[SLPVectorizer] Begin abstracting InstructionsState alternate matching away from opcodes. NFCI.

[RKSimon]

Summary

This is an early step towards matching Instructions by attributes other than the opcode. This will be necessary for cast/call alternates which share the same opcode but have different types/intrinsicIDs etc. - which we could vectorize as long as we split them using the alternate mechanism.

[dtemirbulatov]

Looks good for me.

lib/Transforms/Vectorize/SLPVectorizer.cpp

 
 namespace {
 
 /// Main data required for vectorization of instructions.
 struct InstructionsState {
   /// The very first instruction in the list with the main opcode.
   Value *OpValue = nullptr;
 
+  /// The main/alternate instruction.
+  Instruction *MainOp = nullptr;
+  Instruction *AltOp = nullptr;
+
   /// The main/alternate opcodes for the list of instructions.
-  unsigned Opcode = 0;
-  unsigned AltOpcode = 0;
+  unsigned getOpcode() const {
+    return MainOp ? MainOp->getOpcode() : 0;
+  }
+
+  unsigned getAltOpcode() const {
+    return AltOp ? AltOp->getOpcode() : 0;
+  }
 
   /// Some of the instructions in the list have alternate opcodes.
-  bool isAltShuffle() const { return Opcode != AltOpcode; }
+  bool isAltShuffle() const { return getOpcode() != getAltOpcode(); }
 
   bool isOpcodeOrAlt(Instruction *I) const {
     unsigned CheckedOpcode = I->getOpcode();
-    return Opcode == CheckedOpcode || AltOpcode == CheckedOpcode;
+    return getOpcode() == CheckedOpcode || getAltOpcode() == CheckedOpcode;
   }
 
-  InstructionsState() = default;
-  InstructionsState(Value *OpValue, unsigned Opcode, unsigned AltOpcode)
-      : OpValue(OpValue), Opcode(Opcode), AltOpcode(AltOpcode) {}
+  InstructionsState() = delete;
+  InstructionsState(Value *OpValue, Instruction *MainOp, Instruction *AltOp)
+      : OpValue(OpValue), MainOp(MainOp), AltOp(AltOp) {}
 };
 
 } // end anonymous namespace
 
 /// Chooses the correct key for scheduling data. If \p Op has the same (or
 /// alternate) opcode as \p OpValue, the key is \p Op. Otherwise the key is \p
 /// OpValue.
 static Value *isOneOf(const InstructionsState &S, Value *Op) {
   auto *I = dyn_cast<Instruction>(Op);
   if (I && S.isOpcodeOrAlt(I))
     return Op;
   return S.OpValue;
 }
 
 /// \returns analysis of the Instructions in \p VL described in
 /// InstructionsState, the Opcode that we suppose the whole list 
 /// could be vectorized even if its structure is diverse.
 static InstructionsState getSameOpcode(ArrayRef<Value *> VL,
                                        unsigned BaseIndex = 0) {
   // Make sure these are all Instructions.
   if (llvm::any_of(VL, [](Value *V) { return !isa<Instruction>(V); }))
-    return InstructionsState(VL[BaseIndex], 0, 0);
+    return InstructionsState(VL[BaseIndex], nullptr, nullptr);
 
   bool IsBinOp = isa<BinaryOperator>(VL[BaseIndex]);
   unsigned Opcode = cast<Instruction>(VL[BaseIndex])->getOpcode();
   unsigned AltOpcode = Opcode;
+  unsigned AltIndex = BaseIndex;
 
   // Check for one alternate opcode from another BinaryOperator.
   // TODO - can we support other operators (casts etc.)?
   for (int Cnt = 0, E = VL.size(); Cnt < E; Cnt++) {
     unsigned InstOpcode = cast<Instruction>(VL[Cnt])->getOpcode();
     if (InstOpcode != Opcode && InstOpcode != AltOpcode) {
       if (Opcode == AltOpcode && IsBinOp && isa<BinaryOperator>(VL[Cnt])) {
         AltOpcode = InstOpcode;
+        AltIndex = Cnt;
         continue;
       }
-      return InstructionsState(VL[BaseIndex], 0, 0);
+      return InstructionsState(VL[BaseIndex], nullptr, nullptr);
     }
   }
 
