Imported gcc-4.4.3

[msp430-gcc.git] / libgomp / critical.c

diff --git a/libgomp/critical.c b/libgomp/critical.c
new file mode 100644 (file)
index 0000000..daf1ffc
--- /dev/null
+++ b/libgomp/critical.c
@@ -0,0 +1,146 @@
+/* Copyright (C) 2005, 2009 Free Software Foundation, Inc.
+   Contributed by Richard Henderson <rth@redhat.com>.
+
+   This file is part of the GNU OpenMP Library (libgomp).
+
+   Libgomp is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3, or (at your option)
+   any later version.
+
+   Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
+   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+   FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+   more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* This file handles the CRITICAL construct.  */
+
+#include "libgomp.h"
+#include <stdlib.h>
+
+
+static gomp_mutex_t default_lock;
+
+void
+GOMP_critical_start (void)
+{
+  gomp_mutex_lock (&default_lock);
+}
+
+void
+GOMP_critical_end (void)
+{
+  gomp_mutex_unlock (&default_lock);
+}
+
+#ifndef HAVE_SYNC_BUILTINS
+static gomp_mutex_t create_lock_lock;
+#endif
+
+void
+GOMP_critical_name_start (void **pptr)
+{
+  gomp_mutex_t *plock;
+
+  /* If a mutex fits within the space for a pointer, and is zero initialized,
+     then use the pointer space directly.  */
+  if (GOMP_MUTEX_INIT_0
+      && sizeof (gomp_mutex_t) <= sizeof (void *)
+      && __alignof (gomp_mutex_t) <= sizeof (void *))
+    plock = (gomp_mutex_t *)pptr;
+
+  /* Otherwise we have to be prepared to malloc storage.  */
+  else
+    {
+      plock = *pptr;
+
+      if (plock == NULL)
+       {
+#ifdef HAVE_SYNC_BUILTINS
+         gomp_mutex_t *nlock = gomp_malloc (sizeof (gomp_mutex_t));
+         gomp_mutex_init (nlock);
+
+         plock = __sync_val_compare_and_swap (pptr, NULL, nlock);
+         if (plock != NULL)
+           {
+             gomp_mutex_destroy (nlock);
+             free (nlock);
+           }
+         else
+           plock = nlock;
+#else
+         gomp_mutex_lock (&create_lock_lock);
+         plock = *pptr;
+         if (plock == NULL)
+           {
+             plock = gomp_malloc (sizeof (gomp_mutex_t));
+             gomp_mutex_init (plock);
+             __sync_synchronize ();
+             *pptr = plock;
+           }
+         gomp_mutex_unlock (&create_lock_lock);
+#endif
+       }
+    }
+
+  gomp_mutex_lock (plock);
+}
+
+void
+GOMP_critical_name_end (void **pptr)
+{
+  gomp_mutex_t *plock;
+
+  /* If a mutex fits within the space for a pointer, and is zero initialized,
+     then use the pointer space directly.  */
+  if (GOMP_MUTEX_INIT_0
+      && sizeof (gomp_mutex_t) <= sizeof (void *)
+      && __alignof (gomp_mutex_t) <= sizeof (void *))
+    plock = (gomp_mutex_t *)pptr;
+  else
+    plock = *pptr;
+
+  gomp_mutex_unlock (plock);
+}
+
+/* This mutex is used when atomic operations don't exist for the target
+   in the mode requested.  The result is not globally atomic, but works so
+   long as all parallel references are within #pragma omp atomic directives.
+   According to responses received from omp@openmp.org, appears to be within
+   spec.  Which makes sense, since that's how several other compilers 
+   handle this situation as well.  */
+
+static gomp_mutex_t atomic_lock;
+
+void
+GOMP_atomic_start (void)
+{
+  gomp_mutex_lock (&atomic_lock);
+}
+
+void
+GOMP_atomic_end (void)
+{
+  gomp_mutex_unlock (&atomic_lock);
+}
+
+#if !GOMP_MUTEX_INIT_0
+static void __attribute__((constructor))
+initialize_critical (void)
+{
+  gomp_mutex_init (&default_lock);
+  gomp_mutex_init (&atomic_lock);
+#ifndef HAVE_SYNC_BUILTINS
+  gomp_mutex_init (&create_lock_lock);
+#endif
+}
+#endif