Support XPU ABI=0 build (#531)

# Motivation
Support XPU ABI neutral build.
Starting from compiler 2025.0, `libsycl.so` is ABI-neutral lib. Before
this, the `libsycl-preview.so` is ABI-neutral.

refer to pytorch/pytorch#130110

cmake/BuildFlags.cmake

@@ -59,10 +59,10 @@ if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" OR CMAKE_CXX_COMPILER_ID STREQUAL "MSVC"
     set(SYCL_KERNEL_OPTIONS ${SYCL_KERNEL_OPTIONS} -fno-approx-func)
     set(SYCL_KERNEL_OPTIONS ${SYCL_KERNEL_OPTIONS} -Wno-absolute-value)
     set(SYCL_KERNEL_OPTIONS ${SYCL_KERNEL_OPTIONS} -no-ftz)
+    # Equivalent to build option -fpreview-breaking-changes for SYCL compiler.
+    set(SYCL_KERNEL_OPTIONS ${SYCL_KERNEL_OPTIONS} -D__INTEL_PREVIEW_BREAKING_CHANGES)
+    set(SYCL_KERNEL_OPTIONS ${SYCL_KERNEL_OPTIONS} -D_GLIBCXX_USE_CXX11_ABI=${GLIBCXX_USE_CXX11_ABI})
   endif()
-  # TODO: Align with PyTorch and switch to ABI=0 eventually, after
-  # resolving incompatible implementation in SYCL runtime.
-  set(SYCL_KERNEL_OPTIONS ${SYCL_KERNEL_OPTIONS} -D_GLIBCXX_USE_CXX11_ABI=1)
   set(SYCL_FLAGS ${SYCL_FLAGS} ${SYCL_KERNEL_OPTIONS})
 
   set(TORCH_XPU_OPS_FLAGS ${SYCL_HOST_FLAGS})

cmake/Modules/FindSYCL.cmake

@@ -407,7 +407,6 @@ macro(SYCL_LINK_DEVICE_OBJECTS output_file sycl_target)
       OUTPUT ${output_file}
       DEPENDS ${object_files}
       COMMAND ${SYCL_EXECUTABLE}
-      -fsycl
       ${SYCL_device_link_flags}
       -fsycl-link ${object_files}
       -Xs "\"${SYCL_OFFLINE_COMPILER_FLAGS}\""
@@ -471,7 +470,7 @@ macro(SYCL_ADD_LIBRARY sycl_target)
   target_link_libraries(
     ${sycl_target}
     ${SYCL_LINK_LIBRARIES_KEYWORD}
-    ${SYCL_LIBRARIES})
+    ${SYCL_LIBRARY})
 
   set_target_properties(${sycl_target}
     PROPERTIES
@@ -530,7 +529,7 @@ macro(SYCL_ADD_EXECUTABLE sycl_target)
   target_link_libraries(
     ${sycl_target}
     ${SYCL_LINK_LIBRARIES_KEYWORD}
-    ${SYCL_LIBRARIES})
+    ${SYCL_LIBRARY})
 
   set_target_properties(${sycl_target}
     PROPERTIES

cmake/Modules/FindSYCLToolkit.cmake

@@ -25,16 +25,20 @@ This will define the following variables:
 
 #]=======================================================================]
 
-set(SYCLTOOLKIT_FOUND False)
-include(${CMAKE_ROOT}/Modules/FindPackageHandleStandardArgs.cmake)
+include(${TORCH_ROOT}/cmake/Modules/FindSYCLToolkit.cmake)
 
-set(SYCL_ROOT "")
-if(DEFINED ENV{SYCL_ROOT})
-  set(SYCL_ROOT $ENV{SYCL_ROOT})
-elseif(DEFINED ENV{CMPLR_ROOT})
-  set(SYCL_ROOT $ENV{CMPLR_ROOT})
+if(NOT SYCL_FOUND)
+  set(SYCLTOOLKIT_FOUND FALSE)
+  return()
 endif()
 
+if(SYCLTOOLKIT_FOUND)
+  return()
+endif()
+set(SYCLTOOLKIT_FOUND TRUE)
+
+include(${CMAKE_ROOT}/Modules/FindPackageHandleStandardArgs.cmake)
+
 if(WIN32)
   set(SYCL_EXECUTABLE_NAME icx)
 else()
@@ -71,43 +75,6 @@ if(nocmplr)
   set(SYCL_NOT_FOUND_MESSAGE "${SYCL_REASON_FAILURE}")
 endif()
 
-find_file(
-  SYCL_INCLUDE_DIR
-  NAMES include
-  HINTS ${SYCL_ROOT}
-  NO_DEFAULT_PATH
-  )
-
-find_file(
-  SYCL_INCLUDE_SYCL_DIR
-  NAMES sycl
-  HINTS ${SYCL_ROOT}/include
-  NO_DEFAULT_PATH
-  )
-
-list(APPEND SYCL_INCLUDE_DIR ${SYCL_INCLUDE_SYCL_DIR})
-
-find_file(
-  SYCL_LIBRARY_DIR
-  NAMES lib lib64
-  HINTS ${SYCL_ROOT}
-  NO_DEFAULT_PATH
-  )
-
-find_library(
-  SYCL_LIBRARY
-  NAMES sycl
-  HINTS ${SYCL_LIBRARY_DIR}
-  NO_DEFAULT_PATH
-)
-
-if((NOT SYCL_INCLUDE_DIR) OR (NOT SYCL_LIBRARY_DIR) OR (NOT SYCL_LIBRARY))
-  set(SYCLTOOLKIT_FOUND False)
-  set(SYCL_REASON_FAILURE "SYCL sdk is incomplete!!")
-  set(SYCL_NOT_FOUND_MESSAGE "${SYCL_REASON_FAILURE}")
-  return()
-endif()
-
 # Function to write a test case to verify SYCL features.
 
