[PATCH] D137695: [X86] Add missing Zen3 model subtypes

[Freddy, Ye via Phabricator via llvm-commits]

FreddyYe added inline comments.


================
Comment at: compiler-rt/lib/builtins/cpu_model.c:593
     }
+    if (Model >= 0x40 && Model <= 0x5f) {
+      *Subtype = AMDFAM19H_ZNVER3;
----------------
RKSimon wrote:
> FreddyYe wrote:
> > Where can we find the Model values? Meanwhile I cannot find the new condition in gcc's codes either.
> AMD are really slow at providing this kind of documentation and its a mess - there is a reference to Fam19h-51h at https://www.amd.com/en/support/tech-docs?keyword=19h but not the rest of the range.
> 
> As I said in the summary I took the CPUIDs that have been seen by InstLatx64 and mapped those to the linux kernel code for confirmation - the best you can then do is look at the git history of the file to see when those cases were added, at least some of those change came from the AMD kernel team.
> 
> gcc might not have bothered as zen3+ is really just changes to IGPU and cache, not the ISA feature/tuning set.
> 
> @lebedev.ri Might be able to give a little more insight - I based this change off his previous patch for additional zen3 models: D121708
Thanks for your detailed explaining!


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  https://reviews.llvm.org/D137695/new/

https://reviews.llvm.org/D137695