Fix clang-tidy performance-unnecessary-copy-initialization warnings

.clang-tidy

@@ -6,6 +6,7 @@ Checks: [-*,
          performance-for-range-copy,
          performance-inefficient-vector-operation,
          performance-move-const-argument,
+         performance-unnecessary-copy-initialization,
 
          # Skipping these temporarily because they are very noisy
          -bugprone-narrowing-conversions,

src/Expr.cc

@@ -1026,8 +1026,8 @@ ValPtr BinaryExpr::TableFold(Val* v1, Val* v2) const {
 }
 
 ValPtr BinaryExpr::AddrFold(Val* v1, Val* v2) const {
-    IPAddr a1 = v1->AsAddr();
+    const IPAddr& a1 = v1->AsAddr();
-    IPAddr a2 = v2->AsAddr();
+    const IPAddr& a2 = v2->AsAddr();
     bool result = false;
 
     switch ( tag ) {

src/broker/Data.cc

@@ -694,8 +694,7 @@ struct type_checker {
         else if ( type->Tag() == TYPE_OPAQUE ) {
             // TODO: Could avoid doing the full unserialization here
             // and just check if the type is a correct match.
-            auto cpy = a;
+            auto ov = OpaqueVal::UnserializeData(BrokerListView{&a});
-            auto ov = OpaqueVal::UnserializeData(BrokerListView{&cpy});
             return ov != nullptr;
         }
 
@@ -729,14 +728,14 @@ std::optional<broker::data> val_to_data(const Val* v) {
             return {broker::port(p->Port(), to_broker_port_proto(p->PortType()))};
         }
         case TYPE_ADDR: {
-            auto a = v->AsAddr();
+            const auto& a = v->AsAddr();
             in6_addr tmp;
             a.CopyIPv6(&tmp);
             return {broker::address(reinterpret_cast<const uint32_t*>(&tmp), broker::address::family::ipv6,
                                     broker::address::byte_order::network)};
         } break;
         case TYPE_SUBNET: {
-            auto s = v->AsSubNet();
+            const auto& s = v->AsSubNet();
             in6_addr tmp;
             s.Prefix().CopyIPv6(&tmp);
             auto a = broker::address(reinterpret_cast<const uint32_t*>(&tmp), broker::address::family::ipv6,

src/script_opt/CPP/Exprs.cc

@@ -1144,7 +1144,7 @@ string CPPCompile::GenListAssign(const ExprPtr& lhs, const ExprPtr& rhs) {
 }
 
 string CPPCompile::GenVectorOp(const Expr* e, string op, const char* vec_op) {
-    auto t = e->GetType();
+    const auto& t = e->GetType();
     auto gen_t = GenTypeName(t);
     auto gen = string("vec_op_") + vec_op + "__CPP(" + op + ", " + gen_t + ")";
 

src/script_opt/CPP/RuntimeInits.cc

@@ -190,7 +190,7 @@ void CPP_IndexedInits<T>::Generate(InitsManager* im, std::vector<AttrPtr>& ivec,
         }
 
         case AE_RECORD: {
-            auto t = im->Types(e_arg);
+            const auto& t = im->Types(e_arg);
             auto rt = cast_intrusive<RecordType>(t);
             auto empty_vals = make_intrusive<ListExpr>();
             auto construct = make_intrusive<RecordConstructorExpr>(empty_vals);
@@ -410,7 +410,7 @@ TypePtr CPP_TypeInits::BuildRecordType(InitsManager* im, ValElemVec& init_vals,
         while ( i < n ) {
             auto s = im->Strings(init_vals[i++]);
             auto id = util::copy_string(s);
-            auto type = im->Types(init_vals[i++]);
+            const auto& type = im->Types(init_vals[i++]);
             auto attrs_i = init_vals[i++];
 
             AttributesPtr attrs;
@@ -439,7 +439,7 @@ int CPP_FieldMapping::ComputeOffset(InitsManager* im) const {
         fm_offset = r->NumFields();
 
         auto id = util::copy_string(field_name.c_str(), field_name.size());
-        auto type = im->Types(field_type);
+        const auto& type = im->Types(field_type);
 
         AttributesPtr attrs;
         if ( field_attrs >= 0 )

src/script_opt/ProfileFunc.cc

@@ -1526,7 +1526,7 @@ ASTBlockAnalyzer::ASTBlockAnalyzer(std::vector<FuncInfo>& funcs) {
 
         auto func = f.Func();
         auto fn = func->GetName();
-        auto body = f.Body();
+        const auto& body = f.Body();
 
         // First get the line numbers all sorted out.
         SetBlockLineNumbers sbln;

src/script_opt/Reduce.cc

@@ -471,7 +471,7 @@ bool Reducer::ExprValid(const ID* id, const Expr* e1, const Expr* e2) const {
     std::optional<ExprSideEffects>& e1_se = e1->GetOptInfo()->SideEffects();
     if ( ! e1_se ) {
         bool has_side_effects = false;
-        auto e1_t = e1->GetType();
+        const auto& e1_t = e1->GetType();
 
         if ( e1_t->Tag() == TYPE_OPAQUE || e1_t->Tag() == TYPE_ANY )
             // These have difficult-to-analyze semantics.

