if(CMAKE_TOOLCHAIN_FILE)
    set(LIBRARY_OUTPUT_PATH_ROOT ${CMAKE_BINARY_DIR} CACHE PATH "root for library output, set this to change where android libs are compiled to")
    # get absolute path, but get_filename_component ABSOLUTE only refer with source dir, so find_file here :(
    get_filename_component(CMAKE_TOOLCHAIN_FILE_NAME ${CMAKE_TOOLCHAIN_FILE} NAME)
    find_file(CMAKE_TOOLCHAIN_FILE ${CMAKE_TOOLCHAIN_FILE_NAME} PATHS ${CMAKE_SOURCE_DIR} NO_DEFAULT_PATH)
    message(STATUS "CMAKE_TOOLCHAIN_FILE = ${CMAKE_TOOLCHAIN_FILE}")
endif()

if(NOT DEFINED CMAKE_INSTALL_PREFIX)
    set(CMAKE_INSTALL_PREFIX "${CMAKE_BINARY_DIR}/install" CACHE PATH "Installation Directory")
endif()
message(STATUS "CMAKE_INSTALL_PREFIX = ${CMAKE_INSTALL_PREFIX}")

if(NOT DEFINED NCNN_VERSION)
    string(TIMESTAMP NCNN_VERSION "%Y%m%d")
endif()

set(NCNN_VERSION_MAJOR 1)
set(NCNN_VERSION_MINOR 0)
set(NCNN_VERSION_PATCH ${NCNN_VERSION})
set(NCNN_VERSION_STRING ${NCNN_VERSION_MAJOR}.${NCNN_VERSION_MINOR}.${NCNN_VERSION_PATCH})
message(STATUS "NCNN_VERSION_STRING = ${NCNN_VERSION_STRING}")

cmake_minimum_required(VERSION 2.8.12)

if(NOT CMAKE_BUILD_TYPE)
    set(CMAKE_BUILD_TYPE release CACHE STRING "Choose the type of build" FORCE)
endif()

if(NOT CMAKE_VERSION VERSION_LESS "3.15")
    # enable CMAKE_MSVC_RUNTIME_LIBRARY
    cmake_policy(SET CMP0091 NEW)
endif()

if(POLICY CMP0025)
    # reference from https://cmake.org/cmake/help/latest/policy/CMP0025.html
    cmake_policy(SET CMP0025 NEW)
endif()

if(POLICY CMP0057)
    # reference from https://cmake.org/cmake/help/latest/policy/CMP0057.html
    cmake_policy(SET CMP0057 NEW)
endif()

project(ncnn)

if(MSVC AND NOT CMAKE_VERSION VERSION_LESS "3.15")
    option(NCNN_BUILD_WITH_STATIC_CRT "Enables use of statically linked CRT for statically linked ncnn" OFF)
    if(NCNN_BUILD_WITH_STATIC_CRT)
        # cmake before version 3.15 not work
        set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
    endif()
endif()

option(NCNN_SHARED_LIB "shared library support" OFF)
option(NCNN_ENABLE_LTO "enable link-time optimization" OFF)
option(NCNN_OPENMP "openmp support" ON)
option(NCNN_STDIO "load model from external file" ON)
option(NCNN_STRING "plain and verbose string" ON)
option(NCNN_INSTALL_SDK "install ncnn library and headers" ON)
option(NCNN_SIMPLEOCV "minimal opencv structure emulation" OFF)
option(NCNN_SIMPLEOMP "minimal openmp runtime emulation" OFF)
option(NCNN_SIMPLESTL "minimal cpp stl structure emulation" OFF)
option(NCNN_SIMPLEMATH "minimal cmath" OFF)
option(NCNN_THREADS "build with threads" ON)
option(NCNN_BENCHMARK "print benchmark information for every layer" OFF)
option(NCNN_C_API "build with C api" ON)
option(NCNN_PLATFORM_API "build with platform api candy" ON)
option(NCNN_PIXEL "convert and resize from/to image pixel" ON)
option(NCNN_PIXEL_ROTATE "rotate image pixel orientation" ON)
option(NCNN_PIXEL_AFFINE "warp affine image pixel" ON)
option(NCNN_PIXEL_DRAWING "draw basic figure and text" ON)
option(NCNN_CMAKE_VERBOSE "print verbose cmake messages" OFF)
option(NCNN_VULKAN "vulkan compute support" OFF)
option(NCNN_SIMPLEVK "minimal in-house vulkan loader" ON)
option(NCNN_SYSTEM_GLSLANG "use system glslang library" OFF)
option(NCNN_RUNTIME_CPU "runtime dispatch cpu routines" ON)
option(NCNN_DISABLE_PIC "disable position-independent code" OFF)
option(NCNN_BUILD_TESTS "build tests" OFF)
option(NCNN_COVERAGE "build for coverage" OFF)
option(NCNN_ASAN "build for address sanitizer" OFF)
option(NCNN_BUILD_BENCHMARK "build benchmark" ON)
option(NCNN_PYTHON "build python api" OFF)
option(NCNN_INT8 "int8 inference" ON)
option(NCNN_BF16 "bf16 inference" ON)
option(NCNN_FORCE_INLINE "force inline some function" ON)

if(ANDROID OR IOS OR NCNN_SIMPLESTL)
    option(NCNN_DISABLE_RTTI "disable rtti" ON)
    option(NCNN_DISABLE_EXCEPTION "disable exception" ON)
else()
    option(NCNN_DISABLE_RTTI "disable rtti" OFF)
    option(NCNN_DISABLE_EXCEPTION "disable exception" OFF)
endif()

if(ANDROID OR IOS OR NCNN_SIMPLESTL OR CMAKE_CROSSCOMPILING)
    option(NCNN_BUILD_TOOLS "build tools" OFF)
    option(NCNN_BUILD_EXAMPLES "build examples" OFF)
else()
    option(NCNN_BUILD_TOOLS "build tools" ON)
    option(NCNN_BUILD_EXAMPLES "build examples" ON)
endif()

if(NCNN_SHARED_LIB)
    if(NCNN_ENABLE_LTO)
        # enable global link time optimization
        cmake_policy(SET CMP0069 NEW)
        set(CMAKE_POLICY_DEFAULT_CMP0069 NEW)
        include(CheckIPOSupported)
        check_ipo_supported(RESULT ipo_supported OUTPUT ipo_supported_output)
        if(ipo_supported)
            set(CMAKE_INTERPROCEDURAL_OPTIMIZATION TRUE)
        else()
            message(WARNING "IPO is not supported: ${ipo_supported_output}")
            set(NCNN_ENABLE_LTO OFF)
        endif()
    endif()
endif()

