[PR88370] acc_get_cuda_stream/acc_set_cuda_stream: acc_async_sync, acc_async_noval

Per my reading of the OpenACC specification (and as supported by secondary
documentation, such as code examples, or presentations), it's valid to call
"acc_get_cuda_stream"/"acc_set_cuda_stream" also with "acc_async_sync",
"acc_async_noval" arguments, not just with the nonnegative values as currently
implemented.

	libgomp/
	PR libgomp/88370
	* libgomp.texi (acc_get_current_cuda_context, acc_get_cuda_stream)
	(acc_set_cuda_stream): Clarify.
	* oacc-cuda.c (acc_get_cuda_stream, acc_set_cuda_stream): Use
	"async_valid_p".
	* plugin/plugin-nvptx.c (nvptx_set_cuda_stream): Refuse "async ==
	acc_async_sync".
	* testsuite/libgomp.oacc-c-c++-common/acc_set_cuda_stream-1.c: New file.
	* testsuite/libgomp.oacc-c-c++-common/async_queue-1.c: Likewise.
	* testsuite/libgomp.oacc-c-c++-common/lib-84.c: Update.
	* testsuite/libgomp.oacc-c-c++-common/lib-85.c: Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@267147 138bc75d-0d04-0410-961f-82ee72b054a4

4 files changed, 187 insertions, 10 deletions

diff --git a/libgomp/testsuite/libgomp.oacc-c-c++-common/acc_set_cuda_stream-1.c b/libgomp/testsuite/libgomp.oacc-c-c++-common/acc_set_cuda_stream-1.c
new file mode 100644
index 00000000000..93981ff5cb7
--- /dev/null
+++ b/libgomp/testsuite/libgomp.oacc-c-c++-common/acc_set_cuda_stream-1.c
@@ -0,0 +1,42 @@
+/* Verify expected nvptx plugin behavior for "acc_set_cuda_stream" for
+   "acc_async_sync".  */
+
+/* { dg-do run { target openacc_nvidia_accel_selected } } */
+/* { dg-set-target-env-var GOMP_DEBUG "1" } */
+
+#undef NDEBUG
+#include <assert.h>
+#include <openacc.h>
+
+int main(void)
+{
+  int async = 42;
+
+  /* Initialize.  */
+#pragma acc parallel async(acc_async_sync)
+      ;
+#pragma acc parallel async(async)
+      ;
+#pragma acc wait
+
+  void *cuda_stream_sync = acc_get_cuda_stream (acc_async_sync);
+  assert (cuda_stream_sync == NULL);
+  void *cuda_stream_async = acc_get_cuda_stream (async);
+  assert (cuda_stream_async != NULL);
+  int ret = acc_set_cuda_stream (acc_async_sync, cuda_stream_async);
+  assert (ret == 0);
+  void *cuda_stream_sync_ = acc_get_cuda_stream (acc_async_sync);
+  assert (cuda_stream_sync_ == cuda_stream_sync);
+  void *cuda_stream_async_ = acc_get_cuda_stream (async);
+  assert (cuda_stream_async_ == cuda_stream_async);
+
+#pragma acc parallel async(acc_async_sync)
+      ;
+#pragma acc parallel async(async)
+      ;
+#pragma acc wait
+
+  return 0;
+}
+
+/* { dg-output "Refusing request to set CUDA stream associated with \"acc_async_sync\"" } */
diff --git a/libgomp/testsuite/libgomp.oacc-c-c++-common/async_queue-1.c b/libgomp/testsuite/libgomp.oacc-c-c++-common/async_queue-1.c
new file mode 100644
index 00000000000..48e1846a36e
--- /dev/null
+++ b/libgomp/testsuite/libgomp.oacc-c-c++-common/async_queue-1.c
@@ -0,0 +1,97 @@
+/* Test mapping of async values to specific underlying queues.  */
+
+#undef NDEBUG
+#include <assert.h>
+#include <openacc.h>
+
+/* This is implemented in terms of the "acc_get_cuda_stream" interface.  */
+
+struct
+{
+  int async;
+  void *cuda_stream;
+} queues[] = { { acc_async_sync, NULL },
+	       { acc_async_noval, NULL },
+	       { 0, NULL },
+	       { 1, NULL },
+	       { 2, NULL },
+	       { 36, NULL },
+	       { 1982, NULL } };
+const size_t queues_n = sizeof queues / sizeof queues[0];
+
+int main(void)
+{
+  /* Explicitly initialize: it's not clear whether the following OpenACC
+     runtime library calls implicitly initialize;
+     <https://github.com/OpenACC/openacc-spec/issues/102>.  */
+  acc_device_t d;
+#if defined ACC_DEVICE_TYPE_nvidia
+  d = acc_device_nvidia;
+#elif defined ACC_DEVICE_TYPE_host
+  d = acc_device_host;
+#else
+# error Not ported to this ACC_DEVICE_TYPE
+#endif
+  acc_init (d);
+
+  for (size_t i = 0; i < queues_n; ++i)
+    {
+      /* Before actually being used, there are all NULL.  */
+      queues[i].cuda_stream = acc_get_cuda_stream (queues[i].async);
+      assert (queues[i].cuda_stream == NULL);
+    }
+
+  for (size_t i = 0; i < queues_n; ++i)
+    {
+      /* Use the queue to initialize it.  */
+#pragma acc parallel async(queues[i].async)
+      ;
+#pragma acc wait
+
+      /* Verify CUDA stream used.  */
+      queues[i].cuda_stream = acc_get_cuda_stream (queues[i].async);
+#if defined ACC_DEVICE_TYPE_nvidia
+      /* "acc_async_sync" maps to the NULL CUDA default stream.  */
+      if (queues[i].async == acc_async_sync)
+	assert (queues[i].cuda_stream == NULL);
+      else
+	assert (queues[i].cuda_stream != NULL);
+#elif defined ACC_DEVICE_TYPE_host
+      /* For "acc_device_host" there are no CUDA streams.  */
+      assert (queues[i].cuda_stream == NULL);
+#else
+# error Not ported to this ACC_DEVICE_TYPE
+#endif
+    }
+
+  /* Verify same results.  */
+  for (size_t i = 0; i < queues_n; ++i)
+    {
+      void *cuda_stream;
+
+      cuda_stream = acc_get_cuda_stream (queues[i].async);
+      assert (cuda_stream == queues[i].cuda_stream);
+
+#pragma acc parallel async(queues[i].async)
+      ;
+#pragma acc wait
+
+      cuda_stream = acc_get_cuda_stream (queues[i].async);
+      assert (cuda_stream == queues[i].cuda_stream);
+    }
+
+  /* Verify individual underlying queues are all different.  */
+  for (size_t i = 0; i < queues_n; ++i)
+    {
+      if (queues[i].cuda_stream == NULL)
+	continue;
+      for (size_t j = i + 1; j < queues_n; ++j)
+	{
+	  if (queues[j].cuda_stream == NULL)
+	    continue;
+	  assert (queues[j].cuda_stream != queues[i].cuda_stream);
+	}
+    }
+
+  return 0;
+}
diff --git a/libgomp/testsuite/libgomp.oacc-c-c++-common/lib-84.c b/libgomp/testsuite/libgomp.oacc-c-c++-common/lib-84.c
index 786b908f755..d793c743630 100644
--- a/libgomp/testsuite/libgomp.oacc-c-c++-common/lib-84.c
+++ b/libgomp/testsuite/libgomp.oacc-c-c++-common/lib-84.c
@@ -7,6 +7,14 @@
 #include <openacc.h>
 #include <cuda.h>
 
