OSDN Git Service

2008-02-04 Richard Guenther <rguenther@suse.de>
[pf3gnuchains/gcc-fork.git] / gcc / gthr-posix.h
index df03947..ad6822e 100644 (file)
@@ -1,6 +1,6 @@
 /* Threads compatibility routines for libgcc2 and libobjc.  */
 /* Compile this one with gcc.  */
-/* Copyright (C) 1997, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
+/* Copyright (C) 1997, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
    Free Software Foundation, Inc.
 
 This file is part of GCC.
@@ -36,7 +36,7 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
 #define __GTHREADS 1
 
 /* Some implementations of <pthread.h> require this to be defined.  */
-#ifndef _REENTRANT
+#if !defined(_REENTRANT) && defined(__osf__)
 #define _REENTRANT 1
 #endif
 
@@ -47,6 +47,11 @@ typedef pthread_key_t __gthread_key_t;
 typedef pthread_once_t __gthread_once_t;
 typedef pthread_mutex_t __gthread_mutex_t;
 typedef pthread_mutex_t __gthread_recursive_mutex_t;
+typedef pthread_cond_t __gthread_cond_t;
+
+/* POSIX like conditional variables are supported.  Please look at comments
+   in gthr.h for details. */
+#define __GTHREAD_HAS_COND     1       
 
 #define __GTHREAD_MUTEX_INIT PTHREAD_MUTEX_INITIALIZER
 #define __GTHREAD_ONCE_INIT PTHREAD_ONCE_INIT
@@ -57,32 +62,40 @@ typedef pthread_mutex_t __gthread_recursive_mutex_t;
 #else
 #define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_recursive_mutex_init_function
 #endif
+#define __GTHREAD_COND_INIT PTHREAD_COND_INITIALIZER
 
 #if SUPPORTS_WEAK && GTHREAD_USE_WEAK
-# define __gthrw2(name,name2) \
-  static __typeof(name) __gthrw_ ## name __attribute__ ((__weakref__(#name2)));
+# ifndef __gthrw_pragma
+#  define __gthrw_pragma(pragma)
+# endif
+# define __gthrw2(name,name2,type) \
+  static __typeof(type) name __attribute__ ((__weakref__(#name2))); \
+  __gthrw_pragma(weak type)
 # define __gthrw_(name) __gthrw_ ## name
 #else
-# define __gthrw2(name,name2)
+# define __gthrw2(name,name2,type)
 # define __gthrw_(name) name
 #endif
 
 /* Typically, __gthrw_foo is a weak reference to symbol foo.  */
-#define __gthrw(name) __gthrw2(name,name)
+#define __gthrw(name) __gthrw2(__gthrw_ ## name,name,name)
 
 /* On Tru64, /usr/include/pthread.h uses #pragma extern_prefix "__" to
    map a subset of the POSIX pthread API to mangled versions of their
    names.  */
 #if defined(__osf__) && defined(_PTHREAD_USE_MANGLED_NAMES_)
-__gthrw2(pthread_once,__pthread_once)
-__gthrw2(pthread_getspecific,__pthread_getspecific)
-__gthrw2(pthread_setspecific,__pthread_setspecific)
-__gthrw2(pthread_create,__pthread_create)
-__gthrw2(pthread_cancel,__pthread_cancel)
-__gthrw2(pthread_mutex_lock,__pthread_mutex_lock)
-__gthrw2(pthread_mutex_trylock,__pthread_mutex_trylock)
-__gthrw2(pthread_mutex_unlock,__pthread_mutex_unlock)
-__gthrw2(pthread_mutex_init,__pthread_mutex_init)
+#define __gthrw3(name) __gthrw2(__gthrw_ ## name, __ ## name, name)
+__gthrw3(pthread_once)
+__gthrw3(pthread_getspecific)
+__gthrw3(pthread_setspecific)
+__gthrw3(pthread_create)
+__gthrw3(pthread_cancel)
+__gthrw3(pthread_mutex_lock)
+__gthrw3(pthread_mutex_trylock)
+__gthrw3(pthread_mutex_unlock)
+__gthrw3(pthread_mutex_init)
+__gthrw3(pthread_cond_broadcast)
+__gthrw3(pthread_cond_wait)
 #else
 __gthrw(pthread_once)
 __gthrw(pthread_getspecific)
@@ -93,6 +106,8 @@ __gthrw(pthread_mutex_lock)
 __gthrw(pthread_mutex_trylock)
 __gthrw(pthread_mutex_unlock)
 __gthrw(pthread_mutex_init)
+__gthrw(pthread_cond_broadcast)
+__gthrw(pthread_cond_wait)
 #endif
 