if(NOT NCNN_STDIO OR NOT NCNN_STRING)
    if(NCNN_BUILD_TOOLS)
        message(WARNING "NCNN_STDIO or NCNN_STRING disabled, NCNN_BUILD_TOOLS will be turned off.")
        set(NCNN_BUILD_TOOLS OFF)
    endif()
    if(NCNN_BUILD_EXAMPLES)
        message(WARNING "NCNN_STDIO or NCNN_STRING disabled, NCNN_BUILD_EXAMPLES will be turned off.")
        set(NCNN_BUILD_EXAMPLES OFF)
    endif()
    if(NCNN_BUILD_BENCHMARK)
        message(WARNING "NCNN_STDIO or NCNN_STRING disabled, NCNN_BUILD_BENCHMARK will be turned off.")
        set(NCNN_BUILD_BENCHMARK OFF)
    endif()
    if(NCNN_BUILD_TESTS)
        message(WARNING "NCNN_STDIO or NCNN_STRING disabled, NCNN_BUILD_TESTS will be turned off.")
        set(NCNN_BUILD_TESTS OFF)
    endif()
endif()

##############################################

include(CheckCXXCompilerFlag)
set(CMAKE_TRY_COMPILE_CONFIGURATION release)

# gnu inline assembly in clang msvc does not work actually
if(NOT (CMAKE_CXX_COMPILER_ID MATCHES "MSVC" OR (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND CMAKE_CXX_SIMULATE_ID MATCHES "MSVC" AND CMAKE_CXX_COMPILER_FRONTEND_VARIANT MATCHES "MSVC")))
    check_cxx_source_compiles("int main() { int a = 0; asm volatile(\"\" : \"=r\"(a) : \"0\"(a) : \"memory\"); return 0; }" NCNN_COMPILER_SUPPORT_GNU_INLINE_ASM)
    if(NCNN_COMPILER_SUPPORT_GNU_INLINE_ASM)
        option(NCNN_GNU_INLINE_ASM "optimize platform with gnu style inline assembly" ON)
    else()
        message(WARNING "The compiler does not support gnu style inline assembly. NCNN_GNU_INLINE_ASM will be OFF.")
    endif()
endif()

if((IOS AND CMAKE_OSX_ARCHITECTURES MATCHES "arm")
    OR (APPLE AND CMAKE_OSX_ARCHITECTURES MATCHES "arm64")
    OR (CMAKE_SYSTEM_PROCESSOR MATCHES "^(arm|aarch64)")
    OR (CMAKE_CXX_COMPILER_ARCHITECTURE_ID MATCHES "(ARMV7|ARM64)")
    OR ((CMAKE_CXX_COMPILER_ID MATCHES "MSVC" OR (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND CMAKE_CXX_SIMULATE_ID MATCHES "MSVC" AND CMAKE_CXX_COMPILER_FRONTEND_VARIANT MATCHES "MSVC")) AND (${CMAKE_GENERATOR_PLATFORM} MATCHES "^(arm|arm64)")))
    set(NCNN_TARGET_ARCH arm)

    if(APPLE AND CMAKE_OSX_ARCHITECTURES STREQUAL "arm64_32")
        set(NCNN_TARGET_ILP32 TRUE)
    endif()

    if(CMAKE_SIZEOF_VOID_P EQUAL 4 AND NOT NCNN_TARGET_ILP32)
        check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _s, _a, _b; _s = vmlaq_f32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM_NEON)

        if(NCNN_COMPILER_SUPPORT_ARM_NEON)
            if(CMAKE_CXX_COMPILER_ID MATCHES "MSVC" OR (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND CMAKE_CXX_SIMULATE_ID MATCHES "MSVC" AND CMAKE_CXX_COMPILER_FRONTEND_VARIANT MATCHES "MSVC"))
                set(CMAKE_REQUIRED_FLAGS "/arch:VFPv4")
                check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _a; float16x4_t _s = vcvt_f16_f32(_a); return 0; }" NCNN_COMPILER_SUPPORT_ARM_VFPV4)

                unset(CMAKE_REQUIRED_FLAGS)
            else()
                set(CMAKE_REQUIRED_FLAGS "-mfpu=neon-vfpv4")
                check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _a; float16x4_t _s = vcvt_f16_f32(_a); return 0; }" NCNN_COMPILER_SUPPORT_ARM_VFPV4)

                if(NOT NCNN_COMPILER_SUPPORT_ARM_VFPV4)
                    set(CMAKE_REQUIRED_FLAGS "-mfpu=neon-vfpv4 -mfp16-format=ieee")
                    check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _a; float16x4_t _s = vcvt_f16_f32(_a); return 0; }" NCNN_COMPILER_SUPPORT_ARM_VFPV4_FP16)
                endif()

                unset(CMAKE_REQUIRED_FLAGS)
            endif()
        endif()

        if(NCNN_COMPILER_SUPPORT_ARM_VFPV4 OR NCNN_COMPILER_SUPPORT_ARM_VFPV4_FP16)
            option(NCNN_VFPV4 "optimize armv7 platform with vfpv4" ON)
        else()
            message(WARNING "The compiler does not support arm vfpv4. NCNN_VFPV4 will be OFF.")
        endif()
    endif()

    if(CMAKE_SIZEOF_VOID_P EQUAL 8 OR NCNN_TARGET_ILP32)
        if(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.0")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _a; float16x4_t _s = vcvt_f16_f32(_a); return 0; }" NCNN_COMPILER_SUPPORT_ARM_VFPV4)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.2")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float16x8_t _s, _a, _b; _s = vfmaq_f16(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM82_FP16)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.2")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { int32x4_t _s; int8x16_t _a, _b; _s = vdotq_s32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM82_DOTPROD)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.2")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _s; float16x8_t _a, _b; _s = vfmlalq_low_f16(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM82_FP16FML)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.4")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _s; bfloat16x8_t _a, _b; _s = vcvt_f32_bf16(vcvt_bf16_f32(vbfmmlaq_f32(_s, _a, _b))); return 0; }" NCNN_COMPILER_SUPPORT_ARM84_BF16)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.4")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { int32x4_t _s; int8x16_t _a, _b; _s = vmmlaq_s32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM84_I8MM)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.6")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svfloat16_t _s, _a, _b; svbool_t bp; _s = svmla_f16_z(bp, _s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVE)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.6")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svint16_t _s; svint8_t _a, _b; _s = svmlslb_s16(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVE2)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.6")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svfloat32_t _s; svbfloat16_t _a, _b; _s = svbfmmla_f32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVEBF16)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.6")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svint32_t _s; svint8_t _a, _b; _s = svmmla_s32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVEI8MM)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.6")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svfloat32_t _s, _a, _b; _s = svmmla_f32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVEF32MM)

