[OpenMP] Add GOMP 5.0 version symbols to API

[jlpeyton]

Summary

• Add GOMP versioned pause functions
• Add GOMP versioned affinity format functions

To do the affinity format functions, only attach versioned symbols
to the APPEND Fortran entries (e.g., omp_set_affinity_format_) since
GOMP only exports two symbols (one for Fortran, one for C). Our
affinity format functions have three symbols.
e.g., with omp_set_affinity_format:

1. omp_set_affinity_format (Fortran interface)
2. omp_set_affinity_format_ (Fortran interface)
3. ompc_set_affinity_format (C interface)

Have the GOMP version of the C symbol alias the ompc_* 3) version instead of the Fortran unappended version 1).

[AndreyChurbanov]

LGTM. One nit: probably clang-format suggestions can be applied.

[tianshilei1992]

We have seen a couple of reports bout the new APIs introduced in this patch, such as https://github.com/llvm/llvm-project/issues/60393 and https://github.com/llvm/llvm-project/issues/58472. Can you please fix it? We have the issue in both LLVM 15 and 16 now.

openmp/runtime/src/exports_so.txt

 OMP_3.0 {
 } OMP_2.0;
 OMP_3.1 {
 } OMP_3.0;
 OMP_4.0 {
 } OMP_3.1;
 OMP_4.5 {
 } OMP_4.0;
+OMP_5.0 {
+} OMP_4.5;
 
 # sets up GCC GOMP_ version dependency chain
 GOMP_1.0 {
 };
 GOMP_2.0 {
 } GOMP_1.0;
 GOMP_3.0 {
 } GOMP_2.0;
 GOMP_4.0 {
 } GOMP_3.0;
 GOMP_4.5 {
 } GOMP_4.0;
 GOMP_5.0 {
 } GOMP_4.5;
 
 # end of file #

openmp/runtime/src/kmp.h

 KMP_EXPORT int KMPC_CONVENTION
 kmpc_get_affinity_mask_proc(int, kmp_affinity_mask_t *);
 
 KMP_EXPORT void KMPC_CONVENTION kmpc_set_stacksize(int);
 KMP_EXPORT void KMPC_CONVENTION kmpc_set_stacksize_s(size_t);
 KMP_EXPORT void KMPC_CONVENTION kmpc_set_library(int);
 KMP_EXPORT void KMPC_CONVENTION kmpc_set_defaults(char const *);
 KMP_EXPORT void KMPC_CONVENTION kmpc_set_disp_num_buffers(int);
+void KMP_EXPAND_NAME(ompc_set_affinity_format)(char const *format);
+size_t KMP_EXPAND_NAME(ompc_get_affinity_format)(char *buffer, size_t size);
+void KMP_EXPAND_NAME(ompc_display_affinity)(char const *format);
+size_t KMP_EXPAND_NAME(ompc_capture_affinity)(char *buffer, size_t buf_size,
+                                              char const *format);
 
 enum kmp_target_offload_kind {
   tgt_disabled = 0,
   tgt_default = 1,
   tgt_mandatory = 2
 };
 typedef enum kmp_target_offload_kind kmp_target_offload_kind_t;
 // Set via OMP_TARGET_OFFLOAD if specified, defaults to tgt_default otherwise

openmp/runtime/src/kmp_csupport.cpp

int ompc_get_ancestor_thread_num(int level) {
   return __kmp_get_ancestor_thread_num(__kmp_entry_gtid(), level);
 }
 
 int ompc_get_team_size(int level) {
   return __kmp_get_team_size(__kmp_entry_gtid(), level);
 }
 
 /* OpenMP 5.0 Affinity Format API */
-
-void ompc_set_affinity_format(char const *format) {
+void KMP_EXPAND_NAME(ompc_set_affinity_format)(char const *format) {
   if (!__kmp_init_serial) {
     __kmp_serial_initialize();
   }
   __kmp_strncpy_truncate(__kmp_affinity_format, KMP_AFFINITY_FORMAT_SIZE,
                          format, KMP_STRLEN(format) + 1);
 }
 
-size_t ompc_get_affinity_format(char *buffer, size_t size) {
+size_t KMP_EXPAND_NAME(ompc_get_affinity_format)(char *buffer, size_t size) {
   size_t format_size;
   if (!__kmp_init_serial) {
     __kmp_serial_initialize();
   }
   format_size = KMP_STRLEN(__kmp_affinity_format);
   if (buffer && size) {
     __kmp_strncpy_truncate(buffer, size, __kmp_affinity_format,
                            format_size + 1);
   }
   return format_size;
 }
 
