[Offload] Support standalone build for OpenMP and Offload

Moved some of the common functionality in a top-level common
cmake module and fixed path and inclusion issues.

Depends on #75125

Author: saiislam

cmake/Modules/OffloadOpenmpCommon.cmake

@@ -0,0 +1,68 @@
+# Check if OMPT support is available
+# Currently, __builtin_frame_address() is required for OMPT
+# Weak attribute is required for Unices (except Darwin), LIBPSAPI is used for Windows
+if(NOT LIBOMP_ARCH)
+  include(LibompGetArchitecture)
+  libomp_get_architecture(LIBOMP_DETECTED_ARCH)
+  set(LIBOMP_ARCH ${LIBOMP_DETECTED_ARCH})
+endif()
+
+check_c_source_compiles("int main(int argc, char** argv) {
+  void* p = __builtin_frame_address(0);
+  return 0;}" LIBOMP_HAVE___BUILTIN_FRAME_ADDRESS)
+check_c_source_compiles("__attribute__ ((weak)) int foo(int a) { return a*a; }
+  int main(int argc, char** argv) {
+  return foo(argc);}" LIBOMP_HAVE_WEAK_ATTRIBUTE)
+set(CMAKE_REQUIRED_LIBRARIES psapi)
+check_c_source_compiles("#include <windows.h>
+  #include <psapi.h>
+  int main(int artc, char** argv) {
+    return EnumProcessModules(NULL, NULL, 0, NULL);
+  }" LIBOMP_HAVE_PSAPI)
+set(CMAKE_REQUIRED_LIBRARIES)
+if(NOT LIBOMP_HAVE___BUILTIN_FRAME_ADDRESS)
+  set(LIBOMP_HAVE_OMPT_SUPPORT FALSE)
+else()
+  if( # hardware architecture supported?
+     ((LIBOMP_ARCH STREQUAL x86_64) OR
+      (LIBOMP_ARCH STREQUAL i386) OR
+#      (LIBOMP_ARCH STREQUAL arm) OR
+      (LIBOMP_ARCH STREQUAL aarch64) OR
+      (LIBOMP_ARCH STREQUAL aarch64_32) OR
+      (LIBOMP_ARCH STREQUAL aarch64_a64fx) OR
+      (LIBOMP_ARCH STREQUAL ppc64le) OR
+      (LIBOMP_ARCH STREQUAL ppc64) OR
+      (LIBOMP_ARCH STREQUAL riscv64) OR
+      (LIBOMP_ARCH STREQUAL loongarch64) OR
+      (LIBOMP_ARCH STREQUAL s390x))
+     AND # OS supported?
+     ((WIN32 AND LIBOMP_HAVE_PSAPI) OR APPLE OR
+      (NOT (WIN32 OR ${CMAKE_SYSTEM_NAME} MATCHES "AIX") AND LIBOMP_HAVE_WEAK_ATTRIBUTE)))
+    set(LIBOMP_HAVE_OMPT_SUPPORT TRUE)
+  else()
+    set(LIBOMP_HAVE_OMPT_SUPPORT FALSE)
+  endif()
+endif()
+
+# OMPT-support defaults to ON for OpenMP 5.0+ and if the requirements in
+# cmake/config-ix.cmake are fulfilled.
+set(OMPT_DEFAULT FALSE)
+if ((LIBOMP_HAVE_OMPT_SUPPORT) AND (NOT WIN32))
+  set(OMPT_DEFAULT TRUE)
+endif()
+set(LIBOMP_OMPT_SUPPORT ${OMPT_DEFAULT} CACHE BOOL
+  "OMPT-support?")
+
+# Check LIBOMP_HAVE_VERSION_SCRIPT_FLAG
+include(LLVMCheckCompilerLinkerFlag)
+if(NOT APPLE)
+  llvm_check_compiler_linker_flag(C "-Wl,--version-script=${CMAKE_CURRENT_LIST_DIR}/../../openmp/runtime/src/exports_test_so.txt" LIBOMP_HAVE_VERSION_SCRIPT_FLAG)
+endif()
+
+macro(pythonize_bool var)
+if (${var})
+  set(${var} True)
+else()
+  set(${var} False)
+endif()
+endmacro()

offload/CMakeLists.txt

@@ -10,6 +10,13 @@
 #
 ##===----------------------------------------------------------------------===##
 
+cmake_minimum_required(VERSION 3.20.0)
+
+if (OPENMP_STANDALONE_BUILD OR "${CMAKE_SOURCE_DIR}" STREQUAL "${CMAKE_CURRENT_SOURCE_DIR}")
+  set(OPENMP_STANDALONE_BUILD TRUE)
+  project(omptarget C CXX ASM)
+endif()
+
 set(ENABLE_LIBOMPTARGET ON)
 # Currently libomptarget cannot be compiled on Windows or MacOS X.
 # Since the device plugins are only supported on Linux anyway,
@@ -35,11 +42,12 @@ endif()
 # TODO: Leftover from the move, could probably be just LLVM_LIBDIR_SUFFIX everywhere.
 set(OFFLOAD_INSTALL_LIBDIR "lib${LLVM_LIBDIR_SUFFIX}")
 
