Merge branch 'develop-evmcc' of github.com:imapp-pl/ethereum into develop-evmcc

evmcc/Compiler.cpp

@@ -609,6 +609,7 @@ std::unique_ptr<llvm::Module> Compiler::compile(const dev::bytes& bytecode)
 			{
 				auto index = stack.pop();
 				auto value = stack.pop();
+				gasMeter.countSStore(ext, index, value);
 				ext.setStore(index, value);
 				break;
 			}
@@ -689,8 +690,7 @@ std::unique_ptr<llvm::Module> Compiler::compile(const dev::bytes& bytecode)
 
 			case Instruction::GAS:
 			{
-				auto value = builder.CreateLoad(gasMeter.getLLVMGasVar());
+				stack.push(gasMeter.getGas());
-				stack.push(value);
 				break;
 			}
 

evmcc/ExecutionEngine.cpp

@@ -13,6 +13,8 @@
 #include <llvm/Support/PrettyStackTrace.h>
 #include <llvm/Support/Host.h>
 
+#include <libevm/VM.h>
+
 #include "Runtime.h"
 #include "Memory.h"
 #include "Type.h"
@@ -89,7 +91,7 @@ int ExecutionEngine::run(std::unique_ptr<llvm::Module> _module)
 	ext->code = decltype(ext->code)(fakecode, 8);
 
 	// Init runtime
-	uint64_t gas = 1000000;
+	uint64_t gas = 100;
 	Runtime runtime(gas, std::move(ext));
 
 	auto entryFunc = module->getFunction("main");
@@ -99,9 +101,20 @@ int ExecutionEngine::run(std::unique_ptr<llvm::Module> _module)
 		exit(1);
 	}
 
-	auto result = exec->runFunction(entryFunc, {});
+
+	ReturnCode returnCode;
+	try
+	{
+		auto result = exec->runFunction(entryFunc, {});
+		returnCode = static_cast<ReturnCode>(result.IntVal.getZExtValue());
+	}
+	catch (const dev::eth::OutOfGas&)
+	{
+		returnCode = ReturnCode::OutOfGas;
+	}
+
 	gas = static_cast<decltype(gas)>(Runtime::getGas());
-	auto returnCode = static_cast<ReturnCode>(result.IntVal.getZExtValue());
+	
 	if (returnCode == ReturnCode::Return)
 	{
 		auto&& returnData = Memory::getReturnData(); // TODO: It might be better to place is in Runtime interface
@@ -110,10 +123,8 @@ int ExecutionEngine::run(std::unique_ptr<llvm::Module> _module)
 		for (auto it = returnData.begin(), end = returnData.end(); it != end; ++it)
 			std::cout << std::hex << std::setw(2) << std::setfill('0') << (int)*it << " ";
 		std::cout << "]\n";
-
-		return 10;
 	}	
-	return 0;
+	return static_cast<int>(returnCode);
 }
 
 }

evmcc/GasMeter.cpp

@@ -9,6 +9,7 @@
 
 #include "Type.h"
 #include "Utils.h"
+#include "Ext.h"
 
 namespace evmcc
 {
@@ -82,11 +83,27 @@ GasMeter::GasMeter(llvm::IRBuilder<>& _builder, llvm::Module* _module):
 	m_gas = new llvm::GlobalVariable(*_module, Type::i256, false, llvm::GlobalVariable::ExternalLinkage, nullptr, "gas");
 	m_gas->setUnnamedAddr(true); // Address is not important
 
+	m_rtExit = llvm::Function::Create(llvm::FunctionType::get(Type::Void, Type::MainReturn, false), llvm::Function::ExternalLinkage, "rt_exit", _module);
+
 	m_gasCheckFunc = llvm::Function::Create(llvm::FunctionType::get(Type::Void, Type::i256, false), llvm::Function::PrivateLinkage, "gas.check", _module);
 	InsertPointGuard guard(m_builder); 
-	m_builder.SetInsertPoint(llvm::BasicBlock::Create(_builder.getContext(), {}, m_gasCheckFunc));
+
+	auto checkBB = llvm::BasicBlock::Create(_builder.getContext(), "check", m_gasCheckFunc);
+	auto outOfGasBB = llvm::BasicBlock::Create(_builder.getContext(), "outOfGas", m_gasCheckFunc);
+	auto updateBB = llvm::BasicBlock::Create(_builder.getContext(), "update", m_gasCheckFunc);
+
+	m_builder.SetInsertPoint(checkBB);
 	llvm::Value* cost = m_gasCheckFunc->arg_begin();
-	llvm::Value* gas = m_builder.CreateLoad(m_gas);
+	cost->setName("cost");
+	llvm::Value* gas = m_builder.CreateLoad(m_gas, "gas");
+	auto isOutOfGas = m_builder.CreateICmpUGT(cost, gas, "isOutOfGas");
+	m_builder.CreateCondBr(isOutOfGas, outOfGasBB, updateBB);
+
+	m_builder.SetInsertPoint(outOfGasBB);
+	m_builder.CreateCall(m_rtExit, Constant::get(ReturnCode::OutOfGas));
+	m_builder.CreateRetVoid();
+
+	m_builder.SetInsertPoint(updateBB);
 	gas = m_builder.CreateSub(gas, cost);
 	m_builder.CreateStore(gas, m_gas);
 	m_builder.CreateRetVoid();
@@ -100,12 +117,34 @@ void GasMeter::count(Instruction _inst)
 		m_checkCall = m_builder.CreateCall(m_gasCheckFunc, llvm::UndefValue::get(Type::i256));
 	}
 	
