[Sol->Yul] Implement index access for storage arrays

libsolidity/codegen/ir/IRGeneratorForStatements.cpp

@@ -820,7 +820,45 @@ void IRGeneratorForStatements::endVisit(IndexAccess const& _indexAccess)
 		));
 	}
 	else if (baseType.category() == Type::Category::Array)
-		solUnimplementedAssert(false, "");
+	{
+		ArrayType const& arrayType = dynamic_cast<ArrayType const&>(baseType);
+		solAssert(_indexAccess.indexExpression(), "Index expression expected.");
+
+		switch (arrayType.location())
+		{
+			case DataLocation::Storage:
+			{
+				string slot = m_context.newYulVariable();
+				string offset = m_context.newYulVariable();
+
+				m_code << Whiskers(R"(
+					let <slot>, <offset> := <indexFunc>(<array>, <index>)
+				)")
+				("slot", slot)
+				("offset", offset)
+				("indexFunc", m_utils.storageArrayIndexAccessFunction(arrayType))
+				("array", m_context.variable(_indexAccess.baseExpression()))
+				("index", m_context.variable(*_indexAccess.indexExpression()))
+				.render();
+
+				setLValue(_indexAccess, make_unique<IRStorageItem>(
+					m_context,
+					slot,
+					offset,
+					*_indexAccess.annotation().type
+				));
+
+				break;
+			}
+			case DataLocation::Memory:
+				solUnimplementedAssert(false, "");
+				break;
+			case DataLocation::CallData:
+				solUnimplementedAssert(false, "");
+				break;
+		}
+
+	}
 	else if (baseType.category() == Type::Category::FixedBytes)
 		solUnimplementedAssert(false, "");
 	else if (baseType.category() == Type::Category::TypeType)

libsolidity/codegen/ir/IRLValue.cpp

@@ -135,7 +135,8 @@ string IRStorageItem::storeValue(string const& _value, Type const& _sourceType)
 
 string IRStorageItem::setToZero() const
 {
-	solUnimplemented("Delete for storage location not yet implemented");
+	solUnimplementedAssert(m_type->isValueType(), "");
+	return storeValue(m_context.utils().zeroValueFunction(*m_type) + "()", *m_type);
 }
 
 IRStorageArrayLength::IRStorageArrayLength(IRGenerationContext& _context, string _slot, Type const& _type, ArrayType const& _arrayType):