[OpenMP] Add omp_get_device_num() and update several other device API functions

Add omp_get_device_num() function for 5.0 which returns the number of the
device the current thread is running on. Currently, we are leaving it to the
compiler to handle this properly if it is called inside target.

Also, did some cleanup and updating of duplicate device API functions (in both
libomp and libomptarget) to make them into weak functions that check for the
symbol from libomptarget, and will call the version in libomptarget if it is
present. If any additional device API functions are implemented also in
libomptarget in the future, we should add the dlsym calls to the host functions.
Also, if the omp_target_* functions are to be implemented for the host (this has
been requested), they should attempt to call the libomptarget versions as well.

Patch by Terry Wilmarth

Differential Revision: https://reviews.llvm.org/D55578

13 files changed, 172 insertions, 48 deletions

diff --git a/openmp/libomptarget/test/api/omp_get_num_devices.c b/openmp/libomptarget/test/api/omp_get_num_devices.c
new file mode 100644
index 00000000000..d0e84db6b10
--- /dev/null
+++ b/openmp/libomptarget/test/api/omp_get_num_devices.c
@@ -0,0 +1,36 @@
+// RUN: %libomptarget-compile-run-and-check-aarch64-unknown-linux-gnu
+// RUN: %libomptarget-compile-run-and-check-powerpc64-ibm-linux-gnu
+// RUN: %libomptarget-compile-run-and-check-powerpc64le-ibm-linux-gnu
+// RUN: %libomptarget-compile-run-and-check-x86_64-pc-linux-gnu
+
+#include <stdio.h>
+#include <omp.h>
+
+int test_omp_get_num_devices()
+{
+  /* checks that omp_get_num_devices() > 0 */
+  int num_devices = omp_get_num_devices();
+  printf("num_devices = %d\n", num_devices);
+
+  #pragma omp target
+  {}
+
+  return (num_devices > 0);
+}
+
+int main()
+{
+  int i;
+  int failed=0;
+
+  if (!test_omp_get_num_devices()) {
+    failed++;
+  }
+  if (failed)
+    printf("FAIL\n");
+  else
+    printf("PASS\n");
+  return failed;
+}
+
+// CHECK: PASS
diff --git a/openmp/runtime/src/dllexports b/openmp/runtime/src/dllexports
index 963ac619ae7..9885f87bf48 100644
--- a/openmp/runtime/src/dllexports
+++ b/openmp/runtime/src/dllexports
@@ -510,9 +510,7 @@ kmp_set_warnings_off                        780
     omp_is_initial_device                   869
     omp_set_default_device                  879
     omp_get_default_device                  880
-    %ifdef stub
-        omp_get_num_devices                 881
-    %endif
+    omp_get_num_devices                     881
 %endif # OMP_40
 
 # OpenMP 45
@@ -527,8 +525,8 @@ kmp_set_warnings_off                        780
     omp_get_place_num                       876
     omp_get_partition_num_places            877
     omp_get_partition_place_nums            878
+    omp_get_initial_device                  882
     %ifdef stub
-        omp_get_initial_device              882
         omp_target_alloc                    883
         omp_target_free                     884
         omp_target_is_present               885
@@ -547,6 +545,7 @@ kmp_set_disp_num_buffers                    890
     omp_get_default_allocator               893
     omp_alloc                               894
     omp_free                                895
+    omp_get_device_num                      896
     omp_set_affinity_format                 748
     omp_get_affinity_format                 749
     omp_display_affinity                    750
diff --git a/openmp/runtime/src/include/45/omp.h.var b/openmp/runtime/src/include/45/omp.h.var
index e222fff9474..f30da51d813 100644
--- a/openmp/runtime/src/include/45/omp.h.var
+++ b/openmp/runtime/src/include/45/omp.h.var
@@ -195,4 +195,3 @@
 #   endif
 
 #endif /* __OMP_H */
-
diff --git a/openmp/runtime/src/include/45/omp_lib.f.var b/openmp/runtime/src/include/45/omp_lib.f.var
index 74e6bc3ecb5..44e7cc2cdce 100644
--- a/openmp/runtime/src/include/45/omp_lib.f.var
+++ b/openmp/runtime/src/include/45/omp_lib.f.var
@@ -562,6 +562,7 @@
 !dec$ attributes alias:'OMP_GET_TEAM_NUM' :: omp_get_team_num
 !dec$ attributes alias:'OMP_GET_CANCELLATION' :: omp_get_cancellation
 !dec$ attributes alias:'OMP_IS_INITIAL_DEVICE' :: omp_is_initial_device
+!dec$ attributes alias:'OMP_GET_INITIAL_DEVICE' :: omp_get_initial_device
 !dec$ attributes alias:'OMP_GET_MAX_TASK_PRIORITY' :: omp_get_max_task_priority
 
