Use Q_UNLIKELY for every qFatal()/qCritical()

If, after checking a condition, we issue a qFatal()
or a qCritical(), by definition that check is
unlikely to be true.

Tell the compiler so it can move the error handling
code out of the normal code path to increase the
effective icache size.

Moved conditional code around where possible so that
we could always use Q_UNLIKELY, instead of having to
revert to Q_LIKELY here and there.

In some cases, simplified the expressions newly wrapped
in Q_UNLIKELY as a drive-by.

Change-Id: I67537d62b04bc6977d69254690c5ebbdf98bfd6d
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>

6 files changed, 19 insertions, 19 deletions

diff --git a/src/plugins/platforms/android/androidjnimain.cpp b/src/plugins/platforms/android/androidjnimain.cpp
index d419e42cd5..9a96534c38 100644
--- a/src/plugins/platforms/android/androidjnimain.cpp
+++ b/src/plugins/platforms/android/androidjnimain.cpp
@@ -487,7 +487,7 @@ static jboolean startQtApplication(JNIEnv *env, jobject /*object*/, jstring para
         // Obtain a handle to the main library (the library that contains the main() function).
         // This library should already be loaded, and calling dlopen() will just return a reference to it.
         m_mainLibraryHnd = dlopen(m_applicationParams.first().data(), 0);
-        if (m_mainLibraryHnd == nullptr) {
+        if (Q_UNLIKELY(!m_mainLibraryHnd)) {
             qCritical() << "dlopen failed:" << dlerror();
             return false;
         }
@@ -497,7 +497,7 @@ static jboolean startQtApplication(JNIEnv *env, jobject /*object*/, jstring para
         m_main = (Main)dlsym(RTLD_DEFAULT, "main");
     }
 
-    if (!m_main) {
+    if (Q_UNLIKELY(!m_main)) {
         qCritical() << "dlsym failed:" << dlerror();
         qCritical() << "Could not find main method";
         return false;
diff --git a/src/plugins/platforms/android/qandroidinputcontext.cpp b/src/plugins/platforms/android/qandroidinputcontext.cpp
index e3ea048e84..92c0c2cf0f 100644
--- a/src/plugins/platforms/android/qandroidinputcontext.cpp
+++ b/src/plugins/platforms/android/qandroidinputcontext.cpp
@@ -339,7 +339,7 @@ QAndroidInputContext::QAndroidInputContext()
     : QPlatformInputContext(), m_composingTextStart(-1), m_blockUpdateSelection(false),  m_batchEditNestingLevel(0), m_focusObject(0)
 {
     jclass clazz = QJNIEnvironmentPrivate::findClass(QtNativeInputConnectionClassName);
-    if (clazz == NULL) {
+    if (Q_UNLIKELY(!clazz)) {
         qCritical() << "Native registration unable to find class '"
                     << QtNativeInputConnectionClassName
                     << '\'';
@@ -347,7 +347,7 @@ QAndroidInputContext::QAndroidInputContext()
     }
 
     QJNIEnvironmentPrivate env;
-    if (env->RegisterNatives(clazz, methods, sizeof(methods) / sizeof(methods[0])) < 0) {
+    if (Q_UNLIKELY(env->RegisterNatives(clazz, methods, sizeof(methods) / sizeof(methods[0])) < 0)) {
         qCritical() << "RegisterNatives failed for '"
                     << QtNativeInputConnectionClassName
                     << '\'';
@@ -355,7 +355,7 @@ QAndroidInputContext::QAndroidInputContext()
     }
 
     clazz = QJNIEnvironmentPrivate::findClass(QtExtractedTextClassName);
-    if (clazz == NULL) {
+    if (Q_UNLIKELY(!clazz)) {
         qCritical() << "Native registration unable to find class '"
                     << QtExtractedTextClassName
                     << '\'';
@@ -364,43 +364,43 @@ QAndroidInputContext::QAndroidInputContext()
 
     m_extractedTextClass = static_cast<jclass>(env->NewGlobalRef(clazz));
     m_classConstructorMethodID = env->GetMethodID(m_extractedTextClass, "<init>", "()V");
-    if (m_classConstructorMethodID == NULL) {
+    if (Q_UNLIKELY(!m_classConstructorMethodID)) {
         qCritical() << "GetMethodID failed";
         return;
     }
 
     m_partialEndOffsetFieldID = env->GetFieldID(m_extractedTextClass, "partialEndOffset", "I");
-    if (m_partialEndOffsetFieldID == NULL) {
+    if (Q_UNLIKELY(!m_partialEndOffsetFieldID)) {
         qCritical() << "Can't find field partialEndOffset";
         return;
     }
 
     m_partialStartOffsetFieldID = env->GetFieldID(m_extractedTextClass, "partialStartOffset", "I");
-    if (m_partialStartOffsetFieldID == NULL) {
+    if (Q_UNLIKELY(!m_partialStartOffsetFieldID)) {
         qCritical() << "Can't find field partialStartOffset";
         return;
     }
 
     m_selectionEndFieldID = env->GetFieldID(m_extractedTextClass, "selectionEnd", "I");
-    if (m_selectionEndFieldID == NULL) {
+    if (Q_UNLIKELY(!m_selectionEndFieldID)) {
         qCritical() << "Can't find field selectionEnd";
         return;
     }
 
