Backported r185231 from trunk to google/gcc-4_7. (issue 6888044)

Index: gcc/ChangeLog.google-4_7
===================================================================
--- gcc/ChangeLog.google-4_7	(revision 194106)
+++ gcc/ChangeLog.google-4_7	(working copy)
@@ -1,3 +1,23 @@ 
+2012-12-03  Ahmad Sharif <asharif@google.com>
+
+	Backport r185231 from trunk.
+
+	2012-03-12  Richard Guenther  <rguenther@suse.de>
+
+	* gthr.h (__GTHREAD_MUTEX_INIT_FUNCTION): Adjust specification.
+	* gthr-posix.h (__GTHREAD_MUTEX_INIT_FUNCTION): Define.
+	(__gthread_mutex_init_function): New function.
+	* gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Define.
+
+	PR gcov/49484
+	* libgcov.c: Include gthr.h.
+	(__gcov_flush_mx): New global variable.
+	(init_mx, init_mx_once): New functions.
+	(__gcov_flush): Protect self with a mutex.
+	(__gcov_fork): Re-initialize mutex after forking.
+	* unwind-dw2-fde.c: Change condition under which to use
+	__GTHREAD_MUTEX_INIT_FUNCTION.
+
  2010-12-01  Xinliang David Li  <davidxl@google.com>

  	Backport r194038 from trunk

Property changes on: gcc/testsuite/gcc.target/powerpc/ppc-round.c
___________________________________________________________________
Modified: svn:mergeinfo
    Merged /trunk/gcc/testsuite/gcc.target/powerpc/ppc-round.c:r185231

Index: libgcc/gthr-posix.h
===================================================================
--- libgcc/gthr-posix.h	(revision 194106)
+++ libgcc/gthr-posix.h	(working copy)
@@ -63,6 +63,7 @@ 
  #define __GTHREAD_HAS_COND	1

  #define __GTHREAD_MUTEX_INIT PTHREAD_MUTEX_INITIALIZER
+#define __GTHREAD_MUTEX_INIT_FUNCTION __gthread_mutex_init_function
  #define __GTHREAD_ONCE_INIT PTHREAD_ONCE_INIT
  #if defined(PTHREAD_RECURSIVE_MUTEX_INITIALIZER)
  #define __GTHREAD_RECURSIVE_MUTEX_INIT PTHREAD_RECURSIVE_MUTEX_INITIALIZER
@@ -754,6 +755,14 @@ 
  #endif

  static inline int
+__gthread_mutex_init_function (__gthread_mutex_t *__mutex)
+{
+  if (__gthread_active_p ())
+    return __gthrw_(pthread_mutex_init) (__mutex, NULL);
+  return 0;
+}
+
+static inline int
  __gthread_mutex_destroy (__gthread_mutex_t *__mutex)
  {
    if (__gthread_active_p ())
Index: libgcc/gthr.h
===================================================================
--- libgcc/gthr.h	(revision 194106)
+++ libgcc/gthr.h	(working copy)
@@ -52,11 +52,12 @@ 
       		to initialize __gthread_mutex_t to get a fast
  		non-recursive mutex.
       __GTHREAD_MUTEX_INIT_FUNCTION
-     		some systems can't initialize a mutex without a
-		function call.  On such systems, define this to a
-		function which looks like this:
+		to initialize __gthread_mutex_t to get a fast
+		non-recursive mutex.
+		Define this to a function which looks like this:
  		  void __GTHREAD_MUTEX_INIT_FUNCTION (__gthread_mutex_t *)
-		Don't define __GTHREAD_MUTEX_INIT in this case
+     		Some systems can't initialize a mutex without a
+		function call.  Don't define __GTHREAD_MUTEX_INIT in this case.
       __GTHREAD_RECURSIVE_MUTEX_INIT
       __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION
       		as above, but for a recursive mutex.
Index: libgcc/gthr-single.h
===================================================================
--- libgcc/gthr-single.h	(revision 194106)
+++ libgcc/gthr-single.h	(working copy)
@@ -36,6 +36,7 @@ 

  #define __GTHREAD_ONCE_INIT 0
  #define __GTHREAD_MUTEX_INIT 0
+#define __GTHREAD_MUTEX_INIT_FUNCTION (mx)
  #define __GTHREAD_RECURSIVE_MUTEX_INIT 0

