[TTI] Return a TypeSize from getRegisterBitWidth.

[sdesmalen]

Summary

This patch changes the interface to take a RegisterKind, to indicate
whether the register bitwidth of a scalar register, fixed-width vector
register, or scalable vector register must be returned.

[paulwalker-arm]

llvm/lib/Target/AArch64/AArch64TargetTransformInfo.h

111

I don't think you intended this change. getMinSVEVectorSizeInBits is used to enable larger fixed length vectors and so belongs with the request for RGK_FixedWidthVector.

[sdesmalen]

Moved code using getMinSVEVectorSizeInBits to RGK_FixedWidthVector.

[paulwalker-arm]

llvm/lib/Target/ARM/ARMTargetTransformInfo.h

157–158

Happy as is but do think the following looks nicer:

if (ST->hasNEON())
  return TypeSize::getFixed(128);
if (ST->hasMVEIntegerOps())
  return TypeSize::getFixed(128);
return TypeSize::getFixed(0);

[gulfem]

I think this commit caused an issue in one of the files in polly.
Please see the error message below:

[3469/3899] Building CXX object tools/polly/lib/CMakeFiles/obj.Polly.dir/Transform/ScheduleOptimizer.cpp.o
FAILED: tools/polly/lib/CMakeFiles/obj.Polly.dir/Transform/ScheduleOptimizer.cpp.o 
/b/s/w/ir/cache/goma/client/gomacc /b/s/w/ir/x/w/cipd/bin/clang++ --sysroot=/b/s/w/ir/x/w/cipd/linux -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools/polly/lib -I/b/s/w/ir/x/w/llvm-project/polly/lib -Itools/polly/include -I/b/s/w/ir/x/w/llvm-project/polly/lib/External -I/b/s/w/ir/x/w/llvm-project/polly/lib/External/pet/include -I/b/s/w/ir/x/w/llvm-project/polly/lib/External/isl/include -Itools/polly/lib/External/isl/include -I/b/s/w/ir/x/w/llvm-project/polly/include -Iinclude -I/b/s/w/ir/x/w/llvm-project/llvm/include -fPIC -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -fdiagnostics-color -ffunction-sections -fdata-sections -ffile-prefix-map=/b/s/w/ir/x/w/staging/llvm_build=../staging/llvm_build -ffile-prefix-map=/b/s/w/ir/x/w/llvm-project/= -no-canonical-prefixes -fno-exceptions -fno-rtti -O3   -fno-exceptions -fno-unwind-tables -fno-asynchronous-unwind-tables -fno-rtti -UNDEBUG -std=c++14 -MD -MT tools/polly/lib/CMakeFiles/obj.Polly.dir/Transform/ScheduleOptimizer.cpp.o -MF tools/polly/lib/CMakeFiles/obj.Polly.dir/Transform/ScheduleOptimizer.cpp.o.d -o tools/polly/lib/CMakeFiles/obj.Polly.dir/Transform/ScheduleOptimizer.cpp.o -c /b/s/w/ir/x/w/llvm-project/polly/lib/Transform/ScheduleOptimizer.cpp
/b/s/w/ir/x/w/llvm-project/polly/lib/Transform/ScheduleOptimizer.cpp:1220:49: error: cannot initialize a parameter of type 'llvm::TargetTransformInfo::RegisterKind' with an rvalue of type 'bool'
    RegisterBitwidth = TTI->getRegisterBitWidth(true);
                                                ^~~~
/b/s/w/ir/x/w/llvm-project/llvm/include/llvm/Analysis/TargetTransformInfo.h:926:45: note: passing argument to parameter 'K' here
  TypeSize getRegisterBitWidth(RegisterKind K) const;

[sdesmalen]

In D98874#2648095, @gulfem wrote:

I think this commit caused an issue in one of the files in polly.
Please see the error message below:

[3469/3899] Building CXX object tools/polly/lib/CMakeFiles/obj.Polly.dir/Transform/ScheduleOptimizer.cpp.o
FAILED: tools/polly/lib/CMakeFiles/obj.Polly.dir/Transform/ScheduleOptimizer.cpp.o 
/b/s/w/ir/cache/goma/client/gomacc /b/s/w/ir/x/w/cipd/bin/clang++ --sysroot=/b/s/w/ir/x/w/cipd/linux -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools/polly/lib -I/b/s/w/ir/x/w/llvm-project/polly/lib -Itools/polly/include -I/b/s/w/ir/x/w/llvm-project/polly/lib/External -I/b/s/w/ir/x/w/llvm-project/polly/lib/External/pet/include -I/b/s/w/ir/x/w/llvm-project/polly/lib/External/isl/include -Itools/polly/lib/External/isl/include -I/b/s/w/ir/x/w/llvm-project/polly/include -Iinclude -I/b/s/w/ir/x/w/llvm-project/llvm/include -fPIC -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -fdiagnostics-color -ffunction-sections -fdata-sections -ffile-prefix-map=/b/s/w/ir/x/w/staging/llvm_build=../staging/llvm_build -ffile-prefix-map=/b/s/w/ir/x/w/llvm-project/= -no-canonical-prefixes -fno-exceptions -fno-rtti -O3   -fno-exceptions -fno-unwind-tables -fno-asynchronous-unwind-tables -fno-rtti -UNDEBUG -std=c++14 -MD -MT tools/polly/lib/CMakeFiles/obj.Polly.dir/Transform/ScheduleOptimizer.cpp.o -MF tools/polly/lib/CMakeFiles/obj.Polly.dir/Transform/ScheduleOptimizer.cpp.o.d -o tools/polly/lib/CMakeFiles/obj.Polly.dir/Transform/ScheduleOptimizer.cpp.o -c /b/s/w/ir/x/w/llvm-project/polly/lib/Transform/ScheduleOptimizer.cpp
/b/s/w/ir/x/w/llvm-project/polly/lib/Transform/ScheduleOptimizer.cpp:1220:49: error: cannot initialize a parameter of type 'llvm::TargetTransformInfo::RegisterKind' with an rvalue of type 'bool'
    RegisterBitwidth = TTI->getRegisterBitWidth(true);
                                                ^~~~
/b/s/w/ir/x/w/llvm-project/llvm/include/llvm/Analysis/TargetTransformInfo.h:926:45: note: passing argument to parameter 'K' here
  TypeSize getRegisterBitWidth(RegisterKind K) const;

