Merge pull request #2888 from daschuer/restrict

Fix restrict warnings

8 files changed, 65 insertions, 72 deletions

diff --git a/src/engine/effects/engineeffect.cpp b/src/engine/effects/engineeffect.cpp
index 8ef4593028..625bb6de8f 100644
--- a/src/engine/effects/engineeffect.cpp
+++ b/src/engine/effects/engineeffect.cpp
@@ -205,16 +205,16 @@ bool EngineEffect::process(const ChannelHandle& inputHandle,
             if (effectiveEffectEnableState == EffectEnableState::Disabling) {
                 DEBUG_ASSERT(pInput != pOutput); // Fade to dry only works if pInput is not touched by pOutput
                 // Fade out (fade to dry signal)
-                SampleUtil::copy2WithRampingGain(pOutput,
-                        pInput, 0.0, 1.0,
-                        pOutput, 1.0, 0.0,
+                SampleUtil::linearCrossfadeBuffersOut(
+                        pOutput,
+                        pInput,
                         numSamples);
             } else if (effectiveEffectEnableState == EffectEnableState::Enabling) {
                 DEBUG_ASSERT(pInput != pOutput); // Fade to dry only works if pInput is not touched by pOutput
                 // Fade in (fade to wet signal)
-                SampleUtil::copy2WithRampingGain(pOutput,
-                        pInput, 1.0, 0.0,
-                        pOutput, 0.0, 1.0,
+                SampleUtil::linearCrossfadeBuffersIn(
+                        pOutput,
+                        pInput,
                         numSamples);
             }
         }
diff --git a/src/engine/enginebuffer.cpp b/src/engine/enginebuffer.cpp
index e3b58a4c59..cc08b50d61 100644
--- a/src/engine/enginebuffer.cpp
+++ b/src/engine/enginebuffer.cpp
@@ -967,8 +967,10 @@ void EngineBuffer::processTrackLocked(
         // callback and the m_filepos_play is advanced behind the end of the track.
 
         if (m_bCrossfadeReady) {
-           SampleUtil::linearCrossfadeBuffers(
-                    pOutput, m_pCrossfadeBuffer, pOutput, iBufferSize);
+            // Bring pOutput with the new parameters in and fade out the old one,
+            // stored with the old parameters in m_pCrossfadeBuffer
+            SampleUtil::linearCrossfadeBuffersIn(
+                    pOutput, m_pCrossfadeBuffer, iBufferSize);
         }
         // Note: we do not fade here if we pass the end or the start of
         // the track in reverse direction
diff --git a/src/engine/filters/enginefilteriir.h b/src/engine/filters/enginefilteriir.h
index 6a3144286b..225eb609d1 100644
--- a/src/engine/filters/enginefilteriir.h
+++ b/src/engine/filters/enginefilteriir.h
@@ -62,13 +62,21 @@ class EngineFilterIIR : public EngineFilterIIRBase {
     // this is can be used instead off a final process() call before pause
     // It fades to dry or 0 according to the m_startFromDry parameter
     // it is an alternative for using pauseFillter() calls
-    void processAndPauseFilter(const CSAMPLE* pIn, CSAMPLE* pOutput,
-                       const int iBufferSize) {
+    void processAndPauseFilter(
+            const CSAMPLE* pIn,
+            CSAMPLE* pOutput,
+            int iBufferSize) {
         process(pIn, pOutput, iBufferSize);
-        SampleUtil::copy2WithRampingGain(pOutput,
-                pOutput, 1.0, 0,  // fade out filtered
-                pIn, 0, m_startFromDry ? 1.0 : 0,  // fade in dry if requested
-                iBufferSize);
+        if (m_startFromDry) {
+            SampleUtil::linearCrossfadeBuffersOut(
+                    pOutput, // fade out filtered
+                    pIn,     // fade in dry
+                    iBufferSize);
+        } else {
+            SampleUtil::applyRampingGain(
+                    pOutput, 1.0, 0, // fade out filtered
+                    iBufferSize);
+        }
         pauseFilterInner();
     }
 
