| File: | var/lib/jenkins/workspace/firefox-scan-build/dom/media/webaudio/blink/ReverbConvolver.cpp |
| Warning: | line 230, column 13 Although the value stored to 'readIndex' is used in the enclosing expression, the value is never actually read from 'readIndex' |
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| 1 | /* |
| 2 | * Copyright (C) 2010 Google Inc. All rights reserved. |
| 3 | * |
| 4 | * Redistribution and use in source and binary forms, with or without |
| 5 | * modification, are permitted provided that the following conditions |
| 6 | * are met: |
| 7 | * |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of |
| 14 | * its contributors may be used to endorse or promote products derived |
| 15 | * from this software without specific prior written permission. |
| 16 | * |
| 17 | * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY |
| 18 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| 19 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| 20 | * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY |
| 21 | * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| 22 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 23 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| 24 | * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 25 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 26 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 27 | */ |
| 28 | |
| 29 | #include "ReverbConvolver.h" |
| 30 | #include "ReverbConvolverStage.h" |
| 31 | |
| 32 | using namespace mozilla; |
| 33 | |
| 34 | namespace WebCore { |
| 35 | |
| 36 | const int InputBufferSize = 8 * 16384; |
| 37 | |
| 38 | // We only process the leading portion of the impulse response in the real-time |
| 39 | // thread. We don't exceed this length. It turns out then, that the background |
| 40 | // thread has about 278msec of scheduling slop. Empirically, this has been found |
| 41 | // to be a good compromise between giving enough time for scheduling slop, while |
| 42 | // still minimizing the amount of processing done in the primary (high-priority) |
| 43 | // thread. This was found to be a good value on Mac OS X, and may work well on |
| 44 | // other platforms as well, assuming the very rough scheduling latencies are |
| 45 | // similar on these time-scales. Of course, this code may need to be tuned for |
| 46 | // individual platforms if this assumption is found to be incorrect. |
| 47 | const size_t RealtimeFrameLimit = 8192 + 4096 // ~278msec @ 44.1KHz |
| 48 | - WEBAUDIO_BLOCK_SIZE; |
| 49 | // First stage will have size MinFFTSize - successive stages will double in |
| 50 | // size each time until we hit the maximum size. |
| 51 | const size_t MinFFTSize = 256; |
| 52 | // If we are using background threads then don't exceed this FFT size for the |
| 53 | // stages which run in the real-time thread. This avoids having only one or |
| 54 | // two large stages (size 16384 or so) at the end which take a lot of time |
| 55 | // every several processing slices. This way we amortize the cost over more |
| 56 | // processing slices. |
| 57 | const size_t MaxRealtimeFFTSize = 4096; |
| 58 | |
| 59 | ReverbConvolver::ReverbConvolver(const float* impulseResponseData, |
| 60 | size_t impulseResponseLength, |
| 61 | size_t maxFFTSize, size_t convolverRenderPhase, |
| 62 | bool useBackgroundThreads, |
| 63 | bool* aAllocationFailure) |
| 64 | : m_impulseResponseLength(impulseResponseLength), |
| 65 | m_inputBuffer(InputBufferSize), |
| 66 | m_backgroundThread("ConvolverWorker"), |
| 67 | m_backgroundThreadMonitor("ConvolverMonitor"), |
| 68 | m_useBackgroundThreads(useBackgroundThreads), |
| 69 | m_wantsToExit(false), |
| 70 | m_moreInputBuffered(false) { |
| 71 | *aAllocationFailure = !m_accumulationBuffer.allocate(impulseResponseLength + |
| 72 | WEBAUDIO_BLOCK_SIZE); |
| 73 | if (*aAllocationFailure) { |
| 74 | return; |
| 75 | } |
| 76 | // For the moment, a good way to know if we have real-time constraint is to |
| 77 | // check if we're using background threads. Otherwise, assume we're being run |
| 78 | // from a command-line tool. |
| 79 | bool hasRealtimeConstraint = useBackgroundThreads; |
| 80 | |
| 81 | const float* response = impulseResponseData; |
| 82 | size_t totalResponseLength = impulseResponseLength; |
| 83 | |
| 84 | // The total latency is zero because the first FFT stage is small enough |
| 85 | // to return output in the first block. |
| 86 | size_t reverbTotalLatency = 0; |
