1 files changed, 210 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Support/PrettyStackTrace.cpp b/contrib/llvm/lib/Support/PrettyStackTrace.cpp
new file mode 100644
index 000000000000..f5b6e6f3652d
--- /dev/null
+++ b/contrib/llvm/lib/Support/PrettyStackTrace.cpp
@@ -0,0 +1,210 @@
+//===- PrettyStackTrace.cpp - Pretty Crash Handling -----------------------===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+//
+// This file defines some helpful functions for dealing with the possibility of
+// Unix signals occurring while your program is running.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/PrettyStackTrace.h"
+#include "llvm-c/ErrorHandling.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/Config/config.h" // Get autoconf configuration settings
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Signals.h"
+#include "llvm/Support/Watchdog.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include <cstdarg>
+#include <cstdio>
+#include <tuple>
+
+#ifdef HAVE_CRASHREPORTERCLIENT_H
+#include <CrashReporterClient.h>
+#endif
+
+using namespace llvm;
+
+// If backtrace support is not enabled, compile out support for pretty stack
+// traces.  This has the secondary effect of not requiring thread local storage
+// when backtrace support is disabled.
+#if defined(HAVE_BACKTRACE) && ENABLE_BACKTRACES
+
+// We need a thread local pointer to manage the stack of our stack trace
+// objects, but we *really* cannot tolerate destructors running and do not want
+// to pay any overhead of synchronizing. As a consequence, we use a raw
+// thread-local variable.
+static LLVM_THREAD_LOCAL PrettyStackTraceEntry *PrettyStackTraceHead = nullptr;
+
+namespace llvm {
+PrettyStackTraceEntry *ReverseStackTrace(PrettyStackTraceEntry *Head) {
+  PrettyStackTraceEntry *Prev = nullptr;
+  while (Head)
+    std::tie(Prev, Head, Head->NextEntry) =
+        std::make_tuple(Head, Head->NextEntry, Prev);
+  return Prev;
+}
+}
+
+static void PrintStack(raw_ostream &OS) {
+  // Print out the stack in reverse order. To avoid recursion (which is likely
+  // to fail if we crashed due to stack overflow), we do an up-front pass to
+  // reverse the stack, then print it, then reverse it again.
+  unsigned ID = 0;
+  PrettyStackTraceEntry *ReversedStack =
+      llvm::ReverseStackTrace(PrettyStackTraceHead);
+  for (const PrettyStackTraceEntry *Entry = ReversedStack; Entry;
+       Entry = Entry->getNextEntry()) {
+    OS << ID++ << ".\t";
+    sys::Watchdog W(5);
+    Entry->print(OS);
+  }
+  llvm::ReverseStackTrace(ReversedStack);
+}
+
+/// PrintCurStackTrace - Print the current stack trace to the specified stream.
+static void PrintCurStackTrace(raw_ostream &OS) {
+  // Don't print an empty trace.
+  if (!PrettyStackTraceHead) return;
+  
+  // If there are pretty stack frames registered, walk and emit them.
+  OS << "Stack dump:\n";
+  
+  PrintStack(OS);
+  OS.flush();
+}
+
+// Integrate with crash reporter libraries.
+#if defined (__APPLE__) && defined(HAVE_CRASHREPORTERCLIENT_H)
+//  If any clients of llvm try to link to libCrashReporterClient.a themselves,
+//  only one crash info struct will be used.
+extern "C" {
+CRASH_REPORTER_CLIENT_HIDDEN 
+struct crashreporter_annotations_t gCRAnnotations 
+        __attribute__((section("__DATA," CRASHREPORTER_ANNOTATIONS_SECTION))) 
+#if CRASHREPORTER_ANNOTATIONS_VERSION < 5
+        = { CRASHREPORTER_ANNOTATIONS_VERSION, 0, 0, 0, 0, 0, 0 };
+#else
+        = { CRASHREPORTER_ANNOTATIONS_VERSION, 0, 0, 0, 0, 0, 0, 0 };
+#endif
+}
+#elif defined(__APPLE__) && HAVE_CRASHREPORTER_INFO
+extern "C" const char *__crashreporter_info__
+    __attribute__((visibility("hidden"))) = 0;
+asm(".desc ___crashreporter_info__, 0x10");
+#endif
+
+/// CrashHandler - This callback is run if a fatal signal is delivered to the
+/// process, it prints the pretty stack trace.
