
# Check if SSE instructions are available on the machine where 
# the project is compiled.

IF (CMAKE_SYSTEM_NAME MATCHES "Linux")
    EXEC_PROGRAM(cat ARGS "/proc/cpuinfo" OUTPUT_VARIABLE CPUINFO)

    STRING(REGEX REPLACE "^.*(sse2).*$" "\\1" SSE_THERE ${CPUINFO})
    STRING(COMPARE EQUAL "sse2" "${SSE_THERE}" SSE2_TRUE)
    IF (SSE2_TRUE)
        set(SSE2_FOUND true BOOL "SSE2 available on host")
    ELSE (SSE2_TRUE)
        set(SSE2_FOUND false BOOL "SSE2 available on host")
    ENDIF (SSE2_TRUE)

    # /proc/cpuinfo apparently omits sse3 :(
    STRING(REGEX REPLACE "^.*[^s](sse3).*$" "\\1" SSE_THERE ${CPUINFO})
    STRING(COMPARE EQUAL "sse3" "${SSE_THERE}" SSE3_TRUE)
    IF (NOT SSE3_TRUE)
        STRING(REGEX REPLACE "^.*(T2300).*$" "\\1" SSE_THERE ${CPUINFO})
        STRING(COMPARE EQUAL "T2300" "${SSE_THERE}" SSE3_TRUE)
    ENDIF (NOT SSE3_TRUE)

    STRING(REGEX REPLACE "^.*(ssse3).*$" "\\1" SSE_THERE ${CPUINFO})
    STRING(COMPARE EQUAL "ssse3" "${SSE_THERE}" SSSE3_TRUE)
    IF (SSE3_TRUE OR SSSE3_TRUE)
        set(SSE3_FOUND true BOOL "SSE3 available on host")
    ELSE (SSE3_TRUE OR SSSE3_TRUE)
        set(SSE3_FOUND false BOOL "SSE3 available on host")
    ENDIF (SSE3_TRUE OR SSSE3_TRUE)
    IF (SSSE3_TRUE)
        set(SSSE3_FOUND true BOOL "SSSE3 available on host")
    ELSE (SSSE3_TRUE)
        set(SSSE3_FOUND false BOOL "SSSE3 available on host")
    ENDIF (SSSE3_TRUE)

    STRING(REGEX REPLACE "^.*(sse4_1).*$" "\\1" SSE_THERE ${CPUINFO})
    STRING(COMPARE EQUAL "sse4_1" "${SSE_THERE}" SSE41_TRUE)
    IF (SSE41_TRUE)
        set(SSE4_1_FOUND true BOOL "SSE4.1 available on host")
    ELSE (SSE41_TRUE)
        set(SSE4_1_FOUND false BOOL "SSE4.1 available on host")
    ENDIF (SSE41_TRUE)

    STRING(REGEX REPLACE "^.*(sse4_2).*$" "\\1" SSE_THERE ${CPUINFO})
    STRING(COMPARE EQUAL "sse4_2" "${SSE_THERE}" SSE42_TRUE)
    IF (SSE42_TRUE)
        set(SSE4_2_FOUND true BOOL "SSE4.2 available on host")
    ELSE (SSE42_TRUE)
        set(SSE4_2_FOUND false BOOL "SSE4.2 available on host")
    ENDIF (SSE42_TRUE)

ELSEIF (CMAKE_SYSTEM_NAME MATCHES "Darwin")
    EXEC_PROGRAM("/usr/sbin/sysctl -n machdep.cpu.features" OUTPUT_VARIABLE
            CPUINFO)

    STRING(REGEX REPLACE "^.*[^S](SSE2).*$" "\\1" SSE_THERE ${CPUINFO})
    STRING(COMPARE EQUAL "SSE2" "${SSE_THERE}" SSE2_TRUE)
    IF (SSE2_TRUE)
        set(SSE2_FOUND true BOOL "SSE2 available on host")
    ELSE (SSE2_TRUE)
        set(SSE2_FOUND false BOOL "SSE2 available on host")
    ENDIF (SSE2_TRUE)

    STRING(REGEX REPLACE "^.*[^S](SSE3).*$" "\\1" SSE_THERE ${CPUINFO})
    STRING(COMPARE EQUAL "SSE3" "${SSE_THERE}" SSE3_TRUE)
    IF (SSE3_TRUE)
        set(SSE3_FOUND true BOOL "SSE3 available on host")
    ELSE (SSE3_TRUE)
        set(SSE3_FOUND false BOOL "SSE3 available on host")
    ENDIF (SSE3_TRUE)

    STRING(REGEX REPLACE "^.*(SSSE3).*$" "\\1" SSE_THERE ${CPUINFO})
    STRING(COMPARE EQUAL "SSSE3" "${SSE_THERE}" SSSE3_TRUE)
    IF (SSSE3_TRUE)
        set(SSSE3_FOUND true BOOL "SSSE3 available on host")
    ELSE (SSSE3_TRUE)
        set(SSSE3_FOUND false BOOL "SSSE3 available on host")
    ENDIF (SSSE3_TRUE)

    STRING(REGEX REPLACE "^.*(SSE4.1).*$" "\\1" SSE_THERE ${CPUINFO})
    STRING(COMPARE EQUAL "SSE4.1" "${SSE_THERE}" SSE41_TRUE)
    IF (SSE41_TRUE)
        set(SSE4_1_FOUND true BOOL "SSE4.1 available on host")
    ELSE (SSE41_TRUE)
        set(SSE4_1_FOUND false BOOL "SSE4.1 available on host")
    ENDIF (SSE41_TRUE)

    STRING(REGEX REPLACE "^.*(SSE4.2).*$" "\\1" SSE_THERE ${CPUINFO})
    STRING(COMPARE EQUAL "SSE4.2" "${SSE_THERE}" SSE42_TRUE)
    IF (SSE42_TRUE)
        set(SSE4_2_FOUND true BOOL "SSE4.2 available on host")
    ELSE (SSE42_TRUE)
        set(SSE4_2_FOUND false BOOL "SSE4.2 available on host")
    ENDIF (SSE42_TRUE)
ENDIF (CMAKE_SYSTEM_NAME MATCHES "Linux")

if (NOT SSE2_FOUND)
    MESSAGE(STATUS "Could not find hardware support for SSE2 on this machine.")
endif (NOT SSE2_FOUND)
if (NOT SSE3_FOUND)
    MESSAGE(STATUS "Could not find hardware support for SSE3 on this machine.")
endif (NOT SSE3_FOUND)
if (NOT SSSE3_FOUND)
    MESSAGE(STATUS "Could not find hardware support for SSSE3 on this machine.")
endif (NOT SSSE3_FOUND)
if (NOT SSE4_1_FOUND)
    MESSAGE(STATUS "Could not find hardware support for SSE4.1 on this machine.")
endif (NOT SSE4_1_FOUND)
if (NOT SSE4_2_FOUND)
    MESSAGE(STATUS "Could not find hardware support for SSE4.2 on this machine.")
endif (NOT SSE4_2_FOUND)

mark_as_advanced(SSE2_FOUND SSE3_FOUND SSSE3_FOUND SSE4_1_FOUND SSE4_2_FOUND)
