もう実装されてる

AMD FSR has now been ported to the Slang format as a pixel/vertex shader!
https://twitter.com/libretro/status/1433511745641922572
https://www.libretro.com/index.php/category/amd-fsr/

https://www.libretro.com/wp-content/uploads/2021/09/Ys_Seven_undub-fsr.png
https://www.libretro.com/wp-content/uploads/2021/09/Gradius_V_Japan-210902-125220.png
https://www.libretro.com/wp-content/uploads/2021/09/Untitled-1.png
https://twitter.com/5chan_nel (5ch newer account)