[llvm] [Intrinsics][AArch64] Add intrinsic to mask off aliasing vector lanes (PR #117007)

[Sander de Smalen via llvm-commits]

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@@ -839,6 +839,10 @@ void TargetLoweringBase::initActions() {
     // Masked vector extracts default to expand.
     setOperationAction(ISD::VECTOR_FIND_LAST_ACTIVE, VT, Expand);
 
+    // Lane mask with non-aliasing lanes enabled default to expand
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sdesmalen-arm wrote:

nit: this sentence is a bit confusing, maybe just remove the comment? (it's clear from the code what this is doing)

https://github.com/llvm/llvm-project/pull/117007