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);
64 lock_guard<recursive_mutex> lock(_mutex);
66 append_data(logic.data, logic.length);
68 // Generate the first mip-map from the data
69 append_payload_to_mipmap();
72 void LogicSnapshot::reallocate_mip_map(MipMapLevel &m)
74 const uint64_t new_data_length = ((m.length + MipMapDataUnit - 1) /
75 MipMapDataUnit) * MipMapDataUnit;
76 if (new_data_length > m.data_length)
78 m.data_length = new_data_length;
79 m.data = realloc(m.data, new_data_length * _unit_size);
83 void LogicSnapshot::append_payload_to_mipmap()
85 MipMapLevel &m0 = _mip_map[0];
87 const uint8_t *src_ptr;
90 unsigned int diff_counter;
92 // Expand the data buffer to fit the new samples
93 prev_length = m0.length;
94 m0.length = _sample_count / MipMapScaleFactor;
96 // Break off if there are no new samples to compute
97 if (m0.length == prev_length)
100 reallocate_mip_map(m0);
102 dest_ptr = (uint8_t*)m0.data + prev_length * _unit_size;
104 // Iterate through the samples to populate the first level mipmap
106 diff_counter = MipMapScaleFactor;
107 const uint8_t *end_src_ptr = (uint8_t*)_data +
108 m0.length * _unit_size * MipMapScaleFactor;
109 for (src_ptr = (uint8_t*)_data +
110 prev_length * _unit_size * MipMapScaleFactor;
111 src_ptr < end_src_ptr;)
113 // Accumulate transitions which have occurred in this sample
115 diff_counter = MipMapScaleFactor;
116 while (diff_counter-- > 0)
118 const uint64_t sample = *(uint64_t*)src_ptr;
119 accumulator |= _last_append_sample ^ sample;
120 _last_append_sample = sample;
121 src_ptr += _unit_size;
124 *(uint64_t*)dest_ptr = accumulator;
125 dest_ptr += _unit_size;
128 // Compute higher level mipmaps
129 for (unsigned int level = 1; level < ScaleStepCount; level++)
131 MipMapLevel &m = _mip_map[level];
132 const MipMapLevel &ml = _mip_map[level-1];
134 // Expand the data buffer to fit the new samples
135 prev_length = m.length;
136 m.length = ml.length / MipMapScaleFactor;
138 // Break off if there are no more samples to computed
139 if (m.length == prev_length)
142 reallocate_mip_map(m);
144 // Subsample the level lower level
145 src_ptr = (uint8_t*)ml.data +
146 _unit_size * prev_length * MipMapScaleFactor;
147 const uint8_t *end_dest_ptr =
148 (uint8_t*)m.data + _unit_size * m.length;
149 for (dest_ptr = (uint8_t*)m.data +
150 _unit_size * prev_length;
151 dest_ptr < end_dest_ptr;
152 dest_ptr += _unit_size)
155 diff_counter = MipMapScaleFactor;
156 while (diff_counter-- > 0)
158 accumulator |= *(uint64_t*)src_ptr;
159 src_ptr += _unit_size;
162 *(uint64_t*)dest_ptr = accumulator;
167 uint64_t LogicSnapshot::get_sample(uint64_t index) const
170 assert(index < _sample_count);
172 return *(uint64_t*)((uint8_t*)_data + index * _unit_size);
175 void LogicSnapshot::get_subsampled_edges(
176 std::vector<EdgePair> &edges,
177 uint64_t start, uint64_t end,
178 float min_length, int sig_index)
180 uint64_t index = start;
185 assert(end <= get_sample_count());
186 assert(start <= end);
187 assert(min_length > 0);
188 assert(sig_index >= 0);
189 assert(sig_index < SR_MAX_NUM_PROBES);
191 lock_guard<recursive_mutex> lock(_mutex);
193 const uint64_t block_length = (uint64_t)max(min_length, 1.0f);
194 const unsigned int min_level = max((int)floorf(logf(min_length) /
195 LogMipMapScaleFactor) - 1, 0);
196 const uint64_t sig_mask = 1ULL << sig_index;
198 // Store the initial state
199 last_sample = (get_sample(start) & sig_mask) != 0;
200 edges.push_back(pair<int64_t, bool>(index++, last_sample));
202 while (index + block_length <= end)
