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 <cmath>
  24 #include <cstdlib>
  25 #include <cstring>
  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::shared_ptr;
  37 using std::vector;
  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, unsigned int unit_size,
  50         uint64_t samplerate) :
  51         Segment(samplerate, unit_size),
  52         owner_(owner),
  53         last_append_sample_(0)
  54 {
  55         memset(mip_map_, 0, sizeof(mip_map_));
  56 }
  57
  58 LogicSegment::~LogicSegment()
  59 {
  60         lock_guard<recursive_mutex> lock(mutex_);
  61         for (MipMapLevel &l : mip_map_)
  62                 free(l.data);
  63 }
  64
  65 uint64_t LogicSegment::unpack_sample(const uint8_t *ptr) const
  66 {
  67 #ifdef HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
  68         return *(uint64_t*)ptr;
  69 #else
  70         uint64_t value = 0;
  71         switch (unit_size_) {
  72         default:
  73                 value |= ((uint64_t)ptr[7]) << 56;
  74                 /* FALLTHRU */
  75         case 7:
  76                 value |= ((uint64_t)ptr[6]) << 48;
  77                 /* FALLTHRU */
  78         case 6:
  79                 value |= ((uint64_t)ptr[5]) << 40;
  80                 /* FALLTHRU */
  81         case 5:
  82                 value |= ((uint64_t)ptr[4]) << 32;
  83                 /* FALLTHRU */
  84         case 4:
  85                 value |= ((uint32_t)ptr[3]) << 24;
  86                 /* FALLTHRU */
  87         case 3:
  88                 value |= ((uint32_t)ptr[2]) << 16;
  89                 /* FALLTHRU */
  90         case 2:
  91                 value |= ptr[1] << 8;
  92                 /* FALLTHRU */
  93         case 1:
  94                 value |= ptr[0];
  95                 /* FALLTHRU */
  96         case 0:
  97                 break;
  98         }
  99         return value;
 100 #endif
 101 }
 102
 103 void LogicSegment::pack_sample(uint8_t *ptr, uint64_t value)
 104 {
 105 #ifdef HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
 106         *(uint64_t*)ptr = value;
 107 #else
 108         switch (unit_size_) {
 109         default:
 110                 ptr[7] = value >> 56;
 111                 /* FALLTHRU */
 112         case 7:
 113                 ptr[6] = value >> 48;
 114                 /* FALLTHRU */
 115         case 6:
 116                 ptr[5] = value >> 40;
 117                 /* FALLTHRU */
 118         case 5:
 119                 ptr[4] = value >> 32;
 120                 /* FALLTHRU */
 121         case 4:
 122                 ptr[3] = value >> 24;
 123                 /* FALLTHRU */
 124         case 3:
 125                 ptr[2] = value >> 16;
 126                 /* FALLTHRU */
 127         case 2:
 128                 ptr[1] = value >> 8;
 129                 /* FALLTHRU */
 130         case 1:
 131                 ptr[0] = value;
 132                 /* FALLTHRU */
 133         case 0:
 134                 break;
 135         }
 136 #endif
 137 }
 138
 139 void LogicSegment::append_payload(shared_ptr<sigrok::Logic> logic)
 140 {
 141         assert(unit_size_ == logic->unit_size());
 142         assert((logic->data_length() % unit_size_) == 0);
 143
 144         append_payload(logic->data_pointer(), logic->data_length());
 145 }
 146
 147 void LogicSegment::append_payload(void *data, uint64_t data_size)
 148 {
 149         assert((data_size % unit_size_) == 0);
 150
 151         lock_guard<recursive_mutex> lock(mutex_);
 152
 153         uint64_t prev_sample_count = sample_count_;
 154         uint64_t sample_count = data_size / unit_size_;
 155
 156         append_samples(data, sample_count);
 157
 158         // Generate the first mip-map from the data
 159         append_payload_to_mipmap();
 160
 161         if (sample_count > 1)
 162                 owner_.notify_samples_added(this, prev_sample_count + 1,
 163                         prev_sample_count + 1 + sample_count);
 164         else
 165                 owner_.notify_samples_added(this, prev_sample_count + 1,
 166                         prev_sample_count + 1);
 167 }
 168
 169 const uint8_t* LogicSegment::get_samples(int64_t start_sample,
 170         int64_t end_sample) const
 171 {
 172         assert(start_sample >= 0);
 173         assert(start_sample <= (int64_t)sample_count_);
 174         assert(end_sample >= 0);
 175         assert(end_sample <= (int64_t)sample_count_);
