CMake: 3.25+

We already use features of `FindCUDAToolkit` for nvtx3 that
are CMake 3.25+. Modernize and remove pre CMake 3.20 CUDA
logic.

Author: ax3l

CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.18)
+cmake_minimum_required(VERSION 3.25)
 
 #
 # Setting a cmake_policy to OLD is deprecated by definition and will raise a
@@ -106,9 +106,6 @@ include( AMReXOptions )
 #
 if (AMReX_CUDA)
     enable_language(CUDA)
-    if(CMAKE_VERSION VERSION_LESS 3.20)
-        include(AMReX_SetupCUDA)
-    endif()
 endif ()
 
 #

Docs/sphinx_documentation/source/GPU.rst

@@ -323,8 +323,7 @@ the following code into the appropriate CMakeLists.txt file:
 
 
 If instead of using an external installation of AMReX you prefer to include AMReX as a subproject
-in your CMake setup, we strongly encourage you to use the ``AMReX_SetupCUDA`` module as shown below
-if the CMake version is less than 3.20:
+in your CMake setup (i.e., build AMReX on the fly), do this:
 
 .. highlight:: console
 
@@ -333,12 +332,7 @@ if the CMake version is less than 3.20:
    # Enable CUDA in your CMake project
    enable_language(CUDA)
 
-   # Include the AMReX-provided CUDA setup module -- OBSOLETE with CMake >= 3.20
-   if(CMAKE_VERSION VERSION_LESS 3.20)
-       include(AMReX_SetupCUDA)
-   endif()
-
-   # Include AMReX source directory ONLY AFTER the two steps above
+   # Include AMReX source directory ONLY AFTER enable_language
    add_subdirectory(/path/to/amrex/source/dir)
 
 

Tests/CMakeTestInstall/CMakeLists.txt

@@ -3,7 +3,7 @@
 # building and running the code
 # in Tests/Amr/Advection_AmrCore/
 #
-cmake_minimum_required(VERSION 3.18)
+cmake_minimum_required(VERSION 3.25)
 
 project(amrex-test-install)
 

Tests/SpackSmokeTest/CMakeLists.txt

@@ -6,7 +6,7 @@
 # against a currently installed version of AMReX. The resulting
 # executable can then be ran to test functionality.
 
-cmake_minimum_required(VERSION 3.18)
+cmake_minimum_required(VERSION 3.25)
 
 project(amrex-test-install)
 
@@ -26,9 +26,6 @@ if (AMReX_GPU_BACKEND STREQUAL "CUDA")
     find_package(AMReX REQUIRED CUDA)
 
 elseif(AMReX_GPU_BACKEND STREQUAL "HIP")
-    if(CMAKE_VERSION VERSION_LESS 3.20)
-        message(FATAL_ERROR "HIP requires CMake version 3.20 or newer")
-    endif()
     find_package(AMReX REQUIRED HIP)
     find_package(rocrand REQUIRED CONFIG)
     find_package(rocprim REQUIRED CONFIG)

Tools/CMake/AMReXConfig.cmake.in

@@ -256,11 +256,7 @@ endif ()
 #
 # AMReX 21.06+ supports CUDA_ARCHITECTURES
 if (@AMReX_CUDA@)
-    if (CMAKE_VERSION VERSION_LESS 3.20)
-        include(AMReX_SetupCUDA)
-    else ()
-        find_dependency(CUDAToolkit REQUIRED)
-    endif ()
+    find_dependency(CUDAToolkit REQUIRED)
 endif ()
 
 # CMake targets
@@ -275,7 +271,7 @@ if (NOT TARGET AMReX::amrex)  # protection in case of multiple inclusions
 endif()
 
 # More Modern CUDA CMake
-if (@CMAKE_VERSION@ VERSION_GREATER_EQUAL 3.20 AND @AMReX_CUDA@)
+if (@AMReX_CUDA@)
     foreach(D IN LISTS AMReX_SPACEDIM)
         # CUDA architectures amrex was built for -- should we make
         set(AMREX_CUDA_ARCHS @AMREX_CUDA_ARCHS@ CACHE INTERNAL "CUDA archs AMReX is built for")

