Export runtime data to global variable in main function

libevmjit/Compiler.cpp

@@ -175,6 +175,7 @@ std::unique_ptr<llvm::Module> Compiler::compile(bytesConstRef bytecode)
 	createBasicBlocks(bytecode);
 
 	// Init runtime structures.
+	RuntimeManager runtimeManager(m_builder);
 	GasMeter gasMeter(m_builder);
 	Memory memory(m_builder, gasMeter);
 	Ext ext(m_builder);

libevmjit/CompilerHelper.cpp

@@ -21,6 +21,14 @@ llvm::Module* CompilerHelper::getModule()
 	return m_builder.GetInsertBlock()->getParent()->getParent();
 }
 
+llvm::Function* CompilerHelper::getMainFunction()
+{
+	assert(m_builder.GetInsertBlock());
+	auto mainFunc = m_builder.GetInsertBlock()->getParent();
+	assert(mainFunc && mainFunc->getName() == "main");
+	return mainFunc;
+}
+
 }
 }
 }

libevmjit/CompilerHelper.h

@@ -23,6 +23,9 @@ protected:
 	/// Reference to the IR module being compiled
 	llvm::Module* getModule();
 
+	/// Reference to the main module function
+	llvm::Function* getMainFunction();
+
 	/// Reference to parent compiler IR builder
 	llvm::IRBuilder<>& m_builder;
 };

libevmjit/Runtime.cpp

@@ -1,6 +1,9 @@
 
 #include "Runtime.h"
 
+#include <llvm/IR/GlobalVariable.h>
+#include <llvm/IR/Function.h>
+
 #include <libevm/VM.h>
 
 #include "Type.h"
@@ -14,11 +17,16 @@ namespace jit
 
 llvm::StructType* RuntimeData::getType()
 {
-	llvm::Type* elems[] =
+	static llvm::StructType* type = nullptr;
+	if (!type)
 	{
-		Type::i256,
-	};
-	return llvm::StructType::create(elems, "RuntimeData");
+		llvm::Type* elems[] =
+		{
+			Type::i256,
+		};
+		type = llvm::StructType::create(elems, "RuntimeData");
+	}
+	return type;
 }
 
 static Runtime* g_runtime;
@@ -61,6 +69,18 @@ u256 Runtime::getGas()
 	return llvm2eth(gas);
 }
 
+
+RuntimeManager::RuntimeManager(llvm::IRBuilder<>& _builder): CompilerHelper(_builder)
+{
+	auto dataPtrType = RuntimeData::getType()->getPointerTo();
+	m_dataPtr = new llvm::GlobalVariable(*getModule(), dataPtrType, false, llvm::GlobalVariable::PrivateLinkage, llvm::UndefValue::get(dataPtrType), "rt");
+
+	// Export data
+	auto mainFunc = getMainFunction();
+	llvm::Value* dataPtr = &mainFunc->getArgumentList().back();
+	m_builder.CreateStore(dataPtr, m_dataPtr);
+}
+
 }
 }
 }

libevmjit/Runtime.h

@@ -5,6 +5,7 @@
 
 #include <libevm/ExtVMFace.h>
 
+#include "CompilerHelper.h"
 #include "Utils.h"
 
 
@@ -56,6 +57,17 @@ private:
 	ExtVMFace& m_ext;
 };
 
+class RuntimeManager: public CompilerHelper
+{
+public:
+	RuntimeManager(llvm::IRBuilder<>& _builder);
+
+	llvm::Value* getGas();
+
+private:
+	llvm::GlobalVariable* m_dataPtr;
+};
+
 }
 }
 }