 176         assert(start_sample <= end_sample);
 177
 178         lock_guard<recursive_mutex> lock(mutex_);
 179
 180         return get_raw_samples(start_sample, (end_sample - start_sample));
 181 }
 182
 183 SegmentLogicDataIterator* LogicSegment::begin_sample_iteration(uint64_t start)
 184 {
 185         return (SegmentLogicDataIterator*)begin_raw_sample_iteration(start);
 186 }
 187
 188 void LogicSegment::continue_sample_iteration(SegmentLogicDataIterator* it, uint64_t increase)
 189 {
 190         Segment::continue_raw_sample_iteration((SegmentRawDataIterator*)it, increase);
 191 }
 192
 193 void LogicSegment::end_sample_iteration(SegmentLogicDataIterator* it)
 194 {
 195         Segment::end_raw_sample_iteration((SegmentRawDataIterator*)it);
 196 }
 197
 198 void LogicSegment::reallocate_mipmap_level(MipMapLevel &m)
 199 {
 200         lock_guard<recursive_mutex> lock(mutex_);
 201
 202         const uint64_t new_data_length = ((m.length + MipMapDataUnit - 1) /
 203                 MipMapDataUnit) * MipMapDataUnit;
 204
 205         if (new_data_length > m.data_length) {
 206                 m.data_length = new_data_length;
 207
 208                 // Padding is added to allow for the uint64_t write word
 209                 m.data = realloc(m.data, new_data_length * unit_size_ +
 210                         sizeof(uint64_t));
 211         }
 212 }
 213
 214 void LogicSegment::append_payload_to_mipmap()
 215 {
 216         MipMapLevel &m0 = mip_map_[0];
 217         uint64_t prev_length;
 218         uint8_t *dest_ptr;
 219         SegmentRawDataIterator* it;
 220         uint64_t accumulator;
 221         unsigned int diff_counter;
 222
 223         // Expand the data buffer to fit the new samples
 224         prev_length = m0.length;
 225         m0.length = sample_count_ / MipMapScaleFactor;
 226
 227         // Break off if there are no new samples to compute
 228         if (m0.length == prev_length)
 229                 return;
 230
 231         reallocate_mipmap_level(m0);
 232
 233         dest_ptr = (uint8_t*)m0.data + prev_length * unit_size_;
 234
 235         // Iterate through the samples to populate the first level mipmap
 236         uint64_t start_sample = prev_length * MipMapScaleFactor;
 237         uint64_t end_sample = m0.length * MipMapScaleFactor;
 238
 239         it = begin_raw_sample_iteration(start_sample);
 240         for (uint64_t i = start_sample; i < end_sample;) {
 241                 // Accumulate transitions which have occurred in this sample
 242                 accumulator = 0;
 243                 diff_counter = MipMapScaleFactor;
 244                 while (diff_counter-- > 0) {
 245                         const uint64_t sample = unpack_sample(it->value);
 246                         accumulator |= last_append_sample_ ^ sample;
 247                         last_append_sample_ = sample;
 248                         continue_raw_sample_iteration(it, 1);
 249                         i++;
 250                 }
 251
 252                 pack_sample(dest_ptr, accumulator);
 253                 dest_ptr += unit_size_;
 254         }
 255         end_raw_sample_iteration(it);
 256
 257         // Compute higher level mipmaps
 258         for (unsigned int level = 1; level < ScaleStepCount; level++) {
 259                 MipMapLevel &m = mip_map_[level];
 260                 const MipMapLevel &ml = mip_map_[level - 1];
 261
 262                 // Expand the data buffer to fit the new samples
 263                 prev_length = m.length;
 264                 m.length = ml.length / MipMapScaleFactor;
 265
 266                 // Break off if there are no more samples to be computed
 267                 if (m.length == prev_length)
 268                         break;
 269
 270                 reallocate_mipmap_level(m);
 271
 272                 // Subsample the lower level
 273                 const uint8_t* src_ptr = (uint8_t*)ml.data +
 274                         unit_size_ * prev_length * MipMapScaleFactor;
 275                 const uint8_t *const end_dest_ptr =
 276                         (uint8_t*)m.data + unit_size_ * m.length;
 277
 278                 for (dest_ptr = (uint8_t*)m.data +
 279                                 unit_size_ * prev_length;
 280                                 dest_ptr < end_dest_ptr;
 281                                 dest_ptr += unit_size_) {
