optimized polar encoder/decoder functions for PBCH and 41-bit DCI

openair1/PHY/CODING/TESTBENCH/polartest.c

@@ -98,8 +98,8 @@ int main(int argc, char *argv[]) {
 		aggregation_level = NR_POLAR_PBCH_AGGREGATION_LEVEL;
 	} else if (polarMessageType == 1) { //DCI
 		//testLength = nr_get_dci_size(params_rel15->dci_format, params_rel15->rnti_type, &fp->initial_bwp_dl, cfg);
-	  testLength = 64; //20;
-		coderLength = 108; //to be changed by aggregate level function.
+	  testLength = 41; //20;
+	  coderLength = 108*8; //to be changed by aggregate level function.
 	} else if (polarMessageType == -1) { //UCI
 		//testLength = ;
 		//coderLength = ;
@@ -325,8 +325,8 @@ int main(int argc, char *argv[]) {
 				printf("%d\n",(testInput[0]>>i)&1);*/
 
 
-
-
+			int len_mod64=currentPtr->payloadBits&63;
+			((uint64_t*)testInput)[currentPtr->payloadBits/64]&=((((uint64_t)1)<<len_mod64)-1);
 
 			start_meas(&timeEncoder);
 			if (decoder_int16==0)
@@ -391,7 +391,7 @@ int main(int argc, char *argv[]) {
 			} else {
 			  for (int j = 0; j < currentPtr->payloadBits; j++) {
 			    if (((estimatedOutput[0]>>j) & 1) != ((testInput[0]>>j) & 1)) nBitError++;
-			    
+			    //			    printf("bit %d: %d => %d\n",j,(testInput[0]>>j)&1,(estimatedOutput[0]>>j)&1);
 			  }
 			
 
@@ -424,7 +424,8 @@ int main(int argc, char *argv[]) {
 		printf("[ListSize=%d, Appr=%d] SNR=%+8.3f, BLER=%9.6f, BER=%12.9f, t_Encoder=%9.3fus, t_Decoder=%9.3fus\n",
 				decoderListSize, pathMetricAppr, SNR, ((double)blockErrorCumulative/iterations),
 				((double)bitErrorCumulative / (iterations*testLength)),
-				(timeEncoderCumulative/iterations),timeDecoderCumulative/iterations);
+		       (double)timeEncoder.diff/timeEncoder.trials/(cpu_freq_GHz*1000.0),(double)timeDecoder.diff/timeDecoder.trials/(cpu_freq_GHz*1000.0));
+		       //(timeEncoderCumulative/iterations),timeDecoderCumulative/iterations);
 
 		if (blockErrorCumulative==0 && bitErrorCumulative==0)
 		  break;

openair1/PHY/CODING/crc_byte.c

@@ -168,14 +168,12 @@ unsigned int crc24c (unsigned char * inptr,
   resbit = (bitlen % 8);
 
   while (octetlen-- > 0) {
-/*#ifdef DEBUG_CRC24C
-	  printf("crc24c: in %x => crc %x (%x)\n",crc,*inptr,crc24cTable[(*inptr) ^ (crc >> 24)]);
-#endif*/
     crc = (crc << 8) ^ crc24cTable[(*inptr++) ^ (crc >> 24)];
   }
 
-  if (resbit > 0)
+  if (resbit > 0) {
     crc = (crc << resbit) ^ crc24cTable[((*inptr) >> (8 - resbit)) ^ (crc >> (32 - resbit))];
+  }
 
