Remove BUILD_SPLIT_KERNEL_LIB flag (#2208)

`BUILD_SPLIT_KERNEL_LIB` looks like workaround, which is no longer
needed in new compiler versions. From release notes

> The compiler team introduced device image compression in version
2025.0.1, and this feature is now enabled in oneMKL 2025.2 builds. It
facilitates the reduction in size of SYCL libraries with large kernels
by approximately 12% to 40% for both static and dynamic libraries on
Linux, as well as dynamic libraries on Windows.

Also this flag can't be used for Debug/RelWithDefInfo builds, as for
these configs `BUILD_SEPARATE_OPS` takes precedence
```CMake
if(CMAKE_BUILD_TYPE MATCHES "(Debug|RelWithDebInfo)")
  set(BUILD_SEPARATE_OPS TRUE)
endif()

...

if(BUILD_SEPARATE_OPS)
  ...
elseif(BUILD_SPLIT_KERNEL_LIB OR __INTEL_LLVM_COMPILER LESS 20250004 OR ICX_DATE LESS 20241205)
  ...
else()
  ...
endif()
```
Continuation of #2204

Author: Silv3S

src/BuildOnLinux.cmake

@@ -36,87 +36,6 @@ if(BUILD_SEPARATE_OPS)
     # Decouple with PyTorch cmake definition.
     install(TARGETS ${sycl_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
   endforeach()
-# Working with the compilers which don't support device code compression, we have to split kernels
-# into multiple libraries to meet the bin size limitation.
-elseif(BUILD_SPLIT_KERNEL_LIB OR __INTEL_LLVM_COMPILER LESS 20250004 OR ICX_DATE LESS 20241205)
-  setup_common_libraries()
-  # Split SYCL kernels into 4 libraries as categories 1) Unary+Binary 2) Reduce 3) Foreach 4) Others.
-  set(ATen_XPU_SYCL_UNARY_BINARY_SRCS)
-  set(ATen_XPU_SYCL_REDUCE_SRCS)
-  set(ATen_XPU_SYCL_FOREACH_SRCS)
-  set(ATen_XPU_SYCL_OTHERS_SRCS)
-
-  foreach(sycl_src ${ATen_XPU_SYCL_SRCS})
-    string(REGEX MATCH "Binary" IS_BINARY ${sycl_src})
-    string(REGEX MATCH "Unary" IS_UNARY ${sycl_src})
-    string(REGEX MATCH "Pow" IS_POW ${sycl_src})
-    string(REGEX MATCH "Copy" IS_COPY ${sycl_src})
-    string(REGEX MATCH "Reduce" IS_REDUCE ${sycl_src})
-    string(REGEX MATCH "Activation" IS_ACTIVATION ${sycl_src})
-    string(REGEX MATCH "Foreach" IS_FOREACH ${sycl_src})
-
-    if(NOT IS_FOREACH STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_FOREACH_SRCS ${sycl_src})
-    elseif(NOT IS_REDUCE STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_REDUCE_SRCS ${sycl_src})
-    elseif(NOT IS_UNARY STREQUAL "" OR NOT IS_BINARY STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_UNARY_BINARY_SRCS ${sycl_src})
-    elseif(NOT IS_COPY STREQUAL "" OR NOT IS_POW STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_UNARY_BINARY_SRCS ${sycl_src})
-    elseif(NOT IS_ACTIVATION STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_UNARY_BINARY_SRCS ${sycl_src})
-    else()
-      list(APPEND ATen_XPU_SYCL_OTHERS_SRCS ${sycl_src})
-    endif()
-  endforeach()
-
-  # Unary binary kernel lib
-  set(sycl_unary_binary_lib torch_xpu_ops_sycl_unary_binary_kernels)
-  sycl_add_library(
-    ${sycl_unary_binary_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_UNARY_BINARY_SRCS})
-  target_link_libraries(torch_xpu_ops PUBLIC ${sycl_unary_binary_lib})
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_unary_binary_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_unary_binary_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Reduce kernel lib
-  set(sycl_reduce_lib torch_xpu_ops_sycl_reduce_kernels)
-  sycl_add_library(
-    ${sycl_reduce_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_REDUCE_SRCS})
-  target_link_libraries(torch_xpu_ops PUBLIC ${sycl_reduce_lib})
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_reduce_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_reduce_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Foreach kernel lib
-  set(sycl_foreach_lib torch_xpu_ops_sycl_foreach_kernels)
-  sycl_add_library(
-    ${sycl_foreach_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_FOREACH_SRCS})
-  target_link_libraries(torch_xpu_ops PUBLIC ${sycl_foreach_lib})
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_foreach_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_foreach_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Other kernel lib
-  set(sycl_lib torch_xpu_ops_sycl_kernels)
-  sycl_add_library(
-    ${sycl_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_OTHERS_SRCS})
-  target_link_libraries(torch_xpu_ops PUBLIC ${sycl_lib})
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
 else()
   sycl_add_library(
     torch_xpu_ops

