opus/silk/fixed/vector_ops_FIX.c

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#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "SigProc_FIX.h"

/* Copy and multiply a vector by a constant */
void silk_scale_copy_vector16(
    opus_int16                  *data_out,
    const opus_int16            *data_in,
    opus_int32                  gain_Q16,           /* I    Gain in Q16                                                 */
    const opus_int              dataSize            /* I    Length                                                      */
)
{
    opus_int  i;
    opus_int32 tmp32;

    for( i = 0; i < dataSize; i++ ) {
        tmp32 = silk_SMULWB( gain_Q16, data_in[ i ] );
        data_out[ i ] = (opus_int16)silk_CHECK_FIT16( tmp32 );
    }
}

/* Multiply a vector by a constant */
void silk_scale_vector32_Q26_lshift_18(
    opus_int32                  *data1,             /* I/O  Q0/Q18                                                      */
    opus_int32                  gain_Q26,           /* I    Q26                                                         */
    opus_int                    dataSize            /* I    length                                                      */
)
{
    opus_int  i;

    for( i = 0; i < dataSize; i++ ) {
        data1[ i ] = (opus_int32)silk_CHECK_FIT32( silk_RSHIFT64( silk_SMULL( data1[ i ], gain_Q26 ), 8 ) );    /* OUTPUT: Q18 */
    }
}

/* sum = for(i=0;i<len;i++)inVec1[i]*inVec2[i];      ---        inner product   */
/* Note for ARM asm:                                                            */
/*        * inVec1 and inVec2 should be at least 2 byte aligned.                */
/*        * len should be positive 16bit integer.                               */
/*        * only when len>6, memory access can be reduced by half.              */
opus_int32 silk_inner_prod_aligned(
    const opus_int16 *const     inVec1,             /*    I input vector 1                                              */
    const opus_int16 *const     inVec2,             /*    I input vector 2                                              */
    const opus_int              len                 /*    I vector lengths                                              */
)
{
    opus_int   i;
    opus_int32 sum = 0;
    for( i = 0; i < len; i++ ) {
        sum = silk_SMLABB( sum, inVec1[ i ], inVec2[ i ] );
    }
    return sum;
}

opus_int64 silk_inner_prod16_aligned_64(
    const opus_int16            *inVec1,            /*    I input vector 1                                              */
    const opus_int16            *inVec2,            /*    I input vector 2                                              */
    const opus_int              len                 /*    I vector lengths                                              */
)
{
    opus_int   i;
    opus_int64 sum = 0;
    for( i = 0; i < len; i++ ) {
        sum = silk_SMLALBB( sum, inVec1[ i ], inVec2[ i ] );
    }
    return sum;
}

/* Function that returns the maximum absolut value of the input vector */
opus_int16 silk_int16_array_maxabs(                 /* O   Maximum absolute value, max: 2^15-1                          */
    const opus_int16            *vec,               /* I   Input vector  [len]                                          */
    const opus_int32            len                 /* I   Length of input vector                                       */
)
{
    opus_int32 max = 0, i, lvl = 0, ind;
    if( len == 0 ) return 0;

    ind = len - 1;
    max = silk_SMULBB( vec[ ind ], vec[ ind ] );
    for( i = len - 2; i >= 0; i-- ) {
        lvl = silk_SMULBB( vec[ i ], vec[ i ] );
        if( lvl > max ) {
            max = lvl;
            ind = i;
        }
    }

    /* Do not return 32768, as it will not fit in an int16 so may lead to problems later on */
    if( max >= 1073676289 ) {           /* (2^15-1)^2 = 1073676289 */
        return( silk_int16_MAX );
    } else {
        if( vec[ ind ] < 0 ) {
            return( -vec[ ind ] );
        } else {
            return(  vec[ ind ] );
        }
    }
}