# 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 "^.*(ssse3).*$" "\\1" SSE_THERE ${CPUINFO})
   STRING(COMPARE EQUAL "ssse3" "${SSE_THERE}" SSSE3_TRUE)
   IF (SSSE3_TRUE)
      set(SSSE3_FOUND true CACHE BOOL "SSSE3 available on host")
   ELSE (SSSE3_TRUE)
      set(SSSE3_FOUND false CACHE 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 CACHE BOOL "SSE4.1 available on host")
   ELSE (SSE41_TRUE)
      set(SSE4_1_FOUND false CACHE BOOL "SSE4.1 available on host")
   ENDIF (SSE41_TRUE)
ELSEIF(CMAKE_SYSTEM_NAME MATCHES "Darwin")
   EXEC_PROGRAM("/usr/sbin/sysctl -n machdep.cpu.features" OUTPUT_VARIABLE
      CPUINFO)

   STRING(REGEX REPLACE "^.*(SSSE3).*$" "\\1" SSE_THERE ${CPUINFO})
   STRING(COMPARE EQUAL "SSSE3" "${SSE_THERE}" SSSE3_TRUE)
   IF (SSSE3_TRUE)
      set(SSSE3_FOUND true CACHE BOOL "SSSE3 available on host")
   ELSE (SSSE3_TRUE)
      set(SSSE3_FOUND false CACHE 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 CACHE BOOL "SSE4.1 available on host")
   ELSE (SSE41_TRUE)
      set(SSE4_1_FOUND false CACHE BOOL "SSE4.1 available on host")
   ENDIF (SSE41_TRUE)
ELSEIF(CMAKE_SYSTEM_NAME MATCHES "Windows")
   set(SSSE3_FOUND  false CACHE BOOL "SSSE3 available on host")
   set(SSE4_1_FOUND false CACHE BOOL "SSE4.1 available on host")
ELSE(CMAKE_SYSTEM_NAME MATCHES "Linux")
   set(SSSE3_FOUND  false CACHE BOOL "SSSE3 available on host")
   set(SSE4_1_FOUND false CACHE BOOL "SSE4.1 available on host")
ENDIF(CMAKE_SYSTEM_NAME MATCHES "Linux")

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)

mark_as_advanced(SSSE3_FOUND SSE4_1_FOUND)