[libomptarget] Move header files and CMake library definition

[Hahnfeld]

Summary

Future patches will add (private) header files in src/ that should
not be visible to plugins, so move the "public" ones to a new
include/ directory. This is still internal in a sense that the
contained files won't be installed for the user.
Similarly, the target agnostic offloading library should be built
directly in src/. The parent directory is responsible for finding
dependencies and including all subdirectories.

[grokos]

LGTM.

[grokos]

libomptarget/include/omptarget.h

52

Before committing, can you fix this typo? The member is given by the 4 most significant hex digits, i.e. 16 MSBs, not 4 MSBs.

libomptarget/CMakeLists.txt

 ##===----------------------------------------------------------------------===##
 # 
 #                     The LLVM Compiler Infrastructure
 #
 # This file is dual licensed under the MIT and the University of Illinois Open
 # Source Licenses. See LICENSE.txt for details.
 # 
 ##===----------------------------------------------------------------------===##
 #
-# Build offloading library libomptarget.so.
+# Build offloading library and related plugins.
 #
 ##===----------------------------------------------------------------------===##
 
 if("${CMAKE_SOURCE_DIR}" STREQUAL "${CMAKE_CURRENT_SOURCE_DIR}")
   message(FATAL_ERROR "Direct configuration not supported, please use parent directory!")
 endif()
 
 # Add cmake directory to search for custom cmake functions.

 # Once the plugins for the different targets are validated, they will be added to
 # the list of supported targets in the current system.
 set (LIBOMPTARGET_SYSTEM_TARGETS "")
 
 # Set base directories - required for lit to locate the tests.
 set(LIBOMPTARGET_BASE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
 set(LIBOMPTARGET_BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR})
 
-libomptarget_say("Building offloading runtime library libomptarget.")
-
 # If building this library in debug mode, we define a macro to enable
 # dumping progress messages at runtime.
 string( TOLOWER "${CMAKE_BUILD_TYPE}" LIBOMPTARGET_CMAKE_BUILD_TYPE)
 if(LIBOMPTARGET_CMAKE_BUILD_TYPE MATCHES debug)
   add_definitions(-DOMPTARGET_DEBUG)
   add_definitions(-g)
   add_definitions(-O0)
 endif()
 
-set(src_files
-  src/omptarget.cpp
-)
-
-include_directories(src/)
-
-# Build libomptarget library with libdl dependency.
-add_library(omptarget SHARED ${src_files})
-target_link_libraries(omptarget
-  ${CMAKE_DL_LIBS}
-  "-Wl,--version-script=${CMAKE_CURRENT_SOURCE_DIR}/exports")
+include_directories(include)
 
-# Install libomptarget under the lib destination folder.
-install(TARGETS omptarget LIBRARY DESTINATION lib${OPENMP_LIBDIR_SUFFIX})
+# Build target agnostic offloading library.
+add_subdirectory(src)
 
 # Retrieve the path to the resulting library so that it can be used for 
 # testing.
 get_target_property(LIBOMPTARGET_LIBRARY_DIR omptarget LIBRARY_OUTPUT_DIRECTORY)
 if(NOT LIBOMPTARGET_LIBRARY_DIR)
   set(LIBOMPTARGET_LIBRARY_DIR ${CMAKE_CURRENT_BINARY_DIR})
 endif()
 
 # Build offloading plugins and device RTLs if they are available.
 add_subdirectory(plugins)
 
 # Add tests.
 add_subdirectory(test)

libomptarget/exports

-VERS1.0 {
-  global:
-    __tgt_register_lib;
-    __tgt_unregister_lib;
-    __tgt_target_data_begin;
-    __tgt_target_data_end;
-    __tgt_target_data_update;
-    __tgt_target;
-    __tgt_target_teams;
-    __tgt_target_data_begin_nowait;
-    __tgt_target_data_end_nowait;
-    __tgt_target_data_update_nowait;
-    __tgt_target_nowait;
-    __tgt_target_teams_nowait;
-    omp_get_num_devices;
-    omp_get_initial_device;
-    omp_target_alloc;
-    omp_target_free;
-    omp_target_is_present;
-    omp_target_memcpy;
-    omp_target_memcpy_rect;
-    omp_target_associate_ptr;
-    omp_target_disassociate_ptr;
-    __kmpc_push_target_tripcount;
-  local:
-    *;
-};
-

