1 files changed, 42 insertions, 20 deletions

diff --git a/liblll/CodeFragment.cpp b/liblll/CodeFragment.cpp
index 2b8822a6..56c1e26a 100644
--- a/liblll/CodeFragment.cpp
+++ b/liblll/CodeFragment.cpp
@@ -171,11 +171,23 @@ void CodeFragment::constructOperation(sp::utree const& _t, CompilerState& _s)
 			return string();
 		};
 
-		auto varAddress = [&](string const& n)
+		auto varAddress = [&](string const& n, bool createMissing = false)
 		{
+			if (n.empty())
+				error<InvalidName>("Empty variable name not allowed");
 			auto it = _s.vars.find(n);
 			if (it == _s.vars.end())
-				error<InvalidName>(std::string("Symbol not found: ") + s);
+			{
+				if (createMissing)
+				{
+					// Create new variable
+					bool ok;
+					tie(it, ok) = _s.vars.insert(make_pair(n, make_pair(_s.stackSize, 32)));
+					_s.stackSize += 32;
+				}
+				else
+					error<InvalidName>(std::string("Symbol not found: ") + n);
+			}
 			return it->second.first;
 		};
 
@@ -192,7 +204,13 @@ void CodeFragment::constructOperation(sp::utree const& _t, CompilerState& _s)
 		{
 			if (_t.size() != 2)
 				error<IncorrectParameterCount>();
-			m_asm.append(CodeFragment::compile(contentsString(firstAsString()), _s).m_asm);
+			string fileName = firstAsString();
+			if (fileName.empty())
+				error<InvalidName>("Empty file name provided");
+			string contents = contentsString(fileName);
+			if (contents.empty())
+				error<InvalidName>(std::string("File not found (or empty): ") + fileName);
+			m_asm.append(CodeFragment::compile(contents, _s).m_asm);
 		}
 		else if (us == "SET")
 		{
@@ -202,7 +220,7 @@ void CodeFragment::constructOperation(sp::utree const& _t, CompilerState& _s)
 			for (auto const& i: _t)
 				if (c++ == 2)
 					m_asm.append(CodeFragment(i, _s, false).m_asm);
-			m_asm.append((u256)varAddress(firstAsString()));
+			m_asm.append((u256)varAddress(firstAsString(), true));
 			m_asm.append(Instruction::MSTORE);
 		}
 		else if (us == "GET")
@@ -240,7 +258,11 @@ void CodeFragment::constructOperation(sp::utree const& _t, CompilerState& _s)
 				}
 				else if (ii == 2)
 					if (_t.size() == 3)
-						_s.defs[n] = CodeFragment(i, _s);
+					{
+						/// NOTE: some compilers could do the assignment first if this is done in a single line
+						CodeFragment code = CodeFragment(i, _s);
+						_s.defs[n] = code;
+					}
 					else
 						for (auto const& j: i)
 						{
@@ -439,15 +461,21 @@ void CodeFragment::constructOperation(sp::utree const& _t, CompilerState& _s)
 			int minDep = min(code[1].m_asm.deposit(), code[2].m_asm.deposit());
 
 			m_asm.append(code[0].m_asm);
-			auto pos = m_asm.appendJumpI();
-			m_asm.onePath();
+			auto mainBranch = m_asm.appendJumpI();
+
+			/// The else branch.
+			int startDeposit = m_asm.deposit();
 			m_asm.append(code[2].m_asm, minDep);
 			auto end = m_asm.appendJump();
-			m_asm.otherPath();
-			m_asm << pos.tag();
+			int deposit = m_asm.deposit();
+			m_asm.setDeposit(startDeposit);
+
+			/// The main branch.
+			m_asm << mainBranch.tag();
 			m_asm.append(code[1].m_asm, minDep);
 			m_asm << end.tag();
-			m_asm.donePaths();
+			if (m_asm.deposit() != deposit)
+				error<InvalidDeposit>();
 		}
 		else if (us == "WHEN" || us == "UNLESS")
 		{
@@ -458,11 +486,8 @@ void CodeFragment::constructOperation(sp::utree const& _t, CompilerState& _s)
 			if (us == "WHEN")
 				m_asm.append(Instruction::ISZERO);
 			auto end = m_asm.appendJumpI();
-			m_asm.onePath();
-			m_asm.otherPath();
 			m_asm.append(code[1].m_asm, 0);
 			m_asm << end.tag();
-			m_asm.donePaths();
 		}
 		else if (us == "WHILE" || us == "UNTIL")
 		{
@@ -515,8 +540,7 @@ void CodeFragment::constructOperation(sp::utree const& _t, CompilerState& _s)
 			requireMaxSize(3);
 			requireDeposit(1, 1);
 
-			auto subPush = m_asm.newSub(make_shared<Assembly>(code[0].assembly(ns)));
-			m_asm.append(m_asm.newPushSubSize(subPush.data()));
+			auto subPush = m_asm.appendSubroutine(make_shared<Assembly>(code[0].assembly(ns)));
 			m_asm.append(Instruction::DUP1);
 			if (code.size() == 3)
 			{
@@ -571,11 +595,9 @@ void CodeFragment::constructOperation(sp::utree const& _t, CompilerState& _s)
 		{
 			for (auto const& i: code)
 				m_asm.append(i.m_asm);
-			m_asm.popTo(1);
-		}
-		else if (us == "PANIC")
-		{
-			m_asm.appendJump(m_asm.errorTag());
+			// Leave only the last item on stack.
+			while (m_asm.deposit() > 1)
+				m_asm.append(Instruction::POP);
 		}
 		else if (us == "BYTECODESIZE")
 		{