[NFC][CostModel]Extend class IntrinsicCostAttributes to use ElementCount Type

[CarolineConcatto]

Summary

This patch replaces the attribute unsigned VF in the class
IntrinsicCostAttributes by ElementCount VF.
This is a non-functional change to help upcoming patches to compute the cost
model for scalable vector inside this class.

[CarolineConcatto]

-remove non-related changes on Target AMDGPU

[sdesmalen]

Looks like a sensible change to me.

nit: can you please add NFC: in front of the title, like: NFC: Extend class ..., that way people can easily see the patch is NFC and shouldn't cause any side-effects.
nit: the title has the tag [SVE], but there is nothing specific to SVE in this patch, so you can remove it.

llvm/include/llvm/CodeGen/BasicTTIImpl.h

1209–1210

Can you also change unsigned VF and unsigned RetVF to be of type ElementCount?
From what I can see, the changes required for that are quite mechanical, as long as you 'stop' at getOperandsScalarizationOverhead, because that seems like an interface change for another patch.

[CarolineConcatto]

-address review's comment

[CarolineConcatto]

llvm/include/llvm/CodeGen/BasicTTIImpl.h

1209–1210

Thank you Sander.
I've replaced RetVF and VF by ElementCount.
I am using isScalar() where before we had comparing equal to 1 because I imagine that VF will not use a scalable vector (line 1148) and RetVF is not a vector when RetTy->isVectorTy() is false (line 1152).
Like you said I leave getOperandsScalarizationOverhead still using unsigned.

[sdesmalen]

llvm/include/llvm/CodeGen/BasicTTIImpl.h

1212

This can now check for VectorType.

1325

This can now use VectorType::get(OpTy, VF)

1331

This can use VectorType.

[CarolineConcatto]

llvm/include/llvm/CodeGen/BasicTTIImpl.h

1212

This change means that we can now accept scalable vectors, meaning that we will have a functional change. That is not the goal of this patch. I am working on another patch after this that will make the functional change to accept scalable vectors.
I believe it is fine to leave this patch as it is and create another patch that will be able to accept the scalable vector and then add a regression test to validate the change.

[david-arm]

• nit: Can you fix up the formatting issue before merging? Thanks!

llvm/include/llvm/CodeGen/BasicTTIImpl.h

1331

Hi @CarolineConcatto FWIW I think @sdesmalen is right here and you can use VectorType::get and pass in the element count directly. I think this still counts as NFC because the ElementCount will always be for a fixed vector type anyway due to how the ElementCount is created above. However, I think it's fine to leave it like this, since you're fixing this up in a later patch.

[sdesmalen]

LGTM - I thought I already accepted it. I'm happy with having the changes in the other patch.

llvm/include/llvm/Analysis/TargetTransformInfo.h

 
 class IntrinsicCostAttributes {
   const IntrinsicInst *II = nullptr;
   Type *RetTy = nullptr;
   Intrinsic::ID IID;
   SmallVector<Type *, 4> ParamTys;
   SmallVector<const Value *, 4> Arguments;
   FastMathFlags FMF;
-  unsigned VF = 1;
+  ElementCount VF = ElementCount::getFixed(1);
   // If ScalarizationCost is UINT_MAX, the cost of scalarizing the
   // arguments and the return value will be computed based on types.
   unsigned ScalarizationCost = std::numeric_limits<unsigned>::max();
 
 public:
   IntrinsicCostAttributes(const IntrinsicInst &I);
 
   IntrinsicCostAttributes(Intrinsic::ID Id, const CallBase &CI);
 
   IntrinsicCostAttributes(Intrinsic::ID Id, const CallBase &CI,
-                          unsigned Factor);
-  IntrinsicCostAttributes(Intrinsic::ID Id, const CallBase &CI,
-                          ElementCount Factor)
-      : IntrinsicCostAttributes(Id, CI, Factor.getKnownMinValue()) {
-    assert(!Factor.isScalable());
-  }
+                          ElementCount Factor);
 
   IntrinsicCostAttributes(Intrinsic::ID Id, const CallBase &CI,
-                          unsigned Factor, unsigned ScalarCost);
+                          ElementCount Factor, unsigned ScalarCost);
 
