PR libstdc++/51798 continued.

2012-02-10  Benjamin Kosnik  <bkoz@redhat.com>
            Jonathan Wakely  <jwakely.gcc@gmail.com>

	PR libstdc++/51798 continued.
	* acinclude.m4 (GLIBCXX_ENABLE_ATOMIC_BUILTINS): Use __atomic_*
	builtins instead of __sync_* builtins for atomic functionality.
	* include/bits/shared_ptr_base.h: Same.
	* include/parallel/compatibility.h: Same.
	* include/profile/impl/profiler_state.h: Same.
	* include/tr1/shared_ptr.h: Same.
	* libsupc++/eh_ptr.cc: Same.
	* libsupc++/eh_throw.cc: Same.
	* libsupc++/eh_tm.cc: Same.
	* libsupc++/guard.cc: Same.
	* configure: Regenerated.
	* testsuite/20_util/shared_ptr/cons/43820_neg.cc: Adjust line numbers.

Co-Authored-By: Jonathan Wakely <jwakely.gcc@gmail.com>

From-SVN: r184110

4 files changed, 38 insertions, 30 deletions

diff --git a/libstdc++-v3/libsupc++/eh_ptr.cc b/libstdc++-v3/libsupc++/eh_ptr.cc
index 684580f..82ebb0b 100644
--- a/libstdc++-v3/libsupc++/eh_ptr.cc
+++ b/libstdc++-v3/libsupc++/eh_ptr.cc
@@ -1,5 +1,5 @@
 // -*- C++ -*- Implement the members of exception_ptr.
-// Copyright (C) 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
+// Copyright (C) 2008, 2009, 2010, 2011, 2012 Free Software Foundation, Inc.
 //
 // This file is part of GCC.
 //
@@ -75,7 +75,7 @@ std::__exception_ptr::exception_ptr::_M_addref() _GLIBCXX_USE_NOEXCEPT
     {
       __cxa_refcounted_exception *eh =
 	__get_refcounted_exception_header_from_obj (_M_exception_object);
-      __sync_add_and_fetch (&eh->referenceCount, 1);
+      __atomic_add_fetch (&eh->referenceCount, 1, __ATOMIC_ACQ_REL);
     }
 }
 
@@ -87,7 +87,7 @@ std::__exception_ptr::exception_ptr::_M_release() _GLIBCXX_USE_NOEXCEPT
     {
       __cxa_refcounted_exception *eh =
 	__get_refcounted_exception_header_from_obj (_M_exception_object);
-      if (__sync_sub_and_fetch (&eh->referenceCount, 1) == 0)
+      if (__atomic_sub_fetch (&eh->referenceCount, 1, __ATOMIC_ACQ_REL) == 0)
         {
 	  if (eh->exc.exceptionDestructor)
 	    eh->exc.exceptionDestructor (_M_exception_object);
@@ -191,7 +191,7 @@ __gxx_dependent_exception_cleanup(_Unwind_Reason_Code code,
 
   __cxa_free_dependent_exception (dep);
 
-  if (__sync_sub_and_fetch (&header->referenceCount, 1) == 0)
+  if (__atomic_sub_fetch (&header->referenceCount, 1, __ATOMIC_ACQ_REL) == 0)
     {
       if (header->exc.exceptionDestructor)
 	header->exc.exceptionDestructor (header + 1);
@@ -210,7 +210,7 @@ std::rethrow_exception(std::exception_ptr ep)
 
   __cxa_dependent_exception *dep = __cxa_allocate_dependent_exception ();
   dep->primaryException = obj;
-  __sync_add_and_fetch (&eh->referenceCount, 1);
+  __atomic_add_fetch (&eh->referenceCount, 1,  __ATOMIC_ACQ_REL);
 
   dep->unexpectedHandler = __unexpected_handler;
   dep->terminateHandler = __terminate_handler;
diff --git a/libstdc++-v3/libsupc++/eh_throw.cc b/libstdc++-v3/libsupc++/eh_throw.cc
index a3d2b0d..de00602 100644
--- a/libstdc++-v3/libsupc++/eh_throw.cc
+++ b/libstdc++-v3/libsupc++/eh_throw.cc
@@ -1,6 +1,6 @@
 // -*- C++ -*- Exception handling routines for throwing.
 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
-// 2011  Free Software Foundation, Inc.
+// 2011, 2012  Free Software Foundation, Inc.
 //
 // This file is part of GCC.
 //
@@ -44,7 +44,7 @@ __gxx_exception_cleanup (_Unwind_Reason_Code code, _Unwind_Exception *exc)
     __terminate (header->exc.terminateHandler);
 
 #if ATOMIC_INT_LOCK_FREE > 1
-  if (__sync_sub_and_fetch (&header->referenceCount, 1) == 0)
+  if (__atomic_sub_fetch (&header->referenceCount, 1, __ATOMIC_ACQ_REL) == 0)
     {
 #endif
       if (header->exc.exceptionDestructor)
diff --git a/libstdc++-v3/libsupc++/eh_tm.cc b/libstdc++-v3/libsupc++/eh_tm.cc
index 1df8644..bd9de6c 100644
--- a/libstdc++-v3/libsupc++/eh_tm.cc
+++ b/libstdc++-v3/libsupc++/eh_tm.cc
@@ -1,5 +1,5 @@
 // -*- C++ -*- Exception handling routines for Transactional Memory.
-// Copyright (C) 2009, 2011 Free Software Foundation, Inc.
+// Copyright (C) 2009, 2011, 2012 Free Software Foundation, Inc.
 //
 // This file is part of GCC.
 //
@@ -46,7 +46,7 @@ free_any_cxa_exception (_Unwind_Exception *eo)
     }
 
