blob: b40b5d12902a0608833b062984150b4cfc8fa68c [file] [log] [blame]
# ------------------------------------------------------------------------------
# Cpu features definition and flags
# ------------------------------------------------------------------------------
# Initialize ALL_CPU_FEATURES as empty list.
set(ALL_CPU_FEATURES "")
if(${LIBC_TARGET_ARCHITECTURE_IS_X86})
set(ALL_CPU_FEATURES SSE2 SSE4_2 AVX2 AVX512F)
set(LIBC_COMPILE_OPTIONS_NATIVE -march=native)
elseif(${LIBC_TARGET_ARCHITECTURE_IS_AARCH64})
set(LIBC_COMPILE_OPTIONS_NATIVE -mcpu=native)
endif()
# Making sure ALL_CPU_FEATURES is sorted.
list(SORT ALL_CPU_FEATURES)
# Function to check whether the target CPU supports the provided set of features.
# Usage:
# cpu_supports(
# <output variable>
# <list of cpu features>
# )
function(cpu_supports output_var features)
_intersection(var "${LIBC_CPU_FEATURES}" "${features}")
if("${var}" STREQUAL "${features}")
set(${output_var} TRUE PARENT_SCOPE)
else()
unset(${output_var} PARENT_SCOPE)
endif()
endfunction()
# ------------------------------------------------------------------------------
# Internal helpers and utilities.
# ------------------------------------------------------------------------------
# Computes the intersection between two lists.
function(_intersection output_var list1 list2)
foreach(element IN LISTS list1)
if("${list2}" MATCHES "(^|;)${element}(;|$)")
list(APPEND tmp "${element}")
endif()
endforeach()
set(${output_var} ${tmp} PARENT_SCOPE)
endfunction()
# Generates a cpp file to introspect the compiler defined flags.
function(_generate_check_code)
foreach(feature IN LISTS ALL_CPU_FEATURES)
set(DEFINITIONS
"${DEFINITIONS}
#ifdef __${feature}__
\"${feature}\",
#endif")
endforeach()
configure_file(
"${LIBC_SOURCE_DIR}/cmake/modules/cpu_features/check_cpu_features.cpp.in"
"cpu_features/check_cpu_features.cpp" @ONLY)
endfunction()
_generate_check_code()
set(LIBC_CPU_FEATURES "" CACHE PATH "Host supported CPU features")
if(CMAKE_CROSSCOMPILING)
_intersection(cpu_features "${ALL_CPU_FEATURES}" "${LIBC_CPU_FEATURES}")
if(NOT "${cpu_features}" STREQUAL "${LIBC_CPU_FEATURES}")
message(FATAL_ERROR "Unsupported CPU features: ${cpu_features}")
endif()
set(LIBC_CPU_FEATURES "${cpu_features}")
else()
# Populates the LIBC_CPU_FEATURES list from host.
try_run(
run_result compile_result "${CMAKE_CURRENT_BINARY_DIR}/check_${feature}"
"${CMAKE_CURRENT_BINARY_DIR}/cpu_features/check_cpu_features.cpp"
COMPILE_DEFINITIONS ${LIBC_COMPILE_OPTIONS_NATIVE}
COMPILE_OUTPUT_VARIABLE compile_output
RUN_OUTPUT_VARIABLE run_output)
if("${run_result}" EQUAL 0)
set(LIBC_CPU_FEATURES "${run_output}")
elseif(NOT ${compile_result})
message(FATAL_ERROR "Failed to compile: ${compile_output}")
else()
message(FATAL_ERROR "Failed to run: ${run_output}")
endif()
endif()