[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Commit-gnuradio] [gnuradio] 01/03: gr-dtv: Add generic version of DVB-T
|
From: |
git |
|
Subject: |
[Commit-gnuradio] [gnuradio] 01/03: gr-dtv: Add generic version of DVB-T Viterbi decoder for non-x86 platforms. |
|
Date: |
Wed, 14 Oct 2015 02:48:38 +0000 (UTC) |
This is an automated email from the git hooks/post-receive script.
jcorgan pushed a commit to branch master
in repository gnuradio.
commit 0288cd0a351c74bfd604fbd8415a2a32135f6bb9
Author: Ron Economos <address@hidden>
Date: Tue Oct 13 14:47:54 2015 -0700
gr-dtv: Add generic version of DVB-T Viterbi decoder for non-x86 platforms.
---
gr-dtv/CMakeLists.txt | 4 -
gr-dtv/lib/CMakeLists.txt | 8 +-
gr-dtv/lib/dvbt/dvbt_viterbi_decoder_impl.cc | 270 +++++++++++++++++++++++++++
gr-dtv/lib/dvbt/dvbt_viterbi_decoder_impl.h | 28 ++-
4 files changed, 304 insertions(+), 6 deletions(-)
diff --git a/gr-dtv/CMakeLists.txt b/gr-dtv/CMakeLists.txt
index 3a0d116..fc7ab56 100644
--- a/gr-dtv/CMakeLists.txt
+++ b/gr-dtv/CMakeLists.txt
@@ -27,11 +27,7 @@ include(GrBoost)
########################################################################
include(GrComponent)
-include (CheckCCompilerFlag)
-CHECK_C_COMPILER_FLAG ("-msse2" SSE2_SUPPORTED)
-
GR_REGISTER_COMPONENT("gr-dtv" ENABLE_GR_DTV
- SSE2_SUPPORTED
Boost_FOUND
ENABLE_GNURADIO_RUNTIME
ENABLE_GR_ANALOG
diff --git a/gr-dtv/lib/CMakeLists.txt b/gr-dtv/lib/CMakeLists.txt
index f044469..868205c 100644
--- a/gr-dtv/lib/CMakeLists.txt
+++ b/gr-dtv/lib/CMakeLists.txt
@@ -127,7 +127,13 @@ list(APPEND dtv_libs
${VOLK_LIBRARIES}
)
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -msse2")
+include (CheckCCompilerFlag)
+CHECK_C_COMPILER_FLAG ("-msse2" SSE2_SUPPORTED)
+
+if(SSE2_SUPPORTED)
+ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -msse2")
+ ADD_DEFINITIONS(-DDTV_SSE2)
+endif(SSE2_SUPPORTED)
#Add Windows DLL resource file if using MSVC
if(MSVC)
diff --git a/gr-dtv/lib/dvbt/dvbt_viterbi_decoder_impl.cc
b/gr-dtv/lib/dvbt/dvbt_viterbi_decoder_impl.cc
index 4f2362c..3b0f9fd 100644
--- a/gr-dtv/lib/dvbt/dvbt_viterbi_decoder_impl.cc
+++ b/gr-dtv/lib/dvbt/dvbt_viterbi_decoder_impl.cc
@@ -70,22 +70,40 @@ namespace gr {
1, 0, 0, 1, 0, 1, 1, 0,
};
+#ifdef DTV_SSE2
__m128i dvbt_viterbi_decoder_impl::d_metric0[4] __attribute__
((aligned(16)));
__m128i dvbt_viterbi_decoder_impl::d_metric1[4] __attribute__
((aligned(16)));
__m128i dvbt_viterbi_decoder_impl::d_path0[4] __attribute__
((aligned(16)));
__m128i dvbt_viterbi_decoder_impl::d_path1[4] __attribute__
((aligned(16)));
+#else
+ unsigned char dvbt_viterbi_decoder_impl::d_metric0_generic[64]
__attribute__ ((aligned(16)));
+ unsigned char dvbt_viterbi_decoder_impl::d_metric1_generic[64]
__attribute__ ((aligned(16)));
+ unsigned char dvbt_viterbi_decoder_impl::d_path0_generic[64] __attribute__
((aligned(16)));
+ unsigned char dvbt_viterbi_decoder_impl::d_path1_generic[64] __attribute__