-void ompc_display_affinity(char const *format) {
+void KMP_EXPAND_NAME(ompc_display_affinity)(char const *format) {
   int gtid;
   if (!TCR_4(__kmp_init_middle)) {
     __kmp_middle_initialize();
   }
   gtid = __kmp_get_gtid();
   __kmp_aux_display_affinity(gtid, format);
 }
 
-size_t ompc_capture_affinity(char *buffer, size_t buf_size,
+size_t KMP_EXPAND_NAME(ompc_capture_affinity)(char *buffer, size_t buf_size,
                                               char const *format) {
   int gtid;
   size_t num_required;
   kmp_str_buf_t capture_buf;
   if (!TCR_4(__kmp_init_middle)) {
     __kmp_middle_initialize();
   }
   gtid = __kmp_get_gtid();
   __kmp_str_buf_init(&capture_buf);
#endif // OMPT_SUPPORT
 
   if (severity == severity_warning)
     KMP_WARNING(UserDirectedWarning, src_loc, message);
   else
     KMP_FATAL(UserDirectedError, src_loc, message);
 
   __kmp_str_free(&src_loc);
 }
+
+#ifdef KMP_USE_VERSION_SYMBOLS
+// For GOMP compatibility there are two versions of each omp_* API.
+// One is the plain C symbol and one is the Fortran symbol with an appended
+// underscore. When we implement a specific ompc_* version of an omp_*
+// function, we want the plain GOMP versioned symbol to alias the ompc_* version
+// instead of the Fortran versions in kmp_ftn_entry.h
+extern "C" {
+// Have to undef these from omp.h so they aren't translated into
+// their ompc counterparts in the KMP_VERSION_OMPC_SYMBOL macros below
+#ifdef omp_set_affinity_format
+#undef omp_set_affinity_format
+#endif
+#ifdef omp_get_affinity_format
+#undef omp_get_affinity_format
+#endif
+#ifdef omp_display_affinity
+#undef omp_display_affinity
+#endif
+#ifdef omp_capture_affinity
+#undef omp_capture_affinity
+#endif
+KMP_VERSION_OMPC_SYMBOL(ompc_set_affinity_format, omp_set_affinity_format, 50,
+                        "OMP_5.0");
+KMP_VERSION_OMPC_SYMBOL(ompc_get_affinity_format, omp_get_affinity_format, 50,
+                        "OMP_5.0");
+KMP_VERSION_OMPC_SYMBOL(ompc_display_affinity, omp_display_affinity, 50,
+                        "OMP_5.0");
+KMP_VERSION_OMPC_SYMBOL(ompc_capture_affinity, omp_capture_affinity, 50,
+                        "OMP_5.0");
+} // extern "C"
+#endif

openmp/runtime/src/kmp_ftn_entry.h

 /*
  * kmp_ftn_entry.h -- Fortran entry linkage support for OpenMP.
  */
 
 //===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef FTN_STDCALL
 #error The support file kmp_ftn_entry.h should not be compiled by itself.
 #endif
 
 #ifdef KMP_STUB
 #include "kmp_stub.h"
 #endif
 
 #include "kmp_i18n.h"
 

 
 // This macro helps to reduce code duplication.
 #ifdef PASS_ARGS_BY_VALUE
 #define KMP_DEREF
 #else
 #define KMP_DEREF *
 #endif
 
+// For API with specific C vs. Fortran interfaces (ompc_* exists in
+// kmp_csupport.cpp), only create GOMP versioned symbols of the API for the
+// APPEND Fortran entries in this file. The GOMP versioned symbols of the C API
+// will take place where the ompc_* functions are defined.
+#if KMP_FTN_ENTRIES == KMP_FTN_APPEND
+#define KMP_EXPAND_NAME_IF_APPEND(name) KMP_EXPAND_NAME(name)
+#else
+#define KMP_EXPAND_NAME_IF_APPEND(name) name
+#endif
+
 void FTN_STDCALL FTN_SET_STACKSIZE(int KMP_DEREF arg) {
 #ifdef KMP_STUB
   __kmps_set_stacksize(KMP_DEREF arg);
 #else
   // __kmp_aux_set_stacksize initializes the library if needed
   __kmp_aux_set_stacksize((size_t)KMP_DEREF arg);
 #endif
 }
 
