Add LDPC shared lib doc

openair1/PHY/CODING/DOC/LDPCImplementation.md

+#LDPC coder/decoder implementation
+The LDPC coder and decoder are implemented in a shared library, dynamically loaded at run-time using the [oai shared library loader](file://../../../../common/utils/DOC/loader.md). The code loading the LDPC library is in [nrLDPC_load.c](file://../nrLDPC_load.c), in function `load_nrLDPClib`, which must be called at init time.
+
+## Selecting the LDPC library at run time
+
+By default the function `int load_nrLDPClib(void)` looks for `libldpc.so`, this default behavior can be changed using the oai loader configuration options in the configuration file or from the command line as shown below:
+
+>loading `libldpc_optim8seg.so` instead of `libldpc.so`
+
+```
+./nr-softmodem -O libconfig:gnb.band78.tm1.106PRB.usrpx300.conf:dbgl5  --loader.ldpc.shlibversion _optim8seg
+.......................
+[CONFIG] loader.ldpc.shlibversion set to default value ""
+[LIBCONFIG] loader.ldpc: 2/2 parameters successfully set, (1 to default value)
+[CONFIG] shlibversion set to  _optim8seg from command line
+[CONFIG] loader.ldpc 1 options set from command line
+[LOADER] library libldpc_optim8seg.so successfully loaded
+........................
+```
+
+Today, this mechanism is not available in the `ldpctest` phy simulator which doesn't initialize the [configuration module](file://../../../../common/config/DOC/config.md). loads `libldpc.so` and `libldpc_orig.so` to compare the performance of the two implementations.
+
+###LDPC libraries
+Libraries implementing the LDPC algorithms must be named `libldpc<_version>.so`, they must implement two functions: `nrLDPC_decod` and `nrLDPC_encod`. The prototypes for these functions is defined in [nrLDPC_defs.h](file://nrLDPC_defs.h).
+
+[oai Wikis home](https://gitlab.eurecom.fr/oai/openairinterface5g/wikis/home)

openair1/PHY/CODING/nrLDPC_encoder/ldpc_encoder_optim8seg.c

+/*
+ * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The OpenAirInterface Software Alliance licenses this file to You under
+ * the OAI Public License, Version 1.1  (the "License"); you may not use this file
+ * except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.openairinterface.org/?page_id=698
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *-------------------------------------------------------------------------------
+ * For more information about the OpenAirInterface (OAI) Software Alliance:
+ *      contact@openairinterface.org
+ */
+
+/*!\file ldpc_encoder2.c
+ * \brief Defines the optimized LDPC encoder
+ * \author Florian Kaltenberger, Raymond Knopp, Kien le Trung (Eurecom)
+ * \email openair_tech@eurecom.fr
+ * \date 27-03-2018
+ * \version 1.0
+ * \note
+ * \warning
+ */
+
+#include <stdlib.h>
+#include <math.h>
+#include <stdio.h>
+#include <string.h>
+#include <types.h>
+#include "assertions.h"
+#include "common/utils/LOG/log.h"
+#include "PHY/TOOLS/time_meas.h"
+#include "openair1/PHY/CODING/nrLDPC_defs.h"
+//#define DEBUG_LDPC
+#include "ldpc_encode_parity_check.c" 
+#include "ldpc_generate_coefficient.c"
+
+
+
+int nrLDPC_encod(unsigned char **test_input,unsigned char **channel_input,int Zc,int Kb,short block_length, short BG, encoder_implemparams_t *impp)
+{
+
+  short nrows=0,ncols=0;
+  int i,i1,j,rate=3;
+  int no_punctured_columns,removed_bit;
+  char temp;
+  int simd_size;
+
+#ifdef __AVX2__
+  __m256i shufmask = _mm256_set_epi64x(0x0303030303030303, 0x0202020202020202,0x0101010101010101, 0x0000000000000000);
+  __m256i andmask  = _mm256_set1_epi64x(0x0102040810204080);  // every 8 bits -> 8 bytes, pattern repeats.
