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diff --git a/media/libopus/silk/fixed/find_LPC_FIX.c b/media/libopus/silk/fixed/find_LPC_FIX.c
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+/***********************************************************************
+Copyright (c) 2006-2011, Skype Limited. All rights reserved.
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+- Redistributions of source code must retain the above copyright notice,
+this list of conditions and the following disclaimer.
+- Redistributions in binary form must reproduce the above copyright
+notice, this list of conditions and the following disclaimer in the
+documentation and/or other materials provided with the distribution.
+- Neither the name of Internet Society, IETF or IETF Trust, nor the
+names of specific contributors, may be used to endorse or promote
+products derived from this software without specific prior written
+permission.
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+***********************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "main_FIX.h"
+#include "stack_alloc.h"
+#include "tuning_parameters.h"
+
+/* Finds LPC vector from correlations, and converts to NLSF */
+void silk_find_LPC_FIX(
+ silk_encoder_state *psEncC, /* I/O Encoder state */
+ opus_int16 NLSF_Q15[], /* O NLSFs */
+ const opus_int16 x[], /* I Input signal */
+ const opus_int32 minInvGain_Q30 /* I Inverse of max prediction gain */
+)
+{
+ opus_int k, subfr_length;
+ opus_int32 a_Q16[ MAX_LPC_ORDER ];
+ opus_int isInterpLower, shift;
+ opus_int32 res_nrg0, res_nrg1;
+ opus_int rshift0, rshift1;
+
+ /* Used only for LSF interpolation */
+ opus_int32 a_tmp_Q16[ MAX_LPC_ORDER ], res_nrg_interp, res_nrg, res_tmp_nrg;
+ opus_int res_nrg_interp_Q, res_nrg_Q, res_tmp_nrg_Q;
+ opus_int16 a_tmp_Q12[ MAX_LPC_ORDER ];
+ opus_int16 NLSF0_Q15[ MAX_LPC_ORDER ];
+ SAVE_STACK;
+
+ subfr_length = psEncC->subfr_length + psEncC->predictLPCOrder;
+
+ /* Default: no interpolation */
+ psEncC->indices.NLSFInterpCoef_Q2 = 4;
+
+ /* Burg AR analysis for the full frame */
+ silk_burg_modified( &res_nrg, &res_nrg_Q, a_Q16, x, minInvGain_Q30, subfr_length, psEncC->nb_subfr, psEncC->predictLPCOrder, psEncC->arch );
+
+ if( psEncC->useInterpolatedNLSFs && !psEncC->first_frame_after_reset && psEncC->nb_subfr == MAX_NB_SUBFR ) {
+ VARDECL( opus_int16, LPC_res );
+
+ /* Optimal solution for last 10 ms */
+ silk_burg_modified( &res_tmp_nrg, &res_tmp_nrg_Q, a_tmp_Q16, x + 2 * subfr_length, minInvGain_Q30, subfr_length, 2, psEncC->predictLPCOrder, psEncC->arch );
+
+ /* subtract residual energy here, as that's easier than adding it to the */
+ /* residual energy of the first 10 ms in each iteration of the search below */
+ shift = res_tmp_nrg_Q - res_nrg_Q;
+ if( shift >= 0 ) {
+ if( shift < 32 ) {
+ res_nrg = res_nrg - silk_RSHIFT( res_tmp_nrg, shift );
+ }
+ } else {
+ silk_assert( shift > -32 );
+ res_nrg = silk_RSHIFT( res_nrg, -shift ) - res_tmp_nrg;
+ res_nrg_Q = res_tmp_nrg_Q;
+ }
+
+ /* Convert to NLSFs */
+ silk_A2NLSF( NLSF_Q15, a_tmp_Q16, psEncC->predictLPCOrder );
+
+ ALLOC( LPC_res, 2 * subfr_length, opus_int16 );
+
+ /* Search over interpolation indices to find the one with lowest residual energy */
+ for( k = 3; k >= 0; k-- ) {
+ /* Interpolate NLSFs for first half */
+ silk_interpolate( NLSF0_Q15, psEncC->prev_NLSFq_Q15, NLSF_Q15, k, psEncC->predictLPCOrder );
+
+ /* Convert to LPC for residual energy evaluation */
+ silk_NLSF2A( a_tmp_Q12, NLSF0_Q15, psEncC->predictLPCOrder, psEncC->arch );
+
+ /* Calculate residual energy with NLSF interpolation */
+ silk_LPC_analysis_filter( LPC_res, x, a_tmp_Q12, 2 * subfr_length, psEncC->predictLPCOrder, psEncC->arch );
+
+ silk_sum_sqr_shift( &res_nrg0, &rshift0, LPC_res + psEncC->predictLPCOrder, subfr_length - psEncC->predictLPCOrder );
+ silk_sum_sqr_shift( &res_nrg1, &rshift1, LPC_res + psEncC->predictLPCOrder + subfr_length, subfr_length - psEncC->predictLPCOrder );
+
+ /* Add subframe energies from first half frame */
+ shift = rshift0 - rshift1;
+ if( shift >= 0 ) {
+ res_nrg1 = silk_RSHIFT( res_nrg1, shift );
+ res_nrg_interp_Q = -rshift0;
+ } else {
+ res_nrg0 = silk_RSHIFT( res_nrg0, -shift );
+ res_nrg_interp_Q = -rshift1;
+ }
+ res_nrg_interp = silk_ADD32( res_nrg0, res_nrg1 );
+
+ /* Compare with first half energy without NLSF interpolation, or best interpolated value so far */
+ shift = res_nrg_interp_Q - res_nrg_Q;
+ if( shift >= 0 ) {
+ if( silk_RSHIFT( res_nrg_interp, shift ) < res_nrg ) {
+ isInterpLower = silk_TRUE;
+ } else {
+ isInterpLower = silk_FALSE;
+ }
+ } else {
+ if( -shift < 32 ) {
+ if( res_nrg_interp < silk_RSHIFT( res_nrg, -shift ) ) {
+ isInterpLower = silk_TRUE;
+ } else {
+ isInterpLower = silk_FALSE;
+ }
+ } else {
+ isInterpLower = silk_FALSE;
+ }
+ }
+
+ /* Determine whether current interpolated NLSFs are best so far */
+ if( isInterpLower == silk_TRUE ) {
+ /* Interpolation has lower residual energy */
+ res_nrg = res_nrg_interp;
+ res_nrg_Q = res_nrg_interp_Q;
+ psEncC->indices.NLSFInterpCoef_Q2 = (opus_int8)k;
+ }
+ }
+ }
+
+ if( psEncC->indices.NLSFInterpCoef_Q2 == 4 ) {
+ /* NLSF interpolation is currently inactive, calculate NLSFs from full frame AR coefficients */
+ silk_A2NLSF( NLSF_Q15, a_Q16, psEncC->predictLPCOrder );
+ }
+
+ celt_assert( psEncC->indices.NLSFInterpCoef_Q2 == 4 || ( psEncC->useInterpolatedNLSFs && !psEncC->first_frame_after_reset && psEncC->nb_subfr == MAX_NB_SUBFR ) );
+ RESTORE_STACK;
+}