libomptarget/include/omptarget.h

+//===-------- omptarget.h - Target independent OpenMP target RTL -- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.txt for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Interface to be used by Clang during the codegen of a
+// target region.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _OMPTARGET_H_
+#define _OMPTARGET_H_
+
+#include <stdint.h>
+#include <stddef.h>
+
+#define OFFLOAD_SUCCESS (0)
+#define OFFLOAD_FAIL (~0)
+
+#define OFFLOAD_DEVICE_DEFAULT     -1
+#define HOST_DEVICE                -10
+
+/// Data attributes for each data reference used in an OpenMP target region.
+enum tgt_map_type {
+  // No flags
+  OMP_TGT_MAPTYPE_NONE            = 0x000,
+  // copy data from host to device
+  OMP_TGT_MAPTYPE_TO              = 0x001,
+  // copy data from device to host
+  OMP_TGT_MAPTYPE_FROM            = 0x002,
+  // copy regardless of the reference count
+  OMP_TGT_MAPTYPE_ALWAYS          = 0x004,
+  // force unmapping of data
+  OMP_TGT_MAPTYPE_DELETE          = 0x008,
+  // map the pointer as well as the pointee
+  OMP_TGT_MAPTYPE_PTR_AND_OBJ     = 0x010,
+  // pass device base address to kernel
+  OMP_TGT_MAPTYPE_TARGET_PARAM    = 0x020,
+  // return base device address of mapped data
+  OMP_TGT_MAPTYPE_RETURN_PARAM    = 0x040,
+  // private variable - not mapped
+  OMP_TGT_MAPTYPE_PRIVATE         = 0x080,
+  // copy by value - not mapped
+  OMP_TGT_MAPTYPE_LITERAL         = 0x100,
+  // mapping is implicit
+  OMP_TGT_MAPTYPE_IMPLICIT        = 0x200,
+  // member of struct, member given by 16 MSBs - 1
+  OMP_TGT_MAPTYPE_MEMBER_OF       = 0xffff000000000000
+};
+
+enum OpenMPOffloadingDeclareTargetFlags {
+  /// Mark the entry as having a 'link' attribute.
+  OMP_DECLARE_TARGET_LINK = 0x01,
+  /// Mark the entry as being a global constructor.
+  OMP_DECLARE_TARGET_CTOR = 0x02,
+  /// Mark the entry as being a global destructor.
+  OMP_DECLARE_TARGET_DTOR = 0x04
+};
+
+/// This struct is a record of an entry point or global. For a function
+/// entry point the size is expected to be zero
+struct __tgt_offload_entry {
+  void *addr;   // Pointer to the offload entry info (function or global)
+  char *name;   // Name of the function or global
+  size_t size;  // Size of the entry info (0 if it is a function)
+  int32_t flags; // Flags associated with the entry, e.g. 'link'.
+  int32_t reserved; // Reserved, to be used by the runtime library.
+};
+
+/// This struct is a record of the device image information
+struct __tgt_device_image {
+  void *ImageStart;                  // Pointer to the target code start
+  void *ImageEnd;                    // Pointer to the target code end
+  __tgt_offload_entry *EntriesBegin; // Begin of table with all target entries
+  __tgt_offload_entry *EntriesEnd;   // End of table (non inclusive)
+};
+
+/// This struct is a record of all the host code that may be offloaded to a
+/// target.
+struct __tgt_bin_desc {
+  int32_t NumDeviceImages;           // Number of device types supported
+  __tgt_device_image *DeviceImages;  // Array of device images (1 per dev. type)
+  __tgt_offload_entry *HostEntriesBegin; // Begin of table with all host entries
+  __tgt_offload_entry *HostEntriesEnd;   // End of table (non inclusive)
+};
+
+/// This struct contains the offload entries identified by the target runtime
+struct __tgt_target_table {
+  __tgt_offload_entry *EntriesBegin; // Begin of the table with all the entries
+  __tgt_offload_entry
+      *EntriesEnd; // End of the table with all the entries (non inclusive)
+};
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Implemented in libomp, they are called from within __tgt_* functions.
+int omp_get_default_device(void) __attribute__((weak));
+int32_t __kmpc_omp_taskwait(void *loc_ref, int32_t gtid) __attribute__((weak));
+
+int omp_get_num_devices(void);
+int omp_get_initial_device(void);
+void *omp_target_alloc(size_t size, int device_num);
+void omp_target_free(void *device_ptr, int device_num);
+int omp_target_is_present(void *ptr, int device_num);
+int omp_target_memcpy(void *dst, void *src, size_t length, size_t dst_offset,
+    size_t src_offset, int dst_device, int src_device);
+int omp_target_memcpy_rect(void *dst, void *src, size_t element_size,
+    int num_dims, const size_t *volume, const size_t *dst_offsets,
+    const size_t *src_offsets, const size_t *dst_dimensions,
+    const size_t *src_dimensions, int dst_device, int src_device);
+int omp_target_associate_ptr(void *host_ptr, void *device_ptr, size_t size,
+    size_t device_offset, int device_num);
+int omp_target_disassociate_ptr(void *host_ptr, int device_num);
+
+/// adds a target shared library to the target execution image
+void __tgt_register_lib(__tgt_bin_desc *desc);
+
+/// removes a target shared library from the target execution image
+void __tgt_unregister_lib(__tgt_bin_desc *desc);
+
+// creates the host to target data mapping, stores it in the
+// libomptarget.so internal structure (an entry in a stack of data maps) and
+// passes the data to the device;
+void __tgt_target_data_begin(int64_t device_id, int32_t arg_num,
