Check newest instruction set first.

Only add AVX_FLAGS.
PointCloudLibrary · Feb 11, 2021 · ed45119 · ed45119
1 parent 5658471
commit ed45119
Showing 1 changed file with 13 additions and 14 deletions.
diff --git a/cmake/pcl_find_avx.cmake b/cmake/pcl_find_avx.cmake
@@ -2,19 +2,8 @@
 # Check for the presence of AVX and figure out the flags to use for it.
 macro(PCL_CHECK_FOR_AVX)
   set(AVX_FLAGS)
-  set(AVX_DEFINITIONS)
 
   include(CheckCXXSourceRuns)
-
-  check_cxx_source_runs("
-    #include <immintrin.h>
-    int main()
-    {
-      __m256 a;
-      a = _mm256_set1_ps(0);
-      return 0;
-    }"
-  HAVE_AVX)
 
   check_cxx_source_runs("    
     #include <immintrin.h>
@@ -25,14 +14,24 @@ macro(PCL_CHECK_FOR_AVX)
       return 0;
     }"
   HAVE_AVX2)
-
+
+  if(NOT HAVE_AVX2)
+    check_cxx_source_runs("
+      #include <immintrin.h>
+      int main()
+      {
+        __m256 a;
+        a = _mm256_set1_ps(0);
+        return 0;
+      }"
+    HAVE_AVX)
+  endif()
+
   if(MSVC)
     if(HAVE_AVX)
-      string(APPEND AVX_DEFINITIONS " -D__AVX__")
       set(AVX_FLAGS "/arch:AVX")
     endif()
     if(HAVE_AVX2)
-      string(APPEND AVX_DEFINITIONS " -D__AVX2__")
       set(AVX_FLAGS "/arch:AVX2")
     endif()
   endif()