2 * This file is part of the PulseView project.
4 * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
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.
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.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
28 #include <boost/foreach.hpp>
30 #include "logicsnapshot.h"
32 using namespace boost;
38 const int LogicSnapshot::MipMapScalePower = 4;
39 const int LogicSnapshot::MipMapScaleFactor = 1 << MipMapScalePower;
40 const float LogicSnapshot::LogMipMapScaleFactor = logf(MipMapScaleFactor);
41 const uint64_t LogicSnapshot::MipMapDataUnit = 64*1024; // bytes
43 LogicSnapshot::LogicSnapshot(const sr_datafeed_logic &logic) :
44 Snapshot(logic.unitsize),
45 _last_append_sample(0)
47 lock_guard<recursive_mutex> lock(_mutex);
48 memset(_mip_map, 0, sizeof(_mip_map));
49 append_payload(logic);
52 LogicSnapshot::~LogicSnapshot()
54 lock_guard<recursive_mutex> lock(_mutex);
55 BOOST_FOREACH(MipMapLevel &l, _mip_map)
59 void LogicSnapshot::append_payload(
60 const sr_datafeed_logic &logic)
62 assert(_unit_size == logic.unitsize);
63 assert((logic.length % _unit_size) == 0);
65 lock_guard<recursive_mutex> lock(_mutex);
67 append_data(logic.data, logic.length / _unit_size);
69 // Generate the first mip-map from the data
70 append_payload_to_mipmap();
73 void LogicSnapshot::reallocate_mip_map(MipMapLevel &m)
75 const uint64_t new_data_length = ((m.length + MipMapDataUnit - 1) /
76 MipMapDataUnit) * MipMapDataUnit;
77 if (new_data_length > m.data_length)
79 m.data_length = new_data_length;
80 m.data = realloc(m.data, new_data_length * _unit_size);
84 void LogicSnapshot::append_payload_to_mipmap()
86 MipMapLevel &m0 = _mip_map[0];
88 const uint8_t *src_ptr;
91 unsigned int diff_counter;
93 // Expand the data buffer to fit the new samples
94 prev_length = m0.length;
95 m0.length = _sample_count / MipMapScaleFactor;
97 // Break off if there are no new samples to compute
98 if (m0.length == prev_length)
101 reallocate_mip_map(m0);
103 dest_ptr = (uint8_t*)m0.data + prev_length * _unit_size;
105 // Iterate through the samples to populate the first level mipmap
107 diff_counter = MipMapScaleFactor;
108 const uint8_t *end_src_ptr = (uint8_t*)_data +
109 m0.length * _unit_size * MipMapScaleFactor;
110 for (src_ptr = (uint8_t*)_data +
111 prev_length * _unit_size * MipMapScaleFactor;
112 src_ptr < end_src_ptr;)
114 // Accumulate transitions which have occurred in this sample
116 diff_counter = MipMapScaleFactor;
117 while (diff_counter-- > 0)
119 const uint64_t sample = *(uint64_t*)src_ptr;
120 accumulator |= _last_append_sample ^ sample;
121 _last_append_sample = sample;
122 src_ptr += _unit_size;
125 *(uint64_t*)dest_ptr = accumulator;
126 dest_ptr += _unit_size;
129 // Compute higher level mipmaps
130 for (unsigned int level = 1; level < ScaleStepCount; level++)
132 MipMapLevel &m = _mip_map[level];
133 const MipMapLevel &ml = _mip_map[level-1];
135 // Expand the data buffer to fit the new samples
136 prev_length = m.length;
137 m.length = ml.length / MipMapScaleFactor;
139 // Break off if there are no more samples to computed
140 if (m.length == prev_length)
143 reallocate_mip_map(m);
145 // Subsample the level lower level
146 src_ptr = (uint8_t*)ml.data +
147 _unit_size * prev_length * MipMapScaleFactor;
148 const uint8_t *end_dest_ptr =
149 (uint8_t*)m.data + _unit_size * m.length;
150 for (dest_ptr = (uint8_t*)m.data +
151 _unit_size * prev_length;
152 dest_ptr < end_dest_ptr;
153 dest_ptr += _unit_size)
156 diff_counter = MipMapScaleFactor;
157 while (diff_counter-- > 0)
159 accumulator |= *(uint64_t*)src_ptr;
160 src_ptr += _unit_size;
163 *(uint64_t*)dest_ptr = accumulator;
168 uint64_t LogicSnapshot::get_sample(uint64_t index) const
171 assert(index < _sample_count);
173 return *(uint64_t*)((uint8_t*)_data + index * _unit_size);
176 void LogicSnapshot::get_subsampled_edges(
177 std::vector<EdgePair> &edges,
178 uint64_t start, uint64_t end,
179 float min_length, int sig_index)
181 uint64_t index = start;
186 assert(end <= get_sample_count());
187 assert(start <= end);
