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

Conflicts:
	evmcc/Compiler.cpp

evmcc/Compiler.cpp

@@ -199,9 +199,9 @@ std::unique_ptr<llvm::Module> Compiler::compile(const dev::bytes& bytecode)
 	createBasicBlocks(bytecode);
 
 	// Init runtime structures.
-	Memory memory(builder, module.get());
-	Ext ext(builder, module.get());
 	GasMeter gasMeter(builder, module.get());
+	Memory memory(builder, module.get(), gasMeter);
+	Ext ext(builder, module.get());
 
 	// Jump to first instruction
 	builder.CreateBr(basicBlocks.begin()->second);
@@ -216,7 +216,7 @@ std::unique_ptr<llvm::Module> Compiler::compile(const dev::bytes& bytecode)
 		{
 			auto inst = static_cast<Instruction>(bytecode[currentPC]);
 
-			gasMeter.check(inst);
+			gasMeter.count(inst);
 
 			switch (inst)
 			{
@@ -820,6 +820,8 @@ std::unique_ptr<llvm::Module> Compiler::compile(const dev::bytes& bytecode)
 			}
 		}
 
+		gasMeter.commitCostBlock();
+
 		if (!builder.GetInsertBlock()->getTerminator())	// If block not terminated
 		{
 			if (basicBlock.end() == bytecode.size())

evmcc/ExecutionEngine.cpp

@@ -85,7 +85,8 @@ int ExecutionEngine::run(std::unique_ptr<llvm::Module> _module)
 	ext->data = calldata;
 
 	// Init runtime
-	Runtime runtime(std::move(ext));
+	uint64_t gas = 1000000;
+	Runtime runtime(gas, std::move(ext));
 
 	auto entryFunc = module->getFunction("main");
 	if (!entryFunc)
@@ -95,6 +96,7 @@ int ExecutionEngine::run(std::unique_ptr<llvm::Module> _module)
 	}
 
 	auto result = exec->runFunction(entryFunc, {});
+	gas = static_cast<decltype(gas)>(Runtime::getGas());
 	if (auto intResult = result.IntVal.getZExtValue())
 	{
 		auto index = intResult >> 32;

evmcc/Ext.cpp

@@ -9,12 +9,6 @@
 
 #include "Runtime.h"
 
-#ifdef _MSC_VER
-#define EXPORT __declspec(dllexport)
-#else
-#define EXPORT
-#endif
-
 using namespace llvm;
 using llvm::types::i;
 using Linkage = llvm::GlobalValue::LinkageTypes;

evmcc/GasMeter.cpp

@@ -81,7 +81,7 @@ bool isCostBlockEnd(Instruction _inst)
 GasMeter::GasMeter(llvm::IRBuilder<>& _builder, llvm::Module* _module):
 	m_builder(_builder)
 {
-	m_gas = new llvm::GlobalVariable(*_module, Type::i256, false, llvm::GlobalVariable::PrivateLinkage, llvm::UndefValue::get(Type::i256), "gas");
+	m_gas = new llvm::GlobalVariable(*_module, Type::i256, false, llvm::GlobalVariable::ExternalLinkage, nullptr, "gas");
 	m_gas->setUnnamedAddr(true); // Address is not important
 
 	auto pt = m_builder.GetInsertPoint();
@@ -97,21 +97,37 @@ GasMeter::GasMeter(llvm::IRBuilder<>& _builder, llvm::Module* _module):
 	m_builder.SetInsertPoint(bb, pt);
 }
 
-void GasMeter::check(Instruction _inst)
+void GasMeter::count(Instruction _inst)
 {
 	if (!m_checkCall)
 	{
 		// Create gas check call with mocked block cost at begining of current cost-block
-		m_checkCall = m_builder.CreateCall(m_gasCheckFunc, m_builder.getIntN(256, 0));
+		m_checkCall = m_builder.CreateCall(m_gasCheckFunc, llvm::UndefValue::get(Type::i256));
 	}
 	
 	m_blockCost += getStepCost(_inst);
 
