[Math] Migrate completely aways from VecCore

Author: guitargeek

.ci/copy_headers.sh

@@ -6,7 +6,7 @@ set -ex
 mkdir ../build
 cd ../build
 cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=ON -Dall=On -Dtesting=On -Dx11=Off -Dalien=Off \
-      -Dcuda=Off -Dtmva-gpu=Off -Dveccore=Off ../root
+      -Dcuda=Off -Dtmva-gpu=Off ../root
 # We need to prebuild a minimal set of targets which are responsible for header copy
 # or generation.
 make -j4 move_headers intrinsics_gen clang-tablegen-targets ClangDriverOptions \

.github/workflows/root-ci-config/buildconfig/global.txt

@@ -25,7 +25,6 @@ builtin_pcre=OFF
 builtin_tbb=OFF
 builtin_unuran=OFF
 builtin_vdt=OFF
-builtin_veccore=OFF
 builtin_xrootd=OFF
 builtin_xxhash=OFF
 builtin_zeromq=ON
@@ -97,7 +96,6 @@ unfold=ON
 unuran=ON
 uring=OFF
 vdt=ON
-veccore=OFF
 vecgeom=OFF
 webgui=ON
 win_broken_tests=OFF

.github/workflows/root-ci-config/buildconfig/mac-beta.txt

@@ -17,7 +17,6 @@ builtin_pcre=ON
 builtin_tbb=ON
 builtin_unuran=ON
 builtin_vdt=ON
-builtin_veccore=ON
 builtin_xrootd=ON
 builtin_xxhash=ON
 builtin_zeromq=ON

.github/workflows/root-ci-config/buildconfig/mac14.txt

@@ -19,7 +19,6 @@ builtin_pcre=ON
 builtin_tbb=ON
 builtin_unuran=ON
 builtin_vdt=ON
-builtin_veccore=ON
 builtin_xrootd=ON
 builtin_xxhash=ON
 builtin_zeromq=ON

.github/workflows/root-ci-config/buildconfig/mac15.txt

@@ -16,7 +16,6 @@ builtin_pcre=ON
 builtin_tbb=ON
 builtin_unuran=ON
 builtin_vdt=ON
-builtin_veccore=ON
 builtin_xrootd=ON
 builtin_xxhash=ON
 builtin_zeromq=ON

.github/workflows/root-ci-config/buildconfig/mac26.txt

@@ -17,7 +17,6 @@ builtin_pcre=ON
 builtin_tbb=ON
 builtin_unuran=ON
 builtin_vdt=ON
-builtin_veccore=ON
 builtin_xrootd=ON
 builtin_xxhash=ON
 builtin_zeromq=ON

cmake/modules/RootBuildOptions.cmake

@@ -108,7 +108,6 @@ ROOT_BUILD_OPTION(builtin_png OFF "Build bundled copy of libpng")
 ROOT_BUILD_OPTION(builtin_tbb OFF "Build TBB internally (requires network)")
 ROOT_BUILD_OPTION(builtin_unuran OFF "Build bundled copy of unuran")
 ROOT_BUILD_OPTION(builtin_vdt OFF "Build VDT internally (requires network)")
-ROOT_BUILD_OPTION(builtin_veccore OFF "Build VecCore internally (requires network)")
 ROOT_BUILD_OPTION(builtin_xrootd OFF "Build XRootD internally (requires network)")
 ROOT_BUILD_OPTION(builtin_xxhash OFF "Build bundled copy of xxHash")
 ROOT_BUILD_OPTION(builtin_zeromq OFF "Build ZeroMQ internally (requires network)")
@@ -180,7 +179,6 @@ ROOT_BUILD_OPTION(unuran OFF "Enable support for UNURAN (package for generating
 ROOT_BUILD_OPTION(uring OFF "Enable support for io_uring (requires liburing and Linux kernel >= 5.1)")
 ROOT_BUILD_OPTION(use_gsl_cblas ON "Use the CBLAS library from GSL instead of finding a more optimized BLAS library automatically with FindBLAS (the GSL CBLAS is less performant but more portable)")
 ROOT_BUILD_OPTION(vdt ON "Enable support for VDT (fast and vectorisable mathematical functions)")
-ROOT_BUILD_OPTION(veccore OFF "Enable support for VecCore SIMD abstraction library")
 ROOT_BUILD_OPTION(vecgeom OFF "Enable support for VecGeom vectorized geometry library")
 ROOT_BUILD_OPTION(webgui ON "Build Web-based UI components of ROOT")
 ROOT_BUILD_OPTION(win_broken_tests OFF "Enable broken tests on Windows")
@@ -252,7 +250,6 @@ if(all)
  set(tmva-rmva_defvalue ON)
  set(unuran_defvalue ON)
  set(vdt_defvalue ON)
- set(veccore_defvalue ON)
  set(vecgeom_defvalue ON)
  set(x11_defvalue ON)
  set(xml_defvalue ON)
@@ -293,7 +290,6 @@ if(builtin_all)
   set(builtin_tbb_defvalue ON)
 #  set(builtin_unuran_defvalue ON) (GPL)
   set(builtin_vdt_defvalue ON)
-  set(builtin_veccore_defvalue ON)
   set(builtin_xrootd_defvalue ON)
   set(builtin_xxhash_defvalue ON)
   set(builtin_zeromq_defvalue ON)
@@ -411,35 +407,14 @@ if(DEFINED rpath)
       "") # empty line at the end to make the deprecation message more visible
 endif()
 