+  __m256i zero256   = _mm256_setzero_si256();
+  __m256i masks[8];
+  register __m256i c256;
+  masks[0] = _mm256_set1_epi8(0x1);
+  masks[1] = _mm256_set1_epi8(0x2);
+  masks[2] = _mm256_set1_epi8(0x4);
+  masks[3] = _mm256_set1_epi8(0x8);
+  masks[4] = _mm256_set1_epi8(0x10);
+  masks[5] = _mm256_set1_epi8(0x20);
+  masks[6] = _mm256_set1_epi8(0x40);
+  masks[7] = _mm256_set1_epi8(0x80);
+#endif
+
+  AssertFatal((impp->n_segments>0&&impp->n_segments<=8),"0 < n_segments %d <= 8\n",impp->n_segments);
+
+  //determine number of bits in codeword
+  //if (block_length>3840)
+  if (BG==1)
+    {
+      nrows=46; //parity check bits
+      ncols=22; //info bits
+      rate=3;
+    }
+    //else if (block_length<=3840)
+   else if	(BG==2)
+    {
+      //BG=2;
+      nrows=42; //parity check bits
+      ncols=10; // info bits
+      rate=5;
+
+      }
+
+#ifdef DEBUG_LDPC
+  LOG_D(PHY,"ldpc_encoder_optim_8seg: BG %d, Zc %d, Kb %d, block_length %d, segments %d\n",BG,Zc,Kb,block_length,n_segments);
+  LOG_D(PHY,"ldpc_encoder_optim_8seg: PDU (seg 0) %x %x %x %x\n",test_input[0][0],test_input[0][1],test_input[0][2],test_input[0][3]);
+#endif
+
+  AssertFatal(Zc>0,"no valid Zc found for block length %d\n",block_length);
+
+  if ((Zc&31) > 0) simd_size = 16;
+  else          simd_size = 32;
+
+  unsigned char c[22*Zc] __attribute__((aligned(32))); //padded input, unpacked, max size
+  unsigned char d[46*Zc] __attribute__((aligned(32))); //coded parity part output, unpacked, max size
+
+  unsigned char c_extension[2*22*Zc*simd_size] __attribute__((aligned(32)));      //double size matrix of c
+
+  // calculate number of punctured bits
+  no_punctured_columns=(int)((nrows-2)*Zc+block_length-block_length*rate)/Zc;
+  removed_bit=(nrows-no_punctured_columns-2) * Zc+block_length-(int)(block_length*rate);
+  // printf("%d\n",no_punctured_columns);
+  // printf("%d\n",removed_bit);
+  // unpack input
+  memset(c,0,sizeof(unsigned char) * ncols * Zc);
+  memset(d,0,sizeof(unsigned char) * nrows * Zc);
+
+  if(impp->tinput != NULL) start_meas(impp->tinput);
+#if 0
+  for (i=0; i<block_length; i++) {
+    for (j=0; j<n_segments; j++) {
+
+      temp = (test_input[j][i/8]&(128>>(i&7)))>>(7-(i&7));
+      //printf("c(%d,%d)=%d\n",j,i,temp);
+      c[i] |= (temp << j);
+    }
+  }
+#else
+#ifdef __AVX2__
+  for (i=0; i<block_length>>5; i++) {
+    c256 = _mm256_and_si256(_mm256_cmpeq_epi8(_mm256_andnot_si256(_mm256_shuffle_epi8(_mm256_set1_epi32(((uint32_t*)test_input[0])[i]), shufmask),andmask),zero256),masks[0]);
+    for (j=1; j<impp->n_segments; j++) {
+      c256 = _mm256_or_si256(_mm256_and_si256(_mm256_cmpeq_epi8(_mm256_andnot_si256(_mm256_shuffle_epi8(_mm256_set1_epi32(((uint32_t*)test_input[j])[i]), shufmask),andmask),zero256),masks[j]),c256);
