Merge pull request #9652 from ethereum/iceInlineAssemblyOffset

[Sol->Yul] Enabling storage pointers to local vars in inline assembly.

libsolidity/codegen/ir/IRGenerationContext.h

@@ -98,8 +98,9 @@ public:
 
 	void addStateVariable(VariableDeclaration const& _varDecl, u256 _storageOffset, unsigned _byteOffset);
 	bool isStateVariable(VariableDeclaration const& _varDecl) const { return m_stateVariables.count(&_varDecl); }
-	std::pair<u256, unsigned> storageLocationOfVariable(VariableDeclaration const& _varDecl) const
+	std::pair<u256, unsigned> storageLocationOfStateVariable(VariableDeclaration const& _varDecl) const
 	{
+		solAssert(isStateVariable(_varDecl), "");
 		return m_stateVariables.at(&_varDecl);
 	}
 

libsolidity/codegen/ir/IRGenerator.cpp

@@ -305,7 +305,7 @@ string IRGenerator::generateGetter(VariableDeclaration const& _varDecl)
 
 		string code;
 
-		auto const& location = m_context.storageLocationOfVariable(_varDecl);
+		auto const& location = m_context.storageLocationOfStateVariable(_varDecl);
 		code += Whiskers(R"(
 			let slot := <slot>
 			let offset := <offset>

libsolidity/codegen/ir/IRGeneratorForStatements.cpp

@@ -75,18 +75,30 @@ struct CopyTranslate: public yul::ASTCopier
 			{
 				solAssert(reference.isOffset != reference.isSlot, "");
 
-				pair<u256, unsigned> slot_offset = m_context.storageLocationOfVariable(*varDecl);
+				string value;
+				if (varDecl->isStateVariable())
+					value =
+						reference.isSlot ?
+							m_context.storageLocationOfStateVariable(*varDecl).first.str() :
+							to_string(m_context.storageLocationOfStateVariable(*varDecl).second);
+				else
+				{
+					solAssert(varDecl->isLocalVariable(), "");
+					if (reference.isSlot)
+						value = IRVariable{*varDecl}.part("slot").name();
+					else if (varDecl->type()->isValueType())
+						value = IRVariable{*varDecl}.part("offset").name();
+					else
+					{
+						solAssert(!IRVariable{*varDecl}.hasPart("offset"), "");
+						value = "0";
+					}
+				}
 
-				string const value = reference.isSlot ?
-					slot_offset.first.str() :
-					to_string(slot_offset.second);
-
-				return yul::Literal{
-					_identifier.location,
-					yul::LiteralKind::Number,
-					yul::YulString{value},
-					{}
-				};
+				if (isdigit(value.front()))
+					return yul::Literal{_identifier.location, yul::LiteralKind::Number, yul::YulString{value}, {}};
+				else
+					return yul::Identifier{_identifier.location, yul::YulString{value}};
 			}
 		}
 		return ASTCopier::operator()(_identifier);
@@ -152,8 +164,8 @@ void IRGeneratorForStatements::initializeStateVar(VariableDeclaration const& _va
 		_varDecl.immutable() ?
 		IRLValue{*_varDecl.annotation().type, IRLValue::Immutable{&_varDecl}} :
 		IRLValue{*_varDecl.annotation().type, IRLValue::Storage{
-			util::toCompactHexWithPrefix(m_context.storageLocationOfVariable(_varDecl).first),
-			m_context.storageLocationOfVariable(_varDecl).second
+			util::toCompactHexWithPrefix(m_context.storageLocationOfStateVariable(_varDecl).first),
+			m_context.storageLocationOfStateVariable(_varDecl).second
 		}},
 		*_varDecl.value()
 	);
@@ -2026,8 +2038,8 @@ void IRGeneratorForStatements::handleVariableReference(
 		setLValue(_referencingExpression, IRLValue{
 			*_variable.annotation().type,
 			IRLValue::Storage{
-				toCompactHexWithPrefix(m_context.storageLocationOfVariable(_variable).first),
-				m_context.storageLocationOfVariable(_variable).second
+				toCompactHexWithPrefix(m_context.storageLocationOfStateVariable(_variable).first),
+				m_context.storageLocationOfStateVariable(_variable).second
 			}
 		});
 	else

libsolidity/codegen/ir/IRVariable.cpp

@@ -53,6 +53,17 @@ IRVariable IRVariable::part(string const& _name) const
 	solAssert(false, "Invalid stack item name: " + _name);
 }
 
+bool IRVariable::hasPart(std::string const& _name) const
+{
+	for (auto const& [itemName, itemType]: m_type.stackItems())
+		if (itemName == _name)
+		{
+			solAssert(itemName.empty() || itemType, "");
+			return true;
+		}
+	return false;
+}
+
 vector<string> IRVariable::stackSlots() const
 {
 	vector<string> result;

libsolidity/codegen/ir/IRVariable.h

@@ -71,6 +71,10 @@ public:
 	/// in ``m_type.stackItems()`` and may again occupy multiple stack slots.
 	IRVariable part(std::string const& _slot) const;
 
+	/// @returns true if variable contains @a _name component
+	/// @a _name name of the component that is being checked
+	bool hasPart(std::string const& _name) const;
+
 	/// @returns a vector containing the names of the stack slots of the variable.
 	std::vector<std::string> stackSlots() const;
 

test/libsolidity/semanticTests/inlineAssembly/inline_assembly_storage_access_local_var.sol

@@ -0,0 +1,18 @@
+contract C {
+    uint256[] public a;
+
+    function f() public returns (uint256) {
+        uint256[] storage x = a;
+        uint256 off;
+        assembly {
+            sstore(x.slot, 7)
+            off := x.offset
+        }
+        assert(off == 0);
+        return a.length;
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// f() -> 7