This is a research project from Georgia Tech. There's a homepage at [0] and a paper at [1]. It is specialized to run OpenCL, but with a bit of support for the graphics pipeline, mostly a texture fetch instruction. It appears to be fairly vanilla RISC-V overall, with a small number of additional instructions to support GPU. I'm very happy to see this kind of thing, as I think there's a lot of design space to explore, and it's great that some of that is happening in academic spaces.
Intel's Larabee/Xeon Phi shows that there's a ton of potential here.
Intel's big issue is that x86 is incredibly inefficient. Implementing the base instruction set is very difficult. Trying to speed it up at all starts drastically increasing core size. This means that the SIMD to overhead ratio is pretty high
RISC-V excels at tiny implementations and power efficiency. The ratio of SIMD to the rest of the core should be much higher resulting in overall better efficiency.
The final design (at a high level) seems somewhat similar to AMD's RDNA with a scalar ALU doing the flow control while a very wide SIMD does the bulk of the calculations.
[0]: https://vortex.cc.gatech.edu/
[1]: https://vortex.cc.gatech.edu/publications/vortex_micro21_fin...