macro(simd_fail message)
  if(REQUIRE_SIMD)
    message(FATAL_ERROR "${message}.")
  else()
    message(WARNING "${message}.  Performance will suffer.")
    set(WITH_SIMD 0 PARENT_SCOPE)
  endif()
endmacro()


###############################################################################
# x86[-64] (NASM)
###############################################################################

if(CPU_TYPE STREQUAL "x86_64" OR CPU_TYPE STREQUAL "i386")

set(CMAKE_ASM_NASM_FLAGS_DEBUG_INIT "-g")
set(CMAKE_ASM_NASM_FLAGS_RELWITHDEBINFO_INIT "-g")

# Allow the location of the NASM executable to be specified using the ASM_NASM
# environment variable.  This should happen automatically, but unfortunately
# enable_language(ASM_NASM) doesn't parse the ASM_NASM environment variable
# until after CMAKE_ASM_NASM_COMPILER has been populated with the results of
# searching for NASM or YASM in the PATH.
if(NOT DEFINED CMAKE_ASM_NASM_COMPILER AND DEFINED ENV{ASM_NASM})
  set(CMAKE_ASM_NASM_COMPILER $ENV{ASM_NASM})
endif()

if(CPU_TYPE STREQUAL "x86_64")
  if(CYGWIN)
    set(CMAKE_ASM_NASM_OBJECT_FORMAT win64)
  endif()
elseif(CPU_TYPE STREQUAL "i386")
  if(BORLAND)
    set(CMAKE_ASM_NASM_OBJECT_FORMAT obj)
  elseif(CYGWIN)
    set(CMAKE_ASM_NASM_OBJECT_FORMAT win32)
  endif()
endif()

enable_language(ASM_NASM)
message(STATUS "CMAKE_ASM_NASM_COMPILER = ${CMAKE_ASM_NASM_COMPILER}")

if(CMAKE_ASM_NASM_OBJECT_FORMAT MATCHES "macho*")
  set(CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} -DMACHO")
elseif(CMAKE_ASM_NASM_OBJECT_FORMAT MATCHES "elf*")
  set(CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} -DELF")
  set(CMAKE_ASM_NASM_DEBUG_FORMAT "dwarf2")
endif()
if(CPU_TYPE STREQUAL "x86_64")
  if(WIN32 OR CYGWIN)
    set(CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} -DWIN64")
  endif()
  set(CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} -D__x86_64__")
elseif(CPU_TYPE STREQUAL "i386")
  if(BORLAND)
    set(CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} -DOBJ32")
  elseif(WIN32 OR CYGWIN)
    set(CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} -DWIN32")
  endif()
endif()

message(STATUS "CMAKE_ASM_NASM_OBJECT_FORMAT = ${CMAKE_ASM_NASM_OBJECT_FORMAT}")

if(NOT CMAKE_ASM_NASM_OBJECT_FORMAT)
  simd_fail("SIMD extensions disabled: could not determine NASM object format")
  return()
endif()

get_filename_component(CMAKE_ASM_NASM_COMPILER_TYPE
  "${CMAKE_ASM_NASM_COMPILER}" NAME_WE)
if(CMAKE_ASM_NASM_COMPILER_TYPE MATCHES "yasm")
  foreach(var CMAKE_ASM_NASM_FLAGS_DEBUG CMAKE_ASM_NASM_FLAGS_RELWITHDEBINFO)
    if(${var} STREQUAL "-g")
      if(CMAKE_ASM_NASM_DEBUG_FORMAT)
        set_property(CACHE ${var} PROPERTY VALUE "-g ${CMAKE_ASM_NASM_DEBUG_FORMAT}")
      else()
        set_property(CACHE ${var} PROPERTY VALUE "")
      endif()
    endif()
  endforeach()
endif()

if(NOT WIN32 AND (CMAKE_POSITION_INDEPENDENT_CODE OR ENABLE_SHARED))
  set(CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} -DPIC")
endif()

string(TOUPPER ${CMAKE_BUILD_TYPE} CMAKE_BUILD_TYPE_UC)
set(EFFECTIVE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} ${CMAKE_ASM_NASM_FLAGS_${CMAKE_BUILD_TYPE_UC}}")
message(STATUS "CMAKE_ASM_NASM_FLAGS = ${EFFECTIVE_ASM_NASM_FLAGS}")

set(CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} -I\"${CMAKE_CURRENT_SOURCE_DIR}/nasm/\" -I\"${CMAKE_CURRENT_SOURCE_DIR}/${CPU_TYPE}/\"")