            unset(CMAKE_REQUIRED_FLAGS)
        elseif(CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND CMAKE_CXX_SIMULATE_ID MATCHES "MSVC" AND CMAKE_CXX_COMPILER_FRONTEND_VARIANT MATCHES "MSVC")
            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.0")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _a; float16x4_t _s = vcvt_f16_f32(_a); return 0; }" NCNN_COMPILER_SUPPORT_ARM_VFPV4)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.2 -march=armv8.2-a+fp16")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float16x8_t _s, _a, _b; _s = vfmaq_f16(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM82_FP16)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.2 -march=armv8.2-a+dotprod")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { int32x4_t _s; int8x16_t _a, _b; _s = vdotq_s32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM82_DOTPROD)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.2 -march=armv8.2-a+fp16fml")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _s; float16x8_t _a, _b; _s = vfmlalq_low_f16(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM82_FP16FML)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.4 -march=armv8.4-a+bf16")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _s; bfloat16x8_t _a, _b; _s = vcvt_f32_bf16(vcvt_bf16_f32(vbfmmlaq_f32(_s, _a, _b))); return 0; }" NCNN_COMPILER_SUPPORT_ARM84_BF16)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.4 -march=armv8.4-a+i8mm")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { int32x4_t _s; int8x16_t _a, _b; _s = vmmlaq_s32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM84_I8MM)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.6 -march=armv8.6-a+sve")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svfloat16_t _s, _a, _b; svbool_t bp; _s = svmla_f16_z(bp, _s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVE)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.6 -march=armv8.6-a+sve2")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svint16_t _s; svint8_t _a, _b; _s = svmlslb_s16(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVE2)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.6 -march=armv8.6-a+sve+bf16")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svfloat32_t _s; svbfloat16_t _a, _b; _s = svbfmmla_f32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVEBF16)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.6 -march=armv8.6-a+sve+i8mm")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svint32_t _s; svint8_t _a, _b; _s = svmmla_s32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVEI8MM)

            set(CMAKE_REQUIRED_FLAGS "/arch:armv8.6 -march=armv8.6-a+sve+f32mm")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svfloat32_t _s, _a, _b; _s = svmmla_f32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVEF32MM)

            unset(CMAKE_REQUIRED_FLAGS)
        else()
            set(CMAKE_REQUIRED_FLAGS "-march=armv8-a")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _a; float16x4_t _s = vcvt_f16_f32(_a); return 0; }" NCNN_COMPILER_SUPPORT_ARM_VFPV4)

            set(CMAKE_REQUIRED_FLAGS "-march=armv8.2-a+fp16")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float16x8_t _s, _a, _b; _s = vfmaq_f16(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM82_FP16)

            set(CMAKE_REQUIRED_FLAGS "-march=armv8.2-a+dotprod")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { int32x4_t _s; int8x16_t _a, _b; _s = vdotq_s32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM82_DOTPROD)

            set(CMAKE_REQUIRED_FLAGS "-march=armv8.2-a+fp16fml")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _s; float16x8_t _a, _b; _s = vfmlalq_low_f16(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM82_FP16FML)

            set(CMAKE_REQUIRED_FLAGS "-march=armv8.4-a+bf16")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { float32x4_t _s; bfloat16x8_t _a, _b; _s = vcvt_f32_bf16(vcvt_bf16_f32(vbfmmlaq_f32(_s, _a, _b))); return 0; }" NCNN_COMPILER_SUPPORT_ARM84_BF16)

            set(CMAKE_REQUIRED_FLAGS "-march=armv8.4-a+i8mm")
            check_cxx_source_compiles("#include <arm_neon.h>\nint main() { int32x4_t _s; int8x16_t _a, _b; _s = vmmlaq_s32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM84_I8MM)

            set(CMAKE_REQUIRED_FLAGS "-march=armv8.6-a+sve")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svfloat16_t _s, _a, _b; svbool_t bp; _s = svmla_f16_z(bp, _s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVE)

            set(CMAKE_REQUIRED_FLAGS "-march=armv8.6-a+sve2")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svint16_t _s; svint8_t _a, _b; _s = svmlslb_s16(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVE2)

            set(CMAKE_REQUIRED_FLAGS "-march=armv8.6-a+sve+bf16")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svfloat32_t _s; svbfloat16_t _a, _b; _s = svbfmmla_f32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVEBF16)

            set(CMAKE_REQUIRED_FLAGS "-march=armv8.6-a+sve+i8mm")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svint32_t _s; svint8_t _a, _b; _s = svmmla_s32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVEI8MM)

            set(CMAKE_REQUIRED_FLAGS "-march=armv8.6-a+sve+f32mm")
            check_cxx_source_compiles("#include <arm_sve.h>\nint main() { svfloat32_t _s, _a, _b; _s = svmmla_f32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_ARM86_SVEF32MM)

            unset(CMAKE_REQUIRED_FLAGS)
        endif()

        if(NCNN_COMPILER_SUPPORT_ARM_VFPV4)
            option(NCNN_VFPV4 "optimize aarch64 platform with vfpv4" ON)
        else()
            message(WARNING "The compiler does not support arm vfpv4. NCNN_VFPV4 will be OFF.")
        endif()