-  return InstructionsState(VL[BaseIndex], Opcode, AltOpcode);
+  return InstructionsState(VL[BaseIndex], cast<Instruction>(VL[BaseIndex]),
+                           cast<Instruction>(VL[AltIndex]));
 }
 
 /// \returns true if all of the values in \p VL have the same type or false
 /// otherwise.
 static bool allSameType(ArrayRef<Value *> VL) {
   Type *Ty = VL[0]->getType();
   for (int i = 1, e = VL.size(); i < e; i++)
     if (VL[i]->getType() != Ty)
void BoUpSLP::buildTree_rec(ArrayRef<Value *> VL, unsigned Depth,
   if (StoreInst *SI = dyn_cast<StoreInst>(S.OpValue))
     if (SI->getValueOperand()->getType()->isVectorTy()) {
       LLVM_DEBUG(dbgs() << "SLP: Gathering due to store vector type.\n");
       newTreeEntry(VL, false, UserTreeIdx);
       return;
     }
 
   // If all of the operands are identical or constant we have a simple solution.
-  if (allConstant(VL) || isSplat(VL) || !allSameBlock(VL) || !S.Opcode) {
+  if (allConstant(VL) || isSplat(VL) || !allSameBlock(VL) || !S.getOpcode()) {
     LLVM_DEBUG(dbgs() << "SLP: Gathering due to C,S,B,O. \n");
     newTreeEntry(VL, false, UserTreeIdx);
     return;
   }
 
   // We now know that this is a vector of instructions of the same type from
   // the same block.
 
assert((!BS.getScheduleData(VL0) ||
             !BS.getScheduleData(VL0)->isPartOfBundle()) &&
            "tryScheduleBundle should cancelScheduling on failure");
     newTreeEntry(VL, false, UserTreeIdx, ReuseShuffleIndicies);
     return;
   }
   LLVM_DEBUG(dbgs() << "SLP: We are able to schedule this bundle.\n");
 
   unsigned ShuffleOrOp = S.isAltShuffle() ?
-                (unsigned) Instruction::ShuffleVector : S.Opcode;
+                (unsigned) Instruction::ShuffleVector : S.getOpcode();
   switch (ShuffleOrOp) {
     case Instruction::PHI: {
       PHINode *PH = dyn_cast<PHINode>(VL0);
 
       // Check for terminator values (e.g. invoke).
       for (unsigned j = 0; j < VL.size(); ++j)
         for (unsigned i = 0, e = PH->getNumIncomingValues(); i < e; ++i) {
           TerminatorInst *Term = dyn_cast<TerminatorInst>(
switch (ShuffleOrOp) {
     case Instruction::Xor:
       newTreeEntry(VL, true, UserTreeIdx, ReuseShuffleIndicies);
       LLVM_DEBUG(dbgs() << "SLP: added a vector of bin op.\n");
 
       // Sort operands of the instructions so that each side is more likely to
       // have the same opcode.
       if (isa<BinaryOperator>(VL0) && VL0->isCommutative()) {
         ValueList Left, Right;
-        reorderInputsAccordingToOpcode(S.Opcode, VL, Left, Right);
+        reorderInputsAccordingToOpcode(S.getOpcode(), VL, Left, Right);
         buildTree_rec(Left, Depth + 1, UserTreeIdx);
         buildTree_rec(Right, Depth + 1, UserTreeIdx);
         return;
       }
 
       for (unsigned i = 0, e = VL0->getNumOperands(); i < e; ++i) {
         ValueList Operands;
         // Prepare the operand vector.
unsigned BoUpSLP::canMapToVector(Type *T, const DataLayout &DL) const {
   return N;
 }
 
 bool BoUpSLP::canReuseExtract(ArrayRef<Value *> VL, Value *OpValue,
                               SmallVectorImpl<unsigned> &CurrentOrder) const {
   Instruction *E0 = cast<Instruction>(OpValue);
   assert(E0->getOpcode() == Instruction::ExtractElement ||
          E0->getOpcode() == Instruction::ExtractValue);
-  assert(E0->getOpcode() == getSameOpcode(VL).Opcode && "Invalid opcode");
+  assert(E0->getOpcode() == getSameOpcode(VL).getOpcode() && "Invalid opcode");
   // Check if all of the extracts come from the same vector and from the
   // correct offset.
   Value *Vec = E0->getOperand(0);
 