+    }
+    ((__m256i *)c)[i] = c256;
+  }
+
+  for (i=(block_length>>5)<<5;i<block_length;i++) {
+    for (j=0; j<impp->n_segments; j++) {
+
+      temp = (test_input[j][i/8]&(128>>(i&7)))>>(7-(i&7));
+      //printf("c(%d,%d)=%d\n",j,i,temp);
+      c[i] |= (temp << j);
+    }
+  }
+#else
+  AssertFatal(1==0,"Need AVX2 for this\n");
+#endif
+#endif
+
+  if(impp->tinput != NULL) stop_meas(impp->tinput);
+
+  if ((BG==1 && Zc>176) || (BG==2 && Zc>64)) { 
+    // extend matrix
+    if(impp->tprep != NULL) start_meas(impp->tprep);
+    for (i1=0; i1 < ncols; i1++)
+      {
+	memcpy(&c_extension[2*i1*Zc], &c[i1*Zc], Zc*sizeof(unsigned char));
+	memcpy(&c_extension[(2*i1+1)*Zc], &c[i1*Zc], Zc*sizeof(unsigned char));
+      }
+    for (i1=1;i1<simd_size;i1++) {
+      memcpy(&c_extension[(2*ncols*Zc*i1)], &c_extension[i1], (2*ncols*Zc*sizeof(unsigned char))-i1);
+      //    memset(&c_extension[(2*ncols*Zc*i1)],0,i1);
+      /*
+	printf("shift %d: ",i1);
+	for (int j=0;j<64;j++) printf("%d ",c_extension[(2*ncols*Zc*i1)+j]);
+	printf("\n");
+      */
+    }
+    if(impp->tprep != NULL) stop_meas(impp->tprep);
+    //parity check part
+    if(impp->tparity != NULL) start_meas(impp->tparity);
+    encode_parity_check_part_optim(c_extension, d, BG, Zc, Kb);
+    if(impp->tparity != NULL) stop_meas(impp->tparity);
+  }
+  else {
+    if (encode_parity_check_part_orig(c, d, BG, Zc, Kb, block_length)!=0) {
+      printf("Problem with encoder\n");
+      return(-1);
+    }
+  }
+  if(impp->toutput != NULL) start_meas(impp->toutput);
+  // information part and puncture columns
+  /*
+  memcpy(&channel_input[0], &c[2*Zc], (block_length-2*Zc)*sizeof(unsigned char));
+  memcpy(&channel_input[block_length-2*Zc], &d[0], ((nrows-no_punctured_columns) * Zc-removed_bit)*sizeof(unsigned char));
+  */
+#ifdef __AVX2__
+  if ((((2*Zc)&31) == 0) && (((block_length-(2*Zc))&31) == 0)) {
+    //AssertFatal(((2*Zc)&31) == 0,"2*Zc needs to be a multiple of 32 for now\n");
+    //AssertFatal(((block_length-(2*Zc))&31) == 0,"block_length-(2*Zc) needs to be a multiple of 32 for now\n");
+    uint32_t l1 = (block_length-(2*Zc))>>5;
+    uint32_t l2 = ((nrows-no_punctured_columns) * Zc-removed_bit)>>5;
+    __m256i *c256p = (__m256i *)&c[2*Zc];
+    __m256i *d256p = (__m256i *)&d[0];
+    //  if (((block_length-(2*Zc))&31)>0) l1++;
+    
+    for (i=0;i<l1;i++)
+      for (j=0;j<impp->n_segments;j++) ((__m256i *)channel_input[j])[i] = _mm256_and_si256(_mm256_srai_epi16(c256p[i],j),masks[0]);
+    
+    //  if ((((nrows-no_punctured_columns) * Zc-removed_bit)&31)>0) l2++;
+    
+    for (i1=0;i1<l2;i1++,i++)
+      for (j=0;j<impp->n_segments;j++) ((__m256i *)channel_input[j])[i] = _mm256_and_si256(_mm256_srai_epi16(d256p[i1],j),masks[0]);
