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  are permitted provided that the following conditions are met:
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  contributors, may be used to endorse or promote products derived from 
  this software without specific prior written permission.
  NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE GRANTED 
  BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
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  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  ***********************************************************************/
  
  #include "SKP_Silk_SigProc_FIX.h"
  
  /* Apply sine window to signal vector.                                      */
  /* Window types:                                                            */
  /*    1 -> sine window from 0 to pi/2                                       */
  /*    2 -> sine window from pi/2 to pi                                      */
  /* Every other sample is linearly interpolated, for speed.                  */
  /* Window length must be between 16 and 120 (incl) and a multiple of 4.     */
  
  /* Matlab code for table: 
     for k=16:9*4:16+2*9*4, fprintf(' %7.d,', -round(65536*pi ./ (k:4:k+8*4))); fprintf('\n'); end
  */
  static SKP_int16 freq_table_Q16[ 27 ] = {
     12111,    9804,    8235,    7100,    6239,    5565,    5022,    4575,    4202,
      3885,    3612,    3375,    3167,    2984,    2820,    2674,    2542,    2422,
      2313,    2214,    2123,    2038,    1961,    1889,    1822,    1760,    1702,
  };
  
  //#if EMBEDDED_ARM<6
  void SKP_Silk_apply_sine_window(
      SKP_int16                        px_win[],            /* O    Pointer to windowed signal                  */
      const SKP_int16                  px[],                /* I    Pointer to input signal                     */
      const SKP_int                    win_type,            /* I    Selects a window type                       */
      const SKP_int                    length               /* I    Window length, multiple of 4                */
  )
  {
      SKP_int   k, f_Q16, c_Q16;
      SKP_int32 S0_Q16, S1_Q16;
  #if !defined(_SYSTEM_IS_BIG_ENDIAN)
      SKP_int32 px32;
  #endif
      SKP_assert( win_type == 1 || win_type == 2 );
  
      /* Length must be in a range from 16 to 120 and a multiple of 4 */
      SKP_assert( length >= 16 && length <= 120 );
      SKP_assert( ( length & 3 ) == 0 );
  
      /* Input pointer must be 4-byte aligned */
      SKP_assert( ( ( SKP_int64 )( ( SKP_int8* )px - ( SKP_int8* )0 ) & 3 ) == 0 );
  
      /* Frequency */
      k = ( length >> 2 ) - 4;
      SKP_assert( k >= 0 && k <= 26 );
      f_Q16 = (SKP_int)freq_table_Q16[ k ];
  
      /* Factor used for cosine approximation */
      c_Q16 = SKP_SMULWB( f_Q16, -f_Q16 );
      SKP_assert( c_Q16 >= -32768 );
  
      /* initialize state */
      if( win_type == 1 ) {
          /* start from 0 */
          S0_Q16 = 0;
          /* approximation of sin(f) */
          S1_Q16 = f_Q16 + SKP_RSHIFT( length, 3 );
      } else {
          /* start from 1 */
          S0_Q16 = ( 1 << 16 );
          /* approximation of cos(f) */
          S1_Q16 = ( 1 << 16 ) + SKP_RSHIFT( c_Q16, 1 ) + SKP_RSHIFT( length, 4 );
      }
  
      /* Uses the recursive equation:   sin(n*f) = 2 * cos(f) * sin((n-1)*f) - sin((n-2)*f)    */
      /* 4 samples at a time */
  #if !defined(_SYSTEM_IS_BIG_ENDIAN)
      for( k = 0; k < length; k += 4 ) {
          px32 = *( (SKP_int32 *)&px[ k ] );                        /* load two values at once */
          px_win[ k ]     = (SKP_int16)SKP_SMULWB( SKP_RSHIFT( S0_Q16 + S1_Q16, 1 ), px32 );
          px_win[ k + 1 ] = (SKP_int16)SKP_SMULWT( S1_Q16, px32 );
          S0_Q16 = SKP_SMULWB( S1_Q16, c_Q16 ) + SKP_LSHIFT( S1_Q16, 1 ) - S0_Q16 + 1;
          S0_Q16 = SKP_min( S0_Q16, ( 1 << 16 ) );
  
          px32 = *( (SKP_int32 *)&px[k + 2] );                      /* load two values at once */
          px_win[ k + 2 ] = (SKP_int16)SKP_SMULWB( SKP_RSHIFT( S0_Q16 + S1_Q16, 1 ), px32 );
          px_win[ k + 3 ] = (SKP_int16)SKP_SMULWT( S0_Q16, px32 );
          S1_Q16 = SKP_SMULWB( S0_Q16, c_Q16 ) + SKP_LSHIFT( S0_Q16, 1 ) - S1_Q16;
          S1_Q16 = SKP_min( S1_Q16, ( 1 << 16 ) );
      }
  #else
      for( k = 0; k < length; k += 4 ) {
          px_win[ k ]     = (SKP_int16)SKP_SMULWB( SKP_RSHIFT( S0_Q16 + S1_Q16, 1 ), px[ k ] );
          px_win[ k + 1 ] = (SKP_int16)SKP_SMULWB( S1_Q16, px[ k + 1] );
          S0_Q16 = SKP_SMULWB( S1_Q16, c_Q16 ) + SKP_LSHIFT( S1_Q16, 1 ) - S0_Q16 + 1;
          S0_Q16 = SKP_min( S0_Q16, ( 1 << 16 ) );
  
          px_win[ k + 2 ] = (SKP_int16)SKP_SMULWB( SKP_RSHIFT( S0_Q16 + S1_Q16, 1 ), px[ k + 2] );
          px_win[ k + 3 ] = (SKP_int16)SKP_SMULWB( S0_Q16, px[ k + 3 ] );
          S1_Q16 = SKP_SMULWB( S0_Q16, c_Q16 ) + SKP_LSHIFT( S0_Q16, 1 ) - S1_Q16;
          S1_Q16 = SKP_min( S1_Q16, ( 1 << 16 ) );
      }
  #endif
  }
  //#endif
  