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#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include "main.h"

#include "stack_alloc.h"

#include "NSQ.h"

typedef struct {

    opus_int32 sLPC_Q14[ MAX_SUB_FRAME_LENGTH + NSQ_LPC_BUF_LENGTH ];

    opus_int32 RandState[ DECISION_DELAY ];

    opus_int32 Q_Q10[     DECISION_DELAY ];

    opus_int32 Xq_Q14[    DECISION_DELAY ];

    opus_int32 Pred_Q15[  DECISION_DELAY ];

    opus_int32 Shape_Q14[ DECISION_DELAY ];

    opus_int32 sAR2_Q14[ MAX_SHAPE_LPC_ORDER ];

    opus_int32 LF_AR_Q14;

    opus_int32 Diff_Q14;

    opus_int32 Seed;

    opus_int32 SeedInit;

    opus_int32 RD_Q10;

} NSQ_del_dec_struct;

typedef struct {

    opus_int32 Q_Q10;

    opus_int32 RD_Q10;

    opus_int32 xq_Q14;

    opus_int32 LF_AR_Q14;

    opus_int32 Diff_Q14;

    opus_int32 sLTP_shp_Q14;

    opus_int32 LPC_exc_Q14;

} NSQ_sample_struct;

typedef NSQ_sample_struct  NSQ_sample_pair[ 2 ];

#if defined(MIPSr1_ASM)

#include "mips/NSQ_del_dec_mipsr1.h"

#endif

static OPUS_INLINE void silk_nsq_del_dec_scale_states(

    const silk_encoder_state *psEncC,               /* I    Encoder State                       */

    silk_nsq_state      *NSQ,                       /* I/O  NSQ state                           */

    NSQ_del_dec_struct  psDelDec[],                 /* I/O  Delayed decision states             */

    const opus_int16    x16[],                      /* I    Input                               */

    opus_int32          x_sc_Q10[],                 /* O    Input scaled with 1/Gain in Q10     */

    const opus_int16    sLTP[],                     /* I    Re-whitened LTP state in Q0         */

    opus_int32          sLTP_Q15[],                 /* O    LTP state matching scaled input     */

    opus_int            subfr,                      /* I    Subframe number                     */

    opus_int            nStatesDelayedDecision,     /* I    Number of del dec states            */

    const opus_int      LTP_scale_Q14,              /* I    LTP state scaling                   */

    const opus_int32    Gains_Q16[ MAX_NB_SUBFR ],  /* I                                        */

    const opus_int      pitchL[ MAX_NB_SUBFR ],     /* I    Pitch lag                           */

    const opus_int      signal_type,                /* I    Signal type                         */

    const opus_int      decisionDelay               /* I    Decision delay                      */

);

/******************************************/

/* Noise shape quantizer for one subframe */

/******************************************/

static OPUS_INLINE void silk_noise_shape_quantizer_del_dec(

    silk_nsq_state      *NSQ,                   /* I/O  NSQ state                           */

    NSQ_del_dec_struct  psDelDec[],             /* I/O  Delayed decision states             */

    opus_int            signalType,             /* I    Signal type                         */

    const opus_int32    x_Q10[],                /* I                                        */

    opus_int8           pulses[],               /* O                                        */

    opus_int16          xq[],                   /* O                                        */

    opus_int32          sLTP_Q15[],             /* I/O  LTP filter state                    */

    opus_int32          delayedGain_Q10[],      /* I/O  Gain delay buffer                   */

    const opus_int16    a_Q12[],                /* I    Short term prediction coefs         */

    const opus_int16    b_Q14[],                /* I    Long term prediction coefs          */

    const opus_int16    AR_shp_Q13[],           /* I    Noise shaping coefs                 */

    opus_int            lag,                    /* I    Pitch lag                           */

    opus_int32          HarmShapeFIRPacked_Q14, /* I                                        */

    opus_int            Tilt_Q14,               /* I    Spectral tilt                       */

    opus_int32          LF_shp_Q14,             /* I                                        */

    opus_int32          Gain_Q16,               /* I                                        */

    opus_int            Lambda_Q10,             /* I                                        */

    opus_int            offset_Q10,             /* I                                        */

    opus_int            length,                 /* I    Input length                        */

    opus_int            subfr,                  /* I    Subframe number                     */

    opus_int            shapingLPCOrder,        /* I    Shaping LPC filter order            */

    opus_int            predictLPCOrder,        /* I    Prediction filter order             */

    opus_int            warping_Q16,            /* I                                        */

    opus_int            nStatesDelayedDecision, /* I    Number of states in decision tree   */

    opus_int            *smpl_buf_idx,          /* I/O  Index to newest samples in buffers  */

    opus_int            decisionDelay,          /* I                                        */

    int                 arch                    /* I                                        */

);

void silk_NSQ_del_dec_c(

    const silk_encoder_state    *psEncC,                                      /* I    Encoder State                   */

    silk_nsq_state              *NSQ,                                         /* I/O  NSQ state                       */

    SideInfoIndices             *psIndices,                                   /* I/O  Quantization Indices            */

    const opus_int16            x16[],                                        /* I    Input                           */

    opus_int8                   pulses[],                                     /* O    Quantized pulse signal          */

    const opus_int16            *PredCoef_Q12,                                /* I    Short term prediction coefs     */

    const opus_int16            LTPCoef_Q14[ LTP_ORDER * MAX_NB_SUBFR ],      /* I    Long term prediction coefs      */

    const opus_int16            AR_Q13[ MAX_NB_SUBFR * MAX_SHAPE_LPC_ORDER ], /* I    Noise shaping coefs             */

    const opus_int              HarmShapeGain_Q14[ MAX_NB_SUBFR ],            /* I    Long term shaping coefs         */

    const opus_int              Tilt_Q14[ MAX_NB_SUBFR ],                     /* I    Spectral tilt                   */

    const opus_int32            LF_shp_Q14[ MAX_NB_SUBFR ],                   /* I    Low frequency shaping coefs     */

    const opus_int32            Gains_Q16[ MAX_NB_SUBFR ],                    /* I    Quantization step sizes         */

    const opus_int              pitchL[ MAX_NB_SUBFR ],                       /* I    Pitch lags                      */

    const opus_int              Lambda_Q10,                                   /* I    Rate/distortion tradeoff        */

    const opus_int              LTP_scale_Q14                                 /* I    LTP state scaling               */

