Contract compiler and also add ExpressionStatement to AST.

ExpressionStatement functions as glue between Statements and Expressions.

This way it is possible to detect when the border between statements and
expressions is crossed while walking the AST. Note that ExpressionStatement is
not the only border, almost every statement can contains expressions.

1 files changed, 348 insertions, 0 deletions

diff --git a/solidityExpressionCompiler.cpp b/solidityExpressionCompiler.cpp
new file mode 100644
index 00000000..2a58d670
--- /dev/null
+++ b/solidityExpressionCompiler.cpp
@@ -0,0 +1,348 @@
+
+/*
+	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
+ * Unit tests for the solidity expression compiler.
+ */
+
+#include <string>
+
+#include <libdevcore/Log.h>
+#include <libsolidity/Scanner.h>
+#include <libsolidity/Parser.h>
+#include <libsolidity/NameAndTypeResolver.h>
+#include <libsolidity/ExpressionCompiler.h>
+#include <libsolidity/AST.h>
+#include <boost/test/unit_test.hpp>
+
+using namespace std;
+
+namespace dev
+{
+namespace solidity
+{
+namespace test
+{
+
+namespace
+{
+
+/// Helper class that extracts the first expression in an AST.
+class FirstExpressionExtractor: private ASTVisitor
+{
+public:
+	FirstExpressionExtractor(ASTNode& _node): m_expression(nullptr) { _node.accept(*this); }
+	Expression* getExpression() const { return m_expression; }
+private:
+	virtual bool visit(Expression& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(Assignment& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(UnaryOperation& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(BinaryOperation& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(FunctionCall& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(MemberAccess& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(IndexAccess& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(PrimaryExpression& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(Identifier& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(ElementaryTypeNameExpression& _expression) override { return checkExpression(_expression); }
+	virtual bool visit(Literal& _expression) override { return checkExpression(_expression); }
+	bool checkExpression(Expression& _expression)
+	{
+		if (m_expression == nullptr)
+			m_expression = &_expression;
+		return false;
+	}
+private:
+	Expression* m_expression;
+};
+
+Declaration const& resolveDeclaration(vector<string> const& _namespacedName,
+											  NameAndTypeResolver const& _resolver)
+{
+	Declaration const* declaration = nullptr;
+	for (string const& namePart: _namespacedName)
+		BOOST_REQUIRE(declaration = _resolver.resolveName(namePart, declaration));
+	BOOST_REQUIRE(declaration);
+	return *declaration;
+}
+
+bytes compileFirstExpression(const string& _sourceCode, vector<vector<string>> _functions = {},
+							 vector<vector<string>> _localVariables = {})
+{
+	Parser parser;
+	ASTPointer<ContractDefinition> contract;
+	BOOST_REQUIRE_NO_THROW(contract = parser.parse(make_shared<Scanner>(CharStream(_sourceCode))));
+	NameAndTypeResolver resolver;
+	BOOST_REQUIRE_NO_THROW(resolver.resolveNamesAndTypes(*contract));
+	FirstExpressionExtractor extractor(*contract);
+	BOOST_REQUIRE(extractor.getExpression() != nullptr);