+                             void **args_base, void **args, int64_t *arg_sizes,
+                             int64_t *arg_types);
+void __tgt_target_data_begin_nowait(int64_t device_id, int32_t arg_num,
+                                    void **args_base, void **args,
+                                    int64_t *arg_sizes, int64_t *arg_types,
+                                    int32_t depNum, void *depList,
+                                    int32_t noAliasDepNum,
+                                    void *noAliasDepList);
+
+// passes data from the target, release target memory and destroys the
+// host-target mapping (top entry from the stack of data maps) created by
+// the last __tgt_target_data_begin
+void __tgt_target_data_end(int64_t device_id, int32_t arg_num, void **args_base,
+                           void **args, int64_t *arg_sizes, int64_t *arg_types);
+void __tgt_target_data_end_nowait(int64_t device_id, int32_t arg_num,
+                                  void **args_base, void **args,
+                                  int64_t *arg_sizes, int64_t *arg_types,
+                                  int32_t depNum, void *depList,
+                                  int32_t noAliasDepNum, void *noAliasDepList);
+
+/// passes data to/from the target
+void __tgt_target_data_update(int64_t device_id, int32_t arg_num,
+                              void **args_base, void **args, int64_t *arg_sizes,
+                              int64_t *arg_types);
+void __tgt_target_data_update_nowait(int64_t device_id, int32_t arg_num,
+                                     void **args_base, void **args,
+                                     int64_t *arg_sizes, int64_t *arg_types,
+                                     int32_t depNum, void *depList,
+                                     int32_t noAliasDepNum,
+                                     void *noAliasDepList);
+
+// Performs the same actions as data_begin in case arg_num is non-zero
+// and initiates run of offloaded region on target platform; if arg_num
+// is non-zero after the region execution is done it also performs the
+// same action as data_end above. The following types are used; this
+// function returns 0 if it was able to transfer the execution to a
+// target and an int different from zero otherwise.
+int __tgt_target(int64_t device_id, void *host_ptr, int32_t arg_num,
+                 void **args_base, void **args, int64_t *arg_sizes,
+                 int64_t *arg_types);
+int __tgt_target_nowait(int64_t device_id, void *host_ptr, int32_t arg_num,
+                        void **args_base, void **args, int64_t *arg_sizes,
+                        int64_t *arg_types, int32_t depNum, void *depList,
+                        int32_t noAliasDepNum, void *noAliasDepList);
+
+int __tgt_target_teams(int64_t device_id, void *host_ptr, int32_t arg_num,
+                       void **args_base, void **args, int64_t *arg_sizes,
+                       int64_t *arg_types, int32_t num_teams,
+                       int32_t thread_limit);
+int __tgt_target_teams_nowait(int64_t device_id, void *host_ptr,
+                              int32_t arg_num, void **args_base, void **args,
+                              int64_t *arg_sizes, int64_t *arg_types,
+                              int32_t num_teams, int32_t thread_limit,
+                              int32_t depNum, void *depList,
+                              int32_t noAliasDepNum, void *noAliasDepList);
+void __kmpc_push_target_tripcount(int64_t device_id, uint64_t loop_tripcount);
+
+#ifdef __cplusplus
+}
+#endif
+
+#ifdef OMPTARGET_DEBUG
+#include <stdio.h>
+#define DEBUGP(prefix, ...)                                                    \
+  {                                                                            \
+    fprintf(stderr, "%s --> ", prefix);                                        \
+    fprintf(stderr, __VA_ARGS__);                                              \
+  }
+
+#ifndef __STDC_FORMAT_MACROS
+#define __STDC_FORMAT_MACROS
+#endif
+
+#include <inttypes.h>
+#define DPxMOD "0x%0*" PRIxPTR
+#define DPxPTR(ptr) ((int)(2*sizeof(uintptr_t))), ((uintptr_t) (ptr))
+
+/*
+ * To printf a pointer in hex with a fixed width of 16 digits and a leading 0x,
+ * use printf("ptr=" DPxMOD "...\n", DPxPTR(ptr));
+ *
+ * DPxMOD expands to:
+ *   "0x%0*" PRIxPTR
+ * where PRIxPTR expands to an appropriate modifier for the type uintptr_t on a
+ * specific platform, e.g. "lu" if uintptr_t is typedef'd as unsigned long:
+ *   "0x%0*lu"
+ *
+ * Ultimately, the whole statement expands to:
+ *   printf("ptr=0x%0*lu...\n",  // the 0* modifier expects an extra argument
+ *                               // specifying the width of the output
+ *   (int)(2*sizeof(uintptr_t)), // the extra argument specifying the width
+ *                               // 8 digits for 32bit systems
+ *                               // 16 digits for 64bit
+ *   (uintptr_t) ptr);
+ */
+#else
+#define DEBUGP(prefix, ...)                                                    \
+  {}
+#endif
+
+#ifdef __cplusplus
+#define EXTERN extern "C"
+#else
+#define EXTERN extern
+#endif
+
+#endif // _OMPTARGET_H_