   IntrinsicCostAttributes(Intrinsic::ID Id, Type *RTy,
                           ArrayRef<Type *> Tys, FastMathFlags Flags);
 
   IntrinsicCostAttributes(Intrinsic::ID Id, Type *RTy,
                           ArrayRef<Type *> Tys, FastMathFlags Flags,
                           unsigned ScalarCost);
 
   IntrinsicCostAttributes(Intrinsic::ID Id, Type *RTy,
                           ArrayRef<Type *> Tys, FastMathFlags Flags,
                           unsigned ScalarCost,
                           const IntrinsicInst *I);
 
   IntrinsicCostAttributes(Intrinsic::ID Id, Type *RTy,
                           ArrayRef<Type *> Tys);
 
   IntrinsicCostAttributes(Intrinsic::ID Id, Type *RTy,
                           ArrayRef<const Value *> Args);
 
   Intrinsic::ID getID() const { return IID; }
   const IntrinsicInst *getInst() const { return II; }
   Type *getReturnType() const { return RetTy; }
-  unsigned getVectorFactor() const { return VF; }
+  ElementCount getVectorFactor() const { return VF; }
   FastMathFlags getFlags() const { return FMF; }
   unsigned getScalarizationCost() const { return ScalarizationCost; }
   const SmallVectorImpl<const Value *> &getArgs() const { return Arguments; }
   const SmallVectorImpl<Type *> &getArgTypes() const { return ParamTys; }
 
   bool isTypeBasedOnly() const {
     return Arguments.empty();
   }

llvm/include/llvm/CodeGen/BasicTTIImpl.h

unsigned getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
 
     if (ICA.isTypeBasedOnly())
       return getTypeBasedIntrinsicInstrCost(ICA, CostKind);
 
     // TODO: Handle scalable vectors?
     Type *RetTy = ICA.getReturnType();
     if (isa<ScalableVectorType>(RetTy))
       return BaseT::getIntrinsicInstrCost(ICA, CostKind);
 
-    unsigned VF = ICA.getVectorFactor();
-    unsigned RetVF =
-        (RetTy->isVectorTy() ? cast<FixedVectorType>(RetTy)->getNumElements()
-                             : 1);
-    assert((RetVF == 1 || VF == 1) && "VF > 1 and RetVF is a vector type");
+    ElementCount VF = ICA.getVectorFactor();
+    ElementCount RetVF =
+        (RetTy->isVectorTy() ? cast<FixedVectorType>(RetTy)->getElementCount()
+                             : ElementCount::getFixed(1));
+    assert((RetVF.isScalar() || VF.isScalar()) &&
+           "VF > 1 and RetVF is a vector type");
     const IntrinsicInst *I = ICA.getInst();
     const SmallVectorImpl<const Value *> &Args = ICA.getArgs();
     FastMathFlags FMF = ICA.getFlags();
     switch (IID) {
     default:
       break;
 
     case Intrinsic::cttz:
       // FIXME: If necessary, this should go in target-specific overrides.
-      if (VF == 1 && RetVF == 1 && getTLI()->isCheapToSpeculateCttz())
+      if (VF.isScalar() && RetVF.isScalar() &&
+          getTLI()->isCheapToSpeculateCttz())
         return TargetTransformInfo::TCC_Basic;
       break;
 
     case Intrinsic::ctlz:
       // FIXME: If necessary, this should go in target-specific overrides.
-      if (VF == 1 && RetVF == 1 && getTLI()->isCheapToSpeculateCtlz())
+      if (VF.isScalar() && RetVF.isScalar() &&
+          getTLI()->isCheapToSpeculateCtlz())
         return TargetTransformInfo::TCC_Basic;
       break;
 
     case Intrinsic::memcpy:
       return thisT()->getMemcpyCost(ICA.getInst());
 