 __gthrw(pthread_key_create)
@@ -105,20 +120,16 @@ __gthrw(pthread_mutexattr_destroy)
 #if defined(_LIBOBJC) || defined(_LIBOBJC_WEAK)
 /* Objective-C.  */
 #if defined(__osf__) && defined(_PTHREAD_USE_MANGLED_NAMES_)
-__gthrw2(pthread_cond_broadcast,__pthread_cond_broadcast)
-__gthrw2(pthread_cond_destroy,__pthread_cond_destroy)
-__gthrw2(pthread_cond_init,__pthread_cond_init)
-__gthrw2(pthread_cond_signal,__pthread_cond_signal)
-__gthrw2(pthread_cond_wait,__pthread_cond_wait)
-__gthrw2(pthread_exit,__pthread_exit)
-__gthrw2(pthread_mutex_destroy,__pthread_mutex_destroy)
-__gthrw2(pthread_self,__pthread_self)
+__gthrw3(pthread_cond_destroy)
+__gthrw3(pthread_cond_init)
+__gthrw3(pthread_cond_signal)
+__gthrw3(pthread_exit)
+__gthrw3(pthread_mutex_destroy)
+__gthrw3(pthread_self)
 #else
-__gthrw(pthread_cond_broadcast)
 __gthrw(pthread_cond_destroy)
 __gthrw(pthread_cond_init)
 __gthrw(pthread_cond_signal)
-__gthrw(pthread_cond_wait)
 __gthrw(pthread_exit)
 __gthrw(pthread_mutex_destroy)
 __gthrw(pthread_self)
@@ -141,6 +152,59 @@ __gthrw(pthread_setschedparam)
 
 #if SUPPORTS_WEAK && GTHREAD_USE_WEAK
 
+/* On Solaris 2.6 up to 9, the libc exposes a POSIX threads interface even if
+   -pthreads is not specified.  The functions are dummies and most return an
+   error value.  However pthread_once returns 0 without invoking the routine
+   it is passed so we cannot pretend that the interface is active if -pthreads
+   is not specified.  On Solaris 2.5.1, the interface is not exposed at all so
+   we need to play the usual game with weak symbols.  On Solaris 10 and up, a
+   working interface is always exposed.  */
+
+#if defined(__sun) && defined(__svr4__)
+
+static volatile int __gthread_active = -1;
+
+static void
+__gthread_trigger (void)
+{
+  __gthread_active = 1;
+}
+
+static inline int
+__gthread_active_p (void)
+{
+  static pthread_mutex_t __gthread_active_mutex = PTHREAD_MUTEX_INITIALIZER;
+  static pthread_once_t __gthread_active_once = PTHREAD_ONCE_INIT;
+
+  /* Avoid reading __gthread_active twice on the main code path.  */
+  int __gthread_active_latest_value = __gthread_active;
+
+  /* This test is not protected to avoid taking a lock on the main code
+     path so every update of __gthread_active in a threaded program must
+     be atomic with regard to the result of the test.  */
+  if (__builtin_expect (__gthread_active_latest_value < 0, 0))
+    {
+      if (__gthrw_(pthread_once))
+       {
+         /* If this really is a threaded program, then we must ensure that
+            __gthread_active has been set to 1 before exiting this block.  */
+         __gthrw_(pthread_mutex_lock) (&__gthread_active_mutex);
+         __gthrw_(pthread_once) (&__gthread_active_once, __gthread_trigger);
+         __gthrw_(pthread_mutex_unlock) (&__gthread_active_mutex);
+       }
+
+      /* Make sure we'll never enter this block again.  */
+      if (__gthread_active < 0)
+       __gthread_active = 0;
+
+      __gthread_active_latest_value = __gthread_active;
+    }
+
+  return __gthread_active_latest_value != 0;
+}
+
+#else /* not Solaris */
+
 static inline int
 __gthread_active_p (void)
 {
@@ -149,14 +213,85 @@ __gthread_active_p (void)
   return __gthread_active_ptr != 0;
 }
 
