viterbi decoder: add viterbi decoder base class

Add a viterbi decoder base class that viterbi decoder
implementations can inherit from.

lib/CMakeLists.txt

@@ -120,6 +120,7 @@ list(APPEND gr_ieee802_11_sources
     sync_long.cc
     sync_short.cc
     utils.cc
+    viterbi_decoder/base.cc
 )
 
 # use SSE2 optimized viterbi implementation if SSE2 is enabled

lib/viterbi_decoder/base.cc

@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2016 Bastian Bloessl <bloessl@ccs-labs.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "base.h"
+#include <cstring>
+#include <iostream>
+
+using namespace gr::ieee802_11;
+
+base::base() :
+	d_store_pos(0) {
+}
+
+base::~base() {
+}
+
+uint8_t*
+base::depuncture(uint8_t *in) {
+
+	int count;
+	int n_cbps = d_ofdm->n_cbps;
+	uint8_t *depunctured;
+
+	if (d_ntraceback == 5) {
+		count = d_frame->n_sym * n_cbps;
+		depunctured = in;
+
+	} else {
+		depunctured = d_depunctured;
+		count = 0;
+		for(int i = 0; i < d_frame->n_sym; i++) {
+			for(int k = 0; k < n_cbps; k++) {
+				while (d_depuncture_pattern[count % (2 * d_k)] == 0) {
+					depunctured[count] = 2;
+					count++;
+				}
+
+				// Insert received bits
+				depunctured[count] = in[i * n_cbps + k];
+				count++;
+
+				while (d_depuncture_pattern[count % (2 * d_k)] == 0) {
+					depunctured[count] = 2;
+					count++;
+				}
+			}
+		}
+	}
+
+	return depunctured;
+}
+
+/* Parity lookup table */
+const unsigned char base::PARTAB[256] = {
+	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,
+};
+
+const unsigned char base::PUNCTURE_1_2[2] = {1, 1};
+const unsigned char base::PUNCTURE_2_3[4] = {1, 1, 1, 0};
+const unsigned char base::PUNCTURE_3_4[6] = {1, 1, 1, 0, 0, 1};

lib/viterbi_decoder/base.h

@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2016 Bastian Bloessl <bloessl@ccs-labs.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef INCLUDED_IEEE802_11_VITERBI_DECODER_BASE_H
+#define INCLUDED_IEEE802_11_VITERBI_DECODER_BASE_H
+
+#include "utils.h"
+
+namespace gr {
+namespace ieee802_11 {
+
+// Maximum number of traceback bytes
+#define TRACEBACK_MAX 24
+
+/* This Viterbi decoder was taken from the gr-dvbt module of
+ * GNU Radio. It is an SSE2 version of the Viterbi Decoder
+ * created by Phil Karn. The SSE2 version was made by Bogdan
+ * Diaconescu. For more info see: gr-dvbt/lib/d_viterbi.h
+ */
+class base
+{
+public:
+
+	base();
+	~base();
+	virtual uint8_t* decode(ofdm_param *ofdm, frame_param *frame, uint8_t *in) = 0;
+
+protected:
+	// Position in circular buffer where the current decoded byte is stored
+	int d_store_pos;
+	// Metrics for each state
+	unsigned char d_mmresult[64] __attribute__((aligned(16)));
+	// Paths for each state
+	unsigned char d_ppresult[TRACEBACK_MAX][64] __attribute__((aligned(16)));
+
+	int d_ntraceback;
+	int d_k;
+	ofdm_param *d_ofdm;
+	frame_param *d_frame;
+	const unsigned char *d_depuncture_pattern;
+
+	uint8_t d_depunctured[MAX_ENCODED_BITS];
+	uint8_t d_decoded[MAX_ENCODED_BITS * 3 / 4];
+
+	static const unsigned char PARTAB[256];
+	static const unsigned char PUNCTURE_1_2[2];
+	static const unsigned char PUNCTURE_2_3[4];
+	static const unsigned char PUNCTURE_3_4[6];
+
+	virtual void reset() = 0;
+	uint8_t* depuncture(uint8_t *in);
+};
+
+} // namespace ieee802_11
+} // namespace gr
+
+#endif /* INCLUDED_IEEE802_11_VITERBI_DECODER_BASE_H */

