[SVE] Make ElementCount members private

[david-arm]

Summary

This patch changes ElementCount so that the Min and Scalable
members are now private and can only be accessed via the get
functions getKnownMinValue() and isScalable(). This is now inline
with the TypeSize class.

In addition I've added some other member functions for more
commonly used operations. Hopefully this makes the class more
useful and will reduce the need for calling getKnownMinValue().

[fpetrogalli]

llvm/include/llvm/Support/TypeSize.h

61

I think that @ctetreau is right on https://reviews.llvm.org/D85794#inline-793909. We should not overload a comparison operator on this class because the set it represent it cannot be ordered.

Chris suggests an approach of writing a static function that can be used as a comparison operator, so that we can make it explicit of what kind of comparison we are doing.

[ctetreau]

Perhaps now would be a good time to combine TypeSize and ElementCount into a single Polynomial type? We don't have to implement the whole abstraction of c*x^n (since we currently don't use the exponent, and don't distinguish between X's) but if it's ever needed in the future it will be obvious where to add it, and it will Just Work.

llvm/include/llvm/Support/TypeSize.h

61

In C++, it's common to overload the comparison operators for the purposes of being able to std::sort and use ordered sets. Normally, I would be OK with such usages. However, since ElementCount is basically a numeric type, and they only have a partial ordering, I think this is dangerous. I'm concerned that this will result in more bugs whereby somebody didn't remember that vectors can be scalable.

I don't have a strong opinion what the comparator function should be called, but I strongly prefer that it not be a comparison operator.

345–347

NIT: this can be rewritten without duplicating EltCnt.getKnownMinValue() * 37U

llvm/lib/Target/AArch64/AArch64ISelLowering.cpp

3548

What is this >> thing? Some indicator of whitespace change, or is this a hard tab?

[efriedma]

Perhaps now would be a good time to combine TypeSize and ElementCount into a single Polynomial type? We don't have to implement the whole abstraction of c*x^n (since we currently don't use the exponent, and don't distinguish between X's) but if it's ever needed in the future it will be obvious where to add it, and it will Just Work.

Even if the types are structurally similar, I'd prefer to keep them separate. The uses are distinct, the usage in a function signature indicates what kind of value we actually expect. (It's particularly easy to perform incorrect conversions with types representing size and alignment.)

llvm/lib/Target/AArch64/AArch64ISelLowering.cpp

3548

It's an indicator of a whitespace change; I think they started showing up with the recent Phabricator upgrade

[david-arm]

Hi @ctetreau, I agree with @efriedma that keeping the two classes distinct for now seems best. The reason is I spent quite a lot of time trying to unify these classes already and I hit a stumbling block - TypeSize has the ugly uint64_t() cast operator, which makes unifying difficult. I didn't want to introduce a templated cast operator that ElementCount would then have too. I also tried making TypeSize derive from a templated parent, but that was pretty ugly too. Perhaps once we've removed the TypeSize -> uint64_t we might be better able to consider it?

llvm/include/llvm/Support/TypeSize.h

61

Hi @ctetreau, yeah I understand. The reason I chose to use operators was simply to be consistent with what we have already in TypeSize. Also, we have existing "==" and "!=" operators in ElementCount too, although these are essentially testing that two ElementCounts are identically the same or not, i.e. for 2 given polynomials (a + bx) and (c + dx) we're essentially asking if both a==c and b==d.

If I introduce a new comparison function, I'll probably keep the asserts in for now, but in general we can do better than simply asserting if something is scalable or not. For example, we know that (vscale * 4) is definitely >= 4 because vscale is at least 1. I'm just not sure if we have that need yet.

[paulwalker-arm]

llvm/include/llvm/Support/TypeSize.h

61

I think we should treat the non-equality comparison functions more like floating point. What we don't want is somebody writing !GreaterThan when they actually mean LessThan.

Perhaps we should name the functions accordingly (i.e. ogt for OrderedAndGreaterThan). We will also need matching less than functions since I can see those being useful when analysing constant insert/extract element indices which stand a good chance to be a known comparison (with 0 being the most common index).

[fpetrogalli]

llvm/include/llvm/Support/TypeSize.h

61

May I suggest the following name scheme? (my 2 c, will not hold the patch for not addressing this comment)

static bool [Non]Total<cmp>(...)

with <cmp> being

• LT -> less than, aka <
• LToE -> less than or equal, aka "<="
• GT -> greater than, aka ">"
• GToE -> greater than or equal, aka ">="

and Total , NonTotal being the prefix that gives information about the behavior on the value of scalable:

Total -> for example, all scalable ECs are bigger than fixed ECs.
NonTotal -> asserting on (LHS.Scalable == RHS.Scalable) before returning LHS.Min <cmp> RHS.Min.

Taking it further: it could also be a template on an enumeration that list the type of comparisons?

enum CMPType {
  TotalGT,
  NonTotalLT,
  fancy_one
};

...

template <unsigned T>
static bool cmp(ElementCount &LHS, ElementCount &RHS );

...

static bool ElementCount::cmp<ElementCount::CMPType::TotalGT>(ElementCount &LHS, ElementCount &RHS ) {
 /// implementation
}
static bool ElementCount::cmp<ElementCount::CMPType::fancy_one>(ElementCount &LHS, ElementCount &RHS ) {
 /// implementation
}

[david-arm]

Hi @fpetrogalli, if you don't mind I think I'll stick with Paul's idea for ogt because this matches the IR neatly, i.e. "fcmp ogt". Also, for me personally it's much simpler and more intuitive.

[fpetrogalli]

In D86065#2235434, @david-arm wrote:

Hi @fpetrogalli, if you don't mind I think I'll stick with Paul's idea for ogt because this matches the IR neatly, i.e. "fcmp ogt". Also, for me personally it's much simpler and more intuitive.

I don't mind at all, please follow Paul's suggestion, mine was just an alternative. Thanks!

[david-arm]

• Changed comparison function from gt to ogt and added a olt (less than) comparison function too.
• Instead of adding the ">>=" operator I've added "/=" instead as I think this is more common. In places where ">>= 1" was used we now do "/= 2".
• After rebasing it was necessary to add a "*=" operator too for the Loop Vectorizer.

[ctetreau]

llvm/include/llvm/Support/TypeSize.h

61

Honestly, I think this is actually worse. My issue is the fact that, from a mathematical perspective, vscale_1 * min_1 < vscale_2 * min_2 is a function of vscale_1 and vscale_2. In principle, we can know some ordering relationships between certain element counts (such as vscale * min_1 >= min_2 = true), but in general, this function does not make sense. However, an operator< is useful because it allows you to put an ElementCount into an ordered set, and it will just work. Renaming the function to olt just makes it so that you can't put ElementCounts into an ordered set, but still implies that ElementCounts are comparable in general. This will also blow up if you actually try to mix fixed width and scalable ElementCounts in an ordered set, which should work IMO.

Here is what I propose:

1. Add a predicate for establishing an arbitrary ordering. The predicate would be completely arbitrary, because it's only useful for establishing an ordering for an ordered set or in a sorting algorithm. It could look something like this:

static bool orderedBefore(const ElementCount &LHS, const ElementCount &RHS) {
  auto l = std::tie(LHS.Scalable, LHS.Min);
  auto r = std::tie(RHS.Scalable, RHS.Min);
  return l < r;
}

2. don't add any sort of mathematical comparison functions. Code working with ElementCount almost certainly either inspects the Scalable field and does something with the Min:

if (EC.isScalable()) {
    unsigned min = EC.getKnownMinValue();
    ... // do stuff with min

... or just uses it as a unit:

auto * VecTy = VectorType::get(SomeTy, EC);

I do not think that having the relation operators on ElementCount would simplify very much code. However, it is very easy to use incorrectly, and if it is ever extended in the future (one machine with two different vscale values? vscale == 0 becoming valid?), it would become even worse. Best just not open that door.

[david-arm]

Hi @ctetreau, ok for now I'm going to completely remove the operators and revert the code using those operators to how it was before. I'm not sure what you mean about the predicate functions so I've left those for now, since they aren't needed for this patch. The purpose of this patch was originally supposed to be mechanical anyway - just making members private. I only added the operators as an after-thought really, just to be consistent with how TypeSize dealt with the identical problem. For what it's worth, I believe that GCC solved this exact same problem by adding two types of comparison functions - one set that absolutely wanted an answer to ">,<,>=,<=" and asserted if it wasn't known at compile time, and another set of comparison functions that returned an additional boolean value indicating whether the answer was known or not. Perhaps my knowledge is out of date, but I believe this was the accepted solution and seemed to work well.

[paulwalker-arm]

llvm/include/llvm/Support/TypeSize.h

114

I don't believe this is safe. For example we know SVE supported vector lengths only have to be a multiple of 128bits. So for scalable vectors we cannot know the element count is a power of 2 unless we perform a runtime check.

[david-arm]

llvm/include/llvm/Support/TypeSize.h

114

Ok, but if that's true how is code in llvm/lib/CodeGen/TargetLoweringBase.cpp ever safe for scalable vectors? I thought that the question being asked wasn't that the total size was a power of 2, but whether or not it was safe to split the vector. The answer should be the same even if vscale is 3, for example. I thought the problem here is that the legaliser simply needs to know in what way it should break down different types, and that whatever approach it took would work when scaled up. The vector breakdown algorithm relies upon having an answer here - perhaps this is just a case of changing the question and name of function?

[paulwalker-arm]

I cannot say whether such questions make sense without a deeper investigation, but I can say for certain that EC.isPowerOf2 is a question we cannot answer at compile time. Given this is a mechanical change I would just remove the member function and leave the code as is (well change EC.Min to EC.getKnownMinValue()). We already know that we'll need to visit the places where getKnownMinValue() is used to ensure the question makes sense in the face of scalable vectors.

[david-arm]

• Removed isPowerOf2() function since this is potentially misleading - it's only the known minimum value that we're checking.
• Renamed isEven to isKnownEven to try and make it clear that returning true indicates we know definitely that the total number of elements is even, whereas returning false could mean either the element count is odd or that we don't know.

[paulwalker-arm]

There's probably a few .Min to .getKnownMinValue() conversions where the .Min could be dropped (calls to Builder.CreateVectorSplat for example) but they can be tidied up as part of a proper activity to reduce the places where getKnownMinValue is called. So other than my suggested updated to EC::operator/ the patch looks good to my eye. Please give other reviewers a little more time to provide other insights.

llvm/include/llvm/Support/TypeSize.h

66

If you add an assert that the divide is lossless (i.e. MIN % RHS == 0) then asserts like:

assert(EltCnt.isKnownEven() && "Splitting vector, but not in half!");

are no longer required. Plus those places which are not checking for lossless division will be automatically protected. This feels like a sensible default to me. If somebody wants a truncated result, they can do the maths using getKnownMinValue().

[ctetreau]

In D86065#2241146, @david-arm wrote:

Hi @ctetreau, ok for now I'm going to completely remove the operators and revert the code using those operators to how it was before. ...

This is probably for the best.

In D86065#2241146, @david-arm wrote:

... I'm not sure what you mean about the predicate functions ...

