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      1 //===---- llvm/IRBuilder.h - Builder for LLVM Instructions ------*- C++ -*-===//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 // This file defines the IRBuilder class, which is used as a convenient way
     11 // to create LLVM instructions with a consistent and simplified interface.
     12 //
     13 //===----------------------------------------------------------------------===//
     14 
     15 #ifndef LLVM_IR_IRBUILDER_H
     16 #define LLVM_IR_IRBUILDER_H
     17 
     18 #include "llvm/ADT/ArrayRef.h"
     19 #include "llvm/ADT/None.h"
     20 #include "llvm/ADT/StringRef.h"
     21 #include "llvm/ADT/Twine.h"
     22 #include "llvm/IR/BasicBlock.h"
     23 #include "llvm/IR/Constant.h"
     24 #include "llvm/IR/ConstantFolder.h"
     25 #include "llvm/IR/Constants.h"
     26 #include "llvm/IR/DataLayout.h"
     27 #include "llvm/IR/DebugLoc.h"
     28 #include "llvm/IR/DerivedTypes.h"
     29 #include "llvm/IR/Function.h"
     30 #include "llvm/IR/GlobalVariable.h"
     31 #include "llvm/IR/InstrTypes.h"
     32 #include "llvm/IR/Instruction.h"
     33 #include "llvm/IR/Instructions.h"
     34 #include "llvm/IR/Intrinsics.h"
     35 #include "llvm/IR/LLVMContext.h"
     36 #include "llvm/IR/Module.h"
     37 #include "llvm/IR/Operator.h"
     38 #include "llvm/IR/Type.h"
     39 #include "llvm/IR/Value.h"
     40 #include "llvm/IR/ValueHandle.h"
     41 #include "llvm/Support/AtomicOrdering.h"
     42 #include "llvm/Support/CBindingWrapping.h"
     43 #include "llvm/Support/Casting.h"
     44 #include "llvm-c/Types.h"
     45 #include <cassert>
     46 #include <cstddef>
     47 #include <cstdint>
     48 #include <algorithm>
     49 #include <functional>
     50 
     51 namespace llvm {
     52 
     53 class APInt;
     54 class MDNode;
     55 class Module;
     56 class Use;
     57 
     58 /// \brief This provides the default implementation of the IRBuilder
     59 /// 'InsertHelper' method that is called whenever an instruction is created by
     60 /// IRBuilder and needs to be inserted.
     61 ///
     62 /// By default, this inserts the instruction at the insertion point.
     63 class IRBuilderDefaultInserter {
     64 protected:
     65   void InsertHelper(Instruction *I, const Twine &Name,
     66                     BasicBlock *BB, BasicBlock::iterator InsertPt) const {
     67     if (BB) BB->getInstList().insert(InsertPt, I);
     68     I->setName(Name);
     69   }
     70 };
     71 
     72 /// Provides an 'InsertHelper' that calls a user-provided callback after
     73 /// performing the default insertion.
     74 class IRBuilderCallbackInserter : IRBuilderDefaultInserter {
     75   std::function<void(Instruction *)> Callback;
     76 
     77 public:
     78   IRBuilderCallbackInserter(std::function<void(Instruction *)> Callback)
     79       : Callback(std::move(Callback)) {}
     80 
     81 protected:
     82   void InsertHelper(Instruction *I, const Twine &Name,
     83                     BasicBlock *BB, BasicBlock::iterator InsertPt) const {
     84     IRBuilderDefaultInserter::InsertHelper(I, Name, BB, InsertPt);
     85     Callback(I);
     86   }
     87 };
     88 
     89 /// \brief Common base class shared among various IRBuilders.
     90 class IRBuilderBase {
     91   DebugLoc CurDbgLocation;
     92 
     93 protected:
     94   BasicBlock *BB;
     95   BasicBlock::iterator InsertPt;
     96   LLVMContext &Context;
     97 
     98   MDNode *DefaultFPMathTag;
     99   FastMathFlags FMF;
    100 
    101   ArrayRef<OperandBundleDef> DefaultOperandBundles;
    102 
    103 public:
    104   IRBuilderBase(LLVMContext &context, MDNode *FPMathTag = nullptr,
    105                 ArrayRef<OperandBundleDef> OpBundles = None)
    106       : Context(context), DefaultFPMathTag(FPMathTag),
    107         DefaultOperandBundles(OpBundles) {
    108     ClearInsertionPoint();
    109   }
    110 
    111   //===--------------------------------------------------------------------===//
    112   // Builder configuration methods
    113   //===--------------------------------------------------------------------===//
    114 
    115   /// \brief Clear the insertion point: created instructions will not be
    116   /// inserted into a block.
    117   void ClearInsertionPoint() {
    118     BB = nullptr;
    119     InsertPt = BasicBlock::iterator();
    120   }
    121 
    122   BasicBlock *GetInsertBlock() const { return BB; }
    123   BasicBlock::iterator GetInsertPoint() const { return InsertPt; }
    124   LLVMContext &getContext() const { return Context; }
    125 
    126   /// \brief This specifies that created instructions should be appended to the
    127   /// end of the specified block.
    128   void SetInsertPoint(BasicBlock *TheBB) {
    129     BB = TheBB;
    130     InsertPt = BB->end();
    131   }
    132 
    133   /// \brief This specifies that created instructions should be inserted before
    134   /// the specified instruction.
    135   void SetInsertPoint(Instruction *I) {
    136     BB = I->getParent();
    137     InsertPt = I->getIterator();
    138     assert(InsertPt != BB->end() && "Can't read debug loc from end()");
    139     SetCurrentDebugLocation(I->getDebugLoc());
    140   }
    141 
    142   /// \brief This specifies that created instructions should be inserted at the
    143   /// specified point.
    144   void SetInsertPoint(BasicBlock *TheBB, BasicBlock::iterator IP) {
    145     BB = TheBB;
    146     InsertPt = IP;
    147     if (IP != TheBB->end())
    148       SetCurrentDebugLocation(IP->getDebugLoc());
    149   }
    150 
    151   /// \brief Set location information used by debugging information.
    152   void SetCurrentDebugLocation(DebugLoc L) { CurDbgLocation = std::move(L); }
    153 
    154   /// \brief Get location information used by debugging information.
    155   const DebugLoc &getCurrentDebugLocation() const { return CurDbgLocation; }
    156 
    157   /// \brief If this builder has a current debug location, set it on the
    158   /// specified instruction.
    159   void SetInstDebugLocation(Instruction *I) const {
    160     if (CurDbgLocation)
    161       I->setDebugLoc(CurDbgLocation);
    162   }
    163 
    164   /// \brief Get the return type of the current function that we're emitting
    165   /// into.
    166   Type *getCurrentFunctionReturnType() const;
    167 
    168   /// InsertPoint - A saved insertion point.
    169   class InsertPoint {
    170     BasicBlock *Block = nullptr;
    171     BasicBlock::iterator Point;
    172 
    173   public:
    174     /// \brief Creates a new insertion point which doesn't point to anything.
    175     InsertPoint() = default;
    176 
    177     /// \brief Creates a new insertion point at the given location.
    178     InsertPoint(BasicBlock *InsertBlock, BasicBlock::iterator InsertPoint)
    179       : Block(InsertBlock), Point(InsertPoint) {}
    180 
    181     /// \brief Returns true if this insert point is set.
    182     bool isSet() const { return (Block != nullptr); }
    183 
    184     BasicBlock *getBlock() const { return Block; }
    185     BasicBlock::iterator getPoint() const { return Point; }
    186   };
    187 
    188   /// \brief Returns the current insert point.
    189   InsertPoint saveIP() const {
    190     return InsertPoint(GetInsertBlock(), GetInsertPoint());
    191   }
    192 
    193   /// \brief Returns the current insert point, clearing it in the process.
    194   InsertPoint saveAndClearIP() {
    195     InsertPoint IP(GetInsertBlock(), GetInsertPoint());
    196     ClearInsertionPoint();
    197     return IP;
    198   }
    199 
    200   /// \brief Sets the current insert point to a previously-saved location.
    201   void restoreIP(InsertPoint IP) {
    202     if (IP.isSet())
    203       SetInsertPoint(IP.getBlock(), IP.getPoint());
    204     else
    205       ClearInsertionPoint();
    206   }
    207 
    208   /// \brief Get the floating point math metadata being used.
    209   MDNode *getDefaultFPMathTag() const { return DefaultFPMathTag; }
    210 
    211   /// \brief Get the flags to be applied to created floating point ops
    212   FastMathFlags getFastMathFlags() const { return FMF; }
    213 
    214   /// \brief Clear the fast-math flags.
    215   void clearFastMathFlags() { FMF.clear(); }
    216 
    217   /// \brief Set the floating point math metadata to be used.
    218   void setDefaultFPMathTag(MDNode *FPMathTag) { DefaultFPMathTag = FPMathTag; }
    219 
    220   /// \brief Set the fast-math flags to be used with generated fp-math operators
    221   void setFastMathFlags(FastMathFlags NewFMF) { FMF = NewFMF; }
    222 
    223   //===--------------------------------------------------------------------===//
    224   // RAII helpers.
    225   //===--------------------------------------------------------------------===//
    226 
    227   // \brief RAII object that stores the current insertion point and restores it
    228   // when the object is destroyed. This includes the debug location.
    229   class InsertPointGuard {
    230     IRBuilderBase &Builder;
    231     AssertingVH<BasicBlock> Block;
    232     BasicBlock::iterator Point;
    233     DebugLoc DbgLoc;
    234 
    235   public:
    236     InsertPointGuard(IRBuilderBase &B)
    237         : Builder(B), Block(B.GetInsertBlock()), Point(B.GetInsertPoint()),
    238           DbgLoc(B.getCurrentDebugLocation()) {}
    239 
    240     InsertPointGuard(const InsertPointGuard &) = delete;
    241     InsertPointGuard &operator=(const InsertPointGuard &) = delete;
    242 
    243     ~InsertPointGuard() {
    244       Builder.restoreIP(InsertPoint(Block, Point));
    245       Builder.SetCurrentDebugLocation(DbgLoc);
    246     }
    247   };
    248 
    249   // \brief RAII object that stores the current fast math settings and restores
    250   // them when the object is destroyed.
    251   class FastMathFlagGuard {
    252     IRBuilderBase &Builder;
    253     FastMathFlags FMF;
    254     MDNode *FPMathTag;
    255 
    256   public:
    257     FastMathFlagGuard(IRBuilderBase &B)
    258         : Builder(B), FMF(B.FMF), FPMathTag(B.DefaultFPMathTag) {}
    259 
    260     FastMathFlagGuard(const FastMathFlagGuard &) = delete;
    261     FastMathFlagGuard &operator=(const FastMathFlagGuard &) = delete;
    262 
    263     ~FastMathFlagGuard() {
    264       Builder.FMF = FMF;
    265       Builder.DefaultFPMathTag = FPMathTag;
    266     }
    267   };
    268 
    269   //===--------------------------------------------------------------------===//
    270   // Miscellaneous creation methods.
