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 void LogicSegment::get_subsampled_edges(
 188         vector<EdgePair> &edges,
 189         uint64_t start, uint64_t end,
 190         float min_length, int sig_index, bool first_change_only)
 191 {
 192         uint64_t index = start;
 193         unsigned int level;
 194         bool last_sample;
 195         bool fast_forward;
 196
 197         assert(start <= end);
 198         assert(min_length > 0);
 199         assert(sig_index >= 0);
 200         assert(sig_index < 64);
 201
 202         lock_guard<recursive_mutex> lock(mutex_);
 203
 204         // Make sure we only process as many samples as we have
 205         if (end > get_sample_count())
 206                 end = get_sample_count();
 207
 208         const uint64_t block_length = (uint64_t)max(min_length, 1.0f);
 209         const unsigned int min_level = max((int)floorf(logf(min_length) /
 210                 LogMipMapScaleFactor) - 1, 0);
 211         const uint64_t sig_mask = 1ULL << sig_index;
 212
 213         // Store the initial state
 214         last_sample = (get_unpacked_sample(start) & sig_mask) != 0;
 215         if (!first_change_only)
 216                 edges.emplace_back(index++, last_sample);
 217
 218         while (index + block_length <= end) {
 219                 //----- Continue to search -----//
 220                 level = min_level;
 221
 222                 // We cannot fast-forward if there is no mip-map data at
 223                 // the minimum level.
 224                 fast_forward = (mip_map_[level].data != nullptr);
 225
 226                 if (min_length < MipMapScaleFactor) {
 227                         // Search individual samples up to the beginning of
 228                         // the next first level mip map block
 229                         const uint64_t final_index = min(end, pow2_ceil(index, MipMapScalePower));
 230
 231                         for (; index < final_index &&
 232                                         (index & ~((uint64_t)(~0) << MipMapScalePower)) != 0;
 233                                         index++) {
 234
 235                                 const bool sample = (get_unpacked_sample(index) & sig_mask) != 0;
 236
 237                                 // If there was a change we cannot fast forward
 238                                 if (sample != last_sample) {
 239                                         fast_forward = false;
 240                                         break;
 241                                 }
 242                         }
 243                 } else {
 244                         // If resolution is less than a mip map block,
 245                         // round up to the beginning of the mip-map block
 246                         // for this level of detail
 247                         const int min_level_scale_power = (level + 1) * MipMapScalePower;
 248                         index = pow2_ceil(index, min_level_scale_power);
 249                         if (index >= end)
 250                                 break;
 251
 252                         // We can fast forward only if there was no change
 253                         const bool sample = (get_unpacked_sample(index) & sig_mask) != 0;
 254                         if (last_sample != sample)
 255                                 fast_forward = false;
 256                 }
 257
 258                 if (fast_forward) {
 259
 260                         // Fast forward: This involves zooming out to higher
 261                         // levels of the mip map searching for changes, then
 262                         // zooming in on them to find the point where the edge
 263                         // begins.
