pv/data/logicsegment.cpp

   1 /*
   2  * This file is part of the PulseView project.
   3  *
   4  * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "config.h" // For HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
  21
  22 #include <extdef.h>
  23
  24 #include <cassert>
  25 #include <cmath>
  26 #include <cstdlib>
  27 #include <cstring>
  28 #include <cstdint>
  29
  30 #include "logic.hpp"
  31 #include "logicsegment.hpp"
  32
  33 #include <libsigrokcxx/libsigrokcxx.hpp>
  34
  35 using std::lock_guard;
  36 using std::recursive_mutex;
  37 using std::max;
  38 using std::min;
  39 using std::shared_ptr;
  40 using std::vector;
  41
  42 using sigrok::Logic;
  43
  44 namespace pv {
  45 namespace data {
  46
  47 const int LogicSegment::MipMapScalePower = 4;
  48 const int LogicSegment::MipMapScaleFactor = 1 << MipMapScalePower;
  49 const float LogicSegment::LogMipMapScaleFactor = logf(MipMapScaleFactor);
  50 const uint64_t LogicSegment::MipMapDataUnit = 64 * 1024; // bytes
  51
  52 LogicSegment::LogicSegment(pv::data::Logic& owner, uint32_t segment_id,
  53         unsigned int unit_size, uint64_t samplerate) :
  54         Segment(segment_id, samplerate, unit_size),
  55         owner_(owner),
  56         last_append_sample_(0)
  57 {
  58         memset(mip_map_, 0, sizeof(mip_map_));
  59 }
  60
  61 LogicSegment::~LogicSegment()
  62 {
  63         lock_guard<recursive_mutex> lock(mutex_);
  64         for (MipMapLevel &l : mip_map_)
  65                 free(l.data);
  66 }
  67
  68 inline uint64_t LogicSegment::unpack_sample(const uint8_t *ptr) const
  69 {
  70 #ifdef HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
  71         return *(uint64_t*)ptr;
  72 #else
  73         uint64_t value = 0;
  74         switch (unit_size_) {
  75         default:
  76                 value |= ((uint64_t)ptr[7]) << 56;
  77                 /* FALLTHRU */
  78         case 7:
  79                 value |= ((uint64_t)ptr[6]) << 48;
  80                 /* FALLTHRU */
  81         case 6:
  82                 value |= ((uint64_t)ptr[5]) << 40;
  83                 /* FALLTHRU */
  84         case 5:
  85                 value |= ((uint64_t)ptr[4]) << 32;
  86                 /* FALLTHRU */
  87         case 4:
  88                 value |= ((uint32_t)ptr[3]) << 24;
  89                 /* FALLTHRU */
  90         case 3:
  91                 value |= ((uint32_t)ptr[2]) << 16;
  92                 /* FALLTHRU */
  93         case 2:
  94                 value |= ptr[1] << 8;
  95                 /* FALLTHRU */
  96         case 1:
  97                 value |= ptr[0];
  98                 /* FALLTHRU */
  99         case 0:
 100                 break;
 101         }
 102         return value;
 103 #endif
 104 }
 105
 106 inline void LogicSegment::pack_sample(uint8_t *ptr, uint64_t value)
 107 {
 108 #ifdef HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
 109         *(uint64_t*)ptr = value;
 110 #else
 111         switch (unit_size_) {
 112         default:
 113                 ptr[7] = value >> 56;
 114                 /* FALLTHRU */
 115         case 7:
 116                 ptr[6] = value >> 48;
 117                 /* FALLTHRU */
 118         case 6:
 119                 ptr[5] = value >> 40;
 120                 /* FALLTHRU */
 121         case 5:
 122                 ptr[4] = value >> 32;
 123                 /* FALLTHRU */
 124         case 4:
 125                 ptr[3] = value >> 24;
 126                 /* FALLTHRU */
 127         case 3:
 128                 ptr[2] = value >> 16;
 129                 /* FALLTHRU */
 130         case 2:
 131                 ptr[1] = value >> 8;
 132                 /* FALLTHRU */
 133         case 1:
 134                 ptr[0] = value;
 135                 /* FALLTHRU */
 136         case 0:
 137                 break;
 138         }
 139 #endif
 140 }
 141
 142 void LogicSegment::append_payload(shared_ptr<sigrok::Logic> logic)
 143 {
 144         assert(unit_size_ == logic->unit_size());
 145         assert((logic->data_length() % unit_size_) == 0);
 146
 147         append_payload(logic->data_pointer(), logic->data_length());
 148 }
 149
 150 void LogicSegment::append_payload(void *data, uint64_t data_size)
 151 {
 152         assert((data_size % unit_size_) == 0);
 153
 154         lock_guard<recursive_mutex> lock(mutex_);
 155
 156         const uint64_t prev_sample_count = sample_count_;
 157         const uint64_t sample_count = data_size / unit_size_;
 158
 159         append_samples(data, sample_count);
 160
 161         // Generate the first mip-map from the data
 162         append_payload_to_mipmap();
 163
 164         if (sample_count > 1)
 165                 owner_.notify_samples_added(this, prev_sample_count + 1,
 166                         prev_sample_count + 1 + sample_count);
 167         else
 168                 owner_.notify_samples_added(this, prev_sample_count + 1,