 !dec$ attributes alias:'omp_init_lock' :: omp_init_lock
@@ -642,6 +643,7 @@
 !dec$ attributes alias:'_OMP_GET_TEAM_NUM' :: omp_get_team_num
 !dec$ attributes alias:'_OMP_GET_CANCELLATION' :: omp_get_cancellation
 !dec$ attributes alias:'_OMP_IS_INITIAL_DEVICE' :: omp_is_initial_device
+!dec$ attributes alias:'_OMP_GET_INITIAL_DEVICE' :: omp_get_initial_device
 !dec$ attributes alias:'_OMP_GET_MAX_TASK_PRIORTY' :: omp_get_max_task_priority
 
 !dec$ attributes alias:'_omp_init_lock' :: omp_init_lock
@@ -725,6 +727,7 @@
 !dec$ attributes alias:'omp_get_team_num_'::omp_get_team_num
 !dec$ attributes alias:'omp_get_cancellation_'::omp_get_cancellation
 !dec$ attributes alias:'omp_is_initial_device_'::omp_is_initial_device
+!dec$ attributes alias:'omp_get_initial_device_'::omp_get_initial_device
 !dec$ attributes alias:'omp_get_max_task_priority_'::omp_get_max_task_priority
 
 !dec$ attributes alias:'omp_init_lock_'::omp_init_lock
@@ -800,10 +803,14 @@
 !dec$ attributes alias:'_omp_get_proc_bind_' :: omp_get_proc_bind
 !dec$ attributes alias:'_omp_get_wtime_'::omp_get_wtime
 !dec$ attributes alias:'_omp_get_wtick_'::omp_get_wtick
+!dec$ attributes alias:'_omp_get_default_device_'::omp_get_default_device
+!dec$ attributes alias:'_omp_set_default_device_'::omp_set_default_device
+!dec$ attributes alias:'_omp_get_num_devices_'::omp_get_num_devices
 !dec$ attributes alias:'_omp_get_num_teams_'::omp_get_num_teams
 !dec$ attributes alias:'_omp_get_team_num_'::omp_get_team_num
 !dec$ attributes alias:'_omp_get_cancellation_'::omp_get_cancellation
 !dec$ attributes alias:'_omp_is_initial_device_'::omp_is_initial_device
+!dec$ attributes alias:'_omp_get_initial_device_'::omp_get_initial_device
 !dec$ attributes alias:'_omp_get_max_task_priorty_'::omp_get_max_task_priority
 
 !dec$ attributes alias:'_omp_init_lock_'::omp_init_lock
@@ -852,4 +859,3 @@
 !dec$ endif
 
       end module omp_lib
-
diff --git a/openmp/runtime/src/include/45/omp_lib.h.var b/openmp/runtime/src/include/45/omp_lib.h.var
index 58763b35e06..1ed00cd02de 100644
--- a/openmp/runtime/src/include/45/omp_lib.h.var
+++ b/openmp/runtime/src/include/45/omp_lib.h.var
@@ -523,6 +523,7 @@
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_default_device
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_set_default_device
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_is_initial_device
+!DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_initial_device
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_num_devices
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_num_teams
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_team_num
@@ -595,6 +596,7 @@
 !$omp declare target(omp_get_default_device )
 !$omp declare target(omp_set_default_device )
 !$omp declare target(omp_is_initial_device )
+!$omp declare target(omp_get_initial_device )
 !$omp declare target(omp_get_num_devices )
 !$omp declare target(omp_get_num_teams )
 !$omp declare target(omp_get_team_num )
@@ -641,4 +643,3 @@
 !$omp declare target(omp_init_nest_lock_with_hint )
 !DIR$ ENDIF
 !DIR$ ENDIF
-
diff --git a/openmp/runtime/src/include/50/omp.h.var b/openmp/runtime/src/include/50/omp.h.var
index 81b6c854246..872b8f5007d 100644
--- a/openmp/runtime/src/include/50/omp.h.var
+++ b/openmp/runtime/src/include/50/omp.h.var
@@ -146,6 +146,9 @@
     extern int   __KAI_KMPC_CONVENTION  omp_target_associate_ptr(void *, void *, size_t, size_t, int);
     extern int   __KAI_KMPC_CONVENTION  omp_target_disassociate_ptr(void *, int);
 
