ml.data +
                        unit_size_ * prev_length * MipMapScaleFactor;
                const uint8_t *const end_dest_ptr =
                        (uint8_t*)m.data + unit_size_ * m.length;

                for (dest_ptr = (uint8_t*)m.data +
                                unit_size_ * prev_length;
                                dest_ptr < end_dest_ptr;
                                dest_ptr += unit_size_) {
                        accumulator = 0;
                        diff_counter = MipMapScaleFactor;
                        while (diff_counter-- > 0) {
                                accumulator |= unpack_sample(src_ptr);
                                src_ptr += unit_size_;
                        }

                        pack_sample(dest_ptr, accumulator);
                }
        }
}

uint64_t LogicSegment::get_unpacked_sample(uint64_t index) const
{
        assert(index < sample_count_);

        assert(unit_size_ <= 8);  // 8 * 8 = 64 channels
        uint8_t data[8];

        get_raw_samples(index, 1, data);

        return unpack_sample(data);
}

uint64_t LogicSegment::get_subsample(int level, uint64_t offset) const
{
        assert(level >= 0);
        assert(mip_map_[level].data);
        return unpack_sample((uint8_t*)mip_map_[level].data +
                unit_size_ * offset);
}

uint64_t LogicSegment::pow2_ceil(uint64_t x, unsigned int power)
{
        const uint64_t p = UINT64_C(1) << power;
        return (x + p - 1) / p * p;
}

} // namespace data
} // namespace pv