libomptarget/include/omptargetplugin.h

+//===-- omptargetplugin.h - Target dependent OpenMP Plugin API --*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.txt for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines an interface between target independent OpenMP offload
+// runtime library libomptarget and target dependent plugin.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _OMPTARGETPLUGIN_H_
+#define _OMPTARGETPLUGIN_H_
+
+#include <omptarget.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Return the number of available devices of the type supported by the
+// target RTL.
+int32_t __tgt_rtl_number_of_devices(void);
+
+// Return an integer different from zero if the provided device image can be
+// supported by the runtime. The functionality is similar to comparing the
+// result of __tgt__rtl__load__binary to NULL. However, this is meant to be a
+// lightweight query to determine if the RTL is suitable for an image without
+// having to load the library, which can be expensive.
+int32_t __tgt_rtl_is_valid_binary(__tgt_device_image *Image);
+
+// Initialize the specified device. In case of success return 0; otherwise
+// return an error code.
+int32_t __tgt_rtl_init_device(int32_t ID);
+
+// Pass an executable image section described by image to the specified
+// device and prepare an address table of target entities. In case of error,
+// return NULL. Otherwise, return a pointer to the built address table.
+// Individual entries in the table may also be NULL, when the corresponding
+// offload region is not supported on the target device.
+__tgt_target_table *__tgt_rtl_load_binary(int32_t ID,
+                                          __tgt_device_image *Image);
+
+// Allocate data on the particular target device, of the specified size.
+// HostPtr is a address of the host data the allocated target data
+// will be associated with (HostPtr may be NULL if it is not known at
+// allocation time, like for example it would be for target data that
+// is allocated by omp_target_alloc() API). Return address of the
+// allocated data on the target that will be used by libomptarget.so to
+// initialize the target data mapping structures. These addresses are
+// used to generate a table of target variables to pass to
+// __tgt_rtl_run_region(). The __tgt_rtl_data_alloc() returns NULL in
+// case an error occurred on the target device.
+void *__tgt_rtl_data_alloc(int32_t ID, int64_t Size, void *HostPtr);
+
+// Pass the data content to the target device using the target address.
+// In case of success, return zero. Otherwise, return an error code.
+int32_t __tgt_rtl_data_submit(int32_t ID, void *TargetPtr, void *HostPtr,
+                              int64_t Size);
+
+// Retrieve the data content from the target device using its address.
+// In case of success, return zero. Otherwise, return an error code.
+int32_t __tgt_rtl_data_retrieve(int32_t ID, void *HostPtr, void *TargetPtr,
+                                int64_t Size);
+
+// De-allocate the data referenced by target ptr on the device. In case of
+// success, return zero. Otherwise, return an error code.
+int32_t __tgt_rtl_data_delete(int32_t ID, void *TargetPtr);
+
+// Transfer control to the offloaded entry Entry on the target device.
+// Args and Offsets are arrays of NumArgs size of target addresses and
+// offsets. An offset should be added to the target address before passing it
+// to the outlined function on device side. In case of success, return zero.
+// Otherwise, return an error code.
+int32_t __tgt_rtl_run_target_region(int32_t ID, void *Entry, void **Args,
+                                    ptrdiff_t *Offsets, int32_t NumArgs);
+
+// Similar to __tgt_rtl_run_target_region, but additionally specify the
+// number of teams to be created and a number of threads in each team.
+int32_t __tgt_rtl_run_target_team_region(int32_t ID, void *Entry, void **Args,
+                                         ptrdiff_t *Offsets, int32_t NumArgs,
+                                         int32_t NumTeams, int32_t ThreadLimit,
+                                         uint64_t loop_tripcount);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // _OMPTARGETPLUGIN_H_