+  }
+  else {
+#ifdef DEBUG_LDPC
+  LOG_W(PHY,"using non-optimized version\n");
+#endif
+    // do non-SIMD version
+    for (i=0;i<(block_length-2*Zc);i++) 
+      for (j=0; j<impp->n_segments; j++)
+	channel_input[j][i] = (c[2*Zc+i]>>j)&1;
+    for (i=0;i<((nrows-no_punctured_columns) * Zc-removed_bit);i++)
+      for (j=0; j<impp->n_segments; j++)
+	channel_input[j][block_length-2*Zc+i] = (d[i]>>j)&1;
+    }
+
+#else
+    AssertFatal(1==0,"Need AVX2 for now\n");
+#endif
+
+  if(impp->toutput != NULL) stop_meas(impp->toutput);
+  return 0;
+}
+
+

openair1/PHY/CODING/nrLDPC_encoder/ldpc_encoder_optim8segmulti.c

+/*
+ * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The OpenAirInterface Software Alliance licenses this file to You under
+ * the OAI Public License, Version 1.1  (the "License"); you may not use this file
+ * except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.openairinterface.org/?page_id=698
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *-------------------------------------------------------------------------------
+ * For more information about the OpenAirInterface (OAI) Software Alliance:
+ *      contact@openairinterface.org
+ */
+
+/*!\file ldpc_encoder2.c
+ * \brief Defines the optimized LDPC encoder
+ * \author Florian Kaltenberger, Raymond Knopp, Kien le Trung (Eurecom)
+ * \email openair_tech@eurecom.fr
+ * \date 27-03-2018
+ * \version 1.0
+ * \note
+ * \warning
+ */
+
+#include <stdlib.h>
+#include <math.h>
+#include <stdio.h>
+#include <string.h>
+#include <types.h>
+#include "assertions.h"
+#include "common/utils/LOG/log.h"
+#include "PHY/TOOLS/time_meas.h"
+#include "openair1/PHY/CODING/nrLDPC_defs.h"
+
+//#define DEBUG_LDPC
+
+#include "ldpc_encode_parity_check.c"
+#include "ldpc_generate_coefficient.c"
+
+
+int nrLDPC_encod(unsigned char **test_input,unsigned char **channel_input,int Zc,int Kb,short block_length, short BG, encoder_implemparams_t *impp)
+{
+
+  short nrows=0,ncols=0;
+  int i,i1,j,rate=3;
+  int no_punctured_columns,removed_bit;
+  //Table of possible lifting sizes
+  char temp;
+  int simd_size;
+  unsigned int macro_segment, macro_segment_end;
+
+  
+  macro_segment = 8*impp->macro_num;
+  // macro_segment_end = (n_segments > 8*(macro_num+1)) ? 8*(macro_num+1) : n_segments;
+  macro_segment_end = macro_segment + (impp->n_segments > 8 ? 8 : impp->n_segments);
+  ///printf("macro_segment: %d\n", macro_segment);
+  ///printf("macro_segment_end: %d\n", macro_segment_end );
+
+#ifdef __AVX2__
+  __m256i shufmask = _mm256_set_epi64x(0x0303030303030303, 0x0202020202020202,0x0101010101010101, 0x0000000000000000);
+  __m256i andmask  = _mm256_set1_epi64x(0x0102040810204080);  // every 8 bits -> 8 bytes, pattern repeats.