 	if (isCostBlockEnd(_inst))
-	{		
-		m_checkCall->setArgOperand(0, m_builder.getIntN(256, m_blockCost)); // Update block cost in gas check call		
+		commitCostBlock();
+}
+
+void GasMeter::commitCostBlock()
+{
+	// If any uncommited block
+	if (m_checkCall)
+	{
+		m_checkCall->setArgOperand(0, m_builder.getIntN(256, m_blockCost)); // Update block cost in gas check call
 		m_checkCall = nullptr; // End cost-block
-	}	
+		m_blockCost = 0;
+	}
+	assert(m_blockCost == 0);
+}
+
+void GasMeter::checkMemory(llvm::Value* _additionalMemoryInWords, llvm::IRBuilder<>& _builder)
+{
+	// Memory uses other builder, but that can be changes later
+	auto cost = _builder.CreateMul(_additionalMemoryInWords, _builder.getIntN(256, static_cast<uint64_t>(c_memoryGas)), "memcost");
+	_builder.CreateCall(m_gasCheckFunc, cost);
 }
 
 }

evmcc/GasMeter.h

@@ -16,16 +16,23 @@ public:
 	GasMeter(const GasMeter&) = delete;
 	void operator=(GasMeter) = delete;
 
-	void check(dev::eth::Instruction _inst);
+	/// Count step cost of instruction
+	void count(dev::eth::Instruction _inst);
+
+	/// Finalize cost block by checking gas needed for the block before the block
+	void commitCostBlock();
+
+	/// Generate code that checks the cost of additional memory used by program
+	void checkMemory(llvm::Value* _additionalMemoryInWords, llvm::IRBuilder<>& _builder);
 
 private:
 	/// Cumulative gas cost of a block of instructions
 	/// @TODO Handle overflow
 	uint64_t m_blockCost = 0;
 	llvm::IRBuilder<>& m_builder;
-	llvm::CallInst* m_checkCall;
+	llvm::CallInst* m_checkCall = nullptr;
 	llvm::GlobalVariable* m_gas;
 	llvm::Function* m_gasCheckFunc;
 };
 
-}
+}

evmcc/Memory.cpp

@@ -13,18 +13,13 @@
 
 #include "Type.h"
 #include "Runtime.h"
-
-#ifdef _MSC_VER
-	#define EXPORT __declspec(dllexport)
-#else
-	#define EXPORT
-#endif
+#include "GasMeter.h"
 
 namespace evmcc
 {
 
-Memory::Memory(llvm::IRBuilder<>& _builder, llvm::Module* _module)
-	: m_builder(_builder)
+Memory::Memory(llvm::IRBuilder<>& _builder, llvm::Module* _module, GasMeter& _gasMeter):
+	m_builder(_builder)
 {
 	auto voidTy	= m_builder.getVoidTy();
 	auto i64Ty = m_builder.getInt64Ty();
@@ -51,12 +46,12 @@ Memory::Memory(llvm::IRBuilder<>& _builder, llvm::Module* _module)
 	m_size->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);
-	m_loadWord = createFunc(false, Type::i256, _module);
-	m_storeWord = createFunc(true, Type::i256, _module);
-	m_storeByte = createFunc(true, Type::Byte, _module);
+	m_loadWord = createFunc(false, Type::i256, _module, _gasMeter);
+	m_storeWord = createFunc(true, Type::i256, _module, _gasMeter);
+	m_storeByte = createFunc(true, Type::Byte, _module, _gasMeter);
 }
 
-llvm::Function* Memory::createFunc(bool _isStore, llvm::Type* _valueType, llvm::Module* _module)
+llvm::Function* Memory::createFunc(bool _isStore, llvm::Type* _valueType, llvm::Module* _module, GasMeter& _gasMeter)
 {
 	auto isWord = _valueType == Type::i256;
 
@@ -69,6 +64,7 @@ llvm::Function* Memory::createFunc(bool _isStore, llvm::Type* _valueType, llvm::
 	auto resizeBB = llvm::BasicBlock::Create(func->getContext(), "resize", func);
 	auto accessBB = llvm::BasicBlock::Create(func->getContext(), "access", func);
 
+	// BB "check"
 	llvm::IRBuilder<> builder(checkBB);
 	llvm::Value* index = func->arg_begin();
 	index->setName("index");
@@ -78,12 +74,20 @@ llvm::Function* Memory::createFunc(bool _isStore, llvm::Type* _valueType, llvm::
 	auto resizeNeeded = builder.CreateICmpULE(size, sizeRequired, "resizeNeeded");
 	builder.CreateCondBr(resizeNeeded, resizeBB, accessBB); // OPT branch weights?
 
