AMD Zen 4 "znver4" Support Lands In GNU Binutils

For going along with the recently merged initial AMD Zen 4 "znver4" support in GCC 13 (in case you missed it, there is further tuning work still ongoing), the Zen 4 support has now been merged to GNU Binutils.

AMD last month sent out their Znver4 patch to GNU Binutils for adding the Znver4 target to the GNU Assembler "Gas" with the new instruction additions. As of yesterday, that Binutils patch has now been merged to mainline.

The Znver4 patch also adds in the RMPQUERY instruction. RMPQUERY hasn't been talked about too much with Zen 4 but is a new instruction for reading the Reverse Map Table (RMP) permission mask for an SEV-SNP guest page. AMD's Reverse Map Table added with Secure Encrypted Virtualization SNP is used for managing the one-to-one mapping between system physical addresses and guest physical addresses. Meanwhile the other new instructions with Zen 4 are already supported with Binutils thanks to the years of AVX-512 work by Intel, etc.

In case you missed it, see yesterday's AMD EPYC 9374F review as an exciting Zen 4 32-core server chip.

This AMD Zen 4 support in GNU Binutils will be part of the Binutils 2.40 release that like usual should see its release in February. Binutils 2.40 is also the release where on the Intel side support is added for RAO-INT, AVX-NE-CONVERT, MSRLIST, WRMSRNS, AVX-VNNI-INT8, AVX-IFMA, PREFETCHI, AMX-FP16, and other instructions coming with Intel's 2023~2024 processors. As I've said repeatedly, Intel's Linux engineers continue to be much more punctual in their open-source compiler toolchain enablement work than AMD but hopefully that will eventually improve for future Zen generations as AMD continues ramping up its engineering staff and seeing the importance of quality Linux support in time for launch.