[llvm] [AArch64] Support symmetric complex deinterleaving with higher factors (PR #151295)

[Igor Kirillov via llvm-commits]

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@@ -1890,22 +2016,53 @@ ComplexDeinterleavingGraph::identifyRoot(Instruction *RootI) {
 }
 
 ComplexDeinterleavingGraph::NodePtr
-ComplexDeinterleavingGraph::identifyDeinterleave(Instruction *Real,
-                                                 Instruction *Imag) {
-  Instruction *I = nullptr;
-  Value *FinalValue = nullptr;
-  if (match(Real, m_ExtractValue<0>(m_Instruction(I))) &&
-      match(Imag, m_ExtractValue<1>(m_Specific(I))) &&
-      match(I, m_Intrinsic<Intrinsic::vector_deinterleave2>(
-                   m_Value(FinalValue)))) {
+ComplexDeinterleavingGraph::identifyDeinterleave(ComplexValues &Vals) {
+  Instruction *II = nullptr;
+
+  // Must be at least one complex value.
+  for (unsigned Idx = 0; Idx < Vals.size(); Idx++) {
+    auto *EVI = dyn_cast<ExtractValueInst>(Vals[Idx].Real);
+    if (!EVI || EVI->getNumIndices() != 1 ||
+        EVI->getIndices()[0] != (Idx * 2) ||
+        (Idx != 0 && II != EVI->getAggregateOperand())) {
+      II = nullptr;
+      break;
+    }
+    if (Idx == 0) {
+      II = dyn_cast<Instruction>(EVI->getAggregateOperand());
+      if (!II)
+        break;
+    }
+    EVI = dyn_cast<ExtractValueInst>(Vals[Idx].Imag);
+    if (!EVI || EVI->getNumIndices() != 1 ||
+        EVI->getIndices()[0] != ((Idx * 2) + 1) ||
+        II != EVI->getAggregateOperand()) {
+      II = nullptr;
+      break;
+    }
+  }
+
+  if (II && isa<IntrinsicInst>(II)) {
+    if (cast<IntrinsicInst>(II)->getIntrinsicID() !=
----------------
igogo-x86 wrote:

We can cast and check for null simultaneously using:
```
if (auto *IntrinsicII = dyn_cast_or_null<IntrinsicInst>(II))
```

https://github.com/llvm/llvm-project/pull/151295