/* Copyright (C) 2005 Analog Devices */
/**
@file lpc_bfin.h
@author Jean-Marc Valin
@brief Functions for LPC (Linear Prediction Coefficients) analysis (Blackfin version)
*/
/*
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``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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*/
#define OVERRIDE_SPEEX_AUTOCORR
void _spx_autocorr(
const spx_word16_t *x, /* in: [0...n-1] samples x */
spx_word16_t *ac, /* out: [0...lag-1] ac values */
int lag,
int n
)
{
spx_word32_t d;
const spx_word16_t *xs;
int i, j;
spx_word32_t ac0=1;
spx_word32_t ac32[11], *ac32top;
int shift, ac_shift;
ac32top = ac32+lag-1;
int lag_1, N_lag;
int nshift;
lag_1 = lag-1;
N_lag = n-lag_1;
for (j=0;j> 1;\n\t"
"LOOP_BEGIN pitch%=;\n\t"
"I1 = P0;\n\t"
"A1 = A0 = 0;\n\t"
"R1 = [I1++];\n\t"
"LOOP inner_prod%= LC1 = P3 >> 1;\n\t"
"LOOP_BEGIN inner_prod%=;\n\t"
"A1 += R0.L*R1.H, A0 += R0.L*R1.L (IS) || R1.L = W[I1++];\n\t"
"A1 += R0.H*R1.L, A0 += R0.H*R1.H (IS) || R1.H = W[I1++] || R0 = [I0++];\n\t"
"LOOP_END inner_prod%=;\n\t"
"A0 = ASHIFT A0 by R4.L;\n\t"
"A1 = ASHIFT A1 by R4.L;\n\t"
"R2 = A0, R3 = A1;\n\t"
"[P1--] = R2;\n\t"
"[P1--] = R3;\n\t"
"P0 += 4;\n\t"
"LOOP_END pitch%=;\n\t"
: : "m" (xs), "m" (x), "m" (ac32top), "m" (N_lag), "m" (lag_1), "m" (nshift)
: "A0", "A1", "P0", "P1", "P2", "P3", "P4", "R0", "R1", "R2", "R3", "R4", "I0", "I1", "L0", "L1", "B0", "B1", "memory"
);
d=0;
for (j=0;j