[llvm] [LV][AArch64]: Utilise SVE ld4/st4 instructions via auto-vectorisation (PR #89018)

[Mel Chen via llvm-commits]

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@@ -2572,23 +2586,40 @@ void InnerLoopVectorizer::vectorizeInterleaveGroup(
     }
 
     if (VecTy->isScalableTy()) {
-      assert(InterleaveFactor == 2 &&
-             "Unsupported deinterleave factor for scalable vectors");
-
+      assert(isPowerOf2_32(InterleaveFactor)  &&
+            "Unsupported deinterleave factor for scalable vectors");
       for (unsigned Part = 0; Part < UF; ++Part) {
         // Scalable vectors cannot use arbitrary shufflevectors (only splats),
         // so must use intrinsics to deinterleave.
-        Value *DI = Builder.CreateIntrinsic(
-            Intrinsic::experimental_vector_deinterleave2, VecTy, NewLoads[Part],
-            /*FMFSource=*/nullptr, "strided.vec");
+        
+        std::queue<Value *>Queue;
+        Queue.push(NewLoads[Part]);
+        // NonLeaf represents how many times we will do deinterleaving,
+        // think of it as a tree, each node will be deinterleaved, untill we reach to
+        // the leaf nodes which will be the final results of deinterleaving.
+        unsigned NonLeaf = InterleaveFactor - 1;
+        for (unsigned i = 0; i < NonLeaf; i ++) {
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Mel-Chen wrote:

`i` --> `I`
`i ++` --> `I++`

https://github.com/llvm/llvm-project/pull/89018