| 87 | |
| 88 | size_t stageOffset = 0; |
| 89 | size_t stagePhase = 0; |
| 90 | size_t fftSize = MinFFTSize; |
| 91 | while (stageOffset < totalResponseLength) { |
| 92 | size_t stageSize = fftSize / 2; |
| 93 | |
| 94 | // For the last stage, it's possible that stageOffset is such that we're |
| 95 | // straddling the end of the impulse response buffer (if we use stageSize), |
| 96 | // so reduce the last stage's length... |
| 97 | if (stageSize + stageOffset > totalResponseLength) { |
| 98 | stageSize = totalResponseLength - stageOffset; |
| 99 | // Use smallest FFT that is large enough to cover the last stage. |
| 100 | fftSize = MinFFTSize; |
| 101 | while (stageSize * 2 > fftSize) { |
| 102 | fftSize *= 2; |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | // This "staggers" the time when each FFT happens so they don't all happen |
| 107 | // at the same time |
| 108 | int renderPhase = convolverRenderPhase + stagePhase; |
| 109 | |
| 110 | UniquePtr<ReverbConvolverStage> stage(new ReverbConvolverStage( |
| 111 | response, totalResponseLength, reverbTotalLatency, stageOffset, |
| 112 | stageSize, fftSize, renderPhase, &m_accumulationBuffer)); |
| 113 | |
| 114 | bool isBackgroundStage = false; |
| 115 | |
| 116 | if (this->useBackgroundThreads() && stageOffset > RealtimeFrameLimit) { |
| 117 | m_backgroundStages.AppendElement(std::move(stage)); |
| 118 | isBackgroundStage = true; |
| 119 | } else |
| 120 | m_stages.AppendElement(std::move(stage)); |
| 121 | |
| 122 | // Figure out next FFT size |
| 123 | fftSize *= 2; |
| 124 | |
| 125 | stageOffset += stageSize; |
| 126 | |
| 127 | if (hasRealtimeConstraint && !isBackgroundStage && |
| 128 | fftSize > MaxRealtimeFFTSize) { |
| 129 | fftSize = MaxRealtimeFFTSize; |
| 130 | // Custom phase positions for all but the first of the realtime |
| 131 | // stages of largest size. These spread out the work of the |
| 132 | // larger realtime stages. None of the FFTs of size 1024, 2048 or |
| 133 | // 4096 are performed when processing the same block. The first |
| 134 | // MaxRealtimeFFTSize = 4096 stage, at the end of the doubling, |
| 135 | // performs its FFT at block 7. The FFTs of size 2048 are |
| 136 | // performed in blocks 3 + 8 * n and size 1024 at 1 + 4 * n. |
| 137 | const uint32_t phaseLookup[] = {14, 0, 10, 4}; |
| 138 | stagePhase = WEBAUDIO_BLOCK_SIZE * |
| 139 | phaseLookup[m_stages.Length() % ArrayLength(phaseLookup)]; |
| 140 | } else if (fftSize > maxFFTSize) { |
| 141 | fftSize = maxFFTSize; |
| 142 | // A prime offset spreads out FFTs in a way that all |
| 143 | // available phase positions will be used if there are sufficient |
| 144 | // stages. |
| 145 | stagePhase += 5 * WEBAUDIO_BLOCK_SIZE; |
| 146 | } else if (stageSize > WEBAUDIO_BLOCK_SIZE) { |
| 147 | // As the stages are doubling in size, the next FFT will occur |
| 148 | // mid-way between FFTs for this stage. |
| 149 | stagePhase = stageSize - WEBAUDIO_BLOCK_SIZE; |
| 150 | } |
| 151 | } |
| 152 | |
| 153 | // Start up background thread |
| 154 | // FIXME: would be better to up the thread priority here. It doesn't need to |
| 155 | // be real-time, but higher than the default... |
| 156 | if (this->useBackgroundThreads() && m_backgroundStages.Length() > 0) { |
| 157 | if (!m_backgroundThread.Start()) { |
| 158 | NS_WARNING("Cannot start convolver thread.")NS_DebugBreak(NS_DEBUG_WARNING, "Cannot start convolver thread." , nullptr, "/var/lib/jenkins/workspace/firefox-scan-build/dom/media/webaudio/blink/ReverbConvolver.cpp" , 158); |
| 159 | return; |
| 160 | } |
| 161 | m_backgroundThread.message_loop()->PostTask(NewNonOwningRunnableMethod( |
| 162 | "WebCore::ReverbConvolver::backgroundThreadEntry", this, |
| 163 | &ReverbConvolver::backgroundThreadEntry)); |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | ReverbConvolver::~ReverbConvolver() { |
| 168 | // Wait for background thread to stop |
| 169 | if (useBackgroundThreads() && m_backgroundThread.IsRunning()) { |
| 170 | m_wantsToExit = true; |
| 171 | |
| 172 | // Wake up thread so it can return |
| 173 | { |
| 174 | MonitorAutoLock locker(m_backgroundThreadMonitor); |
| 175 | m_moreInputBuffered = true; |
| 176 | m_backgroundThreadMonitor.Notify(); |
| 177 | } |
| 178 | |
| 179 | m_backgroundThread.Stop(); |
| 180 | } |
| 181 | } |
| 182 | |
| 183 | size_t ReverbConvolver::sizeOfIncludingThis( |
| 184 | mozilla::MallocSizeOf aMallocSizeOf) const { |
| 185 | size_t amount = aMallocSizeOf(this); |
