The software usually deals with abstractions whereas hardware handles implementation details of how to execute instructions.

I like the way you worded your statement @sidhikab. I would also say that depending on your point of view, the line can bend one way or the other. For example, when considering the ISPC code from Lec 4 (e.g. slide 37), we see how the ISPC compiler (software) is handling the implementation in that it transforms ISPC code (abstraction) to C+ AVX intrinsic code (implementation), all while staying at the software level. Then, there is also the viewpoint of taking the intrinsic code abstraction to actual hardware implementation.