[OpenMP] Implement omp_get_uid_from_device() / omp_get_device_from_uid() (#164392)

Use the implementation in libomptarget. If libomptarget is not
available, always return the UID / device number of the host / the
initial device.

1 files changed, 76 insertions, 0 deletions

diff --git a/offload/test/api/omp_device_uid.c b/offload/test/api/omp_device_uid.c
new file mode 100644
index 000000000000..2a41d8d04ef8
--- /dev/null
+++ b/offload/test/api/omp_device_uid.c
@@ -0,0 +1,76 @@
+// RUN: %libomptarget-compile-run-and-check-generic
+
+#include <omp.h>
+#include <stdio.h>
+#include <string.h>
+
+int test_omp_device_uid(int device_num) {
+  const char *device_uid = omp_get_uid_from_device(device_num);
+  if (device_uid == NULL) {
+    printf("FAIL for device %d: omp_get_uid_from_device returned NULL\n",
+           device_num);
+    return 0;
+  }
+
+  int device_num_from_uid = omp_get_device_from_uid(device_uid);
+  if (device_num_from_uid != device_num) {
+    printf(
+        "FAIL for device %d: omp_get_device_from_uid returned %d (UID: %s)\n",
+        device_num, device_num_from_uid, device_uid);
+    return 0;
+  }
+
+  if (device_num == omp_get_initial_device())
+    return 1;
+
+  int success = 1;
+
+// Note that the following code may be executed on the host if the host is the
+// device
+#pragma omp target map(tofrom : success) device(device_num)
+  {
+    int device_num = omp_get_device_num();
+
+    // omp_get_uid_from_device() in the device runtime is a dummy function
+    // returning NULL
+    const char *device_uid = omp_get_uid_from_device(device_num);
+
+    // omp_get_device_from_uid() in the device runtime is a dummy function
+    // returning omp_invalid_device.
+    int device_num_from_uid = omp_get_device_from_uid(device_uid);
+
+    // Depending on whether we're executing on the device or the host, we either
+    // got NULL as the device UID or the correct device UID.  Consequently,
+    // omp_get_device_from_uid() either returned omp_invalid_device or the
+    // correct device number (aka omp_get_initial_device()).
+    if (device_uid ? device_num_from_uid != device_num
+                   : device_num_from_uid != omp_invalid_device) {
+      printf("FAIL for device %d (target): omp_get_device_from_uid returned %d "
+             "(UID: %s)\n",
+             device_num, device_num_from_uid, device_uid);
+      success = 0;
+    }
+  }
+
+  return success;
+}
+
+int main() {
+  int num_devices = omp_get_num_devices();
+  int num_failed = 0;
+  // (also test initial device aka num_devices)
+  for (int i = 0; i < num_devices + 1; i++) {
+    if (!test_omp_device_uid(i)) {
+      printf("FAIL for device %d\n", i);
+      num_failed++;
+    }
+  }
+  if (num_failed) {
+    printf("FAIL\n");
+    return 1;
+  }
+  printf("PASS\n");
+  return 0;
+}
+
+// CHECK: PASS