Don't confuse Cygwin with a "linux emulator." In order for a Unix application to run under it, that app must be recompiled from source. There's no performance hit since you're not translating Linux executables into a Windows executable.

A test example: one can compile SDCC for Windows (as a simple console application) or for Cygwin. There's little if any difference in execution speed between the two.

For whatever reasons, the Xilinx GUI has become bloated. There are a lot of chip families to support, and a lot of things going on under the hood. And it doesn't help when the tools spew report and temporary files in your project directory. I'm sure I wasn't the only engineer bitching at Xilinx, saying, "we like to keep our HDL sources in some directory OTHER than where the place/route tool's project file lives." Older versions of the tools loved to copy the sources from your source directory to the build project directory, which is stupid and fraught with danger if you forget what file you're editing and what file is used to build the chip! So finally they added a checkbox to reference the sources instead of copying. Of course they did it wrong the first time, and put absolute paths in the project file! What happens when you check your sources out of the version-control system into some other location? Whoops, can't find 'em. Anyways, they finally got right with G-d on that one, too. Took 'em forever.

I swear, nobody at Xilinx actually designs like a real-world engineer.

If the GUI's speed (or lack thereof) drives you bonkers, you can still do the entire synthesis, map, place, route and bitgen from a command line. I use Makefiles to simplify the process. It can be tricky, because you need to sort out all of the config files necessary for the build process.

Funny, too, how all of the Xilinx FAEs say in their seminars: "I never use the GUI. I only use the command line."

-a