if(WIN32)
  set(CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} -I\"${CMAKE_CURRENT_SOURCE_DIR}/../win/\"")
  set(JSIMDCFG_INC ${CMAKE_CURRENT_SOURCE_DIR}/../win/jsimdcfg.inc)
else()
  set(GREP grep)
  if(CMAKE_SYSTEM_NAME STREQUAL "SunOS")
    set(GREP ggrep)
  endif()
  add_custom_command(OUTPUT jsimdcfg.inc
    COMMAND ${CMAKE_C_COMPILER} -E -I${CMAKE_BINARY_DIR} -I${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/jsimdcfg.inc.h | ${GREP} -E '^[\;%]|^\ %' | sed 's%_cpp_protection_%%' | sed 's@% define@%define@g' >jsimdcfg.inc)
  set(JSIMDCFG_INC ${CMAKE_CURRENT_BINARY_DIR}/jsimdcfg.inc)
  set(CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS} -I\"${CMAKE_CURRENT_BINARY_DIR}/\"")
endif()

if(CPU_TYPE STREQUAL "x86_64")
  set(SIMD_SOURCES x86_64/jsimdcpu.asm x86_64/jfdctflt-sse.asm
    x86_64/jccolor-sse2.asm x86_64/jcgray-sse2.asm x86_64/jchuff-sse2.asm
    x86_64/jcsample-sse2.asm x86_64/jdcolor-sse2.asm x86_64/jdmerge-sse2.asm
    x86_64/jdsample-sse2.asm x86_64/jfdctfst-sse2.asm x86_64/jfdctint-sse2.asm
    x86_64/jidctflt-sse2.asm x86_64/jidctfst-sse2.asm x86_64/jidctint-sse2.asm
    x86_64/jidctred-sse2.asm x86_64/jquantf-sse2.asm x86_64/jquanti-sse2.asm
    x86_64/jccolor-avx2.asm x86_64/jcgray-avx2.asm x86_64/jchuff-avx2.asm
    x86_64/jcsample-avx2.asm x86_64/jdcolor-avx2.asm x86_64/jdmerge-avx2.asm
    x86_64/jdsample-avx2.asm x86_64/jfdctfst-avx2.asm x86_64/jfdctint-avx2.asm
    x86_64/jidctint-avx2.asm x86_64/jquanti-avx2.asm)
else()
  set(SIMD_SOURCES i386/jsimdcpu.asm i386/jfdctflt-3dn.asm
    i386/jidctflt-3dn.asm i386/jquant-3dn.asm
    i386/jccolor-mmx.asm i386/jcgray-mmx.asm i386/jcsample-mmx.asm
    i386/jdcolor-mmx.asm i386/jdmerge-mmx.asm i386/jdsample-mmx.asm
    i386/jfdctfst-mmx.asm i386/jfdctint-mmx.asm i386/jidctfst-mmx.asm
    i386/jidctint-mmx.asm i386/jidctred-mmx.asm i386/jquant-mmx.asm
    i386/jfdctflt-sse.asm i386/jidctflt-sse.asm i386/jquant-sse.asm
    i386/jccolor-sse2.asm i386/jcgray-sse2.asm i386/jchuff-sse2.asm
    i386/jcsample-sse2.asm i386/jdcolor-sse2.asm i386/jdmerge-sse2.asm
    i386/jdsample-sse2.asm i386/jfdctfst-sse2.asm i386/jfdctint-sse2.asm
    i386/jidctflt-sse2.asm i386/jidctfst-sse2.asm i386/jidctint-sse2.asm
    i386/jidctred-sse2.asm i386/jquantf-sse2.asm i386/jquanti-sse2.asm
    i386/jccolor-avx2.asm i386/jcgray-avx2.asm i386/jchuff-avx2.asm
    i386/jcsample-avx2.asm i386/jdcolor-avx2.asm i386/jdmerge-avx2.asm
    i386/jdsample-avx2.asm i386/jfdctint-avx2.asm i386/jidctint-avx2.asm
    i386/jquanti-avx2.asm)
endif()

if(MSVC_IDE)
  set(OBJDIR "${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}")
  string(REGEX REPLACE " " ";" CMAKE_ASM_NASM_FLAGS "${CMAKE_ASM_NASM_FLAGS}")
endif()

file(GLOB INC_FILES nasm/*.inc)