        if(NCNN_COMPILER_SUPPORT_ARM82_FP16)
            option(NCNN_ARM82 "optimize aarch64 platform with armv8.2 fp16" ON)
            if(NCNN_COMPILER_SUPPORT_ARM82_DOTPROD)
                if(NCNN_ARM82)
                    option(NCNN_ARM82DOT "optimize aarch64 platform with armv8.2 dotprod" ON)
                endif()
            else()
                message(WARNING "The compiler does not support armv8.2 dotprod. NCNN_ARM82DOT will be OFF.")
            endif()
            if(NCNN_COMPILER_SUPPORT_ARM82_FP16FML)
                if(NCNN_ARM82)
                    option(NCNN_ARM82FP16FML "optimize aarch64 platform with armv8.2 fp16fml" ON)
                endif()
            else()
                message(WARNING "The compiler does not support armv8.2 fp16fml. NCNN_ARM82FP16FML will be OFF.")
            endif()
            if(NCNN_COMPILER_SUPPORT_ARM84_BF16)
                if(NCNN_ARM82DOT AND NCNN_ARM82FP16FML)
                    option(NCNN_ARM84BF16 "optimize aarch64 platform with armv8.4 bf16" ON)
                endif()
            else()
                message(WARNING "The compiler does not support armv8.4 bf16. NCNN_ARM86BF16 will be OFF.")
            endif()
            if(NCNN_COMPILER_SUPPORT_ARM84_I8MM)
                if(NCNN_ARM82DOT AND NCNN_ARM82FP16FML)
                    option(NCNN_ARM84I8MM "optimize aarch64 platform with armv8.4 i8mm" ON)
                endif()
            else()
                message(WARNING "The compiler does not support armv8.4 i8mm. NCNN_ARM84I8MM will be OFF.")
            endif()
            if(NCNN_COMPILER_SUPPORT_ARM86_SVE)
                if(NCNN_ARM84BF16 AND NCNN_ARM84I8MM)
                    option(NCNN_ARM86SVE "optimize aarch64 platform with armv8.6 sve" ON)
                    if(NCNN_COMPILER_SUPPORT_ARM86_SVE2)
                        if(NCNN_ARM86SVE)
                            option(NCNN_ARM86SVE2 "optimize aarch64 platform with armv8.6 sve2" ON)
                        endif()
                    else()
                        message(WARNING "The compiler does not support armv8.6 sve2. NCNN_ARM86SVE2 will be OFF.")
                    endif()
                    if(NCNN_COMPILER_SUPPORT_ARM86_SVEBF16)
                        if(NCNN_ARM86SVE)
                            option(NCNN_ARM86SVEBF16 "optimize aarch64 platform with armv8.6 sve bf16" ON)
                        endif()
                    else()
                        message(WARNING "The compiler does not support armv8.6 sve bf16. NCNN_ARM86SVEBF16 will be OFF.")
                    endif()
                    if(NCNN_COMPILER_SUPPORT_ARM86_SVEI8MM)
                        if(NCNN_ARM86SVE)
                            option(NCNN_ARM86SVEI8MM "optimize aarch64 platform with armv8.6 sve i8mm" ON)
                        endif()
                    else()
                        message(WARNING "The compiler does not support armv8.6 sve i8mm. NCNN_ARM86SVEI8MM will be OFF.")
                    endif()
                    if(NCNN_COMPILER_SUPPORT_ARM86_SVEF32MM)
                        if(NCNN_ARM86SVE)
                            option(NCNN_ARM86SVEF32MM "optimize aarch64 platform with armv8.6 sve f32mm" ON)
                        endif()
                    else()
                        message(WARNING "The compiler does not support armv8.6 sve f32mm. NCNN_ARM86SVEF32MM will be OFF.")
                    endif()
                endif()
            else()
                message(WARNING "The compiler does not support armv8.6 sve. NCNN_ARM86SVE will be OFF.")
            endif()
        else()
            message(WARNING "The compiler does not support armv8.2 fp16. NCNN_ARM82 will be OFF.")
        endif()
    endif()
elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(mips)")
    set(NCNN_TARGET_ARCH mips)

    check_cxx_compiler_flag("-mmsa" NCNN_COMPILER_SUPPORT_MIPS_MSA)

    set(CMAKE_REQUIRED_FLAGS "-mloongson-mmi -I${CMAKE_CURRENT_SOURCE_DIR}/src/layer/mips")
    check_cxx_source_compiles("#include \"loongson_mmi.h\"\nint main() { int16x4_t _a, _b; int32x2_t _s = __mmi_pmaddhw(_a, _b); return 0; }" NCNN_COMPILER_SUPPORT_LOONGSON_MMI)

    unset(CMAKE_REQUIRED_FLAGS)

    if(NCNN_COMPILER_SUPPORT_MIPS_MSA)
        option(NCNN_MSA "optimize mips platform with msa extension" ON)
    else()
        message(WARNING "The compiler does not support msa extension. NCNN_MSA will be OFF.")
    endif()
    if(NCNN_COMPILER_SUPPORT_LOONGSON_MMI)
        option(NCNN_MMI "optimize mips platform with loongson mmi extension" ON)
    else()
        message(WARNING "The compiler does not support loongson mmi extension. NCNN_MMI will be OFF.")
    endif()
elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(loongarch64|loongarch32)")
    set(NCNN_TARGET_ARCH loongarch)

    set(CMAKE_REQUIRED_FLAGS "-mlsx")
    check_cxx_source_compiles("#include <lsxintrin.h>\nint main() { __m128 _s, _a, _b, _c; _s = __lsx_vfmadd_s(_a, _b, _c); return 0; }" NCNN_COMPILER_SUPPORT_LOONGARCH_LSX)

    set(CMAKE_REQUIRED_FLAGS "-mlasx")
    check_cxx_source_compiles("#include <lasxintrin.h>\nint main() { __m256 _s, _a, _b, _c; _s = __lasx_xvfmadd_s(_a, _b, _c); return 0; }" NCNN_COMPILER_SUPPORT_LOONGARCH_LASX)

    unset(CMAKE_REQUIRED_FLAGS)

    if(NCNN_COMPILER_SUPPORT_LOONGARCH_LSX)
        option(NCNN_LSX "optimize loongarch platform with lsx extension" ON)
        if(NCNN_COMPILER_SUPPORT_LOONGARCH_LASX)
            option(NCNN_LASX "optimize loongarch platform with lasx extension" ON)
        else()
            message(WARNING "The compiler does not support lasx extension. NCNN_LASX will be OFF.")
        endif()
    else()
        message(WARNING "The compiler does not support lsx extension. NCNN_LSX will be OFF.")
    endif()

elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(riscv)")
    set(NCNN_TARGET_ARCH riscv)

    if(CMAKE_SIZEOF_VOID_P EQUAL 8)
        set(CMAKE_REQUIRED_FLAGS "-march=rv64gcv")
        check_cxx_source_compiles("#include <riscv_vector.h>\nint main() { vfloat32m8_t _s, _w; float _v; size_t vl; _s = __riscv_vfmacc_vf_f32m8(_s, _v, _w, vl); vfloat32m1_t _x; vfloat32m1x2_t _xx = __riscv_vcreate_v_f32m1x2(_x, _x); return 0; }" NCNN_COMPILER_SUPPORT_RISCV_V)

