ref: fbed746cb2d0fee57eae090e67d148d89923f6ff
dir: /silk/tests/test_unit_LPC_inv_pred_gain.c/
/*********************************************************************** Copyright (c) 2017 Google Inc., Jean-Marc Valin 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 <stdio.h> #include <stdlib.h> #include "celt/stack_alloc.h" #include "cpu_support.h" #include "SigProc_FIX.h" /* Computes the impulse response of the filter so we can catch filters that are definitely unstable. Some unstable filters may be classified as stable, but not the other way around. */ int check_stability(opus_int16 *A_Q12, int order) { int i; int j; int sum_a, sum_abs_a; double y[SILK_MAX_ORDER_LPC] = {0}; sum_a = sum_abs_a = 0; for( j = 0; j < order; j++ ) { sum_a += A_Q12[ j ]; sum_abs_a += silk_abs( A_Q12[ j ] ); } /* Check DC stability. */ if( sum_a >= 4096 ) { return 0; } /* If the sum of absolute values is less than 1, the filter has to be stable. */ if( sum_abs_a < 4096 ) { return 1; } y[0] = 1; for( i = 0; i < 10000; i++ ) { double sum = 0; for( j = 0; j < order; j++ ) { sum += y[ j ]*A_Q12[ j ]; } for( j = order - 1; j > 0; j-- ) { y[ j ] = y[ j - 1 ]; } y[ 0 ] = sum*(1./4096); /* If impulse response reaches +/- 10000, the filter is definitely unstable. */ if( !(y[ 0 ] < 10000 && y[ 0 ] > -10000) ) { return 0; } /* Test every 8 sample for low amplitude. */ if( ( i & 0x7 ) == 0 ) { double amp = 0; for( j = 0; j < order; j++ ) { amp += fabs(y[j]); } if( amp < 0.00001 ) { return 1; } } } return 1; } int main(void) { const int arch = opus_select_arch(); /* Set to 10000 so all branches in C function are triggered */ const int loop_num = 10000; int count = 0; ALLOC_STACK; /* FIXME: Make the seed random (with option to set it explicitly) so we get wider coverage. */ srand(0); printf("Testing silk_LPC_inverse_pred_gain() optimization ...\n"); for( count = 0; count < loop_num; count++ ) { unsigned int i; opus_int order; unsigned int shift; opus_int16 A_Q12[ SILK_MAX_ORDER_LPC ]; opus_int32 gain; for( order = 2; order <= SILK_MAX_ORDER_LPC; order += 2 ) { /* order must be even. */ for( shift = 0; shift < 16; shift++ ) { /* Different dynamic range. */ for( i = 0; i < SILK_MAX_ORDER_LPC; i++ ) { A_Q12[i] = ((opus_int16)rand()) >> shift; } gain = silk_LPC_inverse_pred_gain(A_Q12, order, arch); /* Look for filters that silk_LPC_inverse_pred_gain() thinks are stable but definitely aren't. */ if( gain != 0 && !check_stability(A_Q12, order) ) { fprintf(stderr, "**Loop %4d failed!**\n", count); return 1; } } } if( !(count % 500) ) { printf("Loop %4d passed\n", count); } } printf("silk_LPC_inverse_pred_gain() optimization passed\n"); return 0; }