Thanks for pointing that out, I must have missed that one! I'll push a fix for it.

[sdesmalen]

Seems it was already fixed by rG7d91d81c6b6a456ca2362b691485c8e1b42809dd

llvm/include/llvm/Analysis/TargetTransformInfo.h

public:
   /// don't necessarily map onto the register classes used by the backend.
   /// FIXME: It's not currently possible to determine how many registers
   /// are used by the provided type.
   unsigned getRegisterClassForType(bool Vector, Type *Ty = nullptr) const;
 
   /// \return the target-provided register class name
   const char *getRegisterClassName(unsigned ClassID) const;
 
+  enum RegisterKind { RGK_Scalar, RGK_FixedWidthVector, RGK_ScalableVector };
+
   /// \return The width of the largest scalar or vector register type.
-  unsigned getRegisterBitWidth(bool Vector) const;
+  TypeSize getRegisterBitWidth(RegisterKind K) const;
 
   /// \return The width of the smallest vector register type.
   unsigned getMinVectorRegisterBitWidth() const;
 
   /// \return The maximum value of vscale if the target specifies an
   ///  architectural maximum vector length, and None otherwise.
   Optional<unsigned> getMaxVScale() const;
 
virtual int getIntImmCostInst(unsigned Opc, unsigned Idx, const APInt &Imm,
                                 Instruction *Inst = nullptr) = 0;
   virtual int getIntImmCostIntrin(Intrinsic::ID IID, unsigned Idx,
                                   const APInt &Imm, Type *Ty,
                                   TargetCostKind CostKind) = 0;
   virtual unsigned getNumberOfRegisters(unsigned ClassID) const = 0;
   virtual unsigned getRegisterClassForType(bool Vector,
                                            Type *Ty = nullptr) const = 0;
   virtual const char *getRegisterClassName(unsigned ClassID) const = 0;
-  virtual unsigned getRegisterBitWidth(bool Vector) const = 0;
+  virtual TypeSize getRegisterBitWidth(RegisterKind K) const = 0;
   virtual unsigned getMinVectorRegisterBitWidth() = 0;
   virtual Optional<unsigned> getMaxVScale() const = 0;
   virtual bool shouldMaximizeVectorBandwidth(bool OptSize) const = 0;
   virtual ElementCount getMinimumVF(unsigned ElemWidth,
                                     bool IsScalable) const = 0;
   virtual unsigned getMaximumVF(unsigned ElemWidth, unsigned Opcode) const = 0;
   virtual bool shouldConsiderAddressTypePromotion(
       const Instruction &I, bool &AllowPromotionWithoutCommonHeader) = 0;
public:
   }
   unsigned getRegisterClassForType(bool Vector,
                                    Type *Ty = nullptr) const override {
     return Impl.getRegisterClassForType(Vector, Ty);
   }
   const char *getRegisterClassName(unsigned ClassID) const override {
     return Impl.getRegisterClassName(ClassID);
   }
-  unsigned getRegisterBitWidth(bool Vector) const override {
-    return Impl.getRegisterBitWidth(Vector);
+  TypeSize getRegisterBitWidth(RegisterKind K) const override {
+    return Impl.getRegisterBitWidth(K);
   }
   unsigned getMinVectorRegisterBitWidth() override {
     return Impl.getMinVectorRegisterBitWidth();
   }
   Optional<unsigned> getMaxVScale() const override {
     return Impl.getMaxVScale();
   }
   bool shouldMaximizeVectorBandwidth(bool OptSize) const override {

llvm/include/llvm/Analysis/TargetTransformInfoImpl.h

default:
       return "Generic::Unknown Register Class";
     case 0:
       return "Generic::ScalarRC";
     case 1:
       return "Generic::VectorRC";
     }
   }
 
-  unsigned getRegisterBitWidth(bool Vector) const { return 32; }
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+    return TypeSize::getFixed(32);
+  }
 
   unsigned getMinVectorRegisterBitWidth() const { return 128; }
 
   Optional<unsigned> getMaxVScale() const { return None; }
 
   bool shouldMaximizeVectorBandwidth(bool OptSize) const { return false; }
 
   ElementCount getMinimumVF(unsigned ElemWidth, bool IsScalable) const {

llvm/include/llvm/CodeGen/BasicTTIImpl.h

virtual bool enableWritePrefetching() const {
     return getST()->enableWritePrefetching();
   }
 