libomptarget/src/CMakeLists.txt

+##===----------------------------------------------------------------------===##
+# 
+#                     The LLVM Compiler Infrastructure
+#
+# This file is dual licensed under the MIT and the University of Illinois Open
+# Source Licenses. See LICENSE.txt for details.
+# 
+##===----------------------------------------------------------------------===##
+#
+# Build offloading library libomptarget.so.
+#
+##===----------------------------------------------------------------------===##
+
+libomptarget_say("Building offloading runtime library libomptarget.")
+
+set(src_files
+  omptarget.cpp
+)
+
+# Build libomptarget library with libdl dependency.
+add_library(omptarget SHARED ${src_files})
+target_link_libraries(omptarget
+  ${CMAKE_DL_LIBS}
+  "-Wl,--version-script=${CMAKE_CURRENT_SOURCE_DIR}/exports")
+
+# Install libomptarget under the lib destination folder.
+install(TARGETS omptarget LIBRARY DESTINATION lib${OPENMP_LIBDIR_SUFFIX})

libomptarget/src/exports

+VERS1.0 {
+  global:
+    __tgt_register_lib;
+    __tgt_unregister_lib;
+    __tgt_target_data_begin;
+    __tgt_target_data_end;
+    __tgt_target_data_update;
+    __tgt_target;
+    __tgt_target_teams;
+    __tgt_target_data_begin_nowait;
+    __tgt_target_data_end_nowait;
+    __tgt_target_data_update_nowait;
+    __tgt_target_nowait;
+    __tgt_target_teams_nowait;
+    omp_get_num_devices;
+    omp_get_initial_device;
+    omp_target_alloc;
+    omp_target_free;
+    omp_target_is_present;
+    omp_target_memcpy;
+    omp_target_memcpy_rect;
+    omp_target_associate_ptr;
+    omp_target_disassociate_ptr;
+    __kmpc_push_target_tripcount;
+  local:
+    *;
+};
+