lib/viterbi_decoder/viterbi_decoder_generic.cc

@@ -27,7 +27,7 @@
  * Some modifications from original Karn code by Matt Ettus
  * Major modifications by adding SSE2 code by Bogdan Diaconescu
  */
-#include "viterbi_decoder.h"
+#include "viterbi_decoder_generic.h"
 #include <cstring>
 #include <iostream>
 
@@ -83,13 +83,6 @@
 using namespace gr::ieee802_11;
 
 
-viterbi_decoder::viterbi_decoder() :
-	d_store_pos(0) {
-}
-
-viterbi_decoder::~viterbi_decoder() {
-}
-
 void
 viterbi_decoder::viterbi_butterfly2_generic(unsigned char *symbols,
 		unsigned char *mm0, unsigned char *mm1, unsigned char *pp0,
@@ -292,9 +285,7 @@ viterbi_decoder::viterbi_get_output_generic(unsigned char *mm0,
 	int bestmetric, minmetric;
 	int beststate = 0;
 	int pos = 0;
-#ifndef IEEE80211_MSSE2
 	int j;
-#endif
 
 	// circular buffer with the last ntraceback paths
 	d_store_pos = (d_store_pos + 1) % ntraceback;
@@ -342,42 +333,6 @@ viterbi_decoder::viterbi_get_output_generic(unsigned char *mm0,
 	return bestmetric;
 }
 
-uint8_t*
-viterbi_decoder::depuncture(uint8_t *in) {
-
-	int count;
-	int n_cbps = d_ofdm->n_cbps;
-	uint8_t *depunctured;
-
-	if (d_ntraceback == 5) {
-		count = d_frame->n_sym * n_cbps;
-		depunctured = in;
-
-	} else {
-		depunctured = d_depunctured;
-		count = 0;
-		for(int i = 0; i < d_frame->n_sym; i++) {
-			for(int k = 0; k < n_cbps; k++) {
-				while (d_depuncture_pattern[count % (2 * d_k)] == 0) {
-					depunctured[count] = 2;
-					count++;
-				}
-
-				// Insert received bits
-				depunctured[count] = in[i * n_cbps + k];
-				count++;
-
-				while (d_depuncture_pattern[count % (2 * d_k)] == 0) {
-					depunctured[count] = 2;
-					count++;
-				}
-			}
-		}
-	}
-
-	return depunctured;
-}
-
 uint8_t*
 viterbi_decoder::decode(ofdm_param *ofdm, frame_param *frame, uint8_t *in) {
 
@@ -469,44 +424,3 @@ viterbi_decoder::viterbi_chunks_init_generic() {
 		}
 	}
 }
-
-
-/* Parity lookup table */
-const unsigned char viterbi_decoder::PARTAB[256] = {
-	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,
-};
-
-const unsigned char viterbi_decoder::PUNCTURE_1_2[2] = {1, 1};
-const unsigned char viterbi_decoder::PUNCTURE_2_3[4] = {1, 1, 1, 0};
-const unsigned char viterbi_decoder::PUNCTURE_3_4[6] = {1, 1, 1, 0, 0, 1};

lib/viterbi_decoder/viterbi_decoder_generic.h

@@ -17,38 +17,24 @@
 #ifndef INCLUDED_IEEE802_11_VITERBI_DECODER_GENERIC_H
 #define INCLUDED_IEEE802_11_VITERBI_DECODER_GENERIC_H
 
