[llvm] [SLP] Make getSameOpcode support different instructions if they have same semantics. (PR #112181)

[Alexey Bataev via llvm-commits]

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@@ -3252,15 +3413,25 @@ class BoUpSLP {
       auto *I0 = cast<Instruction>(Scalars[0]);
       Operands.resize(I0->getNumOperands());
       unsigned NumLanes = Scalars.size();
-      for (unsigned OpIdx = 0, NumOperands = I0->getNumOperands();
-           OpIdx != NumOperands; ++OpIdx) {
+      unsigned NumOperands = I0->getNumOperands();
+      for (unsigned OpIdx : seq<unsigned>(NumOperands))
         Operands[OpIdx].resize(NumLanes);
-        for (unsigned Lane = 0; Lane != NumLanes; ++Lane) {
-          auto *I = cast<Instruction>(Scalars[Lane]);
-          assert(I->getNumOperands() == NumOperands &&
-                 "Expected same number of operands");
-          Operands[OpIdx][Lane] = I->getOperand(OpIdx);
-        }
+      for (auto [I, V] : enumerate(Scalars)) {
+        SmallVector<InterchangeableInstruction> IIList =
+            getInterchangeableInstruction(cast<Instruction>(V));
+        auto Iter = find_if(IIList, [&](const InterchangeableInstruction &II) {
+          return II.Opcode == MainOp->getOpcode();
+        });
+        if (Iter == IIList.end())
+          Iter = find_if(IIList, [&](const InterchangeableInstruction &II) {
+            return II.Opcode == AltOp->getOpcode();
+          });
+        assert(Iter != IIList.end() &&
+               "Cannot find an interchangeable instruction.");
+        assert(Iter->Ops.size() == NumOperands &&
+               "Expected same number of operands");
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alexey-bataev wrote:

Same, try to add extra operand to getInterchangeableInstruction to allow filtering inside

https://github.com/llvm/llvm-project/pull/112181