     case Intrinsic::masked_scatter: {
-      assert(VF == 1 && "Can't vectorize types here.");
+      assert(VF.isScalar() && "Can't vectorize types here.");
       const Value *Mask = Args[3];
       bool VarMask = !isa<Constant>(Mask);
       Align Alignment = cast<ConstantInt>(Args[2])->getAlignValue();
       return thisT()->getGatherScatterOpCost(Instruction::Store,
                                              Args[0]->getType(), Args[1],
                                              VarMask, Alignment, CostKind, I);
     }
     case Intrinsic::masked_gather: {
-      assert(VF == 1 && "Can't vectorize types here.");
+      assert(VF.isScalar() && "Can't vectorize types here.");
       const Value *Mask = Args[2];
       bool VarMask = !isa<Constant>(Mask);
       Align Alignment = cast<ConstantInt>(Args[1])->getAlignValue();
       return thisT()->getGatherScatterOpCost(Instruction::Load, RetTy, Args[0],
                                              VarMask, Alignment, CostKind, I);
     }
     case Intrinsic::vector_reduce_add:
     case Intrinsic::vector_reduce_mul:
case Intrinsic::fshr: {
       return Cost;
     }
     }
 
     // Assume that we need to scalarize this intrinsic.
     SmallVector<Type *, 4> Types;
     for (const Value *Op : Args) {
       Type *OpTy = Op->getType();
-      assert(VF == 1 || !OpTy->isVectorTy());
-      Types.push_back(VF == 1 ? OpTy : FixedVectorType::get(OpTy, VF));
+      assert(VF.isScalar() || !OpTy->isVectorTy());
+      Types.push_back(VF.isScalar()
+                          ? OpTy
+                          : FixedVectorType::get(OpTy, VF.getKnownMinValue()));
     }
 
-    if (VF > 1 && !RetTy->isVoidTy())
-      RetTy = FixedVectorType::get(RetTy, VF);
+    if (VF.isVector() && !RetTy->isVoidTy())
+      RetTy = FixedVectorType::get(RetTy, VF.getKnownMinValue());
 
     // Compute the scalarization overhead based on Args for a vector
     // intrinsic. A vectorizer will pass a scalar RetTy and VF > 1, while
     // CostModel will pass a vector RetTy and VF is 1.
     unsigned ScalarizationCost = std::numeric_limits<unsigned>::max();
-    if (RetVF > 1 || VF > 1) {
+    if (RetVF.isVector() || VF.isVector()) {
       ScalarizationCost = 0;
       if (!RetTy->isVoidTy())
         ScalarizationCost +=
             getScalarizationOverhead(cast<VectorType>(RetTy), true, false);
-      ScalarizationCost += getOperandsScalarizationOverhead(Args, VF);
+      ScalarizationCost +=
+          getOperandsScalarizationOverhead(Args, VF.getKnownMinValue());
     }
 
     IntrinsicCostAttributes Attrs(IID, RetTy, Types, FMF, ScalarizationCost, I);
     return thisT()->getTypeBasedIntrinsicInstrCost(Attrs, CostKind);
   }
 
   /// Get intrinsic cost based on argument types.
   /// If ScalarizationCostPassed is std::numeric_limits<unsigned>::max(), the

llvm/lib/Analysis/TargetTransformInfo.cpp

IntrinsicCostAttributes::IntrinsicCostAttributes(Intrinsic::ID Id,
   Arguments.insert(Arguments.begin(), CI.arg_begin(), CI.arg_end());
   FunctionType *FTy =
     CI.getCalledFunction()->getFunctionType();
   ParamTys.insert(ParamTys.begin(), FTy->param_begin(), FTy->param_end());
 }
 
 IntrinsicCostAttributes::IntrinsicCostAttributes(Intrinsic::ID Id,
                                                  const CallBase &CI,
-                                                 unsigned Factor) :
-    RetTy(CI.getType()), IID(Id), VF(Factor) {
+                                                 ElementCount Factor)
+    : RetTy(CI.getType()), IID(Id), VF(Factor) {
 
+  assert(!Factor.isScalable() && "Scalable vectors are not yet supported");
   if (auto *FPMO = dyn_cast<FPMathOperator>(&CI))
     FMF = FPMO->getFastMathFlags();
 
   Arguments.insert(Arguments.begin(), CI.arg_begin(), CI.arg_end());
   FunctionType *FTy =
     CI.getCalledFunction()->getFunctionType();
   ParamTys.insert(ParamTys.begin(), FTy->param_begin(), FTy->param_end());
 }
 