        set(CMAKE_REQUIRED_FLAGS "-march=rv64gc_zfh -D__fp16=_Float16")
        check_cxx_source_compiles("int main() { __fp16 s, v; s = v * v; return 0; }" NCNN_COMPILER_SUPPORT_RISCV_ZFH)

        set(CMAKE_REQUIRED_FLAGS "-march=rv64gcv_zfh_zvfh -D__fp16=_Float16")
        check_cxx_source_compiles("#include <riscv_vector.h>\nint main() { vfloat16m8_t _s, _w; __fp16 _v; size_t vl; _s = __riscv_vfmacc_vf_f16m8(_s, _v, _w, vl); return 0; }" NCNN_COMPILER_SUPPORT_RISCV_ZVFH)

        set(CMAKE_REQUIRED_FLAGS "-march=rv64gc_zfh_xtheadvector -D__fp16=_Float16")
        check_cxx_source_compiles("#include <riscv_vector.h>\nint main() { vfloat16m8_t _s, _w; __fp16 _v; size_t vl; _s = __riscv_vfmacc_vf_f16m8(_s, _v, _w, vl); vfloat32m1_t _x; vfloat32m1x2_t _xx = __riscv_vcreate_v_f32m1x2(_x, _x); return 0; }" NCNN_COMPILER_SUPPORT_RISCV_XTHEADVECTOR)

        unset(CMAKE_REQUIRED_FLAGS)

        if(NCNN_COMPILER_SUPPORT_RISCV_V OR NCNN_COMPILER_SUPPORT_RISCV_XTHEADVECTOR)
            option(NCNN_RVV "optimize risc-v platform with v extension" ON)
        else()
            message(WARNING "The compiler does not support risc-v v or xtheadvector extension. NCNN_RVV will be OFF.")
        endif()

        if(NCNN_COMPILER_SUPPORT_RISCV_XTHEADVECTOR)
            option(NCNN_XTHEADVECTOR "optimize risc-v platform with xtheadvector extension" ON)
        else()
            message(WARNING "The compiler does not support risc-v xtheadvector extension. NCNN_XTHEADVECTOR will be OFF.")
        endif()

        if(NCNN_COMPILER_SUPPORT_RISCV_ZFH)
            option(NCNN_ZFH "optimize risc-v platform with zfh extension" ON)
            if(NCNN_COMPILER_SUPPORT_RISCV_ZVFH OR NCNN_COMPILER_SUPPORT_RISCV_XTHEADVECTOR)
                if(NCNN_RVV AND NCNN_ZFH)
                    option(NCNN_ZVFH "optimize risc-v platform with zvfh extension" ON)
                endif()
            else()
                message(WARNING "The compiler does not support zvfh extension. NCNN_ZVFH will be OFF.")
            endif()
        else()
            message(WARNING "The compiler does not support risc-v zfh extension. NCNN_ZFH will be OFF.")
        endif()

    endif()
elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(powerpc|ppc)")
    set(NCNN_TARGET_ARCH powerpc)

    if(NCNN_PPC64LE_VSX)
        set(NCNN_TARGET_ARCH x86)

        set(CMAKE_REQUIRED_FLAGS "-DNO_WARN_X86_INTRINSICS -D__SSE2__")
        check_cxx_source_compiles("#include <emmintrin.h>\nint main() { return 0; }" NCNN_COMPILER_SUPPORT_PPC64LE_SSE2)
        unset(CMAKE_REQUIRED_FLAGS)

        set(CMAKE_REQUIRED_FLAGS "-DNO_WARN_X86_INTRINSICS -D__SSE4_1__")
        check_cxx_source_compiles("#include <smmintrin.h>\nint main() { __m128i _v, _a, _b; _v = _mm_packus_epi32(_a, _b); return 0; }" NCNN_COMPILER_SUPPORT_PPC64LE_SSE41)
        unset(CMAKE_REQUIRED_FLAGS)

        if(NCNN_COMPILER_SUPPORT_PPC64LE_SSE2)
            option(NCNN_VSX_SSE2 "optimize ppc64le platform with sse2 extension" ON)
        else()
            message(WARNING "The compiler does not support sse2 extension. NCNN_VSX_SSE2 will be OFF.")
        endif()

        if(NCNN_COMPILER_SUPPORT_PPC64LE_SSE41)
            option(NCNN_VSX_SSE41 "optimize ppc64le platform with sse4.1 extension" ON)
        else()
            message(WARNING "The compiler does not support sse4.1 extension. NCNN_VSX_SSE41 will be OFF.")
        endif()
    endif()
elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(xtensa)")
    set(NCNN_TARGET_ARCH xtensa)
elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(s390x)")
    set(NCNN_TARGET_ARCH s390x)
elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "^(sw_64)")
    set(NCNN_TARGET_ARCH sw_64)
    #sw_64 is alpha-like platform
    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mieee")
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mieee")
else()
    set(NCNN_TARGET_ARCH x86)

    option(NCNN_SSE2 "optimize x86 platform with sse2 extension" ON)

    if(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
        check_cxx_compiler_flag("/arch:AVX" NCNN_COMPILER_SUPPORT_X86_AVX)
        check_cxx_compiler_flag("/arch:AVX" NCNN_COMPILER_SUPPORT_X86_FMA)
        check_cxx_compiler_flag("/arch:AVX" NCNN_COMPILER_SUPPORT_X86_XOP)
        check_cxx_compiler_flag("/arch:AVX" NCNN_COMPILER_SUPPORT_X86_F16C)
        check_cxx_compiler_flag("/arch:AVX2" NCNN_COMPILER_SUPPORT_X86_AVX2)
        check_cxx_compiler_flag("/arch:AVX512" NCNN_COMPILER_SUPPORT_X86_AVX512)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX2")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256i _s, _a, _b; _s = _mm256_dpwssd_avx_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_VNNI)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX2")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256i _s, _a, _b; _s = _mm256_dpbssd_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_VNNI_INT8)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX2")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256i _s, _a, _b; _s = _mm256_dpwsud_avx_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_VNNI_INT16)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX2")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256 _a; __m128bh _s = _mm256_cvtneps_avx_pbh(_a); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_NE_CONVERT)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX512")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m512i _s, _a, _b; _s = _mm512_dpwssd_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX512_VNNI)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX512")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256bh _s; __m512bh _a, _b; _s = _mm512_cvtneps_pbh(_mm512_dpbf16_ps(_mm512_cvtpbh_ps(_s), _a, _b)); return 0; }\n__m512i t(__m512 a) { __m256i _a = (__m256i)_mm512_cvtneps_pbh(a); return _mm512_inserti32x8(_mm512_castsi256_si512(_a), _a, 1); }" NCNN_COMPILER_SUPPORT_X86_AVX512_BF16)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX512")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m512h _s, _a, _b; _s = _mm512_fmadd_ph(_s, _a, _b); __m512 _s2; _s2 = _mm512_cvtxph_ps(_mm512_cvtxps_ph(_s2)); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX512_FP16)