+static void CrashHandler(void *) {
+#ifndef __APPLE__
+  // On non-apple systems, just emit the crash stack trace to stderr.
+  PrintCurStackTrace(errs());
+#else
+  // Otherwise, emit to a smallvector of chars, send *that* to stderr, but also
+  // put it into __crashreporter_info__.
+  SmallString<2048> TmpStr;
+  {
+    raw_svector_ostream Stream(TmpStr);
+    PrintCurStackTrace(Stream);
+  }
+  
+  if (!TmpStr.empty()) {
+#ifdef HAVE_CRASHREPORTERCLIENT_H
+    // Cast to void to avoid warning.
+    (void)CRSetCrashLogMessage(TmpStr.c_str());
+#elif HAVE_CRASHREPORTER_INFO 
+    __crashreporter_info__ = strdup(TmpStr.c_str());
+#endif
+    errs() << TmpStr.str();
+  }
+  
+#endif
+}
+
+// defined(HAVE_BACKTRACE) && ENABLE_BACKTRACES
+#endif
+
+PrettyStackTraceEntry::PrettyStackTraceEntry() {
+#if defined(HAVE_BACKTRACE) && ENABLE_BACKTRACES
+  // Link ourselves.
+  NextEntry = PrettyStackTraceHead;
+  PrettyStackTraceHead = this;
+#endif
+}
+
+PrettyStackTraceEntry::~PrettyStackTraceEntry() {
+#if defined(HAVE_BACKTRACE) && ENABLE_BACKTRACES
+  assert(PrettyStackTraceHead == this &&
+         "Pretty stack trace entry destruction is out of order");
+  PrettyStackTraceHead = NextEntry;
+#endif
+}
+
+void PrettyStackTraceString::print(raw_ostream &OS) const { OS << Str << "\n"; }
+
+PrettyStackTraceFormat::PrettyStackTraceFormat(const char *Format, ...) {
+  va_list AP;
+  va_start(AP, Format);
+  const int SizeOrError = vsnprintf(nullptr, 0, Format, AP);
+  va_end(AP);
+  if (SizeOrError < 0) {
+    return;
+  }
+
+  const int Size = SizeOrError + 1; // '\0'
+  Str.resize(Size);
+  va_start(AP, Format);
+  vsnprintf(Str.data(), Size, Format, AP);
+  va_end(AP);
+}
+
+void PrettyStackTraceFormat::print(raw_ostream &OS) const { OS << Str << "\n"; }
+
+void PrettyStackTraceProgram::print(raw_ostream &OS) const {
+  OS << "Program arguments: ";
+  // Print the argument list.
+  for (unsigned i = 0, e = ArgC; i != e; ++i)
+    OS << ArgV[i] << ' ';
+  OS << '\n';
+}
+
+#if defined(HAVE_BACKTRACE) && ENABLE_BACKTRACES
+static bool RegisterCrashPrinter() {
+  sys::AddSignalHandler(CrashHandler, nullptr);
+  return false;
+}
+#endif
+
+void llvm::EnablePrettyStackTrace() {
+#if defined(HAVE_BACKTRACE) && ENABLE_BACKTRACES
+  // The first time this is called, we register the crash printer.
+  static bool HandlerRegistered = RegisterCrashPrinter();
+  (void)HandlerRegistered;
+#endif
+}
+
+const void *llvm::SavePrettyStackState() {
+#if defined(HAVE_BACKTRACE) && ENABLE_BACKTRACES
+  return PrettyStackTraceHead;
+#else
+  return nullptr;
+#endif
+}
+
+void llvm::RestorePrettyStackState(const void *Top) {
+#if defined(HAVE_BACKTRACE) && ENABLE_BACKTRACES
+  PrettyStackTraceHead =
+      static_cast<PrettyStackTraceEntry *>(const_cast<void *>(Top));
+#endif
+}
+
+void LLVMEnablePrettyStackTrace() {
+  EnablePrettyStackTrace();
+}