+  __m256i zero256   = _mm256_setzero_si256();
+  __m256i masks[8];
+  register __m256i c256;
+  masks[0] = _mm256_set1_epi8(0x1);
+  masks[1] = _mm256_set1_epi8(0x2);
+  masks[2] = _mm256_set1_epi8(0x4);
+  masks[3] = _mm256_set1_epi8(0x8);
+  masks[4] = _mm256_set1_epi8(0x10);
+  masks[5] = _mm256_set1_epi8(0x20);
+  masks[6] = _mm256_set1_epi8(0x40);
+  masks[7] = _mm256_set1_epi8(0x80);
+#endif
+
+
+
+  //determine number of bits in codeword
+  if (BG==1)
+    {
+      nrows=46; //parity check bits
+      ncols=22; //info bits
+      rate=3;
+    }
+    else if (BG==2)
+    {
+      nrows=42; //parity check bits
+      ncols=10; // info bits
+      rate=5;
+    }
+
+#ifdef DEBUG_LDPC
+  LOG_D(PHY,"ldpc_encoder_optim_8seg: BG %d, Zc %d, Kb %d, block_length %d, segments %d\n",BG,Zc,Kb,block_length,n_segments);
+  LOG_D(PHY,"ldpc_encoder_optim_8seg: PDU (seg 0) %x %x %x %x\n",test_input[0][0],test_input[0][1],test_input[0][2],test_input[0][3]);
+#endif
+
+  AssertFatal(Zc>0,"no valid Zc found for block length %d\n",block_length);
+
+  if ((Zc&31) > 0) simd_size = 16;
+  else          simd_size = 32;
+
+  unsigned char c[22*Zc] __attribute__((aligned(32))); //padded input, unpacked, max size
+  unsigned char d[46*Zc] __attribute__((aligned(32))); //coded parity part output, unpacked, max size
+
+  unsigned char c_extension[2*22*Zc*simd_size] __attribute__((aligned(32)));      //double size matrix of c
+
+  // calculate number of punctured bits
+  no_punctured_columns=(int)((nrows-2)*Zc+block_length-block_length*rate)/Zc;
+  removed_bit=(nrows-no_punctured_columns-2) * Zc+block_length-(int)(block_length*rate);
+  //printf("%d\n",no_punctured_columns);
+  //printf("%d\n",removed_bit);
+  // unpack input
+  memset(c,0,sizeof(unsigned char) * ncols * Zc);
+  memset(d,0,sizeof(unsigned char) * nrows * Zc);
+
+  if(impp->tinput != NULL) start_meas(impp->tinput);
+#if 0
+  for (i=0; i<block_length; i++) {
+	//for (j=0; j<n_segments; j++) {
+    for (j=macro_segment; j < macro_segment_end; j++) {
+
+      temp = (test_input[j][i/8]&(1<<(i&7)))>>(i&7);
+      //printf("c(%d,%d)=%d\n",j,i,temp);
+      c[i] |= (temp << (j-macro_segment));
+    }
+  }
+#else
+#ifdef __AVX2__
+  for (i=0; i<block_length>>5; i++) {
+    c256 = _mm256_and_si256(_mm256_cmpeq_epi8(_mm256_andnot_si256(_mm256_shuffle_epi8(_mm256_set1_epi32(((uint32_t*)test_input[macro_segment])[i]), shufmask),andmask),zero256),masks[0]);
+    //for (j=1; j<n_segments; j++) {
+    for (j=macro_segment+1; j < macro_segment_end; j++) {    
+      c256 = _mm256_or_si256(_mm256_and_si256(_mm256_cmpeq_epi8(_mm256_andnot_si256(_mm256_shuffle_epi8(_mm256_set1_epi32(((uint32_t*)test_input[j])[i]), shufmask),andmask),zero256),masks[j-macro_segment]),c256);
+    }
+    ((__m256i *)c)[i] = c256;
+  }
+
+  for (i=(block_length>>5)<<5;i<block_length;i++) {
+    //for (j=0; j<n_segments; j++) {
+	  for (j=macro_segment; j < macro_segment_end; j++) {
+
+	    temp = (test_input[j][i/8]&(128>>(i&7)))>>(7-(i&7));
+      //printf("c(%d,%d)=%d\n",j,i,temp);
+      c[i] |= (temp << (j-macro_segment));
+    }
+  }
+#else
+  AssertFatal(1==0,"Need AVX2 for this\n");
+#endif
+#endif
+
+  if(impp->tinput != NULL) stop_meas(impp->tinput);
+
+  if ((BG==1 && Zc>176) || (BG==2 && Zc>64)) {
+    // extend matrix