 #if __GCC_ATOMIC_INT_LOCK_FREE > 1
-  if (__sync_sub_and_fetch (&h->referenceCount, 1) == 0)
+  if (__atomic_sub_fetch (&h->referenceCount, 1, __ATOMIC_ACQ_REL) == 0)
 #endif
     __cxa_free_exception (h + 1);
 }
diff --git a/libstdc++-v3/libsupc++/guard.cc b/libstdc++-v3/libsupc++/guard.cc
index 643ecd7..b7b8d3f 100644
--- a/libstdc++-v3/libsupc++/guard.cc
+++ b/libstdc++-v3/libsupc++/guard.cc
@@ -1,4 +1,4 @@
-// Copyright (C) 2002, 2004, 2006, 2008, 2009, 2010, 2011
+// Copyright (C) 2002, 2004, 2006, 2008, 2009, 2010, 2011, 2012
 // Free Software Foundation, Inc.
 //  
 // This file is part of GCC.
@@ -239,34 +239,42 @@ namespace __cxxabiv1
       return 0;
 
 # ifdef _GLIBCXX_USE_FUTEX
-    // If __sync_* and futex syscall are supported, don't use any global
+    // If __atomic_* and futex syscall are supported, don't use any global
     // mutex.
     if (__gthread_active_p ())
       {
 	int *gi = (int *) (void *) g;
+	int expected(0);
 	const int guard_bit = _GLIBCXX_GUARD_BIT;
 	const int pending_bit = _GLIBCXX_GUARD_PENDING_BIT;
 	const int waiting_bit = _GLIBCXX_GUARD_WAITING_BIT;
 
 	while (1)
 	  {
-	    int old = __sync_val_compare_and_swap (gi, 0, pending_bit);
-	    if (old == 0)
-	      return 1;	// This thread should do the initialization.
-
-	    if (old == guard_bit)
-	      return 0;	// Already initialized.
-
-	    if (old == pending_bit)
+	    if (__atomic_compare_exchange_n(gi, &expected, pending_bit, true,
+					    __ATOMIC_ACQ_REL, __ATOMIC_RELAXED))
 	      {
-		int newv = old | waiting_bit;
-		if (__sync_val_compare_and_swap (gi, old, newv) != old)
-		  continue;
-
-		old = newv;
+		// This thread should do the initialization.
+		return 1;
 	      }
-
-	    syscall (SYS_futex, gi, _GLIBCXX_FUTEX_WAIT, old, 0);
+	      
+	    if (expected == guard_bit)
+	      {
+		// Already initialized.
+		return 0;	
+	      }
+	     if (expected == pending_bit)
+	       {
+		 int newv = expected | waiting_bit;
+		 if (!__atomic_compare_exchange_n(gi, &expected, newv, true,
+						  __ATOMIC_ACQ_REL, 
+						  __ATOMIC_RELAXED))
+		   continue;
+		 
+		 expected = newv;
+	       }
+
+	    syscall (SYS_futex, gi, _GLIBCXX_FUTEX_WAIT, expected, 0);
 	  }
       }
 # else
@@ -316,13 +324,13 @@ namespace __cxxabiv1
   void __cxa_guard_abort (__guard *g) throw ()
   {
 #ifdef _GLIBCXX_USE_FUTEX
-    // If __sync_* and futex syscall are supported, don't use any global
+    // If __atomic_* and futex syscall are supported, don't use any global
     // mutex.
     if (__gthread_active_p ())
       {
 	int *gi = (int *) (void *) g;
 	const int waiting_bit = _GLIBCXX_GUARD_WAITING_BIT;
-	int old = __sync_lock_test_and_set (gi, 0);
+	int old = __atomic_exchange_n (gi, 0, __ATOMIC_ACQ_REL);
 
 	if ((old & waiting_bit) != 0)
 	  syscall (SYS_futex, gi, _GLIBCXX_FUTEX_WAKE, INT_MAX);
@@ -355,14 +363,14 @@ namespace __cxxabiv1
   void __cxa_guard_release (__guard *g) throw ()
   {
 #ifdef _GLIBCXX_USE_FUTEX
-    // If __sync_* and futex syscall are supported, don't use any global
+    // If __atomic_* and futex syscall are supported, don't use any global
     // mutex.
     if (__gthread_active_p ())
       {
 	int *gi = (int *) (void *) g;
 	const int guard_bit = _GLIBCXX_GUARD_BIT;
 	const int waiting_bit = _GLIBCXX_GUARD_WAITING_BIT;
-	int old = __sync_lock_test_and_set (gi, guard_bit);
+	int old = __atomic_exchange_n (gi, guard_bit, __ATOMIC_ACQ_REL);
 
 	if ((old & waiting_bit) != 0)
 	  syscall (SYS_futex, gi, _GLIBCXX_FUTEX_WAKE, INT_MAX);