    271   //===--------------------------------------------------------------------===//
    272 
    273   /// \brief Make a new global variable with initializer type i8*
    274   ///
    275   /// Make a new global variable with an initializer that has array of i8 type
    276   /// filled in with the null terminated string value specified.  The new global
    277   /// variable will be marked mergable with any others of the same contents.  If
    278   /// Name is specified, it is the name of the global variable created.
    279   GlobalVariable *CreateGlobalString(StringRef Str, const Twine &Name = "",
    280                                      unsigned AddressSpace = 0);
    281 
    282   /// \brief Get a constant value representing either true or false.
    283   ConstantInt *getInt1(bool V) {
    284     return ConstantInt::get(getInt1Ty(), V);
    285   }
    286 
    287   /// \brief Get the constant value for i1 true.
    288   ConstantInt *getTrue() {
    289     return ConstantInt::getTrue(Context);
    290   }
    291 
    292   /// \brief Get the constant value for i1 false.
    293   ConstantInt *getFalse() {
    294     return ConstantInt::getFalse(Context);
    295   }
    296 
    297   /// \brief Get a constant 8-bit value.
    298   ConstantInt *getInt8(uint8_t C) {
    299     return ConstantInt::get(getInt8Ty(), C);
    300   }
    301 
    302   /// \brief Get a constant 16-bit value.
    303   ConstantInt *getInt16(uint16_t C) {
    304     return ConstantInt::get(getInt16Ty(), C);
    305   }
    306 
    307   /// \brief Get a constant 32-bit value.
    308   ConstantInt *getInt32(uint32_t C) {
    309     return ConstantInt::get(getInt32Ty(), C);
    310   }
    311 
    312   /// \brief Get a constant 64-bit value.
    313   ConstantInt *getInt64(uint64_t C) {
    314     return ConstantInt::get(getInt64Ty(), C);
    315   }
    316 
    317   /// \brief Get a constant N-bit value, zero extended or truncated from
    318   /// a 64-bit value.
    319   ConstantInt *getIntN(unsigned N, uint64_t C) {
    320     return ConstantInt::get(getIntNTy(N), C);
    321   }
    322 
    323   /// \brief Get a constant integer value.
    324   ConstantInt *getInt(const APInt &AI) {
    325     return ConstantInt::get(Context, AI);
    326   }
    327 
    328   //===--------------------------------------------------------------------===//
    329   // Type creation methods
    330   //===--------------------------------------------------------------------===//
    331 
    332   /// \brief Fetch the type representing a single bit
    333   IntegerType *getInt1Ty() {
    334     return Type::getInt1Ty(Context);
    335   }
    336 
    337   /// \brief Fetch the type representing an 8-bit integer.
    338   IntegerType *getInt8Ty() {
    339     return Type::getInt8Ty(Context);
    340   }
    341 
    342   /// \brief Fetch the type representing a 16-bit integer.
    343   IntegerType *getInt16Ty() {
    344     return Type::getInt16Ty(Context);
    345   }
    346 
    347   /// \brief Fetch the type representing a 32-bit integer.
    348   IntegerType *getInt32Ty() {
    349     return Type::getInt32Ty(Context);
    350   }
    351 
    352   /// \brief Fetch the type representing a 64-bit integer.
    353   IntegerType *getInt64Ty() {
    354     return Type::getInt64Ty(Context);
    355   }
    356 
    357   /// \brief Fetch the type representing a 128-bit integer.
    358   IntegerType *getInt128Ty() { return Type::getInt128Ty(Context); }
    359 
    360   /// \brief Fetch the type representing an N-bit integer.
    361   IntegerType *getIntNTy(unsigned N) {
    362     return Type::getIntNTy(Context, N);
    363   }
    364 
    365   /// \brief Fetch the type representing a 16-bit floating point value.
    366   Type *getHalfTy() {
    367     return Type::getHalfTy(Context);
    368   }
    369 
    370   /// \brief Fetch the type representing a 32-bit floating point value.
    371   Type *getFloatTy() {
    372     return Type::getFloatTy(Context);
    373   }
    374 
    375   /// \brief Fetch the type representing a 64-bit floating point value.
    376   Type *getDoubleTy() {
    377     return Type::getDoubleTy(Context);
    378   }
    379 
    380   /// \brief Fetch the type representing void.
    381   Type *getVoidTy() {
    382     return Type::getVoidTy(Context);
    383   }
    384 
    385   /// \brief Fetch the type representing a pointer to an 8-bit integer value.
    386   PointerType *getInt8PtrTy(unsigned AddrSpace = 0) {
    387     return Type::getInt8PtrTy(Context, AddrSpace);
    388   }
    389 
    390   /// \brief Fetch the type representing a pointer to an integer value.
    391   IntegerType *getIntPtrTy(const DataLayout &DL, unsigned AddrSpace = 0) {
    392     return DL.getIntPtrType(Context, AddrSpace);
    393   }
    394 
    395   //===--------------------------------------------------------------------===//
    396   // Intrinsic creation methods
    397   //===--------------------------------------------------------------------===//
    398 
    399   /// \brief Create and insert a memset to the specified pointer and the
    400   /// specified value.
    401   ///
    402   /// If the pointer isn't an i8*, it will be converted. If a TBAA tag is
    403   /// specified, it will be added to the instruction. Likewise with alias.scope
    404   /// and noalias tags.
    405   CallInst *CreateMemSet(Value *Ptr, Value *Val, uint64_t Size, unsigned Align,
    406                          bool isVolatile = false, MDNode *TBAATag = nullptr,
    407                          MDNode *ScopeTag = nullptr,
    408                          MDNode *NoAliasTag = nullptr) {
    409     return CreateMemSet(Ptr, Val, getInt64(Size), Align, isVolatile,
    410                         TBAATag, ScopeTag, NoAliasTag);
    411   }
    412 
    413   CallInst *CreateMemSet(Value *Ptr, Value *Val, Value *Size, unsigned Align,
    414                          bool isVolatile = false, MDNode *TBAATag = nullptr,
    415                          MDNode *ScopeTag = nullptr,
    416                          MDNode *NoAliasTag = nullptr);
    417 
    418   /// \brief Create and insert a memcpy between the specified pointers.
    419   ///
    420   /// If the pointers aren't i8*, they will be converted.  If a TBAA tag is
    421   /// specified, it will be added to the instruction. Likewise with alias.scope
    422   /// and noalias tags.
    423   CallInst *CreateMemCpy(Value *Dst, Value *Src, uint64_t Size, unsigned Align,
    424                          bool isVolatile = false, MDNode *TBAATag = nullptr,
    425                          MDNode *TBAAStructTag = nullptr,
    426                          MDNode *ScopeTag = nullptr,
    427                          MDNode *NoAliasTag = nullptr) {
    428     return CreateMemCpy(Dst, Src, getInt64(Size), Align, isVolatile, TBAATag,
    429                         TBAAStructTag, ScopeTag, NoAliasTag);
    430   }
    431 
    432   CallInst *CreateMemCpy(Value *Dst, Value *Src, Value *Size, unsigned Align,
    433                          bool isVolatile = false, MDNode *TBAATag = nullptr,
    434                          MDNode *TBAAStructTag = nullptr,
    435                          MDNode *ScopeTag = nullptr,
    436                          MDNode *NoAliasTag = nullptr);
    437 
    438   /// \brief Create and insert a memmove between the specified
    439   /// pointers.
    440   ///
    441   /// If the pointers aren't i8*, they will be converted.  If a TBAA tag is
    442   /// specified, it will be added to the instruction. Likewise with alias.scope
    443   /// and noalias tags.
    444   CallInst *CreateMemMove(Value *Dst, Value *Src, uint64_t Size, unsigned Align,
    445                           bool isVolatile = false, MDNode *TBAATag = nullptr,
    446                           MDNode *ScopeTag = nullptr,
    447                           MDNode *NoAliasTag = nullptr) {
    448     return CreateMemMove(Dst, Src, getInt64(Size), Align, isVolatile,
    449                          TBAATag, ScopeTag, NoAliasTag);
    450   }
    451 
    452   CallInst *CreateMemMove(Value *Dst, Value *Src, Value *Size, unsigned Align,
    453                           bool isVolatile = false, MDNode *TBAATag = nullptr,
    454                           MDNode *ScopeTag = nullptr,
    455                           MDNode *NoAliasTag = nullptr);
    456 
    457   /// \brief Create a lifetime.start intrinsic.
    458   ///
    459   /// If the pointer isn't i8* it will be converted.
    460   CallInst *CreateLifetimeStart(Value *Ptr, ConstantInt *Size = nullptr);
    461 
    462   /// \brief Create a lifetime.end intrinsic.
    463   ///
    464   /// If the pointer isn't i8* it will be converted.
    465   CallInst *CreateLifetimeEnd(Value *Ptr, ConstantInt *Size = nullptr);
    466 
    467   /// Create a call to invariant.start intrinsic.
    468   ///
    469   /// If the pointer isn't i8* it will be converted.
    470   CallInst *CreateInvariantStart(Value *Ptr, ConstantInt *Size = nullptr);
    471 
    472   /// \brief Create a call to Masked Load intrinsic
    473   CallInst *CreateMaskedLoad(Value *Ptr, unsigned Align, Value *Mask,
    474                              Value *PassThru = nullptr, const Twine &Name = "");
    475 
    476   /// \brief Create a call to Masked Store intrinsic
    477   CallInst *CreateMaskedStore(Value *Val, Value *Ptr, unsigned Align,
    478                               Value *Mask);
    479 
    480   /// \brief Create a call to Masked Gather intrinsic
    481   CallInst *CreateMaskedGather(Value *Ptrs, unsigned Align,
    482                                Value *Mask = nullptr,
    483                                Value *PassThru = nullptr,
    484                                const Twine& Name = "");
    485 
    486   /// \brief Create a call to Masked Scatter intrinsic
    487   CallInst *CreateMaskedScatter(Value *Val, Value *Ptrs, unsigned Align,
    488                                 Value *Mask = nullptr);
    489 
    490   /// \brief Create an assume intrinsic call that allows the optimizer to
    491   /// assume that the provided condition will be true.
    492   CallInst *CreateAssumption(Value *Cond);
    493 
    494   /// \brief Create a call to the experimental.gc.statepoint intrinsic to
    495   /// start a new statepoint sequence.