| 186 | amount += m_stages.ShallowSizeOfExcludingThis(aMallocSizeOf); |
| 187 | for (size_t i = 0; i < m_stages.Length(); i++) { |
| 188 | if (m_stages[i]) { |
| 189 | amount += m_stages[i]->sizeOfIncludingThis(aMallocSizeOf); |
| 190 | } |
| 191 | } |
| 192 | |
| 193 | amount += m_backgroundStages.ShallowSizeOfExcludingThis(aMallocSizeOf); |
| 194 | for (size_t i = 0; i < m_backgroundStages.Length(); i++) { |
| 195 | if (m_backgroundStages[i]) { |
| 196 | amount += m_backgroundStages[i]->sizeOfIncludingThis(aMallocSizeOf); |
| 197 | } |
| 198 | } |
| 199 | |
| 200 | // NB: The buffer sizes are static, so even though they might be accessed |
| 201 | // in another thread it's safe to measure them. |
| 202 | amount += m_accumulationBuffer.sizeOfExcludingThis(aMallocSizeOf); |
| 203 | amount += m_inputBuffer.sizeOfExcludingThis(aMallocSizeOf); |
| 204 | |
| 205 | // Possible future measurements: |
| 206 | // - m_backgroundThread |
| 207 | // - m_backgroundThreadMonitor |
| 208 | return amount; |
| 209 | } |
| 210 | |
| 211 | void ReverbConvolver::backgroundThreadEntry() { |
| 212 | while (!m_wantsToExit) { |
| 213 | // Wait for realtime thread to give us more input |
| 214 | m_moreInputBuffered = false; |
| 215 | { |
| 216 | MonitorAutoLock locker(m_backgroundThreadMonitor); |
| 217 | while (!m_moreInputBuffered && !m_wantsToExit) |
| 218 | m_backgroundThreadMonitor.Wait(); |
| 219 | } |
| 220 | |
| 221 | // Process all of the stages until their read indices reach the input |
| 222 | // buffer's write index |
| 223 | int writeIndex = m_inputBuffer.writeIndex(); |
| 224 | |
| 225 | // Even though it doesn't seem like every stage needs to maintain its own |
| 226 | // version of readIndex we do this in case we want to run in more than one |
| 227 | // background thread. |
| 228 | int readIndex; |
| 229 | |
| 230 | while ((readIndex = m_backgroundStages[0]->inputReadIndex()) != |
Although the value stored to 'readIndex' is used in the enclosing expression, the value is never actually read from 'readIndex' | |
| 231 | writeIndex) { // FIXME: do better to detect buffer overrun... |
| 232 | // Accumulate contributions from each stage |
| 233 | for (size_t i = 0; i < m_backgroundStages.Length(); ++i) |
| 234 | m_backgroundStages[i]->processInBackground(this); |
| 235 | } |
| 236 | } |
| 237 | } |
| 238 | |
| 239 | void ReverbConvolver::process(const float* sourceChannelData, |
| 240 | float* destinationChannelData) { |
| 241 | const float* source = sourceChannelData; |
| 242 | float* destination = destinationChannelData; |
| 243 | bool isDataSafe = source && destination; |
| 244 | MOZ_ASSERT(isDataSafe)do { static_assert( mozilla::detail::AssertionConditionType< decltype(isDataSafe)>::isValid, "invalid assertion condition" ); if ((__builtin_expect(!!(!(!!(isDataSafe))), 0))) { do { } while (false); MOZ_ReportAssertionFailure("isDataSafe", "/var/lib/jenkins/workspace/firefox-scan-build/dom/media/webaudio/blink/ReverbConvolver.cpp" , 244); AnnotateMozCrashReason("MOZ_ASSERT" "(" "isDataSafe" ")" ); do { *((volatile int*)__null) = 244; __attribute__((nomerge )) ::abort(); } while (false); } } while (false); |
| 245 | if (!isDataSafe) return; |
| 246 | |
| 247 | // Feed input buffer (read by all threads) |
| 248 | m_inputBuffer.write(source, WEBAUDIO_BLOCK_SIZE); |
| 249 | |
| 250 | // Accumulate contributions from each stage |
| 251 | for (size_t i = 0; i < m_stages.Length(); ++i) m_stages[i]->process(source); |
| 252 | |
| 253 | // Finally read from accumulation buffer |
| 254 | m_accumulationBuffer.readAndClear(destination, WEBAUDIO_BLOCK_SIZE); |
| 255 | |
| 256 | // Now that we've buffered more input, wake up our background thread. |
| 257 | |
| 258 | // Not using a MonitorAutoLock looks strange, but we use a TryLock() instead |
| 259 | // because this is run on the real-time thread where it is a disaster for the |
| 260 | // lock to be contended (causes audio glitching). It's OK if we fail to |
| 261 | // signal from time to time, since we'll get to it the next time we're called. |
| 262 | // We're called repeatedly and frequently (around every 3ms). The background |
| 263 | // thread is processing well into the future and has a considerable amount of |
| 264 | // leeway here... |
| 265 | if (m_backgroundThreadMonitor.TryLock()) { |
| 266 | m_moreInputBuffered = true; |
| 267 | m_backgroundThreadMonitor.Notify(); |
| 268 | m_backgroundThreadMonitor.Unlock(); |
| 269 | } |
| 270 | } |
| 271 | |
| 272 | } // namespace WebCore |