92 lines
2.6 KiB
C++
92 lines
2.6 KiB
C++
//===-- ManagedStatic.cpp - Static Global wrapper -------------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file implements the ManagedStatic class and llvm_shutdown().
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Support/ManagedStatic.h"
|
|
#include "llvm/Support/Threading.h"
|
|
#include <cassert>
|
|
#include <mutex>
|
|
using namespace llvm;
|
|
|
|
static const ManagedStaticBase *StaticList = nullptr;
|
|
static std::recursive_mutex *ManagedStaticMutex = nullptr;
|
|
LLVM_DEFINE_ONCE_FLAG(mutex_init_flag);
|
|
|
|
#if 0
|
|
|
|
static void initializeMutex() {
|
|
ManagedStaticMutex = new std::recursive_mutex();
|
|
}
|
|
|
|
static std::recursive_mutex* getManagedStaticMutex() {
|
|
// We need to use a function local static here, since this can get called
|
|
// during a static constructor and we need to guarantee that it's initialized
|
|
// correctly.
|
|
llvm::call_once(mutex_init_flag, initializeMutex);
|
|
return ManagedStaticMutex;
|
|
}
|
|
|
|
#else
|
|
|
|
// SwiftShader: from https://reviews.llvm.org/D83372
|
|
static std::recursive_mutex *getManagedStaticMutex() {
|
|
static std::recursive_mutex m;
|
|
return &m;
|
|
}
|
|
|
|
#endif
|
|
|
|
void ManagedStaticBase::RegisterManagedStatic(void *(*Creator)(),
|
|
void (*Deleter)(void*)) const {
|
|
assert(Creator);
|
|
std::lock_guard<std::recursive_mutex> Lock(*getManagedStaticMutex());
|
|
|
|
if (!Ptr.load(std::memory_order_relaxed)) {
|
|
void *Tmp = Creator();
|
|
|
|
Ptr.store(Tmp, std::memory_order_release);
|
|
DeleterFn = Deleter;
|
|
|
|
// Add to list of managed statics.
|
|
Next = StaticList;
|
|
StaticList = this;
|
|
}
|
|
}
|
|
|
|
void ManagedStaticBase::destroy() const {
|
|
assert(DeleterFn && "ManagedStatic not initialized correctly!");
|
|
assert(StaticList == this &&
|
|
"Not destroyed in reverse order of construction?");
|
|
// Unlink from list.
|
|
StaticList = Next;
|
|
Next = nullptr;
|
|
|
|
// Destroy memory.
|
|
DeleterFn(Ptr);
|
|
|
|
// Cleanup.
|
|
Ptr = nullptr;
|
|
DeleterFn = nullptr;
|
|
}
|
|
|
|
/// llvm_shutdown - Deallocate and destroy all ManagedStatic variables.
|
|
void llvm::llvm_shutdown() {
|
|
// SwiftShader: from https://reviews.llvm.org/D83372
|
|
// This may be called after the mutex is destroyed. Instead of fixing this,
|
|
// don't bother locking the mutex, and require llvm_shutdown to be called from
|
|
// exactly one thread.
|
|
// std::lock_guard<std::recursive_mutex> Lock(*getManagedStaticMutex());
|
|
|
|
while (StaticList)
|
|
StaticList->destroy();
|
|
}
|