        unset(CMAKE_REQUIRED_FLAGS)
    elseif(CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND CMAKE_CXX_SIMULATE_ID MATCHES "MSVC" AND CMAKE_CXX_COMPILER_FRONTEND_VARIANT MATCHES "MSVC")
        check_cxx_compiler_flag("-mrecip=none" NCNN_COMPILER_SUPPORT_X86_RECIP_NONE)

        check_cxx_compiler_flag("/arch:AVX" NCNN_COMPILER_SUPPORT_X86_AVX)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX -mfma -mf16c")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256 _s, _a, _b; _s = _mm256_fmadd_ps(_a, _b, _s); return 0; }" NCNN_COMPILER_SUPPORT_X86_FMA)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX -mxop")
        check_cxx_source_compiles("#include <x86intrin.h>\nint main() { __m128 _s, _a, _b; _s = _mm_maddd_epi16(_a, _b, _s); return 0; }" NCNN_COMPILER_SUPPORT_X86_XOP)

        check_cxx_compiler_flag("/arch:AVX -mf16c" NCNN_COMPILER_SUPPORT_X86_F16C)
        check_cxx_compiler_flag("/arch:AVX2 -mfma -mf16c" NCNN_COMPILER_SUPPORT_X86_AVX2)
        check_cxx_compiler_flag("/arch:AVX512 -mfma -mf16c -mavx512cd -mavx512bw -mavx512dq -mavx512vl" NCNN_COMPILER_SUPPORT_X86_AVX512)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX2 -mfma -mf16c -mavxvnni")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256i _s, _a, _b; _s = _mm256_dpwssd_avx_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_VNNI)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX2 -mfma -mf16c -mavxvnni -mavxvnniint8")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256i _s, _a, _b; _s = _mm256_dpbssd_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_VNNI_INT8)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX2 -mfma -mf16c -mavxvnni -mavxvnniint16")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256i _s, _a, _b; _s = _mm256_dpwsud_avx_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_VNNI_INT16)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX2 -mfma -mf16c -mavxneconvert")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256 _a; __m128bh _s = _mm256_cvtneps_avx_pbh(_a); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_NE_CONVERT)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX512 -mfma -mf16c -mavx512cd -mavx512bw -mavx512dq -mavx512vl -mavx512vnni")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m512i _s, _a, _b; _s = _mm512_dpwssd_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX512_VNNI)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX512 -mfma -mf16c -mavx512cd -mavx512bw -mavx512dq -mavx512vl -mavx512bf16")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256bh _s; __m512bh _a, _b; _s = _mm512_cvtneps_pbh(_mm512_dpbf16_ps(_mm512_cvtpbh_ps(_s), _a, _b)); return 0; }\n__m512i t(__m512 a) { __m256i _a = (__m256i)_mm512_cvtneps_pbh(a); return _mm512_inserti32x8(_mm512_castsi256_si512(_a), _a, 1); }" NCNN_COMPILER_SUPPORT_X86_AVX512_BF16)

        set(CMAKE_REQUIRED_FLAGS "/arch:AVX512 -mfma -mf16c -mavx512cd -mavx512bw -mavx512dq -mavx512vl -mavx512fp16")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m512h _s, _a, _b; _s = _mm512_fmadd_ph(_s, _a, _b); __m512 _s2; _s2 = _mm512_cvtxph_ps(_mm512_cvtxps_ph(_s2)); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX512_FP16)

        unset(CMAKE_REQUIRED_FLAGS)
    else()
        check_cxx_compiler_flag("-mrecip=none" NCNN_COMPILER_SUPPORT_X86_RECIP_NONE)

        check_cxx_compiler_flag("-mavx" NCNN_COMPILER_SUPPORT_X86_AVX)

        set(CMAKE_REQUIRED_FLAGS "-mfma -mf16c")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256 _s, _a, _b; _s = _mm256_fmadd_ps(_a, _b, _s); return 0; }" NCNN_COMPILER_SUPPORT_X86_FMA)

        check_cxx_compiler_flag("-mxop" NCNN_COMPILER_SUPPORT_X86_XOP)
        check_cxx_compiler_flag("-mf16c" NCNN_COMPILER_SUPPORT_X86_F16C)
        check_cxx_compiler_flag("-mfma -mf16c -mavx2" NCNN_COMPILER_SUPPORT_X86_AVX2)
        check_cxx_compiler_flag("-mfma -mf16c -mavx512f -mavx512cd -mavx512bw -mavx512dq -mavx512vl" NCNN_COMPILER_SUPPORT_X86_AVX512)

        set(CMAKE_REQUIRED_FLAGS "-mfma -mf16c -mavx2 -mavxvnni")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256i _s, _a, _b; _s = _mm256_dpwssd_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_VNNI)

        set(CMAKE_REQUIRED_FLAGS "-mfma -mf16c -mavx2 -mavxvnni -mavxvnniint8")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256i _s, _a, _b; _s = _mm256_dpbssd_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_VNNI_INT8)

        set(CMAKE_REQUIRED_FLAGS "-mfma -mf16c -mavx2 -mavxvnni -mavxvnniint16")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256i _s, _a, _b; _s = _mm256_dpwsud_avx_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_VNNI_INT16)

        set(CMAKE_REQUIRED_FLAGS "-mfma -mf16c -mavx2 -mavxneconvert")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256 _a; __m128bh _s = _mm256_cvtneps_avx_pbh(_a); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX_NE_CONVERT)

        set(CMAKE_REQUIRED_FLAGS "-mfma -mf16c -mavx512f -mavx512cd -mavx512bw -mavx512dq -mavx512vl -mavx512vnni")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m512i _s, _a, _b; _s = _mm512_dpwssd_epi32(_s, _a, _b); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX512_VNNI)