public:
   const char *get() const { return buf; }
 };
 #endif // KMP_STUB
 
 /*
  * Set the value of the affinity-format-var ICV on the current device to the
  * format specified in the argument.
  */
-void FTN_STDCALL FTN_SET_AFFINITY_FORMAT(char const *format, size_t size) {
+void FTN_STDCALL KMP_EXPAND_NAME_IF_APPEND(FTN_SET_AFFINITY_FORMAT)(
+    char const *format, size_t size) {
 #ifdef KMP_STUB
   return;
 #else
   if (!__kmp_init_serial) {
     __kmp_serial_initialize();
   }
   ConvertedString cformat(format, size);
   // Since the __kmp_affinity_format variable is a C string, do not
   // use the fortran strncpy function
   __kmp_strncpy_truncate(__kmp_affinity_format, KMP_AFFINITY_FORMAT_SIZE,
                          cformat.get(), KMP_STRLEN(cformat.get()));
 #endif
 }
 
 /*
  * Returns the number of characters required to hold the entire affinity format
  * specification (not including null byte character) and writes the value of the
  * affinity-format-var ICV on the current device to buffer. If the return value
  * is larger than size, the affinity format specification is truncated.
  */
-size_t FTN_STDCALL FTN_GET_AFFINITY_FORMAT(char *buffer, size_t size) {
+size_t FTN_STDCALL KMP_EXPAND_NAME_IF_APPEND(FTN_GET_AFFINITY_FORMAT)(
+    char *buffer, size_t size) {
 #ifdef KMP_STUB
   return 0;
 #else
   size_t format_size;
   if (!__kmp_init_serial) {
     __kmp_serial_initialize();
   }
   format_size = KMP_STRLEN(__kmp_affinity_format);
   if (buffer && size) {
     __kmp_fortran_strncpy_truncate(buffer, size, __kmp_affinity_format,
                                    format_size);
   }
   return format_size;
 #endif
 }
 
 /*
  * Prints the thread affinity information of the current thread in the format
  * specified by the format argument. If the format is NULL or a zero-length
  * string, the value of the affinity-format-var ICV is used.
  */
-void FTN_STDCALL FTN_DISPLAY_AFFINITY(char const *format, size_t size) {
+void FTN_STDCALL KMP_EXPAND_NAME_IF_APPEND(FTN_DISPLAY_AFFINITY)(
+    char const *format, size_t size) {
 #ifdef KMP_STUB
   return;
 #else
   int gtid;
   if (!TCR_4(__kmp_init_middle)) {
     __kmp_middle_initialize();
   }
   gtid = __kmp_get_gtid();
   ConvertedString cformat(format, size);
   __kmp_aux_display_affinity(gtid, cformat.get());
 #endif
 }
 
 /*
  * Returns the number of characters required to hold the entire affinity format
  * specification (not including null byte) and prints the thread affinity
  * information of the current thread into the character string buffer with the
  * size of size in the format specified by the format argument. If the format is
  * NULL or a zero-length string, the value of the affinity-format-var ICV is
  * used. The buffer must be allocated prior to calling the routine. If the
  * return value is larger than size, the affinity format specification is
  * truncated.
  */
-size_t FTN_STDCALL FTN_CAPTURE_AFFINITY(char *buffer, char const *format,
-                                        size_t buf_size, size_t for_size) {
+size_t FTN_STDCALL KMP_EXPAND_NAME_IF_APPEND(FTN_CAPTURE_AFFINITY)(
+    char *buffer, char const *format, size_t buf_size, size_t for_size) {
 #if defined(KMP_STUB)
   return 0;
 #else
   int gtid;
   size_t num_required;
   kmp_str_buf_t capture_buf;
   if (!TCR_4(__kmp_init_middle)) {
     __kmp_middle_initialize();
__kmp_entry_thread()->th.th_current_task->td_icvs.default_device =
       KMP_DEREF arg;
 #endif
 }
 
 // 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_EXTERNAL;
 int FTN_STDCALL KMP_EXPAND_NAME(FTN_GET_NUM_DEVICES)(void) {
 #if KMP_MIC || KMP_OS_DARWIN || defined(KMP_STUB)
   return 0;
 #else
   int (*fptr)();
   if ((*(void **)(&fptr) = KMP_DLSYM("__tgt_get_num_devices"))) {
     return (*fptr)();
   } else if ((*(void **)(&fptr) = KMP_DLSYM_NEXT("omp_get_num_devices"))) {
     return (*fptr)();
   } else if ((*(void **)(&fptr) = KMP_DLSYM("_Offload_number_of_devices"))) {
     return (*fptr)();
   } else { // liboffload & libomptarget don't exist
     return 0;
   }
 #endif // KMP_MIC || KMP_OS_DARWIN || KMP_OS_WINDOWS || defined(KMP_STUB)
 }
 