+    /* OpenMP 5.0 */
+    extern int   __KAI_KMPC_CONVENTION  omp_get_device_num (void);
+
     /* kmp API functions */
     extern int    __KAI_KMPC_CONVENTION  kmp_get_stacksize          (void);
     extern void   __KAI_KMPC_CONVENTION  kmp_set_stacksize          (int);
@@ -260,4 +263,3 @@
 #   endif
 
 #endif /* __OMP_H */
-
diff --git a/openmp/runtime/src/include/50/omp_lib.f.var b/openmp/runtime/src/include/50/omp_lib.f.var
index d5a80573429..bebb6e9de94 100644
--- a/openmp/runtime/src/include/50/omp_lib.f.var
+++ b/openmp/runtime/src/include/50/omp_lib.f.var
@@ -278,6 +278,11 @@
             integer (kind=omp_integer_kind) omp_get_initial_device
           end function omp_get_initial_device
 
+          function omp_get_device_num()
+            use omp_lib_kinds
+            integer (kind=omp_integer_kind) omp_get_device_num
+          end function omp_get_device_num
+
           subroutine omp_init_lock(svar)
 !DIR$ IF(__INTEL_COMPILER.GE.1400)
 !DIR$ attributes known_intrinsic :: omp_init_lock
@@ -613,7 +618,9 @@
 !dec$ attributes alias:'OMP_GET_TEAM_NUM' :: omp_get_team_num
 !dec$ attributes alias:'OMP_GET_CANCELLATION' :: omp_get_cancellation
 !dec$ attributes alias:'OMP_IS_INITIAL_DEVICE' :: omp_is_initial_device
+!dec$ attributes alias:'OMP_GET_INITIAL_DEVICE' :: omp_get_initial_device
 !dec$ attributes alias:'OMP_GET_MAX_TASK_PRIORITY' :: omp_get_max_task_priority
+!dec$ attributes alias:'OMP_GET_DEVICE_NUM' :: omp_get_device_num
 !dec$ attributes alias:'OMP_CONTROL_TOOL' :: omp_control_tool
 !dec$ attributes alias:'OMP_SET_AFFINITY_FORMAT' :: omp_set_affinity_format
 !dec$ attributes alias:'OMP_GET_AFFINITY_FORMAT' :: omp_get_affinity_format
@@ -698,7 +705,9 @@
 !dec$ attributes alias:'_OMP_GET_TEAM_NUM' :: omp_get_team_num
 !dec$ attributes alias:'_OMP_GET_CANCELLATION' :: omp_get_cancellation
 !dec$ attributes alias:'_OMP_IS_INITIAL_DEVICE' :: omp_is_initial_device
+!dec$ attributes alias:'_OMP_GET_INITIAL_DEVICE' :: omp_get_initial_device
 !dec$ attributes alias:'_OMP_GET_MAX_TASK_PRIORTY' :: omp_get_max_task_priority
+!dec$ attributes alias:'_OMP_GET_DEVICE_NUM' :: omp_get_device_num
 !dec$ attributes alias:'_OMP_CONTROL_TOOL' :: omp_control_tool
 !dec$ attributes alias:'_OMP_SET_AFFINITY_FORMAT' :: omp_set_affinity_format
 !dec$ attributes alias:'_OMP_GET_AFFINITY_FORMAT' :: omp_get_affinity_format
@@ -786,7 +795,9 @@
 !dec$ attributes alias:'omp_get_team_num_'::omp_get_team_num
 !dec$ attributes alias:'omp_get_cancellation_'::omp_get_cancellation
 !dec$ attributes alias:'omp_is_initial_device_'::omp_is_initial_device
+!dec$ attributes alias:'omp_get_initial_device_'::omp_get_initial_device
 !dec$ attributes alias:'omp_get_max_task_priority_'::omp_get_max_task_priority
+!dec$ attributes alias:'omp_get_device_num_'::omp_get_device_num
 !dec$ attributes alias:'omp_set_affinity_format_' :: omp_set_affinity_format
 !dec$ attributes alias:'omp_get_affinity_format_' :: omp_get_affinity_format
 !dec$ attributes alias:'omp_display_affinity_' :: omp_display_affinity
@@ -866,12 +877,16 @@
 !dec$ attributes alias:'_omp_get_proc_bind_' :: omp_get_proc_bind
 !dec$ attributes alias:'_omp_get_wtime_'::omp_get_wtime
 !dec$ attributes alias:'_omp_get_wtick_'::omp_get_wtick
+!dec$ attributes alias:'_omp_get_default_device_'::omp_get_default_device
+!dec$ attributes alias:'_omp_set_default_device_'::omp_set_default_device
+!dec$ attributes alias:'_omp_get_num_devices_'::omp_get_num_devices
 !dec$ attributes alias:'_omp_get_num_teams_'::omp_get_num_teams
 !dec$ attributes alias:'_omp_get_team_num_'::omp_get_team_num
 !dec$ attributes alias:'_omp_get_cancellation_'::omp_get_cancellation
 !dec$ attributes alias:'_omp_is_initial_device_'::omp_is_initial_device
+!dec$ attributes alias:'_omp_get_initial_device_'::omp_get_initial_device
 !dec$ attributes alias:'_omp_get_max_task_priorty_'::omp_get_max_task_priority
-
+!dec$ attributes alias:'_omp_get_device_num_'::omp_get_device_num
 !dec$ attributes alias:'_omp_init_lock_'::omp_init_lock
 !dec$ attributes alias:'_omp_init_lock_with_hint_'::omp_init_lock_with_hint
 !dec$ attributes alias:'_omp_destroy_lock_'::omp_destroy_lock
@@ -923,4 +938,3 @@
 !dec$ endif
 