        set(CMAKE_REQUIRED_FLAGS "-mfma -mf16c -mavx512f -mavx512cd -mavx512bw -mavx512dq -mavx512vl -mavx512bf16")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m256bh _s; __m512bh _a, _b; _s = _mm512_cvtneps_pbh(_mm512_dpbf16_ps(_mm512_cvtpbh_ps(_s), _a, _b)); return 0; }\n__m512i t(__m512 a) { __m256i _a = (__m256i)_mm512_cvtneps_pbh(a); return _mm512_inserti32x8(_mm512_castsi256_si512(_a), _a, 1); }" NCNN_COMPILER_SUPPORT_X86_AVX512_BF16)

        set(CMAKE_REQUIRED_FLAGS "-mfma -mf16c -mavx512f -mavx512cd -mavx512bw -mavx512dq -mavx512vl -mavx512fp16")
        check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m512h _s, _a, _b; _s = _mm512_fmadd_ph(_s, _a, _b); __m512 _s2; _s2 = _mm512_cvtxph_ps(_mm512_cvtxps_ph(_s2)); return 0; }" NCNN_COMPILER_SUPPORT_X86_AVX512_FP16)

        unset(CMAKE_REQUIRED_FLAGS)
    endif()

    if(NOT CMAKE_SYSTEM_NAME MATCHES "Emscripten|WASI" AND NCNN_COMPILER_SUPPORT_X86_AVX)
        option(NCNN_AVX "optimize x86 platform with avx extension" ON)
        if(NCNN_COMPILER_SUPPORT_X86_FMA)
            if(NCNN_AVX)
                option(NCNN_FMA "optimize x86 platform with fma extension" ON)
            endif()
        else()
            message(WARNING "The compiler does not support fma extension. NCNN_FMA will be OFF.")
        endif()
        if(NCNN_COMPILER_SUPPORT_X86_XOP)
            if(NCNN_AVX)
                option(NCNN_XOP "optimize x86 platform with xop extension" ON)
            endif()
        else()
            message(WARNING "The compiler does not support xop extension. NCNN_XOP will be OFF.")
        endif()
        if(NCNN_COMPILER_SUPPORT_X86_F16C)
            if(NCNN_AVX)
                option(NCNN_F16C "optimize x86 platform with f16c extension" ON)
            endif()
        else()
            message(WARNING "The compiler does not support f16c extension. NCNN_F16C will be OFF.")
        endif()
        if(NCNN_COMPILER_SUPPORT_X86_AVX2)
            if(NCNN_AVX)
                option(NCNN_AVX2 "optimize x86 platform with avx2 extension" ON)
            endif()
            if(NCNN_COMPILER_SUPPORT_X86_AVX_VNNI)
                if(NCNN_AVX2)
                    option(NCNN_AVXVNNI "optimize x86 platform with avx vnni extension" ON)
                endif()
                if(NCNN_COMPILER_SUPPORT_X86_AVX_VNNI_INT8)
                    if(NCNN_AVXVNNI)
                        option(NCNN_AVXVNNIINT8 "optimize x86 platform with avx vnni int8 extension" ON)
                    endif()
                else()
                    message(WARNING "The compiler does not support avx vnni int8 extension. NCNN_AVXVNNIINT8 will be OFF.")
                endif()
                if(NCNN_COMPILER_SUPPORT_X86_AVX_VNNI_INT16)
                    if(NCNN_AVXVNNI)
                        option(NCNN_AVXVNNIINT16 "optimize x86 platform with avx vnni int16 extension" ON)
                    endif()
                else()
                    message(WARNING "The compiler does not support avx vnni int16 extension. NCNN_AVXVNNIINT16 will be OFF.")
                endif()
            else()
                message(WARNING "The compiler does not support avx vnni extension. NCNN_AVXVNNI will be OFF.")
            endif()
            if(NCNN_COMPILER_SUPPORT_X86_AVX_NE_CONVERT)
                if(NCNN_AVX2)
                    option(NCNN_AVXNECONVERT "optimize x86 platform with avx ne convert extension" ON)
                endif()
            else()
                message(WARNING "The compiler does not support avx ne convert extension. NCNN_AVXNECONVERT will be OFF.")
            endif()
            if(NCNN_COMPILER_SUPPORT_X86_AVX512)
                if(NCNN_AVX2)
                    option(NCNN_AVX512 "optimize x86 platform with avx512 extension" ON)
                endif()
                if(NCNN_COMPILER_SUPPORT_X86_AVX512_VNNI)
                    if(NCNN_AVX512)
                        option(NCNN_AVX512VNNI "optimize x86 platform with avx512 vnni extension" ON)
                    endif()
                else()
                    message(WARNING "The compiler does not support avx512 vnni extension. NCNN_AVX512VNNI will be OFF.")
                endif()
                if(NCNN_COMPILER_SUPPORT_X86_AVX512_BF16)
                    if(NCNN_AVX512)
                        option(NCNN_AVX512BF16 "optimize x86 platform with avx512 bf16 extension" ON)
                    endif()
                else()
                    message(WARNING "The compiler does not support avx512 bf16 extension. NCNN_AVX512BF16 will be OFF.")
                endif()
                if(NCNN_COMPILER_SUPPORT_X86_AVX512_FP16)
                    if(NCNN_AVX512)
                        option(NCNN_AVX512FP16 "optimize x86 platform with avx512 fp16 extension" ON)
                    endif()
                else()
                    message(WARNING "The compiler does not support avx512 fp16 extension. NCNN_AVX512FP16 will be OFF.")
                endif()
            else()
                message(WARNING "The compiler does not support avx512 extension. NCNN_AVX512 will be OFF.")
            endif()
        else()
            message(WARNING "The compiler does not support avx2 extension. NCNN_AVX2 will be OFF.")
        endif()
    else()
        message(WARNING "The compiler does not support avx extension. NCNN_AVX will be OFF.")
    endif()
endif()

if(NCNN_TARGET_ILP32)
    message(STATUS "Target arch: ${NCNN_TARGET_ARCH} 64bit ilp32")
elseif(CMAKE_SIZEOF_VOID_P EQUAL 8)
    message(STATUS "Target arch: ${NCNN_TARGET_ARCH} 64bit")
else()
    message(STATUS "Target arch: ${NCNN_TARGET_ARCH} 32bit")
endif()