I'm referring to providing some built in way to std::sort a collection of ElementCount or have a std::set<ElementCount>. By default, C++ wants to use operator< for this, which I believe was the original motivation for the operator being here in the first place. I think it's reasonable for ElementCount to provide a built-in function to establish an ordering for these purposes, but the function should be named such that nobody thinks the function is intended to be the mathematical relation.

[ctetreau]

I think this is good to go as is. Assuming @paulwalker-arm is satisfied with leaving operator/ as is, then LGTM.

llvm/include/llvm/Support/TypeSize.h

66

I would prefer that this not be done. This would make this function non-total in an unrecoverable way, and would force everybody to write a bunch of tedious error handling code, even if the normal integer division behavior would have been fine:

ElementCount res = LHS.getKnownMinValue() % RHS.getKnownMinValue() == 0 ? LHS / RHS : SomeOtherThing;

Everybody knows how integer division works, so I think the lossy behavior will not surprise anybody. An assert might.

[paulwalker-arm]

Can't say I agree since people are already writing the ugly code, because the result typically demands different handling or they're asserting the divide doesn't truncate in the first place. That said I'm happy for there to be no assert as long as operator% is implemented so users can calculate the remainder in the expected way.

[paulwalker-arm]

I'm retracting my operator% request. After thinking about it and speaking with Dave I just cannot see how allowing a total divide is safe for scalable vectors. If you are relying on a truncating divide then special handling is require anyway, which is likely to be different between fixed-length and scalable vectors.

[paulwalker-arm]

To be more clear, I'm happy to defer the divide conversation for if/when we run into issues so my previous acceptance still stands. It'll be good to get the intent of the patch in (i.e. stoping access to internal class members) asap, plus any follow up work will be a smaller more manageable patch. It's worth talking this through during the next sync call to see it we can get some consensus regarding what maths is and isn't allowed.

[rsandifo-arm]

In D86065#2241146, @david-arm wrote:

Hi @ctetreau, ok for now I'm going to completely remove the operators and revert the code using those operators to how it was before. I'm not sure what you mean about the predicate functions so I've left those for now, since they aren't needed for this patch. The purpose of this patch was originally supposed to be mechanical anyway - just making members private. I only added the operators as an after-thought really, just to be consistent with how TypeSize dealt with the identical problem. For what it's worth, I believe that GCC solved this exact same problem by adding two types of comparison functions - one set that absolutely wanted an answer to ">,<,>=,<=" and asserted if it wasn't known at compile time, and another set of comparison functions that returned an additional boolean value indicating whether the answer was known or not. Perhaps my knowledge is out of date, but I believe this was the accepted solution and seemed to work well.

FWIW, the GCC scheme is to have one set of functions maybe_<cond> that are true if a condition *might* hold (i.e. would hold for one possible value of the runtime indeterminates), and another set of functions known_<cond> (originally must_<cond>) that are true if a condition *always* holds (i.e. would hold for all possible values of the runtime indeterminates). known_le is a partial order but maybe_le is not (because it isn't antisymmetric). Having both is redundant with !, since e.g. known_le is the opposite of maybe_gt, but it seemed more readable to allow every condition to be expressed positively.

Like you say, there is also a test for whether two values are ordered by known_le, and there are also some operations like ordered_min and ordered_max that assert if the values aren't ordered by known_le.

[Sorry for the post-commit comment, but it's related to something that wasn't part of the commit.]

clang/lib/CodeGen/CGBuiltin.cpp

Value *CodeGenFunction::EmitAArch64SVEBuiltinExpr(unsigned BuiltinID,
   case SVE::BI__builtin_sve_svlen_s32:
   case SVE::BI__builtin_sve_svlen_s64:
   case SVE::BI__builtin_sve_svlen_u8:
   case SVE::BI__builtin_sve_svlen_u16:
   case SVE::BI__builtin_sve_svlen_u32:
   case SVE::BI__builtin_sve_svlen_u64: {
     SVETypeFlags TF(Builtin->TypeModifier);
     auto VTy = cast<llvm::VectorType>(getSVEType(TF));
-    auto NumEls = llvm::ConstantInt::get(Ty, VTy->getElementCount().Min);
+    auto *NumEls =
+        llvm::ConstantInt::get(Ty, VTy->getElementCount().getKnownMinValue());
 
     Function *F = CGM.getIntrinsic(Intrinsic::vscale, Ty);
     return Builder.CreateMul(NumEls, Builder.CreateCall(F));
   }
 
   case SVE::BI__builtin_sve_svtbl2_u8:
   case SVE::BI__builtin_sve_svtbl2_s8:
   case SVE::BI__builtin_sve_svtbl2_u16:

clang/lib/CodeGen/CGDebugInfo.cpp

case BuiltinType::Id: \
     return getOrCreateStructPtrType("opencl_" #ExtType, Id##Ty);
 #include "clang/Basic/OpenCLExtensionTypes.def"
 
 #define SVE_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
 #include "clang/Basic/AArch64SVEACLETypes.def"
     {
       ASTContext::BuiltinVectorTypeInfo Info =
           CGM.getContext().getBuiltinVectorTypeInfo(BT);
-      unsigned NumElemsPerVG = (Info.EC.Min * Info.NumVectors) / 2;
+      unsigned NumElemsPerVG = (Info.EC.getKnownMinValue() * Info.NumVectors) / 2;
 
       // Debuggers can't extract 1bit from a vector, so will display a
       // bitpattern for svbool_t instead.
       if (Info.ElementType == CGM.getContext().BoolTy) {
         NumElemsPerVG /= 8;
         Info.ElementType = CGM.getContext().UnsignedCharTy;
       }
 

clang/lib/CodeGen/CodeGenTypes.cpp

#include "clang/Basic/OpenCLExtensionTypes.def"
     case BuiltinType::SveFloat64x4:
     case BuiltinType::SveBFloat16:
     case BuiltinType::SveBFloat16x2:
     case BuiltinType::SveBFloat16x3:
     case BuiltinType::SveBFloat16x4: {
       ASTContext::BuiltinVectorTypeInfo Info =
           Context.getBuiltinVectorTypeInfo(cast<BuiltinType>(Ty));
       return llvm::ScalableVectorType::get(ConvertType(Info.ElementType),
-                                           Info.EC.Min * Info.NumVectors);
+                                           Info.EC.getKnownMinValue() *
+                                               Info.NumVectors);
     }
     case BuiltinType::Dependent:
 #define BUILTIN_TYPE(Id, SingletonId)
 #define PLACEHOLDER_TYPE(Id, SingletonId) \
     case BuiltinType::Id:
 #include "clang/AST/BuiltinTypes.def"
       llvm_unreachable("Unexpected placeholder builtin type!");
     }

llvm/include/llvm/Analysis/TargetTransformInfo.h

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.Min) {
-    assert(!Factor.Scalable);
+      : IntrinsicCostAttributes(Id, CI, Factor.getKnownMinValue()) {
+    assert(!Factor.isScalable());
   }
 
   IntrinsicCostAttributes(Intrinsic::ID Id, const CallBase &CI,
                           unsigned Factor, unsigned ScalarCost);
 
   IntrinsicCostAttributes(Intrinsic::ID Id, Type *RTy,
                           ArrayRef<Type *> Tys, FastMathFlags Flags);
 

llvm/include/llvm/Analysis/VectorUtils.h

struct VFShape {
   static VFShape get(const CallInst &CI, ElementCount EC, bool HasGlobalPred) {
     SmallVector<VFParameter, 8> Parameters;
     for (unsigned I = 0; I < CI.arg_size(); ++I)
       Parameters.push_back(VFParameter({I, VFParamKind::Vector}));
     if (HasGlobalPred)
       Parameters.push_back(
           VFParameter({CI.arg_size(), VFParamKind::GlobalPredicate}));
 
-    return {EC.Min, EC.Scalable, Parameters};
+    return {EC.getKnownMinValue(), EC.isScalable(), Parameters};
   }
   /// Sanity check on the Parameters in the VFShape.
   bool hasValidParameterList() const;
 };
 
 /// Holds the VFShape for a specific scalar to vector function mapping.
 struct VFInfo {
   VFShape Shape;          /// Classification of the vector function.

llvm/include/llvm/CodeGen/ValueTypes.h

ElementCount getVectorElementCount() const {
       if (isSimple())
         return V.getVectorElementCount();
 
       return getExtendedVectorElementCount();
     }
 
     /// Given a vector type, return the minimum number of elements it contains.
     unsigned getVectorMinNumElements() const {
-      return getVectorElementCount().Min;
+      return getVectorElementCount().getKnownMinValue();
     }
 
     /// Return the size of the specified value type in bits.
     ///
     /// If the value type is a scalable vector type, the scalable property will
     /// be set and the runtime size will be a positive integer multiple of the
     /// base size.
     TypeSize getSizeInBits() const {
#endif
     }
 
     // Return a VT for a vector type with the same element type but
     // half the number of elements. The type returned may be an
     // extended type.
     EVT getHalfNumVectorElementsVT(LLVMContext &Context) const {
       EVT EltVT = getVectorElementType();
       auto EltCnt = getVectorElementCount();
-      assert(!(EltCnt.Min & 1) && "Splitting vector, but not in half!");
+      assert(EltCnt.isKnownEven() && "Splitting vector, but not in half!");
       return EVT::getVectorVT(Context, EltVT, EltCnt / 2);
     }
 
     /// Returns true if the given vector is a power of 2.
     bool isPow2VectorType() const {
       unsigned NElts = getVectorMinNumElements();
       return !(NElts & (NElts - 1));
     }
 
     /// Widens the length of the given vector EVT up to the nearest power of 2
     /// and returns that type.
     EVT getPow2VectorType(LLVMContext &Context) const {
       if (!isPow2VectorType()) {
         ElementCount NElts = getVectorElementCount();
-        NElts.Min = 1 << Log2_32_Ceil(NElts.Min);
+        unsigned NewMinCount = 1 << Log2_32_Ceil(NElts.getKnownMinValue());
+        NElts = ElementCount::get(NewMinCount, NElts.isScalable());
         return EVT::getVectorVT(Context, getVectorElementType(), NElts);
       }
       else {
         return *this;
       }
     }
 
     /// This function returns value type as a string, e.g. "i32".

llvm/include/llvm/IR/DataLayout.h

inline TypeSize DataLayout::getTypeSizeInBits(Type *Ty) const {
   // In memory objects this is always aligned to a higher boundary, but
   // only 80 bits contain information.
   case Type::X86_FP80TyID:
     return TypeSize::Fixed(80);
   case Type::FixedVectorTyID:
   case Type::ScalableVectorTyID: {
     VectorType *VTy = cast<VectorType>(Ty);
     auto EltCnt = VTy->getElementCount();
-    uint64_t MinBits = EltCnt.Min *
-                        getTypeSizeInBits(VTy->getElementType()).getFixedSize();
-    return TypeSize(MinBits, EltCnt.Scalable);
+    uint64_t MinBits = EltCnt.getKnownMinValue() *
+    return TypeSize(MinBits, EltCnt.isScalable());
   }
   default:
     llvm_unreachable("DataLayout::getTypeSizeInBits(): Unsupported type");
   }
 }
 