    496   CallInst *CreateGCStatepointCall(uint64_t ID, uint32_t NumPatchBytes,
    497                                    Value *ActualCallee,
    498                                    ArrayRef<Value *> CallArgs,
    499                                    ArrayRef<Value *> DeoptArgs,
    500                                    ArrayRef<Value *> GCArgs,
    501                                    const Twine &Name = "");
    502 
    503   /// \brief Create a call to the experimental.gc.statepoint intrinsic to
    504   /// start a new statepoint sequence.
    505   CallInst *CreateGCStatepointCall(uint64_t ID, uint32_t NumPatchBytes,
    506                                    Value *ActualCallee, uint32_t Flags,
    507                                    ArrayRef<Use> CallArgs,
    508                                    ArrayRef<Use> TransitionArgs,
    509                                    ArrayRef<Use> DeoptArgs,
    510                                    ArrayRef<Value *> GCArgs,
    511                                    const Twine &Name = "");
    512 
    513   // \brief Conveninence function for the common case when CallArgs are filled
    514   // in using makeArrayRef(CS.arg_begin(), CS.arg_end()); Use needs to be
    515   // .get()'ed to get the Value pointer.
    516   CallInst *CreateGCStatepointCall(uint64_t ID, uint32_t NumPatchBytes,
    517                                    Value *ActualCallee, ArrayRef<Use> CallArgs,
    518                                    ArrayRef<Value *> DeoptArgs,
    519                                    ArrayRef<Value *> GCArgs,
    520                                    const Twine &Name = "");
    521 
    522   /// brief Create an invoke to the experimental.gc.statepoint intrinsic to
    523   /// start a new statepoint sequence.
    524   InvokeInst *
    525   CreateGCStatepointInvoke(uint64_t ID, uint32_t NumPatchBytes,
    526                            Value *ActualInvokee, BasicBlock *NormalDest,
    527                            BasicBlock *UnwindDest, ArrayRef<Value *> InvokeArgs,
    528                            ArrayRef<Value *> DeoptArgs,
    529                            ArrayRef<Value *> GCArgs, const Twine &Name = "");
    530 
    531   /// brief Create an invoke to the experimental.gc.statepoint intrinsic to
    532   /// start a new statepoint sequence.
    533   InvokeInst *CreateGCStatepointInvoke(
    534       uint64_t ID, uint32_t NumPatchBytes, Value *ActualInvokee,
    535       BasicBlock *NormalDest, BasicBlock *UnwindDest, uint32_t Flags,
    536       ArrayRef<Use> InvokeArgs, ArrayRef<Use> TransitionArgs,
    537       ArrayRef<Use> DeoptArgs, ArrayRef<Value *> GCArgs,
    538       const Twine &Name = "");
    539 
    540   // Conveninence function for the common case when CallArgs are filled in using
    541   // makeArrayRef(CS.arg_begin(), CS.arg_end()); Use needs to be .get()'ed to
    542   // get the Value *.
    543   InvokeInst *
    544   CreateGCStatepointInvoke(uint64_t ID, uint32_t NumPatchBytes,
    545                            Value *ActualInvokee, BasicBlock *NormalDest,
    546                            BasicBlock *UnwindDest, ArrayRef<Use> InvokeArgs,
    547                            ArrayRef<Value *> DeoptArgs,
    548                            ArrayRef<Value *> GCArgs, const Twine &Name = "");
    549 
    550   /// \brief Create a call to the experimental.gc.result intrinsic to extract
    551   /// the result from a call wrapped in a statepoint.
    552   CallInst *CreateGCResult(Instruction *Statepoint,
    553                            Type *ResultType,
    554                            const Twine &Name = "");
    555 
    556   /// \brief Create a call to the experimental.gc.relocate intrinsics to
    557   /// project the relocated value of one pointer from the statepoint.
    558   CallInst *CreateGCRelocate(Instruction *Statepoint,
    559                              int BaseOffset,
    560                              int DerivedOffset,
    561                              Type *ResultType,
    562                              const Twine &Name = "");
    563 
    564   /// Create a call to intrinsic \p ID with 2 operands which is mangled on the
    565   /// first type.
    566   CallInst *CreateBinaryIntrinsic(Intrinsic::ID ID,
    567                                   Value *LHS, Value *RHS,
    568                                   const Twine &Name = "");
    569 
    570   /// Create call to the minnum intrinsic.
    571   CallInst *CreateMinNum(Value *LHS, Value *RHS, const Twine &Name = "") {
    572     return CreateBinaryIntrinsic(Intrinsic::minnum, LHS, RHS, Name);
    573   }
    574 
    575   /// Create call to the maxnum intrinsic.
    576   CallInst *CreateMaxNum(Value *LHS, Value *RHS, const Twine &Name = "") {
    577     return CreateBinaryIntrinsic(Intrinsic::minnum, LHS, RHS, Name);
    578   }
    579 
    580 private:
    581   /// \brief Create a call to a masked intrinsic with given Id.
    582   CallInst *CreateMaskedIntrinsic(Intrinsic::ID Id, ArrayRef<Value *> Ops,
    583                                   ArrayRef<Type *> OverloadedTypes,
    584                                   const Twine &Name = "");
    585 
    586   Value *getCastedInt8PtrValue(Value *Ptr);
    587 };
    588 
    589 /// \brief This provides a uniform API for creating instructions and inserting
    590 /// them into a basic block: either at the end of a BasicBlock, or at a specific
    591 /// iterator location in a block.
    592 ///
    593 /// Note that the builder does not expose the full generality of LLVM
    594 /// instructions.  For access to extra instruction properties, use the mutators
    595 /// (e.g. setVolatile) on the instructions after they have been
    596 /// created. Convenience state exists to specify fast-math flags and fp-math
    597 /// tags.
    598 ///
    599 /// The first template argument specifies a class to use for creating constants.
    600 /// This defaults to creating minimally folded constants.  The second template
    601 /// argument allows clients to specify custom insertion hooks that are called on
    602 /// every newly created insertion.
    603 template <typename T = ConstantFolder,
    604           typename Inserter = IRBuilderDefaultInserter>
    605 class IRBuilder : public IRBuilderBase, public Inserter {
    606   T Folder;
    607 
    608 public:
    609   IRBuilder(LLVMContext &C, const T &F, Inserter I = Inserter(),
    610             MDNode *FPMathTag = nullptr,
    611             ArrayRef<OperandBundleDef> OpBundles = None)
    612       : IRBuilderBase(C, FPMathTag, OpBundles), Inserter(std::move(I)),
    613         Folder(F) {}
    614 
    615   explicit IRBuilder(LLVMContext &C, MDNode *FPMathTag = nullptr,
    616                      ArrayRef<OperandBundleDef> OpBundles = None)
    617       : IRBuilderBase(C, FPMathTag, OpBundles), Folder() {}
    618 
    619   explicit IRBuilder(BasicBlock *TheBB, const T &F, MDNode *FPMathTag = nullptr,
    620                      ArrayRef<OperandBundleDef> OpBundles = None)
    621       : IRBuilderBase(TheBB->getContext(), FPMathTag, OpBundles), Folder(F) {
    622     SetInsertPoint(TheBB);
    623   }
    624 
    625   explicit IRBuilder(BasicBlock *TheBB, MDNode *FPMathTag = nullptr,
    626                      ArrayRef<OperandBundleDef> OpBundles = None)
    627       : IRBuilderBase(TheBB->getContext(), FPMathTag, OpBundles), Folder() {
    628     SetInsertPoint(TheBB);
    629   }
    630 
    631   explicit IRBuilder(Instruction *IP, MDNode *FPMathTag = nullptr,
    632                      ArrayRef<OperandBundleDef> OpBundles = None)
    633       : IRBuilderBase(IP->getContext(), FPMathTag, OpBundles), Folder() {
    634     SetInsertPoint(IP);
    635   }
    636 
    637   IRBuilder(BasicBlock *TheBB, BasicBlock::iterator IP, const T &F,
    638             MDNode *FPMathTag = nullptr,
    639             ArrayRef<OperandBundleDef> OpBundles = None)
    640       : IRBuilderBase(TheBB->getContext(), FPMathTag, OpBundles), Folder(F) {
    641     SetInsertPoint(TheBB, IP);
    642   }
    643 
    644   IRBuilder(BasicBlock *TheBB, BasicBlock::iterator IP,
    645             MDNode *FPMathTag = nullptr,
    646             ArrayRef<OperandBundleDef> OpBundles = None)
    647       : IRBuilderBase(TheBB->getContext(), FPMathTag, OpBundles), Folder() {
    648     SetInsertPoint(TheBB, IP);
    649   }
    650 
    651   /// \brief Get the constant folder being used.
    652   const T &getFolder() { return Folder; }
    653 
    654   /// \brief Insert and return the specified instruction.
    655   template<typename InstTy>
    656   InstTy *Insert(InstTy *I, const Twine &Name = "") const {
    657     this->InsertHelper(I, Name, BB, InsertPt);
    658     this->SetInstDebugLocation(I);
    659     return I;
    660   }
    661 
    662   /// \brief No-op overload to handle constants.
    663   Constant *Insert(Constant *C, const Twine& = "") const {
    664     return C;
    665   }
    666 
    667   //===--------------------------------------------------------------------===//
    668   // Instruction creation methods: Terminators
    669   //===--------------------------------------------------------------------===//
    670 
    671 private:
    672   /// \brief Helper to add branch weight and unpredictable metadata onto an
    673   /// instruction.
    674   /// \returns The annotated instruction.
    675   template <typename InstTy>
    676   InstTy *addBranchMetadata(InstTy *I, MDNode *Weights, MDNode *Unpredictable) {
    677     if (Weights)
    678       I->setMetadata(LLVMContext::MD_prof, Weights);
    679     if (Unpredictable)
    680       I->setMetadata(LLVMContext::MD_unpredictable, Unpredictable);
    681     return I;
    682   }
    683 
    684 public:
    685   /// \brief Create a 'ret void' instruction.
    686   ReturnInst *CreateRetVoid() {
    687     return Insert(ReturnInst::Create(Context));
    688   }
    689 
    690   /// \brief Create a 'ret <val>' instruction.
    691   ReturnInst *CreateRet(Value *V) {
    692     return Insert(ReturnInst::Create(Context, V));
    693   }
    694 
    695   /// \brief Create a sequence of N insertvalue instructions,
    696   /// with one Value from the retVals array each, that build a aggregate
    697   /// return value one value at a time, and a ret instruction to return
    698   /// the resulting aggregate value.
    699   ///
    700   /// This is a convenience function for code that uses aggregate return values
    701   /// as a vehicle for having multiple return values.
    702   ReturnInst *CreateAggregateRet(Value *const *retVals, unsigned N) {
    703     Value *V = UndefValue::get(getCurrentFunctionReturnType());
    704     for (unsigned i = 0; i != N; ++i)
    705       V = CreateInsertValue(V, retVals[i], i, "mrv");
    706     return Insert(ReturnInst::Create(Context, V));
    707   }
    708 
    709   /// \brief Create an unconditional 'br label X' instruction.
