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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
+
+/* Insertion sort (fast for already almost sorted arrays): */
+/* Best case: O(n) for an already sorted array */
+/* Worst case: O(n^2) for an inversely sorted array */
+/* */
+/* Shell short: https://en.wikipedia.org/wiki/Shell_sort */
+
+#include "SigProc_FIX.h"
+
+void silk_insertion_sort_increasing(
+ opus_int32 *a, /* I/O Unsorted / Sorted vector */
+ opus_int *idx, /* O Index vector for the sorted elements */
+ const opus_int L, /* I Vector length */
+ const opus_int K /* I Number of correctly sorted positions */
+)
+{
+ opus_int32 value;
+ opus_int i, j;
+
+ /* Safety checks */
+ silk_assert( K > 0 );
+ silk_assert( L > 0 );
+ silk_assert( L >= K );
+
+ /* Write start indices in index vector */
+ for( i = 0; i < K; i++ ) {
+ idx[ i ] = i;
+ }
+
+ /* Sort vector elements by value, increasing order */
+ for( i = 1; i < K; i++ ) {
+ value = a[ i ];
+ for( j = i - 1; ( j >= 0 ) && ( value < a[ j ] ); j-- ) {
+ a[ j + 1 ] = a[ j ]; /* Shift value */
+ idx[ j + 1 ] = idx[ j ]; /* Shift index */
+ }
+ a[ j + 1 ] = value; /* Write value */
+ idx[ j + 1 ] = i; /* Write index */
+ }
+
+ /* If less than L values are asked for, check the remaining values, */
+ /* but only spend CPU to ensure that the K first values are correct */
+ for( i = K; i < L; i++ ) {
+ value = a[ i ];
+ if( value < a[ K - 1 ] ) {
+ for( j = K - 2; ( j >= 0 ) && ( value < a[ j ] ); j-- ) {
+ a[ j + 1 ] = a[ j ]; /* Shift value */
+ idx[ j + 1 ] = idx[ j ]; /* Shift index */
+ }
+ a[ j + 1 ] = value; /* Write value */
+ idx[ j + 1 ] = i; /* Write index */
+ }
+ }
+}
+
+#ifdef FIXED_POINT
+/* This function is only used by the fixed-point build */
+void silk_insertion_sort_decreasing_int16(
+ opus_int16 *a, /* I/O Unsorted / Sorted vector */
+ opus_int *idx, /* O Index vector for the sorted elements */
+ const opus_int L, /* I Vector length */
+ const opus_int K /* I Number of correctly sorted positions */
+)
+{
+ opus_int i, j;
+ opus_int value;
+
+ /* Safety checks */
+ silk_assert( K > 0 );
+ silk_assert( L > 0 );
+ silk_assert( L >= K );
+
+ /* Write start indices in index vector */
+ for( i = 0; i < K; i++ ) {
+ idx[ i ] = i;
+ }
+
+ /* Sort vector elements by value, decreasing order */
+ for( i = 1; i < K; i++ ) {
+ value = a[ i ];
+ for( j = i - 1; ( j >= 0 ) && ( value > a[ j ] ); j-- ) {
+ a[ j + 1 ] = a[ j ]; /* Shift value */
+ idx[ j + 1 ] = idx[ j ]; /* Shift index */
+ }
+ a[ j + 1 ] = value; /* Write value */
+ idx[ j + 1 ] = i; /* Write index */
+ }
+
+ /* If less than L values are asked for, check the remaining values, */
+ /* but only spend CPU to ensure that the K first values are correct */
+ for( i = K; i < L; i++ ) {
+ value = a[ i ];
+ if( value > a[ K - 1 ] ) {
+ for( j = K - 2; ( j >= 0 ) && ( value > a[ j ] ); j-- ) {
+ a[ j + 1 ] = a[ j ]; /* Shift value */
+ idx[ j + 1 ] = idx[ j ]; /* Shift index */
+ }
+ a[ j + 1 ] = value; /* Write value */
+ idx[ j + 1 ] = i; /* Write index */
+ }
+ }
+}
+#endif
+
+void silk_insertion_sort_increasing_all_values_int16(
+ opus_int16 *a, /* I/O Unsorted / Sorted vector */
+ const opus_int L /* I Vector length */
+)
+{
+ opus_int value;
+ opus_int i, j;
+
+ /* Safety checks */
+ silk_assert( L > 0 );
+
+ /* Sort vector elements by value, increasing order */
+ for( i = 1; i < L; i++ ) {
+ value = a[ i ];
+ for( j = i - 1; ( j >= 0 ) && ( value < a[ j ] ); j-- ) {
+ a[ j + 1 ] = a[ j ]; /* Shift value */
+ }
+ a[ j + 1 ] = value; /* Write value */
+ }
+}