 169                         prev_sample_count + 1);
 170 }
 171
 172 void LogicSegment::get_samples(int64_t start_sample,
 173         int64_t end_sample,     uint8_t* dest) const
 174 {
 175         assert(start_sample >= 0);
 176         assert(start_sample <= (int64_t)sample_count_);
 177         assert(end_sample >= 0);
 178         assert(end_sample <= (int64_t)sample_count_);
 179         assert(start_sample <= end_sample);
 180         assert(dest != nullptr);
 181
 182         lock_guard<recursive_mutex> lock(mutex_);
 183
 184         get_raw_samples(start_sample, (end_sample - start_sample), dest);
 185 }
 186
 187 SegmentLogicDataIterator* LogicSegment::begin_sample_iteration(uint64_t start)
 188 {
 189         return (SegmentLogicDataIterator*)begin_raw_sample_iteration(start);
 190 }
 191
 192 void LogicSegment::continue_sample_iteration(SegmentLogicDataIterator* it, uint64_t increase)
 193 {
 194         Segment::continue_raw_sample_iteration((SegmentRawDataIterator*)it, increase);
 195 }
 196
 197 void LogicSegment::end_sample_iteration(SegmentLogicDataIterator* it)
 198 {
 199         Segment::end_raw_sample_iteration((SegmentRawDataIterator*)it);
 200 }
 201
 202 void LogicSegment::get_subsampled_edges(
 203         vector<EdgePair> &edges,
 204         uint64_t start, uint64_t end,
 205         float min_length, int sig_index, bool first_change_only)
 206 {
 207         uint64_t index = start;
 208         unsigned int level;
 209         bool last_sample;
 210         bool fast_forward;
 211
 212         assert(start <= end);
 213         assert(min_length > 0);
 214         assert(sig_index >= 0);
 215         assert(sig_index < 64);
 216
 217         lock_guard<recursive_mutex> lock(mutex_);
 218
 219         // Make sure we only process as many samples as we have
 220         if (end > get_sample_count())
 221                 end = get_sample_count();
 222
 223         const uint64_t block_length = (uint64_t)max(min_length, 1.0f);
 224         const unsigned int min_level = max((int)floorf(logf(min_length) /
 225                 LogMipMapScaleFactor) - 1, 0);
 226         const uint64_t sig_mask = 1ULL << sig_index;
 227
 228         // Store the initial state
 229         last_sample = (get_unpacked_sample(start) & sig_mask) != 0;
 230         if (!first_change_only)
 231                 edges.emplace_back(index++, last_sample);
 232
 233         while (index + block_length <= end) {
 234                 //----- Continue to search -----//
 235                 level = min_level;
 236
 237                 // We cannot fast-forward if there is no mip-map data at
 238                 // the minimum level.
 239                 fast_forward = (mip_map_[level].data != nullptr);
 240
 241                 if (min_length < MipMapScaleFactor) {
 242                         // Search individual samples up to the beginning of
 243                         // the next first level mip map block
 244                         const uint64_t final_index = min(end, pow2_ceil(index, MipMapScalePower));
 245
 246                         for (; index < final_index &&
 247                                         (index & ~((uint64_t)(~0) << MipMapScalePower)) != 0;
 248                                         index++) {
 249
 250                                 const bool sample = (get_unpacked_sample(index) & sig_mask) != 0;
 251
 252                                 // If there was a change we cannot fast forward
 253                                 if (sample != last_sample) {
 254                                         fast_forward = false;
 255                                         break;
 256                                 }
 257                         }
 258                 } else {
 259                         // If resolution is less than a mip map block,
 260                         // round up to the beginning of the mip-map block
 261                         // for this level of detail
 262                         const int min_level_scale_power = (level + 1) * MipMapScalePower;
 263                         index = pow2_ceil(index, min_level_scale_power);
 264                         if (index >= end)
 265                                 break;
 266
 267                         // We can fast forward only if there was no change
 268                         const bool sample = (get_unpacked_sample(index) & sig_mask) != 0;
 269                         if (last_sample != sample)
 270                                 fast_forward = false;
 271                 }
 272
 273                 if (fast_forward) {
 274
 275                         // Fast forward: This involves zooming out to higher
 276                         // levels of the mip map searching for changes, then
 277                         // zooming in on them to find the point where the edge
 278                         // begins.
