It's worth noting that upstream gdb (and clang) are somewhat limited in GPU debugging support because they only use (and emit) standardized DWARF debug information. The DWARF standard will need updates before gdb and clang can reach parity with the AMD forks, rocgdb and amdclang, in terms of debugging support. It's nothing fundamental, but the AMD forks use experimental DWARF features and the upstream projects do not.

It's a little out of date now, but Lance Six had a presentation about the state of AMD GPU debugging in upstream gdb at FOSDEM 2024. https://archive.fosdem.org/2024/events/attachments/fosdem-20...

amd gdb is an actual debugger but it only works with applications that emit dwarf and use the amdkfd KMD aka it doesn't work with graphics .. all of the rest are not a actual debuggers .. UMR does support wave stepping but it doesn't try to be a shader debugger rather a tool for drivers developers and the AMD tools doesn't have any debugging capabilities.

to be fair it wasn't clear that was an official AMD debugger and besides that's only for debugging ROCm applications.