R600g "Soft" FP64 Shows Signs Of Life, Enabling Older GPUs To Have OpenGL 4 In 2018

Most pre-GCN AMD graphics cards are still limited to OpenGL 3.3 support at this time due to not supporting FP64. Only the HD 5800/6900 series on R600g currently have real double-precision floating-point support working right now so at present they are on OpenGL 4.3 rather than 3.3, but those other generations may be catching up soon thanks to the "soft" FP64 code...