((aligned(16)));
+#endif
+#ifdef DTV_SSE2
branchtab27 dvbt_viterbi_decoder_impl::Branchtab27_sse2[2] __attribute__
((aligned(16)));
+#else
+ branchtab27 dvbt_viterbi_decoder_impl::Branchtab27_generic[2]
__attribute__ ((aligned(16)));
+#endif
unsigned char dvbt_viterbi_decoder_impl::mmresult[64]
__attribute__((aligned(16)));
unsigned char dvbt_viterbi_decoder_impl::ppresult[TRACEBACK_MAX][64]
__attribute__((aligned(16)));
+#ifdef DTV_SSE2
void
dvbt_viterbi_decoder_impl::dvbt_viterbi_chunks_init_sse2(__m128i *mm0,
__m128i *pp0)
{
+#else
+ void
+ dvbt_viterbi_decoder_impl::dvbt_viterbi_chunks_init_generic(unsigned char
*mm0, unsigned char *pp0)
+ {
+#endif
// Initialize starting metrics to prefer 0 state
int i, j;
+#ifdef DTV_SSE2
for (i = 0; i < 4; i++) {
mm0[i] = _mm_setzero_si128();
pp0[i] = _mm_setzero_si128();
@@ -96,6 +114,18 @@ namespace gr {
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;
}
+#else
+ for (i = 0; i < 64; i++) {
+ mm0[i] = 0;
+ pp0[i] = 0;
+ }
+
+ int polys[2] = { POLYA, POLYB };
+ for (i = 0; i < 32; i++) {
+ Branchtab27_generic[0].c[i] = (polys[0] < 0) ^ d_Partab[(2*i) &
abs(polys[0])] ? 1 : 0;
+ Branchtab27_generic[1].c[i] = (polys[1] < 0) ^ d_Partab[(2*i) &
abs(polys[1])] ? 1 : 0;
+ }
+#endif
for (i = 0; i < 64; i++) {
mmresult[i] = 0;
@@ -105,6 +135,7 @@ namespace gr {
}
}
+#ifdef DTV_SSE2
void
dvbt_viterbi_decoder_impl::dvbt_viterbi_butterfly2_sse2(unsigned char
*symbols, __m128i *mm0, __m128i *mm1, __m128i *pp0, __m128i *pp1)
{
@@ -213,24 +244,235 @@ namespace gr {
path1[2*i+1] = _mm_unpackhi_epi8(tmp0, tmp1);
}
}
+#else
+ void
+ dvbt_viterbi_decoder_impl::dvbt_viterbi_butterfly2_generic(unsigned char
*symbols, unsigned char *mm0, unsigned char *mm1, unsigned char *pp0, unsigned
char *pp1)
+ {
+ int i, j, k;
+ unsigned char *metric0, *metric1;
+ unsigned char *path0, *path1;
+
+ metric0 = mm0;
+ path0 = pp0;
+ metric1 = mm1;
+ path1 = pp1;
+
+ // Operate on 4 symbols (2 bits) at a time
+
+ unsigned char m0[16], m1[16], m2[16], m3[16], decision0[16],
decision1[16], survivor0[16], survivor1[16];
+ unsigned char metsv[16], metsvm[16];
+ unsigned char shift0[16], shift1[16];
+ unsigned char tmp0[16], tmp1[16];
+ unsigned char sym0v[16], sym1v[16];
+ unsigned short simd_epi16;
+
+ for (j = 0; j < 16; j++) {
+ sym0v[j] = symbols[0];
+ sym1v[j] = symbols[1];
+ }
+
+ for (i = 0; i < 2; i++) {
+ if (symbols[0] == 2) {
+ for (j = 0; j < 16; j++) {
+ metsvm[j] = Branchtab27_generic[1].c[(i*16) + j] ^ sym1v[j];
+ metsv[j] = 1 - metsvm[j];
+ }
+ }
+ else if (symbols[1] == 2) {
+ for (j = 0; j < 16; j++) {
+ metsvm[j] = Branchtab27_generic[0].c[(i*16) + j] ^ sym0v[j];
+ metsv[j] = 1 - metsvm[j];
+ }
+ }
+ else {
+ for (j = 0; j < 16; j++) {
+ metsvm[j] = (Branchtab27_generic[0].c[(i*16) + j] ^ sym0v[j]) +
(Branchtab27_generic[1].c[(i*16) + j] ^ sym1v[j]);
+ metsv[j] = 2 - metsvm[j];
+ }
+ }
+
+ for (j = 0; j < 16; j++) {
