[yul-phaser] Add geneRandomisation(), geneDeletion(), geneAddition and alternativeMutations()

test/CMakeLists.txt

@@ -145,6 +145,7 @@ set(yul_phaser_sources
     yulPhaser/Chromosome.cpp
     yulPhaser/FitnessMetrics.cpp
     yulPhaser/GeneticAlgorithms.cpp
+    yulPhaser/Mutations.cpp
     yulPhaser/PairSelections.cpp
     yulPhaser/Population.cpp
     yulPhaser/Program.cpp

test/yulPhaser/Mutations.cpp

@@ -0,0 +1,219 @@
+/*
+	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 <test/yulPhaser/Common.h>
+
+#include <tools/yulPhaser/Mutations.h>
+
+#include <tools/yulPhaser/SimulationRNG.h>
+
+#include <boost/test/unit_test.hpp>
+
+#include <algorithm>
+#include <vector>
+
+using namespace std;
+
+namespace solidity::phaser::test
+{
+
+BOOST_AUTO_TEST_SUITE(Phaser)
+BOOST_AUTO_TEST_SUITE(MutationsTest)
+BOOST_AUTO_TEST_SUITE(GeneRandomisationTest)
+
+BOOST_AUTO_TEST_CASE(geneRandomisation_should_iterate_over_genes_and_replace_them_with_random_ones_with_given_probability)
+{
+	Chromosome chromosome("fcCUnDvejs");
+	function<Mutation> mutation01 = geneRandomisation(0.1);
+	function<Mutation> mutation05 = geneRandomisation(0.5);
+	function<Mutation> mutation10 = geneRandomisation(1.0);
+
+	SimulationRNG::reset(1);
+	BOOST_TEST(countDifferences(mutation01(chromosome), chromosome), 2);
+	BOOST_TEST(countDifferences(mutation05(chromosome), chromosome), 5);
+	BOOST_TEST(countDifferences(mutation10(chromosome), chromosome), 7);
+	SimulationRNG::reset(2);
+	BOOST_TEST(countDifferences(mutation01(chromosome), chromosome), 1);
+	BOOST_TEST(countDifferences(mutation05(chromosome), chromosome), 3);
+	BOOST_TEST(countDifferences(mutation10(chromosome), chromosome), 9);
+}
+
+BOOST_AUTO_TEST_CASE(geneRandomisation_should_return_identical_chromosome_if_probability_is_zero)
+{
+	Chromosome chromosome("fcCUnDvejsrmV");
+	function<Mutation> mutation = geneRandomisation(0.0);
+
+	BOOST_TEST(mutation(chromosome) == chromosome);
+}
+
+BOOST_AUTO_TEST_CASE(geneDeletion_should_iterate_over_genes_and_delete_them_with_given_probability)
+{
+	Chromosome chromosome("fcCUnDvejs");
+	function<Mutation> mutation01 = geneDeletion(0.1);
+	function<Mutation> mutation05 = geneDeletion(0.5);
+
+	SimulationRNG::reset(1);
+	//                                                               fcCUnDvejs
+	BOOST_TEST(mutation01(chromosome) == Chromosome(stripWhitespace("fcCU Dvejs")));
+	BOOST_TEST(mutation05(chromosome) == Chromosome(stripWhitespace("     D ejs")));
+	SimulationRNG::reset(2);
+	BOOST_TEST(mutation01(chromosome) == Chromosome(stripWhitespace("fcUnDvejs")));
+	BOOST_TEST(mutation05(chromosome) == Chromosome(stripWhitespace("  Un    s")));
+}
+
+BOOST_AUTO_TEST_CASE(geneDeletion_should_return_identical_chromosome_if_probability_is_zero)
+{
+	Chromosome chromosome("fcCUnDvejsrmV");
+	function<Mutation> mutation = geneDeletion(0.0);
+
+	BOOST_TEST(mutation(chromosome) == chromosome);
+}
+
+BOOST_AUTO_TEST_CASE(geneDeletion_should_delete_all_genes_if_probability_is_one)
+{
+	Chromosome chromosome("fcCUnDvejsrmV");
+	function<Mutation> mutation = geneDeletion(1.0);
+
+	BOOST_TEST(mutation(chromosome) == Chromosome(""));
+}
+
+BOOST_AUTO_TEST_CASE(geneAddition_should_iterate_over_gene_positions_and_insert_new_genes_with_given_probability)
+{
+	Chromosome chromosome("fcCUnDvejs");
+	function<Mutation> mutation01 = geneAddition(0.1);
+	function<Mutation> mutation05 = geneAddition(0.5);
+
+	SimulationRNG::reset(1);
+	//                                                                 f  c  C  U  n  D  v  e  j  s
+	BOOST_TEST(mutation01(chromosome) == Chromosome(stripWhitespace("  f  c  C  UC n  D  v  e  jx s")));  //  20% more
+	BOOST_TEST(mutation05(chromosome) == Chromosome(stripWhitespace("j f  cu C  U  ne D  v  eI j  sf"))); //  50% more
