new luts for LDPC decoder to reduce decoding latency.

openair1/PHY/CODING/TESTBENCH/ldpctest.c

@@ -170,6 +170,7 @@ int test_ldpc(short No_iteration,
   *errors_bit_uncoded=0;
   *crc_misses=0;
 
+
   // generate input block
   for(j=0;j<MAX_NUM_DLSCH_SEGMENTS;j++) {
     test_input[j]=(unsigned char *)malloc16(sizeof(unsigned char) * block_length/8);
@@ -663,6 +664,8 @@ int main(int argc, char *argv[])
 
   fprintf(fd,"SNR BLER BER UNCODED_BER ENCODER_MEAN ENCODER_STD ENCODER_MAX DECODER_TIME_MEAN DECODER_TIME_STD DECODER_TIME_MAX DECODER_ITER_MEAN DECODER_ITER_STD DECODER_ITER_MAX\n");
 
+  nrLDPC_prep();
+
   for (SNR=SNR0;SNR<SNR0+20.0;SNR+=SNR_step)
   {
 	  //reset_meas(&time_optim);

openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_cnProc.h

@@ -87,23 +87,29 @@ static inline void nrLDPC_cnProc_BG2(t_nrLDPC_lut* p_lut, t_nrLDPC_procBuf* p_pr
             // Set of results pointer to correct BN address
             p_cnProcBufResBit = p_cnProcBufRes + (j*bitOffsetInGroup);
 
+            __m256i *pj0 = &p_cnProcBuf[lut_idxCnProcG3[j][0]];
+            __m256i *pj1 = &p_cnProcBuf[lut_idxCnProcG3[j][1]];
+
             // Loop over CNs
             for (i=0; i<M; i++)
             {
                 // Abs and sign of 32 CNs (first BN)
-                ymm0 = p_cnProcBuf[lut_idxCnProcG3[j][0] + i];
+	      //                ymm0 = p_cnProcBuf[lut_idxCnProcG3[j][0] + i];
+	        ymm0 = pj0[i];
                 sgn  = _mm256_sign_epi8(*p_ones, ymm0);
                 min  = _mm256_abs_epi8(ymm0);
 
                 // 32 CNs of second BN
-                ymm0 = p_cnProcBuf[lut_idxCnProcG3[j][1] + i];
+		//  ymm0 = p_cnProcBuf[lut_idxCnProcG3[j][1] + i];
+		ymm0 = pj1[i];
                 min  = _mm256_min_epu8(min, _mm256_abs_epi8(ymm0));
                 sgn  = _mm256_sign_epi8(sgn, ymm0);
 
                 // Store result
                 min = _mm256_min_epu8(min, *p_maxLLR); // 128 in epi8 is -127
-                *p_cnProcBufResBit = _mm256_sign_epi8(min, sgn);
-                p_cnProcBufResBit++;
+                //*p_cnProcBufResBit = _mm256_sign_epi8(min, sgn);
+                //p_cnProcBufResBit++;
+		p_cnProcBufResBit[i]=_mm256_sign_epi8(min, sgn);
             }
         }
     }

openair1/PHY/CODING/nrLDPC_decoder/nrLDPC_types.h

@@ -48,7 +48,9 @@ typedef struct nrLDPC_lut {
     const uint32_t* llr2CnProcBuf; /**< LUT for input LLRs to CN processing buffer */
     const uint8_t*  numEdgesPerBn; /**< LUT with number of edges per BN */
     const uint32_t* cn2bnProcBuf; /**< LUT for transferring CN processing results to BN processing buffer */
-    const uint16_t* llr2llrProcBuf; /**< LUT for transferring input LLRs to LLR processing buffer */
+    const uint32_t* cn2bnProcBuf2; /**< LUT for transferring CN processing results to BN processing buffer */
+  uint32_t cn2bnProcBuf2_size;
+  const uint16_t* llr2llrProcBuf; /**< LUT for transferring input LLRs to LLR processing buffer */
 } t_nrLDPC_lut;
 
 /**