Fix some clang tidy warnings

Mostly adding noexcept to some move assignments/ctors so they are
utilized by STL. Also adding some std::move calls to avoid certain
potentially expensive copies. Some misc fixes/improvements including
fixing typos in comments.

Author: Xazax-hun

src/ast/Constraint.h

@@ -28,7 +28,7 @@ class Constraint : public Literal {
 public:
     using Literal::Literal;
 
-    Constraint(NodeKind kind, SrcLocation loc = {}) : Literal(kind, loc) {
+    Constraint(NodeKind kind, SrcLocation loc = {}) : Literal(kind, std::move(loc)) {
         assert(kind >= NK_Constraint && kind < NK_LastConstraint);
     }
 

src/ast/Functor.h

@@ -29,7 +29,7 @@ class Functor : public Term {
 protected:
     using Term::Term;
 
-    Functor(NodeKind kind, SrcLocation loc = {}) : Term(kind, loc) {
+    Functor(NodeKind kind, SrcLocation loc = {}) : Term(kind, std::move(loc)) {
         assert(kind > NK_FirstFunctor && kind < NK_LastFunctor);
     }
 

src/ast/Lattice.cpp

@@ -42,7 +42,7 @@ void Lattice::setQualifiedName(QualifiedName name) {
     this->name = std::move(name);
 }
 
-const std::map<LatticeOperator, const ast::Argument*> Lattice::getOperators() const {
+std::map<LatticeOperator, const ast::Argument*> Lattice::getOperators() const {
     std::map<LatticeOperator, const ast::Argument*> ops;
     for (const auto& [op, arg] : operators) {
         ops.emplace(std::make_pair(op, arg.get()));

src/ast/Lattice.h

@@ -47,7 +47,7 @@ class Lattice : public Node {
     /** Set type name */
     void setQualifiedName(QualifiedName name);
 
-    const std::map<LatticeOperator, const ast::Argument*> getOperators() const;
+    std::map<LatticeOperator, const ast::Argument*> getOperators() const;
 
     bool hasGlb() const;
     bool hasLub() const;

src/ast/Literal.h

@@ -31,7 +31,7 @@ class Literal : public Node {
 public:
     using Node::Node;
 
-    explicit Literal(NodeKind kind, SrcLocation loc = {}) : Node(kind, loc) {
+    explicit Literal(NodeKind kind, SrcLocation loc = {}) : Node(kind, std::move(loc)) {
         assert(kind >= NK_Literal && kind < NK_LastLiteral);
     }
 

src/ast/UnnamedVariable.cpp

@@ -11,7 +11,7 @@
 
 namespace souffle::ast {
 
-UnnamedVariable::UnnamedVariable(SrcLocation loc) : Argument(NK_UnnamedVariable, loc) {}
+UnnamedVariable::UnnamedVariable(SrcLocation loc) : Argument(NK_UnnamedVariable, std::move(loc)) {}
 
 void UnnamedVariable::print(std::ostream& os) const {
     os << "_";

src/ast/UserDefinedAggregator.cpp

@@ -19,7 +19,7 @@
 namespace souffle::ast {
 UserDefinedAggregator::UserDefinedAggregator(
         std::string name, Own<Argument> init, Own<Argument> expr, VecOwn<Literal> body, SrcLocation loc)
-        : Aggregator(NK_UserDefinedAggregator, std::move(expr), std::move(body), std::move(loc)), name(name),
+        : Aggregator(NK_UserDefinedAggregator, std::move(expr), std::move(body), std::move(loc)), name(std::move(name)),
           initValue(std::move(init)) {}
 
 void UserDefinedAggregator::apply(const NodeMapper& map) {

src/ast/analysis/Aggregate.cpp

@@ -105,7 +105,7 @@ std::set<std::string> getWitnessVariables(
     M update;
     aggregatorlessClause->apply(update);
     auto groundingAtom = mk<Atom>(QualifiedName::fromString("+grounding_atom"));
-    for (std::string variableName : update.getAggregatorVariables()) {
+    for (const std::string& variableName : update.getAggregatorVariables()) {
         groundingAtom->addArgument(mk<Variable>(variableName));
     }
     aggregatorlessClause->addToBody(std::move(groundingAtom));
@@ -163,7 +163,7 @@ std::set<std::string> getVariablesOutsideAggregate(const Clause& clause, const A
     return variablesOutsideAggregate;
 }
 
-std::string findUniqueVariableName(const Clause& clause, std::string base) {
+std::string findUniqueVariableName(const Clause& clause, const std::string& base) {
     std::set<std::string> variablesInClause;
     visit(clause, [&](const Variable& v) { variablesInClause.insert(v.getName()); });
     int varNum = 0;
@@ -174,7 +174,7 @@ std::string findUniqueVariableName(const Clause& clause, std::string base) {
     return candidate;
 }
 
-std::string findUniqueRelationName(const Program& program, std::string base) {
+std::string findUniqueRelationName(const Program& program, const std::string& base) {
     int counter = 0;
     auto candidate = base;
     while (program.getRelation(QualifiedName::fromString(candidate)) != nullptr) {
@@ -331,7 +331,7 @@ std::set<std::string> getInjectedVariables(
     tweakedClause->apply(update);
     // the update will now tell us which variables we need to ground!
     auto groundingAtom = mk<Atom>(QualifiedName::fromString("+grounding_atom"));
-    for (std::string variableName : update.getAggregatorVariables()) {
+    for (const std::string& variableName : update.getAggregatorVariables()) {
         groundingAtom->addArgument(mk<Variable>(variableName));
     }
     // add the newly created grounding atom to the body

src/ast/analysis/IOType.h

@@ -60,8 +60,8 @@ class IOTypeAnalysis : public Analysis {
         auto iter = limitSize.find(relation);
         if (iter != limitSize.end()) {
             return (*iter).second;
-        } else
-            return 0;
+        }
+        return 0;
     }
 
     bool isIO(const Relation* relation) const {

src/ast/analysis/typesystem/TypeSystem.h

@@ -311,8 +311,8 @@ struct RecordType : public Type {
 
 protected:
     RecordType(const TypeEnvironment& environment, const QualifiedName& name,
-            const std::vector<const Type*> fields = {})
-            : Type(TK_RecordType, environment, name), fields(fields) {}
+            std::vector<const Type*> fields = {})
+            : Type(TK_RecordType, environment, name), fields(std::move(fields)) {}
 
 private:
     friend class TypeEnvironment;