    710   BranchInst *CreateBr(BasicBlock *Dest) {
    711     return Insert(BranchInst::Create(Dest));
    712   }
    713 
    714   /// \brief Create a conditional 'br Cond, TrueDest, FalseDest'
    715   /// instruction.
    716   BranchInst *CreateCondBr(Value *Cond, BasicBlock *True, BasicBlock *False,
    717                            MDNode *BranchWeights = nullptr,
    718                            MDNode *Unpredictable = nullptr) {
    719     return Insert(addBranchMetadata(BranchInst::Create(True, False, Cond),
    720                                     BranchWeights, Unpredictable));
    721   }
    722 
    723   /// \brief Create a conditional 'br Cond, TrueDest, FalseDest'
    724   /// instruction. Copy branch meta data if available.
    725   BranchInst *CreateCondBr(Value *Cond, BasicBlock *True, BasicBlock *False,
    726                            Instruction *MDSrc) {
    727     BranchInst *Br = BranchInst::Create(True, False, Cond);
    728     if (MDSrc) {
    729       unsigned WL[4] = {LLVMContext::MD_prof, LLVMContext::MD_unpredictable,
    730                         LLVMContext::MD_make_implicit, LLVMContext::MD_dbg};
    731       Br->copyMetadata(*MDSrc, makeArrayRef(&WL[0], 4));
    732     }
    733     return Insert(Br);
    734   }
    735 
    736   /// \brief Create a switch instruction with the specified value, default dest,
    737   /// and with a hint for the number of cases that will be added (for efficient
    738   /// allocation).
    739   SwitchInst *CreateSwitch(Value *V, BasicBlock *Dest, unsigned NumCases = 10,
    740                            MDNode *BranchWeights = nullptr,
    741                            MDNode *Unpredictable = nullptr) {
    742     return Insert(addBranchMetadata(SwitchInst::Create(V, Dest, NumCases),
    743                                     BranchWeights, Unpredictable));
    744   }
    745 
    746   /// \brief Create an indirect branch instruction with the specified address
    747   /// operand, with an optional hint for the number of destinations that will be
    748   /// added (for efficient allocation).
    749   IndirectBrInst *CreateIndirectBr(Value *Addr, unsigned NumDests = 10) {
    750     return Insert(IndirectBrInst::Create(Addr, NumDests));
    751   }
    752 
    753   /// \brief Create an invoke instruction.
    754   InvokeInst *CreateInvoke(Value *Callee, BasicBlock *NormalDest,
    755                            BasicBlock *UnwindDest,
    756                            ArrayRef<Value *> Args = None,
    757                            const Twine &Name = "") {
    758     return Insert(InvokeInst::Create(Callee, NormalDest, UnwindDest, Args),
    759                   Name);
    760   }
    761   InvokeInst *CreateInvoke(Value *Callee, BasicBlock *NormalDest,
    762                            BasicBlock *UnwindDest, ArrayRef<Value *> Args,
    763                            ArrayRef<OperandBundleDef> OpBundles,
    764                            const Twine &Name = "") {
    765     return Insert(InvokeInst::Create(Callee, NormalDest, UnwindDest, Args,
    766                                      OpBundles), Name);
    767   }
    768 
    769   ResumeInst *CreateResume(Value *Exn) {
    770     return Insert(ResumeInst::Create(Exn));
    771   }
    772 
    773   CleanupReturnInst *CreateCleanupRet(CleanupPadInst *CleanupPad,
    774                                       BasicBlock *UnwindBB = nullptr) {
    775     return Insert(CleanupReturnInst::Create(CleanupPad, UnwindBB));
    776   }
    777 
    778   CatchSwitchInst *CreateCatchSwitch(Value *ParentPad, BasicBlock *UnwindBB,
    779                                      unsigned NumHandlers,
    780                                      const Twine &Name = "") {
    781     return Insert(CatchSwitchInst::Create(ParentPad, UnwindBB, NumHandlers),
    782                   Name);
    783   }
    784 
    785   CatchPadInst *CreateCatchPad(Value *ParentPad, ArrayRef<Value *> Args,
    786                                const Twine &Name = "") {
    787     return Insert(CatchPadInst::Create(ParentPad, Args), Name);
    788   }
    789 
    790   CleanupPadInst *CreateCleanupPad(Value *ParentPad,
    791                                    ArrayRef<Value *> Args = None,
    792                                    const Twine &Name = "") {
    793     return Insert(CleanupPadInst::Create(ParentPad, Args), Name);
    794   }
    795 
    796   CatchReturnInst *CreateCatchRet(CatchPadInst *CatchPad, BasicBlock *BB) {
    797     return Insert(CatchReturnInst::Create(CatchPad, BB));
    798   }
    799 
    800   UnreachableInst *CreateUnreachable() {
    801     return Insert(new UnreachableInst(Context));
    802   }
    803 
    804   //===--------------------------------------------------------------------===//
    805   // Instruction creation methods: Binary Operators
    806   //===--------------------------------------------------------------------===//
    807 private:
    808   BinaryOperator *CreateInsertNUWNSWBinOp(BinaryOperator::BinaryOps Opc,
    809                                           Value *LHS, Value *RHS,
    810                                           const Twine &Name,
    811                                           bool HasNUW, bool HasNSW) {
    812     BinaryOperator *BO = Insert(BinaryOperator::Create(Opc, LHS, RHS), Name);
    813     if (HasNUW) BO->setHasNoUnsignedWrap();
    814     if (HasNSW) BO->setHasNoSignedWrap();
    815     return BO;
    816   }
    817 
    818   Instruction *AddFPMathAttributes(Instruction *I,
    819                                    MDNode *FPMathTag,
    820                                    FastMathFlags FMF) const {
    821     if (!FPMathTag)
    822       FPMathTag = DefaultFPMathTag;
    823     if (FPMathTag)
    824       I->setMetadata(LLVMContext::MD_fpmath, FPMathTag);
    825     I->setFastMathFlags(FMF);
    826     return I;
    827   }
    828 
    829 public:
    830   Value *CreateAdd(Value *LHS, Value *RHS, const Twine &Name = "",
    831                    bool HasNUW = false, bool HasNSW = false) {
    832     if (Constant *LC = dyn_cast<Constant>(LHS))
    833       if (Constant *RC = dyn_cast<Constant>(RHS))
    834         return Insert(Folder.CreateAdd(LC, RC, HasNUW, HasNSW), Name);
    835     return CreateInsertNUWNSWBinOp(Instruction::Add, LHS, RHS, Name,
    836                                    HasNUW, HasNSW);
    837   }
    838   Value *CreateNSWAdd(Value *LHS, Value *RHS, const Twine &Name = "") {
    839     return CreateAdd(LHS, RHS, Name, false, true);
    840   }
    841   Value *CreateNUWAdd(Value *LHS, Value *RHS, const Twine &Name = "") {
    842     return CreateAdd(LHS, RHS, Name, true, false);
    843   }
    844   Value *CreateFAdd(Value *LHS, Value *RHS, const Twine &Name = "",
    845                     MDNode *FPMathTag = nullptr) {
    846     if (Constant *LC = dyn_cast<Constant>(LHS))
    847       if (Constant *RC = dyn_cast<Constant>(RHS))
    848         return Insert(Folder.CreateFAdd(LC, RC), Name);
    849     return Insert(AddFPMathAttributes(BinaryOperator::CreateFAdd(LHS, RHS),
    850                                       FPMathTag, FMF), Name);
    851   }
    852   Value *CreateSub(Value *LHS, Value *RHS, const Twine &Name = "",
    853                    bool HasNUW = false, bool HasNSW = false) {
    854     if (Constant *LC = dyn_cast<Constant>(LHS))
    855       if (Constant *RC = dyn_cast<Constant>(RHS))
    856         return Insert(Folder.CreateSub(LC, RC, HasNUW, HasNSW), Name);
    857     return CreateInsertNUWNSWBinOp(Instruction::Sub, LHS, RHS, Name,
    858                                    HasNUW, HasNSW);
    859   }
    860   Value *CreateNSWSub(Value *LHS, Value *RHS, const Twine &Name = "") {
    861     return CreateSub(LHS, RHS, Name, false, true);
    862   }
    863   Value *CreateNUWSub(Value *LHS, Value *RHS, const Twine &Name = "") {
    864     return CreateSub(LHS, RHS, Name, true, false);
    865   }
    866   Value *CreateFSub(Value *LHS, Value *RHS, const Twine &Name = "",
    867                     MDNode *FPMathTag = nullptr) {
    868     if (Constant *LC = dyn_cast<Constant>(LHS))
    869       if (Constant *RC = dyn_cast<Constant>(RHS))
    870         return Insert(Folder.CreateFSub(LC, RC), Name);
    871     return Insert(AddFPMathAttributes(BinaryOperator::CreateFSub(LHS, RHS),
    872                                       FPMathTag, FMF), Name);
    873   }
    874   Value *CreateMul(Value *LHS, Value *RHS, const Twine &Name = "",
    875                    bool HasNUW = false, bool HasNSW = false) {
    876     if (Constant *LC = dyn_cast<Constant>(LHS))
    877       if (Constant *RC = dyn_cast<Constant>(RHS))
    878         return Insert(Folder.CreateMul(LC, RC, HasNUW, HasNSW), Name);
    879     return CreateInsertNUWNSWBinOp(Instruction::Mul, LHS, RHS, Name,
    880                                    HasNUW, HasNSW);
    881   }
    882   Value *CreateNSWMul(Value *LHS, Value *RHS, const Twine &Name = "") {
    883     return CreateMul(LHS, RHS, Name, false, true);
    884   }
    885   Value *CreateNUWMul(Value *LHS, Value *RHS, const Twine &Name = "") {
    886     return CreateMul(LHS, RHS, Name, true, false);
    887   }
    888   Value *CreateFMul(Value *LHS, Value *RHS, const Twine &Name = "",
    889                     MDNode *FPMathTag = nullptr) {
    890     if (Constant *LC = dyn_cast<Constant>(LHS))
    891       if (Constant *RC = dyn_cast<Constant>(RHS))
    892         return Insert(Folder.CreateFMul(LC, RC), Name);
    893     return Insert(AddFPMathAttributes(BinaryOperator::CreateFMul(LHS, RHS),
    894                                       FPMathTag, FMF), Name);
    895   }
    896   Value *CreateUDiv(Value *LHS, Value *RHS, const Twine &Name = "",
    897                     bool isExact = false) {
    898     if (Constant *LC = dyn_cast<Constant>(LHS))
    899       if (Constant *RC = dyn_cast<Constant>(RHS))
    900         return Insert(Folder.CreateUDiv(LC, RC, isExact), Name);
    901     if (!isExact)
    902       return Insert(BinaryOperator::CreateUDiv(LHS, RHS), Name);
    903     return Insert(BinaryOperator::CreateExactUDiv(LHS, RHS), Name);
    904   }
    905   Value *CreateExactUDiv(Value *LHS, Value *RHS, const Twine &Name = "") {
    906     return CreateUDiv(LHS, RHS, Name, true);
    907   }
    908   Value *CreateSDiv(Value *LHS, Value *RHS, const Twine &Name = "",