       end module omp_lib
-
diff --git a/openmp/runtime/src/include/50/omp_lib.f90.var b/openmp/runtime/src/include/50/omp_lib.f90.var
index afc6d6739f4..e0233de81d7 100644
--- a/openmp/runtime/src/include/50/omp_lib.f90.var
+++ b/openmp/runtime/src/include/50/omp_lib.f90.var
@@ -294,6 +294,11 @@
             integer (kind=omp_integer_kind) omp_get_initial_device
           end function omp_get_initial_device
 
+          function omp_get_device_num() bind(c)
+            use omp_lib_kinds
+            integer (kind=omp_integer_kind) omp_get_device_num
+          end function omp_get_device_num
+
           subroutine omp_init_lock(svar) bind(c)
 !DIR$ IF(__INTEL_COMPILER.GE.1400)
 !DIR$ attributes known_intrinsic :: omp_init_lock
diff --git a/openmp/runtime/src/include/50/omp_lib.h.var b/openmp/runtime/src/include/50/omp_lib.h.var
index 11dbc0a5911..605b410dd82 100644
--- a/openmp/runtime/src/include/50/omp_lib.h.var
+++ b/openmp/runtime/src/include/50/omp_lib.h.var
@@ -327,6 +327,11 @@
           integer (kind=omp_integer_kind) omp_get_initial_device
         end function omp_get_initial_device
 
+        function omp_get_device_num() bind(c)
+          import
+          integer (kind=omp_integer_kind) omp_get_device_num
+        end function omp_get_device_num
+
         subroutine omp_init_lock(svar) bind(c)
 !DIR$ IF(__INTEL_COMPILER.GE.1400)
 !DIR$ attributes known_intrinsic :: omp_init_lock
@@ -644,7 +649,9 @@
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_default_device
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_set_default_device
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_is_initial_device
+!DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_initial_device
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_num_devices
+!DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_device_num
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_num_teams
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_get_team_num
 !DIR$ ATTRIBUTES OFFLOAD:MIC :: omp_init_lock
@@ -721,7 +728,9 @@
 !$omp declare target(omp_get_default_device )
 !$omp declare target(omp_set_default_device )
 !$omp declare target(omp_is_initial_device )
+!$omp declare target(omp_get_initial_device )
 !$omp declare target(omp_get_num_devices )
+!$omp declare target(omp_get_device_num )
 !$omp declare target(omp_get_num_teams )
 !$omp declare target(omp_get_team_num )
 !$omp declare target(omp_init_lock )
diff --git a/openmp/runtime/src/kmp.h b/openmp/runtime/src/kmp.h
index 23bbeb35ca9..a1b9b7eaa57 100644
--- a/openmp/runtime/src/kmp.h
+++ b/openmp/runtime/src/kmp.h
@@ -4000,6 +4000,13 @@ extern kmp_target_offload_kind_t __kmp_target_offload;
 extern int __kmpc_get_target_offload();
 #endif
 