)

{

    opus_int            i, k, lag, start_idx, LSF_interpolation_flag, Winner_ind, subfr;

    opus_int            last_smple_idx, smpl_buf_idx, decisionDelay;

    const opus_int16    *A_Q12, *B_Q14, *AR_shp_Q13;

    opus_int16          *pxq;

    VARDECL( opus_int32, sLTP_Q15 );

    VARDECL( opus_int16, sLTP );

    opus_int32          HarmShapeFIRPacked_Q14;

    opus_int            offset_Q10;

    opus_int32          RDmin_Q10, Gain_Q10;

    VARDECL( opus_int32, x_sc_Q10 );

    VARDECL( opus_int32, delayedGain_Q10 );

    VARDECL( NSQ_del_dec_struct, psDelDec );

    NSQ_del_dec_struct  *psDD;

    SAVE_STACK;

    /* Set unvoiced lag to the previous one, overwrite later for voiced */

    lag = NSQ->lagPrev;

    silk_assert( NSQ->prev_gain_Q16 != 0 );

    /* Initialize delayed decision states */

    ALLOC( psDelDec, psEncC->nStatesDelayedDecision, NSQ_del_dec_struct );

    silk_memset( psDelDec, 0, psEncC->nStatesDelayedDecision * sizeof( NSQ_del_dec_struct ) );

    for( k = 0; k < psEncC->nStatesDelayedDecision; k++ ) {

        psDD                 = &psDelDec[ k ];

        psDD->Seed           = ( k + psIndices->Seed ) & 3;

        psDD->SeedInit       = psDD->Seed;

        psDD->RD_Q10         = 0;

        psDD->LF_AR_Q14      = NSQ->sLF_AR_shp_Q14;

        psDD->Diff_Q14       = NSQ->sDiff_shp_Q14;

        psDD->Shape_Q14[ 0 ] = NSQ->sLTP_shp_Q14[ psEncC->ltp_mem_length - 1 ];

        silk_memcpy( psDD->sLPC_Q14, NSQ->sLPC_Q14, NSQ_LPC_BUF_LENGTH * sizeof( opus_int32 ) );

        silk_memcpy( psDD->sAR2_Q14, NSQ->sAR2_Q14, sizeof( NSQ->sAR2_Q14 ) );

    }

    offset_Q10   = silk_Quantization_Offsets_Q10[ psIndices->signalType >> 1 ][ psIndices->quantOffsetType ];

    smpl_buf_idx = 0; /* index of oldest samples */

    decisionDelay = silk_min_int( DECISION_DELAY, psEncC->subfr_length );

    /* For voiced frames limit the decision delay to lower than the pitch lag */

    if( psIndices->signalType == TYPE_VOICED ) {

        for( k = 0; k < psEncC->nb_subfr; k++ ) {

            decisionDelay = silk_min_int( decisionDelay, pitchL[ k ] - LTP_ORDER / 2 - 1 );

        }

    } else {

        if( lag > 0 ) {

            decisionDelay = silk_min_int( decisionDelay, lag - LTP_ORDER / 2 - 1 );

        }

    }

    if( psIndices->NLSFInterpCoef_Q2 == 4 ) {

        LSF_interpolation_flag = 0;

    } else {

        LSF_interpolation_flag = 1;

    }

    ALLOC( sLTP_Q15, psEncC->ltp_mem_length + psEncC->frame_length, opus_int32 );

    ALLOC( sLTP, psEncC->ltp_mem_length + psEncC->frame_length, opus_int16 );

    ALLOC( x_sc_Q10, psEncC->subfr_length, opus_int32 );

    ALLOC( delayedGain_Q10, DECISION_DELAY, opus_int32 );

    /* Set up pointers to start of sub frame */

    pxq                   = &NSQ->xq[ psEncC->ltp_mem_length ];

    NSQ->sLTP_shp_buf_idx = psEncC->ltp_mem_length;

    NSQ->sLTP_buf_idx     = psEncC->ltp_mem_length;

    subfr = 0;

    for( k = 0; k < psEncC->nb_subfr; k++ ) {

        A_Q12      = &PredCoef_Q12[ ( ( k >> 1 ) | ( 1 - LSF_interpolation_flag ) ) * MAX_LPC_ORDER ];

        B_Q14      = &LTPCoef_Q14[ k * LTP_ORDER           ];

        AR_shp_Q13 = &AR_Q13[     k * MAX_SHAPE_LPC_ORDER ];

        /* Noise shape parameters */

        silk_assert( HarmShapeGain_Q14[ k ] >= 0 );

        HarmShapeFIRPacked_Q14  =                          silk_RSHIFT( HarmShapeGain_Q14[ k ], 2 );

        HarmShapeFIRPacked_Q14 |= silk_LSHIFT( (opus_int32)silk_RSHIFT( HarmShapeGain_Q14[ k ], 1 ), 16 );

        NSQ->rewhite_flag = 0;

        if( psIndices->signalType == TYPE_VOICED ) {

            /* Voiced */

            lag = pitchL[ k ];

