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

[Paul Walker via llvm-commits]

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@@ -510,12 +511,57 @@ bool InterleavedAccessImpl::lowerDeinterleaveIntrinsic(
 
   LLVM_DEBUG(dbgs() << "IA: Found a deinterleave intrinsic: " << *DI << "\n");
 
+  std::stack<IntrinsicInst *> DeinterleaveTreeQueue;
+  SmallVector<Value *> TempLeafNodes, LeafNodes;
+  std::map<IntrinsicInst *, bool> mp;
+  SmallVector<Instruction *> TempDeadInsts;
+
+  DeinterleaveTreeQueue.push(DI);
+  while (!DeinterleaveTreeQueue.empty()) {
+    auto CurrentDI = DeinterleaveTreeQueue.top();
+    DeinterleaveTreeQueue.pop();
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paulwalker-arm wrote:

My comment about the interleave parsing also applies here in that I was anticipating a simple pattern match.

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