-foreach(opt vc builtin_vc)
+foreach(opt vc builtin_vc veccore builtin_veccore)
   if(${opt})
     message(DEPRECATION ">>> Option '${opt}' is deprecated and ignored."
-        "ROOT now uses std::simd for the vectorized TFormula and TMath classes when available (Clang or GCC >= 9)."
+        "ROOT now uses std::experimental::simd for the vectorized TFormula and TMath classes when available (on Linux when compiling with C++20 or higher)."
         "Using this option will result in configuration errors in ROOT 6.42.")
   endif()
 endforeach()
 
-foreach(opt veccore builtin_veccore)
-  # Disable VecCore if we don't support it for a given platform.
-  # We try to give clear explanations here in all distinct cases.
-  if(${opt})
-    if(WIN32)
-      message(WARNING "ROOT option '${opt}' will be disabled. Using VecCore on Windows is not supported by ROOT.")
-      set(${opt} OFF CACHE BOOL "Disabled because VecCore is not supported on Windows." FORCE)
-    elseif(APPLE AND CMAKE_SYSTEM_PROCESSOR STREQUAL "x86_64")
-      message(WARNING "ROOT option '${opt}' will be disabled. We don't support using VecCore on Apple with Intel hardware anymore.")
-      set(${opt} OFF CACHE BOOL "Disabled because VecCore is not supported on Apple with Intel hardware." FORCE)
-    elseif(APPLE)
-      message(WARNING "ROOT option '${opt}' will be disabled. We don't support using VecCore on Apple silicon, as std::simd is not available for Apple Clang and the old Vc backend also didn't support Apple silicon anyway.")
-      set(${opt} OFF CACHE BOOL "Disabled because VecCore is not supported on Apple silicon." FORCE)
-    elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU"
-           AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 9)
-      message(WARNING "ROOT option '${opt}' will be disabled. GCC versions older than 9 do not provide std::simd, and the Vc backend of VecCore is not supported anymore by ROOT.")
-      set(${opt} OFF CACHE BOOL "Disabled because VecCore is not supported on GCC < 9." FORCE)
-    endif()
-  endif()
-endforeach()
-
 foreach(opt minuit2_mpi)
   if(${opt})
       message(WARNING "The option '${opt}' can only be used to minimise thread-safe functions in Minuit2. It cannot be used for Histogram/Graph fitting and for RooFit. If you want to use Minuit2 with MPI support, it is better to build Minuit2 as a standalone library.")

cmake/modules/RootConfiguration.cmake

@@ -370,10 +370,11 @@ if(vdt)
 else()
   set(hasvdt undef)
 endif()
-if(veccore)
-  set(hasveccore define)
+# Assume std::experimental::simd is available on Linux if we build with C++20 on Linux
+if(WIN32 OR APPLE OR CMAKE_CXX_STANDARD LESS 20)
+  set(hasstdsimd undef)
 else()
-  set(hasveccore undef)
+  set(hasstdsimd define)
 endif()
 if(dataframe)
   set(hasdataframe define)

cmake/modules/SearchInstalledSoftware.cmake

@@ -1365,88 +1365,6 @@ if(builtin_tbb)
   set(TBB_TARGET TBB)
 endif()
 
