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