   /// @}
 
   /// \name Vector TTI Implementations
   /// @{
 
-  unsigned getRegisterBitWidth(bool Vector) const { return 32; }
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+    return TypeSize::getFixed(32);
+  }
 
   Optional<unsigned> getMaxVScale() const { return None; }
 
   /// Estimate the overhead of scalarizing an instruction. Insert and Extract
   /// are set if the demanded result elements need to be inserted and/or
   /// extracted from vectors.
   unsigned getScalarizationOverhead(VectorType *InTy, const APInt &DemandedElts,
                                     bool Insert, bool Extract) {

llvm/lib/Analysis/TargetTransformInfo.cpp

unsigned TargetTransformInfo::getRegisterClassForType(bool Vector,
                                                       Type *Ty) const {
   return TTIImpl->getRegisterClassForType(Vector, Ty);
 }
 
 const char *TargetTransformInfo::getRegisterClassName(unsigned ClassID) const {
   return TTIImpl->getRegisterClassName(ClassID);
 }
 
-unsigned TargetTransformInfo::getRegisterBitWidth(bool Vector) const {
-  return TTIImpl->getRegisterBitWidth(Vector);
+TypeSize TargetTransformInfo::getRegisterBitWidth(
+    TargetTransformInfo::RegisterKind K) const {
+  return TTIImpl->getRegisterBitWidth(K);
 }
 
 unsigned TargetTransformInfo::getMinVectorRegisterBitWidth() const {
   return TTIImpl->getMinVectorRegisterBitWidth();
 }
 
 Optional<unsigned> TargetTransformInfo::getMaxVScale() const {
   return TTIImpl->getMaxVScale();

llvm/lib/CodeGen/TypePromotion.cpp

bool TypePromotion::runOnFunction(Function &F) {
   SafeWrap.clear();
   bool MadeChange = false;
   const DataLayout &DL = F.getParent()->getDataLayout();
   const TargetMachine &TM = TPC->getTM<TargetMachine>();
   const TargetSubtargetInfo *SubtargetInfo = TM.getSubtargetImpl(F);
   const TargetLowering *TLI = SubtargetInfo->getTargetLowering();
   const TargetTransformInfo &TII =
     getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
-  RegisterBitWidth = TII.getRegisterBitWidth(false);
+  RegisterBitWidth =
+      TII.getRegisterBitWidth(TargetTransformInfo::RGK_Scalar).getFixedSize();
   Ctx = &F.getParent()->getContext();
 
   // Search up from icmps to try to promote their operands.
   for (BasicBlock &BB : F) {
     for (auto &I : BB) {
       if (AllVisited.count(&I))
         continue;
 

llvm/lib/Target/AArch64/AArch64TargetTransformInfo.h

if (Vector) {
       return 0;
     }
     return 31;
   }
 
   unsigned getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
                                  TTI::TargetCostKind CostKind);
 
-  unsigned getRegisterBitWidth(bool Vector) const {
-    if (Vector) {
-      if (ST->hasSVE())
-        return std::max(ST->getMinSVEVectorSizeInBits(), 128u);
-      if (ST->hasNEON())
-        return 128;
-      return 0;
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+    switch (K) {
+    case TargetTransformInfo::RGK_Scalar:
+      return TypeSize::getFixed(64);
+    case TargetTransformInfo::RGK_FixedWidthVector:
+      return TypeSize::getFixed(ST->hasNEON() ? 128 : 0);
+    case TargetTransformInfo::RGK_ScalableVector:
+      return TypeSize::getScalable(
+          ST->hasSVE() ? std::max(ST->getMinSVEVectorSizeInBits(), 128u) : 0);
     }
-    return 64;
+    llvm_unreachable("Unsupported register kind");
   }
 
   unsigned getMinVectorRegisterBitWidth() {
     return ST->getMinVectorRegisterBitWidth();
   }
 
   Optional<unsigned> getMaxVScale() const {
     if (ST->hasSVE())

llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.h

public:
   TTI::PopcntSupportKind getPopcntSupport(unsigned TyWidth) {
     assert(isPowerOf2_32(TyWidth) && "Ty width must be power of 2");
     return TTI::PSK_FastHardware;
   }
 
   unsigned getHardwareNumberOfRegisters(bool Vector) const;
   unsigned getNumberOfRegisters(bool Vector) const;
   unsigned getNumberOfRegisters(unsigned RCID) const;
-  unsigned getRegisterBitWidth(bool Vector) const;
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind Vector) const;
   unsigned getMinVectorRegisterBitWidth() const;
   unsigned getMaximumVF(unsigned ElemWidth, unsigned Opcode) const;
   unsigned getLoadVectorFactor(unsigned VF, unsigned LoadSize,
                                unsigned ChainSizeInBytes,
                                VectorType *VecTy) const;
   unsigned getStoreVectorFactor(unsigned VF, unsigned StoreSize,
                                 unsigned ChainSizeInBytes,
                                 VectorType *VecTy) const;
public:
   const AMDGPUTargetLowering *getTLI() const { return TLI; }
 
