X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FSupport%2FThreading.cpp;h=ca7f3f64aa37e37f3b7acbb815d0cba3b99bf4ff;hb=6c0e1e0fa658f4e7466c6787aedce992ece2db55;hp=a5876487e055890fcd0436f5137bb7c3c7ed1239;hpb=4c7ac18fc9e9af51ea6362871589c13263526d7a;p=oota-llvm.git

diff --git a/lib/Support/Threading.cpp b/lib/Support/Threading.cpp
index a5876487e05..ca7f3f64aa3 100644
--- a/lib/Support/Threading.cpp
+++ b/lib/Support/Threading.cpp
@@ -7,57 +7,106 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// 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/System/Atomic.h"
-#include "llvm/System/Mutex.h"
+#include "llvm/Config/config.h"
+#include "llvm/Support/Atomic.h"
+#include "llvm/Support/Mutex.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
+#if LLVM_ENABLE_THREADS != 0 && defined(HAVE_PTHREAD_H)
+#include <pthread.h>
+
+struct ThreadInfo {
+  void (*UserFn)(void *);
+  void *UserData;
+};
+static void *ExecuteOnThread_Dispatch(void *Arg) {
+  ThreadInfo *TI = reinterpret_cast<ThreadInfo*>(Arg);
+  TI->UserFn(TI->UserData);
+  return nullptr;
 }
 
-bool llvm::llvm_is_multithreaded() {
-  return multithreaded_mode;
+void llvm::llvm_execute_on_thread(void (*Fn)(void*), void *UserData,
+                                  unsigned RequestedStackSize) {
+  ThreadInfo Info = { Fn, UserData };
+  pthread_attr_t Attr;
+  pthread_t Thread;
+
+  // Construct the attributes object.
+  if (::pthread_attr_init(&Attr) != 0)
+    return;
+
+  // Set the requested stack size, if given.
+  if (RequestedStackSize != 0) {
+    if (::pthread_attr_setstacksize(&Attr, RequestedStackSize) != 0)
+      goto error;
+  }
+
+  // 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);
+
+ error:
+  ::pthread_attr_destroy(&Attr);
+}
+#elif LLVM_ENABLE_THREADS!=0 && defined(LLVM_ON_WIN32)
+#include "Windows/WindowsSupport.h"
+#include <process.h>
+
+struct ThreadInfo {
+  void (*func)(void*);
+  void *param;
+};
+
+static unsigned __stdcall ThreadCallback(void *param) {
+  struct ThreadInfo *info = reinterpret_cast<struct ThreadInfo *>(param);
+  info->func(info->param);
+
+  return 0;
 }
 
-void llvm::llvm_acquire_global_lock() {
-  if (multithreaded_mode) global_lock->acquire();
+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;
+  Fn(UserData);
 }
 
-void llvm::llvm_release_global_lock() {
-  if (multithreaded_mode) global_lock->release();
-}
\ No newline at end of file
+#endif