Commit 0025eaa5 authored by Sandesh Venkatesh's avatar Sandesh Venkatesh
Browse files

Merge branch '1366-improve-wmops-of-sns_1st_cod_fx' into 'main' 

Resolve "Improve WMOPS of sns_1st_cod_fx()"

Closes #1366

See merge request !1251
parents b9942967 149df281

lib_enc/ivas_sns_enc_fx.c

+186 −86
Original line number Diff line number Diff line
@@ -58,6 +58,105 @@ static Word16 sns_1st_cod_fx( 
    const Word16 core,

    Word32 *snsq_fx /* o  : quantized sns    Q16 */

)

{

    IF( exp_sns == Q15 )

    {

        Word16 index;

        const Word16 split_len = M / 2;

        move16();

        const Word16 *means;

        const Word16 means_fix = 2; // Q15

        move16();

        /* remove means */

        means = NULL;

        SWITCH( L_frame )

        {

            case L_FRAME16k:

                means = &sns_1st_means_16k[core - 1][0]; // Q14

                break;

            case L_FRAME25_6k:

                means = &sns_1st_means_25k6[core - 1][0]; // Q14

                break;

            case L_FRAME32k:

                means = &sns_1st_means_32k[core - 1][0]; // Q14

                break;

            default:

                assert( !"illegal frame length in sns_1st_cod" );

        }

        FOR( Word16 i = 0; i < M; ++i )

        {

            Word32 tmp = L_mult( means[i], means_fix ); // Q14->Q16

            snsq_fx[i] = L_sub( sns_fx[i], tmp );       // Q16

            move32();

        }



        index = 0;

        move16();

        FOR( Word16 split = 0; split < 2; ++split )

        {

            const Word16 *cdbk_ptr;

            Word16 j0, j1;

            Word16 index_split;

            Word32 dist_min_fx;

            const Word16 cdbk_fix = 8; // 1.f / powf( 2, SNS_CDBKS_BITS_4_FRAC ) in Q15

            move16();

            const Word16 *const cdbk = &sns_1st_cdbk[split][core - 1][0]; // Q12



            j0 = imult1616( split, split_len );

            j1 = add( j0, split_len );



            cdbk_ptr = cdbk;

            dist_min_fx = MAXVAL_WORD32;

            index_split = 0;

            move32();

            move16();

            FOR( Word16 i = 0; i < 32; ++i )

            {

                Word32 dist_fx = 0;

                move32();

                FOR( Word16 j = j0; j < j1; ++j ) // j1-j0=split_len. split_len=M/2. M=16

                {

                    Word32 tmp;

                    Word32 dist;



                    tmp = L_mult( *cdbk_ptr++, cdbk_fix ); // Q12->Q16

                    dist = L_sub( snsq_fx[j], tmp );       // Q16

                    dist = L_shl( dist, 11 );              // cdbk_ptr is a 16 bit LUT with 3.12 values, used as 3.16. assumption: snsq_fx has the same representation. thus, the subtraction results are in 4.16, which leaves 11 bit headroom.

                    dist = Mpy_32_32( dist, dist );

                    dist = L_shr( dist, 3 ); // make sure that the sum of 8 values does not overflow

                    dist_fx = L_add( dist_fx, dist );

                }



                IF( LT_32( dist_fx, dist_min_fx ) )

                {

                    dist_min_fx = dist_fx;

                    move32();

                    index_split = i;

                    move16();

                }

            }



            /* set quantized vector */

            cdbk_ptr = &cdbk[imult1616( index_split, split_len )];

            FOR( Word16 j = j0; j < j1; ++j )

            {

                Word32 tmp_3 = L_mult( means[j], means_fix );   // Q16

                Word32 tmp_4 = L_mult( *cdbk_ptr++, cdbk_fix ); // Q16

                snsq_fx[j] = L_add( tmp_4, tmp_3 );             // Q16

                move32();

            }



            /* for second split shift by five bits to store both indices as one 10 bit value */

            if ( EQ_16( split, 1 ) )

            {

                index_split = shl( index_split, 5 );

            }



            index = add( index, index_split );

        }

        return index;

    }

    ELSE

    {

        Word16 index, i;

        const Word16 split_len = M / 2;
@@ -169,6 +268,7 @@ static Word16 sns_1st_cod_fx( 


        return index;

    }

}



/*-------------------------------------------------------------------

 * sns_2st_cod()