 279
 280                         // Slide right and zoom out at the beginnings of mip-map
 281                         // blocks until we encounter a change
 282                         while (true) {
 283                                 const int level_scale_power = (level + 1) * MipMapScalePower;
 284                                 const uint64_t offset = index >> level_scale_power;
 285
 286                                 // Check if we reached the last block at this
 287                                 // level, or if there was a change in this block
 288                                 if (offset >= mip_map_[level].length ||
 289                                         (get_subsample(level, offset) & sig_mask))
 290                                         break;
 291
 292                                 if ((offset & ~((uint64_t)(~0) << MipMapScalePower)) == 0) {
 293                                         // If we are now at the beginning of a
 294                                         // higher level mip-map block ascend one
 295                                         // level
 296                                         if ((level + 1 >= ScaleStepCount) || (!mip_map_[level + 1].data))
 297                                                 break;
 298
 299                                         level++;
 300                                 } else {
 301                                         // Slide right to the beginning of the
 302                                         // next mip map block
 303                                         index = pow2_ceil(index + 1, level_scale_power);
 304                                 }
 305                         }
 306
 307                         // Zoom in, and slide right until we encounter a change,
 308                         // and repeat until we reach min_level
 309                         while (true) {
 310                                 assert(mip_map_[level].data);
 311
 312                                 const int level_scale_power = (level + 1) * MipMapScalePower;
 313                                 const uint64_t offset = index >> level_scale_power;
 314
 315                                 // Check if we reached the last block at this
 316                                 // level, or if there was a change in this block
 317                                 if (offset >= mip_map_[level].length ||
 318                                                 (get_subsample(level, offset) & sig_mask)) {
 319                                         // Zoom in unless we reached the minimum
 320                                         // zoom
 321                                         if (level == min_level)
 322                                                 break;
 323
 324                                         level--;
 325                                 } else {
 326                                         // Slide right to the beginning of the
 327                                         // next mip map block
 328                                         index = pow2_ceil(index + 1, level_scale_power);
 329                                 }
 330                         }
 331
 332                         // If individual samples within the limit of resolution,
 333                         // do a linear search for the next transition within the
 334                         // block
 335                         if (min_length < MipMapScaleFactor) {
 336                                 for (; index < end; index++) {
 337                                         const bool sample = (get_unpacked_sample(index) & sig_mask) != 0;
 338                                         if (sample != last_sample)
 339                                                 break;
 340                                 }
 341                         }
 342                 }
 343
 344                 //----- Store the edge -----//
 345
 346                 // Take the last sample of the quanization block
 347                 const int64_t final_index = index + block_length;
 348                 if (index + block_length > end)
 349                         break;
 350
 351                 // Store the final state
 352                 const bool final_sample = (get_unpacked_sample(final_index - 1) & sig_mask) != 0;
 353                 edges.emplace_back(index, final_sample);
 354
 355                 index = final_index;
 356                 last_sample = final_sample;
 357
 358                 if (first_change_only)
 359                         break;
 360         }
 361
 362         // Add the final state
 363         if (!first_change_only) {
 364                 const bool end_sample = get_unpacked_sample(end) & sig_mask;
 365                 if (last_sample != end_sample)
 366                         edges.emplace_back(end, end_sample);
 367                 edges.emplace_back(end + 1, end_sample);
 368         }
 369 }
 370
 371 void LogicSegment::get_surrounding_edges(vector<EdgePair> &dest,
 372         uint64_t origin_sample, float min_length, int sig_index)
 373 {
 374         // Put the edges vector on the heap, it can become quite big until we can
 375         // use a get_subsampled_edges() implementation that searches backwards
 376         vector<EdgePair>* edges = new vector<EdgePair>;
 377
 378         get_subsampled_edges(*edges, 0, origin_sample, min_length, sig_index, false);
 379
 380         // If we don't specify "first only", the first and last edge are the states
 381         // at samples 0 and origin_sample. If only those exist, there are no edges
 382         if (edges->size() == 2) {
