From ee448630bdf7eb6037fe2c50518d32010c433ca3 Mon Sep 17 00:00:00 2001 From: Reid Spencer Date: Tue, 12 Jul 2005 15:51:55 +0000 Subject: For PR540: This patch completes the changes for making lli thread-safe. Here's the list of changes: * The Support/ThreadSupport* files were removed and replaced with the MutexGuard.h file since all ThreadSupport* declared was a Mutex Guard. The implementation of MutexGuard.h is now based on sys::Mutex which hides its implementation and makes it unnecessary to have the -NoSupport.h and -PThreads.h versions of ThreadSupport. * All places in ExecutionEngine that previously referred to "Mutex" now refer to sys::Mutex * All places in ExecutionEngine that previously referred to "MutexLocker" now refer to MutexGuard (this is frivolous but I believe the technically correct name for such a class is "Guard" not a "Locker"). These changes passed all of llvm-test. All we need now are some test cases that actually use multiple threads. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22404 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/Support/MutexGuard.h | 47 +++++++++---------- include/llvm/Support/ThreadSupport-NoSupport.h | 34 -------------- include/llvm/Support/ThreadSupport-PThreads.h | 65 -------------------------- include/llvm/Support/ThreadSupport.h.in | 42 ----------------- 4 files changed, 23 insertions(+), 165 deletions(-) delete mode 100644 include/llvm/Support/ThreadSupport-NoSupport.h delete mode 100644 include/llvm/Support/ThreadSupport-PThreads.h delete mode 100644 include/llvm/Support/ThreadSupport.h.in (limited to 'include/llvm/Support') diff --git a/include/llvm/Support/MutexGuard.h b/include/llvm/Support/MutexGuard.h index bed1a9cec7..24bbbe1bb3 100644 --- a/include/llvm/Support/MutexGuard.h +++ b/include/llvm/Support/MutexGuard.h @@ -1,4 +1,4 @@ -//===-- Support/ThreadSupport.h - Generic threading support -----*- C++ -*-===// +//===-- Support/MutexGuard.h - Acquire/Release Mutex In Scope ---*- C++ -*-===// // // The LLVM Compiler Infrastructure // @@ -7,36 +7,35 @@ // //===----------------------------------------------------------------------===// // -// This file defines platform-agnostic interfaces that can be used to write -// multi-threaded programs. Autoconf is used to chose the correct -// implementation of these interfaces, or default to a non-thread-capable system -// if no matching system support is available. +// This file defines a guard for a block of code that ensures a Mutex is locked +// upon construction and released upon destruction. // //===----------------------------------------------------------------------===// -#ifndef LLVM_SUPPORT_THREADSUPPORT_H -#define LLVM_SUPPORT_THREADSUPPORT_H +#ifndef LLVM_SUPPORT_MUTEXGUARD_H +#define LLVM_SUPPORT_MUTEXGUARD_H -#undef HAVE_PTHREAD_MUTEX_LOCK - -#ifdef HAVE_PTHREAD_MUTEX_LOCK -#include "llvm/Support/ThreadSupport-PThreads.h" -#else -#include "llvm/Support/ThreadSupport-NoSupport.h" -#endif // If no system support is available +#include namespace llvm { - /// MutexLocker - Instances of this class acquire a given Lock when - /// constructed and hold that lock until destruction. - /// - class MutexLocker { - Mutex &M; - MutexLocker(const MutexLocker &); // DO NOT IMPLEMENT - void operator=(const MutexLocker &); // DO NOT IMPLEMENT + /// Instances of this class acquire a given Mutex Lock when constructed and + /// hold that lock until destruction. The intention is to instantiate one of + /// these on the stack at the top of some scope to be assured that C++ + /// destruction of the object will always release the Mutex and thus avoid + /// a host of nasty multi-threading problems in the face of exceptions, etc. + /// @brief Guard a section of code with a Mutex. + class MutexGuard { + sys::Mutex &M; + MutexGuard(const MutexGuard &); // DO NOT IMPLEMENT + void operator=(const MutexGuard &); // DO NOT IMPLEMENT public: - MutexLocker(Mutex &m) : M(m) { M.acquire(); } - ~MutexLocker() { M.release(); } + MutexGuard(sys::Mutex &m) : M(m) { M.acquire(); } + ~MutexGuard() { M.release(); } + /// holds - Returns true if this locker instance holds the specified lock. + /// This is mostly used in assertions to validate that the correct mutex + /// is held. + bool holds(const sys::Mutex& lock) const { return &M == &lock; } }; } -#endif // SUPPORT_THREADSUPPORT_H +#endif // LLVM_SUPPORT_MUTEXGUARD_H diff --git a/include/llvm/Support/ThreadSupport-NoSupport.h b/include/llvm/Support/ThreadSupport-NoSupport.h deleted file mode 100644 index 058f82b41f..0000000000 --- a/include/llvm/Support/ThreadSupport-NoSupport.h +++ /dev/null @@ -1,34 +0,0 @@ -//===-- llvm/Support/ThreadSupport-NoSupport.h - Generic Impl ---*- C++ -*-===// -// -// The LLVM Compiler Infrastructure -// -// This