AMD GFX1170 “RDNA 4m” target gains more RDNA 4 style ISA changes in LLVM
Linux compiler work for AMD’s Radeon stack is revealing more about a new “ GFX1170 ” GPU target that is tagged as an APU or SoC part and labeled “ RDNA 4m “, despite sitting in the GFX11 family associated with RDNA 3. Phoronix reports that recent changes in the AMDGPU backend for LLVM continue to push GFX1170’s instruction set closer to RDNA 4 behavior in a few specific areas.
GFX1170 first appeared earlier this month as a new LLVM target with a small set of feature differences versus existing GFX11 targets, and follow-up work added FP8 and BF8 conversion support. That combination is part of why the “RDNA 4m” label drew attention, since RDNA 4 is typically associated with GFX12, not GFX11.
Source: Github/Phoronix
One of the latest merged changes adds WMMA and SWMMAC instruction support for GFX1170. The commit introduces new subtarget features to separate GFX11 WMMA instruction handling from GFX1170 and GFX12 behavior, including adding WMMA128b variants and using a suffix scheme for GFX11.7 instructions to avoid decode conflicts. These are matrix-oriented instructions that are commonly discussed in the context of AI and other compute workloads.
Source: Github/Phoronix
AMD Ryzen 500 series with FSR 4 support
As reported earlier, AMD’s Ryzen 500 series, known as “Medusa Point” and “Medusa Halo”, is expected to use Zen 6 CPU cores. Integrated graphics looks split, with the Halo parts reportedly set to use RDNA 5, while mainstream APUs are expected to remain on RDNA 3.5+.
FP8 Support
- ❌AMD Strix Point ➡️RDNA3.5
- ❌AMD Strix Halo➡️RDNA3.5
- ✅AMD Medusa Point ➡️ RDNA3.5+/ RDNA4m
- ✅AMD Medusa Halo ➡️ RDNA5
That “plus” now appears to be shifting toward “RDNA 4m”. In theory, that would mean AMD could enable FSR 4 support on its next-generation APU line even if the baseline graphics core remains closer to the current generation. Future AMD APUs should theoretically be able to meet the feature requirements for FSR 4 support if they incorporate RDNA 4-style FP8 instructions.
Source: Phoronix