188 assert(min_length > 0);
189 assert(sig_index >= 0);
190 assert(sig_index < SR_MAX_NUM_PROBES);
192 lock_guard<recursive_mutex> lock(_mutex);
194 const uint64_t block_length = (uint64_t)max(min_length, 1.0f);
195 const unsigned int min_level = max((int)floorf(logf(min_length) /
196 LogMipMapScaleFactor) - 1, 0);
197 const uint64_t sig_mask = 1ULL << sig_index;
199 // Store the initial state
200 last_sample = (get_sample(start) & sig_mask) != 0;
201 edges.push_back(pair<int64_t, bool>(index++, last_sample));
203 while (index + block_length <= end)
205 //----- Continue to search -----//
209 if (min_length < MipMapScaleFactor)
211 // Search individual samples up to the beginning of
212 // the next first level mip map block
213 const uint64_t final_index = min(end,
214 pow2_ceil(index, MipMapScalePower));
216 for (; index < final_index &&
217 (index & ~(~0 << MipMapScalePower)) != 0;
221 (get_sample(index) & sig_mask) != 0;
223 // If there was a change we cannot fast forward
224 if (sample != last_sample) {
225 fast_forward = false;
232 // If resolution is less than a mip map block,
233 // round up to the beginning of the mip-map block
234 // for this level of detail
235 const int min_level_scale_power =
236 (level + 1) * MipMapScalePower;
237 index = pow2_ceil(index, min_level_scale_power);
241 // We can fast forward only if there was no change
243 (get_sample(index) & sig_mask) != 0;
244 fast_forward = last_sample == sample;
249 // Fast forward: This involves zooming out to higher
250 // levels of the mip map searching for changes, then
251 // zooming in on them to find the point where the edge
254 // Slide right and zoom out at the beginnings of mip-map
255 // blocks until we encounter a change
257 const int level_scale_power =
258 (level + 1) * MipMapScalePower;
259 const uint64_t offset =
260 index >> level_scale_power;
262 // Check if we reached the last block at this
263 // level, or if there was a change in this block
264 if (offset >= _mip_map[level].length ||
265 (get_subsample(level, offset) &
269 if ((offset & ~(~0 << MipMapScalePower)) == 0) {
270 // If we are now at the beginning of a
271 // higher level mip-map block ascend one
273 if (level + 1 >= ScaleStepCount ||
274 !_mip_map[level + 1].data)
279 // Slide right to the beginning of the
280 // next mip map block
281 index = pow2_ceil(index + 1,
286 // Zoom in, and slide right until we encounter a change,
287 // and repeat until we reach min_level
289 assert(_mip_map[level].data);
291 const int level_scale_power =
292 (level + 1) * MipMapScalePower;
293 const uint64_t offset =
294 index >> level_scale_power;
296 // Check if we reached the last block at this
297 // level, or if there was a change in this block
298 if (offset >= _mip_map[level].length ||
299 (get_subsample(level, offset) &
301 // Zoom in unless we reached the minimum
303 if (level == min_level)
308 // Slide right to the beginning of the
309 // next mip map block
310 index = pow2_ceil(index + 1,
315 // If individual samples within the limit of resolution,
316 // do a linear search for the next transition within the
318 if (min_length < MipMapScaleFactor) {
319 for (; index < end; index++) {
320 const bool sample = (get_sample(index) &
322 if (sample != last_sample)
328 //----- Store the edge -----//
330 // Take the last sample of the quanization block
331 const int64_t final_index = index + block_length;
332 if (index + block_length > end)
335 // Store the final state
336 const bool final_sample =
337 (get_sample(final_index - 1) & sig_mask) != 0;
338 edges.push_back(pair<int64_t, bool>(index, final_sample));
341 last_sample = final_sample;
344 // Add the final state
345 edges.push_back(pair<int64_t, bool>(end,
346 get_sample(end) & sig_mask));
349 uint64_t LogicSnapshot::get_subsample(int level, uint64_t offset) const
352 assert(_mip_map[level].data);
353 return *(uint64_t*)((uint8_t*)_mip_map[level].data +
354 _unit_size * offset);
357 uint64_t LogicSnapshot::pow2_ceil(uint64_t x, unsigned int power)
359 const uint64_t p = 1 << power;
360 return (x + p - 1) / p * p;