            /* Re-whitening */

            if( ( k & ( 3 - silk_LSHIFT( LSF_interpolation_flag, 1 ) ) ) == 0 ) {

                if( k == 2 ) {

                    /* RESET DELAYED DECISIONS */

                    /* Find winner */

                    RDmin_Q10 = psDelDec[ 0 ].RD_Q10;

                    Winner_ind = 0;

                    for( i = 1; i < psEncC->nStatesDelayedDecision; i++ ) {

                        if( psDelDec[ i ].RD_Q10 < RDmin_Q10 ) {

                            RDmin_Q10 = psDelDec[ i ].RD_Q10;

                            Winner_ind = i;

                        }

                    }

                    for( i = 0; i < psEncC->nStatesDelayedDecision; i++ ) {

                        if( i != Winner_ind ) {

                            psDelDec[ i ].RD_Q10 += ( silk_int32_MAX >> 4 );

                            silk_assert( psDelDec[ i ].RD_Q10 >= 0 );

                        }

                    }

                    /* Copy final part of signals from winner state to output and long-term filter states */

                    psDD = &psDelDec[ Winner_ind ];

                    last_smple_idx = smpl_buf_idx + decisionDelay;

                    for( i = 0; i < decisionDelay; i++ ) {

                        last_smple_idx = ( last_smple_idx - 1 ) % DECISION_DELAY;

                        if( last_smple_idx < 0 ) last_smple_idx += DECISION_DELAY;

                        pulses[   i - decisionDelay ] = (opus_int8)silk_RSHIFT_ROUND( psDD->Q_Q10[ last_smple_idx ], 10 );

                        pxq[ i - decisionDelay ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND(

                            silk_SMULWW( psDD->Xq_Q14[ last_smple_idx ], Gains_Q16[ 1 ] ), 14 ) );

                        NSQ->sLTP_shp_Q14[ NSQ->sLTP_shp_buf_idx - decisionDelay + i ] = psDD->Shape_Q14[ last_smple_idx ];

                    }

                    subfr = 0;

                }

                /* Rewhiten with new A coefs */

                start_idx = psEncC->ltp_mem_length - lag - psEncC->predictLPCOrder - LTP_ORDER / 2;

                celt_assert( start_idx > 0 );

                silk_LPC_analysis_filter( &sLTP[ start_idx ], &NSQ->xq[ start_idx + k * psEncC->subfr_length ],

                    A_Q12, psEncC->ltp_mem_length - start_idx, psEncC->predictLPCOrder, psEncC->arch );

                NSQ->sLTP_buf_idx = psEncC->ltp_mem_length;

                NSQ->rewhite_flag = 1;

            }

        }

        silk_nsq_del_dec_scale_states( psEncC, NSQ, psDelDec, x16, x_sc_Q10, sLTP, sLTP_Q15, k,

            psEncC->nStatesDelayedDecision, LTP_scale_Q14, Gains_Q16, pitchL, psIndices->signalType, decisionDelay );

        silk_noise_shape_quantizer_del_dec( NSQ, psDelDec, psIndices->signalType, x_sc_Q10, pulses, pxq, sLTP_Q15,

            delayedGain_Q10, A_Q12, B_Q14, AR_shp_Q13, lag, HarmShapeFIRPacked_Q14, Tilt_Q14[ k ], LF_shp_Q14[ k ],

            Gains_Q16[ k ], Lambda_Q10, offset_Q10, psEncC->subfr_length, subfr++, psEncC->shapingLPCOrder,

            psEncC->predictLPCOrder, psEncC->warping_Q16, psEncC->nStatesDelayedDecision, &smpl_buf_idx, decisionDelay, psEncC->arch );

        x16    += psEncC->subfr_length;

        pulses += psEncC->subfr_length;

        pxq    += psEncC->subfr_length;

    }

    /* Find winner */

    RDmin_Q10 = psDelDec[ 0 ].RD_Q10;

    Winner_ind = 0;

    for( k = 1; k < psEncC->nStatesDelayedDecision; k++ ) {

        if( psDelDec[ k ].RD_Q10 < RDmin_Q10 ) {

            RDmin_Q10 = psDelDec[ k ].RD_Q10;

            Winner_ind = k;

        }

    }

    /* Copy final part of signals from winner state to output and long-term filter states */

    psDD = &psDelDec[ Winner_ind ];

    psIndices->Seed = psDD->SeedInit;

    last_smple_idx = smpl_buf_idx + decisionDelay;

    Gain_Q10 = silk_RSHIFT32( Gains_Q16[ psEncC->nb_subfr - 1 ], 6 );

    for( i = 0; i < decisionDelay; i++ ) {

        last_smple_idx = ( last_smple_idx - 1 ) % DECISION_DELAY;

        if( last_smple_idx < 0 ) last_smple_idx += DECISION_DELAY;

        pulses[   i - decisionDelay ] = (opus_int8)silk_RSHIFT_ROUND( psDD->Q_Q10[ last_smple_idx ], 10 );

        pxq[ i - decisionDelay ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND(

            silk_SMULWW( psDD->Xq_Q14[ last_smple_idx ], Gain_Q10 ), 8 ) );

        NSQ->sLTP_shp_Q14[ NSQ->sLTP_shp_buf_idx - decisionDelay + i ] = psDD->Shape_Q14[ last_smple_idx ];

    }

    silk_memcpy( NSQ->sLPC_Q14, &psDD->sLPC_Q14[ psEncC->subfr_length ], NSQ_LPC_BUF_LENGTH * sizeof( opus_int32 ) );

    silk_memcpy( NSQ->sAR2_Q14, psDD->sAR2_Q14, sizeof( psDD->sAR2_Q14 ) );

    /* Update states */

    NSQ->sLF_AR_shp_Q14 = psDD->LF_AR_Q14;

    NSQ->sDiff_shp_Q14  = psDD->Diff_Q14;

    NSQ->lagPrev        = pitchL[ psEncC->nb_subfr - 1 ];