-#include "utils.h"
+#include "base.h"
 
 namespace gr {
 namespace ieee802_11 {
 
-// Maximum number of traceback bytes
-#define TRACEBACK_MAX 24
-
 /* This Viterbi decoder was taken from the gr-dvbt module of
  * GNU Radio. It is an SSE2 version of the Viterbi Decoder
  * created by Phil Karn. The SSE2 version was made by Bogdan
  * Diaconescu. For more info see: gr-dvbt/lib/d_viterbi.h
  */
-class viterbi_decoder
+class viterbi_decoder : public base
 {
 public:
 
-	viterbi_decoder();
+	virtual uint8_t* decode(ofdm_param *ofdm, frame_param *frame, uint8_t *in);
-	virtual ~viterbi_decoder();
-
-	uint8_t* decode(ofdm_param *ofdm, frame_param *frame, uint8_t *in);
 
 private:
 
-	// Position in circular buffer where the current decoded byte is stored
-	int d_store_pos;
-	// Metrics for each state
-	unsigned char d_mmresult[64] __attribute__((aligned(16)));
-	// Paths for each state
-	unsigned char d_ppresult[TRACEBACK_MAX][64] __attribute__((aligned(16)));
-
-
 	union branchtab27 {
 		unsigned char c[32];
 	} d_branchtab27_generic[2];
@@ -58,22 +44,7 @@ private:
 	unsigned char d_path0_generic[64] __attribute__ ((aligned(16)));
 	unsigned char d_path1_generic[64] __attribute__ ((aligned(16)));
 
-	int d_ntraceback;
-	int d_k;
-	ofdm_param *d_ofdm;
-	frame_param *d_frame;
-	const unsigned char *d_depuncture_pattern;
-
-	uint8_t d_depunctured[MAX_ENCODED_BITS];
-	uint8_t d_decoded[MAX_ENCODED_BITS * 3 / 4];
-
-	static const unsigned char PARTAB[256];
-	static const unsigned char PUNCTURE_1_2[2];
-	static const unsigned char PUNCTURE_2_3[4];
-	static const unsigned char PUNCTURE_3_4[6];
-
 	void reset();
-	uint8_t* depuncture(uint8_t *in);
 
 	void viterbi_chunks_init_generic();
 	void viterbi_butterfly2_generic(unsigned char *symbols,

lib/viterbi_decoder/viterbi_decoder_x86.cc

@@ -27,7 +27,7 @@
  * Some modifications from original Karn code by Matt Ettus
  * Major modifications by adding SSE2 code by Bogdan Diaconescu
  */
-#include "viterbi_decoder.h"
+#include "viterbi_decoder_x86.h"
 #include <cstring>
 #include <iostream>
 
@@ -82,14 +82,6 @@
 
 using namespace gr::ieee802_11;
 
-
-viterbi_decoder::viterbi_decoder() :
-	d_store_pos(0) {
-}
-
-viterbi_decoder::~viterbi_decoder() {
-}
-
 void
 viterbi_decoder::viterbi_butterfly2_sse2(unsigned char *symbols,
 		__m128i *mm0, __m128i *mm1, __m128i *pp0, __m128i *pp1) {
@@ -205,9 +197,6 @@ viterbi_decoder::viterbi_get_output_sse2(__m128i *mm0, __m128i *pp0,
 	int bestmetric, minmetric;
 	int beststate = 0;
 	int pos = 0;
-#ifndef IEEE80211_MSSE2
-	int j;
-#endif
 
 	// circular buffer with the last ntraceback paths
 	d_store_pos = (d_store_pos + 1) % ntraceback;
@@ -253,41 +242,6 @@ viterbi_decoder::viterbi_get_output_sse2(__m128i *mm0, __m128i *pp0,
 	return bestmetric;
 }
 
