Remove VarDeclPropagator.

libyul/CMakeLists.txt

@@ -43,7 +43,6 @@ add_library(yul
 	optimiser/SyntacticalEquality.cpp
 	optimiser/UnusedPruner.cpp
 	optimiser/Utilities.cpp
-	optimiser/VarDeclPropagator.cpp
 	optimiser/VarDeclInitializer.cpp
 )
 target_link_libraries(yul PUBLIC evmasm devcore langutil)

libyul/optimiser/Suite.cpp

@@ -36,7 +36,6 @@
 #include <libyul/optimiser/SSATransform.h>
 #include <libyul/optimiser/StructuralSimplifier.h>
 #include <libyul/optimiser/RedundantAssignEliminator.h>
-#include <libyul/optimiser/VarDeclPropagator.h>
 #include <libyul/AsmAnalysisInfo.h>
 #include <libyul/AsmData.h>
 #include <libyul/AsmPrinter.h>
@@ -70,7 +69,6 @@ void OptimiserSuite::run(
 		ExpressionSplitter{dispenser}(ast);
 		SSATransform::run(ast, dispenser);
 		RedundantAssignEliminator::run(ast);
-		VarDeclPropagator{}(ast);
 		RedundantAssignEliminator::run(ast);
 
 		CommonSubexpressionEliminator{}(ast);
@@ -97,27 +95,22 @@ void OptimiserSuite::run(
 		RedundantAssignEliminator::run(ast);
 		CommonSubexpressionEliminator{}(ast);
 		FullInliner{ast, dispenser}.run();
-		VarDeclPropagator{}(ast);
 		SSATransform::run(ast, dispenser);
 		RedundantAssignEliminator::run(ast);
-		VarDeclPropagator{}(ast);
 		RedundantAssignEliminator::run(ast);
 		ExpressionSimplifier::run(ast);
 		StructuralSimplifier{}(ast);
 		CommonSubexpressionEliminator{}(ast);
 		SSATransform::run(ast, dispenser);
 		RedundantAssignEliminator::run(ast);
-		VarDeclPropagator{}(ast);
 		RedundantAssignEliminator::run(ast);
 		UnusedPruner::runUntilStabilised(ast, reservedIdentifiers);
 	}
 	ExpressionJoiner::run(ast);
-	VarDeclPropagator{}(ast);
 	UnusedPruner::runUntilStabilised(ast);
 	ExpressionJoiner::run(ast);
 	UnusedPruner::runUntilStabilised(ast);
 	ExpressionJoiner::run(ast);
-	VarDeclPropagator{}(ast);
 	UnusedPruner::runUntilStabilised(ast);
 	ExpressionJoiner::run(ast);
 	UnusedPruner::runUntilStabilised(ast);