    909                     bool isExact = false) {
    910     if (Constant *LC = dyn_cast<Constant>(LHS))
    911       if (Constant *RC = dyn_cast<Constant>(RHS))
    912         return Insert(Folder.CreateSDiv(LC, RC, isExact), Name);
    913     if (!isExact)
    914       return Insert(BinaryOperator::CreateSDiv(LHS, RHS), Name);
    915     return Insert(BinaryOperator::CreateExactSDiv(LHS, RHS), Name);
    916   }
    917   Value *CreateExactSDiv(Value *LHS, Value *RHS, const Twine &Name = "") {
    918     return CreateSDiv(LHS, RHS, Name, true);
    919   }
    920   Value *CreateFDiv(Value *LHS, Value *RHS, const Twine &Name = "",
    921                     MDNode *FPMathTag = nullptr) {
    922     if (Constant *LC = dyn_cast<Constant>(LHS))
    923       if (Constant *RC = dyn_cast<Constant>(RHS))
    924         return Insert(Folder.CreateFDiv(LC, RC), Name);
    925     return Insert(AddFPMathAttributes(BinaryOperator::CreateFDiv(LHS, RHS),
    926                                       FPMathTag, FMF), Name);
    927   }
    928   Value *CreateURem(Value *LHS, Value *RHS, const Twine &Name = "") {
    929     if (Constant *LC = dyn_cast<Constant>(LHS))
    930       if (Constant *RC = dyn_cast<Constant>(RHS))
    931         return Insert(Folder.CreateURem(LC, RC), Name);
    932     return Insert(BinaryOperator::CreateURem(LHS, RHS), Name);
    933   }
    934   Value *CreateSRem(Value *LHS, Value *RHS, const Twine &Name = "") {
    935     if (Constant *LC = dyn_cast<Constant>(LHS))
    936       if (Constant *RC = dyn_cast<Constant>(RHS))
    937         return Insert(Folder.CreateSRem(LC, RC), Name);
    938     return Insert(BinaryOperator::CreateSRem(LHS, RHS), Name);
    939   }
    940   Value *CreateFRem(Value *LHS, Value *RHS, const Twine &Name = "",
    941                     MDNode *FPMathTag = nullptr) {
    942     if (Constant *LC = dyn_cast<Constant>(LHS))
    943       if (Constant *RC = dyn_cast<Constant>(RHS))
    944         return Insert(Folder.CreateFRem(LC, RC), Name);
    945     return Insert(AddFPMathAttributes(BinaryOperator::CreateFRem(LHS, RHS),
    946                                       FPMathTag, FMF), Name);
    947   }
    948 
    949   Value *CreateShl(Value *LHS, Value *RHS, const Twine &Name = "",
    950                    bool HasNUW = false, bool HasNSW = false) {
    951     if (Constant *LC = dyn_cast<Constant>(LHS))
    952       if (Constant *RC = dyn_cast<Constant>(RHS))
    953         return Insert(Folder.CreateShl(LC, RC, HasNUW, HasNSW), Name);
    954     return CreateInsertNUWNSWBinOp(Instruction::Shl, LHS, RHS, Name,
    955                                    HasNUW, HasNSW);
    956   }
    957   Value *CreateShl(Value *LHS, const APInt &RHS, const Twine &Name = "",
    958                    bool HasNUW = false, bool HasNSW = false) {
    959     return CreateShl(LHS, ConstantInt::get(LHS->getType(), RHS), Name,
    960                      HasNUW, HasNSW);
    961   }
    962   Value *CreateShl(Value *LHS, uint64_t RHS, const Twine &Name = "",
    963                    bool HasNUW = false, bool HasNSW = false) {
    964     return CreateShl(LHS, ConstantInt::get(LHS->getType(), RHS), Name,
    965                      HasNUW, HasNSW);
    966   }
    967 
    968   Value *CreateLShr(Value *LHS, Value *RHS, const Twine &Name = "",
    969                     bool isExact = false) {
    970     if (Constant *LC = dyn_cast<Constant>(LHS))
    971       if (Constant *RC = dyn_cast<Constant>(RHS))
    972         return Insert(Folder.CreateLShr(LC, RC, isExact), Name);
    973     if (!isExact)
    974       return Insert(BinaryOperator::CreateLShr(LHS, RHS), Name);
    975     return Insert(BinaryOperator::CreateExactLShr(LHS, RHS), Name);
    976   }
    977   Value *CreateLShr(Value *LHS, const APInt &RHS, const Twine &Name = "",
    978                     bool isExact = false) {
    979     return CreateLShr(LHS, ConstantInt::get(LHS->getType(), RHS), Name,isExact);
    980   }
    981   Value *CreateLShr(Value *LHS, uint64_t RHS, const Twine &Name = "",
    982                     bool isExact = false) {
    983     return CreateLShr(LHS, ConstantInt::get(LHS->getType(), RHS), Name,isExact);
    984   }
    985 
    986   Value *CreateAShr(Value *LHS, Value *RHS, const Twine &Name = "",
    987                     bool isExact = false) {
    988     if (Constant *LC = dyn_cast<Constant>(LHS))
    989       if (Constant *RC = dyn_cast<Constant>(RHS))
    990         return Insert(Folder.CreateAShr(LC, RC, isExact), Name);
    991     if (!isExact)
    992       return Insert(BinaryOperator::CreateAShr(LHS, RHS), Name);
    993     return Insert(BinaryOperator::CreateExactAShr(LHS, RHS), Name);
    994   }
    995   Value *CreateAShr(Value *LHS, const APInt &RHS, const Twine &Name = "",
    996                     bool isExact = false) {
    997     return CreateAShr(LHS, ConstantInt::get(LHS->getType(), RHS), Name,isExact);
    998   }
    999   Value *CreateAShr(Value *LHS, uint64_t RHS, const Twine &Name = "",
   1000                     bool isExact = false) {
   1001     return CreateAShr(LHS, ConstantInt::get(LHS->getType(), RHS), Name,isExact);
   1002   }
   1003 
   1004   Value *CreateAnd(Value *LHS, Value *RHS, const Twine &Name = "") {
   1005     if (Constant *RC = dyn_cast<Constant>(RHS)) {
   1006       if (isa<ConstantInt>(RC) && cast<ConstantInt>(RC)->isAllOnesValue())
   1007         return LHS;  // LHS & -1 -> LHS
   1008       if (Constant *LC = dyn_cast<Constant>(LHS))
   1009         return Insert(Folder.CreateAnd(LC, RC), Name);
   1010     }
   1011     return Insert(BinaryOperator::CreateAnd(LHS, RHS), Name);
   1012   }
   1013   Value *CreateAnd(Value *LHS, const APInt &RHS, const Twine &Name = "") {
   1014     return CreateAnd(LHS, ConstantInt::get(LHS->getType(), RHS), Name);
   1015   }
   1016   Value *CreateAnd(Value *LHS, uint64_t RHS, const Twine &Name = "") {
   1017     return CreateAnd(LHS, ConstantInt::get(LHS->getType(), RHS), Name);
   1018   }
   1019 
   1020   Value *CreateOr(Value *LHS, Value *RHS, const Twine &Name = "") {
   1021     if (Constant *RC = dyn_cast<Constant>(RHS)) {
   1022       if (RC->isNullValue())
   1023         return LHS;  // LHS | 0 -> LHS
   1024       if (Constant *LC = dyn_cast<Constant>(LHS))
   1025         return Insert(Folder.CreateOr(LC, RC), Name);
   1026     }
   1027     return Insert(BinaryOperator::CreateOr(LHS, RHS), Name);
   1028   }
   1029   Value *CreateOr(Value *LHS, const APInt &RHS, const Twine &Name = "") {
   1030     return CreateOr(LHS, ConstantInt::get(LHS->getType(), RHS), Name);
   1031   }
   1032   Value *CreateOr(Value *LHS, uint64_t RHS, const Twine &Name = "") {
   1033     return CreateOr(LHS, ConstantInt::get(LHS->getType(), RHS), Name);
   1034   }
   1035 
   1036   Value *CreateXor(Value *LHS, Value *RHS, const Twine &Name = "") {
   1037     if (Constant *LC = dyn_cast<Constant>(LHS))
   1038       if (Constant *RC = dyn_cast<Constant>(RHS))
   1039         return Insert(Folder.CreateXor(LC, RC), Name);
   1040     return Insert(BinaryOperator::CreateXor(LHS, RHS), Name);
   1041   }
   1042   Value *CreateXor(Value *LHS, const APInt &RHS, const Twine &Name = "") {
   1043     return CreateXor(LHS, ConstantInt::get(LHS->getType(), RHS), Name);
   1044   }
   1045   Value *CreateXor(Value *LHS, uint64_t RHS, const Twine &Name = "") {
   1046     return CreateXor(LHS, ConstantInt::get(LHS->getType(), RHS), Name);
   1047   }
   1048 
   1049   Value *CreateBinOp(Instruction::BinaryOps Opc,
   1050                      Value *LHS, Value *RHS, const Twine &Name = "",
   1051                      MDNode *FPMathTag = nullptr) {
   1052     if (Constant *LC = dyn_cast<Constant>(LHS))
   1053       if (Constant *RC = dyn_cast<Constant>(RHS))
   1054         return Insert(Folder.CreateBinOp(Opc, LC, RC), Name);
   1055     Instruction *BinOp = BinaryOperator::Create(Opc, LHS, RHS);
   1056     if (isa<FPMathOperator>(BinOp))
   1057       BinOp = AddFPMathAttributes(BinOp, FPMathTag, FMF);
   1058     return Insert(BinOp, Name);
   1059   }
   1060 
   1061   Value *CreateNeg(Value *V, const Twine &Name = "",
   1062                    bool HasNUW = false, bool HasNSW = false) {
   1063     if (Constant *VC = dyn_cast<Constant>(V))
   1064       return Insert(Folder.CreateNeg(VC, HasNUW, HasNSW), Name);
   1065     BinaryOperator *BO = Insert(BinaryOperator::CreateNeg(V), Name);
   1066     if (HasNUW) BO->setHasNoUnsignedWrap();
   1067     if (HasNSW) BO->setHasNoSignedWrap();
   1068     return BO;
   1069   }
   1070   Value *CreateNSWNeg(Value *V, const Twine &Name = "") {
   1071     return CreateNeg(V, Name, false, true);
   1072   }
   1073   Value *CreateNUWNeg(Value *V, const Twine &Name = "") {
   1074     return CreateNeg(V, Name, true, false);
   1075   }
   1076   Value *CreateFNeg(Value *V, const Twine &Name = "",
   1077                     MDNode *FPMathTag = nullptr) {
   1078     if (Constant *VC = dyn_cast<Constant>(V))
   1079       return Insert(Folder.CreateFNeg(VC), Name);
   1080     return Insert(AddFPMathAttributes(BinaryOperator::CreateFNeg(V),
   1081                                       FPMathTag, FMF), Name);
   1082   }
   1083   Value *CreateNot(Value *V, const Twine &Name = "") {
   1084     if (Constant *VC = dyn_cast<Constant>(V))
   1085       return Insert(Folder.CreateNot(VC), Name);
   1086     return Insert(BinaryOperator::CreateNot(V), Name);
   1087   }
   1088 
   1089   //===--------------------------------------------------------------------===//
   1090   // Instruction creation methods: Memory Instructions
   1091   //===--------------------------------------------------------------------===//
   1092 
   1093   AllocaInst *CreateAlloca(Type *Ty, unsigned AddrSpace,
   1094                            Value *ArraySize = nullptr, const Twine &Name = "") {
   1095     return Insert(new AllocaInst(Ty, AddrSpace, ArraySize), Name);
   1096   }
   1097 
   1098   AllocaInst *CreateAlloca(Type *Ty, Value *ArraySize = nullptr,
   1099                            const Twine &Name = "") {
   1100     const DataLayout &DL = BB->getParent()->getParent()->getDataLayout();
   1101     return Insert(new AllocaInst(Ty, DL.getAllocaAddrSpace(), ArraySize), Name);
   1102   }
   1103   // \brief Provided to resolve 'CreateLoad(Ptr, "...")' correctly, instead of
   1104   // converting the string to 'bool' for the isVolatile parameter.