 } // end namespace llvm
 
 #endif // LLVM_IR_DATALAYOUT_H

llvm/include/llvm/IR/DerivedTypes.h

public:
   VectorType &operator=(const VectorType &) = delete;
 
   /// Get the number of elements in this vector. It does not make sense to call
   /// this function on a scalable vector, and this will be moved into
   /// FixedVectorType in a future commit
   unsigned getNumElements() const {
     ElementCount EC = getElementCount();
 #ifdef STRICT_FIXED_SIZE_VECTORS
-    assert(!EC.Scalable &&
+    assert(!EC.isScalable() &&
            "Request for fixed number of elements from scalable vector");
-    return EC.Min;
+    return EC.getKnownMinValue();
 #else
-    if (EC.Scalable)
+    if (EC.isScalable())
       WithColor::warning()
           << "The code that requested the fixed number of elements has made "
              "the assumption that this vector is not scalable. This assumption "
              "was not correct, and this may lead to broken code\n";
-    return EC.Min;
+    return EC.getKnownMinValue();
 #endif
   }
 
   Type *getElementType() const { return ContainedType; }
 
   /// This static method is the primary way to construct an VectorType.
   static VectorType *get(Type *ElementType, ElementCount EC);
 
static VectorType *getSubdividedVectorType(VectorType *VTy, int NumSubdivs) {
     }
     return VTy;
   }
 
   /// This static method returns a VectorType with half as many elements as the
   /// input type and the same element type.
   static VectorType *getHalfElementsVectorType(VectorType *VTy) {
     auto EltCnt = VTy->getElementCount();
-    assert ((EltCnt.Min & 1) == 0 &&
-            "Cannot halve vector with odd number of elements.");
+    assert(EltCnt.isKnownEven() &&
     return VectorType::get(VTy->getElementType(), EltCnt/2);
   }
 
   /// This static method returns a VectorType with twice as many elements as the
   /// input type and the same element type.
   static VectorType *getDoubleElementsVectorType(VectorType *VTy) {
     auto EltCnt = VTy->getElementCount();
-    assert((EltCnt.Min * 2ull) <= UINT_MAX && "Too many elements in vector");
+    assert((EltCnt.getKnownMinValue() * 2ull) <= UINT_MAX &&
+           "Too many elements in vector");
     return VectorType::get(VTy->getElementType(), EltCnt * 2);
   }
 
   /// Return true if the specified type is valid as a element type.
   static bool isValidElementType(Type *ElemTy);
 
   /// Return an ElementCount instance to represent the (possibly scalable)
   /// number of elements in the vector.

llvm/include/llvm/IR/Instructions.h

public:
 
   ArrayRef<int> getShuffleMask() const { return ShuffleMask; }
 
   /// Return true if this shuffle returns a vector with a different number of
   /// elements than its source vectors.
   /// Examples: shufflevector <4 x n> A, <4 x n> B, <1,2,3>
   ///           shufflevector <4 x n> A, <4 x n> B, <1,2,3,4,5>
   bool changesLength() const {
-    unsigned NumSourceElts =
-        cast<VectorType>(Op<0>()->getType())->getElementCount().Min;
+    unsigned NumSourceElts = cast<VectorType>(Op<0>()->getType())
+                                 ->getElementCount()
+                                 .getKnownMinValue();
     unsigned NumMaskElts = ShuffleMask.size();
     return NumSourceElts != NumMaskElts;
   }
 
   /// Return true if this shuffle returns a vector with a greater number of
   /// elements than its source vectors.
   /// Example: shufflevector <2 x n> A, <2 x n> B, <1,2,3>
   bool increasesLength() const {

llvm/include/llvm/Support/MachineValueType.h

bool isOverloaded() const {
               SimpleTy == MVT::iPTRAny);
     }
 
     /// Return a VT for a vector type with the same element type but
     /// half the number of elements.
     MVT getHalfNumVectorElementsVT() const {
       MVT EltVT = getVectorElementType();
       auto EltCnt = getVectorElementCount();
-      assert(!(EltCnt.Min & 1) && "Splitting vector, but not in half!");
+      assert(EltCnt.isKnownEven() && "Splitting vector, but not in half!");
       return getVectorVT(EltVT, EltCnt / 2);
     }
 
     /// Returns true if the given vector is a power of 2.
     bool isPow2VectorType() const {
       unsigned NElts = getVectorNumElements();
       return !(NElts & (NElts - 1));
     }
public:
     }
 
     ElementCount getVectorElementCount() const {
       return ElementCount::get(getVectorNumElements(), isScalableVector());
     }
 
     /// Given a vector type, return the minimum number of elements it contains.
     unsigned getVectorMinNumElements() const {
-      return getVectorElementCount().Min;
+      return getVectorElementCount().getKnownMinValue();
     }
 
     /// Returns the size of the specified MVT in bits.
     ///
     /// If the value type is a scalable vector type, the scalable property will
     /// be set and the runtime size will be a positive integer multiple of the
     /// base size.
     TypeSize getSizeInBits() const {

 
     static MVT getVectorVT(MVT VT, unsigned NumElements, bool IsScalable) {
       if (IsScalable)
         return getScalableVectorVT(VT, NumElements);
       return getVectorVT(VT, NumElements);
     }
 
     static MVT getVectorVT(MVT VT, ElementCount EC) {
-      if (EC.Scalable)
-        return getScalableVectorVT(VT, EC.Min);
-      return getVectorVT(VT, EC.Min);
+      if (EC.isScalable())
+        return getScalableVectorVT(VT, EC.getKnownMinValue());
+      return getVectorVT(VT, EC.getKnownMinValue());
     }
 
     /// Return the value type corresponding to the specified type.  This returns
     /// all pointers as iPTR.  If HandleUnknown is true, unknown types are
     /// returned as Other, otherwise they are invalid.
     static MVT getVT(Type *Ty, bool HandleUnknown = false);
 
   private:

llvm/include/llvm/Support/TypeSize.h

 #include <cassert>
 
 namespace llvm {
 
 template <typename T> struct DenseMapInfo;
 
 class ElementCount {
 private:
+  unsigned Min;  // Minimum number of vector elements.
+  bool Scalable; // If true, NumElements is a multiple of 'Min' determined
+                 // at runtime rather than compile time.
+
   /// Prevent code from using initializer-list contructors like
   /// ElementCount EC = {<unsigned>, <bool>}. The static `get*`
   /// methods below are preferred, as users should always make a
   /// conscious choice on the type of `ElementCount` they are
   /// requesting.
   ElementCount(unsigned Min, bool Scalable) : Min(Min), Scalable(Scalable) {}
 
 public:
-  unsigned Min;  // Minimum number of vector elements.
-  bool Scalable; // If true, NumElements is a multiple of 'Min' determined
-                 // at runtime rather than compile time.
-
   ElementCount() = default;
 
   ElementCount operator*(unsigned RHS) {
     return { Min * RHS, Scalable };
   }
   ElementCount operator/(unsigned RHS) {
     assert(Min % RHS == 0 && "Min is not a multiple of RHS.");
     return { Min / RHS, Scalable };
   }
 
   bool operator==(const ElementCount& RHS) const {
     return Min == RHS.Min && Scalable == RHS.Scalable;
   }
   bool operator!=(const ElementCount& RHS) const {
     return !(*this == RHS);
   }
   bool operator==(unsigned RHS) const { return Min == RHS && !Scalable; }
   bool operator!=(unsigned RHS) const { return !(*this == RHS); }
 
+  ElementCount &operator*=(unsigned RHS) {
+    Min *= RHS;
+    return *this;
+  }
+
+  ElementCount &operator/=(unsigned RHS) {
+    Min /= RHS;
+    return *this;
+  }
+
   ElementCount NextPowerOf2() const {
     return {(unsigned)llvm::NextPowerOf2(Min), Scalable};
   }
 
   static ElementCount getFixed(unsigned Min) { return {Min, false}; }
   static ElementCount getScalable(unsigned Min) { return {Min, true}; }
   static ElementCount get(unsigned Min, bool Scalable) {
     return {Min, Scalable};
   }
 
   /// Printing function.
   void print(raw_ostream &OS) const {
     if (Scalable)
       OS << "vscale x ";
     OS << Min;
   }
   /// Counting predicates.
   ///
   /// Notice that Min = 1 and Scalable = true is considered more than
   /// one element.
   ///
   ///@{ No elements..
   bool isZero() const { return Min == 0; }
+  /// At least one element.
+  bool isNonZero() const { return Min != 0; }
+  /// A return value of true indicates we know at compile time that the number
+  /// of elements (vscale * Min) is definitely even. However, returning false
+  /// does not guarantee that the total number of elements is odd.
+  bool isKnownEven() const { return (Min & 0x1) == 0; }
   /// Exactly one element.
   bool isScalar() const { return !Scalable && Min == 1; }
   /// One or more elements.
   bool isVector() const { return (Scalable && Min != 0) || Min > 1; }
   ///@}
+
+  unsigned getKnownMinValue() const { return Min; }
+
+  bool isScalable() const { return Scalable; }
 };
 
 /// Stream operator function for `ElementCount`.
 inline raw_ostream &operator<<(raw_ostream &OS, const ElementCount &EC) {
   EC.print(OS);
   return OS;
 }
 
 // This class is used to represent the size of types. If the type is of fixed
 // size, it will represent the exact size. If the type is a scalable vector,
 // it will represent the known minimum size.
 class TypeSize {
   uint64_t MinSize;   // The known minimum size.
   bool IsScalable;    // If true, then the runtime size is an integer multiple

 template <> struct DenseMapInfo<ElementCount> {
   static inline ElementCount getEmptyKey() {
     return ElementCount::getScalable(~0U);
   }
   static inline ElementCount getTombstoneKey() {
     return ElementCount::getFixed(~0U - 1);
   }
   static unsigned getHashValue(const ElementCount& EltCnt) {
-    if (EltCnt.Scalable)
-      return (EltCnt.Min * 37U) - 1U;
+    unsigned HashVal = EltCnt.getKnownMinValue() * 37U;
+    if (EltCnt.isScalable())
+      return (HashVal - 1U);
 
-    return EltCnt.Min * 37U;
+    return HashVal;
   }
 
   static bool isEqual(const ElementCount& LHS, const ElementCount& RHS) {
     return LHS == RHS;
   }
 };
 
 } // end namespace llvm
 
 #endif // LLVM_SUPPORT_TypeSize_H

llvm/lib/Analysis/InstructionSimplify.cpp

static Value *SimplifyShuffleVectorInst(Value *Op0, Value *Op1,
                                         unsigned MaxRecurse) {
   if (all_of(Mask, [](int Elem) { return Elem == UndefMaskElem; }))
     return UndefValue::get(RetTy);
 
   auto *InVecTy = cast<VectorType>(Op0->getType());
   unsigned MaskNumElts = Mask.size();
   ElementCount InVecEltCount = InVecTy->getElementCount();
 
