Updating Opus to a pre-release of 1.1

silk/fixed/schur64_FIX.c

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@@ skipping 23 matching lines @@
     if( c[ 0 ] <= 0 ) {
         silk_memset( rc_Q16, 0, order * sizeof( opus_int32 ) );
         return 0;
     }
 
     for( k = 0; k < order + 1; k++ ) {
         C[ k ][ 0 ] = C[ k ][ 1 ] = c[ k ];
     }
 
     for( k = 0; k < order; k++ ) {
+        /* Check that we won't be getting an unstable rc, otherwise stop here. */
+        if (silk_abs_int32(C[ k + 1 ][ 0 ]) >= C[ 0 ][ 1 ]) {
+           if ( C[ k + 1 ][ 0 ] > 0 ) {
+              rc_Q16[ k ] = -SILK_FIX_CONST( .99f, 16 );
+           } else {
+              rc_Q16[ k ] = SILK_FIX_CONST( .99f, 16 );
+           }
+           k++;
+           break;
+        }
+
         /* Get reflection coefficient: divide two Q30 values and get result in Q31 */
         rc_tmp_Q31 = silk_DIV32_varQ( -C[ k + 1 ][ 0 ], C[ 0 ][ 1 ], 31 );
 
         /* Save the output */
         rc_Q16[ k ] = silk_RSHIFT_ROUND( rc_tmp_Q31, 15 );
 
         /* Update correlations */
         for( n = 0; n < order - k; n++ ) {
             Ctmp1_Q30 = C[ n + k + 1 ][ 0 ];
             Ctmp2_Q30 = C[ n ][ 1 ];
 
             /* Multiply and add the highest int32 */
             C[ n + k + 1 ][ 0 ] = Ctmp1_Q30 + silk_SMMUL( silk_LSHIFT( Ctmp2_Q30, 1 ), rc_tmp_Q31 );
             C[ n ][ 1 ]         = Ctmp2_Q30 + silk_SMMUL( silk_LSHIFT( Ctmp1_Q30, 1 ), rc_tmp_Q31 );
         }
     }
 
-    return( C[ 0 ][ 1 ] );
+    for(; k < order; k++ ) {
+       rc_Q16[ k ] = 0;
+    }
+
+    return silk_max_32( 1, C[ 0 ][ 1 ] );
 }