-uint8_t*
-viterbi_decoder::depuncture(uint8_t *in) {
-
-	int count;
-	int n_cbps = d_ofdm->n_cbps;
-	uint8_t *depunctured;
-
-	if (d_ntraceback == 5) {
-		count = d_frame->n_sym * n_cbps;
-		depunctured = in;
-
-	} else {
-		depunctured = d_depunctured;
-		count = 0;
-		for(int i = 0; i < d_frame->n_sym; i++) {
-			for(int k = 0; k < n_cbps; k++) {
-				while (d_depuncture_pattern[count % (2 * d_k)] == 0) {
-					depunctured[count] = 2;
-					count++;
-				}
-
-				// Insert received bits
-				depunctured[count] = in[i * n_cbps + k];
-				count++;
-
-				while (d_depuncture_pattern[count % (2 * d_k)] == 0) {
-					depunctured[count] = 2;
-					count++;
-				}
-			}
-		}
-	}
-
-	return depunctured;
-}
 
 uint8_t*
 viterbi_decoder::decode(ofdm_param *ofdm, frame_param *frame, uint8_t *in) {
@@ -379,44 +333,3 @@ viterbi_decoder::viterbi_chunks_init_sse2() {
 		}
 	}
 }
-
-
-/* Parity lookup table */
-const unsigned char viterbi_decoder::PARTAB[256] = {
-	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,
-};
-
-const unsigned char viterbi_decoder::PUNCTURE_1_2[2] = {1, 1};
-const unsigned char viterbi_decoder::PUNCTURE_2_3[4] = {1, 1, 1, 0};
-const unsigned char viterbi_decoder::PUNCTURE_3_4[6] = {1, 1, 1, 0, 0, 1};

lib/viterbi_decoder/viterbi_decoder_x86.h

@@ -18,38 +18,24 @@
 #define INCLUDED_IEEE802_11_VITERBI_DECODER_X86_H
 
 #include <xmmintrin.h>
-#include "utils.h"
+#include "base.h"
 
 namespace gr {
 namespace ieee802_11 {
 
-// Maximum number of traceback bytes
-#define TRACEBACK_MAX 24
-
 /* This Viterbi decoder was taken from the gr-dvbt module of
  * GNU Radio. It is an SSE2 version of the Viterbi Decoder
  * created by Phil Karn. The SSE2 version was made by Bogdan
  * Diaconescu. For more info see: gr-dvbt/lib/d_viterbi.h
  */
-class viterbi_decoder
+class viterbi_decoder : public base
 {
 public:
 
-	viterbi_decoder();
+	virtual uint8_t* decode(ofdm_param *ofdm, frame_param *frame, uint8_t *in);
-	virtual ~viterbi_decoder();
-
-	uint8_t* decode(ofdm_param *ofdm, frame_param *frame, uint8_t *in);
 
 private:
 
-	// Position in circular buffer where the current decoded byte is stored
-	int d_store_pos;
-	// Metrics for each state
-	unsigned char d_mmresult[64] __attribute__((aligned(16)));
-	// Paths for each state
-	unsigned char d_ppresult[TRACEBACK_MAX][64] __attribute__((aligned(16)));
-
-
 	union branchtab27 {
 		unsigned char c[32];
 		__m128i v[2];
@@ -60,22 +46,7 @@ private:
 	__m128i d_path0[4] __attribute__ ((aligned(16)));
 	__m128i d_path1[4] __attribute__ ((aligned(16)));
 
-	int d_ntraceback;
+	virtual void reset();
-	int d_k;
-	ofdm_param *d_ofdm;
-	frame_param *d_frame;
-	const unsigned char *d_depuncture_pattern;
-
-	uint8_t d_depunctured[MAX_ENCODED_BITS];
-	uint8_t d_decoded[MAX_ENCODED_BITS * 3 / 4];
-
-	static const unsigned char PARTAB[256];
-	static const unsigned char PUNCTURE_1_2[2];
-	static const unsigned char PUNCTURE_2_3[4];
-	static const unsigned char PUNCTURE_3_4[6];
-
-	void reset();
-	uint8_t* depuncture(uint8_t *in);
 
 	void viterbi_chunks_init_sse2();
 	void viterbi_butterfly2_sse2(unsigned char *symbols,