+ m0[j] = metric0[(i*16) + j] + metsv[j];
+ m1[j] = metric0[((i+2)*16) + j] + metsvm[j];
+ m2[j] = metric0[(i*16) + j] + metsvm[j];
+ m3[j] = metric0[((i+2)*16) + j] + metsv[j];
+ }
+
+ for (j = 0; j < 16; j++) {
+ decision0[j] = ((m0[j] - m1[j]) > 0) ? 0xff : 0x0;
+ decision1[j] = ((m2[j] - m3[j]) > 0) ? 0xff : 0x0;
+ survivor0[j] = (decision0[j] & m0[j]) | ((~decision0[j]) & m1[j]);
+ survivor1[j] = (decision1[j] & m2[j]) | ((~decision1[j]) & m3[j]);
+ }
+
+ for (j = 0; j < 16; j += 2) {
+ simd_epi16 = path0[(i*16) + j];
+ simd_epi16 |= path0[(i*16) + (j+1)] << 8;
+ simd_epi16 <<= 1;
+ shift0[j] = simd_epi16;
+ shift0[j+1] = simd_epi16 >> 8;
+
+ simd_epi16 = path0[((i+2)*16) + j];
+ simd_epi16 |= path0[((i+2)*16) + (j+1)] << 8;
+ simd_epi16 <<= 1;
+ shift1[j] = simd_epi16;
+ shift1[j+1] = simd_epi16 >> 8;
+ }
+ for (j = 0; j < 16; j++) {
+ shift1[j] = shift1[j] + 1;
+ }
+
+ for (j = 0, k = 0; j < 16; j += 2, k++) {
+ metric1[(2*i*16) + j] = survivor0[k];
+ metric1[(2*i*16) + (j+1)] = survivor1[k];
+ }
+ for (j = 0; j < 16; j++) {
+ tmp0[j] = (decision0[j] & shift0[j]) | ((~decision0[j]) & shift1[j]);
+ }
+
+ for (j = 0, k = 8; j < 16; j += 2, k++) {
+ metric1[((2*i+1)*16) + j] = survivor0[k];
+ metric1[((2*i+1)*16) + (j+1)] = survivor1[k];
+ }
+ for (j = 0; j < 16; j++) {
+ tmp1[j] = (decision1[j] & shift0[j]) | ((~decision1[j]) & shift1[j]);
+ }
+
+ for (j = 0, k = 0; j < 16; j += 2, k++) {
+ path1[(2*i*16) + j] = tmp0[k];
+ path1[(2*i*16) + (j+1)] = tmp1[k];
+ }
+ for (j = 0, k = 8; j < 16; j += 2, k++) {
+ path1[((2*i+1)*16) + j] = tmp0[k];
+ path1[((2*i+1)*16) + (j+1)] = tmp1[k];
+ }
+ }
+
+ metric0 = mm1;
+ path0 = pp1;
+ metric1 = mm0;
+ path1 = pp0;
+
+ for (j = 0; j < 16; j++) {
+ sym0v[j] = symbols[2];
+ sym1v[j] = symbols[3];
+ }
+
+ for (i = 0; i < 2; i++) {
+ if (symbols[2] == 2) {
+ for (j = 0; j < 16; j++) {
+ metsvm[j] = Branchtab27_generic[1].c[(i*16) + j] ^ sym1v[j];
+ metsv[j] = 1 - metsvm[j];
+ }
+ }
+ else if (symbols[3] == 2) {
+ for (j = 0; j < 16; j++) {
+ metsvm[j] = Branchtab27_generic[0].c[(i*16) + j] ^ sym0v[j];
+ metsv[j] = 1 - metsvm[j];
+ }
+ }
+ else {
+ for (j = 0; j < 16; j++) {
+ metsvm[j] = (Branchtab27_generic[0].c[(i*16) + j] ^ sym0v[j]) +
(Branchtab27_generic[1].c[(i*16) + j] ^ sym1v[j]);
+ metsv[j] = 2 - metsvm[j];
+ }
+ }
+
+ for (j = 0; j < 16; j++) {
+ m0[j] = metric0[(i*16) + j] + metsv[j];
+ m1[j] = metric0[((i+2)*16) + j] + metsvm[j];
+ m2[j] = metric0[(i*16) + j] + metsvm[j];
+ m3[j] = metric0[((i+2)*16) + j] + metsv[j];
+ }
+
+ for (j = 0; j < 16; j++) {
+ decision0[j] = ((m0[j] - m1[j]) > 0) ? 0xff : 0x0;
+ decision1[j] = ((m2[j] - m3[j]) > 0) ? 0xff : 0x0;
+ survivor0[j] = (decision0[j] & m0[j]) | ((~decision0[j]) & m1[j]);
+ survivor1[j] = (decision1[j] & m2[j]) | ((~decision1[j]) & m3[j]);
+ }
+
+ for (j = 0; j < 16; j += 2) {
+ simd_epi16 = path0[(i*16) + j];
+ simd_epi16 |= path0[(i*16) + (j+1)] << 8;
