WebAssembly: update expected failures, more assert got resolved.
[oota-llvm.git] / lib / Support / CrashRecoveryContext.cpp
index 614980f718a54417d6300b9227b203d97e713111..3f4ef9da48f17c8995523b31fdae8834164ad6c5 100644 (file)
@@ -8,13 +8,11 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Support/CrashRecoveryContext.h"
-#include "llvm/ADT/SmallString.h"
 #include "llvm/Config/config.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/ManagedStatic.h"
 #include "llvm/Support/Mutex.h"
 #include "llvm/Support/ThreadLocal.h"
-#include <cstdio>
 #include <setjmp.h>
 using namespace llvm;
 
@@ -22,9 +20,16 @@ namespace {
 
 struct CrashRecoveryContextImpl;
 
-static ManagedStatic<sys::ThreadLocal<const CrashRecoveryContextImpl> > CurrentContext;
+static ManagedStatic<
+    sys::ThreadLocal<const CrashRecoveryContextImpl> > CurrentContext;
 
 struct CrashRecoveryContextImpl {
+  // When threads are disabled, this links up all active
+  // CrashRecoveryContextImpls.  When threads are enabled there's one thread
+  // per CrashRecoveryContext and CurrentContext is a thread-local, so only one
+  // CrashRecoveryContextImpl is active per thread and this is always null.
+  const CrashRecoveryContextImpl *Next;
+
   CrashRecoveryContext *CRC;
   std::string Backtrace;
   ::jmp_buf JumpBuffer;
@@ -35,21 +40,26 @@ public:
   CrashRecoveryContextImpl(CrashRecoveryContext *CRC) : CRC(CRC),
                                                         Failed(false),
                                                         SwitchedThread(false) {
+    Next = CurrentContext->get();
     CurrentContext->set(this);
   }
   ~CrashRecoveryContextImpl() {
     if (!SwitchedThread)
-      CurrentContext->erase();
+      CurrentContext->set(Next);
   }
 
   /// \brief Called when the separate crash-recovery thread was finished, to
   /// indicate that we don't need to clear the thread-local CurrentContext.
-  void setSwitchedThread() { SwitchedThread = true; }
+  void setSwitchedThread() { 
+#if defined(LLVM_ENABLE_THREADS) && LLVM_ENABLE_THREADS != 0
+    SwitchedThread = true;
+#endif
+  }
 
   void HandleCrash() {
     // Eliminate the current context entry, to avoid re-entering in case the
     // cleanup code crashes.
-    CurrentContext->erase();
+    CurrentContext->set(Next);
 
     assert(!Failed && "Crash recovery context already failed!");
     Failed = true;
@@ -66,7 +76,7 @@ public:
 static ManagedStatic<sys::Mutex> gCrashRecoveryContextMutex;
 static bool gCrashRecoveryEnabled = false;
 
-static ManagedStatic<sys::ThreadLocal<const CrashRecoveryContextCleanup> >
+static ManagedStatic<sys::ThreadLocal<const CrashRecoveryContext>>
        tlIsRecoveringFromCrash;
 
 CrashRecoveryContextCleanup::~CrashRecoveryContextCleanup() {}
@@ -74,7 +84,8 @@ CrashRecoveryContextCleanup::~CrashRecoveryContextCleanup() {}
 CrashRecoveryContext::~CrashRecoveryContext() {
   // Reclaim registered resources.
   CrashRecoveryContextCleanup *i = head;
-  tlIsRecoveringFromCrash->set(head);
+  const CrashRecoveryContext *PC = tlIsRecoveringFromCrash->get();
+  tlIsRecoveringFromCrash->set(this);
   while (i) {
     CrashRecoveryContextCleanup *tmp = i;
     i = tmp->next;
@@ -82,23 +93,23 @@ CrashRecoveryContext::~CrashRecoveryContext() {
     tmp->recoverResources();
     delete tmp;
   }
-  tlIsRecoveringFromCrash->erase();
+  tlIsRecoveringFromCrash->set(PC);
   
   CrashRecoveryContextImpl *CRCI = (CrashRecoveryContextImpl *) Impl;
   delete CRCI;
 }
 
 bool CrashRecoveryContext::isRecoveringFromCrash() {
-  return tlIsRecoveringFromCrash->get() != 0;
+  return tlIsRecoveringFromCrash->get() != nullptr;
 }
 