-	m_blockCost += getStepCost(_inst);
+	if (_inst != Instruction::SSTORE) // Handle cost of SSTORE separately in countSStore()
+		m_blockCost += getStepCost(_inst);
 
 	if (isCostBlockEnd(_inst))
 		commitCostBlock();
 }
 
+void GasMeter::countSStore(Ext& _ext, llvm::Value* _index, llvm::Value* _newValue)
+{
+	assert(!m_checkCall); // Everything should've been commited before
+
+	static const auto sstoreCost = static_cast<uint64_t>(c_sstoreGas);
+
+	// [ADD] if oldValue == 0 and newValue != 0  =>  2*cost
+	// [DEL] if oldValue != 0 and newValue == 0  =>  0
+
+	auto oldValue = _ext.store(_index);
+	auto oldValueIsZero = m_builder.CreateICmpEQ(oldValue, Constant::get(0), "oldValueIsZero");
+	auto newValueIsZero = m_builder.CreateICmpEQ(_newValue, Constant::get(0), "newValueIsZero");
+	auto oldValueIsntZero = m_builder.CreateICmpNE(oldValue, Constant::get(0), "oldValueIsntZero");
+	auto newValueIsntZero = m_builder.CreateICmpNE(_newValue, Constant::get(0), "newValueIsntZero");
+	auto isAdd = m_builder.CreateAnd(oldValueIsZero, newValueIsntZero, "isAdd");
+	auto isDel = m_builder.CreateAnd(oldValueIsntZero, newValueIsZero, "isDel");
+	auto cost = m_builder.CreateSelect(isAdd, Constant::get(2 * sstoreCost), Constant::get(sstoreCost), "cost");
+	cost = m_builder.CreateSelect(isDel, Constant::get(0), cost, "cost");
+	m_builder.CreateCall(m_gasCheckFunc, cost);
+}
+
 void GasMeter::giveBack(llvm::Value* _gas)
 {
 	llvm::Value* gasCounter = m_builder.CreateLoad(m_gas, "gas");
@@ -144,9 +183,9 @@ void GasMeter::checkMemory(llvm::Value* _additionalMemoryInWords, llvm::IRBuilde
 	_builder.CreateCall(m_gasCheckFunc, cost);
 }
 
-llvm::GlobalVariable* GasMeter::getLLVMGasVar()
+llvm::Value* GasMeter::getGas()
 {
-	return m_gas;
+	return m_builder.CreateLoad(m_gas, "gas");
 }
 
 }

evmcc/GasMeter.h

@@ -19,6 +19,9 @@ public:
 	/// Count step cost of instruction
 	void count(dev::eth::Instruction _inst);
 
+	/// Calculate & count gas cost for SSTORE instruction
+	void countSStore(class Ext& _ext, llvm::Value* _index, llvm::Value* _newValue);
+
 	/// Finalize cost-block by checking gas needed for the block before the block
 	/// @param _additionalCost adds additional cost to cost-block before commit
 	void commitCostBlock(llvm::Value* _additionalCost = nullptr);
@@ -29,7 +32,7 @@ public:
 	/// Generate code that checks the cost of additional memory used by program
 	void checkMemory(llvm::Value* _additionalMemoryInWords, llvm::IRBuilder<>& _builder);
 
-	llvm::GlobalVariable* getLLVMGasVar();
+	llvm::Value* getGas();
 
 private:
 	/// Cumulative gas cost of a block of instructions
@@ -38,6 +41,7 @@ private:
 	llvm::IRBuilder<>& m_builder;
 	llvm::CallInst* m_checkCall = nullptr;
 	llvm::GlobalVariable* m_gas;
+	llvm::Function* m_rtExit;
 	llvm::Function* m_gasCheckFunc;
 };
 

evmcc/Memory.cpp

@@ -40,6 +40,10 @@ Memory::Memory(llvm::IRBuilder<>& _builder, llvm::Module* _module, GasMeter& _ga
 	m_returnDataSize->setUnnamedAddr(true); // Address is not important
 
 	m_resize = llvm::Function::Create(llvm::FunctionType::get(Type::BytePtr, Type::WordPtr, false), llvm::Function::ExternalLinkage, "mem_resize", _module);
+	llvm::AttrBuilder attrBuilder;
+	attrBuilder.addAttribute(llvm::Attribute::NoAlias).addAttribute(llvm::Attribute::NoCapture).addAttribute(llvm::Attribute::NonNull).addAttribute(llvm::Attribute::ReadOnly);
+	m_resize->setAttributes(llvm::AttributeSet::get(m_resize->getContext(), 1, attrBuilder));
+
 	m_require = createRequireFunc(_module, _gasMeter);
 	m_loadWord = createFunc(false, Type::i256, _module, _gasMeter);
 	m_storeWord = createFunc(true, Type::i256, _module, _gasMeter);

evmcc/Runtime.cpp

@@ -1,12 +1,27 @@
 
 #include "Runtime.h"
 
+#include <libevm/VM.h>
+
+#include "Type.h"
+
 namespace evmcc
 {
 
 static Runtime* g_runtime;
 
-extern "C" { EXPORT i256 gas; }
+extern "C"
+{
+EXPORT i256 gas;
+
+EXPORT void rt_exit(int32_t _returnCode)
+{
+	auto returnCode = static_cast<ReturnCode>(_returnCode);
+	if (returnCode == ReturnCode::OutOfGas)
+		BOOST_THROW_EXCEPTION(dev::eth::OutOfGas());
+}
+
+}
 
 Runtime::Runtime(dev::u256 _gas, std::unique_ptr<dev::eth::ExtVMFace> _ext):
 	m_ext(std::move(_ext))

evmcc/Type.h

@@ -34,6 +34,7 @@ enum class ReturnCode
 	Suicide = 2,
 
 	BadJumpDestination = 101,
+	OutOfGas = 102,
 };
 
 struct Constant