 // This function always returns true when called on host device.
 // Compiler/libomptarget should handle when it is called inside target region.
 int FTN_STDCALL KMP_EXPAND_NAME(FTN_IS_INITIAL_DEVICE)(void)
     KMP_WEAK_ATTRIBUTE_EXTERNAL;
 int FTN_STDCALL KMP_EXPAND_NAME(FTN_IS_INITIAL_DEVICE)(void) {
   return 1; // This is the host
 }
 
 // libomptarget, if loaded, provides this function
 int FTN_STDCALL KMP_EXPAND_NAME(FTN_GET_INITIAL_DEVICE)(void)
     KMP_WEAK_ATTRIBUTE_EXTERNAL;
 int FTN_STDCALL KMP_EXPAND_NAME(FTN_GET_INITIAL_DEVICE)(void) {
   // same as omp_get_num_devices()
   return KMP_EXPAND_NAME(FTN_GET_NUM_DEVICES)();
 }
 
 #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; }
#else
   return __kmp_max_task_priority;
 #endif
 }
 
 // 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_EXTERNAL;
 int FTN_STDCALL FTN_GET_DEVICE_NUM(void) {
   return KMP_EXPAND_NAME(FTN_GET_INITIAL_DEVICE)();
 }
 
 // Compiler will ensure that this is only called from host in sequential region
-int FTN_STDCALL FTN_PAUSE_RESOURCE(kmp_pause_status_t kind, int device_num) {
+int FTN_STDCALL KMP_EXPAND_NAME(FTN_PAUSE_RESOURCE)(kmp_pause_status_t kind,
+                                                    int device_num) {
 #ifdef KMP_STUB
   return 1; // just fail
 #else
   if (device_num == KMP_EXPAND_NAME(FTN_GET_INITIAL_DEVICE)())
     return __kmpc_pause_resource(kind);
   else {
     int (*fptr)(kmp_pause_status_t, int);
     if ((*(void **)(&fptr) = KMP_DLSYM("tgt_pause_resource")))
       return (*fptr)(kind, device_num);
     else
       return 1; // just fail if there is no libomptarget
   }
 #endif
 }
 
 // Compiler will ensure that this is only called from host in sequential region
-int FTN_STDCALL FTN_PAUSE_RESOURCE_ALL(kmp_pause_status_t kind) {
+int FTN_STDCALL
+    KMP_EXPAND_NAME(FTN_PAUSE_RESOURCE_ALL)(kmp_pause_status_t kind) {
 #ifdef KMP_STUB
   return 1; // just fail
 #else
   int fails = 0;
   int (*fptr)(kmp_pause_status_t, int);
   if ((*(void **)(&fptr) = KMP_DLSYM("tgt_pause_resource")))
     fails = (*fptr)(kind, KMP_DEVICE_ALL); // pause devices
   fails += __kmpc_pause_resource(kind); // pause host
/* These following sections create versioned symbols for the
    Step 2) Set __kmp_api_omp_set_num_threads_10_alias to version:
      omp_set_num_threads@OMP_1.0
    Step 2B) Set __kmp_api_omp_set_num_threads to default version:
      omp_set_num_threads@@VERSION
 */
 
 // OMP_1.0 versioned symbols
 KMP_VERSION_SYMBOL(FTN_SET_NUM_THREADS, 10, "OMP_1.0");
 KMP_VERSION_SYMBOL(FTN_GET_NUM_THREADS, 10, "OMP_1.0");
 KMP_VERSION_SYMBOL(FTN_GET_MAX_THREADS, 10, "OMP_1.0");
 KMP_VERSION_SYMBOL(FTN_GET_THREAD_NUM, 10, "OMP_1.0");
 KMP_VERSION_SYMBOL(FTN_GET_NUM_PROCS, 10, "OMP_1.0");
 KMP_VERSION_SYMBOL(FTN_IN_PARALLEL, 10, "OMP_1.0");
 KMP_VERSION_SYMBOL(FTN_SET_DYNAMIC, 10, "OMP_1.0");
 KMP_VERSION_SYMBOL(FTN_GET_DYNAMIC, 10, "OMP_1.0");
 KMP_VERSION_SYMBOL(FTN_SET_NESTED, 10, "OMP_1.0");
 KMP_VERSION_SYMBOL(FTN_GET_NESTED, 10, "OMP_1.0");
 KMP_VERSION_SYMBOL(FTN_INIT_LOCK, 10, "OMP_1.0");

