Turn simplification rule tuple into struct.

libevmasm/ExpressionClasses.cpp

@@ -202,7 +202,7 @@ ExpressionClasses::Id ExpressionClasses::tryToSimplify(Expression const& _expr)
 		//cout << "with rule " << match->first.toString() << endl;
 		//ExpressionTemplate t(match->second());
 		//cout << "to " << match->second().toString() << endl;
-		return rebuildExpression(ExpressionTemplate(std::get<1>(*match)(), _expr.item->location()));
+		return rebuildExpression(ExpressionTemplate(match->action(), _expr.item->location()));
 	}
 
 	return -1;

libevmasm/RuleList.h

@@ -25,6 +25,7 @@
 #include <functional>
 
 #include <libevmasm/Instruction.h>
+#include <libevmasm/SimplificationRule.h>
 
 #include <libdevcore/CommonData.h>
 
@@ -45,12 +46,10 @@ template <class S> S modWorkaround(S const& _a, S const& _b)
 
 /// @returns a list of simplification rules given certain match placeholders.
 /// A, B and C should represent constants, X and Y arbitrary expressions.
-/// The third element in the tuple is a boolean flag that indicates whether
-/// any non-constant elements in the pattern are removed by applying it.
 /// The simplifications should neven change the order of evaluation of
-/// arbitrary operations, though.
+/// arbitrary operations.
 template <class Pattern>
-std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>> simplificationRuleList(
+std::vector<SimplificationRule<Pattern>> simplificationRuleList(
 	Pattern A,
 	Pattern B,
 	Pattern C,
@@ -58,8 +57,8 @@ std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>> simplificationR
 	Pattern Y
 )
 {
-	std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>> rules;
-	rules += std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>>{
+	std::vector<SimplificationRule<Pattern>> rules;
+	rules += std::vector<SimplificationRule<Pattern>>{
 		// arithmetics on constants
 		{{Instruction::ADD, {A, B}}, [=]{ return A.d() + B.d(); }, false},
 		{{Instruction::MUL, {A, B}}, [=]{ return A.d() * B.d(); }, false},
@@ -196,7 +195,7 @@ std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>> simplificationR
 		// xa can be (X, A) or (A, X)
 		for (auto xa: {std::vector<Pattern>{X, A}, std::vector<Pattern>{A, X}})
 		{
-			rules += std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>>{{
+			rules += std::vector<SimplificationRule<Pattern>>{{
 				// (X+A)+B -> X+(A+B)
 				{op, {{op, xa}, B}},
 				[=]() -> Pattern { return {op, {X, fun(A.d(), B.d())}}; },
@@ -221,7 +220,7 @@ std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>> simplificationR
 	}
 
 	// move constants across subtractions
-	rules += std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>>{
+	rules += std::vector<SimplificationRule<Pattern>>{
 		{
 			// X - A -> X + (-A)
 			{Instruction::SUB, {X, A}},

libevmasm/SimplificationRule.h

@@ -0,0 +1,45 @@
+/*
+	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/>.
+*/
+/**
+ * Expression simplification pattern.
+ */
+
+#pragma once
+
+#include <functional>
+
+namespace dev
+{
+namespace solidity
+{
+
+/**
+ * Rule that contains a pattern, an action that can be applied
+ * after the pattern has matched and a bool that indicates
+ * whether the action would remove something from the expression
+ * than is not a constant literal.
+ */
+template <class Pattern>
+struct SimplificationRule
+{
+	Pattern pattern;
+	std::function<Pattern()> action;
+	bool removesNonConstants;
+};
+
+}
+}

libevmasm/SimplificationRules.cpp

@@ -23,7 +23,6 @@
 
 #include <libevmasm/ExpressionClasses.h>
 #include <utility>
-#include <tuple>
 #include <functional>
 #include <boost/range/adaptor/reversed.hpp>
 #include <boost/noncopyable.hpp>
@@ -38,7 +37,7 @@ using namespace dev;
 using namespace dev::eth;
 
 
-tuple<Pattern, function<Pattern()>, bool> const* Rules::findFirstMatch(
+SimplificationRule<Pattern> const* Rules::findFirstMatch(
 	Expression const& _expr,
 	ExpressionClasses const& _classes
 )
@@ -48,22 +47,22 @@ tuple<Pattern, function<Pattern()>, bool> const* Rules::findFirstMatch(
 	assertThrow(_expr.item, OptimizerException, "");
 	for (auto const& rule: m_rules[byte(_expr.item->instruction())])
 	{
-		if (std::get<0>(rule).matches(_expr, _classes))
+		if (rule.pattern.matches(_expr, _classes))
 			return &rule;
 		resetMatchGroups();
 	}
 	return nullptr;
 }
 
-void Rules::addRules(std::vector<std::tuple<Pattern, std::function<Pattern ()>, bool>> const& _rules)
+void Rules::addRules(std::vector<SimplificationRule<Pattern>> const& _rules)
 {
 	for (auto const& r: _rules)
 		addRule(r);
 }
 