 264
 265                         // Slide right and zoom out at the beginnings of mip-map
 266                         // blocks until we encounter a change
 267                         while (true) {
 268                                 const int level_scale_power = (level + 1) * MipMapScalePower;
 269                                 const uint64_t offset = index >> level_scale_power;
 270
 271                                 // Check if we reached the last block at this
 272                                 // level, or if there was a change in this block
 273                                 if (offset >= mip_map_[level].length ||
 274                                         (get_subsample(level, offset) & sig_mask))
 275                                         break;
 276
 277                                 if ((offset & ~((uint64_t)(~0) << MipMapScalePower)) == 0) {
 278                                         // If we are now at the beginning of a
 279                                         // higher level mip-map block ascend one
 280                                         // level
 281                                         if ((level + 1 >= ScaleStepCount) || (!mip_map_[level + 1].data))
 282                                                 break;
 283
 284                                         level++;
 285                                 } else {
 286                                         // Slide right to the beginning of the
 287                                         // next mip map block
 288                                         index = pow2_ceil(index + 1, level_scale_power);
 289                                 }
 290                         }
 291
 292                         // Zoom in, and slide right until we encounter a change,
 293                         // and repeat until we reach min_level
 294                         while (true) {
 295                                 assert(mip_map_[level].data);
 296
 297                                 const int level_scale_power = (level + 1) * MipMapScalePower;
 298                                 const uint64_t offset = index >> level_scale_power;
 299
 300                                 // Check if we reached the last block at this
 301                                 // level, or if there was a change in this block
 302                                 if (offset >= mip_map_[level].length ||
 303                                                 (get_subsample(level, offset) & sig_mask)) {
 304                                         // Zoom in unless we reached the minimum
 305                                         // zoom
 306                                         if (level == min_level)
 307                                                 break;
 308
 309                                         level--;
 310                                 } else {
 311                                         // Slide right to the beginning of the
 312                                         // next mip map block
 313                                         index = pow2_ceil(index + 1, level_scale_power);
 314                                 }
 315                         }
 316
 317                         // If individual samples within the limit of resolution,
 318                         // do a linear search for the next transition within the
 319                         // block
 320                         if (min_length < MipMapScaleFactor) {
 321                                 for (; index < end; index++) {
 322                                         const bool sample = (get_unpacked_sample(index) & sig_mask) != 0;
 323                                         if (sample != last_sample)
 324                                                 break;
 325                                 }
 326                         }
 327                 }
 328
 329                 //----- Store the edge -----//
 330
 331                 // Take the last sample of the quanization block
 332                 const int64_t final_index = index + block_length;
 333                 if (index + block_length > end)
 334                         break;
 335
 336                 // Store the final state
 337                 const bool final_sample = (get_unpacked_sample(final_index - 1) & sig_mask) != 0;
 338                 edges.emplace_back(index, final_sample);
 339
 340                 index = final_index;
 341                 last_sample = final_sample;
 342
 343                 if (first_change_only)
 344                         break;
 345         }
 346
 347         // Add the final state
 348         if (!first_change_only) {
 349                 const bool end_sample = get_unpacked_sample(end) & sig_mask;
 350                 if (last_sample != end_sample)
 351                         edges.emplace_back(end, end_sample);
 352                 edges.emplace_back(end + 1, end_sample);
 353         }
 354 }
 355
 356 void LogicSegment::get_surrounding_edges(vector<EdgePair> &dest,
 357         uint64_t origin_sample, float min_length, int sig_index)
 358 {
 359         if (origin_sample >= sample_count_)
 360                 return;
 361
 362         // Put the edges vector on the heap, it can become quite big until we can
 363         // use a get_subsampled_edges() implementation that searches backwards
 364         vector<EdgePair>* edges = new vector<EdgePair>;
 365
 366         // Get all edges to the left of origin_sample
 367         get_subsampled_edges(*edges, 0, origin_sample, min_length, sig_index, false);
 368
 369         // If we don't specify "first only", the first and last edge are the states
 370         // at samples 0 and origin_sample. If only those exist, there are no edges
