Gonzalo Arcos
0f56254df3
SSE2 and improves the performance significantly. The decoder was taken from the gr-dvbt module from GNU Radio. - Disabled some logging functions in the ofdm_mac and ofdm_decode_signal blocks that were degrading the performance significantly. [Gonzalo Arcos | Rodrigo Ferreri]
1037 lines
30 KiB
C++
1037 lines
30 KiB
C++
/*
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* Copyright (C) 2013 Bastian Bloessl <bloessl@ccs-labs.org>
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include "utils.h"
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#include <cassert>
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#include <cstring>
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#include <math.h>
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// constellations for different modulations (normalized to avg power 1)
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const std::complex<double> BPSK_D[2] = {
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std::complex<double>(-1.0, 0.0), std::complex<double>(1.0, 0.0)};
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const std::complex<double> QPSK_D[4] = {
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std::complex<double>(-0.7071, -0.7071), std::complex<double>(-0.7071, 0.7071),
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std::complex<double>(+0.7071, -0.7071), std::complex<double>(+0.7071, 0.7071)};
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const std::complex<double> QAM16_D[16] = {
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std::complex<double>(-0.9487, -0.9487), std::complex<double>(-0.9487, -0.3162),
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std::complex<double>(-0.9487, 0.9487), std::complex<double>(-0.9487, 0.3162),
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std::complex<double>(-0.3162, -0.9487), std::complex<double>(-0.3162, -0.3162),
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std::complex<double>(-0.3162, 0.9487), std::complex<double>(-0.3162, 0.3162),
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std::complex<double>(0.9487, -0.9487), std::complex<double>(0.9487, -0.3162),
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std::complex<double>(0.9487, 0.9487), std::complex<double>(0.9487, 0.3162),
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std::complex<double>(0.3162, -0.9487), std::complex<double>(0.3162, -0.3162),
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std::complex<double>(0.3162, 0.9487), std::complex<double>(0.3162, 0.3162)};
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const std::complex<double> QAM64_D[64] = {
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std::complex<double>(-1.0801, -1.0801), std::complex<double>(-1.0801, -0.7715),
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std::complex<double>(-1.0801, -0.1543), std::complex<double>(-1.0801, -0.4629),
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std::complex<double>(-1.0801, 1.0801), std::complex<double>(-1.0801, 0.7715),
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std::complex<double>(-1.0801, 0.1543), std::complex<double>(-1.0801, 0.4629),
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std::complex<double>(-0.7715, -1.0801), std::complex<double>(-0.7715, -0.7715),
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std::complex<double>(-0.7715, -0.1543), std::complex<double>(-0.7715, -0.4629),
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std::complex<double>(-0.7715, 1.0801), std::complex<double>(-0.7715, 0.7715),
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std::complex<double>(-0.7715, 0.1543), std::complex<double>(-0.7715, 0.4629),
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std::complex<double>(-0.1543, -1.0801), std::complex<double>(-0.1543, -0.7715),
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std::complex<double>(-0.1543, -0.1543), std::complex<double>(-0.1543, -0.4629),
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std::complex<double>(-0.1543, 1.0801), std::complex<double>(-0.1543, 0.7715),
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std::complex<double>(-0.1543, 0.1543), std::complex<double>(-0.1543, 0.4629),
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std::complex<double>(-0.4629, -1.0801), std::complex<double>(-0.4629, -0.7715),
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std::complex<double>(-0.4629, -0.1543), std::complex<double>(-0.4629, -0.4629),
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std::complex<double>(-0.4629, 1.0801), std::complex<double>(-0.4629, 0.7715),
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std::complex<double>(-0.4629, 0.1543), std::complex<double>(-0.4629, 0.4629),
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std::complex<double>(1.0801, -1.0801), std::complex<double>(1.0801, -0.7715),
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std::complex<double>(1.0801, -0.1543), std::complex<double>(1.0801, -0.4629),
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std::complex<double>(1.0801, 1.0801), std::complex<double>(1.0801, 0.7715),
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std::complex<double>(1.0801, 0.1543), std::complex<double>(1.0801, 0.4629),
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std::complex<double>(0.7715, -1.0801), std::complex<double>(0.7715, -0.7715),
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std::complex<double>(0.7715, -0.1543), std::complex<double>(0.7715, -0.4629),
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std::complex<double>(0.7715, 1.0801), std::complex<double>(0.7715, 0.7715),
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std::complex<double>(0.7715, 0.1543), std::complex<double>(0.7715, 0.4629),
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std::complex<double>(0.1543, -1.0801), std::complex<double>(0.1543, -0.7715),
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std::complex<double>(0.1543, -0.1543), std::complex<double>(0.1543, -0.4629),
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std::complex<double>(0.1543, 1.0801), std::complex<double>(0.1543, 0.7715),
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std::complex<double>(0.1543, 0.1543), std::complex<double>(0.1543, 0.4629),
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std::complex<double>(0.4629, -1.0801), std::complex<double>(0.4629, -0.7715),
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std::complex<double>(0.4629, -0.1543), std::complex<double>(0.4629, -0.4629),
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std::complex<double>(0.4629, 1.0801), std::complex<double>(0.4629, 0.7715),
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std::complex<double>(0.4629, 0.1543), std::complex<double>(0.4629, 0.4629)};
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ofdm_param::ofdm_param(Encoding e) {
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encoding = e;
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switch(e) {
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case BPSK_1_2:
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n_bpsc = 1;
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n_cbps = 48;
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n_dbps = 24;
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rate_field = 0x0D; // 0b00001101
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break;
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case BPSK_3_4:
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n_bpsc = 1;
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n_cbps = 48;
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n_dbps = 36;
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rate_field = 0x0F; // 0b00001111
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break;
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case QPSK_1_2:
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n_bpsc = 2;
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n_cbps = 96;
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n_dbps = 48;
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rate_field = 0x05; // 0b00000101
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break;
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case QPSK_3_4:
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n_bpsc = 2;
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n_cbps = 96;
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n_dbps = 72;
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rate_field = 0x07; // 0b00000111
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break;
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case QAM16_1_2:
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n_bpsc = 4;
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n_cbps = 192;
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n_dbps = 96;
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rate_field = 0x09; // 0b00001001
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break;
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case QAM16_3_4:
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n_bpsc = 4;
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n_cbps = 192;
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n_dbps = 144;
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rate_field = 0x0B; // 0b00001011
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break;
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case QAM64_2_3:
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n_bpsc = 6;
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n_cbps = 288;
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n_dbps = 192;
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rate_field = 0x01; // 0b00000001
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break;
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case QAM64_3_4:
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n_bpsc = 6;
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n_cbps = 288;
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n_dbps = 216;
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rate_field = 0x03; // 0b00000011
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break;
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defaut:
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assert(false);
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break;
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}
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}
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void
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ofdm_param::print() {
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std::cout << "OFDM Parameters:" << std::endl;
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std::cout << "endcoding :" << encoding << std::endl;
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std::cout << "rate_field :" << (int)rate_field << std::endl;
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std::cout << "n_bpsc :" << n_bpsc << std::endl;
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std::cout << "n_cbps :" << n_cbps << std::endl;
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std::cout << "n_dbps :" << n_dbps << std::endl;
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}
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tx_param::tx_param(ofdm_param &ofdm, int psdu_length) {
