1 /* Copyright (C) 2005 Analog Devices */
2 /**
3 @file lpc_bfin.h
4 @author Jean-Marc Valin
5 @brief Functions for LPC (Linear Prediction Coefficients) analysis (Blackfin version)
6 */
7 /*
8 Redistribution and use in source and binary forms, with or without
9 modification, are permitted provided that the following conditions
10 are met:
11
12 - Redistributions of source code must retain the above copyright
13 notice, this list of conditions and the following disclaimer.
14
15 - Redistributions in binary form must reproduce the above copyright
16 notice, this list of conditions and the following disclaimer in the
17 documentation and/or other materials provided with the distribution.
18
19 - Neither the name of the Xiph.org Foundation nor the names of its
20 contributors may be used to endorse or promote products derived from
21 this software without specific prior written permission.
22
23 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26 A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
27 CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
28 EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
29 PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31 LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 #define OVERRIDE_SPEEX_AUTOCORR
_spx_autocorr(const spx_word16_t * x,spx_word16_t * ac,int lag,int n)37 void _spx_autocorr(
38 const spx_word16_t *x, /* in: [0...n-1] samples x */
39 spx_word16_t *ac, /* out: [0...lag-1] ac values */
40 int lag,
41 int n
42 )
43 {
44 spx_word32_t d;
45 const spx_word16_t *xs;
46 int i, j;
47 spx_word32_t ac0=1;
48 spx_word32_t ac32[11], *ac32top;
49 int shift, ac_shift;
50 ac32top = ac32+lag-1;
51 int lag_1, N_lag;
52 int nshift;
53 lag_1 = lag-1;
54 N_lag = n-lag_1;
55 for (j=0;j<n;j++)
56 ac0 = ADD32(ac0,SHR32(MULT16_16(x[j],x[j]),8));
57 ac0 = ADD32(ac0,n);
58 shift = 8;
59 while (shift && ac0<0x40000000)
60 {
61 shift--;
62 ac0 <<= 1;
63 }
64 ac_shift = 18;
65 while (ac_shift && ac0<0x40000000)
66 {
67 ac_shift--;
68 ac0 <<= 1;
69 }
70
71 xs = x+lag-1;
72 nshift = -shift;
73 __asm__ __volatile__
74 (
75 "P2 = %0;\n\t"
76 "I0 = P2;\n\t" /* x in I0 */
77 "B0 = P2;\n\t" /* x in B0 */
78 "R0 = %3;\n\t" /* len in R0 */
79 "P3 = %3;\n\t" /* len in R0 */
80 "P4 = %4;\n\t" /* nb_pitch in R0 */
81 "R1 = R0 << 1;\n\t" /* number of bytes in x */
82 "L0 = R1;\n\t"
83 "P0 = %1;\n\t"
84 "P1 = %2;\n\t"
85 "B1 = P1;\n\t"
86 "R4 = %5;\n\t"
87 "L1 = 0;\n\t" /*Disable looping on I1*/
88
89 "r0 = [I0++];\n\t"
90 "R2 = 0;R3=0;"
91 "LOOP pitch%= LC0 = P4 >> 1;\n\t"
92 "LOOP_BEGIN pitch%=;\n\t"
93 "I1 = P0;\n\t"
94 "A1 = A0 = 0;\n\t"
95 "R1 = [I1++];\n\t"
96 "LOOP inner_prod%= LC1 = P3 >> 1;\n\t"
97 "LOOP_BEGIN inner_prod%=;\n\t"
98 "A0 += R0.L*R1.L , A1 += R0.L*R1.H (is) || R1.L = W[I1++];\n\t"
99 "A0 += R0.H*R1.H , A1 += R0.H*R1.L (is) || R1.H = W[I1++] || R0 = [I0++];\n\t"
100 "LOOP_END inner_prod%=;\n\t"
101 "A0 = ASHIFT A0 by R4.L;\n\t"
102 "A1 = ASHIFT A1 by R4.L;\n\t"
103
104 "R2 = A0, R3 = A1;\n\t"
105 "[P1--] = R2;\n\t"
106 "[P1--] = R3;\n\t"
107 "P0 += 4;\n\t"
108 "LOOP_END pitch%=;\n\t"
109 : : "m" (xs), "m" (x), "m" (ac32top), "m" (N_lag), "m" (lag_1), "m" (nshift)
110 : "A0", "A1", "P0", "P1", "P2", "P3", "P4", "R0", "R1", "R2", "R3", "R4", "I0", "I1", "L0", "L1", "B0", "B1", "memory"
111 );
112 d=0;
113 for (j=0;j<n;j++)
114 {
115 d = ADD32(d,SHR32(MULT16_16(x[j],x[j]), shift));
116 }
117 ac32[0] = d;
118
119 for (i=0;i<lag;i++)
120 {
121 d=0;
122 for (j=i;j<lag_1;j++)
123 {
124 d = ADD32(d,SHR32(MULT16_16(x[j],x[j-i]), shift));
125 }
126 if (i)
127 ac32[i] += d;
128 ac[i] = SHR32(ac32[i], ac_shift);
129 }
130 }
131
132