-  bool Scalable = InVecEltCount.Scalable;
+  bool Scalable = InVecEltCount.isScalable();
 
   SmallVector<int, 32> Indices;
   Indices.assign(Mask.begin(), Mask.end());
 
   // Canonicalization: If mask does not select elements from an input vector,
   // replace that input vector with undef.
   if (!Scalable) {
     bool MaskSelects0 = false, MaskSelects1 = false;
-    unsigned InVecNumElts = InVecEltCount.Min;
+    unsigned InVecNumElts = InVecEltCount.getKnownMinValue();
     for (unsigned i = 0; i != MaskNumElts; ++i) {
       if (Indices[i] == -1)
         continue;
       if ((unsigned)Indices[i] < InVecNumElts)
         MaskSelects0 = true;
       else
         MaskSelects1 = true;
     }
static Value *SimplifyShuffleVectorInst(Value *Op0, Value *Op1,
   if (Op0Const && Op1Const)
     return ConstantExpr::getShuffleVector(Op0Const, Op1Const, Mask);
 
   // Canonicalization: if only one input vector is constant, it shall be the
   // second one. This transformation depends on the value of the mask which
   // is not known at compile time for scalable vectors
   if (!Scalable && Op0Const && !Op1Const) {
     std::swap(Op0, Op1);
-    ShuffleVectorInst::commuteShuffleMask(Indices, InVecEltCount.Min);
+    ShuffleVectorInst::commuteShuffleMask(Indices,
+                                          InVecEltCount.getKnownMinValue());
   }
 
   // A splat of an inserted scalar constant becomes a vector constant:
   // shuf (inselt ?, C, IndexC), undef, <IndexC, IndexC...> --> <C, C...>
   // NOTE: We may have commuted above, so analyze the updated Indices, not the
   //       original mask constant.
   // NOTE: This transformation depends on the value of the mask which is not
   // known at compile time for scalable vectors

llvm/lib/Analysis/VFABIDemangling.cpp

Optional<VFInfo> VFABI::tryDemangleForVFABI(StringRef MangledName,
   // set to 0.
   if (IsScalable) {
     const Function *F = M.getFunction(VectorName);
     // The declaration of the function must be present in the module
     // to be able to retrieve its signature.
     if (!F)
       return None;
     const ElementCount EC = getECFromSignature(F->getFunctionType());
-    VF = EC.Min;
+    VF = EC.getKnownMinValue();
   }
 
   // Sanity checks.
   // 1. We don't accept a zero lanes vectorization factor.
   // 2. We don't accept the demangling if the vector function is not
   // present in the module.
   if (VF == 0)
     return None;

llvm/lib/Analysis/ValueTracking.cpp

case Instruction::Invoke: {
     return !CB->hasRetAttr(Attribute::NoUndef);
   }
   case Instruction::InsertElement:
   case Instruction::ExtractElement: {
     // If index exceeds the length of the vector, it returns poison
     auto *VTy = cast<VectorType>(Op->getOperand(0)->getType());
     unsigned IdxOp = Op->getOpcode() == Instruction::InsertElement ? 2 : 1;
     auto *Idx = dyn_cast<ConstantInt>(Op->getOperand(IdxOp));
-    if (!Idx || Idx->getZExtValue() >= VTy->getElementCount().Min)
+    if (!Idx ||
+        Idx->getZExtValue() >= VTy->getElementCount().getKnownMinValue())
       return true;
     return false;
   }
   case Instruction::ShuffleVector: {
     // shufflevector may return undef.
     if (PoisonOnly)
       return false;
     ArrayRef<int> Mask = isa<ConstantExpr>(Op)

llvm/lib/Bitcode/Writer/BitcodeWriter.cpp

case Type::ArrayTyID: {
       break;
     }
     case Type::FixedVectorTyID:
     case Type::ScalableVectorTyID: {
       VectorType *VT = cast<VectorType>(T);
       // VECTOR [numelts, eltty] or
       //        [numelts, eltty, scalable]
       Code = bitc::TYPE_CODE_VECTOR;
-      TypeVals.push_back(VT->getElementCount().Min);
+      TypeVals.push_back(VT->getElementCount().getKnownMinValue());
       TypeVals.push_back(VE.getTypeID(VT->getElementType()));
       if (isa<ScalableVectorType>(VT))
         TypeVals.push_back(true);
       break;
     }
     }
 
     // Emit the finished record.

llvm/lib/CodeGen/CodeGenPrepare.cpp

if (!UseSplat) {
       else
         UseSplat = true;
     }
 
     ElementCount EC = cast<VectorType>(getTransitionType())->getElementCount();
     if (UseSplat)
       return ConstantVector::getSplat(EC, Val);
 
-    if (!EC.Scalable) {
+    if (!EC.isScalable()) {
       SmallVector<Constant *, 4> ConstVec;
       UndefValue *UndefVal = UndefValue::get(Val->getType());
-      for (unsigned Idx = 0; Idx != EC.Min; ++Idx) {
+      for (unsigned Idx = 0; Idx != EC.getKnownMinValue(); ++Idx) {
         if (Idx == ExtractIdx)
           ConstVec.push_back(Val);
         else
           ConstVec.push_back(UndefVal);
       }
       return ConstantVector::get(ConstVec);
     } else
       llvm_unreachable(

llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

for (SDValue Op : N->ops()) {
     SrcOps.push_back(Op.getOperand(0));
   }
 
   // The wider cast must be supported by the target. This is unusual because
   // the operation support type parameter depends on the opcode. In addition,
   // check the other type in the cast to make sure this is really legal.
   EVT VT = N->getValueType(0);
   EVT SrcEltVT = SrcVT.getVectorElementType();
-  unsigned NumElts = SrcVT.getVectorElementCount().Min * N->getNumOperands();
+  ElementCount NumElts = SrcVT.getVectorElementCount() * N->getNumOperands();
   EVT ConcatSrcVT = EVT::getVectorVT(*DAG.getContext(), SrcEltVT, NumElts);
   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
   switch (CastOpcode) {
   case ISD::SINT_TO_FP:
   case ISD::UINT_TO_FP:
     if (!TLI.isOperationLegalOrCustom(CastOpcode, ConcatSrcVT) ||
         !TLI.isTypeLegal(VT))
       return SDValue();

llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

if (PartEVT == ValueVT)
     return Val;
 
   if (PartEVT.isVector()) {
     // If the element type of the source/dest vectors are the same, but the
     // parts vector has more elements than the value vector, then we have a
     // vector widening case (e.g. <2 x float> -> <4 x float>).  Extract the
     // elements we want.
     if (PartEVT.getVectorElementType() == ValueVT.getVectorElementType()) {
-      assert((PartEVT.getVectorElementCount().Min >
-              ValueVT.getVectorElementCount().Min) &&
-             (PartEVT.getVectorElementCount().Scalable ==
-              ValueVT.getVectorElementCount().Scalable) &&
+      assert((PartEVT.getVectorElementCount().getKnownMinValue() >
+              ValueVT.getVectorElementCount().getKnownMinValue()) &&
+             (PartEVT.getVectorElementCount().isScalable() ==
+              ValueVT.getVectorElementCount().isScalable()) &&
              "Cannot narrow, it would be a lossy transformation");
       return DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, ValueVT, Val,
                          DAG.getVectorIdxConstant(0, DL));
     }
 
     // Vector/Vector bitcast.
     if (ValueVT.getSizeInBits() == PartEVT.getSizeInBits())
       return DAG.getNode(ISD::BITCAST, DL, ValueVT, Val);
void SelectionDAGBuilder::visitGetElementPtr(const User &I) {
   bool IsVectorGEP = I.getType()->isVectorTy();
   ElementCount VectorElementCount =
       IsVectorGEP ? cast<VectorType>(I.getType())->getElementCount()
                   : ElementCount::getFixed(0);
 
   if (IsVectorGEP && !N.getValueType().isVector()) {
     LLVMContext &Context = *DAG.getContext();
     EVT VT = EVT::getVectorVT(Context, N.getValueType(), VectorElementCount);
-    if (VectorElementCount.Scalable)
+    if (VectorElementCount.isScalable())
       N = DAG.getSplatVector(VT, dl, N);
     else
       N = DAG.getSplatBuildVector(VT, dl, N);
   }
 
   for (gep_type_iterator GTI = gep_type_begin(&I), E = gep_type_end(&I);
        GTI != E; ++GTI) {
     const Value *Idx = GTI.getOperand();
if (StructType *StTy = GTI.getStructTypeOrNull()) {
       }
 
       // N = N + Idx * ElementMul;
       SDValue IdxN = getValue(Idx);
 
       if (!IdxN.getValueType().isVector() && IsVectorGEP) {
         EVT VT = EVT::getVectorVT(*Context, IdxN.getValueType(),
                                   VectorElementCount);
-        if (VectorElementCount.Scalable)
+        if (VectorElementCount.isScalable())
           IdxN = DAG.getSplatVector(VT, dl, IdxN);
         else
           IdxN = DAG.getSplatBuildVector(VT, dl, IdxN);
       }
 
       // If the index is smaller or larger than intptr_t, truncate or extend
       // it.
       IdxN = DAG.getSExtOrTrunc(IdxN, dl, N.getValueType());

llvm/lib/CodeGen/TargetLoweringBase.cpp

static unsigned getVectorTypeBreakdownMVT(MVT VT, MVT &IntermediateVT,
   // Figure out the right, legal destination reg to copy into.
   ElementCount EC = VT.getVectorElementCount();
   MVT EltTy = VT.getVectorElementType();
 
   unsigned NumVectorRegs = 1;
 
   // Scalable vectors cannot be scalarized, so splitting or widening is
   // required.
-  if (VT.isScalableVector() && !isPowerOf2_32(EC.Min))
+  if (VT.isScalableVector() && !isPowerOf2_32(EC.getKnownMinValue()))
     llvm_unreachable(
         "Splitting or widening of non-power-of-2 MVTs is not implemented.");
 
   // FIXME: We don't support non-power-of-2-sized vectors for now.
   // Ideally we could break down into LHS/RHS like LegalizeDAG does.
-  if (!isPowerOf2_32(EC.Min)) {
+  if (!isPowerOf2_32(EC.getKnownMinValue())) {
     // Split EC to unit size (scalable property is preserved).
-    NumVectorRegs = EC.Min;
-    EC = EC / NumVectorRegs;
+    NumVectorRegs = EC.getKnownMinValue();
+    EC = ElementCount::getFixed(1);
   }
 
   // Divide the input until we get to a supported size. This will
   // always end up with an EC that represent a scalar or a scalable
   // scalar.
-  while (EC.Min > 1 && !TLI->isTypeLegal(MVT::getVectorVT(EltTy, EC))) {
-    EC.Min >>= 1;
+  while (EC.getKnownMinValue() > 1 &&
+         !TLI->isTypeLegal(MVT::getVectorVT(EltTy, EC))) {
+    EC /= 2;
     NumVectorRegs <<= 1;
   }
 
   NumIntermediates = NumVectorRegs;
 