libomptarget/src/omptarget.h

-//===-------- omptarget.h - Target independent OpenMP target RTL -- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.txt for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// Interface to be used by Clang during the codegen of a
-// target region.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef _OMPTARGET_H_
-#define _OMPTARGET_H_
-
-#include <stdint.h>
-#include <stddef.h>
-
-#define OFFLOAD_SUCCESS (0)
-#define OFFLOAD_FAIL (~0)
-
-#define OFFLOAD_DEVICE_DEFAULT     -1
-#define HOST_DEVICE                -10
-
-/// Data attributes for each data reference used in an OpenMP target region.
-enum tgt_map_type {
-  // No flags
-  OMP_TGT_MAPTYPE_NONE            = 0x000,
-  // copy data from host to device
-  OMP_TGT_MAPTYPE_TO              = 0x001,
-  // copy data from device to host
-  OMP_TGT_MAPTYPE_FROM            = 0x002,
-  // copy regardless of the reference count
-  OMP_TGT_MAPTYPE_ALWAYS          = 0x004,
-  // force unmapping of data
-  OMP_TGT_MAPTYPE_DELETE          = 0x008,
-  // map the pointer as well as the pointee
-  OMP_TGT_MAPTYPE_PTR_AND_OBJ     = 0x010,
-  // pass device base address to kernel
-  OMP_TGT_MAPTYPE_TARGET_PARAM    = 0x020,
-  // return base device address of mapped data
-  OMP_TGT_MAPTYPE_RETURN_PARAM    = 0x040,
-  // private variable - not mapped
-  OMP_TGT_MAPTYPE_PRIVATE         = 0x080,
-  // copy by value - not mapped
-  OMP_TGT_MAPTYPE_LITERAL         = 0x100,
-  // mapping is implicit
-  OMP_TGT_MAPTYPE_IMPLICIT        = 0x200,
-  // member of struct, member given by 4 MSBs - 1
-  OMP_TGT_MAPTYPE_MEMBER_OF       = 0xffff000000000000
-};
-
-enum OpenMPOffloadingDeclareTargetFlags {
-  /// Mark the entry as having a 'link' attribute.
-  OMP_DECLARE_TARGET_LINK = 0x01,
-  /// Mark the entry as being a global constructor.
-  OMP_DECLARE_TARGET_CTOR = 0x02,
-  /// Mark the entry as being a global destructor.
-  OMP_DECLARE_TARGET_DTOR = 0x04
-};
-
-/// This struct is a record of an entry point or global. For a function
-/// entry point the size is expected to be zero
-struct __tgt_offload_entry {
-  void *addr;   // Pointer to the offload entry info (function or global)
-  char *name;   // Name of the function or global
-  size_t size;  // Size of the entry info (0 if it is a function)
-  int32_t flags; // Flags associated with the entry, e.g. 'link'.
-  int32_t reserved; // Reserved, to be used by the runtime library.
-};
-
-/// This struct is a record of the device image information
-struct __tgt_device_image {
-  void *ImageStart;                  // Pointer to the target code start
-  void *ImageEnd;                    // Pointer to the target code end
-  __tgt_offload_entry *EntriesBegin; // Begin of table with all target entries
-  __tgt_offload_entry *EntriesEnd;   // End of table (non inclusive)
-};
-
-/// This struct is a record of all the host code that may be offloaded to a
-/// target.
-struct __tgt_bin_desc {
-  int32_t NumDeviceImages;           // Number of device types supported
-  __tgt_device_image *DeviceImages;  // Array of device images (1 per dev. type)
-  __tgt_offload_entry *HostEntriesBegin; // Begin of table with all host entries
-  __tgt_offload_entry *HostEntriesEnd;   // End of table (non inclusive)
-};
-
-/// This struct contains the offload entries identified by the target runtime
-struct __tgt_target_table {
-  __tgt_offload_entry *EntriesBegin; // Begin of the table with all the entries
-  __tgt_offload_entry
-      *EntriesEnd; // End of the table with all the entries (non inclusive)
-};
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-// Implemented in libomp, they are called from within __tgt_* functions.
-int omp_get_default_device(void) __attribute__((weak));
-int32_t __kmpc_omp_taskwait(void *loc_ref, int32_t gtid) __attribute__((weak));
-
-int omp_get_num_devices(void);
-int omp_get_initial_device(void);
-void *omp_target_alloc(size_t size, int device_num);
-void omp_target_free(void *device_ptr, int device_num);
-int omp_target_is_present(void *ptr, int device_num);
-int omp_target_memcpy(void *dst, void *src, size_t length, size_t dst_offset,
-    size_t src_offset, int dst_device, int src_device);
-int omp_target_memcpy_rect(void *dst, void *src, size_t element_size,
-    int num_dims, const size_t *volume, const size_t *dst_offsets,
-    const size_t *src_offsets, const size_t *dst_dimensions,
-    const size_t *src_dimensions, int dst_device, int src_device);
-int omp_target_associate_ptr(void *host_ptr, void *device_ptr, size_t size,
-    size_t device_offset, int device_num);
-int omp_target_disassociate_ptr(void *host_ptr, int device_num);
-
-/// adds a target shared library to the target execution image
-void __tgt_register_lib(__tgt_bin_desc *desc);
-
-/// removes a target shared library from the target execution image
-void __tgt_unregister_lib(__tgt_bin_desc *desc);
-
-// creates the host to target data mapping, stores it in the
-// libomptarget.so internal structure (an entry in a stack of data maps) and
-// passes the data to the device;
-void __tgt_target_data_begin(int64_t device_id, int32_t arg_num,
