Remove redundancies of multiply() in FFTFrame.

Source/platform/audio/FFTFrame.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 14 matching lines @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 
 #if ENABLE(WEB_AUDIO)
 
 #include "platform/audio/FFTFrame.h"
 
+#include "platform/audio/VectorMath.h"
+
 #ifndef NDEBUG
 #include <stdio.h>
 #endif
 
 #include "platform/Logging.h"
 #include "wtf/Complex.h"
 #include "wtf/MathExtras.h"
 #include "wtf/OwnPtr.h"
 
 namespace WebCore {
@@ skipping 207 matching lines @@
 
         phase += i * phaseAdj;
 
         Complex c2 = complexFromMagnitudePhase(mag, phase);
 
         realP[i] = static_cast<float>(c2.real());
         imagP[i] = static_cast<float>(c2.imag());
     }
 }
 
+void FFTFrame::multiply(const FFTFrame& frame)
+{
+    FFTFrame& frame1 = *this;
+    FFTFrame& frame2 = const_cast<FFTFrame&>(frame);
+
+    float* realP1 = frame1.realData();
+    float* imagP1 = frame1.imagData();
+    const float* realP2 = frame2.realData();
+    const float* imagP2 = frame2.imagData();
+
+    unsigned halfSize = fftSize() / 2;
+    float real0 = realP1[0];
+    float imag0 = imagP1[0];
+
+    VectorMath::zvmul(realP1, imagP1, realP2, imagP2, realP1, imagP1, halfSize);
+
+    // Multiply the packed DC/nyquist component
+    realP1[0] = real0 * realP2[0];
+    imagP1[0] = imag0 * imagP2[0];
+}
+
 #ifndef NDEBUG
 void FFTFrame::print()
 {
     FFTFrame& frame = *this;
     float* realP = frame.realData();
     float* imagP = frame.imagData();
     WTF_LOG(WebAudio, "**** \n");
     WTF_LOG(WebAudio, "DC = %f : nyquist = %f\n", realP[0], imagP[0]);
 
     int n = m_FFTSize / 2;
 
     for (int i = 1; i < n; i++) {
         double mag = sqrt(realP[i] * realP[i] + imagP[i] * imagP[i]);
         double phase = atan2(realP[i], imagP[i]);
 
         WTF_LOG(WebAudio, "[%d] (%f %f)\n", i, mag, phase);
     }
     WTF_LOG(WebAudio, "****\n");
 }
 #endif // NDEBUG
 
 } // namespace WebCore
 
 #endif // ENABLE(WEB_AUDIO)