 IntrinsicCostAttributes::IntrinsicCostAttributes(Intrinsic::ID Id,
                                                  const CallBase &CI,
-                                                 unsigned Factor,
-                                                 unsigned ScalarCost) :
-    RetTy(CI.getType()), IID(Id), VF(Factor), ScalarizationCost(ScalarCost) {
+                                                 ElementCount Factor,
+                                                 unsigned ScalarCost)
+    : RetTy(CI.getType()), IID(Id), VF(Factor), ScalarizationCost(ScalarCost) {
 
   if (const auto *FPMO = dyn_cast<FPMathOperator>(&CI))
     FMF = FPMO->getFastMathFlags();
 
   Arguments.insert(Arguments.begin(), CI.arg_begin(), CI.arg_end());
   FunctionType *FTy =
     CI.getCalledFunction()->getFunctionType();
   ParamTys.insert(ParamTys.begin(), FTy->param_begin(), FTy->param_end());

llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp

if (!OrigTy.isSimple()) {
     if (CostKind != TTI::TCK_CodeSize)
       return BaseT::getIntrinsicInstrCost(ICA, CostKind);
 
     // TODO: Combine these two logic paths.
     if (ICA.isTypeBasedOnly())
       return getTypeBasedIntrinsicInstrCost(ICA, CostKind);
 
     Type *RetTy = ICA.getReturnType();
-    unsigned VF = ICA.getVectorFactor();
+    unsigned VF = ICA.getVectorFactor().getFixedValue();
     unsigned RetVF =
         (RetTy->isVectorTy() ? cast<FixedVectorType>(RetTy)->getNumElements()
                              : 1);
     assert((RetVF == 1 || VF == 1) && "VF > 1 and RetVF is a vector type");
     const IntrinsicInst *I = ICA.getInst();
     const SmallVectorImpl<const Value *> &Args = ICA.getArgs();
     FastMathFlags FMF = ICA.getFlags();
     // Assume that we need to scalarize this intrinsic.

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

 }
 
 static std::pair<unsigned, unsigned>
 getVectorCallCosts(CallInst *CI, FixedVectorType *VecTy,
                    TargetTransformInfo *TTI, TargetLibraryInfo *TLI) {
   Intrinsic::ID ID = getVectorIntrinsicIDForCall(CI, TLI);
 
   // Calculate the cost of the scalar and vector calls.
-  IntrinsicCostAttributes CostAttrs(ID, *CI, VecTy->getNumElements());
+  IntrinsicCostAttributes CostAttrs(ID, *CI, VecTy->getElementCount());
   int IntrinsicCost =
     TTI->getIntrinsicInstrCost(CostAttrs, TTI::TCK_RecipThroughput);
 
   auto Shape = VFShape::get(*CI, ElementCount::getFixed(static_cast<unsigned>(
                                      VecTy->getNumElements())),
                             false /*HasGlobalPred*/);
   Function *VecFunc = VFDatabase(*CI).getVectorizedFunction(Shape);
   int LibCost = IntrinsicCost;
case Instruction::Store: {
       LLVM_DEBUG(dumpTreeCosts(E, ReuseShuffleCost, VecStCost, ScalarStCost));
       return ReuseShuffleCost + VecStCost - ScalarStCost;
     }
     case Instruction::Call: {
       CallInst *CI = cast<CallInst>(VL0);
       Intrinsic::ID ID = getVectorIntrinsicIDForCall(CI, TLI);
 
       // Calculate the cost of the scalar and vector calls.
-      IntrinsicCostAttributes CostAttrs(ID, *CI, 1, 1);
+      IntrinsicCostAttributes CostAttrs(ID, *CI, ElementCount::getFixed(1), 1);
       int ScalarEltCost = TTI->getIntrinsicInstrCost(CostAttrs, CostKind);
       if (NeedToShuffleReuses) {
         ReuseShuffleCost -= (ReuseShuffleNumbers - VL.size()) * ScalarEltCost;
       }
       int ScalarCallCost = VecTy->getNumElements() * ScalarEltCost;
 
       auto VecCallCosts = getVectorCallCosts(CI, VecTy, TTI, TLI);
       int VecCallCost = std::min(VecCallCosts.first, VecCallCosts.second);