   1105   LoadInst *CreateLoad(Value *Ptr, const char *Name) {
   1106     return Insert(new LoadInst(Ptr), Name);
   1107   }
   1108   LoadInst *CreateLoad(Value *Ptr, const Twine &Name = "") {
   1109     return Insert(new LoadInst(Ptr), Name);
   1110   }
   1111   LoadInst *CreateLoad(Type *Ty, Value *Ptr, const Twine &Name = "") {
   1112     return Insert(new LoadInst(Ty, Ptr), Name);
   1113   }
   1114   LoadInst *CreateLoad(Value *Ptr, bool isVolatile, const Twine &Name = "") {
   1115     return Insert(new LoadInst(Ptr, nullptr, isVolatile), Name);
   1116   }
   1117   StoreInst *CreateStore(Value *Val, Value *Ptr, bool isVolatile = false) {
   1118     return Insert(new StoreInst(Val, Ptr, isVolatile));
   1119   }
   1120   // \brief Provided to resolve 'CreateAlignedLoad(Ptr, Align, "...")'
   1121   // correctly, instead of converting the string to 'bool' for the isVolatile
   1122   // parameter.
   1123   LoadInst *CreateAlignedLoad(Value *Ptr, unsigned Align, const char *Name) {
   1124     LoadInst *LI = CreateLoad(Ptr, Name);
   1125     LI->setAlignment(Align);
   1126     return LI;
   1127   }
   1128   LoadInst *CreateAlignedLoad(Value *Ptr, unsigned Align,
   1129                               const Twine &Name = "") {
   1130     LoadInst *LI = CreateLoad(Ptr, Name);
   1131     LI->setAlignment(Align);
   1132     return LI;
   1133   }
   1134   LoadInst *CreateAlignedLoad(Value *Ptr, unsigned Align, bool isVolatile,
   1135                               const Twine &Name = "") {
   1136     LoadInst *LI = CreateLoad(Ptr, isVolatile, Name);
   1137     LI->setAlignment(Align);
   1138     return LI;
   1139   }
   1140   StoreInst *CreateAlignedStore(Value *Val, Value *Ptr, unsigned Align,
   1141                                 bool isVolatile = false) {
   1142     StoreInst *SI = CreateStore(Val, Ptr, isVolatile);
   1143     SI->setAlignment(Align);
   1144     return SI;
   1145   }
   1146   FenceInst *CreateFence(AtomicOrdering Ordering,
   1147                          SynchronizationScope SynchScope = CrossThread,
   1148                          const Twine &Name = "") {
   1149     return Insert(new FenceInst(Context, Ordering, SynchScope), Name);
   1150   }
   1151   AtomicCmpXchgInst *
   1152   CreateAtomicCmpXchg(Value *Ptr, Value *Cmp, Value *New,
   1153                       AtomicOrdering SuccessOrdering,
   1154                       AtomicOrdering FailureOrdering,
   1155                       SynchronizationScope SynchScope = CrossThread) {
   1156     return Insert(new AtomicCmpXchgInst(Ptr, Cmp, New, SuccessOrdering,
   1157                                         FailureOrdering, SynchScope));
   1158   }
   1159   AtomicRMWInst *CreateAtomicRMW(AtomicRMWInst::BinOp Op, Value *Ptr, Value *Val,
   1160                                  AtomicOrdering Ordering,
   1161                                SynchronizationScope SynchScope = CrossThread) {
   1162     return Insert(new AtomicRMWInst(Op, Ptr, Val, Ordering, SynchScope));
   1163   }
   1164   Value *CreateGEP(Value *Ptr, ArrayRef<Value *> IdxList,
   1165                    const Twine &Name = "") {
   1166     return CreateGEP(nullptr, Ptr, IdxList, Name);
   1167   }
   1168   Value *CreateGEP(Type *Ty, Value *Ptr, ArrayRef<Value *> IdxList,
   1169                    const Twine &Name = "") {
   1170     if (Constant *PC = dyn_cast<Constant>(Ptr)) {
   1171       // Every index must be constant.
   1172       size_t i, e;
   1173       for (i = 0, e = IdxList.size(); i != e; ++i)
   1174         if (!isa<Constant>(IdxList[i]))
   1175           break;
   1176       if (i == e)
   1177         return Insert(Folder.CreateGetElementPtr(Ty, PC, IdxList), Name);
   1178     }
   1179     return Insert(GetElementPtrInst::Create(Ty, Ptr, IdxList), Name);
   1180   }
   1181   Value *CreateInBoundsGEP(Value *Ptr, ArrayRef<Value *> IdxList,
   1182                            const Twine &Name = "") {
   1183     return CreateInBoundsGEP(nullptr, Ptr, IdxList, Name);
   1184   }
   1185   Value *CreateInBoundsGEP(Type *Ty, Value *Ptr, ArrayRef<Value *> IdxList,
   1186                            const Twine &Name = "") {
   1187     if (Constant *PC = dyn_cast<Constant>(Ptr)) {
   1188       // Every index must be constant.
   1189       size_t i, e;
   1190       for (i = 0, e = IdxList.size(); i != e; ++i)
   1191         if (!isa<Constant>(IdxList[i]))
   1192           break;
   1193       if (i == e)
   1194         return Insert(Folder.CreateInBoundsGetElementPtr(Ty, PC, IdxList),
   1195                       Name);
   1196     }
   1197     return Insert(GetElementPtrInst::CreateInBounds(Ty, Ptr, IdxList), Name);
   1198   }
   1199   Value *CreateGEP(Value *Ptr, Value *Idx, const Twine &Name = "") {
   1200     return CreateGEP(nullptr, Ptr, Idx, Name);
   1201   }
   1202   Value *CreateGEP(Type *Ty, Value *Ptr, Value *Idx, const Twine &Name = "") {
   1203     if (Constant *PC = dyn_cast<Constant>(Ptr))
   1204       if (Constant *IC = dyn_cast<Constant>(Idx))
   1205         return Insert(Folder.CreateGetElementPtr(Ty, PC, IC), Name);
   1206     return Insert(GetElementPtrInst::Create(Ty, Ptr, Idx), Name);
   1207   }
   1208   Value *CreateInBoundsGEP(Type *Ty, Value *Ptr, Value *Idx,
   1209                            const Twine &Name = "") {
   1210     if (Constant *PC = dyn_cast<Constant>(Ptr))
   1211       if (Constant *IC = dyn_cast<Constant>(Idx))
   1212         return Insert(Folder.CreateInBoundsGetElementPtr(Ty, PC, IC), Name);
   1213     return Insert(GetElementPtrInst::CreateInBounds(Ty, Ptr, Idx), Name);
   1214   }
   1215   Value *CreateConstGEP1_32(Value *Ptr, unsigned Idx0, const Twine &Name = "") {
   1216     return CreateConstGEP1_32(nullptr, Ptr, Idx0, Name);
   1217   }
   1218   Value *CreateConstGEP1_32(Type *Ty, Value *Ptr, unsigned Idx0,
   1219                             const Twine &Name = "") {
   1220     Value *Idx = ConstantInt::get(Type::getInt32Ty(Context), Idx0);
   1221 
   1222     if (Constant *PC = dyn_cast<Constant>(Ptr))
   1223       return Insert(Folder.CreateGetElementPtr(Ty, PC, Idx), Name);
   1224 
   1225     return Insert(GetElementPtrInst::Create(Ty, Ptr, Idx), Name);
   1226   }
   1227   Value *CreateConstInBoundsGEP1_32(Type *Ty, Value *Ptr, unsigned Idx0,
   1228                                     const Twine &Name = "") {
   1229     Value *Idx = ConstantInt::get(Type::getInt32Ty(Context), Idx0);
   1230 
   1231     if (Constant *PC = dyn_cast<Constant>(Ptr))
   1232       return Insert(Folder.CreateInBoundsGetElementPtr(Ty, PC, Idx), Name);
   1233 
   1234     return Insert(GetElementPtrInst::CreateInBounds(Ty, Ptr, Idx), Name);
   1235   }
   1236   Value *CreateConstGEP2_32(Type *Ty, Value *Ptr, unsigned Idx0, unsigned Idx1,
   1237                             const Twine &Name = "") {
   1238     Value *Idxs[] = {
   1239       ConstantInt::get(Type::getInt32Ty(Context), Idx0),
   1240       ConstantInt::get(Type::getInt32Ty(Context), Idx1)
   1241     };
   1242 
   1243     if (Constant *PC = dyn_cast<Constant>(Ptr))
   1244       return Insert(Folder.CreateGetElementPtr(Ty, PC, Idxs), Name);
   1245 
   1246     return Insert(GetElementPtrInst::Create(Ty, Ptr, Idxs), Name);
   1247   }
   1248   Value *CreateConstInBoundsGEP2_32(Type *Ty, Value *Ptr, unsigned Idx0,
   1249                                     unsigned Idx1, const Twine &Name = "") {
   1250     Value *Idxs[] = {
   1251       ConstantInt::get(Type::getInt32Ty(Context), Idx0),
   1252       ConstantInt::get(Type::getInt32Ty(Context), Idx1)
   1253     };
   1254 
   1255     if (Constant *PC = dyn_cast<Constant>(Ptr))
   1256       return Insert(Folder.CreateInBoundsGetElementPtr(Ty, PC, Idxs), Name);
   1257 
   1258     return Insert(GetElementPtrInst::CreateInBounds(Ty, Ptr, Idxs), Name);
   1259   }
   1260   Value *CreateConstGEP1_64(Value *Ptr, uint64_t Idx0, const Twine &Name = "") {
   1261     Value *Idx = ConstantInt::get(Type::getInt64Ty(Context), Idx0);
   1262 
   1263     if (Constant *PC = dyn_cast<Constant>(Ptr))
   1264       return Insert(Folder.CreateGetElementPtr(nullptr, PC, Idx), Name);
   1265 
   1266     return Insert(GetElementPtrInst::Create(nullptr, Ptr, Idx), Name);
   1267   }
   1268   Value *CreateConstInBoundsGEP1_64(Value *Ptr, uint64_t Idx0,
   1269                                     const Twine &Name = "") {
   1270     Value *Idx = ConstantInt::get(Type::getInt64Ty(Context), Idx0);
   1271 
   1272     if (Constant *PC = dyn_cast<Constant>(Ptr))
   1273       return Insert(Folder.CreateInBoundsGetElementPtr(nullptr, PC, Idx), Name);
   1274 
   1275     return Insert(GetElementPtrInst::CreateInBounds(nullptr, Ptr, Idx), Name);
   1276   }
   1277   Value *CreateConstGEP2_64(Value *Ptr, uint64_t Idx0, uint64_t Idx1,
   1278                     const Twine &Name = "") {
   1279     Value *Idxs[] = {
   1280       ConstantInt::get(Type::getInt64Ty(Context), Idx0),
   1281       ConstantInt::get(Type::getInt64Ty(Context), Idx1)
   1282     };
   1283 
   1284     if (Constant *PC = dyn_cast<Constant>(Ptr))
   1285       return Insert(Folder.CreateGetElementPtr(nullptr, PC, Idxs), Name);
   1286 
   1287     return Insert(GetElementPtrInst::Create(nullptr, Ptr, Idxs), Name);
   1288   }
   1289   Value *CreateConstInBoundsGEP2_64(Value *Ptr, uint64_t Idx0, uint64_t Idx1,
   1290                                     const Twine &Name = "") {
