Hint the compiler that exceptions are exceptional and not the hot path

Change-Id: I981f0cb643a67027a37db38363e26b220d3c216f
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

2 files changed, 9 insertions, 8 deletions

diff --git a/src/qml/jsruntime/qv4functionobject.cpp b/src/qml/jsruntime/qv4functionobject.cpp
index 848b578dea..ee2fe6bfd7 100644
--- a/src/qml/jsruntime/qv4functionobject.cpp
+++ b/src/qml/jsruntime/qv4functionobject.cpp
@@ -435,7 +435,7 @@ void Heap::ScriptFunction::init(QV4::ExecutionContext *scope, Function *function
 void ScriptFunction::construct(const Managed *that, Scope &scope, CallData *callData)
 {
     ExecutionEngine *v4 = scope.engine;
-    if (v4->hasException) {
+    if (Q_UNLIKELY(v4->hasException)) {
         scope.result = Encode::undefined();
         return;
     }
@@ -458,7 +458,7 @@ void ScriptFunction::construct(const Managed *that, Scope &scope, CallData *call
     if (f->function()->hasQmlDependencies)
         QQmlPropertyCapture::registerQmlDependencies(f->function()->compiledFunction, scope);
 
-    if (v4->hasException) {
+    if (Q_UNLIKELY(v4->hasException)) {
         scope.result = Encode::undefined();
     } else if (!scope.result.isObject()) {
         scope.result = obj.asReturnedValue();
@@ -468,7 +468,7 @@ void ScriptFunction::construct(const Managed *that, Scope &scope, CallData *call
 void ScriptFunction::call(const Managed *that, Scope &scope, CallData *callData)
 {
     ExecutionEngine *v4 = scope.engine;
-    if (v4->hasException) {
+    if (Q_UNLIKELY(v4->hasException)) {
         scope.result = Encode::undefined();
         return;
     }
@@ -524,7 +524,7 @@ void Heap::SimpleScriptFunction::init(QV4::ExecutionContext *scope, Function *fu
 void SimpleScriptFunction::construct(const Managed *that, Scope &scope, CallData *callData)
 {
     ExecutionEngine *v4 = scope.engine;
-    if (v4->hasException) {
+    if (Q_UNLIKELY(v4->hasException)) {
         scope.result = Encode::undefined();
         return;
     }
@@ -559,7 +559,7 @@ void SimpleScriptFunction::construct(const Managed *that, Scope &scope, CallData
     if (ff->hasQmlDependencies)
         QQmlPropertyCapture::registerQmlDependencies(f->function()->compiledFunction, scope);
 
-    if (v4->hasException) {
+    if (Q_UNLIKELY(v4->hasException)) {
         scope.result = Encode::undefined();
     } else if (!scope.result.isObject()) {
         scope.result = callData->thisObject;
diff --git a/src/qml/jsruntime/qv4runtime.cpp b/src/qml/jsruntime/qv4runtime.cpp
index 944588dd28..61ef168447 100644
--- a/src/qml/jsruntime/qv4runtime.cpp
+++ b/src/qml/jsruntime/qv4runtime.cpp
@@ -1067,7 +1067,8 @@ ReturnedValue Runtime::method_callPropertyLookup(ExecutionEngine *engine, uint i
     Lookup *l = engine->current->lookups + index;
     Value v;
     v = l->getter(l, engine, callData->thisObject);
-    if (Object *o = v.objectValue()) {
+    Object *o = v.objectValue();
+    if (Q_LIKELY(o)) {
         Scope scope(engine);
         o->call(scope, callData);
         return scope.result.asReturnedValue();
@@ -1170,9 +1171,9 @@ ReturnedValue Runtime::method_constructPropertyLookup(ExecutionEngine *engine, u
     Lookup *l = engine->current->lookups + index;
     Value v;
     v = l->getter(l, engine, callData->thisObject);
-    if (Object *o = v.objectValue()) {
+    Object *o = v.objectValue();
+    if (Q_LIKELY(o)) {
         Scope scope(engine);
-        ScopedValue result(scope);
         o->construct(scope, callData);
         return scope.result.asReturnedValue();
     }