Avoid left-shifting negative values in a number of places

webrtc/modules/audio_coding/neteq/expand.cc

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 694 matching lines @@
     //   voice_mix_factor = (-5179 + 19931x - 16422x^2 + 5776x^3) / 4096;
     // else
     //   voice_mix_factor = 0;
     if (corr_coefficient > 7875) {
       int16_t x1, x2, x3;
       // |corr_coefficient| is in Q14.
       x1 = static_cast<int16_t>(corr_coefficient);
       x2 = (x1 * x1) >> 14;   // Shift 14 to keep result in Q14.
       x3 = (x1 * x2) >> 14;
       static const int kCoefficients[4] = { -5179, 19931, -16422, 5776 };
-      int32_t temp_sum = kCoefficients[0] << 14;
+      int32_t temp_sum = kCoefficients[0] * 16384;
       temp_sum += kCoefficients[1] * x1;
       temp_sum += kCoefficients[2] * x2;
       temp_sum += kCoefficients[3] * x3;
       parameters.voice_mix_factor =
           static_cast<int16_t>(std::min(temp_sum / 4096, 16384));
       parameters.voice_mix_factor = std::max(parameters.voice_mix_factor,
                                              static_cast<int16_t>(0));
     } else {
       parameters.voice_mix_factor = 0;
     }
@@ skipping 18 matching lines @@
         parameters.mute_slope = (temp_ratio + 1) / 2;
       } else {
         // Divide by 8, with proper rounding.
         parameters.mute_slope = (temp_ratio + 4) / 8;
       }
       parameters.onset = true;
     } else {
       // Calculate (1 - slope) / distortion_lag.
       // Shift |slope| by 7 to Q20 before the division. The result is in Q20.
       parameters.mute_slope = WebRtcSpl_DivW32W16(
-          (8192 - slope) << 7, static_cast<int16_t>(distortion_lag));
+          (8192 - slope) * 128, static_cast<int16_t>(distortion_lag));
       if (parameters.voice_mix_factor <= 13107) {
         // Make sure the mute factor decreases from 1.0 to 0.9 in no more than
         // 6.25 ms.
         // mute_slope >= 0.005 / fs_mult in Q20.
         parameters.mute_slope = std::max(5243 / fs_mult, parameters.mute_slope);
       } else if (slope > 8028) {
         parameters.mute_slope = 0;
       }
       parameters.onset = false;
     }
@@ skipping 196 matching lines @@
   const size_t kMaxRandSamples = RandomVector::kRandomTableSize;
   while (samples_generated < length) {
     size_t rand_length = std::min(length - samples_generated, kMaxRandSamples);
     random_vector_->IncreaseSeedIncrement(seed_increment);
     random_vector_->Generate(rand_length, &random_vector[samples_generated]);
     samples_generated += rand_length;
   }
 }
 
 }  // namespace webrtc