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Diffstat (limited to 'contrib/llvm/lib/Support/RWMutex.cpp')
-rw-r--r-- | contrib/llvm/lib/Support/RWMutex.cpp | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Support/RWMutex.cpp b/contrib/llvm/lib/Support/RWMutex.cpp new file mode 100644 index 0000000..6a34f2d --- /dev/null +++ b/contrib/llvm/lib/Support/RWMutex.cpp @@ -0,0 +1,125 @@ +//===- RWMutex.cpp - 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 implements the llvm::sys::RWMutex class. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Config/config.h" +#include "llvm/Support/RWMutex.h" +#include <cstring> + +//===----------------------------------------------------------------------===// +//=== WARNING: Implementation here must contain only TRULY operating system +//=== independent code. +//===----------------------------------------------------------------------===// + +#if !defined(LLVM_ENABLE_THREADS) || LLVM_ENABLE_THREADS == 0 +// Define all methods as no-ops if threading is explicitly disabled +namespace llvm { +using namespace sys; +RWMutexImpl::RWMutexImpl() { } +RWMutexImpl::~RWMutexImpl() { } +bool RWMutexImpl::reader_acquire() { return true; } +bool RWMutexImpl::reader_release() { return true; } +bool RWMutexImpl::writer_acquire() { return true; } +bool RWMutexImpl::writer_release() { return true; } +} +#else + +#if defined(HAVE_PTHREAD_H) && defined(HAVE_PTHREAD_RWLOCK_INIT) + +#include <cassert> +#include <pthread.h> +#include <stdlib.h> + +namespace llvm { +using namespace sys; + +// Construct a RWMutex using pthread calls +RWMutexImpl::RWMutexImpl() + : data_(0) +{ + // Declare the pthread_rwlock data structures + pthread_rwlock_t* rwlock = + static_cast<pthread_rwlock_t*>(malloc(sizeof(pthread_rwlock_t))); + +#ifdef __APPLE__ + // Workaround a bug/mis-feature in Darwin's pthread_rwlock_init. + bzero(rwlock, sizeof(pthread_rwlock_t)); +#endif + + // Initialize the rwlock + int errorcode = pthread_rwlock_init(rwlock, NULL); + (void)errorcode; + assert(errorcode == 0); + + // Assign the data member + data_ = rwlock; +} + +// Destruct a RWMutex +RWMutexImpl::~RWMutexImpl() +{ + pthread_rwlock_t* rwlock = static_cast<pthread_rwlock_t*>(data_); + assert(rwlock != 0); + pthread_rwlock_destroy(rwlock); + free(rwlock); +} + +bool +RWMutexImpl::reader_acquire() +{ + pthread_rwlock_t* rwlock = static_cast<pthread_rwlock_t*>(data_); + assert(rwlock != 0); + + int errorcode = pthread_rwlock_rdlock(rwlock); + return errorcode == 0; +} + +bool +RWMutexImpl::reader_release() +{ + pthread_rwlock_t* rwlock = static_cast<pthread_rwlock_t*>(data_); + assert(rwlock != 0); + + int errorcode = pthread_rwlock_unlock(rwlock); + return errorcode == 0; +} + +bool +RWMutexImpl::writer_acquire() +{ + pthread_rwlock_t* rwlock = static_cast<pthread_rwlock_t*>(data_); + assert(rwlock != 0); + + int errorcode = pthread_rwlock_wrlock(rwlock); + return errorcode == 0; +} + +bool +RWMutexImpl::writer_release() +{ + pthread_rwlock_t* rwlock = static_cast<pthread_rwlock_t*>(data_); + assert(rwlock != 0); + + int errorcode = pthread_rwlock_unlock(rwlock); + return errorcode == 0; +} + +} + +#elif defined(LLVM_ON_UNIX) +#include "Unix/RWMutex.inc" +#elif defined( LLVM_ON_WIN32) +#include "Windows/RWMutex.inc" +#else +#warning Neither LLVM_ON_UNIX nor LLVM_ON_WIN32 was set in Support/Mutex.cpp +#endif +#endif |