Make AudioIOBufferHelper.h cache friendly.

Improves performance of project loading substantively.

Signed-off-by: Emily Mabrey <emabrey@tenacityaudio.org>
Helped-by: Alex Disibio <alexdisibio@gmail.com>

src/AudioIO.cpp

@@ -3843,10 +3843,9 @@ bool AudioIoCallback::FillOutputBuffers(
       return true;
    }
 
-   // ------ MEMORY ALLOCATION ----------------------
+   //Real time process section
+   {
        std::unique_ptr<AudioIOBufferHelper> bufHelper = std::make_unique<AudioIOBufferHelper>(numPlaybackChannels, framesPerBuffer);
-   // ------ End of MEMORY ALLOCATION ---------------
-
        auto& em = RealtimeEffectManager::Get();
        em.RealtimeProcessStart();
 
@@ -3855,8 +3854,7 @@ bool AudioIoCallback::FillOutputBuffers(
        int chanCnt = 0;
 
        // Choose a common size to take from all ring buffers
-   const auto toGet =
+       const auto toGet = std::min<size_t>(framesPerBuffer, GetCommonlyReadyPlayback());
-      std::min<size_t>(framesPerBuffer, GetCommonlyReadyPlayback());
 
        // The drop and dropQuickly booleans are so named for historical reasons.
        // JKC: The original code attempted to be faster by doing nothing on silenced audio.
@@ -3873,8 +3871,7 @@ bool AudioIoCallback::FillOutputBuffers(
 
        bool drop = false;        // Track should become silent.
        bool dropQuickly = false; // Track has already been faded to silence.
-   for (unsigned t = 0; t < numPlaybackTracks; t++)
+       for (unsigned t = 0; t < numPlaybackTracks; t++) {
-   {
            WaveTrack* vt = mPlaybackTracks[t].get();
            bufHelper.get()->chans[chanCnt] = vt;
 
@@ -3889,8 +3886,7 @@ bool AudioIoCallback::FillOutputBuffers(
            bool firstChannel = vt->IsLeader();
            bool lastChannel = !nextTrack || nextTrack->IsLeader();
 
-      if ( firstChannel )
+           if (firstChannel) {
-      {
                selected = vt->GetSelected();
                // IF mono THEN clear 'the other' channel.
                if (lastChannel && (numPlaybackChannels > 1)) {
@@ -3906,14 +3902,11 @@ bool AudioIoCallback::FillOutputBuffers(
 
            decltype(framesPerBuffer) len = 0;
 
-      if (dropQuickly)
+           if (dropQuickly) {
-      {
                len = mPlaybackBuffers[t]->Discard(toGet);
                // keep going here.  
                // we may still need to issue a paComplete.
-      }
+           } else {
-      else
-      {
                len = mPlaybackBuffers[t]->Get((samplePtr)bufHelper.get()->tempBufs[chanCnt],
                                               floatSample,
                                               toGet);
@@ -3963,8 +3956,7 @@ bool AudioIoCallback::FillOutputBuffers(
            //
            // Each channel in the tracks can output to more than one channel on the device.
            // For example mono channels output to both left and right output channels.
-      if (len > 0) for (int c = 0; c < chanCnt; c++)
+           if (len > 0) for (int c = 0; c < chanCnt; c++) {
-      {
                vt = bufHelper.get()->chans[c];
 
                if (vt->GetChannelIgnoringPan() == Track::LeftChannel || vt->GetChannelIgnoringPan() == Track::MonoChannel)
@@ -3977,6 +3969,7 @@ bool AudioIoCallback::FillOutputBuffers(
            chanCnt = 0;
        }
 
+
        // Poke: If there are no playback tracks, then the earlier check
        // about the time indicator being past the end won't happen;
        // do it here instead (but not if looping or scrubbing)
@@ -3986,6 +3979,8 @@ bool AudioIoCallback::FillOutputBuffers(
        // wxASSERT( maxLen == toGet );
 
        em.RealtimeProcessEnd();
+       delete bufHelper.release();
+   }
    mLastPlaybackTimeMillis = ::wxGetUTCTimeMillis();
 
    ClampBuffer( outputFloats, framesPerBuffer*numPlaybackChannels );

src/AudioIOBufferHelper.h

@@ -23,19 +23,24 @@ class AudioIOBufferHelper
         this->chans = safenew WaveTrack * [numPlaybackChannels];
         this->tempBufs = safenew float* [numPlaybackChannels];
 
-            for (unsigned int c = 0; c < numPlaybackChannels; c++) {
+        tempBufs[0] = safenew float[(size_t)numPlaybackChannels * framesPerBuffer];
-                tempBufs[c] = safenew float[framesPerBuffer];
+
+        for (unsigned int c = 1; c < numPlaybackChannels; c++) {
+            tempBufs[c] = tempBufs[c - 1] + framesPerBuffer;
         }
     }
 
     ~AudioIOBufferHelper() {
-            for (unsigned int c = 0; c < numPlaybackChannels; c++) {
+
-                delete[] tempBufs[c];
+        delete[] tempBufs[0];
-            }
 
         delete[] tempBufs;
 
+        tempBufs = nullptr;
+
         delete[] chans;
+
+        chans = nullptr;
     }
 };