   return crc;
 }

openair1/PHY/CODING/nrPolar_tools/nr_polar_decoder.c

@@ -1055,6 +1055,9 @@ void init_polar_deinterleaver_table(t_nrPolar_params *polarParams) {
     else numbits=residue;
     for (int i=0;i<numbits;i++) {
       ip=polarParams->interleaving_pattern[(8*byte)+i];
+#if 1
+      printf("byte %d, i %d => ip %d\n",byte,i,ip);
+#endif
       ipmod64 = ip&63;
       AssertFatal(ip<128,"ip = %d\n",ip);
       for (int val=0;val<256;val++) {
@@ -1102,8 +1105,10 @@ int8_t polar_decoder_int16(int16_t *input,
       polarParams->B_tab0[6][Cprimebyte[6]] |
       polarParams->B_tab0[7][Cprimebyte[7]];
   }
-  if (polarParams->K<129) {
-    for (int k=0;k<polarParams->K;k++) {
+  else if (polarParams->K<129) {
+    int len = polarParams->K/8;
+    if ((polarParams->K&7) > 0) len++;
+    for (int k=0;k<len;k++) {
       B[0] |= polarParams->B_tab0[k][Cprimebyte[k]];
       B[1] |= polarParams->B_tab1[k][Cprimebyte[k]];
     }
@@ -1116,18 +1121,23 @@ int8_t polar_decoder_int16(int16_t *input,
   int crclen = polarParams->crcParityBits;
   int quadwpos2  = polarParams->K>>6;
   uint64_t rxcrc;
+  uint32_t crc;
   if (len_mod64==0) rxcrc = 0;
   else              rxcrc = B[quadwpos]>>len_mod64;
 
   if (quadwpos2>quadwpos) { // there are extra CRC bits in the next quadword
     rxcrc |= (B[quadwpos2]<<(64-len_mod64));
   }
+  // clear everything but payload bits in last quadword
+  B[quadwpos]&=((((uint64_t)1)<<len_mod64)-1);
+  crc = crc24c((uint8_t*)B,polarParams->payloadBits)>>8;
 #if 0
-  printf("Decoded B %llx%llx (crc %x,B>>payloadBits %x)\n",B[1],B[0],crc24c((uint8_t*)&B,polarParams->payloadBits)>>8,
-   	 (uint32_t)rxcrc);
+  printf("A %llx B %llx|%llx Cprime %llx|%llx  (crc %x,rxcrc %llx %d)\n",
+	 B[quadwpos]&((((uint64_t)1)<<len_mod64)-1),
+	 B[1],B[0],Cprime[1],Cprime[0],crc,
+   	 rxcrc,polarParams->payloadBits);
 #endif
-  if ((uint64_t)(crc24c((uint8_t*)&B[0],polarParams->payloadBits)>>8) == rxcrc) {
-  
+  if (((uint64_t)crc) == rxcrc) {
     int k=0;
     // copy quadwords without CRC directly
     for (k=0;k<polarParams->payloadBits/64;k++) out[k]=B[k];

openair1/PHY/CODING/nrPolar_tools/nr_polar_decoding_tools.c

@@ -34,7 +34,7 @@
 #include "PHY/sse_intrin.h"
 #include "PHY/impl_defs_top.h"
 
-//#define DEBUG_NEW_IMPL
+//#define DEBUG_NEW_IMPL 1
 
 void updateLLR(double ***llr,
 	       uint8_t **llrU,
@@ -233,7 +233,7 @@ decoder_node_t *add_nodes(int level,int first_leaf_index,t_nrPolar_params *pp) {
   for (int i=0;i<Nv;i++) {
     if (pp->information_bit_pattern[i+first_leaf_index]>0) all_frozen_below=0; 
   }
-if (all_frozen_below==0) new_node->left=add_nodes(level-1,first_leaf_index,pp);
+  if (all_frozen_below==0) new_node->left=add_nodes(level-1,first_leaf_index,pp);
   else {
 #ifdef DEBUG_NEW_IMPL
     printf("aggregating frozen bits %d ... %d at level %d (%s)\n",first_leaf_index,first_leaf_index+Nv-1,level,((first_leaf_index/Nv)&1)==0?"left":"right");
@@ -243,6 +243,9 @@ if (all_frozen_below==0) new_node->left=add_nodes(level-1,first_leaf_index,pp);
   }
   if (all_frozen_below==0) new_node->right=add_nodes(level-1,first_leaf_index+(Nv/2),pp);
 