   MVT NewVT = MVT::getVectorVT(EltTy, EC);
   if (!TLI->isTypeLegal(NewVT))
     NewVT = EltTy;
case TypePromoteInteger: {
         }
       }
       if (IsLegalWiderType)
         break;
       LLVM_FALLTHROUGH;
     }
 
     case TypeWidenVector:
-      if (isPowerOf2_32(EC.Min)) {
+      if (isPowerOf2_32(EC.getKnownMinValue())) {
         // Try to widen the vector.
         for (unsigned nVT = i + 1; nVT <= MVT::LAST_VECTOR_VALUETYPE; ++nVT) {
           MVT SVT = (MVT::SimpleValueType) nVT;
           if (SVT.getVectorElementType() == EltVT &&
               SVT.isScalableVector() == IsScalable &&
-              SVT.getVectorElementCount().Min > EC.Min && isTypeLegal(SVT)) {
+              SVT.getVectorElementCount().getKnownMinValue() >
+                  EC.getKnownMinValue() &&
+              isTypeLegal(SVT)) {
             TransformToType[i] = SVT;
             RegisterTypeForVT[i] = SVT;
             NumRegistersForVT[i] = 1;
             ValueTypeActions.setTypeAction(VT, TypeWidenVector);
             IsLegalWiderType = true;
             break;
           }
         }
case TypeScalarizeVector: {
       MVT NVT = VT.getPow2VectorType();
       if (NVT == VT) {
         // Type is already a power of 2.  The default action is to split.
         TransformToType[i] = MVT::Other;
         if (PreferredAction == TypeScalarizeVector)
           ValueTypeActions.setTypeAction(VT, TypeScalarizeVector);
         else if (PreferredAction == TypeSplitVector)
           ValueTypeActions.setTypeAction(VT, TypeSplitVector);
-        else if (EC.Min > 1)
+        else if (EC.getKnownMinValue() > 1)
           ValueTypeActions.setTypeAction(VT, TypeSplitVector);
         else
-          ValueTypeActions.setTypeAction(VT, EC.Scalable
+          ValueTypeActions.setTypeAction(VT, EC.isScalable()
                                                  ? TypeScalarizeScalableVector
                                                  : TypeScalarizeVector);
       } else {
         TransformToType[i] = NVT;
         ValueTypeActions.setTypeAction(VT, TypeWidenVector);
       }
       break;
     }
unsigned TargetLoweringBase::getVectorTypeBreakdown(LLVMContext &Context, EVT VT,
   ElementCount EltCnt = VT.getVectorElementCount();
 
   // If there is a wider vector type with the same element type as this one,
   // or a promoted vector type that has the same number of elements which
   // are wider, then we should convert to that legal vector type.
   // This handles things like <2 x float> -> <4 x float> and
   // <4 x i1> -> <4 x i32>.
   LegalizeTypeAction TA = getTypeAction(Context, VT);
-  if (EltCnt.Min != 1 && (TA == TypeWidenVector || TA == TypePromoteInteger)) {
+  if (EltCnt.getKnownMinValue() != 1 &&
+      (TA == TypeWidenVector || TA == TypePromoteInteger)) {
     EVT RegisterEVT = getTypeToTransformTo(Context, VT);
     if (isTypeLegal(RegisterEVT)) {
       IntermediateVT = RegisterEVT;
       RegisterVT = RegisterEVT.getSimpleVT();
       NumIntermediates = 1;
       return 1;
     }
   }
 
   // Figure out the right, legal destination reg to copy into.
   EVT EltTy = VT.getVectorElementType();
 
   unsigned NumVectorRegs = 1;
 
   // Scalable vectors cannot be scalarized, so handle the legalisation of the
   // types like done elsewhere in SelectionDAG.
-  if (VT.isScalableVector() && !isPowerOf2_32(EltCnt.Min)) {
+  if (VT.isScalableVector() && !isPowerOf2_32(EltCnt.getKnownMinValue())) {
     LegalizeKind LK;
     EVT PartVT = VT;
     do {
       // Iterate until we've found a legal (part) type to hold VT.
       LK = getTypeConversion(Context, PartVT);
       PartVT = LK.second;
     } while (LK.first != TypeLegal);
 
-    NumIntermediates =
-        VT.getVectorElementCount().Min / PartVT.getVectorElementCount().Min;
+    NumIntermediates = VT.getVectorElementCount().getKnownMinValue() /
+                       PartVT.getVectorElementCount().getKnownMinValue();
 
     // FIXME: This code needs to be extended to handle more complex vector
     // breakdowns, like nxv7i64 -> nxv8i64 -> 4 x nxv2i64. Currently the only
     // supported cases are vectors that are broken down into equal parts
     // such as nxv6i64 -> 3 x nxv2i64.
-    assert(NumIntermediates * PartVT.getVectorElementCount().Min ==
-               VT.getVectorElementCount().Min &&
+    assert((PartVT.getVectorElementCount() * NumIntermediates) ==
+               VT.getVectorElementCount() &&
            "Expected an integer multiple of PartVT");
     IntermediateVT = PartVT;
     RegisterVT = getRegisterType(Context, IntermediateVT);
     return NumIntermediates;
   }
 
   // FIXME: We don't support non-power-of-2-sized vectors for now.  Ideally
   // we could break down into LHS/RHS like LegalizeDAG does.
-  if (!isPowerOf2_32(EltCnt.Min)) {
-    NumVectorRegs = EltCnt.Min;
-    EltCnt.Min = 1;
+  if (!isPowerOf2_32(EltCnt.getKnownMinValue())) {
+    NumVectorRegs = EltCnt.getKnownMinValue();
+    EltCnt = ElementCount::getFixed(1);
   }
 
   // Divide the input until we get to a supported size.  This will always
   // end with a scalar if the target doesn't support vectors.
-  while (EltCnt.Min > 1 &&
+  while (EltCnt.getKnownMinValue() > 1 &&
          !isTypeLegal(EVT::getVectorVT(Context, EltTy, EltCnt))) {
-    EltCnt.Min >>= 1;
+    EltCnt /= 2;
     NumVectorRegs <<= 1;
   }
 
   NumIntermediates = NumVectorRegs;
 
   EVT NewVT = EVT::getVectorVT(Context, EltTy, EltCnt);
   if (!isTypeLegal(NewVT))
     NewVT = EltTy;

llvm/lib/CodeGen/ValueTypes.cpp

 EVT EVT::getExtendedVectorElementType() const {
   assert(isExtended() && "Type is not extended!");
   return EVT::getEVT(cast<VectorType>(LLVMTy)->getElementType());
 }
 
 unsigned EVT::getExtendedVectorNumElements() const {
   assert(isExtended() && "Type is not extended!");
   ElementCount EC = cast<VectorType>(LLVMTy)->getElementCount();
-  if (EC.Scalable) {
+  if (EC.isScalable()) {
     WithColor::warning()
         << "The code that requested the fixed number of elements has made the "
            "assumption that this vector is not scalable. This assumption was "
            "not correct, and this may lead to broken code\n";
   }
-  return EC.Min;
+  return EC.getKnownMinValue();
 }
 
 ElementCount EVT::getExtendedVectorElementCount() const {
   assert(isExtended() && "Type is not extended!");
   return cast<VectorType>(LLVMTy)->getElementCount();
 }
 
 TypeSize EVT::getExtendedSizeInBits() const {
   assert(isExtended() && "Type is not extended!");
   if (IntegerType *ITy = dyn_cast<IntegerType>(LLVMTy))
     return TypeSize::Fixed(ITy->getBitWidth());
   if (VectorType *VTy = dyn_cast<VectorType>(LLVMTy))
     return VTy->getPrimitiveSizeInBits();
   llvm_unreachable("Unrecognized extended type!");
 }
 
 /// getEVTString - This function returns value type as a string, e.g. "i32".
 std::string EVT::getEVTString() const {
   switch (V.SimpleTy) {
   default:
     if (isVector())
-      return (isScalableVector() ? "nxv" : "v")
-             + utostr(getVectorElementCount().Min)
-             + getVectorElementType().getEVTString();
+      return (isScalableVector() ? "nxv" : "v") +
+             utostr(getVectorElementCount().getKnownMinValue()) +
+             getVectorElementType().getEVTString();
     if (isInteger())
       return "i" + utostr(getSizeInBits());
     if (isFloatingPoint())
       return "f" + utostr(getSizeInBits());
     llvm_unreachable("Invalid EVT!");
   case MVT::bf16:    return "bf16";
   case MVT::ppcf128: return "ppcf128";
   case MVT::isVoid:  return "isVoid";

llvm/lib/IR/AsmWriter.cpp

case Type::ArrayTyID: {
     OS << ']';
     return;
   }
   case Type::FixedVectorTyID:
   case Type::ScalableVectorTyID: {
     VectorType *PTy = cast<VectorType>(Ty);
     ElementCount EC = PTy->getElementCount();
     OS << "<";
-    if (EC.Scalable)
+    if (EC.isScalable())
       OS << "vscale x ";
-    OS << EC.Min << " x ";
+    OS << EC.getKnownMinValue() << " x ";
     print(PTy->getElementType(), OS);
     OS << '>';
     return;
   }
   }
   llvm_unreachable("Invalid TypeID");
 }
 

llvm/lib/IR/ConstantFold.cpp

Constant *llvm::ConstantFoldShuffleVectorInstruction(Constant *V1, Constant *V2,
   // Undefined shuffle mask -> undefined value.
   if (all_of(Mask, [](int Elt) { return Elt == UndefMaskElem; })) {
     return UndefValue::get(FixedVectorType::get(EltTy, MaskNumElts));
   }
 
   // If the mask is all zeros this is a splat, no need to go through all
   // elements.
   if (all_of(Mask, [](int Elt) { return Elt == 0; }) &&
-      !MaskEltCount.Scalable) {
+      !MaskEltCount.isScalable()) {
     Type *Ty = IntegerType::get(V1->getContext(), 32);
     Constant *Elt =
         ConstantExpr::getExtractElement(V1, ConstantInt::get(Ty, 0));
     return ConstantVector::getSplat(MaskEltCount, Elt);
   }
   // Do not iterate on scalable vector. The num of elements is unknown at
   // compile-time.
   if (isa<ScalableVectorType>(V1VTy))
     return nullptr;
 
-  unsigned SrcNumElts = V1VTy->getElementCount().Min;
+  unsigned SrcNumElts = V1VTy->getElementCount().getKnownMinValue();
 
   // Loop over the shuffle mask, evaluating each element.
   SmallVector<Constant*, 32> Result;
   for (unsigned i = 0; i != MaskNumElts; ++i) {
     int Elt = Mask[i];
     if (Elt == -1) {
       Result.push_back(UndefValue::get(EltTy));
       continue;
if (Constant *C1Splat = C1->getSplatValue())
             C1VTy->getElementCount(),
             ConstantExpr::getCompare(pred, C1Splat, C2Splat));
 