libyul/optimiser/VarDeclPropagator.cpp

@@ -1,126 +0,0 @@
-/*
-	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 <libyul/optimiser/VarDeclPropagator.h>
-#include <libyul/AsmData.h>
-#include <libdevcore/CommonData.h>
-#include <boost/range/algorithm_ext/erase.hpp>
-#include <algorithm>
-#include <map>
-
-using namespace std;
-using namespace dev;
-using namespace yul;
-
-void VarDeclPropagator::operator()(Block& _block)
-{
-	map<YulString, TypedName> outerEmptyVarDecls;
-	map<YulString, TypedName> outerLazyInitializedVarDecls;
-	swap(m_emptyVarDecls, outerEmptyVarDecls);
-	swap(m_lazyInitializedVarDecls, outerLazyInitializedVarDecls);
-
-	ASTModifier::operator()(_block);
-
-	iterateReplacing(
-		_block.statements,
-		[this](Statement& _stmt) -> boost::optional<vector<Statement>>
-		{
-			if (_stmt.type() == typeid(VariableDeclaration))
-			{
-				VariableDeclaration& varDecl = boost::get<VariableDeclaration>(_stmt);
-				boost::remove_erase_if(
-					varDecl.variables,
-					[&](TypedName const& _typedName) { return m_lazyInitializedVarDecls.count(_typedName.name); }
-				);
-				if (varDecl.variables.empty())
-					return vector<Statement>{};
-				else
-					return {};
-			}
-			else if (_stmt.type() == typeid(Assignment))
-			{
-				Assignment& assignment = boost::get<Assignment>(_stmt);
-				if (isFullyLazyInitialized(assignment.variableNames))
-					return vector<Statement>{recreateVariableDeclaration(assignment)};
-				else
-					return {};
-			}
-			else
-				return {};
-		}
-	);
-
-	swap(m_emptyVarDecls, outerEmptyVarDecls);
-	swap(m_lazyInitializedVarDecls, outerLazyInitializedVarDecls);
-}
-
-void VarDeclPropagator::operator()(VariableDeclaration& _varDecl)
-{
-	if (_varDecl.value)
-		visit(*_varDecl.value);
-	else
-		for (TypedName const& typedName: _varDecl.variables)
-			m_emptyVarDecls[typedName.name] = typedName;
-}
-
-void VarDeclPropagator::operator()(Assignment& _assignment)
-{
-	visit(*_assignment.value);
-
-	if (allVarNamesUninitialized(_assignment.variableNames))
-		for (Identifier const& ident: _assignment.variableNames)
-			m_lazyInitializedVarDecls[ident.name] = m_emptyVarDecls[ident.name];
-
-	for (Identifier& name: _assignment.variableNames)
-		(*this)(name);
-}
-
-void VarDeclPropagator::operator()(Identifier& _ident)
-{
-	m_emptyVarDecls.erase(_ident.name);
-}
-
-bool VarDeclPropagator::allVarNamesUninitialized(vector<Identifier> const& _variableNames) const
-{
-	return all_of(
-		begin(_variableNames),
-		end(_variableNames),
-		[&](Identifier const& _ident) -> bool { return m_emptyVarDecls.count(_ident.name); }
-	);
-}
-
-bool VarDeclPropagator::isFullyLazyInitialized(vector<Identifier> const& _variableNames) const
-{
-	return all_of(
-		begin(_variableNames),
-		end(_variableNames),
-		[&](Identifier const& ident) -> bool { return m_lazyInitializedVarDecls.count(ident.name); }
-	);
-}
-
-VariableDeclaration VarDeclPropagator::recreateVariableDeclaration(Assignment& _assignment)
-{
-	TypedNameList variables;
-
-	for (Identifier const& varName: _assignment.variableNames)
-	{
-		variables.emplace_back(move(m_lazyInitializedVarDecls.at(varName.name)));
-		m_lazyInitializedVarDecls.erase(varName.name);
-	}
-
-	return VariableDeclaration{move(_assignment.location), move(variables), std::move(_assignment.value)};
-}

libyul/optimiser/VarDeclPropagator.h

@@ -1,60 +0,0 @@
-/*
-	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/>.
-*/
-
-#pragma once
-
-#include <libyul/AsmDataForward.h>
-#include <libyul/optimiser/ASTWalker.h>
-#include <libyul/Exceptions.h>
-#include <libyul/AsmDataForward.h>
-#include <vector>
-#include <set>
-#include <map>
-
-namespace yul
-{
-
-/**
- * Rewrites Assignment statements into VariableDeclaration when the assignment's LHS
- * variables had no value yet.
- *
- * It recursively walks through the AST and moves each declaration of variables to
- * the first assignment within the same block (if possible)..
- */
-class VarDeclPropagator: public ASTModifier
-{
-public:
-	using ASTModifier::operator();
-	void operator()(Block& _block) override;
-	void operator()(VariableDeclaration& _varDecl) override;
-	void operator()(Assignment& _assignment) override;
-	void operator()(Identifier& _ident) override;
-
-private:
-	bool allVarNamesUninitialized(std::vector<Identifier> const& _variableNames) const;
-	bool isFullyLazyInitialized(std::vector<Identifier> const& _variableNames) const;
-	VariableDeclaration recreateVariableDeclaration(Assignment& _assignment);
-
-private:
-	/// Holds a list of variables from current Block that have no value assigned yet.
-	std::map<YulString, TypedName> m_emptyVarDecls;
-
-	/// Holds a list variables (and their TypedName) within the current block.
-	std::map<YulString, TypedName> m_lazyInitializedVarDecls;
-};
-
-}

test/libyul/YulOptimizerTest.cpp

@@ -22,7 +22,6 @@
 #include <test/Options.h>
 
 #include <libyul/optimiser/BlockFlattener.h>
-#include <libyul/optimiser/VarDeclPropagator.h>
 #include <libyul/optimiser/VarDeclInitializer.h>
 #include <libyul/optimiser/Disambiguator.h>
 #include <libyul/optimiser/CommonSubexpressionEliminator.h>
@@ -108,11 +107,6 @@ bool YulOptimizerTest::run(ostream& _stream, string const& _linePrefix, bool con
 		disambiguate();
 		BlockFlattener{}(*m_ast);
 	}
-	else if (m_optimizerStep == "varDeclPropagator")
-	{
-		disambiguate();
-		VarDeclPropagator{}(*m_ast);
-	}
 	else if (m_optimizerStep == "varDeclInitializer")
 		VarDeclInitializer{}(*m_ast);
 	else if (m_optimizerStep == "forLoopInitRewriter")