   void getUnrollingPreferences(Loop *L, ScalarEvolution &SE,
                                TTI::UnrollingPreferences &UP);
   void getPeelingPreferences(Loop *L, ScalarEvolution &SE,
                              TTI::PeelingPreferences &PP);
   unsigned getHardwareNumberOfRegisters(bool Vec) const;
   unsigned getNumberOfRegisters(bool Vec) const;
-  unsigned getRegisterBitWidth(bool Vector) const;
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind Vector) const;
   unsigned getMinVectorRegisterBitWidth() const;
   unsigned getLoadStoreVecRegBitWidth(unsigned AddrSpace) const;
   bool isLegalToVectorizeMemChain(unsigned ChainSizeInBytes, Align Alignment,
                                   unsigned AddrSpace) const;
   bool isLegalToVectorizeLoadChain(unsigned ChainSizeInBytes, Align Alignment,
                                    unsigned AddrSpace) const;
   bool isLegalToVectorizeStoreChain(unsigned ChainSizeInBytes, Align Alignment,
                                     unsigned AddrSpace) const;
   unsigned getMaxInterleaveFactor(unsigned VF);
   unsigned getCFInstrCost(unsigned Opcode, TTI::TargetCostKind CostKind);
   int getVectorInstrCost(unsigned Opcode, Type *ValTy, unsigned Index);
 };
 
 } // end namespace llvm
 
 #endif // LLVM_LIB_TARGET_AMDGPU_AMDGPUTARGETTRANSFORMINFO_H

llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp

 
 unsigned GCNTTIImpl::getNumberOfRegisters(unsigned RCID) const {
   const SIRegisterInfo *TRI = ST->getRegisterInfo();
   const TargetRegisterClass *RC = TRI->getRegClass(RCID);
   unsigned NumVGPRs = (TRI->getRegSizeInBits(*RC) + 31) / 32;
   return getHardwareNumberOfRegisters(false) / NumVGPRs;
 }
 
-unsigned GCNTTIImpl::getRegisterBitWidth(bool Vector) const {
-  return (Vector && ST->hasPackedFP32Ops()) ? 64 : 32;
+TypeSize
+GCNTTIImpl::getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+  switch (K) {
+  case TargetTransformInfo::RGK_Scalar:
+    return TypeSize::getFixed(32);
+  case TargetTransformInfo::RGK_FixedWidthVector:
+    return TypeSize::getFixed(ST->hasPackedFP32Ops() ? 64 : 32);
+  case TargetTransformInfo::RGK_ScalableVector:
+    return TypeSize::getScalable(0);
+  }
+  llvm_unreachable("Unsupported register kind");
 }
 
 unsigned GCNTTIImpl::getMinVectorRegisterBitWidth() const {
   return 32;
 }
 
 unsigned GCNTTIImpl::getMaximumVF(unsigned ElemWidth, unsigned Opcode) const {
   if (Opcode == Instruction::Load || Opcode == Instruction::Store)

 unsigned R600TTIImpl::getHardwareNumberOfRegisters(bool Vec) const {
   return 4 * 128; // XXX - 4 channels. Should these count as vector instead?
 }
 
 unsigned R600TTIImpl::getNumberOfRegisters(bool Vec) const {
   return getHardwareNumberOfRegisters(Vec);
 }
 
-unsigned R600TTIImpl::getRegisterBitWidth(bool Vector) const {
-  return 32;
+TypeSize
+R600TTIImpl::getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+  return TypeSize::getFixed(32);
 }
 
 unsigned R600TTIImpl::getMinVectorRegisterBitWidth() const {
   return 32;
 }
 
 unsigned R600TTIImpl::getLoadStoreVecRegBitWidth(unsigned AddrSpace) const {
   if (AddrSpace == AMDGPUAS::GLOBAL_ADDRESS ||

llvm/lib/Target/ARM/ARMTargetTransformInfo.h

if (Vector) {
       return 0;
     }
 
     if (ST->isThumb1Only())
       return 8;
     return 13;
   }
 
-  unsigned getRegisterBitWidth(bool Vector) const {
-    if (Vector) {
-      if (ST->hasNEON())
-        return 128;
-      if (ST->hasMVEIntegerOps())
-        return 128;
-      return 0;
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+    switch (K) {
+    case TargetTransformInfo::RGK_Scalar:
+      return TypeSize::getFixed(32);
+    case TargetTransformInfo::RGK_FixedWidthVector:
+      return TypeSize::getFixed((ST->hasNEON() || ST->hasMVEIntegerOps()) ? 128
+                                                                          : 0);
+    case TargetTransformInfo::RGK_ScalableVector:
+      return TypeSize::getScalable(0);
     }
-
-    return 32;
+    llvm_unreachable("Unsupported register kind");
   }
 
   unsigned getMaxInterleaveFactor(unsigned VF) {
     return ST->getMaxInterleaveFactor();
   }
 
   bool isProfitableLSRChainElement(Instruction *I);
 

llvm/lib/Target/Hexagon/HexagonTargetTransformInfo.h

public:
 
   /// @}
 
   /// \name Vector TTI Implementations
   /// @{
 
   unsigned getNumberOfRegisters(bool vector) const;
   unsigned getMaxInterleaveFactor(unsigned VF);
-  unsigned getRegisterBitWidth(bool Vector) const;
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const;
   unsigned getMinVectorRegisterBitWidth() const;
   ElementCount getMinimumVF(unsigned ElemWidth, bool IsScalable) const;
 
   bool shouldMaximizeVectorBandwidth(bool OptSize) const {
     return true;
   }
   bool supportsEfficientVectorElementLoadStore() {
     return false;

llvm/lib/Target/Hexagon/HexagonTargetTransformInfo.cpp

if (Vector)
     return useHVX() ? 32 : 0;
   return 32;
 }
 
 unsigned HexagonTTIImpl::getMaxInterleaveFactor(unsigned VF) {
   return useHVX() ? 2 : 1;
 }
 
