vendor/llvm/llvm-r73879

5 files changed, 300 insertions, 7 deletions

diff --git a/include/llvm/System/Atomic.h b/include/llvm/System/Atomic.h
index cb9277cc35ec8..adbb975298e81 100644
--- a/include/llvm/System/Atomic.h
+++ b/include/llvm/System/Atomic.h
@@ -24,6 +24,8 @@ namespace llvm {
     cas_flag CompareAndSwap(volatile cas_flag* ptr,
                             cas_flag new_value,
                             cas_flag old_value);
+    cas_flag AtomicIncrement(volatile cas_flag* ptr);
+    cas_flag AtomicDecrement(volatile cas_flag* ptr);
   }
 }
 
diff --git a/include/llvm/System/Mutex.h b/include/llvm/System/Mutex.h
index 4f3849341aa1f..d2c457dbc91c6 100644
--- a/include/llvm/System/Mutex.h
+++ b/include/llvm/System/Mutex.h
@@ -14,12 +14,15 @@
 #ifndef LLVM_SYSTEM_MUTEX_H
 #define LLVM_SYSTEM_MUTEX_H
 
+#include "llvm/System/Threading.h"
+#include <cassert>
+
 namespace llvm
 {
   namespace sys
   {
     /// @brief Platform agnostic Mutex class.
-    class Mutex
+    class MutexImpl
     {
     /// @name Constructors
     /// @{
@@ -30,11 +33,11 @@ namespace llvm
       /// also more likely to deadlock (same thread can't acquire more than
       /// once).
       /// @brief Default Constructor.
-      explicit Mutex(bool recursive = true);
+      explicit MutexImpl(bool recursive = true);
 
       /// Releases and removes the lock
       /// @brief Destructor
-      ~Mutex();
+      ~MutexImpl();
 
     /// @}
     /// @name Methods
@@ -66,18 +69,81 @@ namespace llvm
     /// @name Platform Dependent Data
     /// @{
     private:
-#ifdef ENABLE_THREADS
       void* data_; ///< We don't know what the data will be
-#endif
 
     /// @}
     /// @name Do Not Implement
     /// @{
     private:
-      Mutex(const Mutex & original);
-      void operator=(const Mutex &);
+      MutexImpl(const MutexImpl & original);
+      void operator=(const MutexImpl &);
     /// @}
     };
+    
+    
+    /// SmartMutex - A mutex with a compile time constant parameter that 
+    /// indicates whether this mutex should become a no-op when we're not
+    /// running in multithreaded mode.
+    template<bool mt_only>
+    class SmartMutex : public MutexImpl {
+      unsigned acquired;
+      bool recursive;
+    public:
+      explicit SmartMutex(bool rec = true) :
+        MutexImpl(rec), acquired(0), recursive(rec) { }
+      
+      bool acquire() {
+        if (!mt_only || llvm_is_multithreaded())
+          return MutexImpl::acquire();
+        
+        // Single-threaded debugging code.  This would be racy in multithreaded
+        // mode, but provides not sanity checks in single threaded mode.
+        assert((recursive || acquired == 0) && "Lock already acquired!!");
+        ++acquired;
+        return true;
+      }
+
+      bool release() {
+        if (!mt_only || llvm_is_multithreaded())
+          return MutexImpl::release();
+        
+        // Single-threaded debugging code.  This would be racy in multithreaded
+        // mode, but provides not sanity checks in single threaded mode.
+        assert(((recursive && acquired) || (acquired == 1)) &&
+               "Lock not acquired before release!");
+        --acquired;
+        return true;
+      }
+
+      bool tryacquire() {
+        if (!mt_only || llvm_is_multithreaded())
+          return MutexImpl::tryacquire();
+        return true;
+      }
+      
+      private:
+        SmartMutex(const SmartMutex<mt_only> & original);
+        void operator=(const SmartMutex<mt_only> &);
+    };
+    
+    /// Mutex - A standard, always enforced mutex.
+    typedef SmartMutex<false> Mutex;
+    
+    template<bool mt_only>
+    class SmartScopedLock  {
+      SmartMutex<mt_only>* mtx;
+      
+    public:
+      SmartScopedLock(SmartMutex<mt_only>* m) : mtx(m) {
+        mtx->acquire();
+      }
+      
+      ~SmartScopedLock() {
+        mtx->release();
+      }
+    };
+    
+    typedef SmartScopedLock<false> ScopedLock;
   }
 }
 
diff --git a/include/llvm/System/Path.h b/include/llvm/System/Path.h
index de2f173ae4175..05be2212758b4 100644
--- a/include/llvm/System/Path.h
+++ b/include/llvm/System/Path.h
@@ -309,6 +309,11 @@ namespace sys {
       /// @brief Determine if the path is absolute.
       bool isAbsolute() const;
 