+#if OMP_40_ENABLED
+// Constants used in libomptarget
+#define KMP_DEVICE_DEFAULT -1 // This is libomptarget's default device.
+#define KMP_HOST_DEVICE -10 // This is what it is in libomptarget, go figure.
+#define KMP_DEVICE_ALL -11 // This is libomptarget's "all devices".
+#endif // OMP_40_ENABLED
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/openmp/runtime/src/kmp_ftn_entry.h b/openmp/runtime/src/kmp_ftn_entry.h
index abf1892d970..c14f73cb4ae 100644
--- a/openmp/runtime/src/kmp_ftn_entry.h
+++ b/openmp/runtime/src/kmp_ftn_entry.h
@@ -944,39 +944,53 @@ void FTN_STDCALL KMP_EXPAND_NAME(FTN_SET_DEFAULT_DEVICE)(int KMP_DEREF arg) {
 #endif
 }
 
-#if KMP_MIC || KMP_OS_DARWIN || defined(KMP_STUB)
-
-int FTN_STDCALL FTN_GET_NUM_DEVICES(void) { return 0; }
-
-#endif // KMP_MIC || KMP_OS_DARWIN || defined(KMP_STUB)
-
-#if !KMP_OS_LINUX
-
-int FTN_STDCALL KMP_EXPAND_NAME(FTN_IS_INITIAL_DEVICE)(void) { return 1; }
-
+// Get number of NON-HOST devices.
+// libomptarget, if loaded, provides this function in api.cpp.
+int FTN_STDCALL KMP_EXPAND_NAME(FTN_GET_NUM_DEVICES)(void) KMP_WEAK_ATTRIBUTE;
+int FTN_STDCALL KMP_EXPAND_NAME(FTN_GET_NUM_DEVICES)(void) {
+#if KMP_MIC || KMP_OS_DARWIN || KMP_OS_WINDOWS || defined(KMP_STUB)
+  return 0;
 #else
-
-// This internal function is used when the entry from the offload library
-// is not found.
-int _Offload_get_device_number(void) KMP_WEAK_ATTRIBUTE;
-
-int FTN_STDCALL KMP_EXPAND_NAME(FTN_IS_INITIAL_DEVICE)(void) {
-  if (_Offload_get_device_number) {
-    return _Offload_get_device_number() == -1;
-  } else {
-    return 1;
+  int (*fptr)();
+  if ((*(void **)(&fptr) = dlsym(RTLD_DEFAULT, "_Offload_number_of_devices"))) {
+    return (*fptr)();
+  } else if ((*(void **)(&fptr) = dlsym(RTLD_NEXT, "omp_get_num_devices"))) {
+    return (*fptr)();
+  } else { // liboffload & libomptarget don't exist
+    return 0;
   }
+#endif // KMP_MIC || KMP_OS_DARWIN || KMP_OS_WINDOWS || defined(KMP_STUB)
 }
 
-#endif // ! KMP_OS_LINUX
+// This function always returns true when called on host device.
+// Compilier/libomptarget should handle when it is called inside target region.
+int FTN_STDCALL KMP_EXPAND_NAME(FTN_IS_INITIAL_DEVICE)(void) KMP_WEAK_ATTRIBUTE;
+int FTN_STDCALL KMP_EXPAND_NAME(FTN_IS_INITIAL_DEVICE)(void) {
+  return 1; // This is the host
+}
 
