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