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