about SIMD code

[llodds1]

Just write some SIMD code instead of making the compiler generate the SIMD code automatically, but how do I enable the icc compiler to compile with the code?

[Bernard]

Write inline SSE assembly and compile it with Intel compiler.

[Thomas_W_Intel]

If you don't want to go down the path of writing in assembly language, there is also same kind of wrapper called "intrinsics" that looks and feels like a function call but are translated directly to assembly. A description is given in this article. For a recent example with AVX2, you might be interested in my blog.