llvm-6502/include/llvm/Support/ThreadLocal.h
2013-01-10 00:45:19 +00:00

64 lines
2.1 KiB
C++

//===- llvm/Support/ThreadLocal.h - Thread Local Data ------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares the llvm::sys::ThreadLocal class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_SUPPORT_THREADLOCAL_H
#define LLVM_SUPPORT_THREADLOCAL_H
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/Threading.h"
#include <cassert>
namespace llvm {
namespace sys {
// ThreadLocalImpl - Common base class of all ThreadLocal instantiations.
// YOU SHOULD NEVER USE THIS DIRECTLY.
class ThreadLocalImpl {
typedef uint64_t ThreadLocalDataTy;
/// \brief Platform-specific thread local data.
///
/// This is embedded in the class and we avoid malloc'ing/free'ing it,
/// to make this class more safe for use along with CrashRecoveryContext.
union {
char data[sizeof(ThreadLocalDataTy)];
ThreadLocalDataTy align_data;
};
public:
ThreadLocalImpl();
virtual ~ThreadLocalImpl();
void setInstance(const void* d);
const void* getInstance();
void removeInstance();
};
/// ThreadLocal - A class used to abstract thread-local storage. It holds,
/// for each thread, a pointer a single object of type T.
template<class T>
class ThreadLocal : public ThreadLocalImpl {
public:
ThreadLocal() : ThreadLocalImpl() { }
/// get - Fetches a pointer to the object associated with the current
/// thread. If no object has yet been associated, it returns NULL;
T* get() { return static_cast<T*>(getInstance()); }
// set - Associates a pointer to an object with the current thread.
void set(T* d) { setInstance(d); }
// erase - Removes the pointer associated with the current thread.
void erase() { removeInstance(); }
};
}
}
#endif