     m_selectionStartFieldID = env->GetFieldID(m_extractedTextClass, "selectionStart", "I");
-    if (m_selectionStartFieldID == NULL) {
+    if (Q_UNLIKELY(!m_selectionStartFieldID)) {
         qCritical() << "Can't find field selectionStart";
         return;
     }
 
     m_startOffsetFieldID = env->GetFieldID(m_extractedTextClass, "startOffset", "I");
-    if (m_startOffsetFieldID == NULL) {
+    if (Q_UNLIKELY(!m_startOffsetFieldID)) {
         qCritical() << "Can't find field startOffset";
         return;
     }
 
     m_textFieldID = env->GetFieldID(m_extractedTextClass, "text", "Ljava/lang/String;");
-    if (m_textFieldID == NULL) {
+    if (Q_UNLIKELY(!m_textFieldID)) {
         qCritical() << "Can't find field text";
         return;
     }
diff --git a/src/plugins/platforms/android/qandroidplatformfontdatabase.cpp b/src/plugins/platforms/android/qandroidplatformfontdatabase.cpp
index a8bbec9400..835ca8a10a 100644
--- a/src/plugins/platforms/android/qandroidplatformfontdatabase.cpp
+++ b/src/plugins/platforms/android/qandroidplatformfontdatabase.cpp
@@ -47,7 +47,7 @@ void QAndroidPlatformFontDatabase::populateFontDatabase()
     QString fontpath = fontDir();
     QDir dir(fontpath);
 
-    if (!dir.exists()) {
+    if (Q_UNLIKELY(!dir.exists())) {
         qFatal("QFontDatabase: Cannot find font directory %s - is Qt installed correctly?",
                qPrintable(fontpath));
     }
diff --git a/src/plugins/platforms/android/qandroidplatformintegration.cpp b/src/plugins/platforms/android/qandroidplatformintegration.cpp
index 2a127f5c3c..23d242a95f 100644
--- a/src/plugins/platforms/android/qandroidplatformintegration.cpp
+++ b/src/plugins/platforms/android/qandroidplatformintegration.cpp
@@ -120,14 +120,14 @@ QAndroidPlatformIntegration::QAndroidPlatformIntegration(const QStringList &para
     m_androidPlatformNativeInterface = new QAndroidPlatformNativeInterface();
 
     m_eglDisplay = eglGetDisplay(EGL_DEFAULT_DISPLAY);
-    if (m_eglDisplay == EGL_NO_DISPLAY)
+    if (Q_UNLIKELY(m_eglDisplay == EGL_NO_DISPLAY))
         qFatal("Could not open egl display");
 
     EGLint major, minor;
-    if (!eglInitialize(m_eglDisplay, &major, &minor))
+    if (Q_UNLIKELY(!eglInitialize(m_eglDisplay, &major, &minor)))
         qFatal("Could not initialize egl display");
 
-    if (!eglBindAPI(EGL_OPENGL_ES_API))
+    if (Q_UNLIKELY(!eglBindAPI(EGL_OPENGL_ES_API)))
         qFatal("Could not bind GL_ES API");
 
     m_primaryScreen = new QAndroidPlatformScreen();
diff --git a/src/plugins/platforms/android/qandroidplatformopenglwindow.cpp b/src/plugins/platforms/android/qandroidplatformopenglwindow.cpp
index 57d3bfaf22..85f51d7d29 100644
--- a/src/plugins/platforms/android/qandroidplatformopenglwindow.cpp
+++ b/src/plugins/platforms/android/qandroidplatformopenglwindow.cpp
@@ -175,7 +175,7 @@ void QAndroidPlatformOpenGLWindow::createEgl(EGLConfig config)
     m_androidSurfaceObject = QJNIObjectPrivate();
     m_eglSurface = eglCreateWindowSurface(m_eglDisplay, config, m_nativeWindow, NULL);
     m_format = q_glFormatFromConfig(m_eglDisplay, config, window()->requestedFormat());
-    if (m_eglSurface == EGL_NO_SURFACE) {
+    if (Q_UNLIKELY(m_eglSurface == EGL_NO_SURFACE)) {
         EGLint error = eglGetError();
         eglTerminate(m_eglDisplay);
         qFatal("EGL Error : Could not create the egl surface: error = 0x%x\n", error);
diff --git a/src/plugins/platforms/android/qandroidplatformtheme.cpp b/src/plugins/platforms/android/qandroidplatformtheme.cpp
index 55bef1a1e8..949d31740a 100644
--- a/src/plugins/platforms/android/qandroidplatformtheme.cpp
+++ b/src/plugins/platforms/android/qandroidplatformtheme.cpp
@@ -203,12 +203,12 @@ QJsonObject AndroidStyle::loadStyleData()
 
     QJsonParseError error;
     QJsonDocument document = QJsonDocument::fromJson(f.readAll(), &error);
-    if (document.isNull()) {
+    if (Q_UNLIKELY(document.isNull())) {
         qCritical() << error.errorString();
         return QJsonObject();
     }
 
-    if (!document.isObject()) {
+    if (Q_UNLIKELY(!document.isObject())) {
         qCritical() << "Style.json does not contain a valid style.";
         return QJsonObject();
     }