+	SimulationRNG::reset(2);
+	BOOST_TEST(mutation01(chromosome) == Chromosome(stripWhitespace("  f  cu C  U  n  D  v  e  j  s")));  //  10% more
+	BOOST_TEST(mutation05(chromosome) == Chromosome(stripWhitespace("L f  ce Cv U  n  D  v  e  jO s")));  //  40% more
+}
+
+BOOST_AUTO_TEST_CASE(geneAddition_should_be_able_to_insert_before_first_position)
+{
+	SimulationRNG::reset(7);
+	Chromosome chromosome("fcCUnDvejs");
+	function<Mutation> mutation = geneAddition(0.1);
+
+	Chromosome mutatedChromosome = mutation(chromosome);
+	BOOST_TEST(mutatedChromosome.length() > chromosome.length());
+
+	vector<string> suffix(
+		mutatedChromosome.optimisationSteps().end() - chromosome.length(),
+		mutatedChromosome.optimisationSteps().end()
+	);
+	BOOST_TEST(suffix == chromosome.optimisationSteps());
+}
+
+BOOST_AUTO_TEST_CASE(geneAddition_should_be_able_to_insert_after_last_position)
+{
+	SimulationRNG::reset(81);
+	Chromosome chromosome("fcCUnDvejs");
+	function<Mutation> mutation = geneAddition(0.1);
+
+	Chromosome mutatedChromosome = mutation(chromosome);
+	BOOST_TEST(mutatedChromosome.length() > chromosome.length());
+
+	vector<string> prefix(
+		mutatedChromosome.optimisationSteps().begin(),
+		mutatedChromosome.optimisationSteps().begin() + chromosome.length()
+	);
+	BOOST_TEST(prefix == chromosome.optimisationSteps());
+}
+
+BOOST_AUTO_TEST_CASE(geneAddition_should_return_identical_chromosome_if_probability_is_zero)
+{
+	Chromosome chromosome("fcCUnDvejsrmV");
+	function<Mutation> mutation = geneAddition(0.0);
+
+	BOOST_TEST(mutation(chromosome) == chromosome);
+}
+
+BOOST_AUTO_TEST_CASE(geneAddition_should_insert_genes_at_all_positions_if_probability_is_one)
+{
+	Chromosome chromosome("fcCUnDvejsrmV");
+	function<Mutation> mutation = geneAddition(1.0);
+
+	Chromosome mutatedChromosome = mutation(chromosome);
+	BOOST_TEST(mutatedChromosome.length() == chromosome.length() * 2 + 1);
+
+	vector<string> originalGenes;
+	for (size_t i = 0; i < mutatedChromosome.length() - 1; ++i)
+		if (i % 2 == 1)
+			originalGenes.push_back(mutatedChromosome.optimisationSteps()[i]);
+
+	BOOST_TEST(Chromosome(originalGenes) == chromosome);
+}
+
+BOOST_AUTO_TEST_CASE(alternativeMutations_should_choose_between_mutations_with_given_probability)
+{
+	SimulationRNG::reset(1);
+	Chromosome chromosome("a");
+	function<Mutation> mutation = alternativeMutations(
+		0.8,
+		wholeChromosomeReplacement(Chromosome("c")),
+		wholeChromosomeReplacement(Chromosome("f"))
+	);
+
+	size_t cCount = 0;
+	size_t fCount = 0;
+	for (size_t i = 0; i < 10; ++i)
+	{
+		Chromosome mutatedChromosome = mutation(chromosome);
+		cCount += static_cast<int>(mutatedChromosome == Chromosome("c"));
+		fCount += static_cast<int>(mutatedChromosome == Chromosome("f"));
+	}
+
+	// This particular seed results in 7 "c"s out of 10 which looks plausible given the 80% chance.
+	BOOST_TEST(cCount == 7);
+	BOOST_TEST(fCount == 3);
+}
+
+BOOST_AUTO_TEST_CASE(alternativeMutations_should_always_choose_first_mutation_if_probability_is_one)
+{
+	Chromosome chromosome("a");
+	function<Mutation> mutation = alternativeMutations(
+		1.0,
+		wholeChromosomeReplacement(Chromosome("c")),
+		wholeChromosomeReplacement(Chromosome("f"))
+	);
+
+	for (size_t i = 0; i < 10; ++i)
+		BOOST_TEST(mutation(chromosome) == Chromosome("c"));
+}
+
+BOOST_AUTO_TEST_CASE(alternativeMutations_should_always_choose_second_mutation_if_probability_is_zero)
+{
+	Chromosome chromosome("a");
+	function<Mutation> mutation = alternativeMutations(
+		0.0,
+		wholeChromosomeReplacement(Chromosome("c")),
+		wholeChromosomeReplacement(Chromosome("f"))
+	);
+
+	for (size_t i = 0; i < 10; ++i)
+		BOOST_TEST(mutation(chromosome) == Chromosome("f"));
+}
+
+BOOST_AUTO_TEST_SUITE_END()
+BOOST_AUTO_TEST_SUITE_END()
+BOOST_AUTO_TEST_SUITE_END()
+
+}

