2010-08-12 Kostya Serebryany <kcc@google.com>
Paolo Carlini <paolo.carlini@oracle.com>
* include/bits/c++config (_GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE,
_GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER): Add.
* src/ios_init.cc (ios_base::Init::~Init): Decorate with the
latter.
* include/tr1_impl/boost_sp_counted_base.h: Likewise.
* include/ext/rc_string_base.h: Likewise.
* include/bits/locale_classes.h: Likewise.
* include/bits/basic_string.h: Likewise.
* include/bits/ios_base.h: Likewise.
* testsuite/27_io/ios_base/cons/assign_neg.cc: Adjust dg-error
line number.
* testsuite/27_io/ios_base/cons/copy_neg.cc: Likewise.
* testsuite/ext/profile/mutex_extensions.cc: Likewise.
Co-Authored-By: Paolo Carlini <paolo.carlini@oracle.com>
From-SVN: r163210
+2010-08-12 Kostya Serebryany <kcc@google.com>
+ Paolo Carlini <paolo.carlini@oracle.com>
+
+ * include/bits/c++config (_GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE,
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER): Add.
+ * src/ios_init.cc (ios_base::Init::~Init): Decorate with the
+ latter.
+ * include/tr1_impl/boost_sp_counted_base.h: Likewise.
+ * include/ext/rc_string_base.h: Likewise.
+ * include/bits/locale_classes.h: Likewise.
+ * include/bits/basic_string.h: Likewise.
+ * include/bits/ios_base.h: Likewise.
+ * testsuite/27_io/ios_base/cons/assign_neg.cc: Adjust dg-error
+ line number.
+ * testsuite/27_io/ios_base/cons/copy_neg.cc: Likewise.
+ * testsuite/ext/profile/mutex_extensions.cc: Likewise.
+
2010-08-11 Paolo Carlini <paolo.carlini@oracle.com>
* include/bits/hashtable.h (_Hashtable<>::erase(const key_type&)):
#ifndef _GLIBCXX_FULLY_DYNAMIC_STRING
if (__builtin_expect(this != &_S_empty_rep(), false))
#endif
- if (__gnu_cxx::__exchange_and_add_dispatch(&this->_M_refcount,
- -1) <= 0)
- _M_destroy(__a);
+ {
+ // Be race-detector-friendly. For more info see bits/c++config.
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&this->_M_refcount)
+ if (__gnu_cxx::__exchange_and_add_dispatch(&this->_M_refcount,
+ -1) <= 0)
+ {
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&this->_M_refcount)
+ _M_destroy(__a);
+ }
+ }
} // XXX MT
void
# define _GLIBCXX_DEPRECATED_ATTR
#endif
+// Macros for race detectors.
+// _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(A) and
+// _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(A) should be used to explain
+// atomic (lock-free) synchronization to race detectors:
+// the race detector will infer a happens-before arc from the former to the
+// latter when they share the same argument pointer.
+//
+// The most frequent use case for these macros (and the only case in the
+// current implementation of the library) is atomic reference counting:
+// void _M_remove_reference()
+// {
+// _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&this->_M_refcount)
+// if (__gnu_cxx::__exchange_and_add_dispatch(&this->_M_refcount, -1) <= 0)
+// {
+// _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&this->_M_refcount)
+// _M_destroy(__a);
+// }
+// }
+// The annotations in this example tell the race detector that all memory
+// accesses occurred when the refcount was positive do not race with
+// memory accesses which occurred after the refcount became zero.
+
+#ifndef _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE
+# define _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(A)
+#endif
+#ifndef _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER
+# define _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(A)
+#endif
+
// Macros for activating various namespace association modes.
// _GLIBCXX_NAMESPACE_ASSOCIATION_DEBUG
// _GLIBCXX_NAMESPACE_ASSOCIATION_PARALLEL
// 0 => OK to delete.
int
_M_remove_reference()
- { return __gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1); }
+ {
+ // Be race-detector-friendly. For more info see bits/c++config.
