[timhigins]

Exactly and see also ROCM/HIP which is AMD’s reimplementation of CUDA for their gpus.

[pjmlp]

Reimplementation of CUDA C++, not CUDA.

CUDA is a set of four compilers, namely C, C++, Fortran and Python JIT DSLs, a bytecode and two compiler backend libraries, a set of compute libraries collection for the languages listed above, plugins for Eclipse and Visual Studio, a GPU graphical debugger and profiler.

[qalmakka]

There's ZLUDA for AMD that actually implements CUDA, but it's still quite immature yet