-                             void **args_base, void **args, int64_t *arg_sizes,
-                             int64_t *arg_types);
-void __tgt_target_data_begin_nowait(int64_t device_id, int32_t arg_num,
-                                    void **args_base, void **args,
-                                    int64_t *arg_sizes, int64_t *arg_types,
-                                    int32_t depNum, void *depList,
-                                    int32_t noAliasDepNum,
-                                    void *noAliasDepList);
-
-// passes data from the target, release target memory and destroys the
-// host-target mapping (top entry from the stack of data maps) created by
-// the last __tgt_target_data_begin
-void __tgt_target_data_end(int64_t device_id, int32_t arg_num, void **args_base,
-                           void **args, int64_t *arg_sizes, int64_t *arg_types);
-void __tgt_target_data_end_nowait(int64_t device_id, int32_t arg_num,
-                                  void **args_base, void **args,
-                                  int64_t *arg_sizes, int64_t *arg_types,
-                                  int32_t depNum, void *depList,
-                                  int32_t noAliasDepNum, void *noAliasDepList);
-
-/// passes data to/from the target
-void __tgt_target_data_update(int64_t device_id, int32_t arg_num,
-                              void **args_base, void **args, int64_t *arg_sizes,
-                              int64_t *arg_types);
-void __tgt_target_data_update_nowait(int64_t device_id, int32_t arg_num,
-                                     void **args_base, void **args,
-                                     int64_t *arg_sizes, int64_t *arg_types,
-                                     int32_t depNum, void *depList,
-                                     int32_t noAliasDepNum,
-                                     void *noAliasDepList);
-
-// Performs the same actions as data_begin in case arg_num is non-zero
-// and initiates run of offloaded region on target platform; if arg_num
-// is non-zero after the region execution is done it also performs the
-// same action as data_end above. The following types are used; this
-// function returns 0 if it was able to transfer the execution to a
-// target and an int different from zero otherwise.
-int __tgt_target(int64_t device_id, void *host_ptr, int32_t arg_num,
-                 void **args_base, void **args, int64_t *arg_sizes,
-                 int64_t *arg_types);
-int __tgt_target_nowait(int64_t device_id, void *host_ptr, int32_t arg_num,
-                        void **args_base, void **args, int64_t *arg_sizes,
-                        int64_t *arg_types, int32_t depNum, void *depList,
-                        int32_t noAliasDepNum, void *noAliasDepList);
-
-int __tgt_target_teams(int64_t device_id, void *host_ptr, int32_t arg_num,
-                       void **args_base, void **args, int64_t *arg_sizes,
-                       int64_t *arg_types, int32_t num_teams,
-                       int32_t thread_limit);
-int __tgt_target_teams_nowait(int64_t device_id, void *host_ptr,
-                              int32_t arg_num, void **args_base, void **args,
-                              int64_t *arg_sizes, int64_t *arg_types,
-                              int32_t num_teams, int32_t thread_limit,
-                              int32_t depNum, void *depList,
-                              int32_t noAliasDepNum, void *noAliasDepList);
-void __kmpc_push_target_tripcount(int64_t device_id, uint64_t loop_tripcount);
-
-#ifdef __cplusplus
-}
-#endif
-
-#ifdef OMPTARGET_DEBUG
-#include <stdio.h>
-#define DEBUGP(prefix, ...)                                                    \
-  {                                                                            \
-    fprintf(stderr, "%s --> ", prefix);                                        \
-    fprintf(stderr, __VA_ARGS__);                                              \
-  }
-
-#ifndef __STDC_FORMAT_MACROS
-#define __STDC_FORMAT_MACROS
-#endif
-
-#include <inttypes.h>
-#define DPxMOD "0x%0*" PRIxPTR
-#define DPxPTR(ptr) ((int)(2*sizeof(uintptr_t))), ((uintptr_t) (ptr))
-
-/*
- * To printf a pointer in hex with a fixed width of 16 digits and a leading 0x,
- * use printf("ptr=" DPxMOD "...\n", DPxPTR(ptr));
- *
- * DPxMOD expands to:
- *   "0x%0*" PRIxPTR
- * where PRIxPTR expands to an appropriate modifier for the type uintptr_t on a
- * specific platform, e.g. "lu" if uintptr_t is typedef'd as unsigned long:
- *   "0x%0*lu"
- *
- * Ultimately, the whole statement expands to:
- *   printf("ptr=0x%0*lu...\n",  // the 0* modifier expects an extra argument
- *                               // specifying the width of the output
- *   (int)(2*sizeof(uintptr_t)), // the extra argument specifying the width
- *                               // 8 digits for 32bit systems
- *                               // 16 digits for 64bit
- *   (uintptr_t) ptr);
- */
-#else
-#define DEBUGP(prefix, ...)                                                    \
-  {}
-#endif
-
-#ifdef __cplusplus
-#define EXTERN extern "C"
-#else
-#define EXTERN extern
-#endif
-
-#endif // _OMPTARGET_H_