-unsigned HexagonTTIImpl::getRegisterBitWidth(bool Vector) const {
-  return Vector ? getMinVectorRegisterBitWidth() : 32;
+TypeSize
+HexagonTTIImpl::getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+  switch (K) {
+  case TargetTransformInfo::RGK_Scalar:
+    return TypeSize::getFixed(32);
+  case TargetTransformInfo::RGK_FixedWidthVector:
+    return TypeSize::getFixed(getMinVectorRegisterBitWidth());
+  case TargetTransformInfo::RGK_ScalableVector:
+    return TypeSize::getScalable(0);
+  }
+
+  llvm_unreachable("Unsupported register kind");
 }
 
 unsigned HexagonTTIImpl::getMinVectorRegisterBitWidth() const {
   return useHVX() ? ST.getVectorLength()*8 : 32;
 }
 
 ElementCount HexagonTTIImpl::getMinimumVF(unsigned ElemWidth,
                                           bool IsScalable) const {
unsigned HexagonTTIImpl::getMemoryOpCost(unsigned Opcode, Type *Src,
   if (Opcode == Instruction::Store)
     return BaseT::getMemoryOpCost(Opcode, Src, Alignment, AddressSpace,
                                   CostKind, I);
 
   if (Src->isVectorTy()) {
     VectorType *VecTy = cast<VectorType>(Src);
     unsigned VecWidth = VecTy->getPrimitiveSizeInBits().getFixedSize();
     if (useHVX() && ST.isTypeForHVX(VecTy)) {
-      unsigned RegWidth = getRegisterBitWidth(true);
+      unsigned RegWidth =
+          getRegisterBitWidth(TargetTransformInfo::RGK_FixedWidthVector)
+              .getFixedSize();
       assert(RegWidth && "Non-zero vector register width expected");
       // Cost of HVX loads.
       if (VecWidth % RegWidth == 0)
         return VecWidth / RegWidth;
       // Cost of constructing HVX vector from scalar loads
       const Align RegAlign(RegWidth / 8);
       if (!Alignment || *Alignment > RegAlign)
         Alignment = RegAlign;

llvm/lib/Target/NVPTX/NVPTXTargetTransformInfo.h

public:
   // We conservatively return 1 here which is just enough to enable the
   // vectorizers but disables heuristics based on the number of registers.
   // FIXME: Return a more reasonable number, while keeping an eye on
   // LoopVectorizer's unrolling heuristics.
   unsigned getNumberOfRegisters(bool Vector) const { return 1; }
 
   // Only <2 x half> should be vectorized, so always return 32 for the vector
   // register size.
-  unsigned getRegisterBitWidth(bool Vector) const { return 32; }
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+    return TypeSize::getFixed(32);
+  }
   unsigned getMinVectorRegisterBitWidth() const { return 32; }
 
   // We don't want to prevent inlining because of target-cpu and -features
   // attributes that were added to newer versions of LLVM/Clang: There are
   // no incompatible functions in PTX, ptxas will throw errors in such cases.
   bool areInlineCompatible(const Function *Caller,
                            const Function *Callee) const {
     return true;

llvm/lib/Target/PowerPC/PPCTargetTransformInfo.h

public:
   bool enableInterleavedAccessVectorization();
 
   enum PPCRegisterClass {
     GPRRC, FPRRC, VRRC, VSXRC
   };
   unsigned getNumberOfRegisters(unsigned ClassID) const;
   unsigned getRegisterClassForType(bool Vector, Type *Ty = nullptr) const;
   const char* getRegisterClassName(unsigned ClassID) const;
-  unsigned getRegisterBitWidth(bool Vector) const;
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const;
   unsigned getCacheLineSize() const override;
   unsigned getPrefetchDistance() const override;
   unsigned getMaxInterleaveFactor(unsigned VF);
   int vectorCostAdjustment(int Cost, unsigned Opcode, Type *Ty1, Type *Ty2);
   int getArithmeticInstrCost(
       unsigned Opcode, Type *Ty,
       TTI::TargetCostKind CostKind = TTI::TCK_RecipThroughput,
       TTI::OperandValueKind Opd1Info = TTI::OK_AnyValue,

llvm/lib/Target/PowerPC/PPCTargetTransformInfo.cpp

default:
       return "PPC::unknown register class";
     case GPRRC:       return "PPC::GPRRC";
     case FPRRC:       return "PPC::FPRRC";
     case VRRC:        return "PPC::VRRC";
     case VSXRC:       return "PPC::VSXRC";
   }
 }
 
-unsigned PPCTTIImpl::getRegisterBitWidth(bool Vector) const {
-  if (Vector) {
-    if (ST->hasAltivec()) return 128;
-    return 0;
+TypeSize
+PPCTTIImpl::getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+  switch (K) {
+  case TargetTransformInfo::RGK_Scalar:
+    return TypeSize::getFixed(ST->isPPC64() ? 64 : 32);
+  case TargetTransformInfo::RGK_FixedWidthVector:
+    return TypeSize::getFixed(ST->hasAltivec() ? 128 : 0);
+  case TargetTransformInfo::RGK_ScalableVector:
+    return TypeSize::getScalable(0);
   }
 