+      /// This function determines if the path name is absolute, as opposed to
+      /// relative.
+      /// @brief Determine if the path is absolute.
+      static bool isAbsolute(const char *NameStart, unsigned NameLen);
+
       /// This function opens the file associated with the path name provided by
       /// the Path object and reads its magic number. If the magic number at the
       /// start of the file matches \p magic, true is returned. In all other
diff --git a/include/llvm/System/RWMutex.h b/include/llvm/System/RWMutex.h
new file mode 100644
index 0000000000000..e577d457afb51
--- /dev/null
+++ b/include/llvm/System/RWMutex.h
@@ -0,0 +1,175 @@
+//===- RWMutex.h - Reader/Writer Mutual Exclusion Lock ----------*- 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::RWMutex class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SYSTEM_RWMUTEX_H
+#define LLVM_SYSTEM_RWMUTEX_H
+
+#include "llvm/System/Threading.h"
+#include <cassert>
+
+namespace llvm
+{
+  namespace sys
+  {
+    /// @brief Platform agnostic RWMutex class.
+    class RWMutexImpl
+    {
+    /// @name Constructors
+    /// @{
+    public:
+
+      /// Initializes the lock but doesn't acquire it.
+      /// @brief Default Constructor.
+      explicit RWMutexImpl();
+
+      /// Releases and removes the lock
+      /// @brief Destructor
+      ~RWMutexImpl();
+
+    /// @}
+    /// @name Methods
+    /// @{
+    public:
+
+      /// Attempts to unconditionally acquire the lock in reader mode. If the
+      /// lock is held by a writer, this method will wait until it can acquire
+      /// the lock. 
+      /// @returns false if any kind of error occurs, true otherwise.
+      /// @brief Unconditionally acquire the lock in reader mode.
+      bool reader_acquire();
+
+      /// Attempts to release the lock in reader mode.
+      /// @returns false if any kind of error occurs, true otherwise.
+      /// @brief Unconditionally release the lock in reader mode.
+      bool reader_release();
+
+      /// Attempts to unconditionally acquire the lock in reader mode. If the
+      /// lock is held by any readers, this method will wait until it can
+      /// acquire the lock. 
+      /// @returns false if any kind of error occurs, true otherwise.
+      /// @brief Unconditionally acquire the lock in writer mode.
+      bool writer_acquire();
+
+      /// Attempts to release the lock in writer mode.
+      /// @returns false if any kind of error occurs, true otherwise.
+      /// @brief Unconditionally release the lock in write mode.
+      bool writer_release();
+
+    //@}
+    /// @name Platform Dependent Data
+    /// @{
+    private:
+      void* data_; ///< We don't know what the data will be
+
+    /// @}
+    /// @name Do Not Implement
+    /// @{
+    private:
+      RWMutexImpl(const RWMutexImpl & original);
+      void operator=(const RWMutexImpl &);
+    /// @}
+    };
+    
+    /// SmartMutex - An R/W mutex with a compile time constant parameter that 
+    /// indicates whether this mutex should become a no-op when we're not
+    /// running in multithreaded mode.
+    template<bool mt_only>
+    class SmartRWMutex : public RWMutexImpl {
+      unsigned readers, writers;
+    public:
+      explicit SmartRWMutex() : RWMutexImpl(), readers(0), writers(0) { }
+      
+      bool reader_acquire() {
+        if (!mt_only || llvm_is_multithreaded())
+          return RWMutexImpl::reader_acquire();
+        
+        // Single-threaded debugging code.  This would be racy in multithreaded
+        // mode, but provides not sanity checks in single threaded mode.
+        ++readers;
+        return true;
+      }
+      
+      bool reader_release() {
+        if (!mt_only || llvm_is_multithreaded())
+          return RWMutexImpl::reader_release();
+        
+        // Single-threaded debugging code.  This would be racy in multithreaded