src/BuildOnWindows.cmake

@@ -39,206 +39,6 @@ if(BUILD_SEPARATE_OPS)
     # Decouple with PyTorch cmake definition.
     install(TARGETS ${sycl_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
   endforeach()
-  list(APPEND TORCH_XPU_OPS_LIBRARIES torch_xpu_ops)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES torch_xpu_ops_aten)
-# Working with the compilers which don't support device code compression, we have to split kernels
-# into multiple libraries to meet the bin size limitation.
-elseif(BUILD_SPLIT_KERNEL_LIB OR __INTEL_LLVM_COMPILER LESS 20250004 OR ICX_DATE LESS 20241205)
-  setup_common_libraries()
-  # Split SYCL kernels into 2 libraries as categories 1) Unary+Binary 2) Others.
-  set(ATen_XPU_SYCL_BINARY_SRCS)
-  set(ATen_XPU_SYCL_UNARY_SRCS)
-  set(ATen_XPU_SYCL_REDUCE_SRCS)
-  set(ATen_XPU_SYCL_ACTIVATION_SRCS)
-  set(ATen_XPU_SYCL_FOREACH_SRCS)
-  set(ATen_XPU_SYCL_TENSOR_SRCS)
-  set(ATen_XPU_SYCL_NORM_LOSS_SRCS)
-  set(ATen_XPU_SYCL_POLY_SRCS)
-  set(ATen_XPU_SYCL_DISTRIBUTION_SRCS)
-  set(ATen_XPU_SYCL_OTHERS_SRCS)
-  foreach(sycl_src ${ATen_XPU_SYCL_SRCS})
-    string(REGEX MATCH "Binary" IS_BINARY ${sycl_src})
-    string(REGEX MATCH "Unary" IS_UNARY ${sycl_src})
-    # Resolve cyclic dependences between
-    # torch_xpu_ops_sycl_unary_binary_kernels.dll and
-    # torch_xpu_ops_sycl_kernels.dll. Move definition and invoke of kernels
-    # into a same kernel library. Here we move elementwise kernel pow and copy
-    # into torch_xpu_ops_sycl_unary_binary_kernels.dll.
-    string(REGEX MATCH "Pow" IS_POW ${sycl_src})
-    string(REGEX MATCH "Copy" IS_COPY ${sycl_src})
-    string(REGEX MATCH "Activation" IS_ACTIVATION ${sycl_src})
-    string(REGEX MATCH "Foreach" IS_FOREACH ${sycl_src})
-    string(REGEX MATCH "Reduce" IS_REDUCE ${sycl_src})
-    string(REGEX MATCH "Tensor" IS_TENSOR ${sycl_src})
-    string(REGEX MATCH "Norm" IS_NORM ${sycl_src})
-    string(REGEX MATCH "Loss" IS_LOSS ${sycl_src})
-    string(REGEX MATCH "Polynomial" IS_POLY ${sycl_src})
-    #Move resize kernel to Norm and Loss lib, to resolve symbol.
-    string(REGEX MATCH "Resize" IS_RESIZE ${sycl_src})
-    string(REGEX MATCH "Distribution" IS_DISTRIBUTION ${sycl_src})
-
-    if(NOT IS_FOREACH STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_FOREACH_SRCS ${sycl_src})
-    elseif(NOT IS_BINARY STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_BINARY_SRCS ${sycl_src})
-    elseif(NOT IS_UNARY STREQUAL "" OR NOT IS_COPY STREQUAL "" OR NOT IS_POW STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_UNARY_SRCS ${sycl_src})
-    elseif(NOT IS_REDUCE STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_REDUCE_SRCS ${sycl_src})
-    elseif(NOT IS_ACTIVATION STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_ACTIVATION_SRCS ${sycl_src})
-    elseif(NOT IS_TENSOR STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_TENSOR_SRCS ${sycl_src})
-    elseif(NOT IS_DISTRIBUTION STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_DISTRIBUTION_SRCS ${sycl_src})