   CurrentOrder.clear();
 
   // We have to extract from a vector/aggregate with the same number of elements.
   unsigned NElts;
int BoUpSLP::getEntryCost(TreeEntry *E) {
   }
   if (E->NeedToGather) {
     if (allConstant(VL))
       return 0;
     if (isSplat(VL)) {
       return ReuseShuffleCost +
              TTI->getShuffleCost(TargetTransformInfo::SK_Broadcast, VecTy, 0);
     }
-    if (getSameOpcode(VL).Opcode == Instruction::ExtractElement &&
+    if (getSameOpcode(VL).getOpcode() == Instruction::ExtractElement &&
         allSameType(VL) && allSameBlock(VL)) {
       Optional<TargetTransformInfo::ShuffleKind> ShuffleKind = isShuffle(VL);
       if (ShuffleKind.hasValue()) {
         int Cost = TTI->getShuffleCost(ShuffleKind.getValue(), VecTy);
         for (auto *V : VL) {
           // If all users of instruction are going to be vectorized and this
           // instruction itself is not going to be vectorized, consider this
           // instruction as dead and remove its cost from the final cost of the
           // vectorized tree.
           if (areAllUsersVectorized(cast<Instruction>(V)) &&
               !ScalarToTreeEntry.count(V)) {
             auto *IO = cast<ConstantInt>(
                 cast<ExtractElementInst>(V)->getIndexOperand());
             Cost -= TTI->getVectorInstrCost(Instruction::ExtractElement, VecTy,
                                             IO->getZExtValue());
           }
         }
         return ReuseShuffleCost + Cost;
       }
     }
     return ReuseShuffleCost + getGatherCost(VL);
   }
   InstructionsState S = getSameOpcode(VL);
-  assert(S.Opcode && allSameType(VL) && allSameBlock(VL) && "Invalid VL");
+  assert(S.getOpcode() && allSameType(VL) && allSameBlock(VL) && "Invalid VL");
   Instruction *VL0 = cast<Instruction>(S.OpValue);
   unsigned ShuffleOrOp = S.isAltShuffle() ?
-               (unsigned) Instruction::ShuffleVector : S.Opcode;
+               (unsigned) Instruction::ShuffleVector : S.getOpcode();
   switch (ShuffleOrOp) {
     case Instruction::PHI:
       return 0;
 
     case Instruction::ExtractValue:
     case Instruction::ExtractElement:
       if (NeedToShuffleReuses) {
         unsigned Idx = 0;
switch (ShuffleOrOp) {
     case Instruction::UIToFP:
     case Instruction::Trunc:
     case Instruction::FPTrunc:
     case Instruction::BitCast: {
       Type *SrcTy = VL0->getOperand(0)->getType();
       if (NeedToShuffleReuses) {
         ReuseShuffleCost -=
             (ReuseShuffleNumbers - VL.size()) *
-            TTI->getCastInstrCost(S.Opcode, ScalarTy, SrcTy, VL0);
+            TTI->getCastInstrCost(S.getOpcode(), ScalarTy, SrcTy, VL0);
       }
 
       // Calculate the cost of this instruction.
       int ScalarCost = VL.size() * TTI->getCastInstrCost(VL0->getOpcode(),
                                                          VL0->getType(), SrcTy, VL0);
 