 #endif // OMP_40_ENABLED
 
-#if OMP_45_ENABLED && defined(KMP_STUB)
-// OpenMP 4.5 entries for stubs library
-
-int FTN_STDCALL FTN_GET_INITIAL_DEVICE(void) { return -1; }
+#if OMP_45_ENABLED
+// OpenMP 4.5 entries
+
+// libomptarget, if loaded, provides this function
+int FTN_STDCALL FTN_GET_INITIAL_DEVICE(void) KMP_WEAK_ATTRIBUTE;
+int FTN_STDCALL FTN_GET_INITIAL_DEVICE(void) {
+#if KMP_MIC || KMP_OS_DARWIN || KMP_OS_WINDOWS || defined(KMP_STUB)
+  return KMP_HOST_DEVICE;
+#else
+  int (*fptr)();
+  if ((*(void **)(&fptr) = dlsym(RTLD_NEXT, "omp_get_initial_device"))) {
+    return (*fptr)();
+  } else { // liboffload & libomptarget don't exist
+    return KMP_HOST_DEVICE;
+  }
+#endif
+}
 
+#if defined(KMP_STUB)
+// Entries for stubs library
 // As all *target* functions are C-only parameters always passed by value
 void *FTN_STDCALL FTN_TARGET_ALLOC(size_t size, int device_num) { return 0; }
 
@@ -1007,7 +1021,8 @@ int FTN_STDCALL FTN_TARGET_ASSOCIATE_PTR(void *host_ptr, void *device_ptr,
 int FTN_STDCALL FTN_TARGET_DISASSOCIATE_PTR(void *host_ptr, int device_num) {
   return -1;
 }
-#endif // OMP_45_ENABLED && defined(KMP_STUB)
+#endif // defined(KMP_STUB)
+#endif // OMP_45_ENABLED
 
 #ifdef KMP_STUB
 typedef enum { UNINIT = -1, UNLOCKED, LOCKED } kmp_stub_lock_t;
@@ -1318,6 +1333,14 @@ int FTN_STDCALL KMP_EXPAND_NAME(FTN_GET_MAX_TASK_PRIORITY)(void) {
 }
 #endif
 
+#if OMP_50_ENABLED
+// This function will be defined in libomptarget. When libomptarget is not
+// loaded, we assume we are on the host and return KMP_HOST_DEVICE.
+// Compiler/libomptarget will handle this if called inside target.
+int FTN_STDCALL FTN_GET_DEVICE_NUM(void) KMP_WEAK_ATTRIBUTE;
+int FTN_STDCALL FTN_GET_DEVICE_NUM(void) { return KMP_HOST_DEVICE; }
+#endif // OMP_50_ENABLED
+
 // GCC compatibility (versioned symbols)
 #ifdef KMP_USE_VERSION_SYMBOLS
 
@@ -1401,6 +1424,7 @@ KMP_VERSION_SYMBOL(FTN_GET_CANCELLATION, 40, "OMP_4.0");
 KMP_VERSION_SYMBOL(FTN_GET_DEFAULT_DEVICE, 40, "OMP_4.0");
 KMP_VERSION_SYMBOL(FTN_SET_DEFAULT_DEVICE, 40, "OMP_4.0");
 KMP_VERSION_SYMBOL(FTN_IS_INITIAL_DEVICE, 40, "OMP_4.0");
+KMP_VERSION_SYMBOL(FTN_GET_NUM_DEVICES, 40, "OMP_4.0");
 #endif /* OMP_40_ENABLED */
 
 #if OMP_45_ENABLED
@@ -1412,10 +1436,12 @@ KMP_VERSION_SYMBOL(FTN_GET_PLACE_PROC_IDS, 45, "OMP_4.5");
 KMP_VERSION_SYMBOL(FTN_GET_PLACE_NUM, 45, "OMP_4.5");
 KMP_VERSION_SYMBOL(FTN_GET_PARTITION_NUM_PLACES, 45, "OMP_4.5");
 KMP_VERSION_SYMBOL(FTN_GET_PARTITION_PLACE_NUMS, 45, "OMP_4.5");
+// KMP_VERSION_SYMBOL(FTN_GET_INITIAL_DEVICE, 45, "OMP_4.5");
 #endif
 
 #if OMP_50_ENABLED
 // OMP_5.0 versioned symbols
+// KMP_VERSION_SYMBOL(FTN_GET_DEVICE_NUM, 50, "OMP_5.0");
 #endif
 
 #endif // KMP_USE_VERSION_SYMBOLS
diff --git a/openmp/runtime/src/kmp_ftn_os.h b/openmp/runtime/src/kmp_ftn_os.h
index 47188fcc4d6..776db392a68 100644
--- a/openmp/runtime/src/kmp_ftn_os.h
+++ b/openmp/runtime/src/kmp_ftn_os.h
@@ -100,9 +100,7 @@
 #define FTN_GET_WTICK omp_get_wtick
 
