[yul-phaser] Add FitnessMetricCombination and derived classes for average, sum, min and max

test/yulPhaser/FitnessMetrics.cpp

@@ -78,6 +78,21 @@ protected:
 	Program m_optimisedProgram = optimisedProgram(m_program);
 };
 
+class FitnessMetricCombinationFixture: public ProgramBasedMetricFixture
+{
+protected:
+	vector<shared_ptr<FitnessMetric>> m_simpleMetrics = {
+		make_shared<ProgramSize>(m_program, 1),
+		make_shared<ProgramSize>(m_program, 2),
+		make_shared<ProgramSize>(m_program, 3),
+	};
+	vector<size_t> m_fitness = {
+		m_simpleMetrics[0]->evaluate(m_chromosome),
+		m_simpleMetrics[1]->evaluate(m_chromosome),
+		m_simpleMetrics[2]->evaluate(m_chromosome),
+	};
+};
+
 BOOST_AUTO_TEST_SUITE(Phaser)
 BOOST_AUTO_TEST_SUITE(FitnessMetricsTest)
 BOOST_AUTO_TEST_SUITE(ProgramBasedMetricTest)
@@ -173,6 +188,45 @@ BOOST_FIXTURE_TEST_CASE(evaluate_should_multiply_the_result_by_scaling_factor, P
 	BOOST_TEST(RelativeProgramSize(m_program, 4).evaluate(m_chromosome) == round(10000.0 * sizeRatio));
 }
 
+BOOST_AUTO_TEST_SUITE_END()
+BOOST_AUTO_TEST_SUITE(FitnessMetricCombinationTest)
+
+BOOST_FIXTURE_TEST_CASE(FitnessMetricAverage_evaluate_should_compute_average_of_values_returned_by_metrics_passed_to_it, FitnessMetricCombinationFixture)
+{
+	FitnessMetricAverage metric(m_simpleMetrics);
+
+	assert(m_simpleMetrics.size() == 3);
+	BOOST_TEST(metric.evaluate(m_chromosome) == (m_fitness[0] + m_fitness[1] + m_fitness[2]) / 3);
+	BOOST_TEST(metric.metrics() == m_simpleMetrics);
+}
+
+BOOST_FIXTURE_TEST_CASE(FitnessMetricSum_evaluate_should_compute_sum_of_values_returned_by_metrics_passed_to_it, FitnessMetricCombinationFixture)
+{
+	FitnessMetricSum metric(m_simpleMetrics);
+
+	assert(m_simpleMetrics.size() == 3);
+	BOOST_TEST(metric.evaluate(m_chromosome) == m_fitness[0] + m_fitness[1] + m_fitness[2]);
+	BOOST_TEST(metric.metrics() == m_simpleMetrics);
+}
+
+BOOST_FIXTURE_TEST_CASE(FitnessMetricMaximum_evaluate_should_compute_maximum_of_values_returned_by_metrics_passed_to_it, FitnessMetricCombinationFixture)
+{
+	FitnessMetricMaximum metric(m_simpleMetrics);
+
+	assert(m_simpleMetrics.size() == 3);
+	BOOST_TEST(metric.evaluate(m_chromosome) == max(m_fitness[0], max(m_fitness[1], m_fitness[2])));
+	BOOST_TEST(metric.metrics() == m_simpleMetrics);
+}
+
+BOOST_FIXTURE_TEST_CASE(FitnessMetricMinimum_evaluate_should_compute_minimum_of_values_returned_by_metrics_passed_to_it, FitnessMetricCombinationFixture)
+{
+	FitnessMetricMinimum metric(m_simpleMetrics);
+
+	assert(m_simpleMetrics.size() == 3);
+	BOOST_TEST(metric.evaluate(m_chromosome) == min(m_fitness[0], min(m_fitness[1], m_fitness[2])));
+	BOOST_TEST(metric.metrics() == m_simpleMetrics);
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 BOOST_AUTO_TEST_SUITE_END()
 BOOST_AUTO_TEST_SUITE_END()

