CMakeCompilers.txt

include(CheckCXXCompilerFlag)

option(VECTOR_ENGINE "Vector Engine to be used: x86 => [AVX512|AVX2|SSE|SERIAL]; ARM => [NEON|SERIAL]" OFF)
option(NTT_USE_NOISE_CACHE "Use a Noise cache => [ON|OFF]" OFF)
option(OT_TEST "Test OTs (ON) or test ROTs (OFF)" OFF)
option(OT_ROTTED_TEST "Test ROTTED OTs (ON) or test ROTs (OFF)" OFF)

if (CMAKE_SYSTEM_PROCESSOR MATCHES "(x86)|(X86)|(amd64)|(AMD64)")
    set (X86 TRUE)
    message(STATUS "[RLWEOT] Detected x86 arch")
else()
    set (X86 FALSE)
    if (CMAKE_SYSTEM_PROCESSOR MATCHES "(arm64)|(ARM64)")
        set (ARM64 TRUE)
        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mfpu=neon -ftree-vectorize -flax-vector-conversions")
        message(STATUS "[RLWEOT] Detected ARM64 arch")
    elseif (CMAKE_SYSTEM_PROCESSOR MATCHES "(arm)|(ARM)")
        set (ARM TRUE)
        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mfpu=neon -ftree-vectorize -flax-vector-conversions")
        message(STATUS "[RLWEOT] Detected ARM arch")
    else()
        set (ARM FALSE)
        set (ARM64 FALSE)
        message(FATAL_ERROR "Unknown arch")
    endif()
endif()

if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=native")
endif()

if (X86 AND (VECTOR_ENGINE STREQUAL "OFF"))
    check_cxx_source_compiles("#include <immintrin.h>\nint main() { __m512i avx_2p  = _mm512_set1_epi16(16 << 1); __m512i avx_t0  = _mm512_add_epi16(avx_2p, avx_2p); return 0;}" NFLLIB_USE_AVX512)
    check_cxx_source_compiles("#include <immintrin.h>\nint main() { return 0;}" NFLLIB_USE_AVX)
    check_cxx_source_compiles("#include <pmmintrin.h>\nint main() { return 0;}" NFLLIB_USE_SSE)
elseif ((ARM OR ARM64) AND (VECTOR_ENGINE STREQUAL "OFF"))
    check_cxx_source_compiles("#include <arm_neon.h>\nint main() { return 0;}" NFLLIB_USE_NEON)
else()
    message(STATUS "[RLWEOT] Disabling vector engine auto detection. User specified vector engine as ${VECTOR_ENGINE}")
endif()

if(NFLLIB_USE_AVX512 OR (VECTOR_ENGINE STREQUAL "AVX512"))
  message(STATUS "[RLWEOT] Using AVX512 vector engine")
  add_definitions(-DNTT_AVX512)
  add_definitions(-DNFL_OPTIMIZED)
elseif(NFLLIB_USE_AVX OR (VECTOR_ENGINE STREQUAL "AVX2"))
  message(STATUS "[RLWEOT] Using AVX vector engine")
  add_definitions(-DNTT_AVX2)
  add_definitions(-DNFL_OPTIMIZED)
elseif(NFLLIB_USE_SSE OR (VECTOR_ENGINE STREQUAL "SSE"))
  message(STATUS "[RLWEOT] Using SSE vector engine")
  add_definitions(-DNTT_SSE)
  add_definitions(-DNFL_OPTIMIZED)
elseif(NFLLIB_USE_NEON OR (VECTOR_ENGINE STREQUAL "NEON"))
  message(STATUS "[RLWEOT] Using NEON vector engine")
  add_definitions(-DNTT_NEON)
  add_definitions(-DNFL_OPTIMIZED)
elseif(VECTOR_ENGINE STREQUAL "SERIAL")
  message(STATUS "[RLWEOT] Using Serial implementation (vector engine disabled)")
endif()

if (NTT_USE_NOISE_CACHE STREQUAL "ON")
    add_definitions(-DNTT_USE_NOISE_CACHE)
endif()

if (OT_TEST STREQUAL "ON")
    add_definitions(-DOT_TEST)
endif()

if (OT_ROTTED_TEST STREQUAL "ON")
    add_definitions(-DOT_ROTTED_TEST)
endif()

# C++11 support
CHECK_CXX_COMPILER_FLAG(-std=c++11 COMPILER_SUPPORTS_CXX11)
if(COMPILER_SUPPORTS_CXX11)
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
else()
    CHECK_CXX_COMPILER_FLAG(-std=c++0x COMPILER_SUPPORTS_CXX0X)
    if(COMPILER_SUPPORTS_CXX0X)
        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x")
    else()
        message(STATUS "The compiler ${CMAKE_CXX_COMPILER} has no C++11 support. Please use a different C++ compiler.")
    endif()
endif()

# optimization flags support
if(CMAKE_BUILD_TYPE MATCHES Release)
    message(STATUS "Building Release w/ ${CMAKE_CXX_COMPILER_ID}")
	set(CMAKE_CXX_FLAGS_RELEASE "-O3 -g3 -ftree-vectorize")

    if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
        foreach(FLAG -march=native -mtune=native -funroll-loops)
            string(REGEX REPLACE -= _ FLAG_ID ${FLAG})
            string(TOUPPER ${FLAG_ID} FLAG_ID)
            CHECK_CXX_COMPILER_FLAG(${FLAG} COMPILER_SUPPORTS${FLAG_ID})
            set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} ${FLAG}")
        endforeach()
    else()
        foreach(FLAG -funroll-loops)
            string(REGEX REPLACE -= _ FLAG_ID ${FLAG})
            string(TOUPPER ${FLAG_ID} FLAG_ID)
            CHECK_CXX_COMPILER_FLAG(${FLAG} COMPILER_SUPPORTS${FLAG_ID})
            set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} ${FLAG}")
        endforeach()
    endif()
else()
    add_definitions(-DCHECK_STRICTMOD)
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g")
endif()

#if(APPLE)
#   set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -Wa,-q")
#endif()