 282                         accumulator = 0;
 283                         diff_counter = MipMapScaleFactor;
 284                         while (diff_counter-- > 0) {
 285                                 accumulator |= unpack_sample(src_ptr);
 286                                 src_ptr += unit_size_;
 287                         }
 288
 289                         pack_sample(dest_ptr, accumulator);
 290                 }
 291         }
 292 }
 293
 294 uint64_t LogicSegment::get_unpacked_sample(uint64_t index) const
 295 {
 296         assert(index < sample_count_);
 297
 298         const uint8_t* data = get_raw_samples(index, 1);
 299         uint64_t sample = unpack_sample(data);
 300         delete[] data;
 301
 302         return sample;
 303 }
 304
 305 void LogicSegment::get_subsampled_edges(
 306         vector<EdgePair> &edges,
 307         uint64_t start, uint64_t end,
 308         float min_length, int sig_index)
 309 {
 310         uint64_t index = start;
 311         unsigned int level;
 312         bool last_sample;
 313         bool fast_forward;
 314
 315         assert(end <= get_sample_count());
 316         assert(start <= end);
 317         assert(min_length > 0);
 318         assert(sig_index >= 0);
 319         assert(sig_index < 64);
 320
 321         lock_guard<recursive_mutex> lock(mutex_);
 322
 323         const uint64_t block_length = (uint64_t)max(min_length, 1.0f);
 324         const unsigned int min_level = max((int)floorf(logf(min_length) /
 325                 LogMipMapScaleFactor) - 1, 0);
 326         const uint64_t sig_mask = 1ULL << sig_index;
 327
 328         // Store the initial state
 329         last_sample = (get_unpacked_sample(start) & sig_mask) != 0;
 330         edges.emplace_back(index++, last_sample);
 331
 332         while (index + block_length <= end) {
 333                 //----- Continue to search -----//
 334                 level = min_level;
 335
 336                 // We cannot fast-forward if there is no mip-map data at
 337                 // at the minimum level.
 338                 fast_forward = (mip_map_[level].data != nullptr);
 339
 340                 if (min_length < MipMapScaleFactor) {
 341                         // Search individual samples up to the beginning of
 342                         // the next first level mip map block
 343                         const uint64_t final_index = min(end,
 344                                 pow2_ceil(index, MipMapScalePower));
 345
 346                         for (; index < final_index &&
 347                                         (index & ~((uint64_t)(~0) << MipMapScalePower)) != 0;
 348                                         index++) {
 349                                 const bool sample =
 350                                         (get_unpacked_sample(index) & sig_mask) != 0;
 351
 352                                 // If there was a change we cannot fast forward
 353                                 if (sample != last_sample) {
 354                                         fast_forward = false;
 355                                         break;
 356                                 }
 357                         }
 358                 } else {
 359                         // If resolution is less than a mip map block,
 360                         // round up to the beginning of the mip-map block
 361                         // for this level of detail
 362                         const int min_level_scale_power =
 363                                 (level + 1) * MipMapScalePower;
 364                         index = pow2_ceil(index, min_level_scale_power);
 365                         if (index >= end)
 366                                 break;
 367
 368                         // We can fast forward only if there was no change
 369                         const bool sample =
 370                                 (get_unpacked_sample(index) & sig_mask) != 0;
 371                         if (last_sample != sample)
 372                                 fast_forward = false;
 373                 }
 374
 375                 if (fast_forward) {
 376
 377                         // Fast forward: This involves zooming out to higher
 378                         // levels of the mip map searching for changes, then
 379                         // zooming in on them to find the point where the edge
 380                         // begins.
