Merge remote-tracking branch 'origin/fix_log2_approx' into integration_2024_w39

openair1/PHY/NR_TRANSPORT/nr_ulsch_demodulation.c

@@ -1684,12 +1684,10 @@ int nr_rx_pusch_tp(PHY_VARS_gNB *gNB,
     for (int aarx = 0; aarx < frame_parms->nb_antennas_rx; aarx++)
       avgs = cmax(avgs, avg[nl * frame_parms->nb_antennas_rx + aarx]);
 
-  pusch_vars->log2_maxh = (log2_approx(avgs) >> 1);
-
   if (rel15_ul->nrOfLayers == 2 && rel15_ul->qam_mod_order >= 6)
     pusch_vars->log2_maxh = (log2_approx(avgs) >> 1) - 3; // for MMSE
-  else if (rel15_ul->nrOfLayers == 1)
-    pusch_vars->log2_maxh = (log2_approx(avgs) >> 1) + 1 + log2_approx(frame_parms->nb_antennas_rx >> 2);
+  else
+    pusch_vars->log2_maxh = (log2_approx(avgs) >> 1) + 1 + log2_approx(frame_parms->nb_antennas_rx >> 1);
 
   if (pusch_vars->log2_maxh < 0)
     pusch_vars->log2_maxh = 0;

openair1/PHY/NR_UE_TRANSPORT/nr_dlsch_demodulation.c

@@ -509,9 +509,9 @@ int nr_rx_pdsch(PHY_VARS_NR_UE *ue,
       int32_t median[MAX_ANT][MAX_ANT];
       for (int aatx = 0; aatx < nl; aatx++)
         for (int aarx = 0; aarx < n_rx; aarx++) {
-          // LOG_I(PHY, "nb_rb %d len %d avg_%d_%d Power per SC is %d\n",nb_rb, len,aarx, aatx,avg[aatx*n_rx+aarx]);
           avgs = cmax(avgs, avg[aatx][aarx]);
-          // LOG_I(PHY, "avgs Power per SC is %d\n", avgs);
+          LOG_D(PHY, "nb_rb %d avg_%d_%d Power per SC is %d\n", nb_rb_pdsch, aarx, aatx, avg[aatx][aarx]);
+          LOG_D(PHY, "avgs Power per SC is %d\n", avgs);
           median[aatx][aarx] = avg[aatx][aarx];
         }
       if (nl > 1) {
@@ -523,7 +523,6 @@ int nr_rx_pdsch(PHY_VARS_NR_UE *ue,
         }
       }
       *log2_maxh = (log2_approx(avgs) / 2) + 1;
-      // LOG_I(PHY, "avgs Power per SC is %d lg2_maxh %d\n", avgs,  log2_maxh);
       LOG_D(PHY, "[DLSCH] AbsSubframe %d.%d log2_maxh = %d (%d)\n", frame % 1024, nr_slot_rx, *log2_maxh, avgs);
     }
     stop_meas_nr_ue_phy(ue, DLSCH_CHANNEL_LEVEL_STATS);
@@ -1099,10 +1098,9 @@ void nr_dlsch_channel_level(uint32_t rx_size_symbol,
   simde__m128i *dl_ch128, avg128D;
   //nb_rb*nre = y * 2^x
   int16_t x = factor2(len);
-  int16_t y = (len)>>x;
-  LOG_D(NR_PHY, "%s: %d = %d * 2^(%d)\n", __func__, len, y, x);
+  int16_t y = (len) >> x;
   uint32_t nb_rb_0 = len / NR_NB_SC_PER_RB + ((len % NR_NB_SC_PER_RB) ? 1 : 0);
-
+  LOG_D(NR_PHY, "nb_rb_0 %d len %d = %d * 2^(%d)\n", nb_rb_0, len, y, x);
   for (int aatx = 0; aatx < n_tx; aatx++) {
     for (int aarx = 0; aarx < n_rx; aarx++) {
       //clear average level
@@ -1118,7 +1116,7 @@ void nr_dlsch_channel_level(uint32_t rx_size_symbol,
       }
       int32_t *tmp = (int32_t *)&avg128D;
       avg[aatx][aarx] = ((int64_t)tmp[0] + tmp[1] + tmp[2] + tmp[3]) / y;
-      //  printf("Channel level : %d\n",avg[(aatx<<1)+aarx]);
+      LOG_D(PHY, "Channel level: %d\n", avg[aatx][aarx]);
     }
   }
 }
@@ -1152,7 +1150,7 @@ static void nr_dlsch_channel_level_median(uint32_t rx_size_symbol,
       }
 
       median[aatx][aarx] = (max + min) >> 1;
-      //printf("Channel level  median [%d]: %d max = %d min = %d\n",aatx*n_rx + aarx, median[aatx*n_rx + aarx],max,min);
+      LOG_D(PHY, "Channel level  median [%d][%d]: %d max = %ld min = %ld\n", aatx, aarx, median[aatx][aarx], max, min);
     }
   }
 }

openair1/PHY/TOOLS/log2_approx.c

@@ -19,58 +19,48 @@
  *      contact@openairinterface.org
  */
 
+#include <simde/x86/avx512/lzcnt.h>
+
 unsigned char log2_approx(unsigned int x)
 {
+  const unsigned int round_val = 3037000499U; // 2^31.5
+  if (!x)
+    return 0;
 