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psdu_size = psdu_length;
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// number of symbols (17-11)
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n_sym = (int) ceil((16 + 8 * psdu_size + 6) / (double) ofdm.n_dbps);
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// number of bits of the data field (17-12)
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n_data = n_sym * ofdm.n_dbps;
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// number of padding bits (17-13)
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n_pad = n_data - (16 + 8 * psdu_size + 6);
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n_encoded_bits = n_sym * ofdm.n_cbps;
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}
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void
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tx_param::print() {
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std::cout << "TX Parameters:" << std::endl;
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std::cout << "psdu_size: " << psdu_size << std::endl;
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std::cout << "n_sym: " << n_sym << std::endl;
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std::cout << "n_data: " << n_data << std::endl;
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std::cout << "n_pad: " << n_pad << std::endl;
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}
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void scramble(const char *in, char *out, tx_param &tx, char initial_state) {
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int state = initial_state;
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int feedback;
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for (int i = 0; i < tx.n_data; i++) {
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feedback = (!!(state & 64)) ^ (!!(state & 8));
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out[i] = feedback ^ in[i];
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state = ((state << 1) & 0x7e) | feedback;
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}
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}
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void reset_tail_bits(char *scrambled_data, tx_param &tx) {
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memset(scrambled_data + tx.n_data - tx.n_pad - 6, 0, 6 * sizeof(char));
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}
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int ones(int n) {
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int sum = 0;
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for(int i = 0; i < 8; i++) {
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if(n & (1 << i)) {
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sum++;
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}
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}
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return sum;
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}
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void convolutional_encoding(const char *in, char *out, tx_param &tx) {
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int state = 0;
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for(int i = 0; i < tx.n_data; i++) {
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assert(in[i] == 0 || in[i] == 1);
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state = ((state << 1) & 0x7e) | in[i];
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out[i * 2] = ones(state & 0155) % 2;
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out[i * 2 + 1] = ones(state & 0117) % 2;
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}
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}
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void puncturing(const char *in, char *out, tx_param &tx, ofdm_param &ofdm) {
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int mod;
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for (int i = 0; i < tx.n_data * 2; i++) {
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switch(ofdm.encoding) {
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case BPSK_1_2:
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case QPSK_1_2:
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case QAM16_1_2:
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*out = in[i];
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out++;
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break;
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case QAM64_2_3:
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if (i % 4 != 3) {
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*out = in[i];
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out++;
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}
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break;
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case BPSK_3_4:
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case QPSK_3_4:
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case QAM16_3_4:
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case QAM64_3_4:
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mod = i % 6;
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if (!(mod == 3 || mod == 4)) {
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*out = in[i];
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out++;
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}
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break;
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defaut:
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assert(false);
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break;
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}
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}
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}
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void interleave(const char *in, char *out, tx_param &tx, ofdm_param &ofdm, bool reverse) {
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int n_cbps = ofdm.n_cbps;
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int first[n_cbps];
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int second[n_cbps];
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int s = std::max(ofdm.n_bpsc / 2, 1);
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for(int j = 0; j < n_cbps; j++) {
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first[j] = s * (j / s) + ((j + int(floor(16.0 * j / n_cbps))) % s);
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}
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for(int i = 0; i < n_cbps; i++) {
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second[i] = 16 * i - (n_cbps - 1) * int(floor(16.0 * i / n_cbps));
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}
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for(int i = 0; i < tx.n_sym; i++) {
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for(int k = 0; k < n_cbps; k++) {
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if(reverse) {
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out[i * n_cbps + second[first[k]]] = in[i * n_cbps + k];
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} else {
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out[i * n_cbps + k] = in[i * n_cbps + second[first[k]]];
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}
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}
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}
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}
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void interleave(const double *in, double *out, tx_param &tx, ofdm_param &ofdm, bool reverse) {
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int n_cbps = ofdm.n_cbps;
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int first[n_cbps];
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int second[n_cbps];
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int s = std::max(ofdm.n_bpsc / 2, 1);
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for(int j = 0; j < n_cbps; j++) {
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first[j] = s * (j / s) + ((j + int(floor(16.0 * j / n_cbps))) % s);
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}
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for(int i = 0; i < n_cbps; i++) {
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second[i] = 16 * i - (n_cbps - 1) * int(floor(16.0 * i / n_cbps));
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}
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for(int i = 0; i < tx.n_sym; i++) {
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for(int k = 0; k < n_cbps; k++) {
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if(reverse) {
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out[i * n_cbps + second[first[k]]] = in[i * n_cbps + k];
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} else {
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out[i * n_cbps + k] = in[i * n_cbps + second[first[k]]];
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}
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}
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}
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}
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void split_symbols(const char *in, char *out, tx_param &tx, ofdm_param &ofdm) {
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int symbols = tx.n_sym * 48;
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for (int i = 0; i < symbols; i++) {
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out[i] = 0;
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for(int k = 0; k < ofdm.n_bpsc; k++) {
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assert(*in == 1 || *in == 0);
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out[i] |= (*in << (ofdm.n_bpsc - k - 1));
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in++;
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}
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}
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}
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void generate_bits(const char *psdu, char *data_bits, tx_param &tx) {
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// first 16 bits are zero (SERVICE/DATA field)
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memset(data_bits, 0, 16);
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data_bits += 16;
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for(int i = 0; i < tx.psdu_size; i++) {
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for(int b = 0; b < 8; b++) {
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data_bits[i * 8 + b] = !!(psdu[i] & (1 << b));
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}
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}
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}
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/* Here starts the SSE2 Viterbi convolutional decoder implementation */
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/*
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* Copyright 1995 Phil Karn, KA9Q
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* Copyright 2008 Free Software Foundation, Inc.
