[clang] [llvm] Remove mmx 3dnow (PR #96246)

[Simon Pilgrim via llvm-commits]

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@@ -1825,32 +1818,32 @@ def : ProcModel<P, SapphireRapidsModel,
 
 def : Proc<"k6",   [FeatureX87, FeatureCX8, FeatureMMX],
                    [TuningSlowUAMem16, TuningInsertVZEROUPPER]>;
-def : Proc<"k6-2", [FeatureX87, FeatureCX8, Feature3DNow],
+def : Proc<"k6-2", [FeatureX87, FeatureCX8, FeatureMMX],
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RKSimon wrote:

I think the best we can do is add FeaturePRFCHW as well?

https://github.com/llvm/llvm-project/pull/96246