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>

1 files changed, 5 insertions, 5 deletions

diff --git a/src/plugins/platforms/qnx/qqnxvirtualkeyboardpps.cpp b/src/plugins/platforms/qnx/qqnxvirtualkeyboardpps.cpp
index 2c7a28e835..33e5cf2947 100644
--- a/src/plugins/platforms/qnx/qqnxvirtualkeyboardpps.cpp
+++ b/src/plugins/platforms/qnx/qqnxvirtualkeyboardpps.cpp
@@ -127,7 +127,7 @@ bool QQnxVirtualKeyboardPps::connect()
     }
 
     m_buffer = new char[ms_bufferSize];
-    if (!m_buffer) {
+    if (Q_UNLIKELY(!m_buffer)) {
         qCritical("QQnxVirtualKeyboard: Unable to allocate buffer of %d bytes. "
                   "Size is unavailable.",  ms_bufferSize);
         return false;
@@ -170,7 +170,7 @@ void QQnxVirtualKeyboardPps::ppsDataReady()
         return;
 
     // nread is the real space necessary, not the amount read.
-    if (static_cast<size_t>(nread) > ms_bufferSize - 1) {
+    if (Q_UNLIKELY(static_cast<size_t>(nread) > ms_bufferSize - 1)) {
         qCritical("QQnxVirtualKeyboard: Keyboard buffer size too short; need %u.", nread + 1);
         connect(); // reconnect
         return;
@@ -184,7 +184,7 @@ void QQnxVirtualKeyboardPps::ppsDataReady()
 #endif
 
     const char *value;
-    if (pps_decoder_get_string(m_decoder, "error", &value) == PPS_DECODER_OK) {
+    if (Q_UNLIKELY(pps_decoder_get_string(m_decoder, "error", &value) == PPS_DECODER_OK)) {
         qCritical("QQnxVirtualKeyboard: Keyboard PPS decoder error: %s", value ? value : "[null]");
         return;
     }
@@ -214,11 +214,11 @@ void QQnxVirtualKeyboardPps::handleKeyboardInfoMessage()
 {
     int newHeight = 0;
 
-    if (pps_decoder_push(m_decoder, "dat") != PPS_DECODER_OK) {
+    if (Q_UNLIKELY(pps_decoder_push(m_decoder, "dat") != PPS_DECODER_OK)) {
         qCritical("QQnxVirtualKeyboard: Keyboard PPS dat object not found");
         return;
     }
-    if (pps_decoder_get_int(m_decoder, "size", &newHeight) != PPS_DECODER_OK) {
+    if (Q_UNLIKELY(pps_decoder_get_int(m_decoder, "size", &newHeight) != PPS_DECODER_OK)) {
         qCritical("QQnxVirtualKeyboard: Keyboard PPS size field not found");
         return;
     }