 #if OMP_40_ENABLED
-#if KMP_MIC || KMP_OS_DARWIN || defined(KMP_STUB)
 #define FTN_GET_NUM_DEVICES omp_get_num_devices
-#endif
 #define FTN_GET_DEFAULT_DEVICE omp_get_default_device
 #define FTN_SET_DEFAULT_DEVICE omp_set_default_device
 #define FTN_IS_INITIAL_DEVICE omp_is_initial_device
@@ -121,8 +119,8 @@
 #define FTN_GET_PLACE_NUM omp_get_place_num
 #define FTN_GET_PARTITION_NUM_PLACES omp_get_partition_num_places
 #define FTN_GET_PARTITION_PLACE_NUMS omp_get_partition_place_nums
-#ifdef KMP_STUB
 #define FTN_GET_INITIAL_DEVICE omp_get_initial_device
+#ifdef KMP_STUB
 #define FTN_TARGET_ALLOC omp_target_alloc
 #define FTN_TARGET_FREE omp_target_free
 #define FTN_TARGET_IS_PRESENT omp_target_is_present
@@ -139,6 +137,7 @@
 #define FTN_GET_DEFAULT_ALLOCATOR omp_get_default_allocator
 #define FTN_ALLOC omp_alloc
 #define FTN_FREE omp_free
+#define FTN_GET_DEVICE_NUM omp_get_device_num
 #define FTN_SET_AFFINITY_FORMAT omp_set_affinity_format
 #define FTN_GET_AFFINITY_FORMAT omp_get_affinity_format
 #define FTN_DISPLAY_AFFINITY omp_display_affinity
@@ -230,9 +229,7 @@
 #define FTN_GET_WTICK omp_get_wtick_
 
 #if OMP_40_ENABLED
-#if KMP_MIC || KMP_OS_DARWIN || defined(KMP_STUB)
 #define FTN_GET_NUM_DEVICES omp_get_num_devices_
-#endif
 #define FTN_GET_DEFAULT_DEVICE omp_get_default_device_
 #define FTN_SET_DEFAULT_DEVICE omp_set_default_device_
 #define FTN_IS_INITIAL_DEVICE omp_is_initial_device_
@@ -251,8 +248,8 @@
 #define FTN_GET_PLACE_NUM omp_get_place_num_
 #define FTN_GET_PARTITION_NUM_PLACES omp_get_partition_num_places_
 #define FTN_GET_PARTITION_PLACE_NUMS omp_get_partition_place_nums_
-#ifdef KMP_STUB
 #define FTN_GET_INITIAL_DEVICE omp_get_initial_device_
+#ifdef KMP_STUB
 #define FTN_TARGET_ALLOC omp_target_alloc_
 #define FTN_TARGET_FREE omp_target_free_
 #define FTN_TARGET_IS_PRESENT omp_target_is_present_
@@ -269,6 +266,7 @@
 #define FTN_GET_DEFAULT_ALLOCATOR omp_get_default_allocator_
 #define FTN_ALLOC omp_alloc_
 #define FTN_FREE omp_free_
+#define FTN_GET_DEVICE_NUM omp_get_device_num_
 #define FTN_SET_AFFINITY_FORMAT omp_set_affinity_format_
 #define FTN_GET_AFFINITY_FORMAT omp_get_affinity_format_
 #define FTN_DISPLAY_AFFINITY omp_display_affinity_
@@ -360,9 +358,7 @@
 #define FTN_GET_WTICK OMP_GET_WTICK
 
