Without seeing your code, it's impossible to be sure, but I guess that you have some functions that use intrinsics, and, specifically pmovmskb, which is an instruction that is not implemented on KNC.
You can see this by looking at the online version of the intrinsics guide https://software.intel.com/sites/landingpage/IntrinsicsGuide/#text=pmovmskb ;
The colour coding shows where the intrinsic is supported.