+#ifdef DEBUG_NEW_IMPL
+  printf("new_node (%d): first_leaf_index %d, left %p, right %p\n",Nv,first_leaf_index,new_node->left,new_node->right);
+#endif  
   return(new_node);
 }
 
@@ -251,7 +254,9 @@ void build_decoder_tree(t_nrPolar_params *pp) {
 
   pp->tree.num_nodes=0;
   pp->tree.root = add_nodes(pp->n,0,pp);
-  			       
+#ifdef DEBUG_NEW_IMPL
+  printf("root : left %p, right %p\n",pp->tree.root->left,pp->tree.root->right);
+#endif
 }
 
 #if defined(__arm__) || defined(__aarch64__)

openair1/PHY/CODING/nrPolar_tools/nr_polar_defs.h

@@ -113,10 +113,10 @@ struct nrPolar_params {
   uint64_t **G_N_tab;
   int groupsize;
   int     *rm_tab;
-  uint64_t cprime_tab0[8][256];
-  uint64_t cprime_tab1[8][256];
-  uint64_t B_tab0[8][256];
-  uint64_t B_tab1[8][256];
+  uint64_t cprime_tab0[32][256];
+  uint64_t cprime_tab1[32][256];
+  uint64_t B_tab0[32][256];
+  uint64_t B_tab1[32][256];
   uint32_t* crc256Table;
   uint8_t **extended_crc_generator_matrix;
   //lowercase: bits, Uppercase: Bits stored in bytes

openair1/PHY/CODING/nrPolar_tools/nr_polar_encoder.c

@@ -365,7 +365,9 @@ static inline void polar_rate_matching(t_nrPolar_paramsPtr polarParams,void *in,
   if (polarParams->groupsize == 8) 
     for (int i=0;i<polarParams->encoderLength>>3;i++) ((uint8_t*)out)[i] = ((uint8_t *)in)[polarParams->rm_tab[i]];
   else
-    for (int i=0;i<polarParams->encoderLength>>4;i++) ((uint16_t*)out)[i] = ((uint16_t *)in)[polarParams->rm_tab[i]];
+    for (int i=0;i<polarParams->encoderLength>>4;i++) {
+      ((uint16_t*)out)[i] = ((uint16_t *)in)[polarParams->rm_tab[i]];
+    }
 }
 
 void build_polar_tables(t_nrPolar_paramsPtr polarParams) {
@@ -390,6 +392,7 @@ void build_polar_tables(t_nrPolar_paramsPtr polarParams) {
       polarParams->cprime_tab1[byte][val] = 0;
       for (int i=0;i<numbits;i++) {
 	ip=polarParams->deinterleaving_pattern[(8*byte)+i];
+	if (val==0) printf("%d => %d\n",(8*byte)+i,ip);
 	AssertFatal(ip<128,"ip = %d\n",ip);
 	bit_i=(val>>i)&1;
 	if (ip<64) polarParams->cprime_tab0[byte][val] |= (((uint64_t)bit_i)<<ip);				
@@ -461,7 +464,7 @@ void polar_encoder_fast(int64_t *A,
 			t_nrPolar_paramsPtr polarParams) {
 
   AssertFatal(polarParams->K > 32, "K = %d < 33, is not supported yet\n",polarParams->K);
-  AssertFatal(polarParams->K < 65, "K = %d > 64, is not supported yet\n",polarParams->K);
+  AssertFatal(polarParams->K < 129, "K = %d > 64, is not supported yet\n",polarParams->K);
 
   uint64_t B[4]={0,0,0,0},Cprime[4]={0,0,0,0};
   int bitlen = polarParams->payloadBits;
@@ -472,16 +475,20 @@ void polar_encoder_fast(int64_t *A,
   AssertFatal(polarParams->crcParityBits == 24,"support for 24-bit crc only for now\n");
 