-  if (ST->isPPC64())
-    return 64;
-  return 32;
-
+  llvm_unreachable("Unsupported register kind");
 }
 
 unsigned PPCTTIImpl::getCacheLineSize() const {
   // Check first if the user specified a custom line size.
   if (CacheLineSize.getNumOccurrences() > 0)
     return CacheLineSize;
 
   // Starting with P7 we have a cache line size of 128.

llvm/lib/Target/SystemZ/SystemZTargetTransformInfo.h

public:
   bool isLSRCostLess(TargetTransformInfo::LSRCost &C1,
                      TargetTransformInfo::LSRCost &C2);
   /// @}
 
   /// \name Vector TTI Implementations
   /// @{
 
   unsigned getNumberOfRegisters(unsigned ClassID) const;
-  unsigned getRegisterBitWidth(bool Vector) const;
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const;
 
   unsigned getCacheLineSize() const override { return 256; }
   unsigned getPrefetchDistance() const override { return 4500; }
   unsigned getMinPrefetchStride(unsigned NumMemAccesses,
                                 unsigned NumStridedMemAccesses,
                                 unsigned NumPrefetches,
                                 bool HasCall) const override;
   bool enableWritePrefetching() const override { return true; }

llvm/lib/Target/SystemZ/SystemZTargetTransformInfo.cpp

if (!Vector)
     // Discount the stack pointer.  Also leave out %r0, since it can't
     // be used in an address.
     return 14;
   if (ST->hasVector())
     return 32;
   return 0;
 }
 
-unsigned SystemZTTIImpl::getRegisterBitWidth(bool Vector) const {
-  if (!Vector)
-    return 64;
-  if (ST->hasVector())
-    return 128;
-  return 0;
+TypeSize
+SystemZTTIImpl::getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+  switch (K) {
+  case TargetTransformInfo::RGK_Scalar:
+    return TypeSize::getFixed(64);
+  case TargetTransformInfo::RGK_FixedWidthVector:
+    return TypeSize::getFixed(ST->hasVector() ? 128 : 0);
+  case TargetTransformInfo::RGK_ScalableVector:
+    return TypeSize::getScalable(0);
+  }
+
+  llvm_unreachable("Unsupported register kind");
 }
 
 unsigned SystemZTTIImpl::getMinPrefetchStride(unsigned NumMemAccesses,
                                               unsigned NumStridedMemAccesses,
                                               unsigned NumPrefetches,
                                               bool HasCall) const {
   // Don't prefetch a loop with many far apart accesses.
   if (NumPrefetches > 16)

llvm/lib/Target/VE/VETargetTransformInfo.h

unsigned getNumberOfRegisters(unsigned ClassID) const {
     if (VectorRegs) {
       // TODO report vregs once vector isel is stable.
       return 0;
     }
 
     return 64;
   }
 
-  unsigned getRegisterBitWidth(bool Vector) const {
-    if (Vector) {
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
+    switch (K) {
+    case TargetTransformInfo::RGK_Scalar:
+      return TypeSize::getFixed(64);
+    case TargetTransformInfo::RGK_FixedWidthVector:
       // TODO report vregs once vector isel is stable.
-      return 0;
+      return TypeSize::getFixed(0);
+    case TargetTransformInfo::RGK_ScalableVector:
+      return TypeSize::getScalable(0);
     }
-    return 64;
+
+    llvm_unreachable("Unsupported register kind");
   }
 
   unsigned getMinVectorRegisterBitWidth() const {
     // TODO report vregs once vector isel is stable.
     return 0;
   }
 };
 
 } // namespace llvm
 
 #endif // LLVM_LIB_TARGET_VE_VETARGETTRANSFORMINFO_H

llvm/lib/Target/WebAssembly/WebAssemblyTargetTransformInfo.h

void getUnrollingPreferences(Loop *L, ScalarEvolution &SE,
                                TTI::UnrollingPreferences &UP) const;
 
   /// @}
 
   /// \name Vector TTI Implementations
   /// @{
 
   unsigned getNumberOfRegisters(unsigned ClassID) const;
-  unsigned getRegisterBitWidth(bool Vector) const;
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const;
   unsigned getArithmeticInstrCost(
       unsigned Opcode, Type *Ty,
       TTI::TargetCostKind CostKind = TTI::TCK_SizeAndLatency,
       TTI::OperandValueKind Opd1Info = TTI::OK_AnyValue,
       TTI::OperandValueKind Opd2Info = TTI::OK_AnyValue,
       TTI::OperandValueProperties Opd1PropInfo = TTI::OP_None,
       TTI::OperandValueProperties Opd2PropInfo = TTI::OP_None,
       ArrayRef<const Value *> Args = ArrayRef<const Value *>(),

llvm/lib/Target/WebAssembly/WebAssemblyTargetTransformInfo.cpp

unsigned WebAssemblyTTIImpl::getNumberOfRegisters(unsigned ClassID) const {
   // For SIMD, use at least 16 registers, as a rough guess.
   bool Vector = (ClassID == 1);
   if (Vector)
     Result = std::max(Result, 16u);
 
   return Result;
 }
 
-unsigned WebAssemblyTTIImpl::getRegisterBitWidth(bool Vector) const {
-  if (Vector && getST()->hasSIMD128())
-    return 128;
+TypeSize WebAssemblyTTIImpl::getRegisterBitWidth(
+    TargetTransformInfo::RegisterKind K) const {
+  switch (K) {
+  case TargetTransformInfo::RGK_Scalar:
+    return TypeSize::getFixed(64);
+  case TargetTransformInfo::RGK_FixedWidthVector:
+    return TypeSize::getFixed(getST()->hasSIMD128() ? 128 : 64);
+  case TargetTransformInfo::RGK_ScalableVector:
+    return TypeSize::getScalable(0);
+  }
 