-void Rules::addRule(std::tuple<Pattern, std::function<Pattern()>, bool> const& _rule)
+void Rules::addRule(SimplificationRule<Pattern> const& _rule)
 {
-	m_rules[byte(std::get<0>(_rule).instruction())].push_back(_rule);
+	m_rules[byte(_rule.pattern.instruction())].push_back(_rule);
 }
 
 Rules::Rules()

libevmasm/SimplificationRules.h

@@ -24,6 +24,7 @@
 #pragma once
 
 #include <libevmasm/ExpressionClasses.h>
+#include <libevmasm/SimplificationRule.h>
 
 #include <functional>
 #include <vector>
@@ -47,21 +48,21 @@ public:
 
 	/// @returns a pointer to the first matching pattern and sets the match
 	/// groups accordingly.
-	std::tuple<Pattern, std::function<Pattern()>, bool> const* findFirstMatch(
+	SimplificationRule<Pattern> const* findFirstMatch(
 		Expression const& _expr,
 		ExpressionClasses const& _classes
 	);
 
 private:
-	void addRules(std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>> const& _rules);
-	void addRule(std::tuple<Pattern, std::function<Pattern()>, bool> const& _rule);
+	void addRules(std::vector<SimplificationRule<Pattern>> const& _rules);
+	void addRule(SimplificationRule<Pattern> const& _rule);
 
 	void resetMatchGroups() { m_matchGroups.clear(); }
 
 	std::map<unsigned, Expression const*> m_matchGroups;
 	/// Pattern to match, replacement to be applied and flag indicating whether
 	/// the replacement might remove some elements (except constants).
-	std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>> m_rules[256];
+	std::vector<SimplificationRule<Pattern>> m_rules[256];
 };
 
 /**

libjulia/optimiser/ExpressionSimplifier.cpp

@@ -43,8 +43,8 @@ void ExpressionSimplifier::visit(Expression& _expression)
 		// Do not apply the rule if it removes non-constant parts of the expression.
 		// TODO: The check could actually be less strict than "movable".
 		// We only require "Does not cause side-effects".
-		if (std::get<2>(*match) && !MovableChecker(_expression).movable())
+		if (match->removesNonConstants && !MovableChecker(_expression).movable())
 			return;
-		_expression = std::get<1>(*match)().toExpression(locationOf(_expression));
+		_expression = match->action().toExpression(locationOf(_expression));
 	}
 }

libjulia/optimiser/SimplificationRules.cpp

@@ -34,7 +34,7 @@ using namespace dev;
 using namespace dev::julia;
 
 
-tuple<Pattern, function<Pattern()>, bool> const* SimplificationRules::findFirstMatch(Expression const& _expr)
+SimplificationRule<Pattern> const* SimplificationRules::findFirstMatch(Expression const& _expr)
 {
 	if (_expr.type() != typeid(FunctionalInstruction))
 		return nullptr;
@@ -45,21 +45,21 @@ tuple<Pattern, function<Pattern()>, bool> const* SimplificationRules::findFirstM
 	for (auto const& rule: rules.m_rules[byte(instruction.instruction)])
 	{
 		rules.resetMatchGroups();
-		if (std::get<0>(rule).matches(_expr))
+		if (rule.pattern.matches(_expr))
 			return &rule;
 	}
 	return nullptr;
 }
 
-void SimplificationRules::addRules(vector<tuple<Pattern, function<Pattern()>, bool>> const& _rules)
+void SimplificationRules::addRules(vector<SimplificationRule<Pattern>> const& _rules)
 {
 	for (auto const& r: _rules)
 		addRule(r);
 }
 
-void SimplificationRules::addRule(tuple<Pattern, function<Pattern()>, bool> const& _rule)
+void SimplificationRules::addRule(SimplificationRule<Pattern> const& _rule)
 {
-	m_rules[byte(std::get<0>(_rule).instruction())].push_back(_rule);
+	m_rules[byte(_rule.pattern.instruction())].push_back(_rule);
 }
 
 SimplificationRules::SimplificationRules()

libjulia/optimiser/SimplificationRules.h

@@ -21,6 +21,7 @@
 #pragma once
 
 #include <libevmasm/ExpressionClasses.h>
+#include <libevmasm/SimplificationRule.h>
 
 #include <libjulia/ASTDataForward.h>
 
@@ -48,16 +49,16 @@ public:
 
 	/// @returns a pointer to the first matching pattern and sets the match
 	/// groups accordingly.
-	static std::tuple<Pattern, std::function<Pattern()>, bool> const* findFirstMatch(Expression const& _expr);
+	static SimplificationRule<Pattern> const* findFirstMatch(Expression const& _expr);
 
 private:
-	void addRules(std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>> const& _rules);
-	void addRule(std::tuple<Pattern, std::function<Pattern()>, bool> const& _rule);
+	void addRules(std::vector<SimplificationRule<Pattern>> const& _rules);
+	void addRule(SimplificationRule<Pattern> const& _rule);
 
 	void resetMatchGroups() { m_matchGroups.clear(); }
 
 	std::map<unsigned, Expression const*> m_matchGroups;
-	std::vector<std::tuple<Pattern, std::function<Pattern()>, bool>> m_rules[256];
+	std::vector<SimplificationRule<Pattern>> m_rules[256];
 };
 
 enum class PatternKind