   int bitlen0=bitlen;
-  for (int i=0;i<(1+(bitlen>>6));i++)
-    if (bitlen0<64)
-      B[i] = ((A[i])&((((uint64_t)1)<<bitlen0)-1)) |((uint64_t)((crcmask^(crc24c((uint8_t*)A,bitlen0)>>8)))<<bitlen0);
+
+  uint64_t tcrc = (uint64_t)((crcmask^(crc24c((uint8_t*)A,bitlen)>>8)));
+  int n;
+  for (n=0;n<(1+(bitlen>>6));n++)
+    if (bitlen0<64) B[n] = ((A[n])&((((uint64_t)1)<<bitlen0)-1)) | (tcrc<<bitlen0);
     else {
-      B[i] = A[i];
+      B[n] = A[n];
       bitlen0-=64;
     }
+  // handle residual part of CRC in next quadword
+  if (polarParams->crcParityBits > (64-bitlen0)) B[n] = tcrc>>(64-bitlen0);
   uint8_t *Bbyte = (uint8_t*)B;
   // for each byte of B, lookup in corresponding table for 64-bit word corresponding to that byte and its position
-  if (bitlen<65) 
+  if (polarParams->K<65) 
     Cprime[0] = polarParams->cprime_tab0[0][Bbyte[0]] |
                 polarParams->cprime_tab0[1][Bbyte[1]] |
                 polarParams->cprime_tab0[2][Bbyte[2]] |
@@ -491,30 +498,37 @@ void polar_encoder_fast(int64_t *A,
                 polarParams->cprime_tab0[6][Bbyte[6]] |
                 polarParams->cprime_tab0[7][Bbyte[7]];
   
-  else if (bitlen < 129) {
-    Cprime[0] = polarParams->cprime_tab0[0][Bbyte[0]] |
-                polarParams->cprime_tab0[1][Bbyte[1]] |
-                polarParams->cprime_tab0[2][Bbyte[2]] |
-                polarParams->cprime_tab0[3][Bbyte[3]] |
-                polarParams->cprime_tab0[4][Bbyte[4]] |
-                polarParams->cprime_tab0[5][Bbyte[5]] |
-                polarParams->cprime_tab0[6][Bbyte[6]] |
-                polarParams->cprime_tab0[7][Bbyte[7]];
-    Cprime[1] = polarParams->cprime_tab1[0][Bbyte[0]] |
-                polarParams->cprime_tab1[1][Bbyte[1]] |
-                polarParams->cprime_tab1[2][Bbyte[2]] |
-                polarParams->cprime_tab1[3][Bbyte[3]] |
-                polarParams->cprime_tab1[4][Bbyte[4]] |
-                polarParams->cprime_tab1[5][Bbyte[5]] |
-                polarParams->cprime_tab1[6][Bbyte[6]] |
-                polarParams->cprime_tab1[7][Bbyte[7]];
+  else if (polarParams->K < 129) {
+    for (int i=0;i<1+(polarParams->K/8);i++) {
+      Cprime[0] |= polarParams->cprime_tab0[i][Bbyte[i]];
+      Cprime[1] |= polarParams->cprime_tab1[i][Bbyte[i]];
+    }
   }
 