-  return 64;
+  llvm_unreachable("Unsupported register kind");
 }
 
 unsigned WebAssemblyTTIImpl::getArithmeticInstrCost(
     unsigned Opcode, Type *Ty, TTI::TargetCostKind CostKind,
     TTI::OperandValueKind Opd1Info,
     TTI::OperandValueKind Opd2Info, TTI::OperandValueProperties Opd1PropInfo,
     TTI::OperandValueProperties Opd2PropInfo, ArrayRef<const Value *> Args,
     const Instruction *CxtI) {

llvm/lib/Target/X86/X86TargetTransformInfo.h

public:
   llvm::Optional<unsigned> getCacheAssociativity(
     TargetTransformInfo::CacheLevel Level) const override;
   /// @}
 
   /// \name Vector TTI Implementations
   /// @{
 
   unsigned getNumberOfRegisters(unsigned ClassID) const;
-  unsigned getRegisterBitWidth(bool Vector) const;
+  TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const;
   unsigned getLoadStoreVecRegBitWidth(unsigned AS) const;
   unsigned getMaxInterleaveFactor(unsigned VF);
   int getArithmeticInstrCost(
       unsigned Opcode, Type *Ty,
       TTI::TargetCostKind CostKind = TTI::TCK_RecipThroughput,
       TTI::OperandValueKind Opd1Info = TTI::OK_AnyValue,
       TTI::OperandValueKind Opd2Info = TTI::OK_AnyValue,
       TTI::OperandValueProperties Opd1PropInfo = TTI::OP_None,

llvm/lib/Target/X86/X86TargetTransformInfo.cpp

unsigned X86TTIImpl::getNumberOfRegisters(unsigned ClassID) const {
   if (ST->is64Bit()) {
     if (Vector && ST->hasAVX512())
       return 32;
     return 16;
   }
   return 8;
 }
 
-unsigned X86TTIImpl::getRegisterBitWidth(bool Vector) const {
+TypeSize
+X86TTIImpl::getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const {
   unsigned PreferVectorWidth = ST->getPreferVectorWidth();
-  if (Vector) {
+  switch (K) {
+  case TargetTransformInfo::RGK_Scalar:
+    return TypeSize::getFixed(ST->is64Bit() ? 64 : 32);
+  case TargetTransformInfo::RGK_FixedWidthVector:
     if (ST->hasAVX512() && PreferVectorWidth >= 512)
-      return 512;
+      return TypeSize::getFixed(512);
     if (ST->hasAVX() && PreferVectorWidth >= 256)
-      return 256;
+      return TypeSize::getFixed(256);
     if (ST->hasSSE1() && PreferVectorWidth >= 128)
-      return 128;
-    return 0;
+      return TypeSize::getFixed(128);
+    return TypeSize::getFixed(0);
+  case TargetTransformInfo::RGK_ScalableVector:
+    return TypeSize::getScalable(0);
   }
 
-  if (ST->is64Bit())
-    return 64;
-
-  return 32;
+  llvm_unreachable("Unsupported register kind");
 }
 
 unsigned X86TTIImpl::getLoadStoreVecRegBitWidth(unsigned) const {
-  return getRegisterBitWidth(true);
+  return getRegisterBitWidth(TargetTransformInfo::RGK_FixedWidthVector)
+      .getFixedSize();
 }
 
 unsigned X86TTIImpl::getMaxInterleaveFactor(unsigned VF) {
   // If the loop will not be vectorized, don't interleave the loop.
   // Let regular unroll to unroll the loop, which saves the overflow
   // check and memory check cost.
   if (VF == 1)
     return 1;

llvm/lib/Transforms/Scalar/LowerMatrixIntrinsics.cpp

return getNumOps(VT->getScalarType(),
                      cast<FixedVectorType>(VT)->getNumElements());
   }
 
   //
   /// Return the estimated number of vector ops required for an operation on
   /// \p VT * N.
   unsigned getNumOps(Type *ST, unsigned N) {
     return std::ceil((ST->getPrimitiveSizeInBits() * N).getFixedSize() /
-                     double(TTI.getRegisterBitWidth(true)));
+                     double(TTI.getRegisterBitWidth(
+                                   TargetTransformInfo::RGK_FixedWidthVector)
+                                .getFixedSize()));
   }
 
   /// Return the set of vectors that a matrix value is lowered to.
   ///
   /// If we lowered \p MatrixVal, just return the cache result matrix. Otherwise
   /// split the flat vector \p MatrixVal containing a matrix with shape \p SI
   /// into vectors.
   MatrixTy getMatrix(Value *MatrixVal, const ShapeInfo &SI,
public:
   }
 