file was developed by the LLVM research group and is distributed under -// the University of Illinois Open Source License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file defines a generic ThreadSupport implementation used when there is -// no supported threading mechanism on the current system. Users should never -// #include this file directly! -// -//===----------------------------------------------------------------------===// - -// Users should never #include this file directly! As such, no include guards -// are needed. - -#ifndef LLVM_SUPPORT_THREADSUPPORT_H -#error "Code should not #include Support/ThreadSupport-NoSupport.h directly!" -#endif - -namespace llvm { - /// Mutex - This class allows user code to protect variables shared between - /// threads. It implements a "recursive" mutex, to simplify user code. - /// - /// Since there is no platform support for _creating threads_, the non-thread - /// implementation of this class is a noop. - /// - struct Mutex { - void acquire () {} - void release () {} - }; -} diff --git a/include/llvm/Support/ThreadSupport-PThreads.h b/include/llvm/Support/ThreadSupport-PThreads.h deleted file mode 100644 index 84c6fac588..0000000000 --- a/include/llvm/Support/ThreadSupport-PThreads.h +++ /dev/null @@ -1,65 +0,0 @@ -//===-- llvm/Support/ThreadSupport-PThreads.h - PThreads support *- C++ -*-===// -// -// The LLVM Compiler Infrastructure -// -// This file was developed by the LLVM research group and is distributed under -// the University of Illinois Open Source License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file defines pthreads implementations of the generic threading -// mechanisms. Users should never #include this file directly! -// -//===----------------------------------------------------------------------===// - -// Users should never #include this file directly! As such, no include guards -// are needed. - -#ifndef LLVM_SUPPORT_THREADSUPPORT_H -#error "Code should not #include Support/ThreadSupport/PThreads.h directly!" -#endif - -#include - -namespace llvm { - - /// Mutex - This class allows user code to protect variables shared between - /// threads. It implements a "recursive" mutex, to simplify user code. - /// - class Mutex { - pthread_mutex_t mutex; - Mutex(const Mutex &); // DO NOT IMPLEMENT - void operator=(const Mutex &); // DO NOT IMPLEMENT - public: - Mutex() { - // Initialize the mutex as a recursive mutex - pthread_mutexattr_t Attr; - int errorcode = pthread_mutexattr_init(&Attr); - assert(errorcode == 0); - - errorcode = pthread_mutexattr_settype(&Attr, PTHREAD_MUTEX_RECURSIVE); - assert(errorcode == 0); - - errorcode = pthread_mutex_init(&mutex, &Attr); - assert(errorcode == 0); - - errorcode = pthread_mutexattr_destroy(&Attr); - assert(errorcode == 0); - } - - ~Mutex() { - int errorcode = pthread_mutex_destroy(&mutex); - assert(errorcode == 0); - } - - void acquire () { - int errorcode = pthread_mutex_lock(&mutex); - assert(errorcode == 0); - } - - void release () { - int errorcode = pthread_mutex_unlock(&mutex); - assert(errorcode == 0); - } - }; -} // end namespace llvm diff --git a/include/llvm/Support/ThreadSupport.h.in b/include/llvm/Support/ThreadSupport.h.in deleted file mode 100644 index bed1a9cec7..0000000000 --- a/include/llvm/Support/ThreadSupport.h.in +++ /dev/null @@ -1,42 +0,0 @@ -//===-- Support/ThreadSupport.h - Generic threading support -----*- C++ -*-===// -// -// The LLVM Compiler Infrastructure -// -// This file was developed by the LLVM research group and is distributed under -// the University of Illinois Open Source License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file defines platform-agnostic interfaces that can be used to write -// multi-threaded programs. Autoconf is used to chose the correct -// implementation of these interfaces, or default to a non-thread-capable system -// if no matching system support is available. -// -//===----------------------------------------------------------------------===// - -#ifndef LLVM_SUPPORT_THREADSUPPORT_H -#define LLVM_SUPPORT_THREADSUPPORT_H - -#undef HAVE_PTHREAD_MUTEX_LOCK - -#ifdef HAVE_PTHREAD_MUTEX_LOCK -#include "llvm/Support/ThreadSupport-PThreads.h" -#else -#include "llvm/Support/ThreadSupport-NoSupport.h" -#endif // If no system support is available - -namespace llvm { - /// MutexLocker - Instances of this class acquire a given Lock when - /// constructed and hold that lock until destruction. - /// - class MutexLocker { - Mutex &M; - MutexLocker(const MutexLocker &); // DO NOT IMPLEMENT - void operator=(const MutexLocker &); // DO NOT IMPLEMENT - public: - MutexLocker(Mutex &m) : M(m) { M.acquire(); } - ~MutexLocker() { M.release(); } - }; -} - -#endif // SUPPORT_THREADSUPPORT_H -- cgit v1.2.3