foreach(file ${SIMD_SOURCES})
  set(OBJECT_DEPENDS "")
  if(${file} MATCHES jccolor)
    string(REGEX REPLACE "jccolor" "jccolext" DEPFILE ${file})
    set(OBJECT_DEPENDS ${OBJECT_DEPENDS}
      ${CMAKE_CURRENT_SOURCE_DIR}/${DEPFILE})
  endif()
  if(${file} MATCHES jcgray)
    string(REGEX REPLACE "jcgray" "jcgryext" DEPFILE ${file})
    set(OBJECT_DEPENDS ${OBJECT_DEPENDS}
      ${CMAKE_CURRENT_SOURCE_DIR}/${DEPFILE})
  endif()
  if(${file} MATCHES jdcolor)
    string(REGEX REPLACE "jdcolor" "jdcolext" DEPFILE ${file})
    set(OBJECT_DEPENDS ${OBJECT_DEPENDS}
      ${CMAKE_CURRENT_SOURCE_DIR}/${DEPFILE})
  endif()
  if(${file} MATCHES jdmerge)
    string(REGEX REPLACE "jdmerge" "jdmrgext" DEPFILE ${file})
    set(OBJECT_DEPENDS ${OBJECT_DEPENDS}
      ${CMAKE_CURRENT_SOURCE_DIR}/${DEPFILE})
  endif()
  set(OBJECT_DEPENDS ${OBJECT_DEPENDS} ${INC_FILES} ${JSIMDCFG_INC})
  if(MSVC_IDE)
    # The CMake Visual Studio generators do not work properly with the ASM_NASM
    # language, so we have to go rogue here and use a custom command like we
    # did in prior versions of libjpeg-turbo.  (This is why we can't have nice
    # things.)
    string(REGEX REPLACE "${CPU_TYPE}/" "" filename ${file})
    set(SIMD_OBJ ${OBJDIR}/${filename}.obj)
    add_custom_command(OUTPUT ${SIMD_OBJ} DEPENDS ${file} ${OBJECT_DEPENDS}
      COMMAND ${CMAKE_ASM_NASM_COMPILER} -f${CMAKE_ASM_NASM_OBJECT_FORMAT}
        ${CMAKE_ASM_NASM_FLAGS} ${CMAKE_CURRENT_SOURCE_DIR}/${file}
        -o${SIMD_OBJ})
    set(SIMD_OBJS ${SIMD_OBJS} ${SIMD_OBJ})
  else()
    set_source_files_properties(${file} PROPERTIES OBJECT_DEPENDS
      "${OBJECT_DEPENDS}")
  endif()
endforeach()

if(MSVC_IDE)
  set(SIMD_OBJS ${SIMD_OBJS} PARENT_SCOPE)
  add_library(simd OBJECT ${CPU_TYPE}/jsimd.c)
  add_custom_target(simd-objs DEPENDS ${SIMD_OBJS})
  add_dependencies(simd simd-objs)
else()
  add_library(simd OBJECT ${SIMD_SOURCES} ${CPU_TYPE}/jsimd.c)
endif()
if(NOT WIN32 AND (CMAKE_POSITION_INDEPENDENT_CODE OR ENABLE_SHARED))
  set_target_properties(simd PROPERTIES POSITION_INDEPENDENT_CODE 1)
endif()


###############################################################################
# ARM (GAS)
###############################################################################

elseif(CPU_TYPE STREQUAL "arm64" OR CPU_TYPE STREQUAL "arm")

enable_language(ASM)

set(CMAKE_ASM_FLAGS ${CMAKE_C_FLAGS}${CMAKE_ASM_FLAGS})

string(TOUPPER ${CMAKE_BUILD_TYPE} CMAKE_BUILD_TYPE_UC)
set(EFFECTIVE_ASM_FLAGS "${CMAKE_ASM_FLAGS} ${CMAKE_ASM_FLAGS_${CMAKE_BUILD_TYPE_UC}}")
message(STATUS "CMAKE_ASM_FLAGS = ${EFFECTIVE_ASM_FLAGS}")

