[SQUASH] Remove stack implementation.

ethereum · Oct 15, 2020 · 71723aa · 71723aa
1 parent e2ffdb8
commit 71723aa
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Showing 5 changed files with 26 additions and 16 deletions.
diff --git a/libsolidity/codegen/CompilerContext.h b/libsolidity/codegen/CompilerContext.h
@@ -123,9 +123,8 @@ class CompilerContext
 	void setMostDerivedContract(ContractDefinition const& _contract) { m_mostDerivedContract = &_contract; }
 	ContractDefinition const& mostDerivedContract() const;
 
-	void pushArithmetic(Arithmetic _value) { m_arithmetic.push(_value); }
-	void popArithmetic() { m_arithmetic.pop(); }
-	Arithmetic arithmetic() const { return m_arithmetic.empty() ? Arithmetic::Checked : m_arithmetic.top(); }
+	void setArithmetic(Arithmetic _value) { m_arithmetic = _value; }
+	Arithmetic arithmetic() const { return m_arithmetic; }
 
 	/// @returns the next function in the queue of functions that are still to be compiled
 	/// (i.e. that were referenced during compilation but where we did not yet generate code for).
@@ -385,7 +384,7 @@ class CompilerContext
 	/// The contract currently being compiled. Virtual function lookup starts from this contarct.
 	ContractDefinition const* m_mostDerivedContract = nullptr;
 	/// Whether to use checked arithmetic.
-	std::stack<Arithmetic> m_arithmetic;
+	Arithmetic m_arithmetic = Arithmetic::Checked;
 	/// Stack of current visited AST nodes, used for location attachment
 	std::stack<ASTNode const*> m_visitedNodes;
 	/// The runtime context if in Creation mode, this is used for generating tags that would be stored into the storage and then used at runtime.

diff --git a/libsolidity/codegen/ContractCompiler.cpp b/libsolidity/codegen/ContractCompiler.cpp
@@ -1244,23 +1244,31 @@ bool ContractCompiler::visit(PlaceholderStatement const& _placeholderStatement)
 {
 	StackHeightChecker checker(m_context);
 	CompilerContext::LocationSetter locationSetter(m_context, _placeholderStatement);
+	solAssert(m_context.arithmetic() == Arithmetic::Checked, "Placeholder cannot be used inside checked block.");
 	appendModifierOrFunctionCode();
+	solAssert(m_context.arithmetic() == Arithmetic::Checked, "Arithmetic not reset to 'checked'.");
 	checker.check();
 	return true;
 }
 
 bool ContractCompiler::visit(Block const& _block)
 {
 	if (_block.unchecked())
-		m_context.pushArithmetic(Arithmetic::Wrapping);
+	{
+		solAssert(m_context.arithmetic() == Arithmetic::Checked, "");
+		m_context.setArithmetic(Arithmetic::Wrapping);
+	}
 	storeStackHeight(&_block);
 	return true;
 }
 
 void ContractCompiler::endVisit(Block const& _block)
 {
 	if (_block.unchecked())
-		m_context.popArithmetic();
+	{
+		solAssert(m_context.arithmetic() == Arithmetic::Wrapping, "");
+		m_context.setArithmetic(Arithmetic::Checked);
+	}
 	// Frees local variables declared in the scope of this block.
 	popScopedVariables(&_block);
 }
@@ -1328,7 +1336,7 @@ void ContractCompiler::appendModifierOrFunctionCode()
 
 	if (codeBlock)
 	{
-		m_context.pushArithmetic(Arithmetic::Checked);
+		m_context.setArithmetic(Arithmetic::Checked);
 
 		std::set<ExperimentalFeature> experimentalFeaturesOutside = m_context.experimentalFeaturesActive();
 		m_context.setExperimentalFeatures(codeBlock->sourceUnit().annotation().experimentalFeatures);
@@ -1345,8 +1353,6 @@ void ContractCompiler::appendModifierOrFunctionCode()
 		CompilerUtils(m_context).popStackSlots(stackSurplus);
 		for (auto var: addedVariables)
 			m_context.removeVariable(*var);
-
-		m_context.popArithmetic();
 	}
 	m_modifierDepth--;
 	m_context.setModifierDepth(m_modifierDepth);

diff --git a/libsolidity/codegen/ir/IRGenerationContext.h b/libsolidity/codegen/ir/IRGenerationContext.h
@@ -132,9 +132,8 @@ class IRGenerationContext
 
 	langutil::EVMVersion evmVersion() const { return m_evmVersion; };
 
-	void pushArithmetic(Arithmetic _value) { m_arithmetic.push(_value); }
-	void popArithmetic() { m_arithmetic.pop(); }
-	Arithmetic arithmetic() const { return m_arithmetic.empty() ? Arithmetic::Checked : m_arithmetic.top(); }
+	void setArithmetic(Arithmetic _value) { m_arithmetic = _value; }
+	Arithmetic arithmetic() const { return m_arithmetic; }
 
 	ABIFunctions abiFunctions();
 
@@ -166,7 +165,7 @@ class IRGenerationContext
 	MultiUseYulFunctionCollector m_functions;
 	size_t m_varCounter = 0;
 	/// Whether to use checked or wrapping arithmetic.
-	std::stack<Arithmetic> m_arithmetic;
+	Arithmetic m_arithmetic = Arithmetic::Checked;
 
 	/// Flag indicating whether any inline assembly block was seen.
 	bool m_inlineAssemblySeen = false;

diff --git a/libsolidity/codegen/ir/IRGeneratorForStatements.cpp b/libsolidity/codegen/ir/IRGeneratorForStatements.cpp
@@ -477,14 +477,20 @@ bool IRGeneratorForStatements::visit(TupleExpression const& _tuple)
 bool IRGeneratorForStatements::visit(Block const& _block)
 {
 	if (_block.unchecked())
-		m_context.pushArithmetic(Arithmetic::Wrapping);
+	{
+		solAssert(m_context.arithmetic() == Arithmetic::Checked, "");
+		m_context.setArithmetic(Arithmetic::Wrapping);
+	}
 	return true;
 }
 
 void IRGeneratorForStatements::endVisit(Block const& _block)
 {
 	if (_block.unchecked())
-		m_context.popArithmetic();
+	{
+		solAssert(m_context.arithmetic() == Arithmetic::Wrapping, "");
+		m_context.setArithmetic(Arithmetic::Checked);
+	}
 }
 
 bool IRGeneratorForStatements::visit(IfStatement const& _ifStatement)

diff --git a/test/libsolidity/SolidityExpressionCompiler.cpp b/test/libsolidity/SolidityExpressionCompiler.cpp
@@ -139,7 +139,7 @@ bytes compileFirstExpression(
 			);
 			context.resetVisitedNodes(contract);
 			context.setMostDerivedContract(*contract);
-			context.pushArithmetic(Arithmetic::Wrapping);
+			context.setArithmetic(Arithmetic::Wrapping);
 			size_t parametersSize = _localVariables.size(); // assume they are all one slot on the stack
 			context.adjustStackOffset(static_cast<int>(parametersSize));
 			for (vector<string> const& variable: _localVariables)