+#endif /* Solaris */
+
 #else /* not SUPPORTS_WEAK */
 
+/* Similar to Solaris, HP-UX 11 for PA-RISC provides stubs for pthread
+   calls in shared flavors of the HP-UX C library.  Most of the stubs
+   have no functionality.  The details are described in the "libc cumulative
+   patch" for each subversion of HP-UX 11.  There are two special interfaces
+   provided for checking whether an application is linked to a pthread
+   library or not.  However, these interfaces aren't available in early
+   libc versions.  We also can't use pthread_once as some libc versions
+   call the init function.  So, we use pthread_create to check whether it
+   is possible to create a thread or not.  The stub implementation returns
+   the error number ENOSYS.  */
+
+#if defined(__hppa__) && defined(__hpux__)
+
+#include <errno.h>
+
+static volatile int __gthread_active = -1;
+
+static void *
+__gthread_start (void *arg __attribute__((unused)))
+{
+  return NULL;
+}
+
+static void __gthread_active_init (void) __attribute__((noinline));
+static void
+__gthread_active_init (void)
+{
+  static pthread_mutex_t __gthread_active_mutex = PTHREAD_MUTEX_INITIALIZER;
+  pthread_t t;
+  pthread_attr_t a;
+  int result;
+
+  __gthrw_(pthread_mutex_lock) (&__gthread_active_mutex);
+  if (__gthread_active < 0)
+    {
+      __gthrw_(pthread_attr_init) (&a);
+      __gthrw_(pthread_attr_setdetachstate) (&a, PTHREAD_CREATE_DETACHED);
+      result = __gthrw_(pthread_create) (&t, &a, __gthread_start, NULL);
+      if (result != ENOSYS)
+       __gthread_active = 1;
+      else
+       __gthread_active = 0;
+      __gthrw_(pthread_attr_destroy) (&a);
+    }
+  __gthrw_(pthread_mutex_unlock) (&__gthread_active_mutex);
+}
+
+static inline int
+__gthread_active_p (void)
+{
+  /* Avoid reading __gthread_active twice on the main code path.  */
+  int __gthread_active_latest_value = __gthread_active;
+
+  /* This test is not protected to avoid taking a lock on the main code
+     path so every update of __gthread_active in a threaded program must
+     be atomic with regard to the result of the test.  */
+  if (__builtin_expect (__gthread_active_latest_value < 0, 0))
+    {
+      __gthread_active_init ();
+      __gthread_active_latest_value = __gthread_active;
+    }
+
+  return __gthread_active_latest_value != 0;
+}
+
+#else /* not hppa-hpux */
+
 static inline int
 __gthread_active_p (void)
 {
   return 1;
 }
 
+#endif /* hppa-hpux */
+
 #endif /* SUPPORTS_WEAK */
 
 #ifdef _LIBOBJC
@@ -608,6 +743,25 @@ __gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
   return __gthread_mutex_unlock (mutex);
 }
 
+static inline int
+__gthread_cond_broadcast (__gthread_cond_t *cond)
+{
+  return __gthrw_(pthread_cond_broadcast) (cond);
+}
+
+static inline int
+__gthread_cond_wait (__gthread_cond_t *cond, __gthread_mutex_t *mutex)
+{
+  return __gthrw_(pthread_cond_wait) (cond, mutex);
+}
+
+static inline int
+__gthread_cond_wait_recursive (__gthread_cond_t *cond,
+                              __gthread_recursive_mutex_t *mutex)
+{
+  return __gthread_cond_wait (cond, mutex);
+}
+
 #endif /* _LIBOBJC */
 
 #endif /* ! GCC_GTHR_POSIX_H */