# Test whether we need gas-preprocessor.pl
if(CPU_TYPE STREQUAL "arm")
  file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/gastest.S "
    .text
    .fpu neon
    .arch armv7a
    .object_arch armv4
    .arm
    pld [r0]
    vmovn.u16 d0, q0")
else()
  file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/gastest.S "
    .text
    MYVAR .req x0
    movi v0.16b, #100
    mov MYVAR, #100
    .unreq MYVAR")
endif()

separate_arguments(CMAKE_ASM_FLAGS_SEP UNIX_COMMAND "${CMAKE_ASM_FLAGS}")

execute_process(COMMAND ${CMAKE_ASM_COMPILER} ${CMAKE_ASM_FLAGS_SEP}
    -x assembler-with-cpp -c ${CMAKE_CURRENT_BINARY_DIR}/gastest.S
  RESULT_VARIABLE RESULT OUTPUT_VARIABLE OUTPUT ERROR_VARIABLE ERROR)
if(NOT RESULT EQUAL 0)
  message(STATUS "GAS appears to be broken.  Trying gas-preprocessor.pl ...")
  execute_process(COMMAND gas-preprocessor.pl ${CMAKE_ASM_COMPILER}
      ${CMAKE_ASM_FLAGS_SEP} -x assembler-with-cpp -c
      ${CMAKE_CURRENT_BINARY_DIR}/gastest.S
    RESULT_VARIABLE RESULT OUTPUT_VARIABLE OUTPUT ERROR_VARIABLE ERROR)
  if(NOT RESULT EQUAL 0)
    simd_fail("SIMD extensions disabled: GAS is not working properly")
    return()
  else()
    message(STATUS "Using gas-preprocessor.pl")
    configure_file(gas-preprocessor.in gas-preprocessor @ONLY)
    set(CMAKE_ASM_COMPILER ${CMAKE_CURRENT_BINARY_DIR}/gas-preprocessor)
  endif()
else()
  message(STATUS "GAS is working properly")
endif()

file(REMOVE ${CMAKE_CURRENT_BINARY_DIR}/gastest.S)

add_library(simd OBJECT ${CPU_TYPE}/jsimd_neon.S ${CPU_TYPE}/jsimd.c)

if(CMAKE_POSITION_INDEPENDENT_CODE OR ENABLE_SHARED)
  set_target_properties(simd PROPERTIES POSITION_INDEPENDENT_CODE 1)
endif()


###############################################################################
# MIPS (GAS)
###############################################################################

elseif(CPU_TYPE STREQUAL "mips")

enable_language(ASM)

string(TOUPPER ${CMAKE_BUILD_TYPE} CMAKE_BUILD_TYPE_UC)
set(EFFECTIVE_ASM_FLAGS "${CMAKE_ASM_FLAGS} ${CMAKE_ASM_FLAGS_${CMAKE_BUILD_TYPE_UC}}")
message(STATUS "CMAKE_ASM_FLAGS = ${EFFECTIVE_ASM_FLAGS}")

add_library(simd OBJECT ${CPU_TYPE}/jsimd_dspr2.S ${CPU_TYPE}/jsimd.c)

if(CMAKE_POSITION_INDEPENDENT_CODE OR ENABLE_SHARED)
  set_target_properties(simd PROPERTIES POSITION_INDEPENDENT_CODE 1)
endif()


###############################################################################
# PowerPC (Intrinsics)
###############################################################################

elseif(CPU_TYPE STREQUAL "powerpc")

set(CMAKE_REQUIRED_FLAGS -maltivec)

check_c_source_compiles("
  #include <altivec.h>
  int main(void) {
    __vector int vi = { 0, 0, 0, 0 };
    int i[4];
    vec_st(vi, 0, i);
    return i[0];
  }" HAVE_ALTIVEC)

unset(CMAKE_REQUIRED_FLAGS)

if(NOT HAVE_ALTIVEC)
  simd_fail("SIMD extensions not available for this CPU (PowerPC SPE)")
  return()
endif()

set(SIMD_SOURCES powerpc/jccolor-altivec.c powerpc/jcgray-altivec.c
  powerpc/jcsample-altivec.c powerpc/jdcolor-altivec.c
  powerpc/jdmerge-altivec.c powerpc/jdsample-altivec.c
  powerpc/jfdctfst-altivec.c powerpc/jfdctint-altivec.c
  powerpc/jidctfst-altivec.c powerpc/jidctint-altivec.c
  powerpc/jquanti-altivec.c)

set_source_files_properties(${SIMD_SOURCES} PROPERTIES
  COMPILE_FLAGS -maltivec)

add_library(simd OBJECT ${SIMD_SOURCES} powerpc/jsimd.c)

if(CMAKE_POSITION_INDEPENDENT_CODE OR ENABLE_SHARED)
  set_target_properties(simd PROPERTIES POSITION_INDEPENDENT_CODE 1)
endif()


###############################################################################
# None
###############################################################################

else()

simd_fail("SIMD extensions not available for this CPU (${CMAKE_SYSTEM_PROCESSOR})")

endif() # CPU_TYPE