[PGO] Convert InstrProfRecord based serialization methods to use common C methods

[oota-llvm.git] / lib / Support / Threading.cpp

diff --git a/lib/Support/Threading.cpp b/lib/Support/Threading.cpp
index 29579567ac6c19f7f919a5f8039f9efc23bddfe6..ca7f3f64aa37e37f3b7acbb815d0cba3b99bf4ff 100644 (file)
--- a/lib/Support/Threading.cpp
+++ b/lib/Support/Threading.cpp
@@ -7,63 +7,28 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// This file implements llvm_start_multithreaded() and friends.
+// This file defines helper functions for running LLVM in a multi-threaded
+// environment.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Support/Threading.h"
+#include "llvm/Config/config.h"
 #include "llvm/Support/Atomic.h"
 #include "llvm/Support/Mutex.h"
-#include "llvm/Config/config.h"
 #include <cassert>
 
 using namespace llvm;
 
-static bool multithreaded_mode = false;
-
-static sys::Mutex* global_lock = 0;
-
-bool llvm::llvm_start_multithreaded() {
-#ifdef LLVM_MULTITHREADED
-  assert(!multithreaded_mode && "Already multithreaded!");
-  multithreaded_mode = true;
-  global_lock = new sys::Mutex(true);
-
-  // We fence here to ensure that all initialization is complete BEFORE we
-  // return from llvm_start_multithreaded().
-  sys::MemoryFence();
+bool llvm::llvm_is_multithreaded() {
+#if LLVM_ENABLE_THREADS != 0
   return true;
 #else
   return false;
 #endif
 }
 
-void llvm::llvm_stop_multithreaded() {
-#ifdef LLVM_MULTITHREADED
-  assert(multithreaded_mode && "Not currently multithreaded!");
-
-  // We fence here to insure that all threaded operations are complete BEFORE we
-  // return from llvm_stop_multithreaded().
-  sys::MemoryFence();
-
-  multithreaded_mode = false;
-  delete global_lock;
-#endif
-}
-
-bool llvm::llvm_is_multithreaded() {
-  return multithreaded_mode;
-}
-
-void llvm::llvm_acquire_global_lock() {
-  if (multithreaded_mode) global_lock->acquire();
-}
-
-void llvm::llvm_release_global_lock() {
-  if (multithreaded_mode) global_lock->release();
-}
-
-#if defined(LLVM_MULTITHREADED) && defined(HAVE_PTHREAD_H)
+#if LLVM_ENABLE_THREADS != 0 && defined(HAVE_PTHREAD_H)
 #include <pthread.h>
 
 struct ThreadInfo {
@@ -73,7 +38,7 @@ struct ThreadInfo {
 static void *ExecuteOnThread_Dispatch(void *Arg) {
   ThreadInfo *TI = reinterpret_cast<ThreadInfo*>(Arg);
   TI->UserFn(TI->UserData);
-  return 0;
+  return nullptr;
 }
 
 void llvm::llvm_execute_on_thread(void (*Fn)(void*), void *UserData,
@@ -97,16 +62,47 @@ void llvm::llvm_execute_on_thread(void (*Fn)(void*), void *UserData,
     goto error;
 
   // Wait for the thread and clean up.
-  ::pthread_join(Thread, 0);
+  ::pthread_join(Thread, nullptr);
 
  error:
   ::pthread_attr_destroy(&Attr);
 }
+#elif LLVM_ENABLE_THREADS!=0 && defined(LLVM_ON_WIN32)
+#include "Windows/WindowsSupport.h"
+#include <process.h>
 
-#else
+struct ThreadInfo {
+  void (*func)(void*);
+  void *param;
+};
 
-// No non-pthread implementation, currently.
+static unsigned __stdcall ThreadCallback(void *param) {
+  struct ThreadInfo *info = reinterpret_cast<struct ThreadInfo *>(param);
+  info->func(info->param);
 
+  return 0;
+}
+
+void llvm::llvm_execute_on_thread(void (*Fn)(void*), void *UserData,
+                                  unsigned RequestedStackSize) {
+  struct ThreadInfo param = { Fn, UserData };
+
+  HANDLE hThread = (HANDLE)::_beginthreadex(NULL,
+                                            RequestedStackSize, ThreadCallback,
+                                            &param, 0, NULL);
+
+  if (hThread) {
+    // We actually don't care whether the wait succeeds or fails, in
+    // the same way we don't care whether the pthread_join call succeeds
+    // or fails.  There's not much we could do if this were to fail. But
+    // on success, this call will wait until the thread finishes executing
+    // before returning.
+    (void)::WaitForSingleObject(hThread, INFINITE);
+    ::CloseHandle(hThread);
+  }
+}
+#else
+// Support for non-Win32, non-pthread implementation.
 void llvm::llvm_execute_on_thread(void (*Fn)(void*), void *UserData,
                                   unsigned RequestedStackSize) {
   (void) RequestedStackSize;