diff --git a/src/engine/filters/enginefiltermoogladder4.h b/src/engine/filters/enginefiltermoogladder4.h
index 82664508f2..447187b085 100644
--- a/src/engine/filters/enginefiltermoogladder4.h
+++ b/src/engine/filters/enginefiltermoogladder4.h
@@ -108,12 +108,13 @@ class EngineFilterMoogLadderBase : public EngineObjectConstIn {
     // this is can be used instead off a final process() call before pause
     // It fades to dry or 0 according to the m_startFromDry parameter
     // it is an alternative for using pauseFillter() calls
-    void processAndPauseFilter(const CSAMPLE* pIn, CSAMPLE* pOutput,
-                       const int iBufferSize) {
+    void processAndPauseFilter(const CSAMPLE* M_RESTRICT pIn,
+            CSAMPLE* M_RESTRICT pOutput,
+            const int iBufferSize) {
         process(pIn, pOutput, iBufferSize);
-        SampleUtil::copy2WithRampingGain(pOutput,
-                pOutput, 1.0, 0,  // fade out filtered
-                pIn, 0, 1.0,  // fade in dry
+        SampleUtil::linearCrossfadeBuffersOut(
+                pOutput, // fade out filtered
+                pIn,     // fade in dry
                 iBufferSize);
         initBuffers();
     }
@@ -143,7 +144,7 @@ class EngineFilterMoogLadderBase : public EngineObjectConstIn {
                 pOutput[i] = processSample(pIn[i], &m_buf[0]);
                 pOutput[i+1] = processSample(pIn[i+1], &m_buf[1]);
             }
-            
+
         } else {
             m_postGain = m_postGainNew;
             m_kacr = m_kacrNew;
diff --git a/src/engine/readaheadmanager.cpp b/src/engine/readaheadmanager.cpp
index a7f2d95a83..d2b7257cdc 100644
--- a/src/engine/readaheadmanager.cpp
+++ b/src/engine/readaheadmanager.cpp
@@ -156,7 +156,10 @@ SINT ReadAheadManager::getNextSamples(double dRate, CSAMPLE* pOutput,
 
         // do crossfade from the current buffer into the new loop beginning
         if (samples_from_reader != 0) { // avoid division by zero
-            SampleUtil::linearCrossfadeBuffers(pOutput, pOutput, m_pCrossFadeBuffer, samples_from_reader);
+            SampleUtil::linearCrossfadeBuffersOut(
+                    pOutput,
+                    m_pCrossFadeBuffer,
+                    samples_from_reader);
         }
     }
 
diff --git a/src/test/sampleutiltest.cpp b/src/test/sampleutiltest.cpp
index 12ff6ce915..ba231687a9 100644
--- a/src/test/sampleutiltest.cpp
+++ b/src/test/sampleutiltest.cpp
@@ -224,24 +224,6 @@ TEST_F(SampleUtilTest, copy2WithGain) {
     }
 }
 
-TEST_F(SampleUtilTest, copy2WithGainAliased) {
-    for (int i = 0; i < buffers.size(); ++i) {
-        CSAMPLE* buffer = buffers[i];
-        int size = sizes[i];
-        FillBuffer(buffer, 1.0f, size);
-        SampleUtil::copy2WithGain(buffer,
-                                  buffer, 1.0,
-                                  buffer, 1.0,
-                                  size);
-        AssertWholeBufferEquals(buffer, 2.0f, size);
-        SampleUtil::copy2WithGain(buffer,
-                                  buffer, 2.0,
-                                  buffer, 3.0,
-                                  size);
-        AssertWholeBufferEquals(buffer, 10.0f, size);
-    }
-}
-
 TEST_F(SampleUtilTest, copy3WithGain) {
     for (int i = 0; i < buffers.size(); ++i) {
         CSAMPLE* buffer = buffers[i];
@@ -271,26 +253,6 @@ TEST_F(SampleUtilTest, copy3WithGain) {
     }
 }
 
-TEST_F(SampleUtilTest, copy3WithGainAliased) {
-    for (int i = 0; i < buffers.size(); ++i) {
-        CSAMPLE* buffer = buffers[i];
-        int size = sizes[i];
-        FillBuffer(buffer, 1.0f, size);
-        SampleUtil::copy3WithGain(buffer,
-                                  buffer, 1.0,
-                                  buffer, 1.0,
-                                  buffer, 1.0,
-                                  size);
-        AssertWholeBufferEquals(buffer, 3.0f, size);
-        SampleUtil::copy3WithGain(buffer,
-                                  buffer, 2.0,
-                                  buffer, 3.0,
-                                  buffer, 4.0,
-                                  size);
-        AssertWholeBufferEquals(buffer, 27.0f, size);
-    }
-}
-
 TEST_F(SampleUtilTest, convertS16ToFloat32) {
     // Shorts are asymmetric, so SAMPLE_MAX is less than -SAMPLE_MIN.
     const float expectedMax = static_cast<float>(SAMPLE_MAX) /
diff --git a/src/util/sample.cpp b/src/util/sample.cpp
index d657979773..ba79d67ab9 100644
--- a/src/util/sample.cpp
+++ b/src/util/sample.cpp
@@ -446,19 +446,37 @@ void SampleUtil::deinterleaveBuffer(CSAMPLE* M_RESTRICT pDest1,
 }
 