    /* Save quantized speech signal */

    silk_memmove( NSQ->xq,           &NSQ->xq[           psEncC->frame_length ], psEncC->ltp_mem_length * sizeof( opus_int16 ) );

    silk_memmove( NSQ->sLTP_shp_Q14, &NSQ->sLTP_shp_Q14[ psEncC->frame_length ], psEncC->ltp_mem_length * sizeof( opus_int32 ) );

    RESTORE_STACK;

}

/******************************************/

/* Noise shape quantizer for one subframe */

/******************************************/

#ifndef OVERRIDE_silk_noise_shape_quantizer_del_dec

static OPUS_INLINE void silk_noise_shape_quantizer_del_dec(

    silk_nsq_state      *NSQ,                   /* I/O  NSQ state                           */

    NSQ_del_dec_struct  psDelDec[],             /* I/O  Delayed decision states             */

    opus_int            signalType,             /* I    Signal type                         */

    const opus_int32    x_Q10[],                /* I                                        */

    opus_int8           pulses[],               /* O                                        */

    opus_int16          xq[],                   /* O                                        */

    opus_int32          sLTP_Q15[],             /* I/O  LTP filter state                    */

    opus_int32          delayedGain_Q10[],      /* I/O  Gain delay buffer                   */

    const opus_int16    a_Q12[],                /* I    Short term prediction coefs         */

    const opus_int16    b_Q14[],                /* I    Long term prediction coefs          */

    const opus_int16    AR_shp_Q13[],           /* I    Noise shaping coefs                 */

    opus_int            lag,                    /* I    Pitch lag                           */

    opus_int32          HarmShapeFIRPacked_Q14, /* I                                        */

    opus_int            Tilt_Q14,               /* I    Spectral tilt                       */

    opus_int32          LF_shp_Q14,             /* I                                        */

    opus_int32          Gain_Q16,               /* I                                        */

    opus_int            Lambda_Q10,             /* I                                        */

    opus_int            offset_Q10,             /* I                                        */

    opus_int            length,                 /* I    Input length                        */

    opus_int            subfr,                  /* I    Subframe number                     */

    opus_int            shapingLPCOrder,        /* I    Shaping LPC filter order            */

    opus_int            predictLPCOrder,        /* I    Prediction filter order             */

    opus_int            warping_Q16,            /* I                                        */

    opus_int            nStatesDelayedDecision, /* I    Number of states in decision tree   */

    opus_int            *smpl_buf_idx,          /* I/O  Index to newest samples in buffers  */

    opus_int            decisionDelay,          /* I                                        */

    int                 arch                    /* I                                        */

)

{

    opus_int     i, j, k, Winner_ind, RDmin_ind, RDmax_ind, last_smple_idx;

    opus_int32   Winner_rand_state;

    opus_int32   LTP_pred_Q14, LPC_pred_Q14, n_AR_Q14, n_LTP_Q14;

    opus_int32   n_LF_Q14, r_Q10, rr_Q10, rd1_Q10, rd2_Q10, RDmin_Q10, RDmax_Q10;

    opus_int32   q1_Q0, q1_Q10, q2_Q10, exc_Q14, LPC_exc_Q14, xq_Q14, Gain_Q10;

    opus_int32   tmp1, tmp2, sLF_AR_shp_Q14;

    opus_int32   *pred_lag_ptr, *shp_lag_ptr, *psLPC_Q14;

#ifdef silk_short_prediction_create_arch_coef

    opus_int32   a_Q12_arch[MAX_LPC_ORDER];

#endif

    VARDECL( NSQ_sample_pair, psSampleState );

    NSQ_del_dec_struct *psDD;

    NSQ_sample_struct  *psSS;

    SAVE_STACK;

    celt_assert( nStatesDelayedDecision > 0 );

    ALLOC( psSampleState, nStatesDelayedDecision, NSQ_sample_pair );

    shp_lag_ptr  = &NSQ->sLTP_shp_Q14[ NSQ->sLTP_shp_buf_idx - lag + HARM_SHAPE_FIR_TAPS / 2 ];

    pred_lag_ptr = &sLTP_Q15[ NSQ->sLTP_buf_idx - lag + LTP_ORDER / 2 ];

    Gain_Q10     = silk_RSHIFT( Gain_Q16, 6 );

#ifdef silk_short_prediction_create_arch_coef

    silk_short_prediction_create_arch_coef(a_Q12_arch, a_Q12, predictLPCOrder);

#endif

    for( i = 0; i < length; i++ ) {

        /* Perform common calculations used in all states */

        /* Long-term prediction */

        if( signalType == TYPE_VOICED ) {

            /* Unrolled loop */

            /* Avoids introducing a bias because silk_SMLAWB() always rounds to -inf */

            LTP_pred_Q14 = 2;

            LTP_pred_Q14 = silk_SMLAWB( LTP_pred_Q14, pred_lag_ptr[  0 ], b_Q14[ 0 ] );

            LTP_pred_Q14 = silk_SMLAWB( LTP_pred_Q14, pred_lag_ptr[ -1 ], b_Q14[ 1 ] );

            LTP_pred_Q14 = silk_SMLAWB( LTP_pred_Q14, pred_lag_ptr[ -2 ], b_Q14[ 2 ] );

            LTP_pred_Q14 = silk_SMLAWB( LTP_pred_Q14, pred_lag_ptr[ -3 ], b_Q14[ 3 ] );

            LTP_pred_Q14 = silk_SMLAWB( LTP_pred_Q14, pred_lag_ptr[ -4 ], b_Q14[ 4 ] );

            LTP_pred_Q14 = silk_LSHIFT( LTP_pred_Q14, 1 );                          /* Q13 -> Q14 */

            pred_lag_ptr++;

