1 files changed, 136 insertions, 0 deletions
diff --git a/libsolidity/analysis/ControlFlowGraph.cpp b/libsolidity/analysis/ControlFlowGraph.cpp
new file mode 100644
index 00000000..9b3da0eb
--- /dev/null
+++ b/libsolidity/analysis/ControlFlowGraph.cpp
@@ -0,0 +1,136 @@
+/*
+	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 <libsolidity/analysis/ControlFlowGraph.h>
+#include <libsolidity/analysis/ControlFlowBuilder.h>
+
+#include <boost/range/adaptor/reversed.hpp>
+
+#include <algorithm>
+
+using namespace std;
+using namespace dev::solidity;
+
+bool CFG::constructFlow(ASTNode const& _astRoot)
+{
+	_astRoot.accept(*this);
+	applyModifiers();
+	return Error::containsOnlyWarnings(m_errorReporter.errors());
+}
+
+
+bool CFG::visit(ModifierDefinition const& _modifier)
+{
+	m_modifierControlFlow[&_modifier] = ControlFlowBuilder::createModifierFlow(m_nodeContainer, _modifier);
+	return false;
+}
+
+bool CFG::visit(FunctionDefinition const& _function)
+{
+	m_functionControlFlow[&_function] = ControlFlowBuilder::createFunctionFlow(m_nodeContainer, _function);
+	return false;
+}
+
+FunctionFlow const& CFG::functionFlow(FunctionDefinition const& _function) const
+{
+	solAssert(m_functionControlFlow.count(&_function), "");
+	return *m_functionControlFlow.find(&_function)->second;
+}
+
+CFGNode* CFG::NodeContainer::newNode()
+{
+	m_nodes.emplace_back(new CFGNode());
+	return m_nodes.back().get();
+}
+
+void CFG::applyModifiers()
+{
+	for (auto const& function: m_functionControlFlow)
+	{
+		for (auto const& modifierInvocation: boost::adaptors::reverse(function.first->modifiers()))
+		{
+			if (auto modifierDefinition = dynamic_cast<ModifierDefinition const*>(
+				modifierInvocation->name()->annotation().referencedDeclaration
+			))
+			{
+				solAssert(m_modifierControlFlow.count(modifierDefinition), "");
+				applyModifierFlowToFunctionFlow(*m_modifierControlFlow[modifierDefinition], function.second.get());
+			}
+		}
+	}
+}
+
+void CFG::applyModifierFlowToFunctionFlow(
+	ModifierFlow const& _modifierFlow,
+	FunctionFlow* _functionFlow
+)
+{
+	solAssert(!!_functionFlow, "");
+
+	map<CFGNode*, CFGNode*> copySrcToCopyDst;
+
+	// inherit the revert node of the function
+	copySrcToCopyDst[_modifierFlow.revert] = _functionFlow->revert;
+
+	// replace the placeholder nodes by the function entry and exit
+	copySrcToCopyDst[_modifierFlow.placeholderEntry] = _functionFlow->entry;
+	copySrcToCopyDst[_modifierFlow.placeholderExit] = _functionFlow->exit;
+
+	stack<CFGNode*> nodesToCopy;
+	nodesToCopy.push(_modifierFlow.entry);
+
+	// map the modifier entry to a new node that will become the new function entry
+	copySrcToCopyDst[_modifierFlow.entry] = m_nodeContainer.newNode();
+
+	while (!nodesToCopy.empty())
+	{
+		CFGNode* copySrcNode = nodesToCopy.top();
+		nodesToCopy.pop();
+
+		solAssert(copySrcToCopyDst.count(copySrcNode), "");
+
+		CFGNode* copyDstNode = copySrcToCopyDst[copySrcNode];
+
+		copyDstNode->block = copySrcNode->block;
+		for (auto const& entry: copySrcNode->entries)
+		{
+			if (!copySrcToCopyDst.count(entry))
+			{
+				copySrcToCopyDst[entry] = m_nodeContainer.newNode();
+				nodesToCopy.push(entry);
+			}
+			copyDstNode->entries.emplace_back(copySrcToCopyDst[entry]);
+		}
+		for (auto const& exit: copySrcNode->exits)
+		{
+			if (!copySrcToCopyDst.count(exit))
+			{
+				copySrcToCopyDst[exit] = m_nodeContainer.newNode();
+				nodesToCopy.push(exit);
+			}
+			copyDstNode->exits.emplace_back(copySrcToCopyDst[exit]);
+		}
+	}
+
+	// if the modifier control flow never reached its exit node,
+	// we need to create a new (disconnected) exit node now
+	if (!copySrcToCopyDst.count(_modifierFlow.exit))
+		copySrcToCopyDst[_modifierFlow.exit] = m_nodeContainer.newNode();
+
+	_functionFlow->entry = copySrcToCopyDst[_modifierFlow.entry];
+	_functionFlow->exit = copySrcToCopyDst[_modifierFlow.exit];
+}
+\ No newline at end of file