diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8bbd04a0f..deac9bae7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -421,8 +421,8 @@ if(CMAKE_COMPILER_IS_GNUCXX)
         "${CMAKE_CXX_FLAGS} -O0 -fno-omit-frame-pointer -fno-inline")
     elseif (ENABLE_SIMD)
       if (X86 OR X86_64)
-        set(CMAKE_C_FLAGS_RELEASE "-O3 -msse2 -mfpmath=sse")
-        set(CMAKE_CXX_FLAGS_RELEASE "-O3 -msse2 -mfpmath=sse")
+        set(CMAKE_C_FLAGS_RELEASE "-O3 -msse2 -mfpmath=sse -ftree-vectorize -ftree-slp-vectorize")
+        set(CMAKE_CXX_FLAGS_RELEASE "-O3 -msse2 -mfpmath=sse -ftree-vectorize -ftree-slp-vectorize")
       endif()
     endif()
 endif(CMAKE_COMPILER_IS_GNUCXX)
@@ -446,7 +446,8 @@ if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "Ap
 
     if (ENABLE_SIMD)
       if (X86 OR X86_64)
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -msse3 -mfpmath=sse")
+        set(CMAKE_C_FLAGS_RELEASE "-O3 -msse2 -mfpmath=sse -ftree-vectorize -ftree-slp-vectorize")
+        set(CMAKE_CXX_FLAGS_RELEASE "-O3 -msse2 -mfpmath=sse -ftree-vectorize -ftree-slp-vectorize")
       endif()
     endif()