Re: [patch] remove darwin from libgomp's target.

[Andreas Tobler <toa at pop dot agri dot ch>]

Shantonu Sen wrote:
> Here's what I have so far, with the new files as attachments. In 
> particular, I haven't verified that the cancellation point semantics are 
> preserved with respect to the POSIX semaphore version. I also dumped the 
> files in libgomp/config/darwin. A longer term fix would probably involve 
> more autoconf checks, and having this version alongside the POSIX 
> semaphore version in libgomp/config/posix, and using the appropriate 
> version, since they both use POSIX features.
>
> I guess I should get a copyright assignment process going...

Shantonu,

I've taken your work and tried to integrate it into the current 
infrastructure.

Patch attached. (autoheader, autoconf needed in libgomp)

I've ran a build on three platforms to make sure that it still works. 
(darwin-ppc, linux-ppc, sparc-solaris8 multilib)

Darwin-ppc reports the same as your run, 122/5. (the others as well)

Great!!!

Regards,
Andreas


Index: configure.ac
===================================================================
--- configure.ac	(revision 110365)
+++ configure.ac	(working copy)
@@ -165,6 +165,14 @@
 # Check for functions needed.
 AC_CHECK_FUNCS(getloadavg clock_gettime)
 
+# Check for broken semaphore implementation on darwin.
+case "$host" in
+  *-darwin*)
+    AC_DEFINE(HAVE_BROKEN_POSIX_SEMAPHORES, 1,
+	Define if the Posix semaphores do not work on your system)
+    ;;
+esac
+
 # At least for glibc, clock_gettime is in librt.  But don't pull that
 # in if it still doesn't give us the function we want.
 if test $ac_cv_func_clock_gettime = no; then
Index: config/posix/sem.h
===================================================================
--- config/posix/sem.h	(revision 110365)
+++ config/posix/sem.h	(working copy)
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Free Software Foundation, Inc.
+/* Copyright (C) 2005, 2006 Free Software Foundation, Inc.
    Contributed by Richard Henderson <rth@redhat.com>.
 
    This file is part of the GNU OpenMP Library (libgomp).
@@ -46,6 +46,27 @@
 # pragma GCC visibility pop
 #endif
 
+#ifdef HAVE_BROKEN_POSIX_SEMAPHORES
+#include <pthread.h>
+
+struct gomp_sem {
+  pthread_mutex_t	mutex;
+  pthread_cond_t	cond;
+  int			value;
+};
+
+typedef struct gomp_sem gomp_sem_t;
+
+extern void gomp_sem_init (gomp_sem_t *sem, int value);
+
+extern void gomp_sem_wait (gomp_sem_t *sem);
+
+extern void gomp_sem_post (gomp_sem_t *sem);
+
+extern void gomp_sem_destroy (gomp_sem_t *sem);
+
+#else /* HAVE_BROKEN_POSIX_SEMAPHORES  */
+
 typedef sem_t gomp_sem_t;
 
 static inline void gomp_sem_init (gomp_sem_t *sem, int value)
@@ -64,5 +85,5 @@
 {
   sem_destroy (sem);
 }
-
+#endif
 #endif /* GOMP_SEM_H */
Index: config/posix/sem.c
===================================================================
--- config/posix/sem.c	(revision 110365)
+++ config/posix/sem.c	(working copy)
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Free Software Foundation, Inc.
+/* Copyright (C) 2005, 2006 Free Software Foundation, Inc.
    Contributed by Richard Henderson <rth@redhat.com>.
 
    This file is part of the GNU OpenMP Library (libgomp).
@@ -35,7 +35,84 @@
 
 #include "libgomp.h"
 
+#ifdef HAVE_BROKEN_POSIX_SEMAPHORES
+#include <stdlib.h>
 
+void gomp_sem_init (gomp_sem_t *sem, int value)
+{
+  int ret;
+
+  ret = pthread_mutex_init(&sem->mutex, NULL);
+  if(ret) return;
+
+  ret = pthread_cond_init(&sem->cond, NULL);
+  if(ret) return;
+
+  sem->value = value;
+}
+
+void gomp_sem_wait (gomp_sem_t *sem)
+{
+  int ret;
+
+  ret = pthread_mutex_lock(&sem->mutex);
+  if(ret)
+    return;
+
+  if(sem->value > 0) {
+    sem->value--;
+    ret = pthread_mutex_unlock(&sem->mutex);
+
+    return;
+  }
+
+  while(sem->value <= 0) {
+    ret = pthread_cond_wait(&sem->cond, &sem->mutex);
+    if(ret) {
+      pthread_mutex_unlock(&sem->mutex);
+      return;
+    }
+  }
+
+  sem->value--;
+
+  ret = pthread_mutex_unlock(&sem->mutex);
+
+  return;
+}
+
+void gomp_sem_post (gomp_sem_t *sem)
+{
+  int ret;
+
+  ret = pthread_mutex_lock(&sem->mutex);
+  if(ret)
+    return;
+
+  sem->value++;
+
+  ret = pthread_mutex_unlock(&sem->mutex);
+  if(ret)
+    return;
+
+  ret = pthread_cond_signal(&sem->cond);
+
+  return;
+}
+
+void gomp_sem_destroy (gomp_sem_t *sem)
+{
+  int ret;
+
+  ret = pthread_mutex_destroy(&sem->mutex);
+  if(ret)
+    return;
+
+  ret = pthread_cond_destroy(&sem->cond);
+
+  return;
+}
+#else /* HAVE_BROKEN_POSIX_SEMAPHORES  */
 void
 gomp_sem_wait (gomp_sem_t *sem)
 {
@@ -44,3 +121,4 @@
   while (sem_wait (sem) != 0)
     continue;
 }
+#endif