[hamiltonkibbe]

I've only done a little bit with Xilinx's HLS which allows you to write "C/C++" which gets synthesized to hardware. I put C/C++ in quotes because it relies on lots of pragma directives to tell the complier enough that it can synthesize the hardware that you want, to the point of it almost being its own language entirely, There may be a few applications where this is particularly well suited, but at least for what I was doing, it was easier (and fit my mental model better... ymmv) to do it in HDL.

Edit: System Generator is pretty awesome though!