##############################################

# set cmake default folder name
set_property(GLOBAL PROPERTY USE_FOLDERS ON)
set_property(GLOBAL PROPERTY PREDEFINED_TARGETS_FOLDER "cmake")

if(CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -s FORCE_FILESYSTEM=1 -s INITIAL_MEMORY=256MB -s EXIT_RUNTIME=1")
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -s FORCE_FILESYSTEM=1 -s INITIAL_MEMORY=256MB -s EXIT_RUNTIME=1")
    set(CMAKE_EXECUTBLE_LINKER_FLAGS "${CMAKE_EXECUTBLE_LINKER_FLAGS} -s FORCE_FILESYSTEM=1 -s INITIAL_MEMORY=256MB -s EXIT_RUNTIME=1")

    if(NCNN_OPENMP AND NCNN_SIMPLEOMP)
        # TODO better flags for emscripten
        # node --experimental-wasm-threads xxx.js
        set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -s USE_PTHREADS=1 -s PTHREAD_POOL_SIZE=15")
        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -s USE_PTHREADS=1 -s PTHREAD_POOL_SIZE=15")
        set(CMAKE_EXECUTBLE_LINKER_FLAGS "${CMAKE_EXECUTBLE_LINKER_FLAGS} -s USE_PTHREADS=1 -s PTHREAD_POOL_SIZE=15")
    endif()
endif()

if(ANDROID_NDK_MAJOR AND (ANDROID_NDK_MAJOR GREATER_EQUAL 27))
    # llvm 18 in ndk-27 introduce __libcpp_verbose_abort for assertion output
    # define empty body for fixing linking issue with old ndk
    add_definitions("-D_LIBCPP_VERBOSE_ABORT\\(format,args...\\)=")
endif()

if(NCNN_VULKAN)
    if(NCNN_SYSTEM_GLSLANG)
        find_package(Threads)
        find_package(glslang QUIET)
        if(glslang_FOUND)
            add_library(glslang ALIAS glslang::glslang)
            add_library(SPIRV ALIAS glslang::SPIRV)
        else()
            set(GLSLANG_TARGET_DIR "GLSLANG-NOTFOUND" CACHE PATH "Absolute path to glslangTargets.cmake directory")
            if(NOT GLSLANG_TARGET_DIR AND NOT DEFINED ENV{GLSLANG_TARGET_DIR})
                message(WARNING "set glslang_DIR to glslang-config.cmake directory for using system glslang.")
                message(WARNING "GLSLANG_TARGET_DIR must be defined! NCNN_SYSTEM_GLSLANG will be turned off.")
                set(NCNN_SYSTEM_GLSLANG OFF)
            else()
                include("${GLSLANG_TARGET_DIR}/OSDependentTargets.cmake")
                include("${GLSLANG_TARGET_DIR}/OGLCompilerTargets.cmake")
                if(EXISTS "${GLSLANG_TARGET_DIR}/HLSLTargets.cmake")
                    # hlsl support can be optional
                    include("${GLSLANG_TARGET_DIR}/HLSLTargets.cmake")
                endif()
                include("${GLSLANG_TARGET_DIR}/glslangTargets.cmake")
                include("${GLSLANG_TARGET_DIR}/SPIRVTargets.cmake")
            endif()
        endif()

        if (TARGET glslang AND TARGET SPIRV)
            get_property(glslang_location TARGET glslang PROPERTY LOCATION)
            get_property(SPIRV_location TARGET SPIRV PROPERTY LOCATION)
            message(STATUS "Found glslang: ${glslang_location} (found version \"${glslang_VERSION}\")")
            message(STATUS "Found SPIRV: ${SPIRV_location} (found version \"${glslang_VERSION}\")")
        else()
            message(WARNING "glslang or SPIRV target not found! NCNN_SYSTEM_GLSLANG will be turned off.")
            set(NCNN_SYSTEM_GLSLANG OFF)
        endif()
    endif()

    if(NOT NCNN_SYSTEM_GLSLANG)
        if(NOT EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/glslang/CMakeLists.txt")
            message(FATAL_ERROR "The submodules were not downloaded! Please update submodules with \"git submodule update --init\" and try again.")
        else()
            # glslang requires c++11
            set(CMAKE_CXX_STANDARD 11)

            # remove ostream usage in glslang for better libcpp abi compatibility
            include(cmake/glslang_drop_ostream.cmake)
            glslang_drop_ostream(${CMAKE_CURRENT_LIST_DIR}/glslang)

            option(BUILD_EXTERNAL "" OFF)
            option(ENABLE_SPVREMAPPER "" OFF)
            option(ENABLE_GLSLANG_BINARIES "" OFF)
            option(ENABLE_HLSL "" OFF)
            option(ENABLE_RTTI "" OFF)
            option(ENABLE_EXCEPTIONS "" OFF)
            option(ENABLE_OPT "" OFF)
            option(ENABLE_PCH "" OFF)
            option(ENABLE_CTEST "" OFF)
            if(NCNN_SHARED_LIB)
                option(SKIP_GLSLANG_INSTALL "" ON)
            endif()
            add_subdirectory(glslang)
            if(NCNN_SHARED_LIB)
                if(CMAKE_CXX_COMPILER_ID MATCHES "GNU" OR (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND NOT CMAKE_CXX_COMPILER_FRONTEND_VARIANT MATCHES "MSVC"))
                    target_compile_options(glslang PRIVATE -fvisibility=hidden -fvisibility-inlines-hidden)
                    target_compile_options(OGLCompiler PRIVATE -fvisibility=hidden -fvisibility-inlines-hidden)
                    target_compile_options(OSDependent PRIVATE -fvisibility=hidden -fvisibility-inlines-hidden)
                    target_compile_options(SPIRV PRIVATE -fvisibility=hidden -fvisibility-inlines-hidden)
                endif()
                if(NCNN_ENABLE_LTO)
                    set_target_properties(glslang PROPERTIES INTERPROCEDURAL_OPTIMIZATION ON)
                    set_target_properties(OGLCompiler PROPERTIES INTERPROCEDURAL_OPTIMIZATION ON)
                    set_target_properties(OSDependent PROPERTIES INTERPROCEDURAL_OPTIMIZATION ON)
                    set_target_properties(SPIRV PROPERTIES INTERPROCEDURAL_OPTIMIZATION ON)
                endif()
            endif()
        endif()
    endif()
endif()

add_subdirectory(src)
if(NCNN_BUILD_BENCHMARK)
    add_subdirectory(benchmark)
endif()
if(NCNN_BUILD_EXAMPLES)
    add_subdirectory(examples)
endif()
if(NCNN_BUILD_TOOLS)
    add_subdirectory(tools)
endif()
if(NCNN_BUILD_TESTS)
    enable_testing()
    add_subdirectory(tests)
endif()
if(NCNN_PYTHON)
    add_subdirectory(python)
endif()