+	// BB "resize"
 	builder.SetInsertPoint(resizeBB);
+	// Check gas first
+	auto wordsRequired = builder.CreateUDiv(builder.CreateAdd(sizeRequired, builder.getIntN(256, 31)), builder.getIntN(256, 32), "wordsRequired");
+	auto words = builder.CreateUDiv(builder.CreateAdd(size, builder.getIntN(256, 31)), builder.getIntN(256, 32), "words");
+	auto newWords = builder.CreateSub(wordsRequired, words, "addtionalWords");
+	_gasMeter.checkMemory(newWords, builder);
+	// Resize
 	builder.CreateStore(sizeRequired, m_size);
 	auto newData = builder.CreateCall(m_resize, m_size, "newData");
 	builder.CreateStore(newData, m_data);
 	builder.CreateBr(accessBB);
 
+	// BB "access"
 	builder.SetInsertPoint(accessBB);
 	auto data = builder.CreateLoad(m_data, "data");
 	auto ptr = builder.CreateGEP(data, index, "ptr");

evmcc/Memory.h

@@ -6,11 +6,12 @@
 
 namespace evmcc
 {
+class GasMeter;
 
 class Memory
 {
 public:
-	Memory(llvm::IRBuilder<>& _builder, llvm::Module* _module);
+	Memory(llvm::IRBuilder<>& _builder, llvm::Module* _module, GasMeter& _gasMeter);
 	Memory(const Memory&) = delete;
 	void operator=(Memory) = delete;
 
@@ -22,7 +23,7 @@ public:
 	void dump(uint64_t _begin, uint64_t _end = 0);
 
 private:
-	llvm::Function* createFunc(bool _isStore, llvm::Type* _type, llvm::Module* _module);
+	llvm::Function* createFunc(bool _isStore, llvm::Type* _type, llvm::Module* _module, GasMeter& _gasMeter);
 
 private:
 	llvm::IRBuilder<>& m_builder;

evmcc/Runtime.cpp

@@ -6,11 +6,14 @@ namespace evmcc
 
 static Runtime* g_runtime;
 
-Runtime::Runtime(std::unique_ptr<dev::eth::ExtVMFace> _ext)
-	: m_ext(std::move(_ext))
+extern "C" { EXPORT i256 gas; }
+
+Runtime::Runtime(dev::u256 _gas, std::unique_ptr<dev::eth::ExtVMFace> _ext):
+	m_ext(std::move(_ext))
 {
 	assert(!g_runtime);
 	g_runtime = this;
+	gas = eth2llvm(_gas);
 }
 
 Runtime::~Runtime()
@@ -33,4 +36,9 @@ dev::eth::ExtVMFace& Runtime::getExt()
 	return *g_runtime->m_ext;
 }
 
+dev::u256 Runtime::getGas()
+{
+	return llvm2eth(gas);
+}
+
 }

evmcc/Runtime.h

@@ -7,6 +7,13 @@
 
 #include "Utils.h"
 
+
+#ifdef _MSC_VER
+	#define EXPORT __declspec(dllexport)
+#else
+	#define EXPORT
+#endif
+
 namespace evmcc
 {
 
@@ -16,7 +23,7 @@ using MemoryImpl = dev::bytes;
 class Runtime
 {
 public:
-	Runtime(std::unique_ptr<dev::eth::ExtVMFace> _ext);
+	Runtime(dev::u256 _gas, std::unique_ptr<dev::eth::ExtVMFace> _ext);
 	~Runtime();
 
 	Runtime(const Runtime&) = delete;
@@ -25,6 +32,7 @@ public:
 	static StackImpl& getStack();
 	static MemoryImpl& getMemory();
 	static dev::eth::ExtVMFace& getExt();
+	static dev::u256 getGas();
 
 private:
 	StackImpl m_stack;