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* 2014 Added SSE2 implementation Bogdan Diaconescu
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*
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* This file is part of GNU Radio
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*
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* GNU Radio is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 3, or (at your option)
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* any later version.
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*
|
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* GNU Radio is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
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* You should have received a copy of the GNU General Public License
|
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* along with GNU Radio; see the file COPYING. If not, write to
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* the Free Software Foundation, Inc., 51 Franklin Street,
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* Boston, MA 02110-1301, USA.
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*/
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/*
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* Viterbi decoder for K=7 rate=1/2 convolutional code
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* Some modifications from original Karn code by Matt Ettus
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* Major modifications by adding SSE2 code by Bogdan Diaconescu
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*/
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#include <xmmintrin.h>
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/* The two generator polynomials for the NASA Standard K=7 code.
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* Since these polynomials are known to be optimal for this constraint
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* length there is not much point in changing them. But if you do, you
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* will have to regenerate the BUTTERFLY macro calls in viterbi()
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*/
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#define POLYA 0x6d
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#define POLYB 0x4f
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/* The basic Viterbi decoder operation, called a "butterfly"
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* operation because of the way it looks on a trellis diagram. Each
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* butterfly involves an Add-Compare-Select (ACS) operation on the two nodes
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* where the 0 and 1 paths from the current node merge at the next step of
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* the trellis.
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*
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* The code polynomials are assumed to have 1's on both ends. Given a
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* function encode_state() that returns the two symbols for a given
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* encoder state in the low two bits, such a code will have the following
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* identities for even 'n' < 64:
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*
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* encode_state(n) = encode_state(n+65)
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* encode_state(n+1) = encode_state(n+64) = (3 ^ encode_state(n))
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*
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* Any convolutional code you would actually want to use will have
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* these properties, so these assumptions aren't too limiting.
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*
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* Doing this as a macro lets the compiler evaluate at compile time the