   1291     Value *Idxs[] = {
   1292       ConstantInt::get(Type::getInt64Ty(Context), Idx0),
   1293       ConstantInt::get(Type::getInt64Ty(Context), Idx1)
   1294     };
   1295 
   1296     if (Constant *PC = dyn_cast<Constant>(Ptr))
   1297       return Insert(Folder.CreateInBoundsGetElementPtr(nullptr, PC, Idxs),
   1298                     Name);
   1299 
   1300     return Insert(GetElementPtrInst::CreateInBounds(nullptr, Ptr, Idxs), Name);
   1301   }
   1302   Value *CreateStructGEP(Type *Ty, Value *Ptr, unsigned Idx,
   1303                          const Twine &Name = "") {
   1304     return CreateConstInBoundsGEP2_32(Ty, Ptr, 0, Idx, Name);
   1305   }
   1306 
   1307   /// \brief Same as CreateGlobalString, but return a pointer with "i8*" type
   1308   /// instead of a pointer to array of i8.
   1309   Value *CreateGlobalStringPtr(StringRef Str, const Twine &Name = "",
   1310                                unsigned AddressSpace = 0) {
   1311     GlobalVariable *gv = CreateGlobalString(Str, Name, AddressSpace);
   1312     Value *zero = ConstantInt::get(Type::getInt32Ty(Context), 0);
   1313     Value *Args[] = { zero, zero };
   1314     return CreateInBoundsGEP(gv->getValueType(), gv, Args, Name);
   1315   }
   1316 
   1317   //===--------------------------------------------------------------------===//
   1318   // Instruction creation methods: Cast/Conversion Operators
   1319   //===--------------------------------------------------------------------===//
   1320 
   1321   Value *CreateTrunc(Value *V, Type *DestTy, const Twine &Name = "") {
   1322     return CreateCast(Instruction::Trunc, V, DestTy, Name);
   1323   }
   1324   Value *CreateZExt(Value *V, Type *DestTy, const Twine &Name = "") {
   1325     return CreateCast(Instruction::ZExt, V, DestTy, Name);
   1326   }
   1327   Value *CreateSExt(Value *V, Type *DestTy, const Twine &Name = "") {
   1328     return CreateCast(Instruction::SExt, V, DestTy, Name);
   1329   }
   1330   /// \brief Create a ZExt or Trunc from the integer value V to DestTy. Return
   1331   /// the value untouched if the type of V is already DestTy.
   1332   Value *CreateZExtOrTrunc(Value *V, Type *DestTy,
   1333                            const Twine &Name = "") {
   1334     assert(V->getType()->isIntOrIntVectorTy() &&
   1335            DestTy->isIntOrIntVectorTy() &&
   1336            "Can only zero extend/truncate integers!");
   1337     Type *VTy = V->getType();
   1338     if (VTy->getScalarSizeInBits() < DestTy->getScalarSizeInBits())
   1339       return CreateZExt(V, DestTy, Name);
   1340     if (VTy->getScalarSizeInBits() > DestTy->getScalarSizeInBits())
   1341       return CreateTrunc(V, DestTy, Name);
   1342     return V;
   1343   }
   1344   /// \brief Create a SExt or Trunc from the integer value V to DestTy. Return
   1345   /// the value untouched if the type of V is already DestTy.
   1346   Value *CreateSExtOrTrunc(Value *V, Type *DestTy,
   1347                            const Twine &Name = "") {
   1348     assert(V->getType()->isIntOrIntVectorTy() &&
   1349            DestTy->isIntOrIntVectorTy() &&
   1350            "Can only sign extend/truncate integers!");
   1351     Type *VTy = V->getType();
   1352     if (VTy->getScalarSizeInBits() < DestTy->getScalarSizeInBits())
   1353       return CreateSExt(V, DestTy, Name);
   1354     if (VTy->getScalarSizeInBits() > DestTy->getScalarSizeInBits())
   1355       return CreateTrunc(V, DestTy, Name);
   1356     return V;
   1357   }
   1358   Value *CreateFPToUI(Value *V, Type *DestTy, const Twine &Name = ""){
   1359     return CreateCast(Instruction::FPToUI, V, DestTy, Name);
   1360   }
   1361   Value *CreateFPToSI(Value *V, Type *DestTy, const Twine &Name = ""){
   1362     return CreateCast(Instruction::FPToSI, V, DestTy, Name);
   1363   }
   1364   Value *CreateUIToFP(Value *V, Type *DestTy, const Twine &Name = ""){
   1365     return CreateCast(Instruction::UIToFP, V, DestTy, Name);
   1366   }
   1367   Value *CreateSIToFP(Value *V, Type *DestTy, const Twine &Name = ""){
   1368     return CreateCast(Instruction::SIToFP, V, DestTy, Name);
   1369   }
   1370   Value *CreateFPTrunc(Value *V, Type *DestTy,
   1371                        const Twine &Name = "") {
   1372     return CreateCast(Instruction::FPTrunc, V, DestTy, Name);
   1373   }
   1374   Value *CreateFPExt(Value *V, Type *DestTy, const Twine &Name = "") {
   1375     return CreateCast(Instruction::FPExt, V, DestTy, Name);
   1376   }
   1377   Value *CreatePtrToInt(Value *V, Type *DestTy,
   1378                         const Twine &Name = "") {
   1379     return CreateCast(Instruction::PtrToInt, V, DestTy, Name);
   1380   }
   1381   Value *CreateIntToPtr(Value *V, Type *DestTy,
   1382                         const Twine &Name = "") {
   1383     return CreateCast(Instruction::IntToPtr, V, DestTy, Name);
   1384   }
   1385   Value *CreateBitCast(Value *V, Type *DestTy,
   1386                        const Twine &Name = "") {
   1387     return CreateCast(Instruction::BitCast, V, DestTy, Name);
   1388   }
   1389   Value *CreateAddrSpaceCast(Value *V, Type *DestTy,
   1390                              const Twine &Name = "") {
   1391     return CreateCast(Instruction::AddrSpaceCast, V, DestTy, Name);
   1392   }
   1393   Value *CreateZExtOrBitCast(Value *V, Type *DestTy,
   1394                              const Twine &Name = "") {
   1395     if (V->getType() == DestTy)
   1396       return V;
   1397     if (Constant *VC = dyn_cast<Constant>(V))
   1398       return Insert(Folder.CreateZExtOrBitCast(VC, DestTy), Name);
   1399     return Insert(CastInst::CreateZExtOrBitCast(V, DestTy), Name);
   1400   }
   1401   Value *CreateSExtOrBitCast(Value *V, Type *DestTy,
   1402                              const Twine &Name = "") {
   1403     if (V->getType() == DestTy)
   1404       return V;
   1405     if (Constant *VC = dyn_cast<Constant>(V))
   1406       return Insert(Folder.CreateSExtOrBitCast(VC, DestTy), Name);
   1407     return Insert(CastInst::CreateSExtOrBitCast(V, DestTy), Name);
   1408   }
   1409   Value *CreateTruncOrBitCast(Value *V, Type *DestTy,
   1410                               const Twine &Name = "") {
   1411     if (V->getType() == DestTy)
   1412       return V;
   1413     if (Constant *VC = dyn_cast<Constant>(V))
   1414       return Insert(Folder.CreateTruncOrBitCast(VC, DestTy), Name);
   1415     return Insert(CastInst::CreateTruncOrBitCast(V, DestTy), Name);
   1416   }
   1417   Value *CreateCast(Instruction::CastOps Op, Value *V, Type *DestTy,
   1418                     const Twine &Name = "") {
   1419     if (V->getType() == DestTy)
   1420       return V;
   1421     if (Constant *VC = dyn_cast<Constant>(V))
   1422       return Insert(Folder.CreateCast(Op, VC, DestTy), Name);
   1423     return Insert(CastInst::Create(Op, V, DestTy), Name);
   1424   }
   1425   Value *CreatePointerCast(Value *V, Type *DestTy,
   1426                            const Twine &Name = "") {
   1427     if (V->getType() == DestTy)
   1428       return V;
   1429     if (Constant *VC = dyn_cast<Constant>(V))
   1430       return Insert(Folder.CreatePointerCast(VC, DestTy), Name);
   1431     return Insert(CastInst::CreatePointerCast(V, DestTy), Name);
   1432   }
   1433 
   1434   Value *CreatePointerBitCastOrAddrSpaceCast(Value *V, Type *DestTy,
   1435                                              const Twine &Name = "") {
   1436     if (V->getType() == DestTy)
   1437       return V;
   1438 
   1439     if (Constant *VC = dyn_cast<Constant>(V)) {
   1440       return Insert(Folder.CreatePointerBitCastOrAddrSpaceCast(VC, DestTy),
   1441                     Name);
   1442     }
   1443 
   1444     return Insert(CastInst::CreatePointerBitCastOrAddrSpaceCast(V, DestTy),
   1445                   Name);
   1446   }
   1447 
   1448   Value *CreateIntCast(Value *V, Type *DestTy, bool isSigned,
   1449                        const Twine &Name = "") {
   1450     if (V->getType() == DestTy)
   1451       return V;
   1452     if (Constant *VC = dyn_cast<Constant>(V))
   1453       return Insert(Folder.CreateIntCast(VC, DestTy, isSigned), Name);
   1454     return Insert(CastInst::CreateIntegerCast(V, DestTy, isSigned), Name);
   1455   }
   1456 
   1457   Value *CreateBitOrPointerCast(Value *V, Type *DestTy,
   1458                                 const Twine &Name = "") {
   1459     if (V->getType() == DestTy)
   1460       return V;
   1461     if (V->getType()->getScalarType()->isPointerTy() &&
   1462         DestTy->getScalarType()->isIntegerTy())
   1463       return CreatePtrToInt(V, DestTy, Name);
   1464     if (V->getType()->getScalarType()->isIntegerTy() &&
   1465         DestTy->getScalarType()->isPointerTy())
   1466       return CreateIntToPtr(V, DestTy, Name);
   1467 
   1468     return CreateBitCast(V, DestTy, Name);
   1469   }
   1470 
   1471 public:
   1472   Value *CreateFPCast(Value *V, Type *DestTy, const Twine &Name = "") {
   1473     if (V->getType() == DestTy)
   1474       return V;
   1475     if (Constant *VC = dyn_cast<Constant>(V))
   1476       return Insert(Folder.CreateFPCast(VC, DestTy), Name);
   1477     return Insert(CastInst::CreateFPCast(V, DestTy), Name);
   1478   }
   1479 
   1480   // \brief Provided to resolve 'CreateIntCast(Ptr, Ptr, "...")', giving a
   1481   // compile time error, instead of converting the string to bool for the
   1482   // isSigned parameter.