tools/yulPhaser/FitnessMetrics.cpp

@@ -50,3 +50,47 @@ size_t RelativeProgramSize::evaluate(Chromosome const& _chromosome)
 		static_cast<double>(optimisedSize) / unoptimisedSize * scalingFactor
 	));
 }
+
+size_t FitnessMetricAverage::evaluate(Chromosome const& _chromosome)
+{
+	assert(m_metrics.size() > 0);
+
+	size_t total = m_metrics[0]->evaluate(_chromosome);
+	for (size_t i = 1; i < m_metrics.size(); ++i)
+		total += m_metrics[i]->evaluate(_chromosome);
+
+	return total / m_metrics.size();
+}
+
+size_t FitnessMetricSum::evaluate(Chromosome const& _chromosome)
+{
+	assert(m_metrics.size() > 0);
+
+	size_t total = m_metrics[0]->evaluate(_chromosome);
+	for (size_t i = 1; i < m_metrics.size(); ++i)
+		total += m_metrics[i]->evaluate(_chromosome);
+
+	return total;
+}
+
+size_t FitnessMetricMaximum::evaluate(Chromosome const& _chromosome)
+{
+	assert(m_metrics.size() > 0);
+
+	size_t maximum = m_metrics[0]->evaluate(_chromosome);
+	for (size_t i = 1; i < m_metrics.size(); ++i)
+		maximum = max(maximum, m_metrics[i]->evaluate(_chromosome));
+
+	return maximum;
+}
+
+size_t FitnessMetricMinimum::evaluate(Chromosome const& _chromosome)
+{
+	assert(m_metrics.size() > 0);
+
+	size_t minimum = m_metrics[0]->evaluate(_chromosome);
+	for (size_t i = 1; i < m_metrics.size(); ++i)
+		minimum = min(minimum, m_metrics[i]->evaluate(_chromosome));
+
+	return minimum;
+}

tools/yulPhaser/FitnessMetrics.h

@@ -113,4 +113,60 @@ private:
 	size_t m_fixedPointPrecision;
 };
 
+/**
+ * Abstract base class for fitness metrics that compute their value based on values of multiple
+ * other, nested metrics.
+ */
+class FitnessMetricCombination: public FitnessMetric
+{
+public:
+	explicit FitnessMetricCombination(std::vector<std::shared_ptr<FitnessMetric>> _metrics):
+		m_metrics(std::move(_metrics)) {}
+
+	std::vector<std::shared_ptr<FitnessMetric>> const& metrics() const { return m_metrics; }
+
+protected:
+	std::vector<std::shared_ptr<FitnessMetric>> m_metrics;
+};
+
+/**
+ * Fitness metric that returns the average of values of its nested metrics.
+ */
+class FitnessMetricAverage: public FitnessMetricCombination
+{
+public:
+	using FitnessMetricCombination::FitnessMetricCombination;
+	size_t evaluate(Chromosome const& _chromosome) override;
+};
+
+/**
+ * Fitness metric that returns the sum of values of its nested metrics.
+ */
+class FitnessMetricSum: public FitnessMetricCombination
+{
+public:
+	using FitnessMetricCombination::FitnessMetricCombination;
+	size_t evaluate(Chromosome const& _chromosome) override;
+};
+
+/**
+ * Fitness metric that returns the highest of values of its nested metrics.
+ */
+class FitnessMetricMaximum: public FitnessMetricCombination
+{
+public:
+	using FitnessMetricCombination::FitnessMetricCombination;
+	size_t evaluate(Chromosome const& _chromosome) override;
+};
+
+/**
+ * Fitness metric that returns the lowest of values of its nested metrics.
+ */
+class FitnessMetricMinimum: public FitnessMetricCombination
+{
+public:
+	using FitnessMetricCombination::FitnessMetricCombination;
+	size_t evaluate(Chromosome const& _chromosome) override;
+};
+
 }