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* many expressions that depend on the loop index and encoder state and
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* emit them as immediate arguments.
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* This makes an enormous difference on register-starved machines such
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* as the Intel x86 family where evaluating these expressions at runtime
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* would spill over into memory.
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*/
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static union branchtab27 { unsigned char c[32]; __m128i v[2];} Branchtab27_sse2[2];
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// Maximum number of traceback bytes
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#define TRACEBACK_MAX 24
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// Metrics for each state
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static unsigned char mmresult[64] __attribute__((aligned(16))) = {0};
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// Paths for each state
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static unsigned char ppresult[TRACEBACK_MAX][64] __attribute__((aligned(16))) = {{0,0}};
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// Position in circular buffer where the current decoded byte is stored
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static int store_pos = 0;
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#define BUTTERFLY(i,sym) { \
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int m0,m1,m2,m3;\
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/* ACS for 0 branch */\
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m0 = state[i].metric + mets[sym]; /* 2*i */\
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m1 = state[i+32].metric + mets[3 ^ sym]; /* 2*i + 64 */\
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if(m0 > m1){\
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next[2*i].metric = m0;\
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next[2*i].path = state[i].path << 1;\
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} else {\
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next[2*i].metric = m1;\
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next[2*i].path = (state[i+32].path << 1)|1;\
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}\
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/* ACS for 1 branch */\
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m2 = state[i].metric + mets[3 ^ sym]; /* 2*i + 1 */\
|
|
m3 = state[i+32].metric + mets[sym]; /* 2*i + 65 */\
|
|
if(m2 > m3){\
|
|
next[2*i+1].metric = m2;\
|
|
next[2*i+1].path = state[i].path << 1;\
|
|
} else {\
|
|
next[2*i+1].metric = m3;\
|
|
next[2*i+1].path = (state[i+32].path << 1)|1;\
|
|
}\
|
|
}
|
|
|
|
unsigned char d_Partab[] = {
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
0, 1, 1, 0, 1, 0, 0, 1,
|
|
1, 0, 0, 1, 0, 1, 1, 0,
|
|
};/* Parity lookup table */
|
|
|
|
/* Convolutionally encode data into binary symbols */
|
|
unsigned char
|
|
d_encode(unsigned char *symbols,
|
|
unsigned char *data,
|
|
unsigned int nbytes,
|
|
unsigned char encstate)
|
|
{
|
|
int i;
|
|
|
|
while(nbytes-- != 0){
|
|
for(i=7;i>=0;i--){
|
|
encstate = (encstate << 1) | ((*data >> i) & 1);
|
|
*symbols++ = d_Partab[encstate & POLYA];
|
|
*symbols++ = d_Partab[encstate & POLYB];
|
|
}
|
|
data++;
|
|
}
|
|
|
|
return encstate;
|
|
}
|
|
|
|
/* Viterbi decoder */
|
|
int
|
|
d_viterbi(unsigned long *metric, /* Final path metric (returned value) */
|
|
unsigned char *data, /* Decoded output data */
|
|
unsigned char *symbols, /* Raw deinterleaved input symbols */
|
|
unsigned int nbits, /* Number of output bits */
|
|
int mettab[2][256] /* Metric table, [sent sym][rx symbol] */
|
|
){
|
|
unsigned int bitcnt = 0;
|
|
int mets[4];
|
|
long bestmetric;
|
|
int beststate,i;
|
|
struct viterbi_state state0[64],state1[64],*state,*next;
|
|