        } else {

            LTP_pred_Q14 = 0;

        }

        /* Long-term shaping */

        if( lag > 0 ) {

            /* Symmetric, packed FIR coefficients */

            n_LTP_Q14 = silk_SMULWB( silk_ADD_SAT32( shp_lag_ptr[ 0 ], shp_lag_ptr[ -2 ] ), HarmShapeFIRPacked_Q14 );

            n_LTP_Q14 = silk_SMLAWT( n_LTP_Q14, shp_lag_ptr[ -1 ], HarmShapeFIRPacked_Q14 );

            n_LTP_Q14 = silk_SUB_LSHIFT32( LTP_pred_Q14, n_LTP_Q14, 2 );            /* Q12 -> Q14 */

            shp_lag_ptr++;

        } else {

            n_LTP_Q14 = 0;

        }

        for( k = 0; k < nStatesDelayedDecision; k++ ) {

            /* Delayed decision state */

            psDD = &psDelDec[ k ];

            /* Sample state */

            psSS = psSampleState[ k ];

            /* Generate dither */

            psDD->Seed = silk_RAND( psDD->Seed );

            /* Pointer used in short term prediction and shaping */

            psLPC_Q14 = &psDD->sLPC_Q14[ NSQ_LPC_BUF_LENGTH - 1 + i ];

            /* Short-term prediction */

            LPC_pred_Q14 = silk_noise_shape_quantizer_short_prediction(psLPC_Q14, a_Q12, a_Q12_arch, predictLPCOrder, arch);

            LPC_pred_Q14 = silk_LSHIFT( LPC_pred_Q14, 4 );                              /* Q10 -> Q14 */

            /* Noise shape feedback */

            celt_assert( ( shapingLPCOrder & 1 ) == 0 );   /* check that order is even */

            /* Output of lowpass section */

            tmp2 = silk_SMLAWB( psDD->Diff_Q14, psDD->sAR2_Q14[ 0 ], warping_Q16 );

            /* Output of allpass section */

            tmp1 = silk_SMLAWB( psDD->sAR2_Q14[ 0 ], silk_SUB32_ovflw(psDD->sAR2_Q14[ 1 ], tmp2), warping_Q16 );

            psDD->sAR2_Q14[ 0 ] = tmp2;

            n_AR_Q14 = silk_RSHIFT( shapingLPCOrder, 1 );

            n_AR_Q14 = silk_SMLAWB( n_AR_Q14, tmp2, AR_shp_Q13[ 0 ] );

            /* Loop over allpass sections */

            for( j = 2; j < shapingLPCOrder; j += 2 ) {

                /* Output of allpass section */

                tmp2 = silk_SMLAWB( psDD->sAR2_Q14[ j - 1 ], silk_SUB32_ovflw(psDD->sAR2_Q14[ j + 0 ], tmp1), warping_Q16 );

                psDD->sAR2_Q14[ j - 1 ] = tmp1;

                n_AR_Q14 = silk_SMLAWB( n_AR_Q14, tmp1, AR_shp_Q13[ j - 1 ] );

                /* Output of allpass section */

                tmp1 = silk_SMLAWB( psDD->sAR2_Q14[ j + 0 ], silk_SUB32_ovflw(psDD->sAR2_Q14[ j + 1 ], tmp2), warping_Q16 );

                psDD->sAR2_Q14[ j + 0 ] = tmp2;

                n_AR_Q14 = silk_SMLAWB( n_AR_Q14, tmp2, AR_shp_Q13[ j ] );

            }

            psDD->sAR2_Q14[ shapingLPCOrder - 1 ] = tmp1;

            n_AR_Q14 = silk_SMLAWB( n_AR_Q14, tmp1, AR_shp_Q13[ shapingLPCOrder - 1 ] );

            n_AR_Q14 = silk_LSHIFT( n_AR_Q14, 1 );                                      /* Q11 -> Q12 */

            n_AR_Q14 = silk_SMLAWB( n_AR_Q14, psDD->LF_AR_Q14, Tilt_Q14 );              /* Q12 */

            n_AR_Q14 = silk_LSHIFT( n_AR_Q14, 2 );                                      /* Q12 -> Q14 */

            n_LF_Q14 = silk_SMULWB( psDD->Shape_Q14[ *smpl_buf_idx ], LF_shp_Q14 );     /* Q12 */

            n_LF_Q14 = silk_SMLAWT( n_LF_Q14, psDD->LF_AR_Q14, LF_shp_Q14 );            /* Q12 */

            n_LF_Q14 = silk_LSHIFT( n_LF_Q14, 2 );                                      /* Q12 -> Q14 */

            /* Input minus prediction plus noise feedback                       */

            /* r = x[ i ] - LTP_pred - LPC_pred + n_AR + n_Tilt + n_LF + n_LTP  */

            tmp1 = silk_ADD_SAT32( n_AR_Q14, n_LF_Q14 );                                /* Q14 */

            tmp2 = silk_ADD32_ovflw( n_LTP_Q14, LPC_pred_Q14 );                         /* Q13 */

            tmp1 = silk_SUB_SAT32( tmp2, tmp1 );                                        /* Q13 */

            tmp1 = silk_RSHIFT_ROUND( tmp1, 4 );                                        /* Q10 */

            r_Q10 = silk_SUB32( x_Q10[ i ], tmp1 );                                     /* residual error Q10 */

            /* Flip sign depending on dither */

            if ( psDD->Seed < 0 ) {

                r_Q10 = -r_Q10;

            }

            r_Q10 = silk_LIMIT_32( r_Q10, -(31 << 10), 30 << 10 );