libomptarget/src/omptargetplugin.h

-//===-- omptargetplugin.h - Target dependent OpenMP Plugin API --*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.txt for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file defines an interface between target independent OpenMP offload
-// runtime library libomptarget and target dependent plugin.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef _OMPTARGETPLUGIN_H_
-#define _OMPTARGETPLUGIN_H_
-
-#include <omptarget.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-// Return the number of available devices of the type supported by the
-// target RTL.
-int32_t __tgt_rtl_number_of_devices(void);
-
-// Return an integer different from zero if the provided device image can be
-// supported by the runtime. The functionality is similar to comparing the
-// result of __tgt__rtl__load__binary to NULL. However, this is meant to be a
-// lightweight query to determine if the RTL is suitable for an image without
-// having to load the library, which can be expensive.
-int32_t __tgt_rtl_is_valid_binary(__tgt_device_image *Image);
-
-// Initialize the specified device. In case of success return 0; otherwise
-// return an error code.
-int32_t __tgt_rtl_init_device(int32_t ID);
-
-// Pass an executable image section described by image to the specified
-// device and prepare an address table of target entities. In case of error,
-// return NULL. Otherwise, return a pointer to the built address table.
-// Individual entries in the table may also be NULL, when the corresponding
-// offload region is not supported on the target device.
-__tgt_target_table *__tgt_rtl_load_binary(int32_t ID,
-                                          __tgt_device_image *Image);
-
-// Allocate data on the particular target device, of the specified size.
-// HostPtr is a address of the host data the allocated target data
-// will be associated with (HostPtr may be NULL if it is not known at
-// allocation time, like for example it would be for target data that
-// is allocated by omp_target_alloc() API). Return address of the
-// allocated data on the target that will be used by libomptarget.so to
-// initialize the target data mapping structures. These addresses are
-// used to generate a table of target variables to pass to
-// __tgt_rtl_run_region(). The __tgt_rtl_data_alloc() returns NULL in
-// case an error occurred on the target device.
-void *__tgt_rtl_data_alloc(int32_t ID, int64_t Size, void *HostPtr);
-
-// Pass the data content to the target device using the target address.
-// In case of success, return zero. Otherwise, return an error code.
-int32_t __tgt_rtl_data_submit(int32_t ID, void *TargetPtr, void *HostPtr,
-                              int64_t Size);
-
-// Retrieve the data content from the target device using its address.
-// In case of success, return zero. Otherwise, return an error code.
-int32_t __tgt_rtl_data_retrieve(int32_t ID, void *HostPtr, void *TargetPtr,
-                                int64_t Size);
-
-// De-allocate the data referenced by target ptr on the device. In case of
-// success, return zero. Otherwise, return an error code.
-int32_t __tgt_rtl_data_delete(int32_t ID, void *TargetPtr);
-
-// Transfer control to the offloaded entry Entry on the target device.
-// Args and Offsets are arrays of NumArgs size of target addresses and
-// offsets. An offset should be added to the target address before passing it
-// to the outlined function on device side. In case of success, return zero.
-// Otherwise, return an error code.
-int32_t __tgt_rtl_run_target_region(int32_t ID, void *Entry, void **Args,
-                                    ptrdiff_t *Offsets, int32_t NumArgs);
-
-// Similar to __tgt_rtl_run_target_region, but additionally specify the
-// number of teams to be created and a number of threads in each team.
-int32_t __tgt_rtl_run_target_team_region(int32_t ID, void *Entry, void **Args,
-                                         ptrdiff_t *Offsets, int32_t NumArgs,
-                                         int32_t NumTeams, int32_t ThreadLimit,
-                                         uint64_t loop_tripcount);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif // _OMPTARGETPLUGIN_H_