+    if(impp->tprep != NULL) start_meas(impp->tprep);
+    for (i1=0; i1 < ncols; i1++)
+      {
+	memcpy(&c_extension[2*i1*Zc], &c[i1*Zc], Zc*sizeof(unsigned char));
+	memcpy(&c_extension[(2*i1+1)*Zc], &c[i1*Zc], Zc*sizeof(unsigned char));
+      }
+    for (i1=1;i1<simd_size;i1++) {
+      memcpy(&c_extension[(2*ncols*Zc*i1)], &c_extension[i1], (2*ncols*Zc*sizeof(unsigned char))-i1);
+      //    memset(&c_extension[(2*ncols*Zc*i1)],0,i1);
+      /*
+	printf("shift %d: ",i1);
+	for (int j=0;j<64;j++) printf("%d ",c_extension[(2*ncols*Zc*i1)+j]);
+	printf("\n");
+      */
+    }
+    if(impp->tprep != NULL) stop_meas(impp->tprep);
+    //parity check part
+    if(impp->tparity != NULL) start_meas(impp->tparity);
+    encode_parity_check_part_optim(c_extension, d, BG, Zc, Kb);
+    if(impp->tparity != NULL) stop_meas(impp->tparity);
+  }
+  else {
+    if (encode_parity_check_part_orig(c, d, BG, Zc, Kb, block_length)!=0) {
+      printf("Problem with encoder\n");
+      return(-1);
+    }
+  }
+  if(impp->toutput != NULL) start_meas(impp->toutput);
+  // information part and puncture columns
+  /*
+  memcpy(&channel_input[0], &c[2*Zc], (block_length-2*Zc)*sizeof(unsigned char));
+  memcpy(&channel_input[block_length-2*Zc], &d[0], ((nrows-no_punctured_columns) * Zc-removed_bit)*sizeof(unsigned char));
+  */
+#ifdef __AVX2__
+  if ((((2*Zc)&31) == 0) && (((block_length-(2*Zc))&31) == 0)) {
+    //AssertFatal(((2*Zc)&31) == 0,"2*Zc needs to be a multiple of 32 for now\n");
+    //AssertFatal(((block_length-(2*Zc))&31) == 0,"block_length-(2*Zc) needs to be a multiple of 32 for now\n");
+    uint32_t l1 = (block_length-(2*Zc))>>5;
+    uint32_t l2 = ((nrows-no_punctured_columns) * Zc-removed_bit)>>5;
+    __m256i *c256p = (__m256i *)&c[2*Zc];
+    __m256i *d256p = (__m256i *)&d[0];
+    //  if (((block_length-(2*Zc))&31)>0) l1++;
+
+    for (i=0;i<l1;i++)
+      //for (j=0;j<n_segments;j++) ((__m256i *)channel_input[j])[i] = _mm256_and_si256(_mm256_srai_epi16(c256p[i],j),masks[0]);
+    	for (j=macro_segment; j < macro_segment_end; j++) ((__m256i *)channel_input[j])[i] = _mm256_and_si256(_mm256_srai_epi16(c256p[i],j-macro_segment),masks[0]);
+
+
+    //  if ((((nrows-no_punctured_columns) * Zc-removed_bit)&31)>0) l2++;
+
+    for (i1=0;i1<l2;i1++,i++)
+      //for (j=0;j<n_segments;j++) ((__m256i *)channel_input[j])[i] = _mm256_and_si256(_mm256_srai_epi16(d256p[i1],j),masks[0]);
+    	for (j=macro_segment; j < macro_segment_end; j++)  ((__m256i *)channel_input[j])[i] = _mm256_and_si256(_mm256_srai_epi16(d256p[i1],j-macro_segment),masks[0]);
+  }
+  else {
+#ifdef DEBUG_LDPC
+  LOG_W(PHY,"using non-optimized version\n");
+#endif
+    // do non-SIMD version
+    for (i=0;i<(block_length-2*Zc);i++)
+      //for (j=0; j<n_segments; j++)
+      for (j=macro_segment; j < macro_segment_end; j++)
+	channel_input[j][i] = (c[2*Zc+i]>>(j-macro_segment))&1;
+    for (i=0;i<((nrows-no_punctured_columns) * Zc-removed_bit);i++)
+      //for (j=0; j<n_segments; j++)
+    	  for (j=macro_segment; j < macro_segment_end; j++)
+	channel_input[j][block_length-2*Zc+i] = (d[i]>>(j-macro_segment))&1;
+    }
+
+#else
+    AssertFatal(1==0,"Need AVX2 for now\n");
+#endif
+
+  if(impp->toutput != NULL) stop_meas(impp->toutput);
+  return 0;
+}
+