[llvm] [SYCL] Add libsycl, a SYCL RT library implementation project (PR #144372)

[Kseniya Tikhomirova via llvm-commits]

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@@ -0,0 +1,110 @@
+#===============================================================================
+# Setup Project
+#===============================================================================
+cmake_minimum_required(VERSION 3.20.0)
+
+set(LLVM_SUBPROJECT_TITLE "libsycl")
+
+set(LIBSYCL_SOURCE_DIR  ${CMAKE_CURRENT_SOURCE_DIR})
+set(LIBSYCL_BINARY_DIR  ${CMAKE_CURRENT_BINARY_DIR})
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED YES)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
+#===============================================================================
+# Setup CMake Options
+#===============================================================================
+
+option(LIBSYCL_ENABLE_WERROR "Treat all warnings as errors in the libsycl project" OFF)
+option(LIBSYCL_ENABLE_PEDANTIC "Compile with pedantic enabled." OFF)
+
+#===============================================================================
+# Configure System
+#===============================================================================
+
+set_property(GLOBAL PROPERTY USE_FOLDERS ON)
+
+set(LIBSYCL_SHARED_OUTPUT_NAME "sycl" CACHE STRING "Output name for the shared libsycl runtime library.")
+
+if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
+  set(LIBSYCL_TARGET_SUBDIR ${LLVM_DEFAULT_TARGET_TRIPLE})
+  if(LIBSYCL_LIBDIR_SUBDIR)
+    string(APPEND LIBSYCL_TARGET_SUBDIR /${LIBSYCL_LIBDIR_SUBDIR})
+  endif()
+  cmake_path(NORMAL_PATH LIBSYCL_TARGET_SUBDIR)
+  set(LIBSYCL_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LIBSYCL_TARGET_SUBDIR})
+  set(LIBSYCL_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LIBSYCL_TARGET_SUBDIR} CACHE STRING
+      "Path where built libsycl libraries should be installed.")
+  unset(LIBSYCL_TARGET_SUBDIR)
+else()
+  if(LLVM_LIBRARY_OUTPUT_INTDIR)
+    set(LIBSYCL_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
+  else()
+    set(LIBSYCL_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBSYCL_LIBDIR_SUFFIX})
+  endif()
+  set(LIBSYCL_INSTALL_LIBRARY_DIR lib${LIBSYCL_LIBDIR_SUFFIX} CACHE STRING
+      "Path where built libsycl libraries should be installed.")
+endif()
+
+set(LIBSYCL_INCLUDE_DIR include)
+set(LIBSYCL_BUILD_INCLUDE_DIR ${LLVM_BINARY_DIR}/${LIBSYCL_INCLUDE_DIR})
+set(LIBSYCL_SOURCE_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/include)
+
+set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LIBSYCL_LIBRARY_DIR})
+set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LIBSYCL_LIBRARY_DIR})
+set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${LIBSYCL_LIBRARY_DIR})
+
+set(LIBSYCL_MAJOR_VERSION 0)
+set(LIBSYCL_MINOR_VERSION 1)
+set(LIBSYCL_PATCH_VERSION 0)
+set(LIBSYCL_VERSION_STRING "${LIBSYCL_MAJOR_VERSION}.${LIBSYCL_MINOR_VERSION}.${LIBSYCL_PATCH_VERSION}")
+set(LIBSYCL_ABI_NAMESPACE "V${LIBSYCL_MAJOR_VERSION}" CACHE STRING
+    "The inline ABI namespace used by libsycl. It defaults to Vn where `n` is the current ABI version.")
+
+#===============================================================================
+# Setup build & install rules
+#===============================================================================
+
+# Generate headers
+configure_file("${LIBSYCL_SOURCE_DIR}/src/version.hpp.in" "${LIBSYCL_BUILD_INCLUDE_DIR}/sycl/version.hpp")
+
+# Install generated headers.
+install(FILES
+  "${LIBSYCL_BUILD_INCLUDE_DIR}/sycl/version.hpp"
+  DESTINATION "${LIBSYCL_INCLUDE_DIR}/sycl"
+  COMPONENT sycl-headers)
+
+# This is a workaround to detect changes (add or modify) in subtree which
+# are not detected by copy_directory command.
+file(GLOB_RECURSE HEADERS_IN_SYCL_DIR CONFIGURE_DEPENDS "${LIBSYCL_SOURCE_INCLUDE_DIR}/sycl/*")
+
+string(REPLACE "${LIBSYCL_SOURCE_INCLUDE_DIR}" "${LIBSYCL_BUILD_INCLUDE_DIR}"
+  OUT_HEADERS_IN_SYCL_DIR "${HEADERS_IN_SYCL_DIR}")
+
+# Copy SYCL headers from sources to build directory
+add_custom_target(sycl-headers
+  DEPENDS ${OUT_HEADERS_IN_SYCL_DIR})
+
+add_custom_command(
+  OUTPUT  ${OUT_HEADERS_IN_SYCL_DIR}
+  DEPENDS ${HEADERS_IN_SYCL_DIR}
+  COMMAND ${CMAKE_COMMAND} -E copy_directory ${LIBSYCL_SOURCE_INCLUDE_DIR}/sycl ${LIBSYCL_BUILD_INCLUDE_DIR}/sycl
+  COMMENT "Copying SYCL headers...")
+
+install(DIRECTORY "${LIBSYCL_SOURCE_INCLUDE_DIR}/sycl" DESTINATION ${LIBSYCL_INCLUDE_DIR} COMPONENT sycl-headers)
+
+if (WIN32)
+  set(LIBSYCL_RT_LIBS ${LIBSYCL_SHARED_OUTPUT_NAME}${LIBSYCL_MAJOR_VERSION})
+  if (MSVC)
+    list(APPEND LIBSYCL_RT_LIBS ${LIBSYCL_SHARED_OUTPUT_NAME}${LIBSYCL_MAJOR_VERSION}d)
+  endif()
----------------
KseniyaTikhomirova wrote:

MSVC provides two incompatible build variants for its CRT: release and debug.
To avoid potential issues in user code we also need to provide two kinds of SYCL Runtime Library for release and debug configurations. This part was removed from this CMakeLists.txt for initial stages. I will remove these lines also. It is redundant now.

https://github.com/llvm/llvm-project/pull/144372