[llvm] [IA]: Construct (de)interleave4 out of (de)interleave2 (PR #89276)

[Paul Walker via llvm-commits]

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@@ -16441,17 +16441,56 @@ bool AArch64TargetLowering::lowerInterleavedStore(StoreInst *SI,
   return true;
 }
 
+bool GetDeinterleaveLeaves(Value *DI,
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paulwalker-arm wrote:

The coding standard requires functions to start with lowercase.

https://github.com/llvm/llvm-project/pull/89276