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 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 "A1 += R0.L*R1.H, A0 += R0.L*R1.L (IS) || R1.L = W[I1++];\n\t" 99 "A1 += R0.H*R1.L, A0 += R0.H*R1.H (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
