[lldb] NFC modernize codebase with modernize-use-nullptr

Summary:
NFC = [[ https://llvm.org/docs/Lexicon.html#nfc | Non functional change ]]

This commit is the result of modernizing the LLDB codebase by using
`nullptr` instread of `0` or `NULL`. See
https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-nullptr.html
for more information.

This is the command I ran and I to fix and format the code base:

```
run-clang-tidy.py \
	-header-filter='.*' \
	-checks='-*,modernize-use-nullptr' \
	-fix ~/dev/llvm-project/lldb/.* \
	-format \
	-style LLVM \
	-p ~/llvm-builds/debug-ninja-gcc
```

NOTE: There were also changes to `llvm/utils/unittest` but I did not
include them because I felt that maybe this library shall be updated in
isolation somehow.

NOTE: I know this is a rather large commit but it is a nobrainer in most
parts.

Reviewers: martong, espindola, shafik, #lldb, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: arsenm, jvesely, nhaehnle, hiraditya, JDevlieghere, teemperor, rnkovacs, emaste, kubamracek, nemanjai, ki.stfu, javed.absar, arichardson, kbarton, jrtc27, MaskRay, atanasyan, dexonsmith, arphaman, jfb, jsji, jdoerfert, lldb-commits, llvm-commits

Tags: #lldb, #llvm

Differential Revision: https://reviews.llvm.org/D61847

llvm-svn: 361484

5 files changed, 15 insertions, 14 deletions

diff --git a/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetItemInfoHandler.cpp b/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetItemInfoHandler.cpp
index 00b2826e1f0..c97eb98557a 100644
--- a/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetItemInfoHandler.cpp
+++ b/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetItemInfoHandler.cpp
@@ -143,7 +143,7 @@ lldb::addr_t AppleGetItemInfoHandler::SetupGetItemInfoFunction(
     // function:
 
     if (!m_get_item_info_impl_code) {
-      if (g_get_item_info_function_code != NULL) {
+      if (g_get_item_info_function_code != nullptr) {
         Status error;
         m_get_item_info_impl_code.reset(
             exe_ctx.GetTargetRef().GetUtilityFunctionForLanguage(
diff --git a/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetPendingItemsHandler.cpp b/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetPendingItemsHandler.cpp
index ddd3cb5d7cb..12fad7f561b 100644
--- a/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetPendingItemsHandler.cpp
+++ b/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetPendingItemsHandler.cpp
@@ -147,7 +147,7 @@ lldb::addr_t AppleGetPendingItemsHandler::SetupGetPendingItemsFunction(
     // First stage is to make the ClangUtility to hold our injected function:
 
     if (!m_get_pending_items_impl_code) {
-      if (g_get_pending_items_function_code != NULL) {
+      if (g_get_pending_items_function_code != nullptr) {
         Status error;
         m_get_pending_items_impl_code.reset(
             exe_ctx.GetTargetRef().GetUtilityFunctionForLanguage(
@@ -347,7 +347,7 @@ AppleGetPendingItemsHandler::GetPendingItems(Thread &thread, addr_t queue,
   options.SetIsForUtilityExpr(true);
   thread.CalculateExecutionContext(exe_ctx);
 
-  if (get_pending_items_caller == NULL) {
+  if (get_pending_items_caller == nullptr) {
     error.SetErrorString("Unable to compile function to call "
                          "__introspection_dispatch_queue_get_pending_items");
     return return_value;
diff --git a/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetQueuesHandler.cpp b/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetQueuesHandler.cpp
index 2b6c553dd43..e1dabae0d58 100644
--- a/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetQueuesHandler.cpp
+++ b/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetQueuesHandler.cpp
@@ -158,7 +158,7 @@ AppleGetQueuesHandler::SetupGetQueuesFunction(Thread &thread,
     // First stage is to make the ClangUtility to hold our injected function:
 
     if (!m_get_queues_impl_code_up) {
-      if (g_get_current_queues_function_code != NULL) {
+      if (g_get_current_queues_function_code != nullptr) {
         Status error;
         m_get_queues_impl_code_up.reset(
             exe_ctx.GetTargetRef().GetUtilityFunctionForLanguage(
@@ -335,7 +335,7 @@ AppleGetQueuesHandler::GetCurrentQueues(Thread &thread, addr_t page_to_free,
   FunctionCaller *get_queues_caller =
       m_get_queues_impl_code_up->GetFunctionCaller();
 