       VectorType *SrcVecTy = VectorType::get(SrcTy, VL.size());
       int VecCost = 0;
       // Check if the values are candidates to demote.
       if (!MinBWs.count(VL0) || VecTy != SrcVecTy) {
         VecCost = ReuseShuffleCost +
                   TTI->getCastInstrCost(VL0->getOpcode(), VecTy, SrcVecTy, VL0);
       }
       return VecCost - ScalarCost;
     }
     case Instruction::FCmp:
     case Instruction::ICmp:
     case Instruction::Select: {
       // Calculate the cost of this instruction.
       if (NeedToShuffleReuses) {
         ReuseShuffleCost -= (ReuseShuffleNumbers - VL.size()) *
-                            TTI->getCmpSelInstrCost(S.Opcode, ScalarTy,
+                            TTI->getCmpSelInstrCost(S.getOpcode(), ScalarTy,
                                                     Builder.getInt1Ty(), VL0);
       }
       VectorType *MaskTy = VectorType::get(Builder.getInt1Ty(), VL.size());
       int ScalarCost = VecTy->getNumElements() *
-          TTI->getCmpSelInstrCost(S.Opcode, ScalarTy, Builder.getInt1Ty(), VL0);
-      int VecCost = TTI->getCmpSelInstrCost(S.Opcode, VecTy, MaskTy, VL0);
+                       TTI->getCmpSelInstrCost(S.getOpcode(), ScalarTy,
+                                               Builder.getInt1Ty(), VL0);
+      int VecCost = TTI->getCmpSelInstrCost(S.getOpcode(), VecTy, MaskTy, VL0);
       return ReuseShuffleCost + VecCost - ScalarCost;
     }
     case Instruction::Add:
     case Instruction::FAdd:
     case Instruction::Sub:
     case Instruction::FSub:
     case Instruction::Mul:
     case Instruction::FMul:
case Instruction::Xor: {
         if (CInt0 != CInt)
           Op2VK = TargetTransformInfo::OK_NonUniformConstantValue;
       }
 
       SmallVector<const Value *, 4> Operands(VL0->operand_values());
       if (NeedToShuffleReuses) {
         ReuseShuffleCost -=
             (ReuseShuffleNumbers - VL.size()) *
-            TTI->getArithmeticInstrCost(S.Opcode, ScalarTy, Op1VK, Op2VK, Op1VP,
-                                        Op2VP, Operands);
+            TTI->getArithmeticInstrCost(S.getOpcode(), ScalarTy, Op1VK, Op2VK,
+                                        Op1VP, Op2VP, Operands);
       }
       int ScalarCost =
           VecTy->getNumElements() *
-          TTI->getArithmeticInstrCost(S.Opcode, ScalarTy, Op1VK, Op2VK, Op1VP,
-                                      Op2VP, Operands);
-      int VecCost = TTI->getArithmeticInstrCost(S.Opcode, VecTy, Op1VK, Op2VK,
-                                                Op1VP, Op2VP, Operands);
+          TTI->getArithmeticInstrCost(S.getOpcode(), ScalarTy, Op1VK, Op2VK,
+      int VecCost = TTI->getArithmeticInstrCost(S.getOpcode(), VecTy, Op1VK,
+                                                Op2VK, Op1VP, Op2VP, Operands);
       return ReuseShuffleCost + VecCost - ScalarCost;
     }
     case Instruction::GetElementPtr: {
       TargetTransformInfo::OperandValueKind Op1VK =
           TargetTransformInfo::OK_AnyValue;
       TargetTransformInfo::OperandValueKind Op2VK =
           TargetTransformInfo::OK_UniformConstantValue;
 
case Instruction::Call: {
 
       LLVM_DEBUG(dbgs() << "SLP: Call cost " << VecCallCost - ScalarCallCost
                         << " (" << VecCallCost << "-" << ScalarCallCost << ")"
                         << " for " << *CI << "\n");
 
       return ReuseShuffleCost + VecCallCost - ScalarCallCost;
     }
     case Instruction::ShuffleVector: {
-      assert(S.isAltShuffle() && Instruction::isBinaryOp(S.Opcode) &&
-             Instruction::isBinaryOp(S.AltOpcode) &&
+      assert(S.isAltShuffle() && Instruction::isBinaryOp(S.getOpcode()) &&
+             Instruction::isBinaryOp(S.getAltOpcode()) &&
              "Invalid Shuffle Vector Operand");
       int ScalarCost = 0;
       if (NeedToShuffleReuses) {
         for (unsigned Idx : E->ReuseShuffleIndices) {
           Instruction *I = cast<Instruction>(VL[Idx]);
           ReuseShuffleCost -=
               TTI->getArithmeticInstrCost(I->getOpcode(), ScalarTy);
         }
         for (Value *V : VL) {
           Instruction *I = cast<Instruction>(V);
           ReuseShuffleCost +=
               TTI->getArithmeticInstrCost(I->getOpcode(), ScalarTy);
         }
       }
       int VecCost = 0;
       for (Value *i : VL) {
         Instruction *I = cast<Instruction>(i);
         assert(S.isOpcodeOrAlt(I) && "Unexpected main/alternate opcode");
         ScalarCost += TTI->getArithmeticInstrCost(I->getOpcode(), ScalarTy);
       }
       // VecCost is equal to sum of the cost of creating 2 vectors
       // and the cost of creating shuffle.
-      VecCost = TTI->getArithmeticInstrCost(S.Opcode, VecTy);
-      VecCost += TTI->getArithmeticInstrCost(S.AltOpcode, VecTy);
+      VecCost = TTI->getArithmeticInstrCost(S.getOpcode(), VecTy);
+      VecCost += TTI->getArithmeticInstrCost(S.getAltOpcode(), VecTy);
       VecCost += TTI->getShuffleCost(TargetTransformInfo::SK_Select, VecTy, 0);
       return ReuseShuffleCost + VecCost - ScalarCost;
     }
     default:
       llvm_unreachable("Unknown instruction");
   }
 }
 