     // If we can constant fold the comparison of each element, constant fold
     // the whole vector comparison.
     SmallVector<Constant*, 4> ResElts;
     Type *Ty = IntegerType::get(C1->getContext(), 32);
     // Compare the elements, producing an i1 result or constant expr.
-    for (unsigned i = 0, e = C1VTy->getElementCount().Min; i != e; ++i) {
+    for (unsigned I = 0, E = C1VTy->getElementCount().getKnownMinValue();
+         I != E; ++I) {
       Constant *C1E =
-        ConstantExpr::getExtractElement(C1, ConstantInt::get(Ty, i));
+          ConstantExpr::getExtractElement(C1, ConstantInt::get(Ty, I));
       Constant *C2E =
-        ConstantExpr::getExtractElement(C2, ConstantInt::get(Ty, i));
+          ConstantExpr::getExtractElement(C2, ConstantInt::get(Ty, I));
 
       ResElts.push_back(ConstantExpr::getCompare(pred, C1E, C2E));
     }
 
     return ConstantVector::get(ResElts);
   }
 
   if (C1->getType()->isFloatingPointTy() &&

llvm/lib/IR/Constants.cpp

if (ConstantDataSequential::isElementTypeCompatible(C->getType()))
     return getSequenceIfElementsMatch<ConstantDataVector>(C, V);
 
   // Otherwise, the element type isn't compatible with ConstantDataVector, or
   // the operand list contains a ConstantExpr or something else strange.
   return nullptr;
 }
 
 Constant *ConstantVector::getSplat(ElementCount EC, Constant *V) {
-  if (!EC.Scalable) {
+  if (!EC.isScalable()) {
     // If this splat is compatible with ConstantDataVector, use it instead of
     // ConstantVector.
     if ((isa<ConstantFP>(V) || isa<ConstantInt>(V)) &&
         ConstantDataSequential::isElementTypeCompatible(V->getType()))
-      return ConstantDataVector::getSplat(EC.Min, V);
+      return ConstantDataVector::getSplat(EC.getKnownMinValue(), V);
 
-    SmallVector<Constant *, 32> Elts(EC.Min, V);
+    SmallVector<Constant *, 32> Elts(EC.getKnownMinValue(), V);
     return get(Elts);
   }
 
   Type *VTy = VectorType::get(V->getType(), EC);
 
   if (V->isNullValue())
     return ConstantAggregateZero::get(VTy);
   else if (isa<UndefValue>(V))
     return UndefValue::get(VTy);
 
   Type *I32Ty = Type::getInt32Ty(VTy->getContext());
 
   // Move scalar into vector.
   Constant *UndefV = UndefValue::get(VTy);
   V = ConstantExpr::getInsertElement(UndefV, V, ConstantInt::get(I32Ty, 0));
   // Build shuffle mask to perform the splat.
-  SmallVector<int, 8> Zeros(EC.Min, 0);
+  SmallVector<int, 8> Zeros(EC.getKnownMinValue(), 0);
   // Splat.
   return ConstantExpr::getShuffleVector(V, UndefV, Zeros);
 }
 
 ConstantTokenNone *ConstantTokenNone::get(LLVMContext &Context) {
   LLVMContextImpl *pImpl = Context.pImpl;
   if (!pImpl->TheNoneToken)
     pImpl->TheNoneToken.reset(new ConstantTokenNone(Context));
Constant *ConstantExpr::getGetElementPtr(Type *Ty, Constant *C,
   auto EltCount = ElementCount::getFixed(0);
   if (VectorType *VecTy = dyn_cast<VectorType>(C->getType()))
     EltCount = VecTy->getElementCount();
   else
     for (auto Idx : Idxs)
       if (VectorType *VecTy = dyn_cast<VectorType>(Idx->getType()))
         EltCount = VecTy->getElementCount();
 
-  if (EltCount.Min != 0)
+  if (EltCount.isNonZero())
     ReqTy = VectorType::get(ReqTy, EltCount);
 
   if (OnlyIfReducedTy == ReqTy)
     return nullptr;
 
   // Look up the constant in the table first to ensure uniqueness
   std::vector<Constant*> ArgVec;
   ArgVec.reserve(1 + Idxs.size());
   ArgVec.push_back(C);
   auto GTI = gep_type_begin(Ty, Idxs), GTE = gep_type_end(Ty, Idxs);
   for (; GTI != GTE; ++GTI) {
     auto *Idx = cast<Constant>(GTI.getOperand());
     assert(
         (!isa<VectorType>(Idx->getType()) ||
          cast<VectorType>(Idx->getType())->getElementCount() == EltCount) &&
         "getelementptr index type missmatch");
 
     if (GTI.isStruct() && Idx->getType()->isVectorTy()) {
       Idx = Idx->getSplatValue();
-    } else if (GTI.isSequential() && EltCount.Min != 0 &&
+    } else if (GTI.isSequential() && EltCount.isNonZero() &&
                !Idx->getType()->isVectorTy()) {
       Idx = ConstantVector::getSplat(EltCount, Idx);
     }
     ArgVec.push_back(Idx);
   }
 
   unsigned SubClassOptionalData = InBounds ? GEPOperator::IsInBounds : 0;
   if (InRangeIndex && *InRangeIndex < 63)

llvm/lib/IR/Core.cpp

unsigned LLVMGetArrayLength(LLVMTypeRef ArrayTy) {
   return unwrap<ArrayType>(ArrayTy)->getNumElements();
 }
 
 unsigned LLVMGetPointerAddressSpace(LLVMTypeRef PointerTy) {
   return unwrap<PointerType>(PointerTy)->getAddressSpace();
 }
 
 unsigned LLVMGetVectorSize(LLVMTypeRef VectorTy) {
-  return unwrap<VectorType>(VectorTy)->getElementCount().Min;
+  return unwrap<VectorType>(VectorTy)->getElementCount().getKnownMinValue();
 }
 
 /*--.. Operations on other types ...........................................--*/
 
 LLVMTypeRef LLVMVoidTypeInContext(LLVMContextRef C)  {
   return wrap(Type::getVoidTy(*unwrap(C)));
 }
 LLVMTypeRef LLVMLabelTypeInContext(LLVMContextRef C) {

llvm/lib/IR/DataLayout.cpp

Align DataLayout::getAlignmentInfo(AlignTypeEnum AlignType, uint32_t BitWidth,
   } else if (AlignType == VECTOR_ALIGN) {
     // By default, use natural alignment for vector types. This is consistent
     // with what clang and llvm-gcc do.
     unsigned Alignment =
         getTypeAllocSize(cast<VectorType>(Ty)->getElementType());
     // We're only calculating a natural alignment, so it doesn't have to be
     // based on the full size for scalable vectors. Using the minimum element
     // count should be enough here.
-    Alignment *= cast<VectorType>(Ty)->getElementCount().Min;
+    Alignment *= cast<VectorType>(Ty)->getElementCount().getKnownMinValue();
     Alignment = PowerOf2Ceil(Alignment);
     return Align(Alignment);
    }
 
   // If we still couldn't find a reasonable default alignment, fall back
   // to a simple heuristic that the alignment is the first power of two
   // greater-or-equal to the store size of the type.  This is a reasonable
   // approximation of reality, and if the user wanted something less

llvm/lib/IR/Function.cpp

if (PointerType* PTyp = dyn_cast<PointerType>(Ty)) {
     for (size_t i = 0; i < FT->getNumParams(); i++)
       Result += getMangledTypeStr(FT->getParamType(i));
     if (FT->isVarArg())
       Result += "vararg";
     // Ensure nested function types are distinguishable.
     Result += "f";
   } else if (VectorType* VTy = dyn_cast<VectorType>(Ty)) {
     ElementCount EC = VTy->getElementCount();
-    if (EC.Scalable)
+    if (EC.isScalable())
       Result += "nx";
-    Result += "v" + utostr(EC.Min) + getMangledTypeStr(VTy->getElementType());
+    Result += "v" + utostr(EC.getKnownMinValue()) +
+              getMangledTypeStr(VTy->getElementType());
   } else if (Ty) {
     switch (Ty->getTypeID()) {
     default: llvm_unreachable("Unhandled type");
     case Type::VoidTyID:      Result += "isVoid";   break;
     case Type::MetadataTyID:  Result += "Metadata"; break;
     case Type::HalfTyID:      Result += "f16";      break;
     case Type::BFloatTyID:    Result += "bf16";     break;
     case Type::FloatTyID:     Result += "f32";      break;

llvm/lib/IR/IRBuilder.cpp

 Value *IRBuilderBase::CreateVectorSplat(unsigned NumElts, Value *V,
                                         const Twine &Name) {
   auto EC = ElementCount::getFixed(NumElts);
   return CreateVectorSplat(EC, V, Name);
 }
 
 Value *IRBuilderBase::CreateVectorSplat(ElementCount EC, Value *V,
                                         const Twine &Name) {
-  assert(EC.Min > 0 && "Cannot splat to an empty vector!");
+  assert(EC.isNonZero() && "Cannot splat to an empty vector!");
 
   // First insert it into an undef vector so we can shuffle it.
   Type *I32Ty = getInt32Ty();
   Value *Undef = UndefValue::get(VectorType::get(V->getType(), EC));
   V = CreateInsertElement(Undef, V, ConstantInt::get(I32Ty, 0),
                           Name + ".splatinsert");
 
   // Shuffle the value across the desired number of elements.

llvm/lib/IR/Instructions.cpp

 
 bool ShuffleVectorInst::isValidOperands(const Value *V1, const Value *V2,
                                         ArrayRef<int> Mask) {
   // V1 and V2 must be vectors of the same type.
   if (!isa<VectorType>(V1->getType()) || V1->getType() != V2->getType())
     return false;
 
   // Make sure the mask elements make sense.
-  int V1Size = cast<VectorType>(V1->getType())->getElementCount().Min;
+  int V1Size =
+      cast<VectorType>(V1->getType())->getElementCount().getKnownMinValue();
   for (int Elem : Mask)
     if (Elem != UndefMaskElem && Elem >= V1Size * 2)
       return false;
 
   if (isa<ScalableVectorType>(V1->getType()))
     if ((Mask[0] != 0 && Mask[0] != UndefMaskElem) || !is_splat(Mask))
       return false;
 
bool ShuffleVectorInst::isValidOperands(const Value *V1, const Value *V2,
   return false;
 }
 
 void ShuffleVectorInst::getShuffleMask(const Constant *Mask,
                                        SmallVectorImpl<int> &Result) {
   ElementCount EC = cast<VectorType>(Mask->getType())->getElementCount();
 
   if (isa<ConstantAggregateZero>(Mask)) {
-    Result.resize(EC.Min, 0);
+    Result.resize(EC.getKnownMinValue(), 0);
     return;
   }
 
-  Result.reserve(EC.Min);
+  Result.reserve(EC.getKnownMinValue());
 
-  if (EC.Scalable) {
+  if (EC.isScalable()) {
     assert((isa<ConstantAggregateZero>(Mask) || isa<UndefValue>(Mask)) &&
            "Scalable vector shuffle mask must be undef or zeroinitializer");
     int MaskVal = isa<UndefValue>(Mask) ? -1 : 0;
-    for (unsigned I = 0; I < EC.Min; ++I)
+    for (unsigned I = 0; I < EC.getKnownMinValue(); ++I)
       Result.emplace_back(MaskVal);
     return;
   }
 
-  unsigned NumElts = EC.Min;
+  unsigned NumElts = EC.getKnownMinValue();
 
   if (auto *CDS = dyn_cast<ConstantDataSequential>(Mask)) {
     for (unsigned i = 0; i != NumElts; ++i)
       Result.push_back(CDS->getElementAsInteger(i));
     return;
   }
   for (unsigned i = 0; i != NumElts; ++i) {
     Constant *C = Mask->getAggregateElement(i);

llvm/lib/IR/IntrinsicInst.cpp

bool VPIntrinsic::canIgnoreVectorLengthParam() const {
   if (!VLParam)
     return true;
 
   // Note that the VP intrinsic causes undefined behavior if the Explicit Vector
   // Length parameter is strictly greater-than the number of vector elements of
   // the operation. This function returns true when this is detected statically
   // in the IR.
 