-  if (get_queues_caller == NULL) {
+  if (get_queues_caller == nullptr) {
     error.SetErrorString(
         "Unable to get caller for call __introspection_dispatch_get_queues");
     return return_value;
diff --git a/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetThreadItemInfoHandler.cpp b/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetThreadItemInfoHandler.cpp
index f409b674c53..7d0cbc0c100 100644
--- a/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetThreadItemInfoHandler.cpp
+++ b/lldb/source/Plugins/SystemRuntime/MacOSX/AppleGetThreadItemInfoHandler.cpp
@@ -154,7 +154,7 @@ lldb::addr_t AppleGetThreadItemInfoHandler::SetupGetThreadItemInfoFunction(
 
     if (!m_get_thread_item_info_impl_code) {
       Status error;
-      if (g_get_thread_item_info_function_code != NULL) {
+      if (g_get_thread_item_info_function_code != nullptr) {
         m_get_thread_item_info_impl_code.reset(
             exe_ctx.GetTargetRef().GetUtilityFunctionForLanguage(
                 g_get_thread_item_info_function_code, eLanguageTypeC,
diff --git a/lldb/source/Plugins/SystemRuntime/MacOSX/SystemRuntimeMacOSX.cpp b/lldb/source/Plugins/SystemRuntime/MacOSX/SystemRuntimeMacOSX.cpp
index 82be85699b2..91a60b17fc9 100644
--- a/lldb/source/Plugins/SystemRuntime/MacOSX/SystemRuntimeMacOSX.cpp
+++ b/lldb/source/Plugins/SystemRuntime/MacOSX/SystemRuntimeMacOSX.cpp
@@ -70,7 +70,7 @@ SystemRuntime *SystemRuntimeMacOSX::CreateInstance(Process *process) {
 
   if (create)
     return new SystemRuntimeMacOSX(process);
-  return NULL;
+  return nullptr;
 }
 
 // Constructor
@@ -106,7 +106,7 @@ void SystemRuntimeMacOSX::Clear(bool clear_process) {
     m_process->ClearBreakpointSiteByID(m_break_id);
 
   if (clear_process)
-    m_process = NULL;
+    m_process = nullptr;
   m_break_id = LLDB_INVALID_BREAK_ID;
 }
 
@@ -266,7 +266,7 @@ void SystemRuntimeMacOSX::ReadLibdispatchOffsetsAddress() {
 
   static ConstString g_dispatch_queue_offsets_symbol_name(
       "dispatch_queue_offsets");
-  const Symbol *dispatch_queue_offsets_symbol = NULL;
+  const Symbol *dispatch_queue_offsets_symbol = nullptr;
 
   // libdispatch symbols were in libSystem.B.dylib up through Mac OS X 10.6
   // ("Snow Leopard")
@@ -279,7 +279,7 @@ void SystemRuntimeMacOSX::ReadLibdispatchOffsetsAddress() {
 
   // libdispatch symbols are in their own dylib as of Mac OS X 10.7 ("Lion")
   // and later
-  if (dispatch_queue_offsets_symbol == NULL) {
+  if (dispatch_queue_offsets_symbol == nullptr) {
     ModuleSpec libdispatch_module_spec(FileSpec("libdispatch.dylib"));
     module_sp = m_process->GetTarget().GetImages().FindFirstModule(
         libdispatch_module_spec);
@@ -322,7 +322,7 @@ void SystemRuntimeMacOSX::ReadLibpthreadOffsetsAddress() {
 
   static ConstString g_libpthread_layout_offsets_symbol_name(
       "pthread_layout_offsets");
-  const Symbol *libpthread_layout_offsets_symbol = NULL;
+  const Symbol *libpthread_layout_offsets_symbol = nullptr;
 
   ModuleSpec libpthread_module_spec(FileSpec("libsystem_pthread.dylib"));
   ModuleSP module_sp(m_process->GetTarget().GetImages().FindFirstModule(
@@ -370,7 +370,7 @@ void SystemRuntimeMacOSX::ReadLibdispatchTSDIndexesAddress() {
 
   static ConstString g_libdispatch_tsd_indexes_symbol_name(
       "dispatch_tsd_indexes");
-  const Symbol *libdispatch_tsd_indexes_symbol = NULL;
+  const Symbol *libdispatch_tsd_indexes_symbol = nullptr;
 
   ModuleSpec libpthread_module_spec(FileSpec("libdispatch.dylib"));
   ModuleSP module_sp(m_process->GetTarget().GetImages().FindFirstModule(
@@ -726,7 +726,8 @@ void SystemRuntimeMacOSX::PopulateQueueList(
   for (ThreadSP thread_sp : m_process->Threads()) {
     if (thread_sp->GetAssociatedWithLibdispatchQueue() != eLazyBoolNo) {
       if (thread_sp->GetQueueID() != LLDB_INVALID_QUEUE_ID) {
-        if (queue_list.FindQueueByID(thread_sp->GetQueueID()).get() == NULL) {
+        if (queue_list.FindQueueByID(thread_sp->GetQueueID()).get() ==
+            nullptr) {
           QueueSP queue_sp(new Queue(m_process->shared_from_this(),
                                      thread_sp->GetQueueID(),
                                      thread_sp->GetQueueName()));
@@ -933,7 +934,7 @@ void SystemRuntimeMacOSX::PopulateQueuesUsingLibBTR(
       offset = start_of_this_item +
                m_lib_backtrace_recording_info.queue_info_data_offset;
       const char *queue_label = extractor.GetCStr(&offset);
-      if (queue_label == NULL)
+      if (queue_label == nullptr)
         queue_label = "";
 
       offset_t start_of_next_item = start_of_this_item + offset_to_next;