Refactor compiler to avoid weird swap of contexts

1 files changed, 134 insertions, 0 deletions

diff --git a/libsolidity/codegen/ContractCompiler.h b/libsolidity/codegen/ContractCompiler.h
new file mode 100644
index 00000000..d1517e88
--- /dev/null
+++ b/libsolidity/codegen/ContractCompiler.h
@@ -0,0 +1,134 @@
+/*
+	This file is part of cpp-ethereum.
+
+	cpp-ethereum 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.
+
+	cpp-ethereum 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 cpp-ethereum.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @author Christian <c@ethdev.com>
+ * @date 2014
+ * Code generator for contracts.
+ */
+
+#pragma once
+
+#include <ostream>
+#include <functional>
+#include <libsolidity/ast/ASTVisitor.h>
+#include <libsolidity/codegen/CompilerContext.h>
+#include <libevmasm/Assembly.h>
+
+namespace dev {
+namespace solidity {
+
+/**
+ * Code generator at the contract level. Can be used to generate code for exactly one contract
+ * either either in "runtime mode" or "creation mode".
+ */
+class ContractCompiler: private ASTConstVisitor
+{
+public:
+	explicit ContractCompiler(CompilerContext& _context, bool _optimise):
+		m_optimise(_optimise),
+		m_context(_context),
+		m_returnTag(eth::Tag, u256(-1))
+	{
+		m_context = CompilerContext();
+		m_returnTag = m_context.newTag();
+	}
+
+	void compileContract(
+		ContractDefinition const& _contract,
+		std::map<ContractDefinition const*, eth::Assembly const*> const& _contracts
+	);
+	/// Compiles the constructor part of the contract.
+	/// @returns the identifier of the runtime sub-assembly.
+	size_t compileConstructor(
+		CompilerContext const& _runtimeContext,
+		ContractDefinition const& _contract,
+		std::map<ContractDefinition const*, eth::Assembly const*> const& _contracts
+	);
+	/// Compiles a contract that uses DELEGATECALL to call into a pre-deployed version of the given
+	/// contract at runtime, but contains the full creation-time code.
+	/// @returns the identifier of the runtime sub-assembly.
+	size_t compileClone(
+		ContractDefinition const& _contract,
+		std::map<ContractDefinition const*, eth::Assembly const*> const& _contracts
+	);
+
+private:
+	/// Registers the non-function objects inside the contract with the context and stores the basic
+	/// information about the contract like the AST annotations.
+	void initializeContext(
+		ContractDefinition const& _contract,
+		std::map<ContractDefinition const*, eth::Assembly const*> const& _compiledContracts
+	);
+	/// Adds the code that is run at creation time. Should be run after exchanging the run-time context
+	/// with a new and initialized context. Adds the constructor code.
+	/// @returns the identifier of the runtime sub assembly
+	size_t packIntoContractCreator(ContractDefinition const& _contract, CompilerContext const& _runtimeContext);
+	/// Appends state variable initialisation and constructor code.
+	void appendInitAndConstructorCode(ContractDefinition const& _contract);
+	void appendBaseConstructor(FunctionDefinition const& _constructor);
+	void appendConstructor(FunctionDefinition const& _constructor);
+	void appendFunctionSelector(ContractDefinition const& _contract);
+	/// Creates code that unpacks the arguments for the given function represented by a vector of TypePointers.
+	/// From memory if @a _fromMemory is true, otherwise from call data.
+	/// Expects source offset on the stack, which is removed.
+	void appendCalldataUnpacker(TypePointers const& _typeParameters, bool _fromMemory = false);
+	void appendReturnValuePacker(TypePointers const& _typeParameters, bool _isLibrary);
+
+	void registerStateVariables(ContractDefinition const& _contract);
+	void initializeStateVariables(ContractDefinition const& _contract);
+
+	virtual bool visit(VariableDeclaration const& _variableDeclaration) override;
+	virtual bool visit(FunctionDefinition const& _function) override;
+	virtual bool visit(InlineAssembly const& _inlineAssembly) override;
+	virtual bool visit(IfStatement const& _ifStatement) override;
+	virtual bool visit(WhileStatement const& _whileStatement) override;
+	virtual bool visit(ForStatement const& _forStatement) override;
+	virtual bool visit(Continue const& _continue) override;
+	virtual bool visit(Break const& _break) override;
+	virtual bool visit(Return const& _return) override;
+	virtual bool visit(Throw const& _throw) override;
+	virtual bool visit(VariableDeclarationStatement const& _variableDeclarationStatement) override;
+	virtual bool visit(ExpressionStatement const& _expressionStatement) override;
+	virtual bool visit(PlaceholderStatement const&) override;
+
+	/// Repeatedly visits all function which are referenced but which are not compiled yet.
+	void appendMissingFunctions();
+
+	/// Appends one layer of function modifier code of the current function, or the function
+	/// body itself if the last modifier was reached.
+	void appendModifierOrFunctionCode();
+
+	void appendStackVariableInitialisation(VariableDeclaration const& _variable);
+	void compileExpression(Expression const& _expression, TypePointer const& _targetType = TypePointer());
+
+	/// @returns the runtime assembly for clone contracts.
+	static eth::Assembly cloneRuntime();
+
+	bool const m_optimise;
+	CompilerContext& m_context;
+	std::vector<eth::AssemblyItem> m_breakTags; ///< tag to jump to for a "break" statement
+	std::vector<eth::AssemblyItem> m_continueTags; ///< tag to jump to for a "continue" statement
+	eth::AssemblyItem m_returnTag; ///< tag to jump to for a "return" statement
+	unsigned m_modifierDepth = 0;
+	FunctionDefinition const* m_currentFunction = nullptr;
+	unsigned m_stackCleanupForReturn = 0; ///< this number of stack elements need to be removed before jump to m_returnTag
+	// arguments for base constructors, filled in derived-to-base order
+	std::map<FunctionDefinition const*, std::vector<ASTPointer<Expression>> const*> m_baseArguments;
+};
+
+}
+}