Line data    Source code

       1             : //===- llvm/Support/ThreadLocal.h - Thread Local Data ------------*- C++ -*-===//
       2             : //
       3             : //                     The LLVM Compiler Infrastructure
       4             : //
       5             : // This file is distributed under the University of Illinois Open Source
       6             : // License. See LICENSE.TXT for details.
       7             : //
       8             : //===----------------------------------------------------------------------===//
       9             : //
      10             : // This file declares the llvm::sys::ThreadLocal class.
      11             : //
      12             : //===----------------------------------------------------------------------===//
      13             : 
      14             : #ifndef LLVM_SUPPORT_THREADLOCAL_H
      15             : #define LLVM_SUPPORT_THREADLOCAL_H
      16             : 
      17             : #include "llvm/Support/DataTypes.h"
      18             : #include "llvm/Support/Threading.h"
      19             : #include <cassert>
      20             : 
      21             : namespace llvm {
      22             :   namespace sys {
      23             :     // ThreadLocalImpl - Common base class of all ThreadLocal instantiations.
      24             :     // YOU SHOULD NEVER USE THIS DIRECTLY.
      25             :     class ThreadLocalImpl {
      26             :       typedef uint64_t ThreadLocalDataTy;
      27             :       /// Platform-specific thread local data.
      28             :       ///
      29             :       /// This is embedded in the class and we avoid malloc'ing/free'ing it,
      30             :       /// to make this class more safe for use along with CrashRecoveryContext.
      31             :       union {
      32             :         char data[sizeof(ThreadLocalDataTy)];
      33             :         ThreadLocalDataTy align_data;
      34             :       };
      35             :     public:
      36             :       ThreadLocalImpl();
      37             :       virtual ~ThreadLocalImpl();
      38             :       void setInstance(const void* d);
      39             :       void *getInstance();
      40             :       void removeInstance();
      41             :     };
      42             : 
      43             :     /// ThreadLocal - A class used to abstract thread-local storage.  It holds,
      44             :     /// for each thread, a pointer a single object of type T.
      45             :     template<class T>
      46           1 :     class ThreadLocal : public ThreadLocalImpl {
      47             :     public:
      48        2608 :       ThreadLocal() : ThreadLocalImpl() { }
      49             : 
      50             :       /// get - Fetches a pointer to the object associated with the current
      51             :       /// thread.  If no object has yet been associated, it returns NULL;
      52       18159 :       T* get() { return static_cast<T*>(getInstance()); }
      53             : 
      54             :       // set - Associates a pointer to an object with the current thread.
      55       10201 :       void set(T* d) { setInstance(d); }
      56             : 
      57             :       // erase - Removes the pointer associated with the current thread.
      58           2 :       void erase() { removeInstance(); }
      59             :     };
      60             :   }
      61             : }
      62             : 
      63             : #endif