|
|
state = state0;
|
|
next = state1;
|
|
|
|
/* Initialize starting metrics to prefer 0 state */
|
|
state[0].metric = 0;
|
|
for(i=1;i<64;i++)
|
|
state[i].metric = -999999;
|
|
state[0].path = 0;
|
|
|
|
for(bitcnt = 0;bitcnt < nbits;bitcnt++){
|
|
/* Read input symbol pair and compute all possible branch
|
|
* metrics
|
|
*/
|
|
mets[0] = mettab[0][symbols[0]] + mettab[0][symbols[1]];
|
|
mets[1] = mettab[0][symbols[0]] + mettab[1][symbols[1]];
|
|
mets[2] = mettab[1][symbols[0]] + mettab[0][symbols[1]];
|
|
mets[3] = mettab[1][symbols[0]] + mettab[1][symbols[1]];
|
|
symbols += 2;
|
|
|
|
BUTTERFLY(0,0); BUTTERFLY(1,1); BUTTERFLY(2,3); BUTTERFLY(3,2);
|
|
BUTTERFLY(4,3); BUTTERFLY(5,2); BUTTERFLY(6,0); BUTTERFLY(7,1);
|
|
BUTTERFLY(8,0); BUTTERFLY(9,1); BUTTERFLY(10,3); BUTTERFLY(11,2);
|
|
BUTTERFLY(12,3); BUTTERFLY(13,2); BUTTERFLY(14,0); BUTTERFLY(15,1);
|
|
BUTTERFLY(16,2); BUTTERFLY(17,3); BUTTERFLY(18,1); BUTTERFLY(19,0);
|
|
BUTTERFLY(20,1); BUTTERFLY(21,0); BUTTERFLY(22,2); BUTTERFLY(23,3);
|
|
BUTTERFLY(24,2); BUTTERFLY(25,3); BUTTERFLY(26,1); BUTTERFLY(27,0);
|
|
BUTTERFLY(28,1); BUTTERFLY(29,0); BUTTERFLY(30,2); BUTTERFLY(31,3);
|
|
|
|
/* Swap current and next states */
|
|
if(bitcnt & 1){
|
|
state = state0;
|
|
next = state1;
|
|
} else {
|
|
state = state1;
|
|
next = state0;
|
|
}
|
|
// ETTUS
|
|
//if(bitcnt > nbits-7){
|
|
/* In tail, poison non-zero nodes */
|
|
//for(i=1;i<64;i += 2)
|
|
// state[i].metric = -9999999;
|
|
//}
|
|
/* Produce output every 8 bits once path memory is full */
|
|
if((bitcnt % 8) == 5 && bitcnt > 32){
|
|
/* Find current best path */
|
|
bestmetric = state[0].metric;
|
|
beststate = 0;
|
|
for(i=1;i<64;i++){
|
|
if(state[i].metric > bestmetric){
|
|
bestmetric = state[i].metric;
|
|
beststate = i;
|
|
}
|
|
}
|
|
#ifdef notdef
|
|
printf("metrics[%d] = %d state = %lx\n",beststate,
|
|
state[beststate].metric,state[beststate].path);
|
|
#endif
|
|
*data++ = state[beststate].path >> 24;
|
|
}
|
|
|
|
}
|
|
/* Output remaining bits from 0 state */
|
|
// ETTUS Find best state instead
|
|
bestmetric = state[0].metric;
|
|
beststate = 0;
|
|
for(i=1;i<64;i++){
|
|
if(state[i].metric > bestmetric){
|
|
bestmetric = state[i].metric;
|
|
beststate = i;
|
|
}
|
|
}
|
|
if((i = bitcnt % 8) != 6)
|
|
state[beststate].path <<= 6-i;
|
|
|
|
*data++ = state[beststate].path >> 24;
|
|
*data++ = state[beststate].path >> 16;
|
|
*data++ = state[beststate].path >> 8;
|
|
*data = state[beststate].path;
|
|
//printf ("BS = %d\tBSM = %d\tM0 = %d\n",beststate,state[beststate].metric,state[0].metric);
|
|
*metric = state[beststate].metric;
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
d_viterbi_chunks_init(struct viterbi_state* state) {
|
|
// Initialize starting metrics to prefer 0 state
|
|
int i;
|
|
state[0].metric = 0;
|
|
state[0].path = 0;
|
|
for(i=1;i<64;i++)
|
|
{
|
|
state[i].metric = 0;//-999999;
|
|
state[i].path = 0;
|
|
}
|
|
}
|
|
|
|
void
|
|
d_viterbi_chunks_init_sse2(__m128i *mm0, __m128i *pp0) {
|
|
// Initialize starting metrics to prefer 0 state
|
|
int i, j;
|
|
|
|
for (i = 0; i < 4; i++)
|
|
{
|
|
mm0[i] = _mm_setzero_si128();
|
|
pp0[i] = _mm_setzero_si128();
|
|
}
|
|
|
|
int polys[2] = { POLYA, POLYB };
|
|
for(i=0; i < 32; i++)
|
|
{
|
|
Branchtab27_sse2[0].c[i] = (polys[0] < 0) ^ d_Partab[(2*i) & abs(polys[0])] ? 1 : 0;
|
|
Branchtab27_sse2[1].c[i] = (polys[1] < 0) ^ d_Partab[(2*i) & abs(polys[1])] ? 1 : 0;
|
|
}
|
|
|
|
for (i = 0; i < 64; i++)
|
|
{
|
|
mmresult[i] = 0;
|
|
for (j = 0; j < TRACEBACK_MAX; j++)
|
|
ppresult[j][i] = 0;
|
|
}
|
|
}
|
|
|
|
|
|
void
|
|
d_viterbi_butterfly8(unsigned char *symbols, int mettab[2][256], struct viterbi_state *state0, struct viterbi_state *state1)
|
|
{
|
|
unsigned int bitcnt;
|
|
int mets[4];
|
|
|
|
struct viterbi_state *state, *next;
|
|
state = state0;
|
|
next = state1;
|
|
// Operate on 16 symbols (8 bits) at a time
|
|
for(bitcnt = 0;bitcnt < 8;bitcnt++){
|
|
// Read input symbol pair and compute all possible branch metrics
|
|
mets[0] = mettab[0][symbols[0]] + mettab[0][symbols[1]];
|
|
mets[1] = mettab[0][symbols[0]] + mettab[1][symbols[1]];
