[yul-phaser] Add ProgramSize metric

test/CMakeLists.txt

@@ -143,6 +143,7 @@ set(yul_phaser_sources
     yulPhaser/Common.cpp
     yulPhaser/CommonTest.cpp
     yulPhaser/Chromosome.cpp
+    yulPhaser/FitnessMetrics.cpp
     yulPhaser/Population.cpp
     yulPhaser/Program.cpp
     yulPhaser/SimulationRNG.cpp

test/yulPhaser/FitnessMetrics.cpp

@@ -0,0 +1,80 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <tools/yulPhaser/FitnessMetrics.h>
+
+#include <libyul/optimiser/EquivalentFunctionCombiner.h>
+#include <libyul/optimiser/UnusedPruner.h>
+
+#include <liblangutil/CharStream.h>
+
+#include <boost/test/unit_test.hpp>
+
+using namespace std;
+using namespace solidity::langutil;
+using namespace solidity::yul;
+
+namespace solidity::phaser::test
+{
+
+class FitnessMetricFixture
+{
+protected:
+	FitnessMetricFixture():
+		m_sourceStream(SampleSourceCode, ""),
+		m_program(Program::load(m_sourceStream)) {}
+
+	static constexpr char SampleSourceCode[] =
+		"{\n"
+		"    function foo() -> result\n"
+		"    {\n"
+		"        let x := 1\n"
+		"        result := 15\n"
+		"    }\n"
+		"    function bar() -> result\n"
+		"    {\n"
+		"        result := 15\n"
+		"    }\n"
+		"    mstore(foo(), bar())\n"
+		"}\n";
+
+	CharStream m_sourceStream;
+	Program m_program;
+};
+
+BOOST_AUTO_TEST_SUITE(Phaser)
+BOOST_AUTO_TEST_SUITE(FitnessMetricsTest)
+BOOST_AUTO_TEST_SUITE(ProgramSizeTest)
+
+BOOST_FIXTURE_TEST_CASE(evaluate_should_compute_size_of_the_optimised_program, FitnessMetricFixture)
+{
+	Chromosome chromosome(vector<string>{UnusedPruner::name, EquivalentFunctionCombiner::name});
+
+	Program optimisedProgram = m_program;
+	optimisedProgram.optimise(chromosome.optimisationSteps());
+	assert(m_program.codeSize() != optimisedProgram.codeSize());
+
+	BOOST_TEST(ProgramSize(m_program).evaluate(chromosome) != m_program.codeSize());
+	BOOST_TEST(ProgramSize(m_program).evaluate(chromosome) == optimisedProgram.codeSize());
+}
+
+BOOST_AUTO_TEST_SUITE_END()
+BOOST_AUTO_TEST_SUITE_END()
+BOOST_AUTO_TEST_SUITE_END()
+
+}
+

tools/yulPhaser/FitnessMetrics.cpp

@@ -16,3 +16,13 @@
 */
 
 #include <tools/yulPhaser/FitnessMetrics.h>
+
+using namespace std;
+using namespace solidity::phaser;
+
+size_t ProgramSize::evaluate(Chromosome const& _chromosome) const
+{
+	Program programCopy = m_program;
+	programCopy.optimise(_chromosome.optimisationSteps());
+	return programCopy.codeSize();
+}

tools/yulPhaser/FitnessMetrics.h

@@ -21,6 +21,7 @@
 #pragma once
 
 #include <tools/yulPhaser/Chromosome.h>
+#include <tools/yulPhaser/Program.h>
 
 #include <cstddef>
 
@@ -45,4 +46,19 @@ public:
 	virtual size_t evaluate(Chromosome const& _chromosome) const = 0;
 };
 
+/**
+ * Fitness metric based on the size of a specific program after applying the optimisations from the
+ * chromosome to it.
+ */
+class ProgramSize: public FitnessMetric
+{
+public:
+	ProgramSize(Program _program): m_program(std::move(_program)) {}
+
+	size_t evaluate(Chromosome const& _chromosome) const override;
+
+private:
+	Program m_program;
+};
+
 }