for (unsigned i = 0; i < Ty->getNumElements(); ++i) {
     }
   }
 
   return Vec;
 }
 
 Value *BoUpSLP::vectorizeTree(ArrayRef<Value *> VL) {
   InstructionsState S = getSameOpcode(VL);
-  if (S.Opcode) {
+  if (S.getOpcode()) {
     if (TreeEntry *E = getTreeEntry(S.OpValue)) {
       if (E->isSame(VL)) {
         Value *V = vectorizeTree(E);
         if (VL.size() == E->Scalars.size() && !E->ReuseShuffleIndices.empty()) {
           // We need to get the vectorized value but without shuffle.
           if (auto *SV = dyn_cast<ShuffleVectorInst>(V)) {
             V = SV->getOperand(0);
           } else {
if (NeedToShuffleReuses) {
         CSEBlocks.insert(I->getParent());
       }
     }
     E->VectorizedValue = V;
     return V;
   }
 
   unsigned ShuffleOrOp = S.isAltShuffle() ?
-           (unsigned) Instruction::ShuffleVector : S.Opcode;
+           (unsigned) Instruction::ShuffleVector : S.getOpcode();
   switch (ShuffleOrOp) {
     case Instruction::PHI: {
       PHINode *PH = dyn_cast<PHINode>(VL0);
       Builder.SetInsertPoint(PH->getParent()->getFirstNonPHI());
       Builder.SetCurrentDebugLocation(PH->getDebugLoc());
       PHINode *NewPhi = Builder.CreatePHI(VecTy, PH->getNumIncomingValues());
       Value *V = NewPhi;
       if (NeedToShuffleReuses) {
case Instruction::ICmp: {
 
       if (E->VectorizedValue) {
         LLVM_DEBUG(dbgs() << "SLP: Diamond merged for " << *VL0 << ".\n");
         return E->VectorizedValue;
       }
 
       CmpInst::Predicate P0 = cast<CmpInst>(VL0)->getPredicate();
       Value *V;
-      if (S.Opcode == Instruction::FCmp)
+      if (S.getOpcode() == Instruction::FCmp)
         V = Builder.CreateFCmp(P0, L, R);
       else
         V = Builder.CreateICmp(P0, L, R);
 
       propagateIRFlags(V, E->Scalars, VL0);
       if (NeedToShuffleReuses) {
         V = Builder.CreateShuffleVector(V, UndefValue::get(VecTy),
                                         E->ReuseShuffleIndices, "shuffle");
switch (ShuffleOrOp) {
     case Instruction::Shl:
     case Instruction::LShr:
     case Instruction::AShr:
     case Instruction::And:
     case Instruction::Or:
     case Instruction::Xor: {
       ValueList LHSVL, RHSVL;
       if (isa<BinaryOperator>(VL0) && VL0->isCommutative())
-        reorderInputsAccordingToOpcode(S.Opcode, E->Scalars, LHSVL,
+        reorderInputsAccordingToOpcode(S.getOpcode(), E->Scalars, LHSVL,
                                        RHSVL);
       else
         for (Value *V : E->Scalars) {
           auto *I = cast<Instruction>(V);
           LHSVL.push_back(I->getOperand(0));
           RHSVL.push_back(I->getOperand(1));
         }
 
       setInsertPointAfterBundle(E->Scalars, S);
 
