Merge llvm trunk r366426, resolve conflicts, and update FREEBSD-Xlist.

1 files changed, 58 insertions, 23 deletions

diff --git a/contrib/llvm/lib/Support/Unix/Signals.inc b/contrib/llvm/lib/Support/Unix/Signals.inc
index ad88d5e96906..634c16aa36c7 100644
--- a/contrib/llvm/lib/Support/Unix/Signals.inc
+++ b/contrib/llvm/lib/Support/Unix/Signals.inc
@@ -1,9 +1,8 @@
 //===- Signals.cpp - Generic Unix Signals Implementation -----*- C++ -*-===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
@@ -43,6 +42,7 @@
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Mutex.h"
 #include "llvm/Support/Program.h"
+#include "llvm/Support/SaveAndRestore.h"
 #include "llvm/Support/UniqueLock.h"
 #include "llvm/Support/raw_ostream.h"
 #include <algorithm>
@@ -81,10 +81,13 @@
 using namespace llvm;
 
 static RETSIGTYPE SignalHandler(int Sig);  // defined below.
+static RETSIGTYPE InfoSignalHandler(int Sig);  // defined below.
 
+using SignalHandlerFunctionType = void (*)();
 /// The function to call if ctrl-c is pressed.
-using InterruptFunctionType = void (*)();
-static std::atomic<InterruptFunctionType> InterruptFunction =
+static std::atomic<SignalHandlerFunctionType> InterruptFunction =
+    ATOMIC_VAR_INIT(nullptr);
+static std::atomic<SignalHandlerFunctionType> InfoSignalFunction =
     ATOMIC_VAR_INIT(nullptr);
 
 namespace {
@@ -200,15 +203,15 @@ struct FilesToRemoveCleanup {
 
 static StringRef Argv0;
 
-// Signals that represent requested termination. There's no bug or failure, or
-// if there is, it's not our direct responsibility. For whatever reason, our
-// continued execution is no longer desirable.
+/// Signals that represent requested termination. There's no bug or failure, or
+/// if there is, it's not our direct responsibility. For whatever reason, our
+/// continued execution is no longer desirable.
 static const int IntSigs[] = {
-  SIGHUP, SIGINT, SIGPIPE, SIGTERM, SIGUSR1, SIGUSR2
+  SIGHUP, SIGINT, SIGPIPE, SIGTERM, SIGUSR2
 };
 
-// Signals that represent that we have a bug, and our prompt termination has
-// been ordered.
+/// Signals that represent that we have a bug, and our prompt termination has
+/// been ordered.
 static const int KillSigs[] = {
   SIGILL, SIGTRAP, SIGABRT, SIGFPE, SIGBUS, SIGSEGV, SIGQUIT
 #ifdef SIGSYS
@@ -225,11 +228,24 @@ static const int KillSigs[] = {
 #endif
 };
 
+/// Signals that represent requests for status.
+static const int InfoSigs[] = {
+  SIGUSR1
+#ifdef SIGINFO
+  , SIGINFO
+#endif
+};
+
+static const size_t NumSigs =
+    array_lengthof(IntSigs) + array_lengthof(KillSigs) +
+    array_lengthof(InfoSigs);
+
+
 static std::atomic<unsigned> NumRegisteredSignals = ATOMIC_VAR_INIT(0);
 static struct {
   struct sigaction SA;
   int SigNo;
-} RegisteredSignalInfo[array_lengthof(IntSigs) + array_lengthof(KillSigs)];
+} RegisteredSignalInfo[NumSigs];
 
 #if defined(HAVE_SIGALTSTACK)
 // Hold onto both the old and new alternate signal stack so that it's not
@@ -277,15 +293,24 @@ static void RegisterHandlers() { // Not signal-safe.
   // be able to reliably handle signals due to stack overflow.
   CreateSigAltStack();
 
-  auto registerHandler = [&](int Signal) {
+  enum class SignalKind { IsKill, IsInfo };
+  auto registerHandler = [&](int Signal, SignalKind Kind) {
     unsigned Index = NumRegisteredSignals.load();
     assert(Index < array_lengthof(RegisteredSignalInfo) &&
            "Out of space for signal handlers!");
 
     struct sigaction NewHandler;
 
-    NewHandler.sa_handler = SignalHandler;
-    NewHandler.sa_flags = SA_NODEFER | SA_RESETHAND | SA_ONSTACK;
+    switch (Kind) {
+    case SignalKind::IsKill:
+      NewHandler.sa_handler = SignalHandler;
+      NewHandler.sa_flags = SA_NODEFER | SA_RESETHAND | SA_ONSTACK;
+      break;
+    case SignalKind::IsInfo:
+      NewHandler.sa_handler = InfoSignalHandler;
+      NewHandler.sa_flags = SA_ONSTACK;
+      break;
+    }
     sigemptyset(&NewHandler.sa_mask);
 
     // Install the new handler, save the old one in RegisteredSignalInfo.
@@ -295,9 +320,11 @@ static void RegisterHandlers() { // Not signal-safe.
   };
 
   for (auto S : IntSigs)
-    registerHandler(S);
+    registerHandler(S, SignalKind::IsKill);
   for (auto S : KillSigs)
-    registerHandler(S);
+    registerHandler(S, SignalKind::IsKill);
+  for (auto S : InfoSigs)
+    registerHandler(S, SignalKind::IsInfo);
 }
 
 static void UnregisterHandlers() {
@@ -357,6 +384,12 @@ static RETSIGTYPE SignalHandler(int Sig) {
 #endif
 }
 
+static RETSIGTYPE InfoSignalHandler(int Sig) {
+  SaveAndRestore<int> SaveErrnoDuringASignalHandler(errno);
+  if (SignalHandlerFunctionType CurrentInfoFunction = InfoSignalFunction)
+    CurrentInfoFunction();
+}
+
 void llvm::sys::RunInterruptHandlers() {
   RemoveFilesToRemove();
 }
@@ -366,6 +399,11 @@ void llvm::sys::SetInterruptFunction(void (*IF)()) {
   RegisterHandlers();
 }
 
+void llvm::sys::SetInfoSignalFunction(void (*Handler)()) {
+  InfoSignalFunction.exchange(Handler);
+  RegisterHandlers();
+}
+
 // The public API
 bool llvm::sys::RemoveFileOnSignal(StringRef Filename,
                                    std::string* ErrMsg) {
@@ -540,11 +578,8 @@ void llvm::sys::PrintStackTrace(raw_ostream &OS) {
       else    OS << d;
       free(d);
 
-      // FIXME: When we move to C++11, use %t length modifier. It's not in
-      // C++03 and causes gcc to issue warnings. Losing the upper 32 bits of
-      // the stack offset for a stack dump isn't likely to cause any problems.
-      OS << format(" + %u",(unsigned)((char*)StackTrace[i]-
-                                      (char*)dlinfo.dli_saddr));
+      OS << format(" + %tu", (static_cast<const char*>(StackTrace[i])-
+                              static_cast<const char*>(dlinfo.dli_saddr)));
     }
     OS << '\n';
   }