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Diffstat (limited to 'benchmarks/CHStone/gsm/lpc.c')
| -rwxr-xr-x | benchmarks/CHStone/gsm/lpc.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/benchmarks/CHStone/gsm/lpc.c b/benchmarks/CHStone/gsm/lpc.c new file mode 100755 index 0000000..d70ab0e --- /dev/null +++ b/benchmarks/CHStone/gsm/lpc.c @@ -0,0 +1,323 @@ +/* ++--------------------------------------------------------------------------+ +| CHStone : a suite of benchmark programs for C-based High-Level Synthesis | +| ======================================================================== | +| | +| * Collected and Modified : Y. Hara, H. Tomiyama, S. Honda, | +| H. Takada and K. Ishii | +| Nagoya University, Japan | +| | +| * Remark : | +| 1. This source code is modified to unify the formats of the benchmark | +| programs in CHStone. | +| 2. Test vectors are added for CHStone. | +| 3. If "main_result" is 0 at the end of the program, the program is | +| correctly executed. | +| 4. Please follow the copyright of each benchmark program. | ++--------------------------------------------------------------------------+ +*/ +/* + * Copyright 1992 by Jutta Degener and Carsten Bormann, Technische + * Universitaet Berlin. See the accompanying file "COPYRIGHT" for + * details. THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE. + */ + +/* $Header: /home/kbs/jutta/src/gsm/gsm-1.0/src/RCS/lpc.c,v 1.5 1994/12/30 23:14:54 jutta Exp $ */ + +#include "private.h" +#include "add.c" + + +/* + * 4.2.4 .. 4.2.7 LPC ANALYSIS SECTION + */ + +/* 4.2.4 */ + + +void +Autocorrelation (word * s /* [0..159] IN/OUT */ , + longword * L_ACF /* [0..8] OUT */ ) +/* + * The goal is to compute the array L_ACF[k]. The signal s[i] must + * be scaled in order to avoid an overflow situation. + */ +{ + register int k, i; + + word temp; + word smax; + word scalauto, n; + word *sp; + word sl; + + /* Search for the maximum. + */ + smax = 0; + for (k = 0; k <= 159; k++) + { + temp = GSM_ABS (s[k]); + if (temp > smax) + smax = temp; + } + + /* Computation of the scaling factor. + */ + if (smax == 0) + scalauto = 0; + else + scalauto = 4 - gsm_norm ((longword) smax << 16); /* sub(4,..) */ + + if (scalauto > 0 && scalauto <= 4) + { + n = scalauto; + for (k = 0; k <= 159; k++) + s[k] = GSM_MULT_R (s[k], 16384 >> (n - 1)); + } + + /* Compute the L_ACF[..]. + */ + { + sp = s; + sl = *sp; + +#define STEP(k) L_ACF[k] += ((longword)sl * sp[ -(k) ]); + +#define NEXTI sl = *++sp + for (k = 8; k >= 0; k--) + L_ACF[k] = 0; + + STEP (0); + NEXTI; + STEP (0); + STEP (1); + NEXTI; + STEP (0); + STEP (1); + STEP (2); + NEXTI; + STEP (0); + STEP (1); + STEP (2); + STEP (3); + NEXTI; + STEP (0); + STEP (1); + STEP (2); + STEP (3); + STEP (4); + NEXTI; + STEP (0); + STEP (1); + STEP (2); + STEP (3); + STEP (4); + STEP (5); + NEXTI; + STEP (0); + STEP (1); + STEP (2); + STEP (3); + STEP (4); + STEP (5); + STEP (6); + NEXTI; + STEP (0); + STEP (1); + STEP (2); + STEP (3); + STEP (4); + STEP (5); + STEP (6); + STEP (7); + + for (i = 8; i <= 159; i++) + { + + NEXTI; + + STEP (0); + STEP (1); + STEP (2); + STEP (3); + STEP (4); + STEP (5); + STEP (6); + STEP (7); + STEP (8); + } + + for (k = 8; k >= 0; k--) + L_ACF[k] <<= 