-  int i;
-  unsigned char l2;
-
-  l2=0;
-
-  for (i=0; i<31; i++)
-    if ((x&(1<<i)) != 0)
-      l2 = i+1;
+  int l2 = simde_x_clz32(x);
+  if (x > (round_val >> l2))
+    l2 = 32 - l2;
+  else
+    l2 = 31 - l2;
 
-  //l2 = i;
-
-  //  printf("log2_approx = %d\n",l2);
-  return(l2);
+  return l2;
 }
 
+
 unsigned char factor2(unsigned int x)
 {
-
+  unsigned char l2 = 0;
   int i;
-  unsigned char l2;
-
-  l2=0;
-
-  for (i=0; i<31; i++)
-    if ((x&(1<<i)) != 0)
+  for (i = 0; i < 31; i++)
+    if ((x & (1 << i)) != 0)
       break;
 
   l2 = i;
-
-  //printf("factor2(%d) = %d\n",x,l2);
-  return(l2);
+  return l2;
 }
 
-
-
 unsigned char log2_approx64(unsigned long long int x)
 {
+  const unsigned long long round_val = 13043817825332782212ULL; // 2^63.5
+  if (!x)
+    return 0;
 
-  int i;
-  unsigned char l2;
-
-  l2=0;
-
-  for (i=0; i<63; i++)
-    if ((x&(((long long int) 1)<<i)) != 0)
-      //     l2 = i+1;
-      l2 = i;
+  int l2 = simde_x_clz64(x);
+  if (x > (round_val >> l2))
+    l2 = 64 - l2;
+  else
+    l2 = 63 - l2;
 
-  //  printf("log2_approx = %d\n",l2);
-  return(l2);
+  return l2;
 }
 

openair1/PHY/TOOLS/tests/CMakeLists.txt

@@ -9,3 +9,9 @@ target_link_libraries(benchmark_rotate_vector PRIVATE benchmark::benchmark UTIL
 add_dependencies(tests benchmark_rotate_vector)
 add_test(NAME benchmark_rotate_vector
   COMMAND ./benchmark_rotate_vector)
+
+add_executable(test_log2_approx test_log2_approx.cpp ../log2_approx.c)
+target_link_libraries(test_log2_approx PRIVATE GTest::gtest LOG minimal_lib)
+add_dependencies(tests test_log2_approx)
+add_test(NAME test_log2_approx
+  COMMAND ./test_log2_approx)

openair1/PHY/TOOLS/tests/test_log2_approx.cpp

+#include <gtest/gtest.h>
+extern "C" {
+#include "openair1/PHY/TOOLS/tools_defs.h"
+#include "common/utils/LOG/log.h"
+}
+#include <cmath>
+
+uint8_t log2_approx_ref(uint32_t x)
+{
+  return std::round(std::log2(x));
+}
+
+uint8_t log2_approx64_ref(unsigned long long int x)
+{
+  return std::round(std::log2(static_cast<long double>(x)));
+}
+
+TEST(log2_approx, complete)
+{
+  for (uint32_t i = 0; i < UINT32_MAX; i++)
+    EXPECT_EQ(log2_approx(i), log2_approx_ref(i));
+}
+
+TEST(log2_approx64, boundaries)
+{
+  for (long double i = 0; i < 64; i++) {
+    unsigned long long i2 = std::pow(2.0L, i + 0.5L);
+    for (unsigned long long j = -10; j <= 10; j++) {
+      unsigned long long x = i2 + j;
+      EXPECT_EQ(log2_approx64(x), log2_approx64_ref(x));
+    }
+  }
+}
+
+int main(int argc, char **argv)
+{
+  logInit();
+  testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}

openair1/PHY/nr_phy_common/src/nr_phy_common.c

@@ -46,8 +46,8 @@ void nr_qpsk_llr(int32_t *rxdataF_comp, int16_t *llr, uint32_t nb_re)
   c16_t *rxF   = (c16_t *)rxdataF_comp;
   c16_t *llr32 = (c16_t *)llr;
   for (int i = 0; i < nb_re; i++) {
-    llr32[i].r = rxF[i].r >> 3;
-    llr32[i].i = rxF[i].i >> 3;
+    llr32[i].r = rxF[i].r >> 4;
+    llr32[i].i = rxF[i].i >> 4;
   }
 }