|
|
mets[2] = mettab[1][symbols[0]] + mettab[0][symbols[1]];
|
|
mets[3] = mettab[1][symbols[0]] + mettab[1][symbols[1]];
|
|
symbols += 2;
|
|
|
|
// These macro calls were generated by genbut.c
|
|
BUTTERFLY(0,0); BUTTERFLY(1,1); BUTTERFLY(2,3); BUTTERFLY(3,2);
|
|
BUTTERFLY(4,3); BUTTERFLY(5,2); BUTTERFLY(6,0); BUTTERFLY(7,1);
|
|
BUTTERFLY(8,0); BUTTERFLY(9,1); BUTTERFLY(10,3); BUTTERFLY(11,2);
|
|
BUTTERFLY(12,3); BUTTERFLY(13,2); BUTTERFLY(14,0); BUTTERFLY(15,1);
|
|
BUTTERFLY(16,2); BUTTERFLY(17,3); BUTTERFLY(18,1); BUTTERFLY(19,0);
|
|
BUTTERFLY(20,1); BUTTERFLY(21,0); BUTTERFLY(22,2); BUTTERFLY(23,3);
|
|
BUTTERFLY(24,2); BUTTERFLY(25,3); BUTTERFLY(26,1); BUTTERFLY(27,0);
|
|
BUTTERFLY(28,1); BUTTERFLY(29,0); BUTTERFLY(30,2); BUTTERFLY(31,3);
|
|
|
|
// Swap current and next states
|
|
if(bitcnt & 1){
|
|
state = state0;
|
|
next = state1;
|
|
} else {
|
|
state = state1;
|
|
next = state0;
|
|
}
|
|
}
|
|
}
|
|
|
|
void
|
|
d_viterbi_butterfly2(unsigned char *symbols, int mettab[2][256], struct viterbi_state *state0, struct viterbi_state *state1)
|
|
{
|
|
int mets[4];
|
|
|
|
struct viterbi_state *state, *next;
|
|
state = state0;
|
|
next = state1;
|
|
|
|
// Operate on 4 symbols (2 bits) at a time
|
|
|
|
// Read input symbol pair and compute all possible branch metrics
|
|
#if 0
|
|
if (symbols[0] == 2)
|
|
{
|
|
mets[0] = mettab[0][symbols[1]];
|
|
mets[1] = mettab[1][symbols[1]];
|
|
mets[2] = mettab[0][symbols[1]];
|
|
mets[3] = mettab[1][symbols[1]];
|
|
}
|
|
else if (symbols[1] == 2)
|
|
{
|
|
mets[0] = mettab[0][symbols[0]];
|
|
mets[1] = mettab[1][symbols[0]];
|
|
mets[2] = mettab[0][symbols[0]];
|
|
mets[3] = mettab[1][symbols[0]];
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
mets[0] = mettab[0][symbols[0]] + mettab[0][symbols[1]];
|
|
mets[1] = mettab[0][symbols[0]] + mettab[1][symbols[1]];
|
|
mets[2] = mettab[1][symbols[0]] + mettab[0][symbols[1]];
|
|
mets[3] = mettab[1][symbols[0]] + mettab[1][symbols[1]];
|
|
}
|
|
|
|
// These macro calls were generated by genbut.c
|
|
BUTTERFLY(0,0); BUTTERFLY(1,1); BUTTERFLY(2,3); BUTTERFLY(3,2);
|
|
BUTTERFLY(4,3); BUTTERFLY(5,2); BUTTERFLY(6,0); BUTTERFLY(7,1);
|
|
BUTTERFLY(8,0); BUTTERFLY(9,1); BUTTERFLY(10,3); BUTTERFLY(11,2);
|
|
BUTTERFLY(12,3); BUTTERFLY(13,2); BUTTERFLY(14,0); BUTTERFLY(15,1);
|
|
BUTTERFLY(16,2); BUTTERFLY(17,3); BUTTERFLY(18,1); BUTTERFLY(19,0);
|
|
BUTTERFLY(20,1); BUTTERFLY(21,0); BUTTERFLY(22,2); BUTTERFLY(23,3);
|
|
BUTTERFLY(24,2); BUTTERFLY(25,3); BUTTERFLY(26,1); BUTTERFLY(27,0);
|
|
BUTTERFLY(28,1); BUTTERFLY(29,0); BUTTERFLY(30,2); BUTTERFLY(31,3);
|
|
|
|
state = state1;
|
|
next = state0;
|
|
|
|
// Read input symbol pair and compute all possible branch metrics
|
|
|
|
#if 0
|
|
if (symbols[2] == 2)
|
|
{
|
|
mets[0] = mettab[0][symbols[3]];
|
|
mets[1] = mettab[1][symbols[3]];
|
|
mets[2] = mettab[0][symbols[3]];
|
|
mets[3] = mettab[1][symbols[3]];
|
|
}
|
|
else if (symbols[3] == 2)
|
|
{
|
|
mets[0] = mettab[0][symbols[2]];
|
|
mets[1] = mettab[1][symbols[2]];
|
|
mets[2] = mettab[0][symbols[2]];
|
|
mets[3] = mettab[1][symbols[2]];
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
mets[0] = mettab[0][symbols[2]] + mettab[0][symbols[3]];
|
|
mets[1] = mettab[0][symbols[2]] + mettab[1][symbols[3]];
|
|
mets[2] = mettab[1][symbols[2]] + mettab[0][symbols[3]];
|
|
mets[3] = mettab[1][symbols[2]] + mettab[1][symbols[3]];
|
|
}
|
|
|
|
// These macro calls were generated by genbut.c
|
|
BUTTERFLY(0,0); BUTTERFLY(1,1); BUTTERFLY(2,3); BUTTERFLY(3,2);
|
|
BUTTERFLY(4,3); BUTTERFLY(5,2); BUTTERFLY(6,0); BUTTERFLY(7,1);
|
|
BUTTERFLY(8,0); BUTTERFLY(9,1); BUTTERFLY(10,3); BUTTERFLY(11,2);
|
|
BUTTERFLY(12,3); BUTTERFLY(13,2); BUTTERFLY(14,0); BUTTERFLY(15,1);
|
|
BUTTERFLY(16,2); BUTTERFLY(17,3); BUTTERFLY(18,1); BUTTERFLY(19,0);
|
|
BUTTERFLY(20,1); BUTTERFLY(21,0); BUTTERFLY(22,2); BUTTERFLY(23,3);
|
|
BUTTERFLY(24,2); BUTTERFLY(25,3); BUTTERFLY(26,1); BUTTERFLY(27,0);
|
|
BUTTERFLY(28,1); BUTTERFLY(29,0); BUTTERFLY(30,2); BUTTERFLY(31,3);
|
|
}
|
|
|
|
void
|
|
d_viterbi_butterfly2_sse2(unsigned char *symbols, __m128i *mm0, __m128i *mm1, __m128i *pp0, __m128i *pp1)