            /* Find two quantization level candidates and measure their rate-distortion */

            q1_Q10 = silk_SUB32( r_Q10, offset_Q10 );

            q1_Q0 = silk_RSHIFT( q1_Q10, 10 );

            if (Lambda_Q10 > 2048) {

                /* For aggressive RDO, the bias becomes more than one pulse. */

                int rdo_offset = Lambda_Q10/2 - 512;

                if (q1_Q10 > rdo_offset) {

                    q1_Q0 = silk_RSHIFT( q1_Q10 - rdo_offset, 10 );

                } else if (q1_Q10 < -rdo_offset) {

                    q1_Q0 = silk_RSHIFT( q1_Q10 + rdo_offset, 10 );

                } else if (q1_Q10 < 0) {

                    q1_Q0 = -1;

                } else {

                    q1_Q0 = 0;

                }

            }

            if( q1_Q0 > 0 ) {

                q1_Q10  = silk_SUB32( silk_LSHIFT( q1_Q0, 10 ), QUANT_LEVEL_ADJUST_Q10 );

                q1_Q10  = silk_ADD32( q1_Q10, offset_Q10 );

                q2_Q10  = silk_ADD32( q1_Q10, 1024 );

                rd1_Q10 = silk_SMULBB( q1_Q10, Lambda_Q10 );

                rd2_Q10 = silk_SMULBB( q2_Q10, Lambda_Q10 );

            } else if( q1_Q0 == 0 ) {

                q1_Q10  = offset_Q10;

                q2_Q10  = silk_ADD32( q1_Q10, 1024 - QUANT_LEVEL_ADJUST_Q10 );

                rd1_Q10 = silk_SMULBB( q1_Q10, Lambda_Q10 );

                rd2_Q10 = silk_SMULBB( q2_Q10, Lambda_Q10 );

            } else if( q1_Q0 == -1 ) {

                q2_Q10  = offset_Q10;

                q1_Q10  = silk_SUB32( q2_Q10, 1024 - QUANT_LEVEL_ADJUST_Q10 );

                rd1_Q10 = silk_SMULBB( -q1_Q10, Lambda_Q10 );

                rd2_Q10 = silk_SMULBB(  q2_Q10, Lambda_Q10 );

            } else {            /* q1_Q0 < -1 */

                q1_Q10  = silk_ADD32( silk_LSHIFT( q1_Q0, 10 ), QUANT_LEVEL_ADJUST_Q10 );

                q1_Q10  = silk_ADD32( q1_Q10, offset_Q10 );

                q2_Q10  = silk_ADD32( q1_Q10, 1024 );

                rd1_Q10 = silk_SMULBB( -q1_Q10, Lambda_Q10 );

                rd2_Q10 = silk_SMULBB( -q2_Q10, Lambda_Q10 );

            }

            rr_Q10  = silk_SUB32( r_Q10, q1_Q10 );

            rd1_Q10 = silk_RSHIFT( silk_SMLABB( rd1_Q10, rr_Q10, rr_Q10 ), 10 );

            rr_Q10  = silk_SUB32( r_Q10, q2_Q10 );

            rd2_Q10 = silk_RSHIFT( silk_SMLABB( rd2_Q10, rr_Q10, rr_Q10 ), 10 );

            if( rd1_Q10 < rd2_Q10 ) {

                psSS[ 0 ].RD_Q10 = silk_ADD32( psDD->RD_Q10, rd1_Q10 );

                psSS[ 1 ].RD_Q10 = silk_ADD32( psDD->RD_Q10, rd2_Q10 );

                psSS[ 0 ].Q_Q10  = q1_Q10;

                psSS[ 1 ].Q_Q10  = q2_Q10;

            } else {

                psSS[ 0 ].RD_Q10 = silk_ADD32( psDD->RD_Q10, rd2_Q10 );

                psSS[ 1 ].RD_Q10 = silk_ADD32( psDD->RD_Q10, rd1_Q10 );

                psSS[ 0 ].Q_Q10  = q2_Q10;

                psSS[ 1 ].Q_Q10  = q1_Q10;

            }

            /* Update states for best quantization */

            /* Quantized excitation */

            exc_Q14 = silk_LSHIFT32( psSS[ 0 ].Q_Q10, 4 );

            if ( psDD->Seed < 0 ) {

                exc_Q14 = -exc_Q14;

            }

            /* Add predictions */

            LPC_exc_Q14 = silk_ADD32( exc_Q14, LTP_pred_Q14 );

            xq_Q14      = silk_ADD32_ovflw( LPC_exc_Q14, LPC_pred_Q14 );

            /* Update states */

            psSS[ 0 ].Diff_Q14     = silk_SUB32_ovflw( xq_Q14, silk_LSHIFT32( x_Q10[ i ], 4 ) );

            sLF_AR_shp_Q14         = silk_SUB32_ovflw( psSS[ 0 ].Diff_Q14, n_AR_Q14 );

            psSS[ 0 ].sLTP_shp_Q14 = silk_SUB_SAT32( sLF_AR_shp_Q14, n_LF_Q14 );

            psSS[ 0 ].LF_AR_Q14    = sLF_AR_shp_Q14;

            psSS[ 0 ].LPC_exc_Q14  = LPC_exc_Q14;

            psSS[ 0 ].xq_Q14       = xq_Q14;

            /* Update states for second best quantization */

            /* Quantized excitation */

            exc_Q14 = silk_LSHIFT32( psSS[ 1 ].Q_Q10, 4 );

            if ( psDD->Seed < 0 ) {

                exc_Q14 = -exc_Q14;

            }

            /* Add predictions */

            LPC_exc_Q14 = silk_ADD32( exc_Q14, LTP_pred_Q14 );

            xq_Q14      = silk_ADD32_ovflw( LPC_exc_Q14, LPC_pred_Q14 );