 383                 delete edges;
 384                 return;
 385         }
 386
 387         // Dismiss the entry for origin_sample so that back() gives us the
 388         // real last entry
 389         edges->pop_back();
 390         dest.push_back(edges->back());
 391         edges->clear();
 392
 393         get_subsampled_edges(*edges, origin_sample, sample_count_, min_length, sig_index, true);
 394
 395         // "first only" is specified, so nothing needs to be dismissed
 396         if (edges->size() == 0) {
 397                 delete edges;
 398                 return;
 399         }
 400
 401         dest.push_back(edges->front());
 402
 403         delete edges;
 404 }
 405
 406 void LogicSegment::reallocate_mipmap_level(MipMapLevel &m)
 407 {
 408         lock_guard<recursive_mutex> lock(mutex_);
 409
 410         const uint64_t new_data_length = ((m.length + MipMapDataUnit - 1) /
 411                 MipMapDataUnit) * MipMapDataUnit;
 412
 413         if (new_data_length > m.data_length) {
 414                 m.data_length = new_data_length;
 415
 416                 // Padding is added to allow for the uint64_t write word
 417                 m.data = realloc(m.data, new_data_length * unit_size_ +
 418                         sizeof(uint64_t));
 419         }
 420 }
 421
 422 void LogicSegment::append_payload_to_mipmap()
 423 {
 424         MipMapLevel &m0 = mip_map_[0];
 425         uint64_t prev_length;
 426         uint8_t *dest_ptr;
 427         SegmentRawDataIterator* it;
 428         uint64_t accumulator;
 429         unsigned int diff_counter;
 430
 431         // Expand the data buffer to fit the new samples
 432         prev_length = m0.length;
 433         m0.length = sample_count_ / MipMapScaleFactor;
 434
 435         // Break off if there are no new samples to compute
 436         if (m0.length == prev_length)
 437                 return;
 438
 439         reallocate_mipmap_level(m0);
 440
 441         dest_ptr = (uint8_t*)m0.data + prev_length * unit_size_;
 442
 443         // Iterate through the samples to populate the first level mipmap
 444         const uint64_t start_sample = prev_length * MipMapScaleFactor;
 445         const uint64_t end_sample = m0.length * MipMapScaleFactor;
 446
 447         it = begin_raw_sample_iteration(start_sample);
 448         for (uint64_t i = start_sample; i < end_sample;) {
 449                 // Accumulate transitions which have occurred in this sample
 450                 accumulator = 0;
 451                 diff_counter = MipMapScaleFactor;
 452                 while (diff_counter-- > 0) {
 453                         const uint64_t sample = unpack_sample(it->value);
 454                         accumulator |= last_append_sample_ ^ sample;
 455                         last_append_sample_ = sample;
 456                         continue_raw_sample_iteration(it, 1);
 457                         i++;
 458                 }
 459
 460                 pack_sample(dest_ptr, accumulator);
 461                 dest_ptr += unit_size_;
 462         }
 463         end_raw_sample_iteration(it);
 464
 465         // Compute higher level mipmaps
 466         for (unsigned int level = 1; level < ScaleStepCount; level++) {
 467                 MipMapLevel &m = mip_map_[level];
 468                 const MipMapLevel &ml = mip_map_[level - 1];
 469
 470                 // Expand the data buffer to fit the new samples
 471                 prev_length = m.length;
 472                 m.length = ml.length / MipMapScaleFactor;
 473
 474                 // Break off if there are no more samples to be computed
 475                 if (m.length == prev_length)
 476                         break;
 477
 478                 reallocate_mipmap_level(m);
 479
 480                 // Subsample the lower level
 481                 const uint8_t* src_ptr = (uint8_t*)ml.data +
 482                         unit_size_ * prev_length * MipMapScaleFactor;
 483                 const uint8_t *const end_dest_ptr =
 484                         (uint8_t*)m.data + unit_size_ * m.length;
 485
 486                 for (dest_ptr = (uint8_t*)m.data +
 487                                 unit_size_ * prev_length;
 488                                 dest_ptr < end_dest_ptr;
 489                                 dest_ptr += unit_size_) {
 490                         accumulator = 0;
 491                         diff_counter = MipMapScaleFactor;
 492                         while (diff_counter-- > 0) {
 493                                 accumulator |= unpack_sample(src_ptr);
 494                                 src_ptr += unit_size_;
 495                         }
 496
 497                         pack_sample(dest_ptr, accumulator);
 498                 }
 499         }
 500 }
 501
 502 uint64_t LogicSegment::get_unpacked_sample(uint64_t index) const
 503 {
 504         assert(index < sample_count_);
 505
 506         assert(unit_size_ <= 8);  // 8 * 8 = 64 channels
 507         uint8_t data[8];
 508
 509         get_raw_samples(index, 1, data);
 510
 511         return unpack_sample(data);
 512 }
 513
 514 uint64_t LogicSegment::get_subsample(int level, uint64_t offset) const
 515 {
 516         assert(level >= 0);
 517         assert(mip_map_[level].data);
 518         return unpack_sample((uint8_t*)mip_map_[level].data +
 519                 unit_size_ * offset);
 520 }
 521
 522 uint64_t LogicSegment::pow2_ceil(uint64_t x, unsigned int power)
 523 {
 524         const uint64_t p = UINT64_C(1) << power;
 525         return (x + p - 1) / p * p;
 526 }
 527
 528 } // namespace data
 529 } // namespace pv