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

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
+);
+
+}