-    elseif(NOT IS_NORM STREQUAL "" OR NOT IS_LOSS STREQUAL "" OR NOT IS_RESIZE STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_NORM_LOSS_SRCS ${sycl_src})
-    elseif(NOT IS_POLY STREQUAL "")
-      list(APPEND ATen_XPU_SYCL_POLY_SRCS ${sycl_src})
-    else()
-      list(APPEND ATen_XPU_SYCL_OTHERS_SRCS ${sycl_src})
-    endif()
-  endforeach()
-  # Binary kernel lib
-  set(sycl_binary_lib torch_xpu_ops_sycl_binary_kernels)
-  sycl_add_library(
-    ${sycl_binary_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_BINARY_SRCS})
-  target_compile_definitions(${sycl_binary_lib} PRIVATE TORCH_XPU_BUILD_MAIN_LIB)
-  target_link_libraries(torch_xpu_ops_aten PUBLIC ${sycl_binary_lib})
-  target_link_libraries(${sycl_binary_lib} PUBLIC torch_xpu)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_binary_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_binary_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Unary kernel lib
-  set(sycl_unary_lib torch_xpu_ops_sycl_unary_kernels)
-  sycl_add_library(
-    ${sycl_unary_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_UNARY_SRCS})
-  target_compile_definitions(${sycl_unary_lib} PRIVATE TORCH_XPU_BUILD_MAIN_LIB)
-  target_link_libraries(torch_xpu_ops_aten PUBLIC ${sycl_unary_lib})
-  target_link_libraries(${sycl_unary_lib} PUBLIC torch_xpu)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_unary_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_unary_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Reduce kernel lib
-  set(sycl_reduce_lib torch_xpu_ops_sycl_reduce_kernels)
-  sycl_add_library(
-    ${sycl_reduce_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_REDUCE_SRCS})
-  target_compile_definitions(${sycl_reduce_lib} PRIVATE TORCH_XPU_BUILD_MAIN_LIB)
-  target_link_libraries(torch_xpu_ops_aten PUBLIC ${sycl_reduce_lib})
-  target_link_libraries(${sycl_reduce_lib} PUBLIC torch_xpu)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_reduce_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_reduce_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Activation kernel lib
-  set(sycl_activation_lib torch_xpu_ops_sycl_activation_kernels)
-  sycl_add_library(
-    ${sycl_activation_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_ACTIVATION_SRCS})
-  target_compile_definitions(${sycl_activation_lib} PRIVATE TORCH_XPU_BUILD_MAIN_LIB)
-  target_link_libraries(torch_xpu_ops_aten PUBLIC ${sycl_activation_lib})
-  target_link_libraries(${sycl_activation_lib} PUBLIC torch_xpu)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_activation_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_activation_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Foreach kernel lib
-  set(sycl_foreach_lib torch_xpu_ops_sycl_foreach_kernels)
-  sycl_add_library(
-    ${sycl_foreach_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_FOREACH_SRCS})
-  target_compile_definitions(${sycl_foreach_lib} PRIVATE TORCH_XPU_BUILD_MAIN_LIB)
-  target_link_libraries(torch_xpu_ops_aten PUBLIC ${sycl_foreach_lib})
