Filter_ACRMS: make reference implementation properly avoid divide-by-zero, updated to latest scopehal with bug fixes for ACRMS

Author: azonenberg

lib

@@ -134,10 +134,18 @@ TEST_CASE("Filter_ACRMS")
 		REQUIRE(fabs(cpurms - gpurms) < epsilon3);
 
 		//Verify the cycle-by-cycle results
-		//TODO: why do we occasionally get spikes of larger deltas? smaller epsilon should be achievable
-		const float epsilon2 = 0.025;
+		const float epsilon2 = 0.03;
 		SparseAnalogWaveform& gpucycles = *dynamic_cast<SparseAnalogWaveform*>(filter->GetData(0));
 		gpucycles.PrepareForCpuAccess();
+		if(cycles.size() != gpucycles.size())
+		{
+			LogWarning("size mismatch, CPU found %zu edges, GPU found %zu\n", cycles.size(), gpucycles.size());
+			size_t nlast = cycles.size() - 1;
+			LogNotice("last CPU times: %" PRIi64 ", %" PRIi64 "\n", cycles.m_offsets[nlast], cycles.m_offsets[nlast-1]);
+
+			nlast = gpucycles.size() - 1;
+			LogNotice("last GPU times: %" PRIi64 ", %" PRIi64 "\n", gpucycles.m_offsets[nlast], gpucycles.m_offsets[nlast-1]);
+		}
 		REQUIRE(cycles.size() == gpucycles.size());
 		for(size_t i=0; i<gpucycles.size(); i++)
 		{
@@ -213,19 +221,21 @@ float ReferenceImplementation(UniformAnalogWaveform* wfm, SparseAnalogWaveform&
 		//on which AC RMS calculation was performed
 		int64_t delta = j - start - 1;
 
-		if (delta != 0)
+		if (delta == 0)
+			temp = 0;
+		else
 		{
 			//Divide by total number of samples for one cycle
 			temp /= delta;
 
 			//Take square root to get the final AC RMS Value of one cycle
 			temp = sqrt(temp);
-
-			//Push values to the waveform
-			cycles.m_offsets.push_back(start);
-			cycles.m_durations.push_back(delta);
-			cycles.m_samples.push_back(temp);
 		}
+
+		//Push values to the waveform
+		cycles.m_offsets.push_back(start);
+		cycles.m_durations.push_back(delta);
+		cycles.m_samples.push_back(temp);
 	}
 
 	return rms;