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/*
* Copyright (c) 2011 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.
*/
/*
* This file contains the function WebRtcSpl_NormW32().
* The description header can be found in signal_processing_library.h
*
*/
#include "signal_processing_library.h"
#ifndef SPL_NO_DOUBLE_IMPLEMENTATIONS
int WebRtcSpl_NormW32(WebRtc_Word32 value)
{
int zeros = 0;
if (value <= 0)
value ^= 0xFFFFFFFF;
// Fast binary search to determine the number of left shifts required to 32-bit normalize
// the value
if (!(0xFFFF8000 & value))
zeros = 16;
if (!(0xFF800000 & (value << zeros)))
zeros += 8;
if (!(0xF8000000 & (value << zeros)))
zeros += 4;
if (!(0xE0000000 & (value << zeros)))
zeros += 2;
if (!(0xC0000000 & (value << zeros)))
zeros += 1;
return zeros;
}
#endif
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