|
|
{
|
|
int i;
|
|
|
|
__m128i *metric0, *metric1;
|
|
__m128i *path0, *path1;
|
|
|
|
metric0 = mm0;
|
|
path0 = pp0;
|
|
metric1 = mm1;
|
|
path1 = pp1;
|
|
|
|
// Operate on 4 symbols (2 bits) at a time
|
|
|
|
__m128i m0, m1, m2, m3, decision0, decision1, survivor0, survivor1;
|
|
__m128i metsv, metsvm;
|
|
__m128i shift0, shift1;
|
|
__m128i tmp0, tmp1;
|
|
__m128i sym0v, sym1v;
|
|
|
|
sym0v = _mm_set1_epi8(symbols[0]);
|
|
sym1v = _mm_set1_epi8(symbols[1]);
|
|
|
|
for (i = 0; i < 2; i++)
|
|
{
|
|
if (symbols[0] == 2)
|
|
{
|
|
metsvm = _mm_xor_si128(Branchtab27_sse2[1].v[i],sym1v);
|
|
metsv = _mm_sub_epi8(_mm_set1_epi8(1),metsvm);
|
|
}
|
|
else if (symbols[1] == 2)
|
|
{
|
|
metsvm = _mm_xor_si128(Branchtab27_sse2[0].v[i],sym0v);
|
|
metsv = _mm_sub_epi8(_mm_set1_epi8(1),metsvm);
|
|
}
|
|
else
|
|
{
|
|
metsvm = _mm_add_epi8(_mm_xor_si128(Branchtab27_sse2[0].v[i],sym0v),_mm_xor_si128(Branchtab27_sse2[1].v[i],sym1v));
|
|
metsv = _mm_sub_epi8(_mm_set1_epi8(2),metsvm);
|
|
}
|
|
|
|
m0 = _mm_add_epi8(metric0[i], metsv);
|
|
m1 = _mm_add_epi8(metric0[i+2], metsvm);
|
|
m2 = _mm_add_epi8(metric0[i], metsvm);
|
|
m3 = _mm_add_epi8(metric0[i+2], metsv);
|
|
|
|
decision0 = _mm_cmpgt_epi8(_mm_sub_epi8(m0,m1),_mm_setzero_si128());
|
|
decision1 = _mm_cmpgt_epi8(_mm_sub_epi8(m2,m3),_mm_setzero_si128());
|
|
survivor0 = _mm_or_si128(_mm_and_si128(decision0,m0),_mm_andnot_si128(decision0,m1));
|
|
survivor1 = _mm_or_si128(_mm_and_si128(decision1,m2),_mm_andnot_si128(decision1,m3));
|
|
|
|
shift0 = _mm_slli_epi16(path0[i], 1);
|
|
shift1 = _mm_slli_epi16(path0[2+i], 1);
|
|
shift1 = _mm_add_epi8(shift1, _mm_set1_epi8(1));
|
|
|
|
metric1[2*i] = _mm_unpacklo_epi8(survivor0,survivor1);
|
|
tmp0 = _mm_or_si128(_mm_and_si128(decision0,shift0),_mm_andnot_si128(decision0,shift1));
|
|
|
|
metric1[2*i+1] = _mm_unpackhi_epi8(survivor0,survivor1);
|
|
tmp1 = _mm_or_si128(_mm_and_si128(decision1,shift0),_mm_andnot_si128(decision1,shift1));
|
|
|
|
path1[2*i] = _mm_unpacklo_epi8(tmp0, tmp1);
|
|
path1[2*i+1] = _mm_unpackhi_epi8(tmp0, tmp1);
|
|
}
|
|
|
|
metric0 = mm1;
|
|
path0 = pp1;
|
|
metric1 = mm0;
|
|
path1 = pp0;
|
|
|
|
sym0v = _mm_set1_epi8(symbols[2]);
|
|
sym1v = _mm_set1_epi8(symbols[3]);
|
|
|
|
for (i = 0; i < 2; i++)
|
|
{
|
|
if (symbols[2] == 2)
|
|
{
|
|
metsvm = _mm_xor_si128(Branchtab27_sse2[1].v[i],sym1v);
|
|
metsv = _mm_sub_epi8(_mm_set1_epi8(1),metsvm);
|
|
}
|
|
else if (symbols[3] == 2)
|
|
{
|
|
metsvm = _mm_xor_si128(Branchtab27_sse2[0].v[i],sym0v);
|
|
metsv = _mm_sub_epi8(_mm_set1_epi8(1),metsvm);
|
|
}
|
|
else
|
|
{
|
|
metsvm = _mm_add_epi8(_mm_xor_si128(Branchtab27_sse2[0].v[i],sym0v),_mm_xor_si128(Branchtab27_sse2[1].v[i],sym1v));
|
|
metsv = _mm_sub_epi8(_mm_set1_epi8(2),metsvm);
|
|
}
|
|
|
|
m0 = _mm_add_epi8(metric0[i], metsv);
|
|
m1 = _mm_add_epi8(metric0[i+2], metsvm);
|
|
m2 = _mm_add_epi8(metric0[i], metsvm);
|
|
m3 = _mm_add_epi8(metric0[i+2], metsv);
|
|
|
|
decision0 = _mm_cmpgt_epi8(_mm_sub_epi8(m0,m1),_mm_setzero_si128());
|
|
decision1 = _mm_cmpgt_epi8(_mm_sub_epi8(m2,m3),_mm_setzero_si128());
|
|
survivor0 = _mm_or_si128(_mm_and_si128(decision0,m0),_mm_andnot_si128(decision0,m1));
|
|
survivor1 = _mm_or_si128(_mm_and_si128(decision1,m2),_mm_andnot_si128(decision1,m3));
|
|
|
|
shift0 = _mm_slli_epi16(path0[i], 1);
|
|
shift1 = _mm_slli_epi16(path0[2+i], 1);
|
|
shift1 = _mm_add_epi8(shift1, _mm_set1_epi8(1));
|
|
|
|
metric1[2*i] = _mm_unpacklo_epi8(survivor0,survivor1);
|
|
tmp0 = _mm_or_si128(_mm_and_si128(decision0,shift0),_mm_andnot_si128(decision0,shift1));
|
|
|
|
metric1[2*i+1] = _mm_unpackhi_epi8(survivor0,survivor1);
|
|
tmp1 = _mm_or_si128(_mm_and_si128(decision1,shift0),_mm_andnot_si128(decision1,shift1));
|
|
|
|
path1[2*i] = _mm_unpacklo_epi8(tmp0, tmp1);
|
|
path1[2*i+1] = _mm_unpackhi_epi8(tmp0, tmp1);
|
|
}
|
|
}
|
|
|
|
void
|
|
d_viterbi_butterfly_sse2(unsigned char *symbols, __m128i *mm0, __m128i *mm1, __m128i *pp0, __m128i *pp1)
|
|
{
|
|
int i;
|
|
|
|
__m128i *metric0, *metric1;
|
|
__m128i *path0, *path1;
|
|
|
|
metric0 = mm0;
|
|
path0 = pp0;
|
|
metric1 = mm1;
|
|
path1 = pp1;
