Remove some more code out into a separate CL.

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

diff --git a/lib/Support/Threading.cpp b/lib/Support/Threading.cpp
index 9d7ac6c18deb7db208265a7e116a0f0131486578..ff591aaa1d8fb08dc62f991a273df50e077d5718 100644 (file)
--- a/lib/Support/Threading.cpp
+++ b/lib/Support/Threading.cpp
@@ -7,7 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// This file implements llvm_start_multithreaded() and friends.
+// This file implements helper functions for running LLVM in a multi-threaded
+// environment.
 //
 //===----------------------------------------------------------------------===//
 
@@ -19,50 +20,19 @@
 
 using namespace llvm;
 
-static bool multithreaded_mode = false;
-
-static sys::Mutex* global_lock = 0;
+sys::Mutex& llvm::llvm_get_global_lock() {
+  static sys::Mutex global_lock;
+  return global_lock;
+}
 
-bool llvm::llvm_start_multithreaded() {
+bool llvm::llvm_is_multithreaded() {
 #if LLVM_ENABLE_THREADS != 0
-  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();
   return true;
 #else
   return false;
 #endif
 }
 
-void llvm::llvm_stop_multithreaded() {
-#if LLVM_ENABLE_THREADS != 0
-  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 LLVM_ENABLE_THREADS != 0 && defined(HAVE_PTHREAD_H)
 #include <pthread.h>
 
@@ -73,7 +43,7 @@ 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,
@@ -97,7 +67,7 @@ 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);