tools/CMakeLists.txt

@@ -23,6 +23,8 @@ add_executable(yul-phaser
 	yulPhaser/FitnessMetrics.cpp
 	yulPhaser/Chromosome.h
 	yulPhaser/Chromosome.cpp
+	yulPhaser/Mutations.h
+	yulPhaser/Mutations.cpp
 	yulPhaser/PairSelections.h
 	yulPhaser/PairSelections.cpp
 	yulPhaser/Selections.h

tools/yulPhaser/Mutations.cpp

@@ -0,0 +1,91 @@
+/*
+	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/Mutations.h>
+
+#include <tools/yulPhaser/SimulationRNG.h>
+
+#include <string>
+#include <vector>
+
+using namespace std;
+using namespace solidity;
+using namespace solidity::phaser;
+
+function<Mutation> phaser::geneRandomisation(double _chance)
+{
+	return [=](Chromosome const& _chromosome)
+	{
+		vector<string> optimisationSteps;
+		for (auto const& step: _chromosome.optimisationSteps())
+			optimisationSteps.push_back(
+				SimulationRNG::bernoulliTrial(_chance) ?
+				Chromosome::randomOptimisationStep() :
+				step
+			);
+
+		return Chromosome(move(optimisationSteps));
+	};
+}
+
+function<Mutation> phaser::geneDeletion(double _chance)
+{
+	return [=](Chromosome const& _chromosome)
+	{
+		vector<string> optimisationSteps;
+		for (auto const& step: _chromosome.optimisationSteps())
+			if (!SimulationRNG::bernoulliTrial(_chance))
+				optimisationSteps.push_back(step);
+
+		return Chromosome(move(optimisationSteps));
+	};
+}
+
+function<Mutation> phaser::geneAddition(double _chance)
+{
+	return [=](Chromosome const& _chromosome)
+	{
+		vector<string> optimisationSteps;
+
+		if (SimulationRNG::bernoulliTrial(_chance))
+			optimisationSteps.push_back(Chromosome::randomOptimisationStep());
+
+		for (auto const& step: _chromosome.optimisationSteps())
+		{
+			optimisationSteps.push_back(step);
+			if (SimulationRNG::bernoulliTrial(_chance))
+				optimisationSteps.push_back(Chromosome::randomOptimisationStep());
+		}
+
+		return Chromosome(move(optimisationSteps));
+	};
+}
+
+function<Mutation> phaser::alternativeMutations(
+	double _firstMutationChance,
+	function<Mutation> _mutation1,
+	function<Mutation> _mutation2
+)
+{
+	return [=](Chromosome const& _chromosome)
+	{
+		if (SimulationRNG::bernoulliTrial(_firstMutationChance))
+			return _mutation1(_chromosome);
+		else
+			return _mutation2(_chromosome);
+	};
+}

tools/yulPhaser/Mutations.h

@@ -0,0 +1,56 @@
+/*
+	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/>.
+*/
+/**
+ * Mutation and crossover operators for use in genetic algorithms.
+ */
+
+#pragma once
+
+#include <tools/yulPhaser/Chromosome.h>
+
+#include <functional>
+
+namespace solidity::phaser
+{
+
+using Mutation = Chromosome(Chromosome const&);
+
+// MUTATIONS
+
+/// Creates a mutation operator that iterates over all genes in a chromosome and with probability
+/// @a _chance replaces a gene with a random one (which could also be the same as the original).
+std::function<Mutation> geneRandomisation(double _chance);
+
+/// Creates a mutation operator that iterates over all genes in a chromosome and with probability
+/// @a _chance deletes it.
+std::function<Mutation> geneDeletion(double _chance);
+
+/// Creates a mutation operator that iterates over all positions in a chromosome (including spots
+/// at the beginning and at the end of the sequence) and with probability @a _chance insert a new,
+/// randomly chosen gene.
+std::function<Mutation> geneAddition(double _chance);
+
+/// Creates a mutation operator that always applies one of the mutations passed to it.
+/// The probability that the chosen mutation is the first one is @a _firstMutationChance.
+/// randomly chosen gene.
+std::function<Mutation> alternativeMutations(
+	double _firstMutationChance,
+	std::function<Mutation> _mutation1,
+	std::function<Mutation> _mutation2
+);
+
+}