test/libyul/yulOptimizerTests/varDeclPropagator/init_assignment_inside_if.yul

@@ -1,17 +0,0 @@
-{
-  let a := 4
-  let x
-  if a {
-    x := 2
-  }
-}
-// ----
-// varDeclPropagator
-// {
-//     let a := 4
-//     let x
-//     if a
-//     {
-//         x := 2
-//     }
-// }

test/libyul/yulOptimizerTests/varDeclPropagator/multi_assignment_vardecl.yul

@@ -1,13 +0,0 @@
-{
-  function f() -> a, b, c {}
-  let x, y, z
-  z, x, y := f()
-}
-// ----
-// varDeclPropagator
-// {
-//     function f() -> a, b, c
-//     {
-//     }
-//     let z, x, y := f()
-// }

test/libyul/yulOptimizerTests/varDeclPropagator/overwrite.yul

@@ -1,11 +0,0 @@
-{
-  let a
-  a := 4
-  a := 5
-}
-// ----
-// varDeclPropagator
-// {
-//     let a := 4
-//     a := 5
-// }

test/libyul/yulOptimizerTests/varDeclPropagator/rewrite_removes_unused_var.yul

@@ -1,10 +0,0 @@
-{
-  let a, b
-  a := mload(0)
-}
-// ----
-// varDeclPropagator
-// {
-//     let b
-//     let a := mload(0)
-// }

test/libyul/yulOptimizerTests/varDeclPropagator/simple1.yul

@@ -1,9 +0,0 @@
-{
-  let f
-  f := mload(0)
-}
-// ----
-// varDeclPropagator
-// {
-//     let f := mload(0)
-// }

test/libyul/yulOptimizerTests/varDeclPropagator/split_assign_splits_vardecl.yul

@@ -1,11 +0,0 @@
-{
-  let a, b
-  a := mload(0)
-  b := mload(1)
-}
-// ----
-// varDeclPropagator
-// {
-//     let a := mload(0)
-//     let b := mload(1)
-// }

test/libyul/yulOptimizerTests/varDeclPropagator/use_before_init.yul

@@ -1,12 +0,0 @@
-{
-	let b
-	let a := b
-	b := 1
-}
-// ----
-// varDeclPropagator
-// {
-//     let b
-//     let a := b
-//     b := 1
-// }

test/libyul/yulOptimizerTests/varDeclPropagator/use_doesnt_rewrite.yul

@@ -1,16 +0,0 @@
-{
-  function f(x) {}
-  let a
-  f(a)
-  a := 4
-}
-// ----
-// varDeclPropagator
-// {
-//     function f(x)
-//     {
-//     }
-//     let a
-//     f(a)
-//     a := 4
-// }

test/tools/yulopti.cpp

@@ -47,7 +47,7 @@
 #include <libyul/optimiser/RedundantAssignEliminator.h>
 #include <libyul/optimiser/SSATransform.h>
 #include <libyul/optimiser/StructuralSimplifier.h>
-#include <libyul/optimiser/VarDeclPropagator.h>
+#include <libyul/optimiser/VarDeclInitializer.h>
 
 #include <libyul/backends/evm/EVMDialect.h>
 
@@ -125,7 +125,7 @@ public:
 				m_nameDispenser = make_shared<NameDispenser>(*m_ast);
 				disambiguated = true;
 			}
-			cout << "(q)quit/(f)flatten/(c)se/propagate var(d)ecls/(x)plit/(j)oin/(g)rouper/(h)oister/" << endl;
+			cout << "(q)quit/(f)flatten/(c)se/initialize var(d)ecls/(x)plit/(j)oin/(g)rouper/(h)oister/" << endl;
 			cout << "  (e)xpr inline/(i)nline/(s)implify/(u)nusedprune/ss(a) transform/" << endl;
 			cout << "  (r)edundant assign elim./re(m)aterializer/f(o)r-loop-pre-rewriter/" << endl;
 			cout << "  s(t)ructural simplifier? " << endl;
@@ -146,7 +146,7 @@ public:
 				(CommonSubexpressionEliminator{})(*m_ast);
 				break;
 			case 'd':
-				(VarDeclPropagator{})(*m_ast);
+				(VarDeclInitializer{})(*m_ast);
 				break;
 			case 'x':
 				ExpressionSplitter{*m_nameDispenser}(*m_ast);