X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FSupport%2FMutex.cpp;h=c8d3844d0c9618a19133836c06aabac831f42e35;hb=9c23685dd25370a9a255052e44fa609b8ce455c0;hp=6a873cb0004244acc5dd0f54767cd64839b446cf;hpb=08b73a30bbb6407c7b48a734a29f65f4c8ddd782;p=oota-llvm.git diff --git a/lib/Support/Mutex.cpp b/lib/Support/Mutex.cpp index 6a873cb0004..c8d3844d0c9 100644 --- a/lib/Support/Mutex.cpp +++ b/lib/Support/Mutex.cpp @@ -40,109 +40,74 @@ bool MutexImpl::tryacquire() { return true; } namespace llvm { using namespace sys; - -// This variable is useful for situations where the pthread library has been -// compiled with weak linkage for its interface symbols. This allows the -// threading support to be turned off by simply not linking against -lpthread. -// In that situation, the value of pthread_mutex_init will be 0 and -// consequently pthread_enabled will be false. In such situations, all the -// pthread operations become no-ops and the functions all return false. If -// pthread_mutex_init does have an address, then mutex support is enabled. -// Note: all LLVM tools will link against -lpthread if its available since it -// is configured into the LIBS variable. -// Note: this line of code generates a warning if pthread_mutex_init is not -// declared with weak linkage. It's safe to ignore the warning. -static const bool pthread_enabled = true; - // Construct a Mutex using pthread calls MutexImpl::MutexImpl( bool recursive) - : data_(0) + : data_(nullptr) { - if (pthread_enabled) - { - // Declare the pthread_mutex data structures - pthread_mutex_t* mutex = - static_cast(malloc(sizeof(pthread_mutex_t))); - pthread_mutexattr_t attr; - - // Initialize the mutex attributes - int errorcode = pthread_mutexattr_init(&attr); - assert(errorcode == 0); - - // Initialize the mutex as a recursive mutex, if requested, or normal - // otherwise. - int kind = ( recursive ? PTHREAD_MUTEX_RECURSIVE : PTHREAD_MUTEX_NORMAL ); - errorcode = pthread_mutexattr_settype(&attr, kind); - assert(errorcode == 0); - -#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__) && !defined(__DragonFly__) - // Make it a process local mutex - errorcode = pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_PRIVATE); - assert(errorcode == 0); -#endif - - // Initialize the mutex - errorcode = pthread_mutex_init(mutex, &attr); - assert(errorcode == 0); - - // Destroy the attributes - errorcode = pthread_mutexattr_destroy(&attr); - assert(errorcode == 0); - - // Assign the data member - data_ = mutex; - } + // Declare the pthread_mutex data structures + pthread_mutex_t* mutex = + static_cast(malloc(sizeof(pthread_mutex_t))); + pthread_mutexattr_t attr; + + // Initialize the mutex attributes + int errorcode = pthread_mutexattr_init(&attr); + assert(errorcode == 0); (void)errorcode; + + // Initialize the mutex as a recursive mutex, if requested, or normal + // otherwise. + int kind = ( recursive ? PTHREAD_MUTEX_RECURSIVE : PTHREAD_MUTEX_NORMAL ); + errorcode = pthread_mutexattr_settype(&attr, kind); + assert(errorcode == 0); + + // Initialize the mutex + errorcode = pthread_mutex_init(mutex, &attr); + assert(errorcode == 0); + + // Destroy the attributes + errorcode = pthread_mutexattr_destroy(&attr); + assert(errorcode == 0); + + // Assign the data member + data_ = mutex; } // Destruct a Mutex MutexImpl::~MutexImpl() { - if (pthread_enabled) - { - pthread_mutex_t* mutex = static_cast(data_); - assert(mutex != 0); - pthread_mutex_destroy(mutex); - free(mutex); - } + pthread_mutex_t* mutex = static_cast(data_); + assert(mutex != nullptr); + pthread_mutex_destroy(mutex); + free(mutex); } bool MutexImpl::acquire() { - if (pthread_enabled) - { - pthread_mutex_t* mutex = static_cast(data_); - assert(mutex != 0); - - int errorcode = pthread_mutex_lock(mutex); - return errorcode == 0; - } else return false; + pthread_mutex_t* mutex = static_cast(data_); + assert(mutex != nullptr); + + int errorcode = pthread_mutex_lock(mutex); + return errorcode == 0; } bool MutexImpl::release() { - if (pthread_enabled) - { - pthread_mutex_t* mutex = static_cast(data_); - assert(mutex != 0); - - int errorcode = pthread_mutex_unlock(mutex); - return errorcode == 0; - } else return false; + pthread_mutex_t* mutex = static_cast(data_); + assert(mutex != nullptr); + + int errorcode = pthread_mutex_unlock(mutex); + return errorcode == 0; } bool MutexImpl::tryacquire() { - if (pthread_enabled) - { - pthread_mutex_t* mutex = static_cast(data_); - assert(mutex != 0); - - int errorcode = pthread_mutex_trylock(mutex); - return errorcode == 0; - } else return false; + pthread_mutex_t* mutex = static_cast(data_); + assert(mutex != nullptr); + + int errorcode = pthread_mutex_trylock(mutex); + return errorcode == 0; } }