osb/cmake/TargetArch.cmake
Kai Blaschke e2251a0e8b
Add detection for ARM64 and remove PPC.
Also removed i386 as valid architecture for macOS, as it's no longer supported (even x86_64 is currently being phased out in favor of Silicon-based Macs).

ARM64 would also be required for a potential Raspberry Pi port (also needs a Vulkan or OpenGL ES renderer).
2024-02-19 14:11:14 +01:00

106 lines
4.2 KiB
CMake

# Based on the Qt 5 processor detection code, so should be very accurate
# https://qt.gitorious.org/qt/qtbase/blobs/master/src/corelib/global/qprocessordetection.h
# Currently handles arm (v5, v6, v7), x86 (32/64), ia64, and ppc (32/64)
# Regarding POWER/PowerPC, just as is noted in the Qt source,
# "There are many more known variants/revisions that we do not handle/detect."
set(archdetect_c_code "
#if defined(__arm__) || defined(__TARGET_ARCH_ARM)
#if defined(__ARM_ARCH_7__) \\
|| defined(__ARM_ARCH_7A__) \\
|| defined(__ARM_ARCH_7R__) \\
|| defined(__ARM_ARCH_7M__) \\
|| (defined(__TARGET_ARCH_ARM) && __TARGET_ARCH_ARM-0 >= 7)
#error cmake_ARCH armv7
#elif defined(__ARM_ARCH_6__) \\
|| defined(__ARM_ARCH_6J__) \\
|| defined(__ARM_ARCH_6T2__) \\
|| defined(__ARM_ARCH_6Z__) \\
|| defined(__ARM_ARCH_6K__) \\
|| defined(__ARM_ARCH_6ZK__) \\
|| defined(__ARM_ARCH_6M__) \\
|| (defined(__TARGET_ARCH_ARM) && __TARGET_ARCH_ARM-0 >= 6)
#error cmake_ARCH armv6
#elif defined(__ARM_ARCH_5TEJ__) \\
|| (defined(__TARGET_ARCH_ARM) && __TARGET_ARCH_ARM-0 >= 5)
#error cmake_ARCH armv5
#else
#error cmake_ARCH arm
#endif
#elif defined(__arm64__)
#error cmake_ARCH arm64
#elif defined(__i386) || defined(__i386__) || defined(_M_IX86)
#error cmake_ARCH i386
#elif defined(__x86_64) || defined(__x86_64__) || defined(__amd64) || defined(_M_X64)
#error cmake_ARCH x86_64
#elif defined(__ia64) || defined(__ia64__) || defined(_M_IA64)
#error cmake_ARCH ia64
#endif
#error cmake_ARCH unknown
")
function(target_architecture output_var)
if(CMAKE_SYSTEM_NAME STREQUAL "Darwin" AND CMAKE_OSX_ARCHITECTURES)
# On macOS, we use CMAKE_OSX_ARCHITECTURES *if* it was set
# Apple currently only supports x86_64 and arm64 architectures to target Intel-based
# and Silicon-based Macs. Building as a universal binary will make each machine
# use the proper native code to run the resulting executable.
foreach(osx_arch ${CMAKE_OSX_ARCHITECTURES})
if("${osx_arch}" STREQUAL "x86_64")
set(osx_arch_x86_64 TRUE)
elseif("${osx_arch}" STREQUAL "arm64")
set(osx_arch_arm64 TRUE)
else()
message(FATAL_ERROR "Invalid OS X arch name: ${osx_arch}")
endif()
endforeach()
if(osx_arch_x86_64)
list(APPEND ARCH x86_64)
endif()
if(osx_arch_arm64)
list(APPEND ARCH arm64)
endif()
else()
file(WRITE "${CMAKE_BINARY_DIR}/arch.c" "${archdetect_c_code}")
enable_language(C)
# Detect the architecture in a rather creative way...
# This compiles a small C program which is a series of ifdefs that selects a
# particular #error preprocessor directive whose message string contains the
# target architecture. The program will always fail to compile (both because
# file is not a valid C program, and obviously because of the presence of the
# #error preprocessor directives... but by exploiting the preprocessor in this
# way, we can detect the correct target architecture even when cross-compiling,
# since the program itself never needs to be run (only the compiler/preprocessor)
try_run(
run_result_unused
compile_result_unused
"${CMAKE_BINARY_DIR}"
"${CMAKE_BINARY_DIR}/arch.c"
COMPILE_OUTPUT_VARIABLE ARCH
CMAKE_FLAGS CMAKE_OSX_ARCHITECTURES=${CMAKE_OSX_ARCHITECTURES}
)
# Parse the architecture name from the compiler output
string(REGEX MATCH "cmake_ARCH ([a-zA-Z0-9_]+)" ARCH "${ARCH}")
# Get rid of the value marker leaving just the architecture name
string(REPLACE "cmake_ARCH " "" ARCH "${ARCH}")
# If we are compiling with an unknown architecture this variable should
# already be set to "unknown" but in the case that it's empty (i.e. due
# to a typo in the code), then set it to unknown
if (NOT ARCH)
set(ARCH unknown)
endif()
endif()
set(${output_var} "${ARCH}" PARENT_SCOPE)
endfunction()