[Discuss-gnuradio] how to test sse2 support using cmake

[Kyle Zhou]

I have a block which depends on sse2. I need to tell cmake to check if the cpu 
support sse2 in order to determine if the sse2 acceleated version or a generic 
version should be used.
This should be straight forward. However, I just cannot find an example 
CMakeLists.txt to get me a quick start.
Any suggested readings? thanks
K Z