-  // Check whether "W == vscale * EC.Min"
-  if (EC.Scalable) {
+  // Check whether "W == vscale * EC.getKnownMinValue()"
+  if (EC.isScalable()) {
     // Undig the DL
     auto ParMod = this->getModule();
     if (!ParMod)
       return false;
     const auto &DL = ParMod->getDataLayout();
 
     // Compare vscale patterns
     uint64_t VScaleFactor;
     if (match(VLParam, m_c_Mul(m_ConstantInt(VScaleFactor), m_VScale(DL))))
-      return VScaleFactor >= EC.Min;
-    return (EC.Min == 1) && match(VLParam, m_VScale(DL));
+      return VScaleFactor >= EC.getKnownMinValue();
+    return (EC.getKnownMinValue() == 1) && match(VLParam, m_VScale(DL));
   }
 
   // standard SIMD operation
   auto VLConst = dyn_cast<ConstantInt>(VLParam);
   if (!VLConst)
     return false;
 
   uint64_t VLNum = VLConst->getZExtValue();
-  if (VLNum >= EC.Min)
+  if (VLNum >= EC.getKnownMinValue())
     return true;
 
   return false;
 }
 
 Instruction::BinaryOps BinaryOpIntrinsic::getBinaryOp() const {
   switch (getIntrinsicID()) {
   case Intrinsic::uadd_with_overflow:

llvm/lib/IR/Type.cpp

TypeSize Type::getPrimitiveSizeInBits() const {
   case Type::IntegerTyID:
     return TypeSize::Fixed(cast<IntegerType>(this)->getBitWidth());
   case Type::FixedVectorTyID:
   case Type::ScalableVectorTyID: {
     const VectorType *VTy = cast<VectorType>(this);
     ElementCount EC = VTy->getElementCount();
     TypeSize ETS = VTy->getElementType()->getPrimitiveSizeInBits();
     assert(!ETS.isScalable() && "Vector type should have fixed-width elements");
-    return {ETS.getFixedSize() * EC.Min, EC.Scalable};
+    return {ETS.getFixedSize() * EC.getKnownMinValue(), EC.isScalable()};
   }
   default: return TypeSize::Fixed(0);
   }
 }
 
 unsigned Type::getScalarSizeInBits() const {
   // It is safe to assume that the scalar types have a fixed size.
   return getScalarType()->getPrimitiveSizeInBits().getFixedSize();

 VectorType::VectorType(Type *ElType, unsigned EQ, Type::TypeID TID)
     : Type(ElType->getContext(), TID), ContainedType(ElType),
       ElementQuantity(EQ) {
   ContainedTys = &ContainedType;
   NumContainedTys = 1;
 }
 
 VectorType *VectorType::get(Type *ElementType, ElementCount EC) {
-  if (EC.Scalable)
-    return ScalableVectorType::get(ElementType, EC.Min);
+  if (EC.isScalable())
+    return ScalableVectorType::get(ElementType, EC.getKnownMinValue());
   else
-    return FixedVectorType::get(ElementType, EC.Min);
+    return FixedVectorType::get(ElementType, EC.getKnownMinValue());
 }
 
 bool VectorType::isValidElementType(Type *ElemTy) {
   return ElemTy->isIntegerTy() || ElemTy->isFloatingPointTy() ||
          ElemTy->isPointerTy();
 }
 
 //===----------------------------------------------------------------------===//

llvm/lib/Target/AArch64/AArch64ISelDAGToDAG.cpp

static EVT getPackedVectorTypeFromPredicateType(LLVMContext &Ctx, EVT PredVT,
   if (!PredVT.isScalableVector() || PredVT.getVectorElementType() != MVT::i1)
     return EVT();
 
   if (PredVT != MVT::nxv16i1 && PredVT != MVT::nxv8i1 &&
       PredVT != MVT::nxv4i1 && PredVT != MVT::nxv2i1)
     return EVT();
 
   ElementCount EC = PredVT.getVectorElementCount();
-  EVT ScalarVT = EVT::getIntegerVT(Ctx, AArch64::SVEBitsPerBlock / EC.Min);
+  EVT ScalarVT =
+      EVT::getIntegerVT(Ctx, AArch64::SVEBitsPerBlock / EC.getKnownMinValue());
   EVT MemVT = EVT::getVectorVT(Ctx, ScalarVT, EC * NumVec);
 
   return MemVT;
 }
 
 /// Return the EVT of the data associated to a memory operation in \p
 /// Root. If such EVT cannot be retrived, it returns an invalid EVT.
 static EVT getMemVTFromNode(LLVMContext &Ctx, SDNode *Root) {

llvm/lib/Target/AArch64/AArch64ISelLowering.cpp

if (VT.isVector()) {
     }
 
     if (StoreNode->isTruncatingStore()) {
       return LowerTruncateVectorStore(Dl, StoreNode, VT, MemVT, DAG);
     }
     // 256 bit non-temporal stores can be lowered to STNP. Do this as part of
     // the custom lowering, as there are no un-paired non-temporal stores and
     // legalization will break up 256 bit inputs.
+    ElementCount EC = MemVT.getVectorElementCount();
     if (StoreNode->isNonTemporal() && MemVT.getSizeInBits() == 256u &&
-        MemVT.getVectorElementCount().Min % 2u == 0 &&
+        EC.isKnownEven() &&
         ((MemVT.getScalarSizeInBits() == 8u ||
           MemVT.getScalarSizeInBits() == 16u ||
           MemVT.getScalarSizeInBits() == 32u ||
           MemVT.getScalarSizeInBits() == 64u))) {
       SDValue Lo =
           DAG.getNode(ISD::EXTRACT_SUBVECTOR, Dl,
                       MemVT.getHalfNumVectorElementsVT(*DAG.getContext()),
                       StoreNode->getValue(), DAG.getConstant(0, Dl, MVT::i64));
-      SDValue Hi = DAG.getNode(
-          ISD::EXTRACT_SUBVECTOR, Dl,
+      SDValue Hi =
+          DAG.getNode(ISD::EXTRACT_SUBVECTOR, Dl,
                       MemVT.getHalfNumVectorElementsVT(*DAG.getContext()),
                       StoreNode->getValue(),
-          DAG.getConstant(MemVT.getVectorElementCount().Min / 2, Dl, MVT::i64));
+                      DAG.getConstant(EC.getKnownMinValue() / 2, Dl, MVT::i64));
       SDValue Result = DAG.getMemIntrinsicNode(
           AArch64ISD::STNP, Dl, DAG.getVTList(MVT::Other),
           {StoreNode->getChain(), Lo, Hi, StoreNode->getBasePtr()},
           StoreNode->getMemoryVT(), StoreNode->getMemOperand());
       return Result;
     }
   } else if (MemVT == MVT::i128 && StoreNode->isVolatile()) {
     assert(StoreNode->getValue()->getValueType(0) == MVT::i128);
SDValue AArch64TargetLowering::LowerSVEStructLoad(unsigned Intrinsic,
 
   unsigned N, Opcode;
   static std::map<unsigned, std::pair<unsigned, unsigned>> IntrinsicMap = {
       {Intrinsic::aarch64_sve_ld2, {2, AArch64ISD::SVE_LD2_MERGE_ZERO}},
       {Intrinsic::aarch64_sve_ld3, {3, AArch64ISD::SVE_LD3_MERGE_ZERO}},
       {Intrinsic::aarch64_sve_ld4, {4, AArch64ISD::SVE_LD4_MERGE_ZERO}}};
 
   std::tie(N, Opcode) = IntrinsicMap[Intrinsic];
-  assert(VT.getVectorElementCount().Min % N == 0 &&
+  assert(VT.getVectorElementCount().getKnownMinValue() % N == 0 &&
          "invalid tuple vector type!");
 
   EVT SplitVT = EVT::getVectorVT(*DAG.getContext(), VT.getVectorElementType(),
                                  VT.getVectorElementCount() / N);
   assert(isTypeLegal(SplitVT));
 
   SmallVector<EVT, 5> VTs(N, SplitVT);
   VTs.push_back(MVT::Other); // Chain
case ISD::INTRINSIC_W_CHAIN:
     case Intrinsic::aarch64_sve_tuple_get: {
       SDLoc DL(N);
       SDValue Chain = N->getOperand(0);
       SDValue Src1 = N->getOperand(2);
       SDValue Idx = N->getOperand(3);
 
       uint64_t IdxConst = cast<ConstantSDNode>(Idx)->getZExtValue();
       EVT ResVT = N->getValueType(0);
-      uint64_t NumLanes = ResVT.getVectorElementCount().Min;
+      uint64_t NumLanes = ResVT.getVectorElementCount().getKnownMinValue();
       SDValue ExtIdx = DAG.getVectorIdxConstant(IdxConst * NumLanes, DL);
       SDValue Val =
           DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, ResVT, Src1, ExtIdx);
       return DAG.getMergeValues({Val, Chain}, DL);
     }
     case Intrinsic::aarch64_sve_tuple_set: {
       SDLoc DL(N);
       SDValue Chain = N->getOperand(0);
       SDValue Tuple = N->getOperand(2);
       SDValue Idx = N->getOperand(3);
       SDValue Vec = N->getOperand(4);
 
       EVT TupleVT = Tuple.getValueType();
-      uint64_t TupleLanes = TupleVT.getVectorElementCount().Min;
+      uint64_t TupleLanes = TupleVT.getVectorElementCount().getKnownMinValue();
 
       uint64_t IdxConst = cast<ConstantSDNode>(Idx)->getZExtValue();
-      uint64_t NumLanes = Vec.getValueType().getVectorElementCount().Min;
+      uint64_t NumLanes =
+          Vec.getValueType().getVectorElementCount().getKnownMinValue();
 
       if ((TupleLanes % NumLanes) != 0)
         report_fatal_error("invalid tuple vector!");
 
       uint64_t NumVecs = TupleLanes / NumLanes;
 
       SmallVector<SDValue, 4> Opnds;
       for (unsigned I = 0; I < NumVecs; ++I) {
void AArch64TargetLowering::ReplaceExtractSubVectorResults(
 
   SDLoc DL(N);
   EVT VT = N->getValueType(0);
 
   // The following checks bail if this is not a halving operation.
 
