PoC-7: JUMPDEST implemented.

libevm/VM.cpp

@@ -29,4 +29,6 @@ void VM::reset(u256 _gas)
 {
 	m_gas = _gas;
 	m_curPC = 0;
+	m_jumpLatch = false;
+	m_destinations.clear();
 }

libevm/VM.h

@@ -39,6 +39,7 @@ struct VMException: virtual Exception {};
 struct StepsDone: virtual VMException {};
 struct BreakPointHit: virtual VMException {};
 struct BadInstruction: virtual VMException {};
+struct BadJumpDestination: virtual VMException {};
 struct OutOfGas: virtual VMException {};
 class StackTooSmall: public VMException { public: StackTooSmall(u256 _req, u256 _got): req(_req), got(_got) {} u256 req; u256 got; };
 
@@ -83,6 +84,8 @@ private:
 	u256 m_curPC = 0;
 	bytes m_temp;
 	u256s m_stack;
+	bool m_jumpLatch = false;
+	u256Set m_destinations;
 };
 
 }
@@ -565,11 +568,17 @@ template <class Ext> dev::bytesConstRef dev::eth::VM::go(Ext& _ext, OnOpFunc con
 			break;
 		case Instruction::JUMP:
 			require(1);
+			m_jumpLatch = true;
+			if (!m_destinations.count(m_stack.back()))
+				BOOST_THROW_EXCEPTION(BadJumpDestination());
 			nextPC = m_stack.back();
 			m_stack.pop_back();
 			break;
 		case Instruction::JUMPI:
 			require(2);
+			m_jumpLatch = true;
+			if (!m_destinations.count(m_stack.back()))
+				BOOST_THROW_EXCEPTION(BadJumpDestination());
 			if (m_stack[m_stack.size() - 2])
 				nextPC = m_stack.back();
 			m_stack.pop_back();
@@ -584,6 +593,12 @@ template <class Ext> dev::bytesConstRef dev::eth::VM::go(Ext& _ext, OnOpFunc con
 		case Instruction::GAS:
 			m_stack.push_back(m_gas);
 			break;
+		case Instruction::JUMPDEST:
+			require(1);
+			if (!m_jumpLatch)
+				m_destinations.insert(m_stack.back());
+			m_stack.pop_back();
+			break;
 		case Instruction::CREATE:
 		{
 			require(3);

libevmface/Instruction.cpp

@@ -82,6 +82,7 @@ const std::map<std::string, Instruction> dev::eth::c_instructions =
 	{ "PC", Instruction::PC },
 	{ "MSIZE", Instruction::MSIZE },
 	{ "GAS", Instruction::GAS },
+	{ "JUMPDEST", Instruction::JUMPDEST },
 	{ "PUSH1", Instruction::PUSH1 },
 	{ "PUSH2", Instruction::PUSH2 },
 	{ "PUSH3", Instruction::PUSH3 },
@@ -208,6 +209,7 @@ static const std::map<Instruction, InstructionInfo> c_instructionInfo =
 	{ Instruction::PC,			{ "PC",				0, 0, 1 } },
 	{ Instruction::MSIZE,		{ "MSIZE",			0, 0, 1 } },
 	{ Instruction::GAS,			{ "GAS",			0, 0, 1 } },
+	{ Instruction::JUMPDEST,	{ "JUMPDEST",		0, 1, 0 } },
 	{ Instruction::PUSH1,		{ "PUSH1",			1, 0, 1 } },
 	{ Instruction::PUSH2,		{ "PUSH2",			2, 0, 1 } },
 	{ Instruction::PUSH3,		{ "PUSH3",			3, 0, 1 } },
@@ -274,7 +276,7 @@ static const std::map<Instruction, InstructionInfo> c_instructionInfo =
 	{ Instruction::SWAP16,		{ "SWAP16",			0, 17, 17 } },
 	{ Instruction::CREATE,		{ "CREATE",			0, 3, 1 } },
 	{ Instruction::CALL,		{ "CALL",			0, 7, 1 } },
-	{ Instruction::CALLCODE, { "CALLCODE",0, 7, 1 } },
+	{ Instruction::CALLCODE,	{ "CALLCODE",		0, 7, 1 } },
 	{ Instruction::RETURN,		{ "RETURN",			0, 2, 0 } },
 	{ Instruction::SUICIDE,		{ "SUICIDE",		0, 1, 0} }
 };

libevmface/Instruction.h

@@ -92,6 +92,7 @@ enum class Instruction: uint8_t
 	PC,					///< get the program counter
 	MSIZE,				///< get the size of active memory
 	GAS,				///< get the amount of available gas
+	JUMPDEST,			///< set a potential jump destination
 
 	PUSH1 = 0x60,		///< place 1 byte item on stack
 	PUSH2,				///< place 2 byte item on stack

liblll/Assembly.cpp

@@ -149,6 +149,17 @@ ostream& dev::eth::operator<<(ostream& _out, AssemblyItemsConstRef _i)
 
 ostream& Assembly::streamOut(ostream& _out, string const& _prefix) const
 {
+	_out << _prefix << ".pre:" << endl;
+	for (AssemblyItem const& i: m_items)
+		switch (i.m_type)
+		{
+		case PushTag:
+			_out << _prefix << "  PUSH [tag" << i.m_data << "]" << endl;
+			_out << _prefix << "  JUMPDEST" << endl;
+			break;
+		default:;
+		}
+
 	_out << _prefix << ".code:" << endl;
 	for (AssemblyItem const& i: m_items)
 		switch (i.m_type)
@@ -353,9 +364,11 @@ bytes Assembly::assemble() const
 	ret.reserve(totalBytes);
 	vector<unsigned> tagPos(m_usedTags);
 	map<unsigned, unsigned> tagRef;
+	map<unsigned, unsigned> pretagRef;
 	multimap<h256, unsigned> dataRef;
 	unsigned bytesPerTag = dev::bytesRequired(totalBytes);
 	byte tagPush = (byte)Instruction::PUSH1 - 1 + bytesPerTag;
+	bytes preret;
 
 	for (auto const& i: m_subs)
 		m_data[i.first] = i.second.assemble();
@@ -393,6 +406,11 @@ bytes Assembly::assemble() const
 			ret.push_back(tagPush);
 			tagRef[ret.size()] = (unsigned)i.m_data;
 			ret.resize(ret.size() + bytesPerTag);
+
+			preret.push_back(tagPush);
+			pretagRef[preret.size()] = (unsigned)i.m_data;
+			preret.resize(preret.size() + bytesPerTag);
+			preret.push_back((byte)Instruction::JUMPDEST);
 			break;
 		}
 		case PushData: case PushSub:
@@ -424,6 +442,12 @@ bytes Assembly::assemble() const
 		toBigEndian(tagPos[i.second], r);
 	}
 
+	for (auto const& i: pretagRef)
+	{
+		bytesRef r(preret.data() + i.first, bytesPerTag);
+		toBigEndian(tagPos[i.second], r);
+	}
+
 	if (m_data.size())
 	{
 		ret.push_back(0);
@@ -442,5 +466,5 @@ bytes Assembly::assemble() const
 			}
 		}
 	}
-	return ret;
+	return preret + ret;
 }