  #define UNUSED __attribute__((unused))
Index: libgcc/libgcov.c
===================================================================
--- libgcc/libgcov.c	(revision 194106)
+++ libgcc/libgcov.c	(working copy)
@@ -48,6 +48,7 @@ 
  #include "tm.h"
  #endif /* __KERNEL__ */
  #include "libgcc_tm.h"
+#include "gthr.h"

  #if 1
  #define THREAD_PREFIX __thread
@@ -759,6 +760,25 @@ 
    info->version = 0;
  }

+#ifdef __GTHREAD_MUTEX_INIT
+ATTRIBUTE_HIDDEN __gthread_mutex_t __gcov_flush_mx = __GTHREAD_MUTEX_INIT;
+#define init_mx_once()
+#else
+__gthread_mutex_t __gcov_flush_mx ATTRIBUTE_HIDDEN;
+
+static void
+init_mx (void)
+{
+  __GTHREAD_MUTEX_INIT_FUNCTION (&mx);
+}
+static void
+init_mx_once (void)
+{
+  static __gthread_once_t once = __GTHREAD_ONCE_INIT;
+  __gthread_once (&once, init_mx);
+}
+#endif
+
  /* Called before fork or exec - write out profile information gathered so
     far and reset it to zero.  This avoids duplication or loss of the
     profile information gathered so far.  */
@@ -766,8 +786,13 @@ 
  void
  __gcov_flush (void)
  {
+  init_mx_once ();
+  __gthread_mutex_lock (&__gcov_flush_mx);
+
    gcov_exit ();
    gcov_clear ();
+
+  __gthread_mutex_unlock (&__gcov_flush_mx);
  }

  #else /* __GCOV_KERNEL__ */
@@ -1836,8 +1861,13 @@ 
  pid_t
  __gcov_fork (void)
  {
+  pid_t pid;
+  extern __gthread_mutex_t __gcov_flush_mx;
    __gcov_flush ();
-  return fork ();
+  pid = fork ();
+  if (pid == 0)
+    __GTHREAD_MUTEX_INIT_FUNCTION (&__gcov_flush_mx);
+  return pid;
  }
  #endif

Index: libgcc/ChangeLog
===================================================================
--- libgcc/ChangeLog	(revision 194106)
+++ libgcc/ChangeLog	(working copy)
@@ -1,3 +1,19 @@ 
+2012-03-12  Richard Guenther  <rguenther@suse.de>
+
+	* gthr.h (__GTHREAD_MUTEX_INIT_FUNCTION): Adjust specification.
+	* gthr-posix.h (__GTHREAD_MUTEX_INIT_FUNCTION): Define.
+	(__gthread_mutex_init_function): New function.
+	* gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Define.
+
+	PR gcov/49484
+	* libgcov.c: Include gthr.h.
+	(__gcov_flush_mx): New global variable.
+	(init_mx, init_mx_once): New functions.
+	(__gcov_flush): Protect self with a mutex.
+	(__gcov_fork): Re-initialize mutex after forking.
+	* unwind-dw2-fde.c: Change condition under which to use
+	__GTHREAD_MUTEX_INIT_FUNCTION.
+
  2012-10-06  Mark Kettenis  <kettenis@openbsd.org>

  	* config.host (*-*-openbsd*): Add t-eh-dw2-dip to tmake_file.
Index: libgcc/unwind-dw2-fde.c
===================================================================
--- libgcc/unwind-dw2-fde.c	(revision 194106)
+++ libgcc/unwind-dw2-fde.c	(working copy)
@@ -47,11 +47,10 @@ 

  #ifdef __GTHREAD_MUTEX_INIT
  static __gthread_mutex_t object_mutex = __GTHREAD_MUTEX_INIT;
+#define init_object_mutex_once()
  #else
  static __gthread_mutex_t object_mutex;
-#endif

-#ifdef __GTHREAD_MUTEX_INIT_FUNCTION
  static void
  init_object_mutex (void)
  {
@@ -64,8 +63,6 @@ 
    static __gthread_once_t once = __GTHREAD_ONCE_INIT;
    __gthread_once (&once, init_object_mutex);
  }
-#else
-#define init_object_mutex_once()
  #endif

  /* Called from crtbegin.o to register the unwind info for an object.  */