-set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/cmake)
+set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
 
 # Add path for custom modules
 list(INSERT CMAKE_MODULE_PATH 0
   "${CMAKE_CURRENT_SOURCE_DIR}/cmake"
+  "${CMAKE_CURRENT_SOURCE_DIR}/cmake/Modules"
   "${LLVM_COMMON_CMAKE_UTILS}/Modules"
   )
 
@@ -190,6 +198,10 @@ if (LIBOMPTARGET_USE_LTO)
   list(APPEND offload_link_flags ${CMAKE_CXX_COMPILE_OPTIONS_IPO})
 endif()
 
+# Set LIBOMP_HAVE_OMPT_SUPPORT and LIBOMP_HAVE_VERSION_SCRIPT_FLAG using common offload/openmp cmake module.
+list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/../openmp/runtime/cmake")
+include(OffloadOpenmpCommon)
+
 # OMPT support for libomptarget
 # Follow host OMPT support and check if host support has been requested.
 # LIBOMP_HAVE_OMPT_SUPPORT indicates whether host OMPT support has been implemented.
@@ -214,6 +226,31 @@ set(LIBOMPTARGET_GPU_LIBC_SUPPORT ${LLVM_LIBC_GPU_BUILD} CACHE BOOL
     "Libomptarget support for the GPU libc")
 pythonize_bool(LIBOMPTARGET_GPU_LIBC_SUPPORT)
 
+if(OPENMP_STANDALONE_BUILD)
+  if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+    find_package(LLVM HINTS ${CMAKE_INSTALL_PREFIX})
+  endif()
+  find_path (
+    LIBOMP_OMP_TOOLS_INCLUDE_DIR
+    NAMES
+      omp-tools.h
+    HINTS
+    ${LLVM_INCLUDE_DIRS}
+    ${LLVM_INCLUDE_DIRS}/../lib/clang/${LLVM_VERSION_MAJOR}/include
+    ${CMAKE_INSTALL_PREFIX}/include
+    REQUIRED
+  )
+  find_library (
+    LIBOMP_STANDALONE
+    NAMES
+      omp
+    HINTS
+      ${LLVM_LIBRARY_DIRS}
+      ${CMAKE_INSTALL_PREFIX}/lib
+    REQUIRED
+  )
+endif()
+
 set(LIBOMPTARGET_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/include)
 message(STATUS "OpenMP tools dir in libomptarget: ${LIBOMP_OMP_TOOLS_INCLUDE_DIR}")
 include_directories(${LIBOMP_OMP_TOOLS_INCLUDE_DIR})

offload/plugins-nextgen/host/CMakeLists.txt

@@ -33,7 +33,7 @@ endif()
 
 # Install plugin under the lib destination folder.
 install(TARGETS omptarget.rtl.${machine}
-        LIBRARY DESTINATION "${OPENMP_INSTALL_LIBDIR}")
+        LIBRARY DESTINATION "${OFFLOAD_INSTALL_LIBDIR}")
 set_target_properties(omptarget.rtl.${machine} PROPERTIES
   INSTALL_RPATH "$ORIGIN" BUILD_RPATH "$ORIGIN:${CMAKE_CURRENT_BINARY_DIR}/.."
   POSITION_INDEPENDENT_CODE ON

offload/src/CMakeLists.txt

@@ -12,6 +12,12 @@
 
 libomptarget_say("Building offloading runtime library libomptarget.")
 
+if(LIBOMP_STANDALONE)
+  set(LIBOMP ${LIBOMP_STANDALONE})
+else()
+  set(LIBOMP omp)
+endif()
+
 add_llvm_library(omptarget
   SHARED
 
@@ -38,7 +44,7 @@ add_llvm_library(omptarget
 
   LINK_LIBS
   PUBLIC
-  omp
+  ${LIBOMP}
 
   NO_INSTALL_RPATH
   BUILDTREE_ONLY

openmp/CMakeLists.txt

@@ -113,7 +113,12 @@ option(OPENMP_ENABLE_LIBOMP_PROFILING "Enable time profiling for libomp." OFF)
 