            /* Update states */

            psSS[ 1 ].Diff_Q14     = silk_SUB32_ovflw( xq_Q14, silk_LSHIFT32( x_Q10[ i ], 4 ) );

            sLF_AR_shp_Q14         = silk_SUB32_ovflw( psSS[ 1 ].Diff_Q14, n_AR_Q14 );

            psSS[ 1 ].sLTP_shp_Q14 = silk_SUB_SAT32( sLF_AR_shp_Q14, n_LF_Q14 );

            psSS[ 1 ].LF_AR_Q14    = sLF_AR_shp_Q14;

            psSS[ 1 ].LPC_exc_Q14  = LPC_exc_Q14;

            psSS[ 1 ].xq_Q14       = xq_Q14;

        }

        *smpl_buf_idx  = ( *smpl_buf_idx - 1 ) % DECISION_DELAY;

        if( *smpl_buf_idx < 0 ) *smpl_buf_idx += DECISION_DELAY;

        last_smple_idx = ( *smpl_buf_idx + decisionDelay ) % DECISION_DELAY;

        /* Find winner */

        RDmin_Q10 = psSampleState[ 0 ][ 0 ].RD_Q10;

        Winner_ind = 0;

        for( k = 1; k < nStatesDelayedDecision; k++ ) {

            if( psSampleState[ k ][ 0 ].RD_Q10 < RDmin_Q10 ) {

                RDmin_Q10  = psSampleState[ k ][ 0 ].RD_Q10;

                Winner_ind = k;

            }

        }

        /* Increase RD values of expired states */

        Winner_rand_state = psDelDec[ Winner_ind ].RandState[ last_smple_idx ];

        for( k = 0; k < nStatesDelayedDecision; k++ ) {

            if( psDelDec[ k ].RandState[ last_smple_idx ] != Winner_rand_state ) {

                psSampleState[ k ][ 0 ].RD_Q10 = silk_ADD32( psSampleState[ k ][ 0 ].RD_Q10, silk_int32_MAX >> 4 );

                psSampleState[ k ][ 1 ].RD_Q10 = silk_ADD32( psSampleState[ k ][ 1 ].RD_Q10, silk_int32_MAX >> 4 );

                silk_assert( psSampleState[ k ][ 0 ].RD_Q10 >= 0 );

            }

        }

        /* Find worst in first set and best in second set */

        RDmax_Q10  = psSampleState[ 0 ][ 0 ].RD_Q10;

        RDmin_Q10  = psSampleState[ 0 ][ 1 ].RD_Q10;

        RDmax_ind = 0;

        RDmin_ind = 0;

        for( k = 1; k < nStatesDelayedDecision; k++ ) {

            /* find worst in first set */

            if( psSampleState[ k ][ 0 ].RD_Q10 > RDmax_Q10 ) {

                RDmax_Q10  = psSampleState[ k ][ 0 ].RD_Q10;

                RDmax_ind = k;

            }

            /* find best in second set */

            if( psSampleState[ k ][ 1 ].RD_Q10 < RDmin_Q10 ) {

                RDmin_Q10  = psSampleState[ k ][ 1 ].RD_Q10;

                RDmin_ind = k;

            }

        }

        /* Replace a state if best from second set outperforms worst in first set */

        if( RDmin_Q10 < RDmax_Q10 ) {

            silk_memcpy( ( (opus_int32 *)&psDelDec[ RDmax_ind ] ) + i,

                         ( (opus_int32 *)&psDelDec[ RDmin_ind ] ) + i, sizeof( NSQ_del_dec_struct ) - i * sizeof( opus_int32) );

            silk_memcpy( &psSampleState[ RDmax_ind ][ 0 ], &psSampleState[ RDmin_ind ][ 1 ], sizeof( NSQ_sample_struct ) );

        }

        /* Write samples from winner to output and long-term filter states */

        psDD = &psDelDec[ Winner_ind ];

        if( subfr > 0 || i >= decisionDelay ) {

            pulses[  i - decisionDelay ] = (opus_int8)silk_RSHIFT_ROUND( psDD->Q_Q10[ last_smple_idx ], 10 );

            xq[ i - decisionDelay ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND(

                silk_SMULWW( psDD->Xq_Q14[ last_smple_idx ], delayedGain_Q10[ last_smple_idx ] ), 8 ) );

            NSQ->sLTP_shp_Q14[ NSQ->sLTP_shp_buf_idx - decisionDelay ] = psDD->Shape_Q14[ last_smple_idx ];

            sLTP_Q15[          NSQ->sLTP_buf_idx     - decisionDelay ] = psDD->Pred_Q15[  last_smple_idx ];

        }

        NSQ->sLTP_shp_buf_idx++;

        NSQ->sLTP_buf_idx++;

        /* Update states */

        for( k = 0; k < nStatesDelayedDecision; k++ ) {

            psDD                                     = &psDelDec[ k ];

            psSS                                     = &psSampleState[ k ][ 0 ];

            psDD->LF_AR_Q14                          = psSS->LF_AR_Q14;

            psDD->Diff_Q14                           = psSS->Diff_Q14;

            psDD->sLPC_Q14[ NSQ_LPC_BUF_LENGTH + i ] = psSS->xq_Q14;

            psDD->Xq_Q14[    *smpl_buf_idx ]         = psSS->xq_Q14;

            psDD->Q_Q10[     *smpl_buf_idx ]         = psSS->Q_Q10;

            psDD->Pred_Q15[  *smpl_buf_idx ]         = silk_LSHIFT32( psSS->LPC_exc_Q14, 1 );

            psDD->Shape_Q14[ *smpl_buf_idx ]         = psSS->sLTP_shp_Q14;

            psDD->Seed                               = silk_ADD32_ovflw( psDD->Seed, silk_RSHIFT_ROUND( psSS->Q_Q10, 10 ) );

            psDD->RandState[ *smpl_buf_idx ]         = psDD->Seed;

            psDD->RD_Q10                             = psSS->RD_Q10;