 #if OMP_40_ENABLED
-#if KMP_MIC || KMP_OS_DARWIN || defined(KMP_STUB)
 #define FTN_GET_NUM_DEVICES OMP_GET_NUM_DEVICES
-#endif
 #define FTN_GET_DEFAULT_DEVICE OMP_GET_DEFAULT_DEVICE
 #define FTN_SET_DEFAULT_DEVICE OMP_SET_DEFAULT_DEVICE
 #define FTN_IS_INITIAL_DEVICE OMP_IS_INITIAL_DEVICE
@@ -381,8 +377,8 @@
 #define FTN_GET_PLACE_NUM OMP_GET_PLACE_NUM
 #define FTN_GET_PARTITION_NUM_PLACES OMP_GET_PARTITION_NUM_PLACES
 #define FTN_GET_PARTITION_PLACE_NUMS OMP_GET_PARTITION_PLACE_NUMS
-#ifdef KMP_STUB
 #define FTN_GET_INITIAL_DEVICE OMP_GET_INITIAL_DEVICE
+#ifdef KMP_STUB
 #define FTN_TARGET_ALLOC OMP_TARGET_ALLOC
 #define FTN_TARGET_FREE OMP_TARGET_FREE
 #define FTN_TARGET_IS_PRESENT OMP_TARGET_IS_PRESENT
@@ -399,6 +395,7 @@
 #define FTN_GET_DEFAULT_ALLOCATOR OMP_GET_DEFAULT_ALLOCATOR
 #define FTN_ALLOC OMP_ALLOC
 #define FTN_FREE OMP_FREE
+#define FTN_GET_DEVICE_NUM OMP_GET_DEVICE_NUM
 #define FTN_SET_AFFINITY_FORMAT OMP_SET_AFFINITY_FORMAT
 #define FTN_GET_AFFINITY_FORMAT OMP_GET_AFFINITY_FORMAT
 #define FTN_DISPLAY_AFFINITY OMP_DISPLAY_AFFINITY
@@ -490,9 +487,7 @@
 #define FTN_GET_WTICK OMP_GET_WTICK_
 
 #if OMP_40_ENABLED
-#if KMP_MIC || KMP_OS_DARWIN || defined(KMP_STUB)
 #define FTN_GET_NUM_DEVICES OMP_GET_NUM_DEVICES_
-#endif
 #define FTN_GET_DEFAULT_DEVICE OMP_GET_DEFAULT_DEVICE_
 #define FTN_SET_DEFAULT_DEVICE OMP_SET_DEFAULT_DEVICE_
 #define FTN_IS_INITIAL_DEVICE OMP_IS_INITIAL_DEVICE_
@@ -511,8 +506,8 @@
 #define FTN_GET_PLACE_NUM OMP_GET_PLACE_NUM_
 #define FTN_GET_PARTITION_NUM_PLACES OMP_GET_PARTITION_NUM_PLACES_
 #define FTN_GET_PARTITION_PLACE_NUMS OMP_GET_PARTITION_PLACE_NUMS_
-#ifdef KMP_STUB
 #define FTN_GET_INITIAL_DEVICE OMP_GET_INITIAL_DEVICE_
+#ifdef KMP_STUB
 #define FTN_TARGET_ALLOC OMP_TARGET_ALLOC_
 #define FTN_TARGET_FREE OMP_TARGET_FREE_
 #define FTN_TARGET_IS_PRESENT OMP_TARGET_IS_PRESENT_
@@ -529,6 +524,7 @@
 #define FTN_GET_DEFAULT_ALLOCATOR OMP_GET_DEFAULT_ALLOCATOR_
 #define FTN_ALLOC OMP_ALLOC_
 #define FTN_FREE OMP_FREE_
+#define FTN_GET_DEVICE_NUM OMP_GET_DEVICE_NUM_
 #define FTN_SET_AFFINITY_FORMAT OMP_SET_AFFINITY_FORMAT_
 #define FTN_GET_AFFINITY_FORMAT OMP_GET_AFFINITY_FORMAT_
 #define FTN_DISPLAY_AFFINITY OMP_DISPLAY_AFFINITY_
diff --git a/openmp/runtime/test/api/omp_get_num_devices.c b/openmp/runtime/test/api/omp_get_num_devices.c
new file mode 100644
index 00000000000..d534fa3d726
--- /dev/null
+++ b/openmp/runtime/test/api/omp_get_num_devices.c
@@ -0,0 +1,24 @@
+// RUN: %libomp-compile-and-run
+#include <stdio.h>
+#include "omp_testsuite.h"
+
+int test_omp_get_num_devices()
+{
+  /* checks that omp_get_device_num */
+  int num_devices = omp_get_num_devices();
+
+  return (num_devices == 0);
+}
+
+int main()
+{
+  int i;
+  int num_failed=0;
+
+  for(i = 0; i < REPETITIONS; i++) {
+    if(!test_omp_get_num_devices()) {
+      num_failed++;
+    }
+  }
+  return num_failed;
+}