+#if !defined __cplusplus
+# undef static_assert
+# define static_assert _Static_assert
+#endif
+
+static_assert (acc_async_sync == -2, "acc_async_sync?");
+static_assert (acc_async_noval == -1, "acc_async_noval?");
+
 int
 main (int argc, char **argv)
 {
@@ -20,9 +28,11 @@ main (int argc, char **argv)
 
   (void) acc_get_device_num (acc_device_nvidia);
 
-  streams = (CUstream *) malloc (N * sizeof (void *));
+  streams = (CUstream *) malloc ((2 + N) * sizeof (void *));
+  streams += 2;
+  /* "streams[i]" is valid for i in [acc_async_sync..N).  */
 
-  for (i = 0; i < N; i++)
+  for (i = acc_async_sync; i < N; i++)
     {
       streams[i] = (CUstream) acc_get_cuda_stream (i);
       if (streams[i] != NULL)
@@ -35,11 +45,20 @@ main (int argc, char **argv)
 	  abort ();
 	}
 
-        if (!acc_set_cuda_stream (i, streams[i]))
-	  abort ();
+      int ret = acc_set_cuda_stream (i, streams[i]);
+      if (i == acc_async_sync)
+	{
+	  if (ret == 1)
+	    abort ();
+	}
+      else
+	{
+	  if (ret != 1)
+	    abort ();
+	}
     }
 
-  for (i = 0; i < N; i++)
+  for (i = acc_async_sync; i < N; i++)
     {
       int j;
       int cnt;
@@ -48,7 +67,7 @@ main (int argc, char **argv)
 
       s = streams[i];
 
-      for (j = 0; j < N; j++)
+      for (j = acc_async_sync; j < N; j++)
 	{
 	  if (s == streams[j])
 	    cnt++;
diff --git a/libgomp/testsuite/libgomp.oacc-c-c++-common/lib-85.c b/libgomp/testsuite/libgomp.oacc-c-c++-common/lib-85.c
index cf925a7b002..141c83b53dd 100644
--- a/libgomp/testsuite/libgomp.oacc-c-c++-common/lib-85.c
+++ b/libgomp/testsuite/libgomp.oacc-c-c++-common/lib-85.c
@@ -7,6 +7,14 @@
 #include <stdio.h>
 #include <cuda.h>
 
+#if !defined __cplusplus
+# undef static_assert
+# define static_assert _Static_assert
+#endif
+
+static_assert (acc_async_sync == -2, "acc_async_sync?");
+static_assert (acc_async_noval == -1, "acc_async_noval?");
+
 int
 main (int argc, char **argv)
 {
@@ -20,9 +28,11 @@ main (int argc, char **argv)
 
   (void) acc_get_device_num (acc_device_nvidia);
 
-  streams = (CUstream *) malloc (N * sizeof (void *));
+  streams = (CUstream *) malloc ((2 + N) * sizeof (void *));
+  streams += 2;
+  /* "streams[i]" is valid for i in [acc_async_sync..N).  */
 
-  for (i = 0; i < N; i++)
+  for (i = acc_async_sync; i < N; i++)
     {
       streams[i] = (CUstream) acc_get_cuda_stream (i);
       if (streams[i] != NULL)
@@ -35,8 +45,17 @@ main (int argc, char **argv)
 	  abort ();
 	}
 
-        if (!acc_set_cuda_stream (i, streams[i]))
-	  abort ();
+      int ret = acc_set_cuda_stream (i, streams[i]);
+      if (i == acc_async_sync)
+	{
+	  if (ret == 1)
+	    abort ();
+	}
+      else
+	{
+	  if (ret != 1)
+	    abort ();
+	}
     }
 
   s = NULL;