Validate acc_device_t uses

Check that function arguments of type acc_device_t
are valid enumeration values in all publicly visible
functions from oacc-init.c.

2019-12-03  Frederik Harwath  <frederik@codesourcery.com>

	libgomp/
	* oacc-init.c (acc_known_device_type): Add function.
	(unknown_device_type_error): Add function.
 	(name_of_acc_device_t): Change to call unknown_device_type_error
	on unknown type.
	(resolve_device): Use acc_known_device_type.
 	(acc_init): Fail if acc_device_t argument is not valid.
 	(acc_shutdown): Likewise.
 	(acc_get_num_devices): Likewise.
 	(acc_set_device_type): Likewise.
	(acc_get_device_num): Likewise.
	(acc_set_device_num): Likewise.
 	(acc_on_device): Add comment that argument validity is not checked.

Reviewed-by: Thomas Schwinge <thomas@codesourcery.com>

From-SVN: r278937

libgomp/ChangeLog

+2019-12-03  Frederik Harwath  <frederik@codesourcery.com>
+
+	* oacc-init.c (acc_known_device_type): Add function.
+	(unknown_device_type_error): Add function.
+	(name_of_acc_device_t): Change to call unknown_device_type_error
+	on unknown type.
+	(resolve_device): Use acc_known_device_type.
+	(acc_init): Fail if acc_device_t argument is not valid.
+	(acc_shutdown): Likewise.
+	(acc_get_num_devices): Likewise.
+	(acc_set_device_type): Likewise.
+	(acc_get_device_num): Likewise.
+	(acc_set_device_num): Likewise.
+	(acc_on_device): Add comment that argument validity is not checked.
+
 2019-12-03  Andrew Stubbs  <ams@codesourcery.com>
 
 	* testsuite/lib/libgomp.exp (offload_target_to_openacc_device_type):

libgomp/oacc-init.c

@@ -82,6 +82,18 @@ goacc_register (struct gomp_device_descr *disp)
   gomp_mutex_unlock (&acc_device_lock);
 }
 
+static bool
+known_device_type_p (acc_device_t d)
+{
+  return d >= 0 && d < _ACC_device_hwm;
+}
+
+static void
+unknown_device_type_error (acc_device_t invalid_type)
+{
+  gomp_fatal ("unknown device type %u", invalid_type);
+}
+
 /* OpenACC names some things a little differently.  */
 
 static const char *
@@ -103,8 +115,9 @@ name_of_acc_device_t (enum acc_device_t type)
     case acc_device_host: return "host";
     case acc_device_not_host: return "not_host";
     case acc_device_nvidia: return "nvidia";
-    default: gomp_fatal ("unknown device type %u", (unsigned) type);
+    default: unknown_device_type_error (type);
     }
+  __builtin_unreachable ();
 }
 
 /* ACC_DEVICE_LOCK must be held before calling this function.  If FAIL_IS_ERROR
@@ -123,7 +136,7 @@ resolve_device (acc_device_t d, bool fail_is_error)
 	if (goacc_device_type)
 	  {
 	    /* Lookup the named device.  */
-	    while (++d != _ACC_device_hwm)
+	    while (known_device_type_p (++d))
 	      if (dispatchers[d]
 		  && !strcasecmp (goacc_device_type,
 				  get_openacc_name (dispatchers[d]->name))
@@ -147,7 +160,7 @@ resolve_device (acc_device_t d, bool fail_is_error)
 
     case acc_device_not_host:
       /* Find the first available device after acc_device_not_host.  */
-      while (++d != _ACC_device_hwm)
+      while (known_device_type_p (++d))
 	if (dispatchers[d] && dispatchers[d]->get_num_devices_func () > 0)
 	  goto found;
       if (d_arg == acc_device_default)
@@ -168,7 +181,7 @@ resolve_device (acc_device_t d, bool fail_is_error)
       break;
 
     default:
-      if (d > _ACC_device_hwm)
+      if (!known_device_type_p (d))
 	{
 	  if (fail_is_error)
 	    goto unsupported_device;
@@ -505,6 +518,9 @@ goacc_attach_host_thread_to_device (int ord)
 void
 acc_init (acc_device_t d)
 {
+  if (!known_device_type_p (d))
+    unknown_device_type_error (d);
+
   gomp_init_targets_once ();
 
   gomp_mutex_lock (&acc_device_lock);
@@ -519,6 +535,9 @@ ialias (acc_init)
 void
 acc_shutdown (acc_device_t d)
 {
+  if (!known_device_type_p (d))
+    unknown_device_type_error (d);
+
   gomp_init_targets_once ();
 
   gomp_mutex_lock (&acc_device_lock);
@@ -533,6 +552,9 @@ ialias (acc_shutdown)
 int
 acc_get_num_devices (acc_device_t d)
 {
+  if (!known_device_type_p (d))
+    unknown_device_type_error (d);
+
   int n = 0;
   struct gomp_device_descr *acc_dev;
 
@@ -564,6 +586,9 @@ ialias (acc_get_num_devices)
 void
 acc_set_device_type (acc_device_t d)
 {
+  if (!known_device_type_p (d))
+    unknown_device_type_error (d);
+
   struct gomp_device_descr *base_dev, *acc_dev;
   struct goacc_thread *thr = goacc_thread ();
 
@@ -647,12 +672,12 @@ ialias (acc_get_device_type)
 int
 acc_get_device_num (acc_device_t d)
 {
+  if (!known_device_type_p (d))
+    unknown_device_type_error (d);
+
   const struct gomp_device_descr *dev;
   struct goacc_thread *thr = goacc_thread ();
 
-  if (d >= _ACC_device_hwm)
-    gomp_fatal ("unknown device type %u", (unsigned) d);
-
   acc_prof_info prof_info;
   acc_api_info api_info;
   bool profiling_p = GOACC_PROFILING_SETUP_P (thr, &prof_info, &api_info);
@@ -682,6 +707,9 @@ ialias (acc_get_device_num)
 void
 acc_set_device_num (int ord, acc_device_t d)
 {
+  if (!known_device_type_p (d))
+    unknown_device_type_error (d);
+
   struct gomp_device_descr *base_dev, *acc_dev;
   int num_devices;
 
@@ -728,7 +756,10 @@ ialias (acc_set_device_num)
    version.
 
    Compile this with optimization, so that the compiler expands
-   this, rather than generating infinitely recursive code.  */
+   this, rather than generating infinitely recursive code.
+
+   The function just forwards its argument to __builtin_acc_on_device.  It does
+   not verify that the argument is a valid acc_device_t enumeration value.  */
 
 int __attribute__ ((__optimize__ ("O2")))
 acc_on_device (acc_device_t dev)