Fix signal_energy_nodc for lengths that are not multiples of 4

openair1/PHY/TOOLS/tests/CMakeLists.txt

@@ -0,0 +1,5 @@
+add_executable(test_signal_energy test_signal_energy.cpp ../signal_energy.c)
+target_link_libraries(test_signal_energy PRIVATE GTest::gtest UTIL)
+add_dependencies(tests test_signal_energy)
+add_test(NAME test_signal_energy
+  COMMAND ./test_signal_energy)

openair1/PHY/TOOLS/tests/test_signal_energy.cpp

@@ -0,0 +1,31 @@
+#include <gtest/gtest.h>
+extern "C" {
+#include "openair1/PHY/TOOLS/tools_defs.h"
+extern int32_t signal_energy_nodc(const c16_t *input, uint32_t length);
+}
+#include <vector>
+#include <algorithm>
+
+int32_t signal_energy_nodc_ref(const c16_t *input, uint32_t length)
+{
+  float sum = 0;
+  for (auto i = 0U; i < length; i++) {
+    sum += input[i].r * input[i].r + input[i].i * input[i].i;
+  }
+  return sum / length;
+}
+
+TEST(signal_energy_nodc, size_6)
+{
+  std::vector<c16_t> input;
+  input.resize(6);
+  std::fill(input.begin(), input.end(), (c16_t){42, 42});
+  EXPECT_EQ(signal_energy_nodc(input.data(), input.size()),
+            signal_energy_nodc_ref(input.data(), input.size()));
+}
+
+int main(int argc, char **argv)
+{
+  testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}