Merge pull request #11615 from ethereum/yulStackLayoutGenerator

Yul Stack Layout Generator (New Code Transform Step 2)

Author: ekpyron

libsolutil/CommonData.h

@@ -52,6 +52,21 @@ template <class T, class U> std::vector<T>& operator+=(std::vector<T>& _a, U&& _
 	std::move(_b.begin(), _b.end(), std::back_inserter(_a));
 	return _a;
 }
+
+/// Concatenate the contents of a container onto a list
+template <class T, class U> std::list<T>& operator+=(std::list<T>& _a, U& _b)
+{
+	for (auto const& i: _b)
+		_a.push_back(T(i));
+	return _a;
+}
+/// Concatenate the contents of a container onto a list, move variant.
+template <class T, class U> std::list<T>& operator+=(std::list<T>& _a, U&& _b)
+{
+	std::move(_b.begin(), _b.end(), std::back_inserter(_a));
+	return _a;
+}
+
 /// Concatenate the contents of a container onto a multiset
 template <class U, class... T> std::multiset<T...>& operator+=(std::multiset<T...>& _a, U& _b)
 {
@@ -321,6 +336,44 @@ void joinMap(std::map<K, V>& _a, std::map<K, V>&& _b, F _conflictSolver)
 	}
 }
 
+namespace detail
+{
+
+template<typename Container, typename Value>
+auto findOffset(Container&& _container, Value&& _value, int)
+-> decltype(_container.find(_value) == _container.end(), std::distance(_container.begin(), _container.find(_value)), std::optional<size_t>())
+{
+	auto it = _container.find(std::forward<Value>(_value));
+	auto end = _container.end();
+	if (it == end)
+		return std::nullopt;
+	return std::distance(_container.begin(), it);
+}
+template<typename Range, typename Value>
+auto findOffset(Range&& _range, Value&& _value, void*)
+-> decltype(std::find(std::begin(_range), std::end(_range), std::forward<Value>(_value)) == std::end(_range), std::optional<size_t>())
+{
+	auto begin = std::begin(_range);
+	auto end = std::end(_range);
+	auto it = std::find(begin, end, std::forward<Value>(_value));
+	if (it == end)
+		return std::nullopt;
+	return std::distance(begin, it);
+}
+
+}
+
+/// @returns an std::optional<size_t> containing the offset of the first element in @a _range that is equal to @a _value,
+/// if any, or std::nullopt otherwise.
+/// Uses a linear search (``std::find``) unless @a _range is a container and provides a
+/// suitable ``.find`` function (e.g. it will use the logarithmic ``.find`` function in ``std::set`` instead).
+template<typename Range>
+auto findOffset(Range&& _range, std::remove_reference_t<decltype(*std::cbegin(_range))> const& _value)
+-> decltype(detail::findOffset(std::forward<Range>(_range), _value, 0))
+{
+	return detail::findOffset(std::forward<Range>(_range), _value, 0);
+}
+
 // String conversion functions, mainly to/from hex/nibble/byte representations.
 
 enum class WhenError

libyul/CMakeLists.txt

@@ -68,6 +68,9 @@ add_library(yul
 	backends/evm/EVMMetrics.h
 	backends/evm/NoOutputAssembly.h
 	backends/evm/NoOutputAssembly.cpp
+	backends/evm/StackHelpers.h
+	backends/evm/StackLayoutGenerator.h
+	backends/evm/StackLayoutGenerator.cpp
 	backends/evm/VariableReferenceCounter.h
 	backends/evm/VariableReferenceCounter.cpp
 	backends/wasm/EVMToEwasmTranslator.cpp

libyul/backends/evm/ControlFlowGraph.h

@@ -24,6 +24,7 @@
 #include <libyul/AST.h>
 #include <libyul/AsmAnalysisInfo.h>
 #include <libyul/Dialect.h>
+#include <libyul/Exceptions.h>
 #include <libyul/Scope.h>
 
 #include <functional>
@@ -54,8 +55,19 @@ struct FunctionCallReturnLabelSlot
 /// the function.
 struct FunctionReturnLabelSlot
 {
-	bool operator==(FunctionReturnLabelSlot const&) const { return true; }
-	bool operator<(FunctionReturnLabelSlot const&) const { return false; }
+	std::reference_wrapper<Scope::Function const> function;
+	bool operator==(FunctionReturnLabelSlot const& _rhs) const
+	{
+		// There can never be return label slots of different functions on stack simultaneously.
+		yulAssert(&function.get() == &_rhs.function.get(), "");
+		return true;
+	}
+	bool operator<(FunctionReturnLabelSlot const& _rhs) const
+	{
+		// There can never be return label slots of different functions on stack simultaneously.
+		yulAssert(&function.get() == &_rhs.function.get(), "");
+		return false;
+	}
 	static constexpr bool canBeFreelyGenerated = false;
 };
 /// A slot containing the current value of a particular variable.