 function(SYCL_CMPLR_TEST_WRITE src)
@@ -202,6 +169,13 @@ set(SYCL_FLAGS "")
 set(SYCL_LINK_FLAGS "")
 list(APPEND SYCL_FLAGS "-fsycl")
 list(APPEND SYCL_LINK_FLAGS "-fsycl")
+if(LINUX)
+  string(REGEX MATCH "libsycl-preview.so" is_abi_neutral ${SYCL_LIBRARY})
+  if(is_abi_neutral)
+    list(APPEND SYCL_FLAGS "-fpreview-breaking-changes")
+    list(APPEND SYCL_LINK_FLAGS "-fpreview-breaking-changes")
+  endif()
+endif()
 
 set(SYCL_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${SYCL_FLAGS}")
 
@@ -249,14 +223,3 @@ endif()
 
 message(DEBUG "The SYCL compiler is ${SYCL_COMPILER}")
 message(DEBUG "The SYCL Flags are ${SYCL_FLAGS}")
-
-# Avoid module variables conflict due to calling find_package recursively
-# e.g. find_package -> add_subdirectory(entering in a sub-project) -> find_package
-# find_package_handle_standard_args(
-#   SYCLToolkit
-#   FOUND_VAR SYCLTOOLKIT_FOUND
-#   REQUIRED_VARS SYCL_INCLUDE_DIR SYCL_LIBRARY_DIR SYCL_LIBRARY SYCL_FLAGS
-#   VERSION_VAR SYCL_LANGUAGE_VERSION
-#   REASON_FAILURE_MESSAGE "${SYCL_REASON_FAILURE}")
-set(SYCLTOOLKIT_FOUND True)
-

cmake/SYCL.cmake

@@ -25,24 +25,6 @@ if(NOT SYCL_VERSION)
   return()
 endif()
 
-find_library(SYCL_LIBRARIES sycl HINTS ${SYCL_LIBRARY_DIR})
-# On Windows, currently there's no sycl.lib. Only sycl7.lib with version suffix,
-# where the current version of the SYCL runtime is 7.
-# Until oneAPI adds support to sycl.lib without the version suffix,
-# sycl_runtime_version needs to be hardcoded and uplifted when SYCL runtime version uplifts.
-# TODO: remove this when sycl.lib is supported on Windows
-if(WIN32)
-  set(sycl_runtime_version 7)
-  find_library(
-    SYCL_LIBRARIES
-    NAMES "sycl${sycl_runtime_version}"
-    HINTS ${SYCL_LIBRARY_DIR}
-  )
-  if(SYCL_LIBRARIES STREQUAL "SYCL_LIBRARIES-NOTFOUND")
-    message(FATAL_ERROR "Cannot find a SYCL library on Windows")
-  endif()
-endif()
-
 set(SYCL_COMPILER_VERSION)
 file(READ ${SYCL_VERSION} version_contents)
 string(REGEX MATCHALL "__SYCL_COMPILER_VERSION +[0-9]+" VERSION_LINE "${version_contents}")

src/ATen/CMakeLists.txt

@@ -1,6 +1,6 @@
 # ATen XPU sources
 
-file(GLOB xpu_cpp "xpu/*.cpp", "native/xpu/*.cpp", "native/sparse/*.cpp")
+file(GLOB xpu_cpp "xpu/*.cpp" "native/xpu/*.cpp" "native/sparse/*.cpp")
 file(GLOB xpu_sycl "native/xpu/sycl/*.cpp")
 
 list(APPEND ATen_XPU_CPP_SRCS ${xpu_cpp})

src/ATen/native/xpu/sycl/AmpKernels.cpp

@@ -102,9 +102,9 @@ void amp_foreach_non_finite_check_and_unscale_kernel(
 }
 
 struct AmpUpdateScaleKernelFunctor {
-  void operator()(sycl::item<1> item) const {
+  void operator()(sycl::nd_item<1> item) const {
     // There is only single item/task scheduled.
-    if (item.get_linear_id() != 0)
+    if (item.get_global_linear_id() != 0)
       return;
 
     if (*found_inf_) {

src/CMakeLists.txt

@@ -82,7 +82,7 @@ foreach(lib ${TORCH_XPU_OPS_LIBRARIES})
   target_include_directories(${lib} PUBLIC ${ATen_XPU_INCLUDE_DIRS})
   target_include_directories(${lib} PUBLIC ${SYCL_INCLUDE_DIR})
 
-  target_link_libraries(${lib} PUBLIC ${SYCL_LIBRARIES})
+  target_link_libraries(${lib} PUBLIC ${SYCL_LIBRARY})
 endforeach()
 
 include(${TORCH_XPU_OPS_ROOT}/cmake/ClangFormat.cmake)

test/sycl/CMakeLists.txt

@@ -42,7 +42,7 @@ add_dependencies(test_sycl_build_archive sycl_simple_kernel_test)
 # Instead, we use explicit linkage option '--whole-archive', which is required
 # by linkage of device object modules archived in the static library. Then
 # explicit linkage configuration of SYCL runtime library is required.
-target_link_libraries(test_sycl_build_archive ${SYCL_LIBRARIES})
+target_link_libraries(test_sycl_build_archive ${SYCL_LIBRARY})
 
 if(INSTALL_TEST)
   install(TARGETS test_sycl_build_archive DESTINATION bin)