+ simd_epi16 <<= 1;
+ shift0[j] = simd_epi16;
+ shift0[j+1] = simd_epi16 >> 8;
+
+ simd_epi16 = path0[((i+2)*16) + j];
+ simd_epi16 |= path0[((i+2)*16) + (j+1)] << 8;
+ simd_epi16 <<= 1;
+ shift1[j] = simd_epi16;
+ shift1[j+1] = simd_epi16 >> 8;
+ }
+ for (j = 0; j < 16; j++) {
+ shift1[j] = shift1[j] + 1;
+ }
+
+ for (j = 0, k = 0; j < 16; j += 2, k++) {
+ metric1[(2*i*16) + j] = survivor0[k];
+ metric1[(2*i*16) + (j+1)] = survivor1[k];
+ }
+ for (j = 0; j < 16; j++) {
+ tmp0[j] = (decision0[j] & shift0[j]) | ((~decision0[j]) & shift1[j]);
+ }
+
+ for (j = 0, k = 8; j < 16; j += 2, k++) {
+ metric1[((2*i+1)*16) + j] = survivor0[k];
+ metric1[((2*i+1)*16) + (j+1)] = survivor1[k];
+ }
+ for (j = 0; j < 16; j++) {
+ tmp1[j] = (decision1[j] & shift0[j]) | ((~decision1[j]) & shift1[j]);
+ }
+
+ for (j = 0, k = 0; j < 16; j += 2, k++) {
+ path1[(2*i*16) + j] = tmp0[k];
+ path1[(2*i*16) + (j+1)] = tmp1[k];
+ }
+ for (j = 0, k = 8; j < 16; j += 2, k++) {
+ path1[((2*i+1)*16) + j] = tmp0[k];
+ path1[((2*i+1)*16) + (j+1)] = tmp1[k];
+ }
+ }
+ }
+#endif
+
+#ifdef DTV_SSE2
unsigned char
dvbt_viterbi_decoder_impl::dvbt_viterbi_get_output_sse2(__m128i *mm0,
__m128i *pp0, int ntraceback, unsigned char *outbuf)
{
+#else
+ unsigned char
+ dvbt_viterbi_decoder_impl::dvbt_viterbi_get_output_generic(unsigned char
*mm0, unsigned char *pp0, int ntraceback, unsigned char *outbuf)
+ {
+#endif
// Find current best path
int i;
int bestmetric, minmetric;
int beststate = 0;
int pos = 0;
+#ifndef DTV_SSE2
+ int j;
+#endif
// Implement a circular buffer with the last ntraceback paths
store_pos = (store_pos + 1) % ntraceback;
+#ifdef DTV_SSE2
// 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]);
}
+#else
+ for (i = 0; i < 4; i++) {
+ for (j = 0; j < 16; j++) {
+ mmresult[(i*16) + j] = mm0[(i*16) + j];
+ ppresult[store_pos][(i*16) + j] = pp0[(i*16) + j];
+ }
+ }
+#endif
// Find out the best final state
bestmetric = mmresult[beststate];
@@ -258,12 +500,21 @@ namespace gr {
// Store output byte
*outbuf = ppresult[pos][beststate];
+#ifdef DTV_SSE2
// 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));
}
+#else
+ for (i = 0; i < 4; i++) {
+ for (j = 0; j < 16; j++) {
+ pp0[(i*16) + j] = 0;
+ mm0[(i*16) + j] = mm0[(i*16) + j] - minmetric;
+ }
+ }
+#endif
return bestmetric;
}
@@ -357,7 +608,12 @@ namespace gr {
mettab[1][0] = 0;
mettab[1][1] = 1;
+#ifdef DTV_SSE2
dvbt_viterbi_chunks_init_sse2(d_metric0, d_path0);
+#else
+ dvbt_viterbi_chunks_init_generic(d_metric0_generic, d_path0_generic);
+#endif
+
}
/*
@@ -404,7 +660,12 @@ namespace gr {
if (tags.size()) {
d_init = 0;
+
+#ifdef DTV_SSE2
dvbt_viterbi_chunks_init_sse2(d_metric0, d_path0);
+#else
+ dvbt_viterbi_chunks_init_generic(d_metric0_generic, d_path0_generic);
+#endif
if (tags[0].offset - nread) {
consume_each(tags[0].offset - nread);
@@ -443,12 +704,21 @@ namespace gr {
*/
for (int in_count = 0; in_count < d_nbits; in_count++) {
