[llvm] [VPlan] Impl VPlan-based pattern match for ExtendedRed and MulAccRed (NFCI) (PR #113903)

[Florian Hahn via llvm-commits]

================
@@ -2653,6 +2657,260 @@ class VPReductionEVLRecipe : public VPReductionRecipe {
   }
 };
 
+/// A recipe to represent inloop extended reduction operations, performing a
+/// reduction on a vector operand into a scalar value, and adding the result to
+/// a chain. This recipe is high level abstract which will generate
+/// VPReductionRecipe and VPWidenCastRecipe before execution. The Operands are
+/// {ChainOp, VecOp, [Condition]}.
+class VPExtendedReductionRecipe : public VPSingleDefRecipe {
+  /// The recurrence decriptor for the reduction in question.
+  const RecurrenceDescriptor &RdxDesc;
+  bool IsOrdered;
+  /// Whether the reduction is conditional.
+  bool IsConditional = false;
+  /// Type after extend.
+  Type *ResultTy;
+  /// Opcode for the extend instruction.
+  Instruction::CastOps ExtOp;
+  CastInst *ExtInstr;
+  bool IsZExt;
+
+protected:
+  VPExtendedReductionRecipe(const unsigned char SC,
+                            const RecurrenceDescriptor &R, Instruction *RedI,
+                            Instruction::CastOps ExtOp, CastInst *ExtI,
+                            ArrayRef<VPValue *> Operands, VPValue *CondOp,
+                            bool IsOrdered, Type *ResultTy)
+      : VPSingleDefRecipe(SC, Operands, RedI), RdxDesc(R), IsOrdered(IsOrdered),
+        ResultTy(ResultTy), ExtOp(ExtOp), ExtInstr(ExtI) {
+    if (CondOp) {
+      IsConditional = true;
+      addOperand(CondOp);
+    }
+    IsZExt = ExtOp == Instruction::CastOps::ZExt;
+  }
+
+public:
+  VPExtendedReductionRecipe(const RecurrenceDescriptor &R, Instruction *RedI,
+                            VPValue *ChainOp, VPWidenCastRecipe *Ext,
+                            VPValue *CondOp, bool IsOrdered)
+      : VPExtendedReductionRecipe(
+            VPDef::VPExtendedReductionSC, R, RedI, Ext->getOpcode(),
+            cast<CastInst>(Ext->getUnderlyingInstr()),
+            ArrayRef<VPValue *>({ChainOp, Ext->getOperand(0)}), CondOp,
+            IsOrdered, Ext->getResultType()) {}
+
+  ~VPExtendedReductionRecipe() override = default;
+
+  VPExtendedReductionRecipe *clone() override {
+    llvm_unreachable("Not implement yet");
+  }
+
+  static inline bool classof(const VPRecipeBase *R) {
+    return R->getVPDefID() == VPDef::VPExtendedReductionSC;
+  }
+
+  static inline bool classof(const VPUser *U) {
+    auto *R = dyn_cast<VPRecipeBase>(U);
+    return R && classof(R);
+  }
+
+  void execute(VPTransformState &State) override {
+    llvm_unreachable("VPExtendedReductionRecipe should be transform to "
+                     "VPExtendedRecipe + VPReductionRecipe before execution.");
+  };
+
+  /// Return the cost of VPExtendedReductionRecipe.
+  InstructionCost computeCost(ElementCount VF,
+                              VPCostContext &Ctx) const override;
+
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
+  /// Print the recipe.
+  void print(raw_ostream &O, const Twine &Indent,
+             VPSlotTracker &SlotTracker) const override;
+#endif
+
+  /// Return the recurrence decriptor for the in-loop reduction.
+  const RecurrenceDescriptor &getRecurrenceDescriptor() const {
+    return RdxDesc;
+  }
+  /// Return true if the in-loop reduction is ordered.
+  bool isOrdered() const { return IsOrdered; };
+  /// Return true if the in-loop reduction is conditional.
+  bool isConditional() const { return IsConditional; };
+  /// The VPValue of the scalar Chain being accumulated.
+  VPValue *getChainOp() const { return getOperand(0); }
+  /// The VPValue of the vector value to be extended and reduced.
+  VPValue *getVecOp() const { return getOperand(1); }
+  /// The VPValue of the condition for the block.
+  VPValue *getCondOp() const {
+    return isConditional() ? getOperand(getNumOperands() - 1) : nullptr;
+  }
+  /// The Type after extended.
+  Type *getResultType() const { return ResultTy; };
+  /// The Opcode of extend instruction.
+  Instruction::CastOps getExtOpcode() const { return ExtOp; };
+  /// The CastInst of the extend instruction.
+  CastInst *getExtInstr() const { return ExtInstr; };
+};
+
+/// A recipe to represent inloop MulAccreduction operations, performing a
+/// reduction on a vector operand into a scalar value, and adding the result to
+/// a chain. This recipe is high level abstract which will generate
+/// VPReductionRecipe VPWidenRecipe(mul) and VPWidenCastRecipes before
+/// execution. The Operands are {ChainOp, VecOp1, VecOp2, [Condition]}.
+class VPMulAccRecipe : public VPSingleDefRecipe {
+  /// The recurrence decriptor for the reduction in question.
+  const RecurrenceDescriptor &RdxDesc;
+  bool IsOrdered;
+  /// Whether the reduction is conditional.
+  bool IsConditional = false;
+  /// Type after extend.
+  Type *ResultType;
+  // Note that all extend instruction must have the same opcode in MulAcc.
+  Instruction::CastOps ExtOp;
+
+  /// reduce.add(ext(mul(ext0(), ext1())))
+  Instruction *MulInstr;
----------------
fhahn wrote:

Not sure if this is still at the correct line, main point was to avoid duplicating things from the parent class. The general point about avoiding references to IR would still apply to the instruction references here and elsewhere

https://github.com/llvm/llvm-project/pull/113903