[llvm] [AArch64] Disconnect FeatureUseScalarIncVL from FeatureSVE2. (PR #114568)

[Sander de Smalen via llvm-commits]

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@@ -417,6 +417,8 @@ class AArch64Subtarget final : public AArch64GenSubtargetInfo {
     return DefaultSVETFOpts;
   }
 
+  bool useScalarIncVL() const;
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sdesmalen-arm wrote:

nit: maybe add a comment to explain what `useScalarIncVL` means?

https://github.com/llvm/llvm-project/pull/114568