 CrashRecoveryContext *CrashRecoveryContext::GetCurrent() {
   if (!gCrashRecoveryEnabled)
-    return 0;
+    return nullptr;
 
   const CrashRecoveryContextImpl *CRCI = CurrentContext->get();
   if (!CRCI)
-    return 0;
+    return nullptr;
 
   return CRCI->CRC;
 }
@@ -120,7 +131,7 @@ CrashRecoveryContext::unregisterCleanup(CrashRecoveryContextCleanup *cleanup) {
   if (cleanup == head) {
     head = cleanup->next;
     if (head)
-      head->prev = 0;
+      head->prev = nullptr;
   }
   else {
     cleanup->prev->next = cleanup->next;
@@ -231,8 +242,9 @@ void CrashRecoveryContext::Disable() {
 
 #include <signal.h>
 
-static const int Signals[] = { SIGABRT, SIGBUS, SIGFPE, SIGILL, SIGSEGV, SIGTRAP };
-static const unsigned NumSignals = sizeof(Signals) / sizeof(Signals[0]);
+static const int Signals[] =
+    { SIGABRT, SIGBUS, SIGFPE, SIGILL, SIGSEGV, SIGTRAP };
+static const unsigned NumSignals = array_lengthof(Signals);
 static struct sigaction PrevActions[NumSignals];
 
 static void CrashRecoverySignalHandler(int Signal) {
@@ -261,7 +273,7 @@ static void CrashRecoverySignalHandler(int Signal) {
   sigset_t SigMask;
   sigemptyset(&SigMask);
   sigaddset(&SigMask, Signal);
-  sigprocmask(SIG_UNBLOCK, &SigMask, 0);
+  sigprocmask(SIG_UNBLOCK, &SigMask, nullptr);
 
   if (CRCI)
     const_cast<CrashRecoveryContextImpl*>(CRCI)->HandleCrash();
@@ -296,16 +308,12 @@ void CrashRecoveryContext::Disable() {
 
   // Restore the previous signal handlers.
   for (unsigned i = 0; i != NumSignals; ++i)
-    sigaction(Signals[i], &PrevActions[i], 0);
+    sigaction(Signals[i], &PrevActions[i], nullptr);
 }
 
 #endif
 
-bool CrashRecoveryContext::RunSafely(void (*Fn)(void*), void *UserData) {
-  return RunSafely([&]() { Fn(UserData); });
-}
-
-bool CrashRecoveryContext::RunSafely(std::function<void()> Fn) {
+bool CrashRecoveryContext::RunSafely(function_ref<void()> Fn) {
   // If crash recovery is disabled, do nothing.
   if (gCrashRecoveryEnabled) {
     assert(!Impl && "Crash recovery context already initialized!");
@@ -334,17 +342,26 @@ const std::string &CrashRecoveryContext::getBacktrace() const {
   return CRC->Backtrace;
 }
 
-//
+// FIXME: Portability.
+static void setThreadBackgroundPriority() {
+#ifdef __APPLE__
+  setpriority(PRIO_DARWIN_THREAD, 0, PRIO_DARWIN_BG);
+#endif
+}
 
-bool CrashRecoveryContext::RunSafelyOnThread(void (*Fn)(void*), void *UserData,
-                                             unsigned RequestedStackSize) {
-  return RunSafelyOnThread([&]() { Fn(UserData); }, RequestedStackSize);
+static bool hasThreadBackgroundPriority() {
+#ifdef __APPLE__
+  return getpriority(PRIO_DARWIN_THREAD, 0) == 1;
+#else
+  return false;
+#endif
 }
 
 namespace {
 struct RunSafelyOnThreadInfo {
-  std::function<void()> Fn;
+  function_ref<void()> Fn;
   CrashRecoveryContext *CRC;
+  bool UseBackgroundPriority;
   bool Result;
 };
 }
@@ -352,12 +369,16 @@ struct RunSafelyOnThreadInfo {
 static void RunSafelyOnThread_Dispatch(void *UserData) {
   RunSafelyOnThreadInfo *Info =
     reinterpret_cast<RunSafelyOnThreadInfo*>(UserData);
+
+  if (Info->UseBackgroundPriority)
+    setThreadBackgroundPriority();
+
   Info->Result = Info->CRC->RunSafely(Info->Fn);
 }
-
-bool CrashRecoveryContext::RunSafelyOnThread(std::function<void()> Fn,
+bool CrashRecoveryContext::RunSafelyOnThread(function_ref<void()> Fn,
                                              unsigned RequestedStackSize) {
-  RunSafelyOnThreadInfo Info = { Fn, this, false };
+  bool UseBackgroundPriority = hasThreadBackgroundPriority();
+  RunSafelyOnThreadInfo Info = { Fn, this, UseBackgroundPriority, false };
   llvm_execute_on_thread(RunSafelyOnThread_Dispatch, &Info, RequestedStackSize);
   if (CrashRecoveryContextImpl *CRC = (CrashRecoveryContextImpl *)Impl)
     CRC->setSwitchedThread();