   /// Compute \p Result += \p A * \p B for input matrices with left-associating
   /// addition.
   void emitMatrixMultiply(MatrixTy &Result, const MatrixTy &A,
                           const MatrixTy &B, bool AllowContraction,
                           IRBuilder<> &Builder, bool isTiled) {
     const unsigned VF = std::max<unsigned>(
-        TTI.getRegisterBitWidth(true) /
+        TTI.getRegisterBitWidth(TargetTransformInfo::RGK_FixedWidthVector)
+                .getFixedSize() /
             Result.getElementType()->getPrimitiveSizeInBits().getFixedSize(),
         1U);
     unsigned R = Result.getNumRows();
     unsigned C = Result.getNumColumns();
     unsigned M = A.getNumColumns();
 
     bool IsFP = Result.getElementType()->isFloatingPointTy();
     assert(A.isColumnMajor() == B.isColumnMajor() &&
bool isFusionProfitable(CallInst *MatMul) {
     ShapeInfo LShape(MatMul->getArgOperand(2), MatMul->getArgOperand(3));
     ShapeInfo RShape(MatMul->getArgOperand(3), MatMul->getArgOperand(4));
 
     const unsigned R = LShape.NumRows;
     const unsigned C = RShape.NumColumns;
     const unsigned M = LShape.NumColumns;
     auto *EltType = cast<VectorType>(MatMul->getType())->getElementType();
 
-    const unsigned VF =
-        std::max<unsigned>(TTI.getRegisterBitWidth(true) /
-                               EltType->getPrimitiveSizeInBits().getFixedSize(),
-                           1U);
+    const unsigned VF = std::max<unsigned>(
+        TTI.getRegisterBitWidth(TargetTransformInfo::RGK_FixedWidthVector)
+                .getFixedSize() /
 
     // Cost model for tiling
     //
     // For tiling to be beneficial, we need reuse either along the R or
     // the C axis.  We vectorize along the R axis so that means at least
     // 3 elements.
     // TODO: Also consider cost of copying if operands alias.
     if (R <= VF && C == 1)

llvm/lib/Transforms/Vectorize/LoopVectorize.cpp

if (UserVF.isNonZero() && !IgnoreScalableUserVF) {
 
     if (Legal->isSafeForAnyVectorWidth())
       return UserVF;
   }
 
   MinBWs = computeMinimumValueSizes(TheLoop->getBlocks(), *DB, &TTI);
   unsigned SmallestType, WidestType;
   std::tie(SmallestType, WidestType) = getSmallestAndWidestTypes();
-  unsigned WidestRegister = TTI.getRegisterBitWidth(true);
+  unsigned WidestRegister =
+      TTI.getRegisterBitWidth(TargetTransformInfo::RGK_FixedWidthVector)
+          .getFixedSize();
 
   // Get the maximum safe dependence distance in bits computed by LAA.
   // It is computed by MaxVF * sizeOf(type) * 8, where type is taken from
   // the memory accesses that is most restrictive (involved in the smallest
   // dependence distance).
   unsigned MaxSafeVectorWidthInBits = Legal->getMaxSafeVectorWidthInBits();
 
   // If the user vectorization factor is legally unsafe, clamp it to a safe
LoopVectorizationPlanner::planInVPlanNativePath(ElementCount UserVF) {
   // Outer loop handling: They may require CFG and instruction level
   // transformations before even evaluating whether vectorization is profitable.
   // Since we cannot modify the incoming IR, we need to build VPlan upfront in
   // the vectorization pipeline.
   if (!OrigLoop->isInnermost()) {
     // If the user doesn't provide a vectorization factor, determine a
     // reasonable one.
     if (UserVF.isZero()) {
-      VF = ElementCount::getFixed(
-          determineVPlanVF(TTI->getRegisterBitWidth(true /* Vector*/), CM));
+      VF = ElementCount::getFixed(determineVPlanVF(
+          TTI->getRegisterBitWidth(TargetTransformInfo::RGK_FixedWidthVector)
+              .getFixedSize(),
+          CM));
       LLVM_DEBUG(dbgs() << "LV: VPlan computed VF " << VF << ".\n");
 
       // Make sure we have a VF > 1 for stress testing.
       if (VPlanBuildStressTest && (VF.isScalar() || VF.isZero())) {
         LLVM_DEBUG(dbgs() << "LV: VPlan stress testing: "
                           << "overriding computed VF.\n");
         VF = ElementCount::getFixed(4);
       }

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

BoUpSLP(Function *Func, ScalarEvolution *Se, TargetTransformInfo *Tti,
     // by a command-line option.
     // TODO: It would be better to limit the vectorization factor based on
     //       data type rather than just register size. For example, x86 AVX has
     //       256-bit registers, but it does not support integer operations
     //       at that width (that requires AVX2).
     if (MaxVectorRegSizeOption.getNumOccurrences())
       MaxVecRegSize = MaxVectorRegSizeOption;
     else
-      MaxVecRegSize = TTI->getRegisterBitWidth(true);
+      MaxVecRegSize =
+          TTI->getRegisterBitWidth(TargetTransformInfo::RGK_FixedWidthVector)
+              .getFixedSize();
 
     if (MinVectorRegSizeOption.getNumOccurrences())
       MinVecRegSize = MinVectorRegSizeOption;
     else
       MinVecRegSize = TTI->getMinVectorRegisterBitWidth();
   }
 
   /// Vectorize the tree that starts with the elements in \p VL.