+
+	CompilerContext context;
+	for (vector<string> const& function: _functions)
+		context.addFunction(dynamic_cast<FunctionDefinition const&>(resolveDeclaration(function, resolver)));
+	for (vector<string> const& variable: _localVariables)
+		context.addVariable(dynamic_cast<VariableDeclaration const&>(resolveDeclaration(variable, resolver)));
+
+	ExpressionCompiler::compileExpression(context, *extractor.getExpression());
+
+	for (vector<string> const& function: _functions)
+		context << context.getFunctionEntryLabel(dynamic_cast<FunctionDefinition const&>(resolveDeclaration(function, resolver)));
+	bytes instructions = context.getAssembledBytecode();
+	// debug
+	// cout << eth::disassemble(instructions) << endl;
+	return instructions;
+}
+
+} // end anonymous namespace
+
+BOOST_AUTO_TEST_SUITE(SolidityExpressionCompiler)
+
+BOOST_AUTO_TEST_CASE(literal_true)
+{
+	char const* sourceCode = "contract test {\n"
+							 "  function f() { var x = true; }"
+							 "}\n";
+	bytes code = compileFirstExpression(sourceCode);
+
+	bytes expectation({byte(eth::Instruction::PUSH1), 0x1});
+	BOOST_CHECK_EQUAL_COLLECTIONS(code.begin(), code.end(), expectation.begin(), expectation.end());
+}
+
+BOOST_AUTO_TEST_CASE(literal_false)
+{
+	char const* sourceCode = "contract test {\n"
+							 "  function f() { var x = false; }"
+							 "}\n";
+	bytes code = compileFirstExpression(sourceCode);
+
+	bytes expectation({byte(eth::Instruction::PUSH1), 0x0});
+	BOOST_CHECK_EQUAL_COLLECTIONS(code.begin(), code.end(), expectation.begin(), expectation.end());
+}
+
+BOOST_AUTO_TEST_CASE(int_literal)
+{
+	char const* sourceCode = "contract test {\n"
+							 "  function f() { var x = 0x12345678901234567890; }"
+							 "}\n";
+	bytes code = compileFirstExpression(sourceCode);
+
+	bytes expectation({byte(eth::Instruction::PUSH10), 0x12, 0x34, 0x56, 0x78, 0x90,
+													   0x12, 0x34, 0x56, 0x78, 0x90});
+	BOOST_CHECK_EQUAL_COLLECTIONS(code.begin(), code.end(), expectation.begin(), expectation.end());
+}
+
+BOOST_AUTO_TEST_CASE(comparison)
+{
+	char const* sourceCode = "contract test {\n"
+							 "  function f() { var x = (0x10aa < 0x11aa) != true; }"
+							 "}\n";
+	bytes code = compileFirstExpression(sourceCode);
+
+	bytes expectation({byte(eth::Instruction::PUSH2), 0x10, 0xaa,
+					   byte(eth::Instruction::PUSH2), 0x11, 0xaa,
+					   byte(eth::Instruction::GT),
+					   byte(eth::Instruction::PUSH1), 0x1,
+					   byte(eth::Instruction::EQ),
+					   byte(eth::Instruction::NOT)});
+	BOOST_CHECK_EQUAL_COLLECTIONS(code.begin(), code.end(), expectation.begin(), expectation.end());
+}
+
+BOOST_AUTO_TEST_CASE(short_circuiting)
+{
+	char const* sourceCode = "contract test {\n"
+							 "  function f() { var x = (10 + 8 >= 4 || 2 != 9) != true; }"
+							 "}\n";
+	bytes code = compileFirstExpression(sourceCode);
+
+	bytes expectation({byte(eth::Instruction::PUSH1), 0xa,
+					   byte(eth::Instruction::PUSH1), 0x8,
+					   byte(eth::Instruction::ADD),
+					   byte(eth::Instruction::PUSH1), 0x4,
+					   byte(eth::Instruction::GT),
+					   byte(eth::Instruction::NOT), // after this we have 10 + 8 >= 4
+					   byte(eth::Instruction::DUP1),
+					   byte(eth::Instruction::PUSH1), 0x14,