1; + + } + /* Rescaling of the array s[0..159] + */ + if (scalauto > 0) + for (k = 159; k >= 0; k--) + *s++ <<= scalauto; +} + +/* 4.2.5 */ + +void +Reflection_coefficients (longword * L_ACF /* 0...8 IN */ , + register word * r /* 0...7 OUT */ ) +{ + register int i, m, n; + register word temp; + word ACF[9]; /* 0..8 */ + word P[9]; /* 0..8 */ + word K[9]; /* 2..8 */ + + /* Schur recursion with 16 bits arithmetic. + */ + + if (L_ACF[0] == 0) + { + for (i = 8; i > 0; i--) + *r++ = 0; + return; + } + + temp = gsm_norm (L_ACF[0]); + for (i = 0; i <= 8; i++) + ACF[i] = SASR (L_ACF[i] << temp, 16); + + /* Initialize array P[..] and K[..] for the recursion. + */ + + for (i = 1; i <= 7; i++) + K[i] = ACF[i]; + for (i = 0; i <= 8; i++) + P[i] = ACF[i]; + + /* Compute reflection coefficients + */ + for (n = 1; n <= 8; n++, r++) + { + + temp = P[1]; + temp = GSM_ABS (temp); + if (P[0] < temp) + { + for (i = n; i <= 8; i++) + *r++ = 0; + return; + } + + *r = gsm_div (temp, P[0]); + + if (P[1] > 0) + *r = -*r; /* r[n] = sub(0, r[n]) */ + if (n == 8) + return; + + /* Schur recursion + */ + temp = GSM_MULT_R (P[1], *r); + P[0] = GSM_ADD (P[0], temp); + + for (m = 1; m <= 8 - n; m++) + { + temp = GSM_MULT_R (K[m], *r); + P[m] = GSM_ADD (P[m + 1], temp); + + temp = GSM_MULT_R (P[m + 1], *r); + K[m] = GSM_ADD (K[m], temp); + } + } +} + +/* 4.2.6 */ + +void +Transformation_to_Log_Area_Ratios (register word * r /* 0..7 IN/OUT */ ) +/* + * The following scaling for r[..] and LAR[..] has been used: + * + * r[..] = integer( real_r[..]*32768. ); -1 <= real_r < 1. + * LAR[..] = integer( real_LAR[..] * 16384 ); + * with -1.625 <= real_LAR <= 1.625 + */ +{ + register word temp; + register int i; + + + /* Computation of the LAR[0..7] from the r[0..7] + */ + for (i = 1; i <= 8; i++, r++) + { + + temp = *r; + temp = GSM_ABS (temp); + + if (temp < 22118) + { + temp >>= 1; + } + else if (temp < 31130) + { + temp -= 11059; + } + else + { + temp -= 26112; + temp <<= 2; + } + + *r = *r < 0 ? -temp : temp; + } +} + +/* 4.2.7 */ + +void +Quantization_and_coding (register word * LAR /* [0..7] IN/OUT */ ) +{ + register word temp; + + + /* This procedure needs four tables; the following equations + * give the optimum scaling for the constants: + * + * A[0..7] = integer( real_A[0..7] * 1024 ) + * B[0..7] = integer( real_B[0..7] * 512 ) + * MAC[0..7] = maximum of the LARc[0..7] + * MIC[0..7] = minimum of the LARc[0..7] + */ + +# undef STEP +# define STEP( A, B, MAC, MIC ) \ + temp = GSM_MULT( A, *LAR ); \ + temp = GSM_ADD( temp, B ); \ + temp = GSM_ADD( temp, 256 ); \ + temp = SASR( temp, 9 ); \ + *LAR = temp>MAC ? MAC - MIC : (temp<MIC ? 0 : temp - MIC); \ + LAR++; + + STEP (20480, 0, 31, -32); + STEP (20480, 0, 31, -32); + STEP (20480, 2048, 15, -16); + STEP (20480, -2560, 15, -16); + + STEP (13964, 94, 7, -8); + STEP (15360, -1792, 7, -8); + STEP (8534, -341, 3, -4); + STEP (9036, -1144, 3, -4); + +# undef STEP +} + +void +Gsm_LPC_Analysis (word * s /* 0..159 signals IN/OUT */ , + word * LARc /* 0..7 LARc's OUT */ ) +{ + longword L_ACF[9]; + + Autocorrelation (s, L_ACF); + Reflection_coefficients (L_ACF, LARc); + Transformation_to_Log_Area_Ratios (LARc); + Quantization_and_coding (LARc); +} |