if ((in_count % 4) == 0) { // 0 or 3
+
+#ifdef DTV_SSE2
dvbt_viterbi_butterfly2_sse2(&d_inbits[in_count & 0xfffffffc],
d_metric0, d_metric1, d_path0, d_path1);
+#else
+ dvbt_viterbi_butterfly2_generic(&d_inbits[in_count &
0xfffffffc], d_metric0_generic, d_metric1_generic, d_path0_generic,
d_path1_generic);
+#endif
if ((in_count > 0) && (in_count % 16) == 8) { // 8 or 11
unsigned char c;
+#ifdef DTV_SSE2
dvbt_viterbi_get_output_sse2(d_metric0, d_path0, d_ntraceback,
&c);
+#else
+ dvbt_viterbi_get_output_generic(d_metric0_generic,
d_path0_generic, d_ntraceback, &c);
+#endif
if (d_init == 0) {
if (out_count >= d_ntraceback) {
diff --git a/gr-dtv/lib/dvbt/dvbt_viterbi_decoder_impl.h
b/gr-dtv/lib/dvbt/dvbt_viterbi_decoder_impl.h
index 8870a79..22b040c 100644
--- a/gr-dtv/lib/dvbt/dvbt_viterbi_decoder_impl.h
+++ b/gr-dtv/lib/dvbt/dvbt_viterbi_decoder_impl.h
@@ -23,7 +23,10 @@
#include <gnuradio/dtv/dvbt_viterbi_decoder.h>
#include "dvbt_configure.h"
+
+#ifdef DTV_SSE2
#include <xmmintrin.h>
+#endif
/* The two generator polynomials for the NASA Standard K=7 code.
* Since these polynomials are known to be optimal for this constraint
@@ -35,10 +38,16 @@
// Maximum number of traceback bytes
#define TRACEBACK_MAX 24
+#ifdef DTV_SSE2
union branchtab27 {
unsigned char c[32];
__m128i v[2];
};
+#else
+struct branchtab27 {
+ unsigned char c[32];
+};
+#endif
namespace gr {
namespace dtv {
@@ -56,12 +65,23 @@ namespace gr {
static const unsigned char d_puncture_7_8[];
static const unsigned char d_Partab[];
+#ifdef DTV_SSE2
static __m128i d_metric0[4];
static __m128i d_metric1[4];
static __m128i d_path0[4];
static __m128i d_path1[4];
-
+#else
+ static unsigned char d_metric0_generic[64];
+ static unsigned char d_metric1_generic[64];
+ static unsigned char d_path0_generic[64];
+ static unsigned char d_path1_generic[64];
+#endif
+
+#ifdef DTV_SSE2
static branchtab27 Branchtab27_sse2[2];
+#else
+ static branchtab27 Branchtab27_generic[2];
+#endif
// Metrics for each state
static unsigned char mmresult[64];
@@ -101,9 +121,15 @@ namespace gr {
// Position in circular buffer where the current decoded byte is stored
int store_pos;
+#ifdef DTV_SSE2
void dvbt_viterbi_chunks_init_sse2(__m128i *mm0, __m128i *pp0);
void dvbt_viterbi_butterfly2_sse2(unsigned char *symbols, __m128i m0[],
__m128i m1[], __m128i p0[], __m128i p1[]);
unsigned char dvbt_viterbi_get_output_sse2(__m128i *mm0, __m128i *pp0,
int ntraceback, unsigned char *outbuf);
+#else
+ void dvbt_viterbi_chunks_init_generic(unsigned char *mm0, unsigned char
*pp0);
+ void dvbt_viterbi_butterfly2_generic(unsigned char *symbols, unsigned
char m0[], unsigned char m1[], unsigned char p0[], unsigned char p1[]);
+ unsigned char dvbt_viterbi_get_output_generic(unsigned char *mm0,
unsigned char *pp0, int ntraceback, unsigned char *outbuf);
+#endif
public:
dvbt_viterbi_decoder_impl(dvb_constellation_t constellation, \