+        // mode, but provides not sanity checks in single threaded mode.
+        assert(readers > 0 && "Reader lock not acquired before release!");
+        --readers;
+        return true;
+      }
+      
+      bool writer_acquire() {
+        if (!mt_only || llvm_is_multithreaded())
+          return RWMutexImpl::writer_acquire();
+        
+        // Single-threaded debugging code.  This would be racy in multithreaded
+        // mode, but provides not sanity checks in single threaded mode.
+        assert(writers == 0 && "Writer lock already acquired!");
+        ++writers;
+        return true;
+      }
+      
+      bool writer_release() {
+        if (!mt_only || llvm_is_multithreaded())
+          return RWMutexImpl::writer_release();
+        
+        // Single-threaded debugging code.  This would be racy in multithreaded
+        // mode, but provides not sanity checks in single threaded mode.
+        assert(writers == 1 && "Writer lock not acquired before release!");
+        --writers;
+        return true;
+      }
+      
+    private:
+      SmartRWMutex(const SmartRWMutex<mt_only> & original);
+      void operator=(const SmartRWMutex<mt_only> &);
+    };
+    typedef SmartRWMutex<false> RWMutex;
+    
+    /// ScopedReader - RAII acquisition of a reader lock
+    template<bool mt_only>
+    struct SmartScopedReader {
+      SmartRWMutex<mt_only>* mutex;
+      
+      explicit SmartScopedReader(SmartRWMutex<mt_only>* m) {
+        mutex = m;
+        mutex->reader_acquire();
+      }
+      
+      ~SmartScopedReader() {
+        mutex->reader_release();
+      }
+    };
+    typedef SmartScopedReader<false> ScopedReader;
+    
+    /// ScopedWriter - RAII acquisition of a writer lock
+    template<bool mt_only>
+    struct SmartScopedWriter {
+      SmartRWMutex<mt_only>* mutex;
+      
+      explicit SmartScopedWriter(SmartRWMutex<mt_only>* m) {
+        mutex = m;
+        mutex->writer_acquire();
+      }
+      
+      ~SmartScopedWriter() {
+        mutex->writer_release();
+      }
+    };
+    typedef SmartScopedWriter<false> ScopedWriter;
+  }
+}
+
+#endif
diff --git a/include/llvm/System/Threading.h b/include/llvm/System/Threading.h
new file mode 100644
index 0000000000000..42d2f89bcb825
--- /dev/null
+++ b/include/llvm/System/Threading.h
@@ -0,0 +1,45 @@
+//===-- llvm/System/Threading.h - Control multithreading mode --*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// TThis file defines llvm_start_multithreaded() and friends.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SYSTEM_THREADING_H
+#define LLVM_SYSTEM_THREADING_H
+
+namespace llvm {
+  /// llvm_start_multithreaded - Allocate and initialize structures needed to
+  /// make LLVM safe for multithreading.  The return value indicates whether
+  /// multithreaded initialization succeeded.  LLVM will still be operational
+  /// on "failed" return, and will still be safe for hosting threading 
+  /// applications in the JIT, but will not be safe for concurrent calls to the
+  /// LLVM APIs.
+  /// THIS MUST EXECUTE IN ISOLATION FROM ALL OTHER LLVM API CALLS.
+  bool llvm_start_multithreaded();
+  
+  /// llvm_stop_multithreaded - Deallocate structures necessary to make LLVM
+  /// safe for multithreading.
+  /// THIS MUST EXECUTE IN ISOLATION FROM ALL OTHER LLVM API CALLS.
+  void llvm_stop_multithreaded();
+  
+  /// llvm_is_multithreaded - Check whether LLVM is executing in thread-safe
+  /// mode or not.
+  bool llvm_is_multithreaded();
+  
+  /// acquire_global_lock - Acquire the global lock.  This is a no-op if called
+  /// before llvm_start_multithreaded().
+  void llvm_acquire_global_lock();
+  
+  /// release_global_lock - Release the global lock.  This is a no-op if called
+  /// before llvm_start_multithreaded().
+  void llvm_release_global_lock();
+}
+
+#endif