2 files changed, 46 insertions, 26 deletions

diff --git a/llvm/lib/Support/Unix/Threading.inc b/llvm/lib/Support/Unix/Threading.inc
index ed9a9656305..afb887fc109 100644
--- a/llvm/lib/Support/Unix/Threading.inc
+++ b/llvm/lib/Support/Unix/Threading.inc
@@ -10,6 +10,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "Unix.h"
+#include "llvm/ADT/ScopeExit.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/Twine.h"
 
@@ -40,47 +42,56 @@
 #include <unistd.h>      // For syscall()
 #endif
 
-namespace {
-  struct ThreadInfo {
-    void(*UserFn)(void *);
-    void *UserData;
-  };
+static void *threadFuncSync(void *Arg) {
+  SyncThreadInfo *TI = static_cast<SyncThreadInfo *>(Arg);
+  TI->UserFn(TI->UserData);
+  return nullptr;
 }
 
-static void *ExecuteOnThread_Dispatch(void *Arg) {
-  ThreadInfo *TI = reinterpret_cast<ThreadInfo*>(Arg);
-  TI->UserFn(TI->UserData);
+static void *threadFuncAsync(void *Arg) {
+  std::unique_ptr<AsyncThreadInfo> Info(static_cast<AsyncThreadInfo *>(Arg));
+  (*Info)();
   return nullptr;
 }
 
-void llvm::llvm_execute_on_thread(void(*Fn)(void*), void *UserData,
-  unsigned RequestedStackSize) {
-  ThreadInfo Info = { Fn, UserData };
-  pthread_attr_t Attr;
-  pthread_t Thread;
+static void
+llvm_execute_on_thread_impl(void *(*ThreadFunc)(void *), void *Arg,
+                            llvm::Optional<unsigned> StackSizeInBytes,
+                            JoiningPolicy JP) {
+  int errnum;
 
   // Construct the attributes object.
-  if (::pthread_attr_init(&Attr) != 0)
-    return;
+  pthread_attr_t Attr;
+  if ((errnum = ::pthread_attr_init(&Attr)) != 0) {
+    ReportErrnumFatal("pthread_attr_init failed", errnum);
+  }
+
+  auto AttrGuard = llvm::make_scope_exit([&] {
+    if ((errnum = ::pthread_attr_destroy(&Attr)) != 0) {
+      ReportErrnumFatal("pthread_attr_destroy failed", errnum);
+    }
+  });
 
   // Set the requested stack size, if given.
-  if (RequestedStackSize != 0) {
-    if (::pthread_attr_setstacksize(&Attr, RequestedStackSize) != 0)
-      goto error;
+  if (StackSizeInBytes) {
+    if ((errnum = ::pthread_attr_setstacksize(&Attr, *StackSizeInBytes)) != 0) {
+      ReportErrnumFatal("pthread_attr_setstacksize failed", errnum);
+    }
   }
 
   // Construct and execute the thread.
-  if (::pthread_create(&Thread, &Attr, ExecuteOnThread_Dispatch, &Info) != 0)
-    goto error;
-
-  // Wait for the thread and clean up.
-  ::pthread_join(Thread, nullptr);
+  pthread_t Thread;
+  if ((errnum = ::pthread_create(&Thread, &Attr, ThreadFunc, Arg)) != 0)
+    ReportErrnumFatal("pthread_create failed", errnum);
 
-error:
-  ::pthread_attr_destroy(&Attr);
+  if (JP == JoiningPolicy::Join) {
+    // Wait for the thread
+    if ((errnum = ::pthread_join(Thread, nullptr)) != 0) {
+      ReportErrnumFatal("pthread_join failed", errnum);
+    }
+  }
 }
 
-
 uint64_t llvm::get_threadid() {
 #if defined(__APPLE__)
   // Calling "mach_thread_self()" bumps the reference count on the thread
diff --git a/llvm/lib/Support/Unix/Unix.h b/llvm/lib/Support/Unix/Unix.h
index 86309b0567f..1fc9a414f74 100644
--- a/llvm/lib/Support/Unix/Unix.h
+++ b/llvm/lib/Support/Unix/Unix.h
@@ -21,6 +21,7 @@
 #include "llvm/Config/config.h"
 #include "llvm/Support/Chrono.h"
 #include "llvm/Support/Errno.h"
+#include "llvm/Support/ErrorHandling.h"
 #include <algorithm>
 #include <assert.h>
 #include <cerrno>
@@ -69,6 +70,14 @@ static inline bool MakeErrMsg(
   return true;
 }
 
+// Include StrError(errnum) in a fatal error message.
+LLVM_ATTRIBUTE_NORETURN static inline void ReportErrnumFatal(const char *Msg,
+                                                             int errnum) {
+  std::string ErrMsg;
+  MakeErrMsg(&ErrMsg, Msg, errnum);
+  llvm::report_fatal_error(ErrMsg);
+}
+
 namespace llvm {
 namespace sys {