       Value *LHS = vectorizeTree(LHSVL);
       Value *RHS = vectorizeTree(RHSVL);
 
       if (E->VectorizedValue) {
         LLVM_DEBUG(dbgs() << "SLP: Diamond merged for " << *VL0 << ".\n");
         return E->VectorizedValue;
       }
 
       Value *V = Builder.CreateBinOp(
-          static_cast<Instruction::BinaryOps>(S.Opcode), LHS, RHS);
+          static_cast<Instruction::BinaryOps>(S.getOpcode()), LHS, RHS);
       propagateIRFlags(V, E->Scalars, VL0);
       if (auto *I = dyn_cast<Instruction>(V))
         V = propagateMetadata(I, E->Scalars);
 
       if (NeedToShuffleReuses) {
         V = Builder.CreateShuffleVector(V, UndefValue::get(VecTy),
                                         E->ReuseShuffleIndices, "shuffle");
       }
case Instruction::Call: {
                                         E->ReuseShuffleIndices, "shuffle");
       }
       E->VectorizedValue = V;
       ++NumVectorInstructions;
       return V;
     }
     case Instruction::ShuffleVector: {
       ValueList LHSVL, RHSVL;
-      assert(S.isAltShuffle() && Instruction::isBinaryOp(S.Opcode) &&
-             Instruction::isBinaryOp(S.AltOpcode) &&
+      assert(S.isAltShuffle() && Instruction::isBinaryOp(S.getOpcode()) &&
+             Instruction::isBinaryOp(S.getAltOpcode()) &&
              "Invalid Shuffle Vector Operand");
       reorderAltShuffleOperands(S, E->Scalars, LHSVL, RHSVL);
       setInsertPointAfterBundle(E->Scalars, S);
 
       Value *LHS = vectorizeTree(LHSVL);
       Value *RHS = vectorizeTree(RHSVL);
 
       if (E->VectorizedValue) {
         LLVM_DEBUG(dbgs() << "SLP: Diamond merged for " << *VL0 << ".\n");
         return E->VectorizedValue;
       }
 
       // Create a vector of LHS op1 RHS
       Value *V0 = Builder.CreateBinOp(
-          static_cast<Instruction::BinaryOps>(S.Opcode), LHS, RHS);
+          static_cast<Instruction::BinaryOps>(S.getOpcode()), LHS, RHS);
 
       // Create a vector of LHS op2 RHS
       Value *V1 = Builder.CreateBinOp(
-          static_cast<Instruction::BinaryOps>(S.AltOpcode), LHS, RHS);
+          static_cast<Instruction::BinaryOps>(S.getAltOpcode()), LHS, RHS);
 
       // Create shuffle to take alternate operations from the vector.
       // Also, gather up odd and even scalar ops to propagate IR flags to
       // each vector operation.
       ValueList OpScalars, AltScalars;
       unsigned e = E->Scalars.size();
       SmallVector<Constant *, 8> Mask(e);
       for (unsigned i = 0; i < e; ++i) {
         auto *OpInst = cast<Instruction>(E->Scalars[i]);
         assert(S.isOpcodeOrAlt(OpInst) && "Unexpected main/alternate opcode");
-        if (OpInst->getOpcode() == S.AltOpcode) {
+        if (OpInst->getOpcode() == S.getAltOpcode()) {
           Mask[i] = Builder.getInt32(e + i);
           AltScalars.push_back(E->Scalars[i]);
         } else {
           Mask[i] = Builder.getInt32(i);
           OpScalars.push_back(E->Scalars[i]);
         }
       }
 
if (VL.size() < 2)
     return false;
 
   LLVM_DEBUG(dbgs() << "SLP: Trying to vectorize a list of length = "
                     << VL.size() << ".\n");
 
   // Check that all of the parts are scalar instructions of the same type,
   // we permit an alternate opcode via InstructionsState.
   InstructionsState S = getSameOpcode(VL);
-  if (!S.Opcode)
+  if (!S.getOpcode())
     return false;
 
   Instruction *I0 = cast<Instruction>(S.OpValue);
   unsigned Sz = R.getVectorElementSize(I0);
   unsigned MinVF = std::max(2U, R.getMinVecRegSize() / Sz);
   unsigned MaxVF = std::max<unsigned>(PowerOf2Floor(VL.size()), MinVF);
   if (MaxVF < 2) {
      R.getORE()->emit([&]() {