 # Header install location
 if(${OPENMP_STANDALONE_BUILD})
-  set(LIBOMP_HEADERS_INSTALL_PATH "${CMAKE_INSTALL_INCLUDEDIR}")
+  if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+    find_package(LLVM HINTS ${CMAKE_INSTALL_PREFIX} REQUIRED)
+    set(LIBOMP_HEADERS_INSTALL_PATH "${LLVM_INCLUDE_DIRS}/../lib/clang/${LLVM_VERSION_MAJOR}/include")
+  else()
+    set(LIBOMP_HEADERS_INSTALL_PATH "${CMAKE_INSTALL_INCLUDEDIR}")
+  endif()
 else()
   include(GetClangResourceDir)
   get_clang_resource_dir(LIBOMP_HEADERS_INSTALL_PATH SUBDIR include)

openmp/runtime/cmake/config-ix.cmake

@@ -18,6 +18,7 @@ include(CheckIncludeFiles)
 include(CheckSymbolExists)
 include(LibompCheckFortranFlag)
 include(LLVMCheckCompilerLinkerFlag)
+include(OffloadOpenmpCommon)
 
 # Check for versioned symbols
 function(libomp_check_version_symbols retval)
@@ -132,7 +133,6 @@ if(WIN32)
 elseif(NOT APPLE)
   llvm_check_compiler_linker_flag(C -Wl,-x LIBOMP_HAVE_X_FLAG)
   llvm_check_compiler_linker_flag(C -Wl,--as-needed LIBOMP_HAVE_AS_NEEDED_FLAG)
-  llvm_check_compiler_linker_flag(C "-Wl,--version-script=${LIBOMP_SRC_DIR}/exports_test_so.txt" LIBOMP_HAVE_VERSION_SCRIPT_FLAG)
   llvm_check_compiler_linker_flag(C -static-libgcc LIBOMP_HAVE_STATIC_LIBGCC_FLAG)
   llvm_check_compiler_linker_flag(C -Wl,-z,noexecstack LIBOMP_HAVE_Z_NOEXECSTACK_FLAG)
 endif()
@@ -302,48 +302,6 @@ if(${LIBOMP_STATS})
   endif()
 endif()
 
-# Check if OMPT support is available
-# Currently, __builtin_frame_address() is required for OMPT
-# Weak attribute is required for Unices (except Darwin), LIBPSAPI is used for Windows
-check_c_source_compiles("int main(int argc, char** argv) {
-  void* p = __builtin_frame_address(0);
-  return 0;}" LIBOMP_HAVE___BUILTIN_FRAME_ADDRESS)
-check_c_source_compiles("__attribute__ ((weak)) int foo(int a) { return a*a; }
-  int main(int argc, char** argv) {
-  return foo(argc);}" LIBOMP_HAVE_WEAK_ATTRIBUTE)
-set(CMAKE_REQUIRED_LIBRARIES psapi)
-check_c_source_compiles("#include <windows.h>
-  #include <psapi.h>
-  int main(int artc, char** argv) {
-    return EnumProcessModules(NULL, NULL, 0, NULL);
-  }" LIBOMP_HAVE_PSAPI)
-set(CMAKE_REQUIRED_LIBRARIES)
-if(NOT LIBOMP_HAVE___BUILTIN_FRAME_ADDRESS)
-  set(LIBOMP_HAVE_OMPT_SUPPORT FALSE)
-else()
-  if( # hardware architecture supported?
-     ((LIBOMP_ARCH STREQUAL x86_64) OR
-      (LIBOMP_ARCH STREQUAL i386) OR
-#      (LIBOMP_ARCH STREQUAL arm) OR
-      (LIBOMP_ARCH STREQUAL aarch64) OR
-      (LIBOMP_ARCH STREQUAL aarch64_32) OR
-      (LIBOMP_ARCH STREQUAL aarch64_a64fx) OR
-      (LIBOMP_ARCH STREQUAL ppc64le) OR
-      (LIBOMP_ARCH STREQUAL ppc64) OR
-      (LIBOMP_ARCH STREQUAL riscv64) OR
-      (LIBOMP_ARCH STREQUAL loongarch64) OR
-      (LIBOMP_ARCH STREQUAL s390x))
-     AND # OS supported?
-     ((WIN32 AND LIBOMP_HAVE_PSAPI) OR APPLE OR
-      (NOT (WIN32 OR ${CMAKE_SYSTEM_NAME} MATCHES "AIX") AND LIBOMP_HAVE_WEAK_ATTRIBUTE)))
-    set(LIBOMP_HAVE_OMPT_SUPPORT TRUE)
-  else()
-    set(LIBOMP_HAVE_OMPT_SUPPORT FALSE)
-  endif()
-endif()
-
-set(LIBOMP_HAVE_OMPT_SUPPORT ${LIBOMP_HAVE_OMPT_SUPPORT} PARENT_SCOPE)
-
 # Check if HWLOC support is available
 if(${LIBOMP_USE_HWLOC})
   find_path(LIBOMP_HWLOC_INCLUDE_DIR NAMES hwloc.h HINTS ${LIBOMP_HWLOC_INSTALL_DIR} PATH_SUFFIXES include)