204 //----- Continue to search -----//
208 if (min_length < MipMapScaleFactor)
210 // Search individual samples up to the beginning of
211 // the next first level mip map block
212 const uint64_t final_index = min(end,
213 pow2_ceil(index, MipMapScalePower));
215 for (; index < final_index &&
216 (index & ~(~0 << MipMapScalePower)) != 0;
220 (get_sample(index) & sig_mask) != 0;
222 // If there was a change we cannot fast forward
223 if (sample != last_sample) {
224 fast_forward = false;
231 // If resolution is less than a mip map block,
232 // round up to the beginning of the mip-map block
233 // for this level of detail
234 const int min_level_scale_power =
235 (level + 1) * MipMapScalePower;
236 index = pow2_ceil(index, min_level_scale_power);
240 // We can fast forward only if there was no change
242 (get_sample(index) & sig_mask) != 0;
243 fast_forward = last_sample == sample;
248 // Fast forward: This involves zooming out to higher
249 // levels of the mip map searching for changes, then
250 // zooming in on them to find the point where the edge
253 // Slide right and zoom out at the beginnings of mip-map
254 // blocks until we encounter a change
256 const int level_scale_power =
257 (level + 1) * MipMapScalePower;
258 const uint64_t offset =
259 index >> level_scale_power;
261 // Check if we reached the last block at this
262 // level, or if there was a change in this block
263 if (offset >= _mip_map[level].length ||
264 (get_subsample(level, offset) &
268 if ((offset & ~(~0 << MipMapScalePower)) == 0) {
269 // If we are now at the beginning of a
270 // higher level mip-map block ascend one
272 if (level + 1 >= ScaleStepCount ||
273 !_mip_map[level + 1].data)
278 // Slide right to the beginning of the
279 // next mip map block
280 index = pow2_ceil(index + 1,
285 // Zoom in, and slide right until we encounter a change,
286 // and repeat until we reach min_level
288 assert(_mip_map[level].data);
290 const int level_scale_power =
291 (level + 1) * MipMapScalePower;
292 const uint64_t offset =
293 index >> level_scale_power;
295 // Check if we reached the last block at this
296 // level, or if there was a change in this block
297 if (offset >= _mip_map[level].length ||
298 (get_subsample(level, offset) &
300 // Zoom in unless we reached the minimum
302 if (level == min_level)
307 // Slide right to the beginning of the
308 // next mip map block
309 index = pow2_ceil(index + 1,
314 // If individual samples within the limit of resolution,
315 // do a linear search for the next transition within the
317 if (min_length < MipMapScaleFactor) {
318 for (; index < end; index++) {
319 const bool sample = (get_sample(index) &
321 if (sample != last_sample)
327 //----- Store the edge -----//
329 // Take the last sample of the quanization block
330 const int64_t final_index = index + block_length;
331 if (index + block_length > end)
334 // Store the final state
335 const bool final_sample =
336 (get_sample(final_index - 1) & sig_mask) != 0;
337 edges.push_back(pair<int64_t, bool>(index, final_sample));
340 last_sample = final_sample;
343 // Add the final state
344 edges.push_back(pair<int64_t, bool>(end,
345 get_sample(end) & sig_mask));
348 uint64_t LogicSnapshot::get_subsample(int level, uint64_t offset) const
351 assert(_mip_map[level].data);
352 return *(uint64_t*)((uint8_t*)_mip_map[level].data +
353 _unit_size * offset);
356 uint64_t LogicSnapshot::pow2_ceil(uint64_t x, unsigned int power)
358 const uint64_t p = 1 << power;
359 return (x + p - 1) / p * p;