[build] Update location of OpenMP libraries

By default, LLVM 19 installs libomp and libompd under
$CMAKE_INSTALL_PREFIX/lib/$LLVM_HOST_TARGET/. This patch updates CMake
and llvm-lit configurations to add the new location to the linker and
the loader's search paths.

Author: bryanpkc

CMakeLists.txt

@@ -83,7 +83,8 @@ if( CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR )
       "--bindir"
       "--libdir"
       "--includedir"
-      "--prefix")
+      "--prefix"
+      "--host-target")
     execute_process(
       COMMAND ${CONFIG_COMMAND}
       RESULT_VARIABLE HAD_ERROR
@@ -107,6 +108,7 @@ if( CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR )
   list(GET CONFIG_OUTPUT 2 LIBRARY_DIR)
   list(GET CONFIG_OUTPUT 3 INCLUDE_DIR)
   list(GET CONFIG_OUTPUT 4 LLVM_OBJ_ROOT)
+  list(GET CONFIG_OUTPUT 5 LLVM_HOST_TARGET)
 
   if(NOT MSVC_IDE)
     set(LLVM_ENABLE_ASSERTIONS ${ENABLE_ASSERTIONS}
@@ -158,7 +160,7 @@ if( CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR )
   endif()
 
   include_directories("${LLVM_BINARY_DIR}/include" "${LLVM_MAIN_INCLUDE_DIR}")
-  link_directories("${LLVM_LIBRARY_DIR}")
+  link_directories("${LLVM_LIBRARY_DIR}/${LLVM_HOST_TARGET}")
 
   set( CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin )
   set( CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib )

runtime/flangrti/CMakeLists.txt

@@ -108,7 +108,7 @@ if (NOT DEFINED LIBOMP_EXPORT_DIR)
   find_library(
     FLANG_LIBOMP
     NAMES omp libomp
-    HINTS ${CMAKE_BINARY_DIR}/lib)
+    HINTS "${LLVM_LIBRARY_DIR}/${LLVM_HOST_TARGET}")
   target_link_libraries(flangrti_shared PUBLIC ${FLANG_LIBOMP})
 endif()
 

test/lit.cfg

@@ -86,7 +86,11 @@ if flang_obj_root is not None:
     llvm_libs_dir = getattr(config, 'llvm_libs_dir', None)
     if not llvm_libs_dir:
         lit_config.fatal('No LLVM libs dir set!')
+    host_triple = getattr(config, 'host_triple', None)
+    if not host_triple:
+        lit_config.fatal('No LLVM host triple set!')
     path = os.path.pathsep.join((llvm_libs_dir,
+                                 os.path.sep.join((llvm_libs_dir, host_triple)),
                                  config.environment.get('LD_LIBRARY_PATH','')))
     config.environment['LD_LIBRARY_PATH'] = path