2006-09-28 00:31:55 +00:00
|
|
|
//===-- ManagedStatic.cpp - Static Global wrapper -------------------------===//
|
|
|
|
//
|
|
|
|
// The LLVM Compiler Infrastructure
|
|
|
|
//
|
2007-12-29 20:36:04 +00:00
|
|
|
// This file is distributed under the University of Illinois Open Source
|
|
|
|
// License. See LICENSE.TXT for details.
|
2006-09-28 00:31:55 +00:00
|
|
|
//
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
//
|
|
|
|
// This file implements the ManagedStatic class and llvm_shutdown().
|
|
|
|
//
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
|
|
|
|
#include "llvm/Support/ManagedStatic.h"
|
2009-05-20 00:39:20 +00:00
|
|
|
#include "llvm/Config/config.h"
|
2014-03-03 18:02:34 +00:00
|
|
|
#include "llvm/Support/Atomic.h"
|
2006-09-28 00:31:55 +00:00
|
|
|
#include <cassert>
|
2014-06-19 16:17:42 +00:00
|
|
|
#include <mutex>
|
2006-09-28 00:31:55 +00:00
|
|
|
using namespace llvm;
|
|
|
|
|
2014-04-07 04:17:22 +00:00
|
|
|
static const ManagedStaticBase *StaticList = nullptr;
|
2006-09-28 00:31:55 +00:00
|
|
|
|
2014-06-19 16:17:42 +00:00
|
|
|
// ManagedStatics can get created during execution of static constructors. As a
|
|
|
|
// result, we cannot use a global static std::mutex object for the lock since it
|
|
|
|
// may not have been constructed. Instead, we do a call-once initialization of
|
|
|
|
// a pointer to a mutex.
|
|
|
|
static std::once_flag MutexInitializationFlag;
|
|
|
|
static std::recursive_mutex* ManagedStaticMutex = nullptr;
|
|
|
|
|
|
|
|
// Not all supported platforms (in particular VS2012) have thread-safe function
|
|
|
|
// static initialization, so roll our own.
|
|
|
|
static std::recursive_mutex& GetManagedStaticMutex() {
|
|
|
|
std::call_once(MutexInitializationFlag,
|
|
|
|
[]() { ManagedStaticMutex = new std::recursive_mutex(); } );
|
|
|
|
|
|
|
|
return *ManagedStaticMutex;
|
|
|
|
}
|
|
|
|
|
2009-05-20 00:39:20 +00:00
|
|
|
void ManagedStaticBase::RegisterManagedStatic(void *(*Creator)(),
|
2006-09-28 00:31:55 +00:00
|
|
|
void (*Deleter)(void*)) const {
|
2014-04-17 20:30:35 +00:00
|
|
|
assert(Creator);
|
2009-06-16 17:33:51 +00:00
|
|
|
if (llvm_is_multithreaded()) {
|
2014-06-19 16:17:42 +00:00
|
|
|
std::lock_guard<std::recursive_mutex> Lock(GetManagedStaticMutex());
|
2009-05-20 00:39:20 +00:00
|
|
|
|
2014-04-09 04:20:00 +00:00
|
|
|
if (!Ptr) {
|
2014-04-17 20:30:35 +00:00
|
|
|
void* tmp = Creator();
|
2009-05-20 00:39:20 +00:00
|
|
|
|
2011-11-14 20:50:16 +00:00
|
|
|
TsanHappensBefore(this);
|
2014-03-03 18:02:34 +00:00
|
|
|
sys::MemoryFence();
|
2011-11-14 20:50:16 +00:00
|
|
|
|
|
|
|
// This write is racy against the first read in the ManagedStatic
|
|
|
|
// accessors. The race is benign because it does a second read after a
|
|
|
|
// memory fence, at which point it isn't possible to get a partial value.
|
|
|
|
TsanIgnoreWritesBegin();
|
2009-05-20 00:39:20 +00:00
|
|
|
Ptr = tmp;
|
2011-11-14 20:50:16 +00:00
|
|
|
TsanIgnoreWritesEnd();
|
2009-05-20 00:39:20 +00:00
|
|
|
DeleterFn = Deleter;
|
|
|
|
|
|
|
|
// Add to list of managed statics.
|
|
|
|
Next = StaticList;
|
|
|
|
StaticList = this;
|
|
|
|
}
|
|
|
|
} else {
|
2014-04-15 06:32:26 +00:00
|
|
|
assert(!Ptr && !DeleterFn && !Next &&
|
2009-05-30 01:09:53 +00:00
|
|
|
"Partially initialized ManagedStatic!?");
|
2014-04-17 20:30:35 +00:00
|
|
|
Ptr = Creator();
|
2009-05-20 00:39:20 +00:00
|
|
|
DeleterFn = Deleter;
|
2006-09-28 00:31:55 +00:00
|
|
|
|
2009-05-20 00:39:20 +00:00
|
|
|
// Add to list of managed statics.
|
|
|
|
Next = StaticList;
|
|
|
|
StaticList = this;
|
|
|
|
}
|
2006-09-28 00:31:55 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
void ManagedStaticBase::destroy() const {
|
2007-02-20 06:18:57 +00:00
|
|
|
assert(DeleterFn && "ManagedStatic not initialized correctly!");
|
2006-09-28 00:31:55 +00:00
|
|
|
assert(StaticList == this &&
|
|
|
|
"Not destroyed in reverse order of construction?");
|
|
|
|
// Unlink from list.
|
|
|
|
StaticList = Next;
|
2014-04-07 04:17:22 +00:00
|
|
|
Next = nullptr;
|
2006-09-28 00:31:55 +00:00
|
|
|
|
|
|
|
// Destroy memory.
|
|
|
|
DeleterFn(Ptr);
|
|
|
|
|
|
|
|
// Cleanup.
|
2014-04-07 04:17:22 +00:00
|
|
|
Ptr = nullptr;
|
|
|
|
DeleterFn = nullptr;
|
2006-09-28 00:31:55 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/// llvm_shutdown - Deallocate and destroy all ManagedStatic variables.
|
2006-09-29 18:43:14 +00:00
|
|
|
void llvm::llvm_shutdown() {
|
2014-06-19 16:17:42 +00:00
|
|
|
std::lock_guard<std::recursive_mutex> Lock(GetManagedStaticMutex());
|
|
|
|
|
2006-09-28 00:31:55 +00:00
|
|
|
while (StaticList)
|
|
|
|
StaticList->destroy();
|
|
|
|
}
|