 // static
-void SampleUtil::linearCrossfadeBuffers(CSAMPLE* pDest,
-        const CSAMPLE* pSrcFadeOut, const CSAMPLE* pSrcFadeIn,
+void SampleUtil::linearCrossfadeBuffersOut(
+        CSAMPLE* pDestSrcFadeOut,
+        const CSAMPLE* pSrcFadeIn,
         SINT numSamples) {
+    // M_RESTRICT unoptimizes the function for some reason.
     const CSAMPLE_GAIN cross_inc = CSAMPLE_GAIN_ONE
             / CSAMPLE_GAIN(numSamples / 2);
     // note: LOOP VECTORIZED. only with "int i"
     for (int i = 0; i < numSamples / 2; ++i) {
         const CSAMPLE_GAIN cross_mix = cross_inc * i;
-        pDest[i * 2] = pSrcFadeIn[i * 2] * cross_mix
-                + pSrcFadeOut[i * 2] * (CSAMPLE_GAIN_ONE - cross_mix);
-        pDest[i * 2 + 1] = pSrcFadeIn[i * 2 + 1] * cross_mix
-                + pSrcFadeOut[i * 2 + 1] * (CSAMPLE_GAIN_ONE - cross_mix);
+        pDestSrcFadeOut[i * 2] *= (CSAMPLE_GAIN_ONE - cross_mix);
+        pDestSrcFadeOut[i * 2] += pSrcFadeIn[i * 2] * cross_mix;
+        pDestSrcFadeOut[i * 2 + 1] *= (CSAMPLE_GAIN_ONE - cross_mix);
+        pDestSrcFadeOut[i * 2 + 1] += pSrcFadeIn[i * 2 + 1] * cross_mix;
+    }
+}
 
+// static
+void SampleUtil::linearCrossfadeBuffersIn(
+        CSAMPLE* pDestSrcFadeIn,
+        const CSAMPLE* pSrcFadeOut,
+        SINT numSamples) {
+    // M_RESTRICT unoptimizes the function for some reason.
+    const CSAMPLE_GAIN cross_inc = CSAMPLE_GAIN_ONE / CSAMPLE_GAIN(numSamples / 2);
+    // note: LOOP VECTORIZED. only with "int i"
+    for (int i = 0; i < numSamples / 2; ++i) {
+        const CSAMPLE_GAIN cross_mix = cross_inc * i;
+        pDestSrcFadeIn[i * 2] *= cross_mix;
+        pDestSrcFadeIn[i * 2] += pSrcFadeOut[i * 2] * (CSAMPLE_GAIN_ONE - cross_mix);
+        pDestSrcFadeIn[i * 2 + 1] *= cross_mix;
+        pDestSrcFadeIn[i * 2 + 1] += pSrcFadeOut[i * 2 + 1] * (CSAMPLE_GAIN_ONE - cross_mix);
     }
 }
 
diff --git a/src/util/sample.h b/src/util/sample.h
index fbf5510fb1..4ccabe13c0 100644
--- a/src/util/sample.h
+++ b/src/util/sample.h
@@ -223,13 +223,12 @@ class SampleUtil {
     static void deinterleaveBuffer(CSAMPLE* pDest1, CSAMPLE* pDest2,
             const CSAMPLE* pSrc, SINT numSamples);
 
-    // Crossfade two buffers together and put the result in pDest.  All the
-    // buffers must be the same length.  pDest may be an alias of the source
-    // buffers.  It is preferable to use the copyWithRamping functions, but
-    // sometimes this function is necessary.
-    static void linearCrossfadeBuffers(CSAMPLE* pDest,
-            const CSAMPLE* pSrcFadeOut, const CSAMPLE* pSrcFadeIn,
-            SINT numSamples);
+    /// Crossfade two buffers together. All the buffers must be the same length.
+    /// pDest is in one version the Out and in the other version the In buffer.
+    static void linearCrossfadeBuffersOut(
+            CSAMPLE* pDestSrcFadeOut, const CSAMPLE* pSrcFadeIn, SINT numSamples);
+    static void linearCrossfadeBuffersIn(
+            CSAMPLE* pDestSrcFadeIn, const CSAMPLE* pSrcFadeOut, SINT numSamples);
 
     // Mix a buffer down to mono, putting the result in both of the channels.
     // This uses a simple (L+R)/2 method, which assumes that the audio is