|
|
|
|
for (i = 0; i < 2; i++)
|
|
printf("symbols[%i]: %i\n", i, symbols[i]);
|
|
|
|
|
|
// Operate on 4 symbols (2 bits) at a time
|
|
|
|
__m128i m0, m1, m2, m3, decision0, decision1, survivor0, survivor1;
|
|
__m128i metsv, metsvm;
|
|
__m128i shift0, shift1;
|
|
__m128i tmp0, tmp1;
|
|
__m128i sym0v, sym1v;
|
|
|
|
sym0v = _mm_set1_epi8(symbols[0]);
|
|
sym1v = _mm_set1_epi8(symbols[1]);
|
|
|
|
for (i = 0; i < 2; i++)
|
|
{
|
|
#if 1
|
|
if (symbols[0] == 2)
|
|
{
|
|
metsvm = _mm_xor_si128(Branchtab27_sse2[1].v[i],sym1v);
|
|
}
|
|
else if (symbols[1] == 0)
|
|
{
|
|
metsvm = _mm_xor_si128(Branchtab27_sse2[0].v[i],sym0v);
|
|
}
|
|
else
|
|
#endif
|
|
metsvm = _mm_add_epi8(_mm_xor_si128(Branchtab27_sse2[0].v[i],sym0v),_mm_xor_si128(Branchtab27_sse2[1].v[i],sym1v));
|
|
|
|
metsv = _mm_sub_epi8(_mm_set1_epi8(2),metsvm);
|
|
|
|
m0 = _mm_add_epi8(metric0[i], metsv);
|
|
m1 = _mm_add_epi8(metric0[i+2], metsvm);
|
|
m2 = _mm_add_epi8(metric0[i], metsvm);
|
|
m3 = _mm_add_epi8(metric0[i+2], metsv);
|
|
|
|
decision0 = _mm_cmpgt_epi8(_mm_sub_epi8(m0,m1),_mm_setzero_si128());
|
|
decision1 = _mm_cmpgt_epi8(_mm_sub_epi8(m2,m3),_mm_setzero_si128());
|
|
survivor0 = _mm_or_si128(_mm_and_si128(decision0,m0),_mm_andnot_si128(decision0,m1));
|
|
survivor1 = _mm_or_si128(_mm_and_si128(decision1,m2),_mm_andnot_si128(decision1,m3));
|
|
|
|
shift0 = _mm_slli_epi16(path0[i], 1);
|
|
shift1 = _mm_slli_epi16(path0[2+i], 1);
|
|
shift1 = _mm_add_epi8(shift1, _mm_set1_epi8(1));
|
|
|
|
metric1[2*i] = _mm_unpacklo_epi8(survivor0,survivor1);
|
|
tmp0 = _mm_or_si128(_mm_and_si128(decision0,shift0),_mm_andnot_si128(decision0,shift1));
|
|
|
|
metric1[2*i+1] = _mm_unpackhi_epi8(survivor0,survivor1);
|
|
tmp1 = _mm_or_si128(_mm_and_si128(decision1,shift0),_mm_andnot_si128(decision1,shift1));
|
|
|
|
path1[2*i] = _mm_unpacklo_epi8(tmp0, tmp1);
|
|
path1[2*i+1] = _mm_unpackhi_epi8(tmp0, tmp1);
|
|
}
|
|
|
|
for (i = 0; i < 4; i++)
|
|
{
|
|
mm0[i] = metric1[i];
|
|
pp0[i] = path1[i];
|
|
}
|
|
|
|
}
|
|
|
|
|
|
unsigned char
|
|
d_viterbi_get_output(struct viterbi_state *state, unsigned char *outbuf) {
|
|
// Produce output every 8 bits once path memory is full
|
|
// if((bitcnt % 8) == 5 && bitcnt > 32) {
|
|
|
|
// Find current best path
|
|
unsigned int i, beststate = 0;
|
|
int bestmetric;
|
|
|
|
bestmetric = state[0].metric;
|
|
beststate = 0;
|
|
for(i=1;i<64;i++)
|
|
{
|
|
if(state[i].metric > bestmetric) {
|
|
bestmetric = state[i].metric;
|
|
beststate = i;
|
|
}
|
|
}
|
|
|
|
*outbuf = state[beststate].path >> 24;
|
|
|
|
return bestmetric;
|
|
}
|
|
|
|
unsigned char
|
|
d_viterbi_get_output_sse2(__m128i *mm0, __m128i *pp0, int ntraceback, unsigned char *outbuf) {
|
|
// Find current best path
|
|
int i;
|
|
int bestmetric, minmetric;
|
|
int beststate = 0;
|
|
int pos = 0;
|
|
|
|
// Implement a circular buffer with the last ntraceback paths
|
|
store_pos = (store_pos + 1) % ntraceback;
|
|
|
|
// TODO - find another way to extract the value
|
|
for (i = 0; i < 4; i++)
|
|
{
|
|
_mm_store_si128((__m128i *) &mmresult[i*16], mm0[i]);
|
|
_mm_store_si128((__m128i *) &ppresult[store_pos][i*16], pp0[i]);
|
|
}
|
|
|
|
// Find out the best final state
|
|
bestmetric = mmresult[beststate];
|
|
minmetric = mmresult[beststate];
|
|
|
|
for (i = 1; i < 64; i++)
|
|
{
|
|
if (mmresult[i] > bestmetric)
|
|
{
|
|
bestmetric = mmresult[i];
|
|
beststate = i;
|
|
}
|
|
if (mmresult[i] < minmetric)
|
|
minmetric = mmresult[i];
|
|
}
|
|
|
|
// Trace back
|
|
for (i = 0, pos = store_pos; i < (ntraceback - 1); i++)
|
|
{
|
|
// Obtain the state from the output bits
|
|
// by clocking in the output bits in reverse order.
|
|
// The state has only 6 bits
|
|
beststate = ppresult[pos][beststate] >> 2;
|
|
pos = (pos - 1 + ntraceback) % ntraceback;
|
|
}
|
|
|
|
// Store output byte
|
|
*outbuf = ppresult[pos][beststate];
|
|
|
|
// Zero out the path variable
|
|
// and prevent metric overflow
|
|
for (i = 0; i < 4; i++)
|
|
{
|
|
pp0[i] = _mm_setzero_si128();
|
|
mm0[i] = _mm_sub_epi8(mm0[i], _mm_set1_epi8(minmetric));
|
|
}
|
|
|
|
return bestmetric;
|
|
}
|
|
/* end of new functions */
|