I am not sure yet of which version of the libraries you are using. I downloaded the Adafruit_St7735 library from Adafruit and it did not compile. So I hacked up a version of it, that does. Most of it was running real real slow, so I hacked in some of the speed up code for ILI9341 driver to it and it is working quite a bit better.
The code is not in great shape yet, probably won't compile except on Edison maybe Galileo, but I uploaded it to a new branch on my github projects
https://github.com/KurtE/Adafruit-ST7735-Library/tree/Intel-Edison
There are still more speed ups that are needed, including probably ones that you need for drawing images, but rectangles, fast lines... are much faster.
Warning not sure yet how much I will do on this library as for the most part I use other displays, but was curious. May try it out my Galileo V2 when it arrives.