src/script_opt/Stmt.cc

@@ -1104,7 +1104,7 @@ StmtPtr AssertStmt::DoReduce(Reducer* c) {
 
 bool WhenInfo::HasUnreducedIDs(Reducer* c) const {
     for ( auto& cp : *cl ) {
-        auto cid = cp.Id();
+        const auto& cid = cp.Id();
 
         if ( when_new_locals.count(cid.get()) == 0 && ! c->ID_IsReduced(cp.Id()) )
             return true;

src/script_opt/ZAM/BuiltIn.cc

@@ -357,7 +357,7 @@ bool MultiZBI::Build(ZAMCompiler* zam, const NameExpr* n, const ExprPList& args)
                 break;
 
             case 2: {
-                auto c2 = consts[1];
+                const auto& c2 = consts[1];
                 auto c2_t = c2->GetType()->Tag();
 
                 ASSERT(c2_t == TYPE_BOOL || c2_t == TYPE_INT || c2_t == TYPE_COUNT);

src/script_opt/ZAM/Expr.cc

@@ -540,7 +540,7 @@ const ZAMStmt ZAMCompiler::CompileSchedule(const NameExpr* n, const ConstExpr* c
 }
 
 const ZAMStmt ZAMCompiler::CompileEvent(EventHandler* h, const ListExpr* l) {
-    auto exprs = l->Exprs();
+    const auto& exprs = l->Exprs();
     unsigned int n = exprs.length();
 
     bool all_vars = true;
@@ -895,7 +895,7 @@ const ZAMStmt ZAMCompiler::CompileIndex(const NameExpr* n1, int n2_slot, const T
         }
     }
 
-    auto indexes = l->Exprs();
+    const auto& indexes = l->Exprs();
 
     ZOp op;
 
@@ -1515,7 +1515,7 @@ const ZAMStmt ZAMCompiler::ConstructVector(const NameExpr* n, const Expr* e) {
 }
 
 const ZAMStmt ZAMCompiler::ArithCoerce(const NameExpr* n, const Expr* e) {
-    auto nt = n->GetType();
+    const auto& nt = n->GetType();
     auto nt_is_vec = nt->Tag() == TYPE_VECTOR;
 
     auto op = e->GetOp1();

src/script_opt/ZAM/Low-Level.cc

@@ -44,7 +44,7 @@ std::unique_ptr<OpaqueVals> ZAMCompiler::BuildVals(const ListExprPtr& l) {
 }
 
 ZInstAux* ZAMCompiler::InternalBuildVals(const ListExpr* l, int stride) {
-    auto exprs = l->Exprs();
+    const auto& exprs = l->Exprs();
     int n = exprs.length();
 
     auto aux = new ZInstAux(n * stride);

src/script_opt/ZAM/Stmt.cc

@@ -616,7 +616,7 @@ const ZAMStmt ZAMCompiler::TypeSwitch(const SwitchStmt* sw, const NameExpr* v, c
 }
 
 const ZAMStmt ZAMCompiler::CompileWhile(const WhileStmt* ws) {
-    auto loop_condition = ws->Condition();
+    const auto& loop_condition = ws->Condition();
 
     if ( loop_condition->Tag() == EXPR_CONST ) {
         if ( loop_condition->IsZero() )
@@ -1019,7 +1019,7 @@ const ZAMStmt ZAMCompiler::CompileWhen(const WhenStmt* ws) {
     aux->wi = wi;
 
     for ( auto i = 0; i < n; ++i ) {
-        auto la = local_aggr_slots[i];
+        const auto& la = local_aggr_slots[i];
         aux->Add(i, FrameSlot(la), la->GetType());
     }
 
@@ -1072,7 +1072,7 @@ const ZAMStmt ZAMCompiler::CompileAssert(const AssertStmt* as) {
     auto cond_desc = make_intrusive<StringVal>(new String(as->CondDesc()));
     auto cond_desc_e = make_intrusive<ConstExpr>(cond_desc);
 
-    if ( auto msg = as->Msg() ) {
+    if ( const auto& msg = as->Msg() ) {
         auto& msg_setup_stmt = as->MsgSetupStmt();
         if ( msg_setup_stmt )
             (void)CompileStmt(msg_setup_stmt);

src/session/Key.cc

@@ -15,7 +15,7 @@ Key::Key(const void* session, size_t size, size_t type, bool copy) : size(size),
     copied = copy;
 }
 
-Key::Key(Key&& rhs) {
+Key::Key(Key&& rhs) noexcept {
     data = rhs.data;
     size = rhs.size;
     copied = rhs.copied;
@@ -25,7 +25,7 @@ Key::Key(Key&& rhs) {
     rhs.copied = false;
 }
 
-Key& Key::operator=(Key&& rhs) {
+Key& Key::operator=(Key&& rhs) noexcept {
     if ( this != &rhs ) {
         data = rhs.data;
         size = rhs.size;

src/session/Key.h

@@ -44,8 +44,8 @@ public:
 
     // Implement move semantics for Key, since they're used as keys
     // in a map.
-    Key(Key&& rhs);
+    Key(Key&& rhs) noexcept;
-    Key& operator=(Key&& rhs);
+    Key& operator=(Key&& rhs) noexcept;
 
     // Explicitly delete the copy constructor and operator since copying
     // may cause issues with double-freeing pointers.

src/zeekygen/Target.cc

@@ -491,9 +491,7 @@ void ScriptTarget::DoGenerate() const {
             pkg_deps[i]->Generate();
         }
 
-        for ( size_t i = 0; i < dir_contents.size(); ++i ) {
+        for ( const auto& f : dir_contents ) {
-            string f = dir_contents[i];
-
             if ( targets.find(f) != targets.end() )
                 continue;