Tools/CMake/AMReXFlagsTargets.cmake

@@ -25,42 +25,21 @@ include_guard(GLOBAL)
 #     <lang> = cxx,fortran,cuda
 #     <id>   = gnu,intel,pgi,cray,clang,appleclang,crayclang,ibmclang,intelllvm,msvc,nvidia,nvhpc,xlclang
 #
-if (CMAKE_VERSION VERSION_LESS 3.20)
-   foreach (_language CXX Fortran CUDA )
-      set(_comp_lang   "$<COMPILE_LANGUAGE:${_language}>")
-      string(TOLOWER "${_language}" _lang)
-
-      foreach (_comp GNU Intel PGI Cray Clang AppleClang CrayClang IBMClang IntelLLVM MSVC NVIDIA NVHPC XLClang )
-         string(TOLOWER "${_comp}" _id)
-         # Define variables
-         set(_comp_id              "$<${_language}_COMPILER_ID:${_comp}>")
-         set(_${_lang}_${_id}      "$<AND:${_comp_lang},${_comp_id}>")
-         set(_${_lang}_${_id}_dbg  "$<AND:${_comp_lang},${_comp_id},$<CONFIG:Debug>>")
-         set(_${_lang}_${_id}_rel  "$<AND:${_comp_lang},${_comp_id},$<CONFIG:Release>>")
-         set(_${_lang}_${_id}_rwdbg "$<AND:${_comp_lang},${_comp_id},$<CONFIG:RelWithDebInfo>>")
-         unset(_comp_id)
-      endforeach ()
-
-      unset(_comp_lang)
-      unset(_lang)
-   endforeach ()
-else ()
-   foreach (_language CXX Fortran CUDA )
-      string(TOLOWER "${_language}" _lang)
-
-      foreach (_comp GNU Intel PGI Cray Clang AppleClang CrayClang IBMClang IntelLLVM MSVC NVIDIA NVHPC XLClang )
-         string(TOLOWER "${_comp}" _id)
-         # Define variables
-         set(_${_lang}_${_id}      "$<COMPILE_LANG_AND_ID:${_language},${_comp}>")
-         set(_${_lang}_${_id}_dbg  "$<AND:${_${_lang}_${_id}},$<CONFIG:Debug>>")
-         set(_${_lang}_${_id}_rel  "$<AND:${_${_lang}_${_id}},$<CONFIG:Release>>")
-         set(_${_lang}_${_id}_rwdbg "$<AND:${_${_lang}_${_id}},$<CONFIG:RelWithDebInfo>>")
-         unset(_id)
-      endforeach ()
-
-      unset(_lang)
-   endforeach ()
-endif ()
+foreach (_language CXX Fortran CUDA )
+  string(TOLOWER "${_language}" _lang)
+
+  foreach (_comp GNU Intel PGI Cray Clang AppleClang CrayClang IBMClang IntelLLVM MSVC NVIDIA NVHPC XLClang )
+     string(TOLOWER "${_comp}" _id)
+     # Define variables
+     set(_${_lang}_${_id}      "$<COMPILE_LANG_AND_ID:${_language},${_comp}>")
+     set(_${_lang}_${_id}_dbg  "$<AND:${_${_lang}_${_id}},$<CONFIG:Debug>>")
+     set(_${_lang}_${_id}_rel  "$<AND:${_${_lang}_${_id}},$<CONFIG:Release>>")
+     set(_${_lang}_${_id}_rwdbg "$<AND:${_${_lang}_${_id}},$<CONFIG:RelWithDebInfo>>")
+     unset(_id)
+  endforeach ()
+
+  unset(_lang)
+endforeach ()
 
 
 #

Tools/CMake/AMReXParallelBackends.cmake

@@ -70,9 +70,7 @@ endif ()
 #
 #
 #
-if (  AMReX_GPU_BACKEND STREQUAL "CUDA"
-      AND
-      CMAKE_VERSION VERSION_GREATER_EQUAL 3.20 )
+if (AMReX_GPU_BACKEND STREQUAL "CUDA")
 
    find_package(CUDAToolkit REQUIRED)
    foreach(D IN LISTS AMReX_SPACEDIM)
@@ -82,11 +80,9 @@ if (  AMReX_GPU_BACKEND STREQUAL "CUDA"
            target_link_libraries(amrex_${D}d PUBLIC CUDA::cusparse)
        endif ()
 
-       if(CMAKE_CUDA_COMPILER_VERSION VERSION_LESS 11.2)
-           # nvToolsExt: if tiny profiler or base profiler are on.
-           if (AMReX_TINY_PROFILE OR AMReX_BASE_PROFILE)
-               target_link_libraries(amrex_${D}d PUBLIC CUDA::nvToolsExt)
-           endif ()
+       # if tiny profiler or base profiler are on we add range annotations
+       if (AMReX_TINY_PROFILE OR AMReX_BASE_PROFILE)
+           target_link_libraries(amrex_${D}d PUBLIC CUDA::nvtx3)
        endif ()
    endforeach()
 
@@ -378,14 +374,9 @@ if (AMReX_HIP)
        foreach(D IN LISTS AMReX_SPACEDIM)
            target_compile_options(amrex_${D}d PUBLIC
               $<$<COMPILE_LANGUAGE:CXX>:-fgpu-rdc> )
-           if(CMAKE_VERSION VERSION_LESS 3.18)
-               target_link_options(amrex_${D}d PUBLIC
-                  -fgpu-rdc)
-           else()
-               target_link_options(amrex_${D}d PUBLIC
-                  "$<$<LINK_LANGUAGE:HIP>:-fgpu-rdc>"
-                  "$<$<LINK_LANGUAGE:CXX>:-fgpu-rdc>")
-           endif()
+           target_link_options(amrex_${D}d PUBLIC
+              "$<$<LINK_LANGUAGE:HIP>:-fgpu-rdc>"
+              "$<$<LINK_LANGUAGE:CXX>:-fgpu-rdc>")
        endforeach()
    endif()
 endif ()

Tools/CMake/AMReXTargetHelpers.cmake

@@ -126,13 +126,7 @@ function (setup_target_for_cuda_compilation _target)
    set_target_properties( ${_target}
       PROPERTIES
       CUDA_SEPARABLE_COMPILATION ${AMReX_GPU_RDC}      # This adds -dc
+      CUDA_ARCHITECTURES "${AMREX_CUDA_ARCHS}"
    )
    set_cpp_sources_to_cuda_language(${_target})
-
-   if (CMAKE_VERSION VERSION_GREATER_EQUAL 3.20)
-      set_target_properties( ${_target}
-         PROPERTIES
-         CUDA_ARCHITECTURES "${AMREX_CUDA_ARCHS}"
-         )
-   endif ()
 endfunction ()