 #ifdef DEBUG_POLAR_ENCODER
+  if (polarParams->K<65) 
     printf("A %llx B %llx Cprime %llx (payload bits %d,crc %x)\n",
-	 (unsigned long long)((A[0])&((((uint64_t)1)<<bitlen)-1)),
-	 (unsigned long long)B[0],(unsigned long long)Cprime[0],polarParams->payloadBits,
-	 crc24c((uint8_t*)A,bitlen));
+	   (unsigned long long)(A[0]&(((uint64_t)1<<bitlen)-1)),
+	   (unsigned long long)(B[0]),
+	   (unsigned long long)(Cprime[0]),
+	   polarParams->payloadBits,
+	   tcrc);
+  else if (polarParams->K<129) {
+    if (bitlen<64)
+      printf("A %llx B %llx|%llx Cprime %llx|%llx (payload bits %d,crc %x)\n",
+	     (unsigned long long)(A[0]&(((uint64_t)1<<bitlen)-1)),
+	     (unsigned long long)(B[1]),(unsigned long long)(B[0]),
+	     (unsigned long long)(Cprime[1]),(unsigned long long)(Cprime[0]),
+	     polarParams->payloadBits,
+	     tcrc);
+    else 
+      printf("A %llx|%llx B %llx|%llx Cprime %llx|%llx (payload bits %d,crc %x)\n",
+	     (unsigned long long)(A[1]&(((uint64_t)1<<(bitlen-64))-1)),(unsigned long long)(A[0]),
+	     (unsigned long long)(B[1]),(unsigned long long)(B[0]),
+	     (unsigned long long)(Cprime[1]),(unsigned long long)(Cprime[0]),
+	     polarParams->payloadBits,
+	     crc24c((uint8_t*)A,bitlen)>>8);
+  }
 #endif
   /*  printf("Bbytes : %x.%x.%x.%x.%x.%x.%x.%x\n",Bbyte[0],Bbyte[1],Bbyte[2],Bbyte[3],Bbyte[4],Bbyte[5],Bbyte[6],Bbyte[7]);
   printf("%llx,%llx,%llx,%llx,%llx,%llx,%llx,%llx\n",polarParams->cprime_tab[0][Bbyte[0]] , 
@@ -548,25 +562,25 @@ void polar_encoder_fast(int64_t *A,
       Cprime_i = -((Cprime[j]>>i)&1); // this converts bit 0 as, 0 => 0000x00, 1 => 1111x11
 #ifdef DEBUG_POLAR_ENCODER
       printf("%llx Cprime_%d (%llx) G %llx,%llx,%llx,%llx,%llx,%llx,%llx,%llx\n",
-	     Cprime_i,i,(Cprime[j]>>i) &1,
-	     polarParams->G_N_tab[i][0],
-	     polarParams->G_N_tab[i][1],
-	     polarParams->G_N_tab[i][2],
-	     polarParams->G_N_tab[i][3],
-	     polarParams->G_N_tab[i][4],
-	     polarParams->G_N_tab[i][5],
-	     polarParams->G_N_tab[i][6],
-	     polarParams->G_N_tab[i][7]);
+	     Cprime_i,off+i,(Cprime[j]>>i) &1,
+	     polarParams->G_N_tab[off+i][0],
+	     polarParams->G_N_tab[off+i][1],
+	     polarParams->G_N_tab[off+i][2],
+	     polarParams->G_N_tab[off+i][3],
+	     polarParams->G_N_tab[off+i][4],
+	     polarParams->G_N_tab[off+i][5],
+	     polarParams->G_N_tab[off+i][6],
+	     polarParams->G_N_tab[off+i][7]);
 #endif
-      
-      D[0] ^= (Cprime_i & polarParams->G_N_tab[i][0]);
-      D[1] ^= (Cprime_i & polarParams->G_N_tab[i][1]);
-      D[2] ^= (Cprime_i & polarParams->G_N_tab[i][2]);
-      D[3] ^= (Cprime_i & polarParams->G_N_tab[i][3]);
-      D[4] ^= (Cprime_i & polarParams->G_N_tab[i][4]);
-      D[5] ^= (Cprime_i & polarParams->G_N_tab[i][5]);
-      D[6] ^= (Cprime_i & polarParams->G_N_tab[i][6]);
-      D[7] ^= (Cprime_i & polarParams->G_N_tab[i][7]);
+      uint64_t *Gi=polarParams->G_N_tab[off+i];
+      D[0] ^= (Cprime_i & Gi[0]);
+      D[1] ^= (Cprime_i & Gi[1]);
+      D[2] ^= (Cprime_i & Gi[2]);
+      D[3] ^= (Cprime_i & Gi[3]);
+      D[4] ^= (Cprime_i & Gi[4]);
+      D[5] ^= (Cprime_i & Gi[5]);
+      D[6] ^= (Cprime_i & Gi[6]);
+      D[7] ^= (Cprime_i & Gi[7]);
     }
   }
 #ifdef DEBUG_POLAR_ENCODER