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount)
+ int __res = __gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1);
+ if (__res == 0)
+ {
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount)
+ }
+ return __res;
+ }
};
_Callback_list* _M_callbacks;
_GLIBCXX_END_NAMESPACE
#endif /* _IOS_BASE_H */
-
void
_M_remove_reference() const throw()
{
+ // Be race-detector-friendly. For more info see bits/c++config.
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount)
if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1)
{
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount)
__try
{ delete this; }
__catch(...)
void
_M_remove_reference() throw()
{
+ // Be race-detector-friendly. For more info see bits/c++config.
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_refcount)
if (__gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1) == 1)
{
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_refcount)
__try
{ delete this; }
__catch(...)
void
_M_dispose()
{
+ // Be race-detector-friendly. For more info see bits/c++config.
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_rep()->_M_info.
+ _M_refcount)
if (__exchange_and_add_dispatch(&_M_rep()->_M_info._M_refcount,
-1) <= 0)
- _M_rep()->_M_destroy(_M_get_allocator());
+ {
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_rep()->_M_info.
+ _M_refcount)
+ _M_rep()->_M_destroy(_M_get_allocator());
+ }
} // XXX MT
bool
// <tr1_impl/boost_sp_counted_base.h> -*- C++ -*-
-// Copyright (C) 2007, 2009 Free Software Foundation, Inc.
+// Copyright (C) 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
void
_M_release() // nothrow
{
+ // Be race-detector-friendly. For more info see bits/c++config.
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_use_count)
if (__gnu_cxx::__exchange_and_add_dispatch(&_M_use_count, -1) == 1)
{
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_use_count)
_M_dispose();
// There must be a memory barrier between dispose() and destroy()
// to ensure that the effects of dispose() are observed in the
_GLIBCXX_WRITE_MEM_BARRIER;
}
+ // Be race-detector-friendly. For more info see bits/c++config.
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_weak_count)
if (__gnu_cxx::__exchange_and_add_dispatch(&_M_weak_count,
-1) == 1)
- _M_destroy();
+ {
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_weak_count)
+ _M_destroy();
+ }
}
}
void
_M_weak_release() // nothrow
{
+ // Be race-detector-friendly. For more info see bits/c++config.
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_M_weak_count)
if (__gnu_cxx::__exchange_and_add_dispatch(&_M_weak_count, -1) == 1)
{
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_M_weak_count)
if (_Mutex_base<_Lp>::_S_need_barriers)
{
// See _M_release(),
// Iostreams base classes -*- C++ -*-
// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
-// 2006, 2007, 2008, 2009
+// 2006, 2007, 2008, 2009, 2010
// Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
ios_base::Init::~Init()
{
+ // Be race-detector-friendly. For more info see bits/c++config.
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&_S_refcount)
if (__gnu_cxx::__exchange_and_add_dispatch(&_S_refcount, -1) == 2)
{
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&_S_refcount)
// Catch any exceptions thrown by basic_ostream::flush()
__try
{
}
// { dg-error "synthesized" "" { target *-*-* } 33 }
// { dg-error "within this context" "" { target *-*-* } 26 }
-// { dg-error "is private" "" { target *-*-* } 779 }
+// { dg-error "is private" "" { target *-*-* } 788 }
// { dg-error "operator=" "" { target *-*-* } 0 }
}
// { dg-error "within this context" "" { target *-*-* } 26 }
// { dg-error "synthesized" "" { target *-*-* } 33 }
-// { dg-error "is private" "" { target *-*-* } 776 }
+// { dg-error "is private" "" { target *-*-* } 785 }
// { dg-error "copy constructor" "" { target *-*-* } 0 }
// -*- C++ -*-
-// Copyright (C) 2006, 2007, 2009 Free Software Foundation, Inc.
+// Copyright (C) 2006, 2007, 2009, 2010 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
#include <vector>
-// { dg-error "Cannot use -D_GLIBCXX_PROFILE with " "" { target *-*-* } 167 }
+// { dg-error "Cannot use -D_GLIBCXX_PROFILE with " "" { target *-*-* } 196 }
projects / thirdparty / gcc.git / commitdiff