-#---Check for VecCore--------------------------------------------------------------------
-if(builtin_veccore)
-  unset(VecCore_FOUND)
-  unset(VecCore_FOUND CACHE)
-  set(veccore ON CACHE BOOL "Enabled because builtin_veccore requested (${veccore_description})" FORCE)
-elseif(veccore)
-  if(fail-on-missing)
-    find_package(VecCore 0.4.2 CONFIG QUIET REQUIRED COMPONENTS ${VecCore_COMPONENTS})
-  else()
-    find_package(VecCore 0.4.2 CONFIG QUIET COMPONENTS ${VecCore_COMPONENTS})
-    if(NOT VecCore_FOUND)
-      ROOT_CHECK_CONNECTION("veccore=OFF")
-      if(NO_CONNECTION)
-        message(STATUS "VecCore not found and no internet connection, disabling the 'veccore' option")
-        set(veccore OFF CACHE BOOL "Disabled because not found and No internet connection" FORCE)
-      else()
-        message(STATUS "VecCore not found, switching on 'builtin_veccore' option.")
-        set(builtin_veccore ON CACHE BOOL "Enabled because veccore requested and not found externally (${builtin_veccore_description})" FORCE)
-      endif()
-    endif()
-  endif()
-  if(VecCore_FOUND)
-      set_property(DIRECTORY APPEND PROPERTY INCLUDE_DIRECTORIES ${VecCore_INCLUDE_DIRS})
-  endif()
-endif()
-
-if(builtin_veccore)
-  ROOT_CHECK_CONNECTION_AND_DISABLE_OPTION("builtin_veccore")
-endif()
-
-if(builtin_veccore)
-  set(VecCore_VERSION "0.8.2")
-  set(VecCore_PROJECT "VecCore-${VecCore_VERSION}")
-  set(VecCore_SRC_URI "${lcgpackages}/${VecCore_PROJECT}.tar.gz")
-  set(VecCore_DESTDIR "${CMAKE_BINARY_DIR}/externals")
-  set(VecCore_ROOTDIR "${VecCore_DESTDIR}/${CMAKE_INSTALL_PREFIX}")
-
-  ExternalProject_Add(VECCORE
-    URL     ${VecCore_SRC_URI}
-    URL_HASH SHA256=1268bca92acf00acd9775f1e79a2da7b1d902733d17e283e0dd5e02c41ac9666
-    BUILD_IN_SOURCE 0
-    LOG_DOWNLOAD 1 LOG_CONFIGURE 1 LOG_BUILD 1 LOG_INSTALL 1 LOG_OUTPUT_ON_FAILURE 1
-    CMAKE_ARGS -G ${CMAKE_GENERATOR}
-               -DBUILD_TESTING=OFF
-               -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}
-               -DCMAKE_C_COMPILER=${CMAKE_C_COMPILER}
-               -DCMAKE_C_FLAGS=${CMAKE_C_FLAGS}
-               -DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}
-               -DCMAKE_CXX_FLAGS=${ROOT_EXTERNAL_CXX_FLAGS}
-               -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}
-    INSTALL_COMMAND env DESTDIR=${VecCore_DESTDIR} ${CMAKE_COMMAND} --build . --target install
-    TIMEOUT 600
-  )
-
-  set(VECCORE_TARGET VecCore)
-  set(VecCore_LIBRARIES VecCore)
-  list(APPEND VecCore_INCLUDE_DIRS ${VecCore_ROOTDIR}/include)
-
-  add_library(VecCore INTERFACE)
-  target_include_directories(VecCore SYSTEM INTERFACE $<BUILD_INTERFACE:${VecCore_ROOTDIR}/include>)
-  add_dependencies(VecCore VECCORE)
-
-  find_package_handle_standard_args(VecCore
-    FOUND_VAR VecCore_FOUND
-    REQUIRED_VARS VecCore_INCLUDE_DIRS VecCore_LIBRARIES
-    VERSION_VAR VecCore_VERSION)
-
-  # FIXME: This is a workaround to let ROOT find the headers at runtime if
-  # they are in the build directory. This is necessary until we decide how to
-  # treat externals with headers used by ROOT
-  if(NOT EXISTS ${CMAKE_BINARY_DIR}/include/VecCore)
-    if (NOT EXISTS ${CMAKE_BINARY_DIR}/include)
-      execute_process(COMMAND ${CMAKE_COMMAND} -E make_directory ${CMAKE_BINARY_DIR}/include)
-    endif()
-    execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink
-      ${VecCore_ROOTDIR}/include/VecCore ${CMAKE_BINARY_DIR}/include/VecCore)
-  endif()
-  # end of workaround
-
-  install(DIRECTORY ${VecCore_ROOTDIR}/ DESTINATION ".")
-endif()
-
 if(builtin_vdt)
   ROOT_CHECK_CONNECTION_AND_DISABLE_OPTION("builtin_vdt")
 endif()
@@ -1520,12 +1438,6 @@ endif()
 if (vecgeom)
   message(STATUS "Looking for VecGeom")
   find_package(VecGeom 1.2 CONFIG)
-  if(builtin_veccore)
-    message(WARNING "ROOT must be built against the VecCore installation that was used to build VecGeom; builtin_veccore cannot be used. Option VecGeom will be disabled.")
-    set(vecgeom OFF CACHE BOOL "Disabled because non-builtin VecGeom specified but its VecCore cannot be found" FORCE)
-  elseif(builtin_veccore AND fail-on-missing)
-    message(SEND_ERROR "ROOT must be built against the VecCore installation that was used to build VecGeom; builtin_veccore cannot be used. Ensure that builtin_veccore option is OFF.")
-  endif()
   if(NOT VecGeom_FOUND )
     if(fail-on-missing)
       message(SEND_ERROR "VecGeom not found. Ensure that the installation of VecGeom is in the CMAKE_PREFIX_PATH")

config/RConfigure.in

@@ -38,7 +38,7 @@
 #@hasclad@ R__HAS_CLAD    /**/
 #@hascocoa@ R__HAS_COCOA    /**/
 #@hasvdt@ R__HAS_VDT    /**/
-#@hasveccore@ R__HAS_VECCORE    /**/
+#@hasstdsimd@ R__HAS_STD_SIMD    /**/
 #@usecxxmodules@ R__USE_CXXMODULES   /**/
 #@uselibc++@ R__USE_LIBCXX    /**/
 #@has_found_attribute_always_inline@ R__HAS_ATTRIBUTE_ALWAYS_INLINE /**/