-  target_link_libraries(${sycl_foreach_lib} PUBLIC torch_xpu)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_foreach_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_foreach_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Tensor kernel lib
-  set(sycl_tensor_lib torch_xpu_ops_sycl_tensor_kernels)
-  sycl_add_library(
-    ${sycl_tensor_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_TENSOR_SRCS})
-  target_compile_definitions(${sycl_tensor_lib} PRIVATE TORCH_XPU_BUILD_MAIN_LIB)
-  target_link_libraries(torch_xpu_ops_aten PUBLIC ${sycl_tensor_lib})
-  target_link_libraries(${sycl_tensor_lib} PUBLIC torch_xpu)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_tensor_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_tensor_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Norm and Loss kernel lib
-  set(sycl_norm_loss_lib torch_xpu_ops_sycl_norm_loss_kernels)
-  sycl_add_library(
-    ${sycl_norm_loss_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_NORM_LOSS_SRCS})
-  target_compile_definitions(${sycl_norm_loss_lib} PRIVATE TORCH_XPU_BUILD_MAIN_LIB)
-  target_link_libraries(torch_xpu_ops_aten PUBLIC ${sycl_norm_loss_lib})
-  target_link_libraries(${sycl_norm_loss_lib} PUBLIC torch_xpu)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_norm_loss_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_norm_loss_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Polynomial kernel lib
-  set(sycl_poly_lib torch_xpu_ops_sycl_poly_kernels)
-  sycl_add_library(
-    ${sycl_poly_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_POLY_SRCS})
-  target_compile_definitions(${sycl_poly_lib} PRIVATE TORCH_XPU_BUILD_MAIN_LIB)
-  target_link_libraries(torch_xpu_ops_aten PUBLIC ${sycl_poly_lib})
-  target_link_libraries(${sycl_poly_lib} PUBLIC torch_xpu)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_poly_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_poly_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Distribution kernel lib
-  set(sycl_dist_lib torch_xpu_ops_sycl_dist_kernels)
-  sycl_add_library(
-    ${sycl_dist_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_DISTRIBUTION_SRCS})
-  target_compile_definitions(${sycl_dist_lib} PRIVATE TORCH_XPU_BUILD_MAIN_LIB)
-  target_link_libraries(torch_xpu_ops_aten PUBLIC ${sycl_dist_lib})
-  target_link_libraries(${sycl_dist_lib} PUBLIC torch_xpu)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_dist_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_dist_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
-  # Other kernel lib
-  set(sycl_lib torch_xpu_ops_sycl_kernels)
-  sycl_add_library(
-    ${sycl_lib}
-    SHARED
-    SYCL_SOURCES ${ATen_XPU_SYCL_OTHERS_SRCS})
-  target_compile_definitions(${sycl_lib} PRIVATE TORCH_XPU_BUILD_MAIN_LIB)
-  target_link_libraries(torch_xpu_ops_aten PUBLIC ${sycl_lib})
-  target_link_libraries(${sycl_lib} PUBLIC torch_xpu)
-  list(APPEND TORCH_XPU_OPS_LIBRARIES ${sycl_lib})
-
-  # Decouple with PyTorch cmake definition.
-  install(TARGETS ${sycl_lib} DESTINATION "${TORCH_INSTALL_LIB_DIR}")
-
   list(APPEND TORCH_XPU_OPS_LIBRARIES torch_xpu_ops)
   list(APPEND TORCH_XPU_OPS_LIBRARIES torch_xpu_ops_aten)
 else()