+					   byte(eth::Instruction::JUMPI), // short-circuit if it is true
+					   byte(eth::Instruction::PUSH1), 0x2,
+					   byte(eth::Instruction::PUSH1), 0x9,
+					   byte(eth::Instruction::EQ),
+					   byte(eth::Instruction::NOT), // after this we have 2 != 9
+					   byte(eth::Instruction::JUMPDEST),
+					   byte(eth::Instruction::PUSH1), 0x1,
+					   byte(eth::Instruction::EQ),
+					   byte(eth::Instruction::NOT)});
+	BOOST_CHECK_EQUAL_COLLECTIONS(code.begin(), code.end(), expectation.begin(), expectation.end());
+}
+
+BOOST_AUTO_TEST_CASE(arithmetics)
+{
+	char const* sourceCode = "contract test {\n"
+							 "  function f() { var x = (1 * (2 / (3 % (4 + (5 - (6 | (7 & (8 ^ 9)))))))); }"
+							 "}\n";
+	bytes code = compileFirstExpression(sourceCode);
+
+	bytes expectation({byte(eth::Instruction::PUSH1), 0x1,
+					   byte(eth::Instruction::PUSH1), 0x2,
+					   byte(eth::Instruction::PUSH1), 0x3,
+					   byte(eth::Instruction::PUSH1), 0x4,
+					   byte(eth::Instruction::PUSH1), 0x5,
+					   byte(eth::Instruction::PUSH1), 0x6,
+					   byte(eth::Instruction::PUSH1), 0x7,
+					   byte(eth::Instruction::PUSH1), 0x8,
+					   byte(eth::Instruction::PUSH1), 0x9,
+					   byte(eth::Instruction::XOR),
+					   byte(eth::Instruction::AND),
+					   byte(eth::Instruction::OR),
+					   byte(eth::Instruction::SWAP1),
+					   byte(eth::Instruction::SUB),
+					   byte(eth::Instruction::ADD),
+					   byte(eth::Instruction::MOD),
+					   byte(eth::Instruction::DIV),
+					   byte(eth::Instruction::MUL)});
+	BOOST_CHECK_EQUAL_COLLECTIONS(code.begin(), code.end(), expectation.begin(), expectation.end());
+}
+
+BOOST_AUTO_TEST_CASE(unary_operators)
+{
+	char const* sourceCode = "contract test {\n"
+							 "  function f() { var x = !(~+-1 == 2); }"
+							 "}\n";
+	bytes code = compileFirstExpression(sourceCode);
+
+	bytes expectation({byte(eth::Instruction::PUSH1), 0x1,
+					   byte(eth::Instruction::PUSH1), 0x0,
+					   byte(eth::Instruction::SUB),
+					   byte(eth::Instruction::BNOT),
+					   byte(eth::Instruction::PUSH1), 0x2,
+					   byte(eth::Instruction::EQ),
+					   byte(eth::Instruction::NOT)});
+	BOOST_CHECK_EQUAL_COLLECTIONS(code.begin(), code.end(), expectation.begin(), expectation.end());
+}
+
+BOOST_AUTO_TEST_CASE(unary_inc_dec)
+{
+	char const* sourceCode = "contract test {\n"
+							 "  function f(uint a) { var x = ((a++ ^ ++a) ^ a--) ^ --a; }"
+							 "}\n";
+	bytes code = compileFirstExpression(sourceCode, {}, {{"test", "f", "a"}, {"test", "f", "x"}});
+
+	// Stack: a, x
+	bytes expectation({byte(eth::Instruction::DUP2),
+					   byte(eth::Instruction::DUP1),
+					   byte(eth::Instruction::PUSH1), 0x1,
+					   byte(eth::Instruction::ADD),
+					   // Stack here: a x a (a+1)
+					   byte(eth::Instruction::SWAP3),
+					   byte(eth::Instruction::POP), // first ++
+					   // Stack here: (a+1) x a
+					   byte(eth::Instruction::DUP3),
+					   byte(eth::Instruction::PUSH1), 0x1,
+					   byte(eth::Instruction::ADD),
+					   // Stack here: (a+1) x a (a+2)
+					   byte(eth::Instruction::SWAP3),
+					   byte(eth::Instruction::POP),
+					   // Stack here: (a+2) x a
+					   byte(eth::Instruction::DUP3), // second ++
+					   byte(eth::Instruction::XOR),
+					   // Stack here: (a+2) x a^(a+2)
