Initial EVM1.5 assembly implementation.

1 files changed, 174 insertions, 0 deletions

diff --git a/libjulia/backends/evm/EVMAssembly.cpp b/libjulia/backends/evm/EVMAssembly.cpp
new file mode 100644
index 00000000..a8019e86
--- /dev/null
+++ b/libjulia/backends/evm/EVMAssembly.cpp
@@ -0,0 +1,174 @@
+/*
+	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/>.
+*/
+/**
+ * Assembly interface for EVM and EVM1.5.
+ */
+
+#include <libjulia/backends/evm/EVMAssembly.h>
+
+#include <libevmasm/Instruction.h>
+
+#include <libsolidity/interface/Utils.h>
+
+using namespace std;
+using namespace dev;
+using namespace julia;
+
+namespace
+{
+size_t constexpr labelReferenceSize = 4;
+}
+
+
+void EVMAssembly::setSourceLocation(SourceLocation const&)
+{
+	// Ignored for now;
+}
+
+void EVMAssembly::appendInstruction(solidity::Instruction _instr)
+{
+	m_bytecode.push_back(byte(_instr));
+	m_stackHeight += solidity::instructionInfo(_instr).ret - solidity::instructionInfo(_instr).args;
+}
+
+void EVMAssembly::appendConstant(u256 const& _constant)
+{
+	bytes data = toCompactBigEndian(_constant, 1);
+	appendInstruction(solidity::pushInstruction(data.size()));
+	m_bytecode += data;
+}
+
+void EVMAssembly::appendLabel(LabelID _labelId)
+{
+	setLabelToCurrentPosition(_labelId);
+	appendInstruction(solidity::Instruction::JUMPDEST);
+}
+
+void EVMAssembly::appendLabelReference(LabelID _labelId)
+{
+	solAssert(!m_evm15, "Cannot use plain label references in EMV1.5 mode.");
+	// @TODO we now always use labelReferenceSize for all labels, it could be shortened
+	// for some of them.
+	appendInstruction(solidity::pushInstruction(labelReferenceSize));
+	m_labelReferences[m_bytecode.size()] = _labelId;
+	m_bytecode += bytes(labelReferenceSize);
+}
+
+EVMAssembly::LabelID EVMAssembly::newLabelId()
+{
+	m_labelPositions[m_nextLabelID] = size_t(-1);
+	return m_nextLabelID++;
+}
+
+void EVMAssembly::appendLinkerSymbol(string const&)
+{
+	solAssert(false, "Linker symbols not yet implemented.");
+}
+
+void EVMAssembly::appendJump(int _stackDiffAfter)
+{
+	solAssert(!m_evm15, "Plain JUMP used for EVM 1.5");
+	appendInstruction(solidity::Instruction::JUMP);
+	m_stackHeight += _stackDiffAfter;
+}
+
+void EVMAssembly::appendJumpTo(AbstractAssembly::LabelID _labelId, int _stackDiffAfter)
+{
+	if (m_evm15)
+	{
+		m_bytecode.push_back(byte(solidity::Instruction::JUMPTO));
+		appendLabelReferenceInternal(_labelId);
+		m_stackHeight += _stackDiffAfter;
+	}
+	else
+	{
+		appendLabelReference(_labelId);
+		appendJump(_stackDiffAfter);
+	}
+}
+
+void EVMAssembly::appendJumpToIf(AbstractAssembly::LabelID _labelId)
+{
+	if (m_evm15)
+	{
+		m_bytecode.push_back(byte(solidity::Instruction::JUMPIF));
+		appendLabelReferenceInternal(_labelId);
+		m_stackHeight--;
+	}
+	else
+	{
+		appendLabelReference(_labelId);
+		appendInstruction(solidity::Instruction::JUMPI);
+	}
+}
+
+void EVMAssembly::appendBeginsub(AbstractAssembly::LabelID _labelId, int _arguments)
+{
+	solAssert(m_evm15, "BEGINSUB used for EVM 1.0");
+	solAssert(_arguments >= 0, "");
+	setLabelToCurrentPosition(_labelId);
+	m_bytecode.push_back(byte(solidity::Instruction::BEGINSUB));
+	m_stackHeight += _arguments;
+}
+
+void EVMAssembly::appendJumpsub(AbstractAssembly::LabelID _labelId, int _arguments, int _returns)
+{
+	solAssert(m_evm15, "JUMPSUB used for EVM 1.0");
+	solAssert(_arguments >= 0 && _returns >= 0, "");
+	m_bytecode.push_back(byte(solidity::Instruction::JUMPSUB));
+	appendLabelReferenceInternal(_labelId);
+	m_stackHeight += _returns - _arguments;
+}
+
+void EVMAssembly::appendReturnsub(int _returns)
+{
+	solAssert(m_evm15, "RETURNSUB used for EVM 1.0");
+	solAssert(_returns >= 0, "");
+	m_bytecode.push_back(byte(solidity::Instruction::RETURNSUB));
+	m_stackHeight -= _returns;
+}
+
+eth::LinkerObject EVMAssembly::finalize()
+{
+	for (auto const& ref: m_labelReferences)
+	{
+		size_t referencePos = ref.first;
+		solAssert(m_labelPositions.count(ref.second), "");
+		size_t labelPos = m_labelPositions.at(ref.second);
+		solAssert(labelPos != size_t(-1), "Undefined but allocated label used.");
+		solAssert(m_bytecode.size() >= 4 && referencePos <= m_bytecode.size() - 4, "");
+		solAssert(labelPos < (uint64_t(1) << (8 * labelReferenceSize)), "");
+		for (size_t i = 0; i < labelReferenceSize; i++)
+			m_bytecode[referencePos + i] = byte((labelPos >> (8 * (labelReferenceSize - i - 1))) & 0xff);
+	}
+	eth::LinkerObject obj;
+	obj.bytecode = m_bytecode;
+	return obj;
+}
+
+void EVMAssembly::setLabelToCurrentPosition(AbstractAssembly::LabelID _labelId)
+{
+	solAssert(m_labelPositions.count(_labelId), "Label not found.");
+	solAssert(m_labelPositions[_labelId] == size_t(-1), "Label already set.");
+	m_labelPositions[_labelId] = m_bytecode.size();
+}
+
+void EVMAssembly::appendLabelReferenceInternal(AbstractAssembly::LabelID _labelId)
+{
+	m_labelReferences[m_bytecode.size()] = _labelId;
+	m_bytecode += bytes(labelReferenceSize);
+}