 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");
 
 // OMP_5.0 versioned symbols
 // KMP_VERSION_SYMBOL(FTN_GET_DEVICE_NUM, 50, "OMP_5.0");
-// KMP_VERSION_SYMBOL(FTN_PAUSE_RESOURCE, 50, "OMP_5.0");
-// KMP_VERSION_SYMBOL(FTN_PAUSE_RESOURCE_ALL, 50, "OMP_5.0");
+KMP_VERSION_SYMBOL(FTN_PAUSE_RESOURCE, 50, "OMP_5.0");
+KMP_VERSION_SYMBOL(FTN_PAUSE_RESOURCE_ALL, 50, "OMP_5.0");
+// The C versions (KMP_FTN_PLAIN) of these symbols are in kmp_csupport.c
+#if KMP_FTN_ENTRIES == KMP_FTN_APPEND
+KMP_VERSION_SYMBOL(FTN_CAPTURE_AFFINITY, 50, "OMP_5.0");
+KMP_VERSION_SYMBOL(FTN_DISPLAY_AFFINITY, 50, "OMP_5.0");
+KMP_VERSION_SYMBOL(FTN_GET_AFFINITY_FORMAT, 50, "OMP_5.0");
+KMP_VERSION_SYMBOL(FTN_SET_AFFINITY_FORMAT, 50, "OMP_5.0");
+#endif
 // KMP_VERSION_SYMBOL(FTN_GET_SUPPORTED_ACTIVE_LEVELS, 50, "OMP_5.0");
 // KMP_VERSION_SYMBOL(FTN_FULFILL_EVENT, 50, "OMP_5.0");
 
 #endif // KMP_USE_VERSION_SYMBOLS
 
 #ifdef __cplusplus
 } // extern "C"
 #endif // __cplusplus
 
 // end of file //

openmp/runtime/src/kmp_os.h

 #define _KMP_VERSION_SYMBOL(api_name, ver_num, ver_str, default_ver)            \
   __typeof__(__kmp_api_##api_name) __kmp_api_##api_name##_##ver_num##_alias     \
       __attribute__((alias(KMP_STR(__kmp_api_##api_name))));                    \
   __asm__(                                                                      \
       ".symver " KMP_STR(__kmp_api_##api_name##_##ver_num##_alias) "," KMP_STR( \
           api_name) "@" ver_str "\n\t");                                        \
   __asm__(".symver " KMP_STR(__kmp_api_##api_name) "," KMP_STR(                 \
       api_name) "@@" default_ver "\n\t")
+
+#define KMP_VERSION_OMPC_SYMBOL(apic_name, api_name, ver_num, ver_str)         \
+  _KMP_VERSION_OMPC_SYMBOL(apic_name, api_name, ver_num, ver_str, "VERSION")
+#define _KMP_VERSION_OMPC_SYMBOL(apic_name, api_name, ver_num, ver_str,          \
+                                 default_ver)                                    \
+  __typeof__(__kmp_api_##apic_name) __kmp_api_##apic_name##_##ver_num##_alias    \
+      __attribute__((alias(KMP_STR(__kmp_api_##apic_name))));                    \
+  __asm__(".symver " KMP_STR(__kmp_api_##apic_name) "," KMP_STR(                 \
+      apic_name) "@@" default_ver "\n\t");                                       \
+  __asm__(                                                                       \
+      ".symver " KMP_STR(__kmp_api_##apic_name##_##ver_num##_alias) "," KMP_STR( \
+          api_name) "@" ver_str "\n\t")
+
 #else // KMP_USE_VERSION_SYMBOLS
 #define KMP_EXPAND_NAME(api_name) api_name
 #define KMP_VERSION_SYMBOL(api_name, ver_num, ver_str) /* Nothing */
+#define KMP_VERSION_OMPC_SYMBOL(apic_name, api_name, ver_num,                  \
+                                ver_str) /* Nothing */
 #endif // KMP_USE_VERSION_SYMBOLS
 
 /* Temporary note: if performance testing of this passes, we can remove
    all references to KMP_DO_ALIGN and replace with KMP_ALIGN.  */
 #define KMP_DO_ALIGN(bytes) KMP_ALIGN(bytes)
 #define KMP_ALIGN_CACHE KMP_ALIGN(CACHE_LINE)
 #define KMP_ALIGN_CACHE_INTERNODE KMP_ALIGN(INTERNODE_CACHE_LINE)