        }

        delayedGain_Q10[     *smpl_buf_idx ]         = Gain_Q10;

    }

    /* Update LPC states */

    for( k = 0; k < nStatesDelayedDecision; k++ ) {

        psDD = &psDelDec[ k ];

        silk_memcpy( psDD->sLPC_Q14, &psDD->sLPC_Q14[ length ], NSQ_LPC_BUF_LENGTH * sizeof( opus_int32 ) );

    }

    RESTORE_STACK;

}

#endif /* OVERRIDE_silk_noise_shape_quantizer_del_dec */

static OPUS_INLINE void silk_nsq_del_dec_scale_states(

    const silk_encoder_state *psEncC,               /* I    Encoder State                       */

    silk_nsq_state      *NSQ,                       /* I/O  NSQ state                           */

    NSQ_del_dec_struct  psDelDec[],                 /* I/O  Delayed decision states             */

    const opus_int16    x16[],                      /* I    Input                               */

    opus_int32          x_sc_Q10[],                 /* O    Input scaled with 1/Gain in Q10     */

    const opus_int16    sLTP[],                     /* I    Re-whitened LTP state in Q0         */

    opus_int32          sLTP_Q15[],                 /* O    LTP state matching scaled input     */

    opus_int            subfr,                      /* I    Subframe number                     */

    opus_int            nStatesDelayedDecision,     /* I    Number of del dec states            */

    const opus_int      LTP_scale_Q14,              /* I    LTP state scaling                   */

    const opus_int32    Gains_Q16[ MAX_NB_SUBFR ],  /* I                                        */

    const opus_int      pitchL[ MAX_NB_SUBFR ],     /* I    Pitch lag                           */

    const opus_int      signal_type,                /* I    Signal type                         */

    const opus_int      decisionDelay               /* I    Decision delay                      */

)

{

    opus_int            i, k, lag;

    opus_int32          gain_adj_Q16, inv_gain_Q31, inv_gain_Q26;

    NSQ_del_dec_struct  *psDD;

    lag          = pitchL[ subfr ];

    inv_gain_Q31 = silk_INVERSE32_varQ( silk_max( Gains_Q16[ subfr ], 1 ), 47 );

    silk_assert( inv_gain_Q31 != 0 );

    /* Scale input */

    inv_gain_Q26 = silk_RSHIFT_ROUND( inv_gain_Q31, 5 );

    for( i = 0; i < psEncC->subfr_length; i++ ) {

        x_sc_Q10[ i ] = silk_SMULWW( x16[ i ], inv_gain_Q26 );

    }

    /* After rewhitening the LTP state is un-scaled, so scale with inv_gain_Q16 */

    if( NSQ->rewhite_flag ) {

        if( subfr == 0 ) {

            /* Do LTP downscaling */

            inv_gain_Q31 = silk_LSHIFT( silk_SMULWB( inv_gain_Q31, LTP_scale_Q14 ), 2 );

        }

        for( i = NSQ->sLTP_buf_idx - lag - LTP_ORDER / 2; i < NSQ->sLTP_buf_idx; i++ ) {

            silk_assert( i < MAX_FRAME_LENGTH );

            sLTP_Q15[ i ] = silk_SMULWB( inv_gain_Q31, sLTP[ i ] );

        }

    }

    /* Adjust for changing gain */

    if( Gains_Q16[ subfr ] != NSQ->prev_gain_Q16 ) {

        gain_adj_Q16 =  silk_DIV32_varQ( NSQ->prev_gain_Q16, Gains_Q16[ subfr ], 16 );

        /* Scale long-term shaping state */

        for( i = NSQ->sLTP_shp_buf_idx - psEncC->ltp_mem_length; i < NSQ->sLTP_shp_buf_idx; i++ ) {

            NSQ->sLTP_shp_Q14[ i ] = silk_SMULWW( gain_adj_Q16, NSQ->sLTP_shp_Q14[ i ] );

        }

        /* Scale long-term prediction state */

        if( signal_type == TYPE_VOICED && NSQ->rewhite_flag == 0 ) {

            for( i = NSQ->sLTP_buf_idx - lag - LTP_ORDER / 2; i < NSQ->sLTP_buf_idx - decisionDelay; i++ ) {

                sLTP_Q15[ i ] = silk_SMULWW( gain_adj_Q16, sLTP_Q15[ i ] );

            }

        }

        for( k = 0; k < nStatesDelayedDecision; k++ ) {

            psDD = &psDelDec[ k ];

            /* Scale scalar states */

            psDD->LF_AR_Q14 = silk_SMULWW( gain_adj_Q16, psDD->LF_AR_Q14 );

            psDD->Diff_Q14 = silk_SMULWW( gain_adj_Q16, psDD->Diff_Q14 );

            /* Scale short-term prediction and shaping states */

            for( i = 0; i < NSQ_LPC_BUF_LENGTH; i++ ) {

                psDD->sLPC_Q14[ i ] = silk_SMULWW( gain_adj_Q16, psDD->sLPC_Q14[ i ] );

            }

            for( i = 0; i < MAX_SHAPE_LPC_ORDER; i++ ) {

                psDD->sAR2_Q14[ i ] = silk_SMULWW( gain_adj_Q16, psDD->sAR2_Q14[ i ] );

            }

            for( i = 0; i < DECISION_DELAY; i++ ) {

                psDD->Pred_Q15[  i ] = silk_SMULWW( gain_adj_Q16, psDD->Pred_Q15[  i ] );

                psDD->Shape_Q14[ i ] = silk_SMULWW( gain_adj_Q16, psDD->Shape_Q14[ i ] );

            }

        }

        /* Save inverse gain */

        NSQ->prev_gain_Q16 = Gains_Q16[ subfr ];

    }

}