From 70279f86796ae883a1dfb9b84ebd293cc6e0aff1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Bylica?= <pawel.bylica@imapp.pl>
Date: Tue, 16 Dec 2014 14:46:36 +0100
Subject: [PATCH] Changes in setjmps

---
 libevmjit-cpp/Env.cpp         |  3 +++
 libevmjit/ExecutionEngine.cpp |  6 +++---
 libevmjit/Runtime.cpp         | 27 +++++++++++++++++++++++----
 libevmjit/Runtime.h           | 16 ++++++++++------
 libevmjit/Utils.cpp           |  8 ++++++++
 libevmjit/Utils.h             |  2 ++
 6 files changed, 49 insertions(+), 13 deletions(-)

diff --git a/libevmjit-cpp/Env.cpp b/libevmjit-cpp/Env.cpp
index 11761faf9..72dc062b4 100644
--- a/libevmjit-cpp/Env.cpp
+++ b/libevmjit-cpp/Env.cpp
@@ -67,6 +67,9 @@ extern "C"
 
 	EXPORT bool env_call(ExtVMFace* _env, i256* io_gas, h256* _receiveAddress, i256* _value, byte* _inBeg, uint64_t _inSize, byte* _outBeg, uint64_t _outSize, h256* _codeAddress)
 	{
+		if (_env->depth == 1024)
+			jit::terminate(jit::ReturnCode::OutOfGas);
+
 		assert(_env->depth < 1024);	// TODO: Handle call depth
 
 		auto value = llvm2eth(*_value);
diff --git a/libevmjit/ExecutionEngine.cpp b/libevmjit/ExecutionEngine.cpp
index 3fbc1e413..6e625388d 100644
--- a/libevmjit/ExecutionEngine.cpp
+++ b/libevmjit/ExecutionEngine.cpp
@@ -110,9 +110,9 @@ ReturnCode ExecutionEngine::run(std::unique_ptr<llvm::Module> _module, RuntimeDa
 ReturnCode ExecutionEngine::run(ExecBundle const& _exec, RuntimeData* _data, Env* _env)
 {
 	ReturnCode returnCode;
-	std::jmp_buf buf;
-	Runtime runtime(_data, _env, buf);
-	auto r = setjmp(buf);
+	Runtime runtime(_data, _env);
+
+	auto r = setjmp(runtime.getJmpBuf());
 	if (r == 0)
 	{
 		auto result = _exec.engine->runFunction(_exec.entryFunc, {{}, llvm::GenericValue(&runtime)});
diff --git a/libevmjit/Runtime.cpp b/libevmjit/Runtime.cpp
index e725334db..c0ba5ebee 100644
--- a/libevmjit/Runtime.cpp
+++ b/libevmjit/Runtime.cpp
@@ -5,7 +5,7 @@
 #include <llvm/IR/Function.h>
 #include <llvm/IR/IntrinsicInst.h>
 
-//#include <libevm/VM.h>
+#include <iostream>
 
 namespace dev
 {
@@ -13,12 +13,31 @@ namespace eth
 {
 namespace jit
 {
+namespace
+{
+	jmp_buf_ref g_currJmpBuf;
+}
+
+jmp_buf_ref Runtime::getCurrJmpBuf()
+{
+	return g_currJmpBuf;
+}
 
-Runtime::Runtime(RuntimeData* _data, Env* _env, JmpBufRef _jmpBuf):
+Runtime::Runtime(RuntimeData* _data, Env* _env):
 	m_data(*_data),
 	m_env(*_env),
-	m_jmpBuf(_jmpBuf)
-{}
+	m_currJmpBuf(m_jmpBuf),
+	m_prevJmpBuf(g_currJmpBuf)
+{
+	g_currJmpBuf = m_jmpBuf;
+	std::cerr << "JB push " << g_currJmpBuf << "\n";
+}
+
+Runtime::~Runtime()
+{
+	std::cerr << "JB pop  " << g_currJmpBuf << "\n";
+	g_currJmpBuf = m_prevJmpBuf;
+}
 
 u256 Runtime::getGas() const
 {
diff --git a/libevmjit/Runtime.h b/libevmjit/Runtime.h
index d86acbfc4..adb736ecc 100644
--- a/libevmjit/Runtime.h
+++ b/libevmjit/Runtime.h
@@ -26,12 +26,13 @@ namespace jit
 
 using StackImpl = std::vector<i256>;
 using MemoryImpl = bytes;
-using JmpBufRef = decltype(&jmp_buf{}[0]);
+using jmp_buf_ref = decltype(&std::jmp_buf{}[0]);
 
 class Runtime
 {
 public:
-	Runtime(RuntimeData* _data, Env* _env, JmpBufRef _jmpBuf);
+	Runtime(RuntimeData* _data, Env* _env);
+	~Runtime();
 
 	Runtime(const Runtime&) = delete;
 	void operator=(const Runtime&) = delete;
@@ -42,12 +43,15 @@ public:
 
 	u256 getGas() const;
 	bytes getReturnData() const;
-	JmpBufRef getJmpBuf() { return m_jmpBuf; }
+	jmp_buf_ref getJmpBuf() { return m_jmpBuf; }
+	static jmp_buf_ref getCurrJmpBuf();
 
 private:
-	RuntimeData& m_data;
-	Env& m_env;
-	JmpBufRef m_jmpBuf;
+	RuntimeData& m_data;		///< Pointer to data. Expected by compiled contract.
+	Env& m_env;					///< Pointer to environment proxy. Expected by compiled contract.
+	jmp_buf_ref m_currJmpBuf;	///< Pointer to jump buffer. Expected by compiled contract.
+	jmp_buf_ref m_prevJmpBuf;
+	std::jmp_buf m_jmpBuf;
 	StackImpl m_stack;
 	MemoryImpl m_memory;
 };
diff --git a/libevmjit/Utils.cpp b/libevmjit/Utils.cpp
index 0dad56548..6c2bd81ba 100644
--- a/libevmjit/Utils.cpp
+++ b/libevmjit/Utils.cpp
@@ -1,6 +1,8 @@
 
+#include <csetjmp>
 #include "Utils.h"
 #include "Instruction.h"
+#include "Runtime.h"
 
 namespace dev
 {
@@ -53,6 +55,12 @@ u256 readPushData(bytes::const_iterator& _curr, bytes::const_iterator _end)
 	return value;
 }
 
+void terminate(ReturnCode _returnCode)
+{
+	auto jmpBuf = Runtime::getCurrJmpBuf();
+	std::longjmp(jmpBuf, static_cast<int>(_returnCode));
+}
+
 }
 }
 }
diff --git a/libevmjit/Utils.h b/libevmjit/Utils.h
index f672365c6..db0647fdf 100644
--- a/libevmjit/Utils.h
+++ b/libevmjit/Utils.h
@@ -17,6 +17,8 @@ struct JIT: public NoteChannel  { static const char* name() { return "JIT"; } };
 u256 llvm2eth(i256);
 i256 eth2llvm(u256);
 
+void terminate(ReturnCode _returnCode);
+
 }
 }
 }