+					   byte(eth::Instruction::DUP3),
+					   byte(eth::Instruction::DUP1),
+					   byte(eth::Instruction::PUSH1), 0x1,
+					   byte(eth::Instruction::SWAP1),
+					   byte(eth::Instruction::SUB),
+					   // Stack here: (a+2) x a^(a+2) (a+2) (a+1)
+					   byte(eth::Instruction::SWAP4),
+					   byte(eth::Instruction::POP), // first --
+					   byte(eth::Instruction::XOR),
+					   // Stack here: (a+1) x a^(a+2)^(a+2)
+					   byte(eth::Instruction::DUP3),
+					   byte(eth::Instruction::PUSH1), 0x1,
+					   byte(eth::Instruction::SWAP1),
+					   byte(eth::Instruction::SUB),
+					   // Stack here: (a+1) x a^(a+2)^(a+2) a
+					   byte(eth::Instruction::SWAP3),
+					   byte(eth::Instruction::POP), // second ++
+					   // Stack here: a x a^(a+2)^(a+2)
+					   byte(eth::Instruction::DUP3), // will change
+					   byte(eth::Instruction::XOR)});
+					   // Stack here: a x a^(a+2)^(a+2)^a
+	BOOST_CHECK_EQUAL_COLLECTIONS(code.begin(), code.end(), expectation.begin(), expectation.end());
+}
+
+BOOST_AUTO_TEST_CASE(assignment)
+{
+	char const* sourceCode = "contract test {\n"
+							 "  function f(uint a, uint b) { (a += b) * 2; }"
+							 "}\n";
+	bytes code = compileFirstExpression(sourceCode, {}, {{"test", "f", "a"}, {"test", "f", "b"}});
+
+	// Stack: a, b
+	bytes expectation({byte(eth::Instruction::DUP1),
+					   byte(eth::Instruction::DUP3),
+					   byte(eth::Instruction::SWAP1),
+					   byte(eth::Instruction::ADD),
+					   // Stack here: a b a+b
+					   byte(eth::Instruction::SWAP2),
+					   byte(eth::Instruction::POP),
+					   byte(eth::Instruction::DUP2),
+					   // Stack here: a+b b a+b
+					   byte(eth::Instruction::PUSH1), 0x2,
+					   byte(eth::Instruction::MUL)});
+	BOOST_CHECK_EQUAL_COLLECTIONS(code.begin(), code.end(), expectation.begin(), expectation.end());
+}
+
+BOOST_AUTO_TEST_CASE(function_call)
+{
+	char const* sourceCode = "contract test {\n"
+							 "  function f(uint a, uint b) { a += g(a + 1, b) * 2; }\n"
+							 "  function g(uint a, uint b) returns (uint c) {}\n"
+							 "}\n";
+	bytes code = compileFirstExpression(sourceCode, {{"test", "g"}},
+										{{"test", "f", "a"}, {"test", "f", "b"}});
+
+	// Stack: a, b
+	bytes expectation({byte(eth::Instruction::PUSH1), 0x0b,
+					   byte(eth::Instruction::DUP3),
+					   byte(eth::Instruction::PUSH1), 0x01,
+					   byte(eth::Instruction::ADD),
+					   // Stack here: a b <ret label> (a+1)
+					   byte(eth::Instruction::DUP3),
+					   byte(eth::Instruction::PUSH1), 0x15,
+					   byte(eth::Instruction::JUMP),
+					   byte(eth::Instruction::JUMPDEST),
+					   // Stack here: a b g(a+1, b)
+					   byte(eth::Instruction::PUSH1), 0x02,
+					   byte(eth::Instruction::MUL),
+					   // Stack here: a b g(a+1, b)*2
+					   byte(eth::Instruction::DUP3),
+					   byte(eth::Instruction::SWAP1),
+					   byte(eth::Instruction::ADD),
+					   // Stack here: a b a+g(a+1, b)*2
+					   byte(eth::Instruction::SWAP2),
+					   byte(eth::Instruction::POP),
+					   byte(eth::Instruction::DUP2),
+					   byte(eth::Instruction::JUMPDEST)});
+	BOOST_CHECK_EQUAL_COLLECTIONS(code.begin(), code.end(), expectation.begin(), expectation.end());
+}
+
+BOOST_AUTO_TEST_SUITE_END()
+
+}
+}
+} // end namespaces
+