   ElementCount ResEC = VT.getVectorElementCount();
 
-  if (InVT.getVectorElementCount().Min != (ResEC.Min * 2))
+  if (InVT.getVectorElementCount() != (ResEC * 2))
     return;
 
   auto *CIndex = dyn_cast<ConstantSDNode>(N->getOperand(1));
   if (!CIndex)
     return;
 
   unsigned Index = CIndex->getZExtValue();
-  if ((Index != 0) && (Index != ResEC.Min))
+  if ((Index != 0) && (Index != ResEC.getKnownMinValue()))
     return;
 
   unsigned Opcode = (Index == 0) ? AArch64ISD::UUNPKLO : AArch64ISD::UUNPKHI;
   EVT ExtendedHalfVT = VT.widenIntegerVectorElementType(*DAG.getContext());
 
   SDValue Half = DAG.getNode(Opcode, DL, ExtendedHalfVT, N->getOperand(0));
   Results.push_back(DAG.getNode(ISD::TRUNCATE, DL, VT, Half));
 }

llvm/lib/Transforms/InstCombine/InstCombineVectorOps.cpp

if (Value *V = SimplifyExtractElementInst(SrcVec, Index,
                                             SQ.getWithInstruction(&EI)))
     return replaceInstUsesWith(EI, V);
 
   // If extracting a specified index from the vector, see if we can recursively
   // find a previously computed scalar that was inserted into the vector.
   auto *IndexC = dyn_cast<ConstantInt>(Index);
   if (IndexC) {
     ElementCount EC = EI.getVectorOperandType()->getElementCount();
-    unsigned NumElts = EC.Min;
+    unsigned NumElts = EC.getKnownMinValue();
 
     // InstSimplify should handle cases where the index is invalid.
     // For fixed-length vector, it's invalid to extract out-of-range element.
-    if (!EC.Scalable && IndexC->getValue().uge(NumElts))
+    if (!EC.isScalable() && IndexC->getValue().uge(NumElts))
       return nullptr;
 
     // This instruction only demands the single element from the input vector.
     // Skip for scalable type, the number of elements is unknown at
     // compile-time.
-    if (!EC.Scalable && NumElts != 1) {
+    if (!EC.isScalable() && NumElts != 1) {
       // If the input vector has a single use, simplify it based on this use
       // property.
       if (SrcVec->hasOneUse()) {
         APInt UndefElts(NumElts, 0);
         APInt DemandedElts(NumElts, 0);
         DemandedElts.setBit(IndexC->getZExtValue());
         if (Value *V =
                 SimplifyDemandedVectorElts(SrcVec, DemandedElts, UndefElts))

llvm/lib/Transforms/Utils/FunctionComparator.cpp

case Type::ArrayTyID: {
     if (STyL->getNumElements() != STyR->getNumElements())
       return cmpNumbers(STyL->getNumElements(), STyR->getNumElements());
     return cmpTypes(STyL->getElementType(), STyR->getElementType());
   }
   case Type::FixedVectorTyID:
   case Type::ScalableVectorTyID: {
     auto *STyL = cast<VectorType>(TyL);
     auto *STyR = cast<VectorType>(TyR);
-    if (STyL->getElementCount().Scalable != STyR->getElementCount().Scalable)
-      return cmpNumbers(STyL->getElementCount().Scalable,
-                        STyR->getElementCount().Scalable);
-    if (STyL->getElementCount().Min != STyR->getElementCount().Min)
-      return cmpNumbers(STyL->getElementCount().Min,
-                        STyR->getElementCount().Min);
+    if (STyL->getElementCount().isScalable() !=
+        STyR->getElementCount().isScalable())
+      return cmpNumbers(STyL->getElementCount().isScalable(),
+                        STyR->getElementCount().isScalable());
+    if (STyL->getElementCount() != STyR->getElementCount())
+      return cmpNumbers(STyL->getElementCount().getKnownMinValue(),
+                        STyR->getElementCount().getKnownMinValue());
     return cmpTypes(STyL->getElementType(), STyR->getElementType());
   }
   }
 }
 
 // Determine whether the two operations are the same except that pointer-to-A
 // and pointer-to-B are equivalent. This should be kept in sync with
 // Instruction::isSameOperationAs.

llvm/lib/Transforms/Vectorize/LoopVectorize.cpp

if (auto *LI = dyn_cast<LoadInst>(I))
     return LI->getType();
   return cast<StoreInst>(I)->getValueOperand()->getType();
 }
 
 /// A helper function that returns true if the given type is irregular. The
 /// type is irregular if its allocated size doesn't equal the store size of an
 /// element of the corresponding vector type at the given vectorization factor.
 static bool hasIrregularType(Type *Ty, const DataLayout &DL, ElementCount VF) {
-  assert(!VF.Scalable && "scalable vectors not yet supported.");
+  assert(!VF.isScalable() && "scalable vectors not yet supported.");
   // Determine if an array of VF elements of type Ty is "bitcast compatible"
   // with a <VF x Ty> vector.
   if (VF.isVector()) {
     auto *VectorTy = VectorType::get(Ty, VF);
     return VF * DL.getTypeAllocSize(Ty) != DL.getTypeStoreSize(VectorTy);
   }
 
   // If the vectorization factor is one, we just check if an array of type Ty
static Instruction *getDebugLocFromInstOrOperands(Instruction *I) {
   return I;
 }
 
 void InnerLoopVectorizer::setDebugLocFromInst(IRBuilder<> &B, const Value *Ptr) {
   if (const Instruction *Inst = dyn_cast_or_null<Instruction>(Ptr)) {
     const DILocation *DIL = Inst->getDebugLoc();
     if (DIL && Inst->getFunction()->isDebugInfoForProfiling() &&
         !isa<DbgInfoIntrinsic>(Inst)) {
-      assert(!VF.Scalable && "scalable vectors not yet supported.");
-      auto NewDIL = DIL->cloneByMultiplyingDuplicationFactor(UF * VF.Min);
+      assert(!VF.isScalable() && "scalable vectors not yet supported.");
+      auto NewDIL =
+          DIL->cloneByMultiplyingDuplicationFactor(UF * VF.getKnownMinValue());
       if (NewDIL)
         B.SetCurrentDebugLocation(NewDIL.getValue());
       else
         LLVM_DEBUG(dbgs()
                    << "Failed to create new discriminator: "
                    << DIL->getFilename() << " Line: " << DIL->getLine());
     }
     else
for (unsigned i = 0; i < Grp->getFactor(); ++i) {
       }
     }
   }
 
   /// Return the cost model decision for the given instruction \p I and vector
   /// width \p VF. Return CM_Unknown if this instruction did not pass
   /// through the cost modeling.
   InstWidening getWideningDecision(Instruction *I, ElementCount VF) {
-    assert(!VF.Scalable && "scalable vectors not yet supported.");
+    assert(!VF.isScalable() && "scalable vectors not yet supported.");
     assert(VF.isVector() && "Expected VF >=2");
 
     // Cost model is not run in the VPlan-native path - return conservative
     // result until this changes.
     if (EnableVPlanNativePath)
       return CM_GatherScatter;
 
     std::pair<Instruction *, ElementCount> InstOnVF = std::make_pair(I, VF);
if (Step->getType()->isIntegerTy()) {
     MulOp = Instruction::Mul;
   } else {
     AddOp = II.getInductionOpcode();
     MulOp = Instruction::FMul;
   }
 
   // Multiply the vectorization factor by the step using integer or
   // floating-point arithmetic as appropriate.
-  Value *ConstVF = getSignedIntOrFpConstant(Step->getType(), VF.Min);
+  Value *ConstVF =
+      getSignedIntOrFpConstant(Step->getType(), VF.getKnownMinValue());
   Value *Mul = addFastMathFlag(Builder.CreateBinOp(MulOp, Step, ConstVF));
 
   // Create a vector splat to use in the induction update.
   //
   // FIXME: If the step is non-constant, we create the vector splat with
   //        IRBuilder. IRBuilder can constant-fold the multiply, but it doesn't
   //        handle a constant vector splat.
-  assert(!VF.Scalable && "scalable vectors not yet supported.");
+  assert(!VF.isScalable() && "scalable vectors not yet supported.");
   Value *SplatVF = isa<Constant>(Mul)
                        ? ConstantVector::getSplat(VF, cast<Constant>(Mul))
                        : Builder.CreateVectorSplat(VF, Mul);
   Builder.restoreIP(CurrIP);
 
   // We may need to add the step a number of times, depending on the unroll
   // factor. The last of those goes into the PHI.
   PHINode *VecInd = PHINode::Create(SteppedStart->getType(), 2, "vec.ind",
auto CreateScalarIV = [&](Value *&Step) -> Value * {
     return ScalarIV;
   };
 
   // Create the vector values from the scalar IV, in the absence of creating a
   // vector IV.
   auto CreateSplatIV = [&](Value *ScalarIV, Value *Step) {
     Value *Broadcasted = getBroadcastInstrs(ScalarIV);
     for (unsigned Part = 0; Part < UF; ++Part) {
-      assert(!VF.Scalable && "scalable vectors not yet supported.");
-      Value *EntryPart = getStepVector(Broadcasted, VF.Min * Part, Step,
-                                       ID.getInductionOpcode());
+      assert(!VF.isScalable() && "scalable vectors not yet supported.");
+      Value *EntryPart =
+          getStepVector(Broadcasted, VF.getKnownMinValue() * Part, Step,
       VectorLoopValueMap.setVectorValue(EntryVal, Part, EntryPart);
       if (Trunc)
         addMetadata(EntryPart, Trunc);
       recordVectorLoopValueForInductionCast(ID, EntryVal, EntryPart, Part);
     }
   };
 
   // Now do the actual transformations, and start with creating the step value.
Value *InnerLoopVectorizer::getStepVector(Value *Val, int StartIdx, Value *Step,
   return BOp;
 }
 
 void InnerLoopVectorizer::buildScalarSteps(Value *ScalarIV, Value *Step,
                                            Instruction *EntryVal,
                                            const InductionDescriptor &ID) {
   // We shouldn't have to build scalar steps if we aren't vectorizing.
   assert(VF.isVector() && "VF should be greater than one");
-  assert(!VF.Scalable &&
+  assert(!VF.isScalable() &&
          "the code below assumes a fixed number of elements at compile time");
   // Get the value type and ensure it and the step have the same integer type.
   Type *ScalarIVTy = ScalarIV->getType()->getScalarType();
   assert(ScalarIVTy == Step->getType() &&
          "Val and Step should have the same type");
 
   // We build scalar steps for both integer and floating-point induction
   // variables. Here, we determine the kind of arithmetic we will perform.
   Instruction::BinaryOps AddOp;
   Instruction::BinaryOps MulOp;
   if (ScalarIVTy->isIntegerTy()) {
     AddOp = Instruction::Add;
     MulOp = Instruction::Mul;
   } else {
     AddOp = ID.getInductionOpcode();