 371         if (edges->size() == 2) {
 372                 delete edges;
 373                 return;
 374         }
 375
 376         // Dismiss the entry for origin_sample so that back() gives us the
 377         // real last entry
 378         edges->pop_back();
 379         dest.push_back(edges->back());
 380         edges->clear();
 381
 382         // Get first edge to the right of origin_sample
 383         get_subsampled_edges(*edges, origin_sample, sample_count_, min_length, sig_index, true);
 384
 385         // "first only" is specified, so nothing needs to be dismissed
 386         if (edges->size() == 0) {
 387                 delete edges;
 388                 return;
 389         }
 390
 391         dest.push_back(edges->front());
 392
 393         delete edges;
 394 }
 395
 396 void LogicSegment::reallocate_mipmap_level(MipMapLevel &m)
 397 {
 398         lock_guard<recursive_mutex> lock(mutex_);
 399
 400         const uint64_t new_data_length = ((m.length + MipMapDataUnit - 1) /
 401                 MipMapDataUnit) * MipMapDataUnit;
 402
 403         if (new_data_length > m.data_length) {
 404                 m.data_length = new_data_length;
 405
 406                 // Padding is added to allow for the uint64_t write word
 407                 m.data = realloc(m.data, new_data_length * unit_size_ +
 408                         sizeof(uint64_t));
 409         }
 410 }
 411
 412 void LogicSegment::append_payload_to_mipmap()
 413 {
 414         MipMapLevel &m0 = mip_map_[0];
 415         uint64_t prev_length;
 416         uint8_t *dest_ptr;
 417         SegmentDataIterator* it;
 418         uint64_t accumulator;
 419         unsigned int diff_counter;
 420
 421         // Expand the data buffer to fit the new samples
 422         prev_length = m0.length;
 423         m0.length = sample_count_ / MipMapScaleFactor;
 424
 425         // Break off if there are no new samples to compute
 426         if (m0.length == prev_length)
 427                 return;
 428
 429         reallocate_mipmap_level(m0);
 430
 431         dest_ptr = (uint8_t*)m0.data + prev_length * unit_size_;
 432
 433         // Iterate through the samples to populate the first level mipmap
 434         const uint64_t start_sample = prev_length * MipMapScaleFactor;
 435         const uint64_t end_sample = m0.length * MipMapScaleFactor;
 436
 437         it = begin_sample_iteration(start_sample);
 438         for (uint64_t i = start_sample; i < end_sample;) {
 439                 // Accumulate transitions which have occurred in this sample
 440                 accumulator = 0;
 441                 diff_counter = MipMapScaleFactor;
 442                 while (diff_counter-- > 0) {
 443                         const uint64_t sample = unpack_sample(get_iterator_value(it));
 444                         accumulator |= last_append_sample_ ^ sample;
 445                         last_append_sample_ = sample;
 446                         continue_sample_iteration(it, 1);
 447                         i++;
 448                 }
 449
 450                 pack_sample(dest_ptr, accumulator);
 451                 dest_ptr += unit_size_;
 452         }
 453         end_sample_iteration(it);
 454
 455         // Compute higher level mipmaps
 456         for (unsigned int level = 1; level < ScaleStepCount; level++) {
 457                 MipMapLevel &m = mip_map_[level];
 458                 const MipMapLevel &ml = mip_map_[level - 1];
 459
 460                 // Expand the data buffer to fit the new samples
 461                 prev_length = m.length;
 462                 m.length = ml.length / MipMapScaleFactor;
 463
 464                 // Break off if there are no more samples to be computed
 465                 if (m.length == prev_length)
 466                         break;
 467
 468                 reallocate_mipmap_level(m);
 469
 470                 // Subsample the lower level
 471                 const uint8_t* src_ptr = (uint8_t*)ml.data +
 472                         unit_size_ * prev_length * MipMapScaleFactor;
 473                 const uint8_t *const end_dest_ptr =
 474                         (uint8_t*)m.data + unit_size_ * m.length;
 475
 476                 for (dest_ptr = (uint8_t*)m.data +
 477                                 unit_size_ * prev_length;
 478                                 dest_ptr < end_dest_ptr;
 479                                 dest_ptr += unit_size_) {
 480                         accumulator = 0;
 481                         diff_counter = MipMapScaleFactor;
 482                         while (diff_counter-- > 0) {
 483                                 accumulator |= unpack_sample(src_ptr);
 484                                 src_ptr += unit_size_;
 485                         }
 486
 487                         pack_sample(dest_ptr, accumulator);
 488                 }
 489         }
 490 }
 491
 492 uint64_t LogicSegment::get_unpacked_sample(uint64_t index) const
 493 {
 494         assert(index < sample_count_);
 495
 496         assert(unit_size_ <= 8);  // 8 * 8 = 64 channels
 497         uint8_t data[8];
 498
 499         get_raw_samples(index, 1, data);
 500
 501         return unpack_sample(data);
 502 }
 503
 504 uint64_t LogicSegment::get_subsample(int level, uint64_t offset) const
 505 {
 506         assert(level >= 0);
 507         assert(mip_map_[level].data);
 508         return unpack_sample((uint8_t*)mip_map_[level].data +
 509                 unit_size_ * offset);
 510 }
 511
 512 uint64_t LogicSegment::pow2_ceil(uint64_t x, unsigned int power)
 513 {
 514         const uint64_t p = UINT64_C(1) << power;
 515         return (x + p - 1) / p * p;
 516 }
 517
 518 } // namespace data
 519 } // namespace pv