 381
 382                         // Slide right and zoom out at the beginnings of mip-map
 383                         // blocks until we encounter a change
 384                         while (true) {
 385                                 const int level_scale_power =
 386                                         (level + 1) * MipMapScalePower;
 387                                 const uint64_t offset =
 388                                         index >> level_scale_power;
 389
 390                                 // Check if we reached the last block at this
 391                                 // level, or if there was a change in this block
 392                                 if (offset >= mip_map_[level].length ||
 393                                         (get_subsample(level, offset) &
 394                                                 sig_mask))
 395                                         break;
 396
 397                                 if ((offset & ~((uint64_t)(~0) << MipMapScalePower)) == 0) {
 398                                         // If we are now at the beginning of a
 399                                         // higher level mip-map block ascend one
 400                                         // level
 401                                         if (level + 1 >= ScaleStepCount ||
 402                                                 !mip_map_[level + 1].data)
 403                                                 break;
 404
 405                                         level++;
 406                                 } else {
 407                                         // Slide right to the beginning of the
 408                                         // next mip map block
 409                                         index = pow2_ceil(index + 1,
 410                                                 level_scale_power);
 411                                 }
 412                         }
 413
 414                         // Zoom in, and slide right until we encounter a change,
 415                         // and repeat until we reach min_level
 416                         while (true) {
 417                                 assert(mip_map_[level].data);
 418
 419                                 const int level_scale_power =
 420                                         (level + 1) * MipMapScalePower;
 421                                 const uint64_t offset =
 422                                         index >> level_scale_power;
 423
 424                                 // Check if we reached the last block at this
 425                                 // level, or if there was a change in this block
 426                                 if (offset >= mip_map_[level].length ||
 427                                                 (get_subsample(level, offset) &
 428                                                 sig_mask)) {
 429                                         // Zoom in unless we reached the minimum
 430                                         // zoom
 431                                         if (level == min_level)
 432                                                 break;
 433
 434                                         level--;
 435                                 } else {
 436                                         // Slide right to the beginning of the
 437                                         // next mip map block
 438                                         index = pow2_ceil(index + 1,
 439                                                 level_scale_power);
 440                                 }
 441                         }
 442
 443                         // If individual samples within the limit of resolution,
 444                         // do a linear search for the next transition within the
 445                         // block
 446                         if (min_length < MipMapScaleFactor) {
 447                                 for (; index < end; index++) {
 448                                         const bool sample = (get_unpacked_sample(index) &
 449                                                 sig_mask) != 0;
 450                                         if (sample != last_sample)
 451                                                 break;
 452                                 }
 453                         }
 454                 }
 455
 456                 //----- Store the edge -----//
 457
 458                 // Take the last sample of the quanization block
 459                 const int64_t final_index = index + block_length;
 460                 if (index + block_length > end)
 461                         break;
 462
 463                 // Store the final state
 464                 const bool final_sample =
 465                         (get_unpacked_sample(final_index - 1) & sig_mask) != 0;
 466                 edges.emplace_back(index, final_sample);
 467
 468                 index = final_index;
 469                 last_sample = final_sample;
 470         }
 471
 472         // Add the final state
 473         const bool end_sample = get_unpacked_sample(end) & sig_mask;
 474         if (last_sample != end_sample)
 475                 edges.emplace_back(end, end_sample);
 476         edges.emplace_back(end + 1, end_sample);
 477 }
 478
 479 uint64_t LogicSegment::get_subsample(int level, uint64_t offset) const
 480 {
 481         assert(level >= 0);
 482         assert(mip_map_[level].data);
 483         return unpack_sample((uint8_t*)mip_map_[level].data +
 484                 unit_size_ * offset);
 485 }
 486
 487 uint64_t LogicSegment::pow2_ceil(uint64_t x, unsigned int power)
 488 {
 489         const uint64_t p = 1 << power;
 490         return (x + p - 1) / p * p;
 491 }
 492
 493 } // namespace data
 494 } // namespace pv