Tristan Matthews | 0a329cc | 2013-07-17 13:20:14 -0400 | [diff] [blame] | 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 | |