New Information on AMD RDNA Architecture

Recent updates to the AMDGPU LLVM back-end have revealed further details about the architecture of the AMD GFX1170 GPU, codenamed "RDNA 4m". This GPU, previously identified as part of an APU/SoC, is of interest due to its membership in the GFX11 series while presenting characteristics more akin to the RDNA4 architecture.

The ISA changes recently implemented in the AMDGPU LLVM back-end highlight a convergence towards the instructions typical of RDNA4. The GFX11 series is primarily associated with RDNA3, with the GFX115x variants representing RDNA 3.5. The RDNA4 architecture is instead identified by the GFX12 series.

These developments suggest that AMD may be exploring hybrid configurations or specialized variants of the RDNA architecture, potentially optimized for specific use cases or market segments. Further analysis will be needed to fully understand the implications of these changes and their impact on the performance and capabilities of the GFX1170 GPU.