   1483   Value *CreateIntCast(Value *, Type *, const char *) = delete;
   1484 
   1485   //===--------------------------------------------------------------------===//
   1486   // Instruction creation methods: Compare Instructions
   1487   //===--------------------------------------------------------------------===//
   1488 
   1489   Value *CreateICmpEQ(Value *LHS, Value *RHS, const Twine &Name = "") {
   1490     return CreateICmp(ICmpInst::ICMP_EQ, LHS, RHS, Name);
   1491   }
   1492   Value *CreateICmpNE(Value *LHS, Value *RHS, const Twine &Name = "") {
   1493     return CreateICmp(ICmpInst::ICMP_NE, LHS, RHS, Name);
   1494   }
   1495   Value *CreateICmpUGT(Value *LHS, Value *RHS, const Twine &Name = "") {
   1496     return CreateICmp(ICmpInst::ICMP_UGT, LHS, RHS, Name);
   1497   }
   1498   Value *CreateICmpUGE(Value *LHS, Value *RHS, const Twine &Name = "") {
   1499     return CreateICmp(ICmpInst::ICMP_UGE, LHS, RHS, Name);
   1500   }
   1501   Value *CreateICmpULT(Value *LHS, Value *RHS, const Twine &Name = "") {
   1502     return CreateICmp(ICmpInst::ICMP_ULT, LHS, RHS, Name);
   1503   }
   1504   Value *CreateICmpULE(Value *LHS, Value *RHS, const Twine &Name = "") {
   1505     return CreateICmp(ICmpInst::ICMP_ULE, LHS, RHS, Name);
   1506   }
   1507   Value *CreateICmpSGT(Value *LHS, Value *RHS, const Twine &Name = "") {
   1508     return CreateICmp(ICmpInst::ICMP_SGT, LHS, RHS, Name);
   1509   }
   1510   Value *CreateICmpSGE(Value *LHS, Value *RHS, const Twine &Name = "") {
   1511     return CreateICmp(ICmpInst::ICMP_SGE, LHS, RHS, Name);
   1512   }
   1513   Value *CreateICmpSLT(Value *LHS, Value *RHS, const Twine &Name = "") {
   1514     return CreateICmp(ICmpInst::ICMP_SLT, LHS, RHS, Name);
   1515   }
   1516   Value *CreateICmpSLE(Value *LHS, Value *RHS, const Twine &Name = "") {
   1517     return CreateICmp(ICmpInst::ICMP_SLE, LHS, RHS, Name);
   1518   }
   1519 
   1520   Value *CreateFCmpOEQ(Value *LHS, Value *RHS, const Twine &Name = "",
   1521                        MDNode *FPMathTag = nullptr) {
   1522     return CreateFCmp(FCmpInst::FCMP_OEQ, LHS, RHS, Name, FPMathTag);
   1523   }
   1524   Value *CreateFCmpOGT(Value *LHS, Value *RHS, const Twine &Name = "",
   1525                        MDNode *FPMathTag = nullptr) {
   1526     return CreateFCmp(FCmpInst::FCMP_OGT, LHS, RHS, Name, FPMathTag);
   1527   }
   1528   Value *CreateFCmpOGE(Value *LHS, Value *RHS, const Twine &Name = "",
   1529                        MDNode *FPMathTag = nullptr) {
   1530     return CreateFCmp(FCmpInst::FCMP_OGE, LHS, RHS, Name, FPMathTag);
   1531   }
   1532   Value *CreateFCmpOLT(Value *LHS, Value *RHS, const Twine &Name = "",
   1533                        MDNode *FPMathTag = nullptr) {
   1534     return CreateFCmp(FCmpInst::FCMP_OLT, LHS, RHS, Name, FPMathTag);
   1535   }
   1536   Value *CreateFCmpOLE(Value *LHS, Value *RHS, const Twine &Name = "",
   1537                        MDNode *FPMathTag = nullptr) {
   1538     return CreateFCmp(FCmpInst::FCMP_OLE, LHS, RHS, Name, FPMathTag);
   1539   }
   1540   Value *CreateFCmpONE(Value *LHS, Value *RHS, const Twine &Name = "",
   1541                        MDNode *FPMathTag = nullptr) {
   1542     return CreateFCmp(FCmpInst::FCMP_ONE, LHS, RHS, Name, FPMathTag);
   1543   }
   1544   Value *CreateFCmpORD(Value *LHS, Value *RHS, const Twine &Name = "",
   1545                        MDNode *FPMathTag = nullptr) {
   1546     return CreateFCmp(FCmpInst::FCMP_ORD, LHS, RHS, Name, FPMathTag);
   1547   }
   1548   Value *CreateFCmpUNO(Value *LHS, Value *RHS, const Twine &Name = "",
   1549                        MDNode *FPMathTag = nullptr) {
   1550     return CreateFCmp(FCmpInst::FCMP_UNO, LHS, RHS, Name, FPMathTag);
   1551   }
   1552   Value *CreateFCmpUEQ(Value *LHS, Value *RHS, const Twine &Name = "",
   1553                        MDNode *FPMathTag = nullptr) {
   1554     return CreateFCmp(FCmpInst::FCMP_UEQ, LHS, RHS, Name, FPMathTag);
   1555   }
   1556   Value *CreateFCmpUGT(Value *LHS, Value *RHS, const Twine &Name = "",
   1557                        MDNode *FPMathTag = nullptr) {
   1558     return CreateFCmp(FCmpInst::FCMP_UGT, LHS, RHS, Name, FPMathTag);
   1559   }
   1560   Value *CreateFCmpUGE(Value *LHS, Value *RHS, const Twine &Name = "",
   1561                        MDNode *FPMathTag = nullptr) {
   1562     return CreateFCmp(FCmpInst::FCMP_UGE, LHS, RHS, Name, FPMathTag);
   1563   }
   1564   Value *CreateFCmpULT(Value *LHS, Value *RHS, const Twine &Name = "",
   1565                        MDNode *FPMathTag = nullptr) {
   1566     return CreateFCmp(FCmpInst::FCMP_ULT, LHS, RHS, Name, FPMathTag);
   1567   }
   1568   Value *CreateFCmpULE(Value *LHS, Value *RHS, const Twine &Name = "",
   1569                        MDNode *FPMathTag = nullptr) {
   1570     return CreateFCmp(FCmpInst::FCMP_ULE, LHS, RHS, Name, FPMathTag);
   1571   }
   1572   Value *CreateFCmpUNE(Value *LHS, Value *RHS, const Twine &Name = "",
   1573                        MDNode *FPMathTag = nullptr) {
   1574     return CreateFCmp(FCmpInst::FCMP_UNE, LHS, RHS, Name, FPMathTag);
   1575   }
   1576 
   1577   Value *CreateICmp(CmpInst::Predicate P, Value *LHS, Value *RHS,
   1578                     const Twine &Name = "") {
   1579     if (Constant *LC = dyn_cast<Constant>(LHS))
   1580       if (Constant *RC = dyn_cast<Constant>(RHS))
   1581         return Insert(Folder.CreateICmp(P, LC, RC), Name);
   1582     return Insert(new ICmpInst(P, LHS, RHS), Name);
   1583   }
   1584   Value *CreateFCmp(CmpInst::Predicate P, Value *LHS, Value *RHS,
   1585                     const Twine &Name = "", MDNode *FPMathTag = nullptr) {
   1586     if (Constant *LC = dyn_cast<Constant>(LHS))
   1587       if (Constant *RC = dyn_cast<Constant>(RHS))
   1588         return Insert(Folder.CreateFCmp(P, LC, RC), Name);
   1589     return Insert(AddFPMathAttributes(new FCmpInst(P, LHS, RHS),
   1590                                       FPMathTag, FMF), Name);
   1591   }
   1592 
   1593   //===--------------------------------------------------------------------===//
   1594   // Instruction creation methods: Other Instructions
   1595   //===--------------------------------------------------------------------===//
   1596 
   1597   PHINode *CreatePHI(Type *Ty, unsigned NumReservedValues,
   1598                      const Twine &Name = "") {
   1599     return Insert(PHINode::Create(Ty, NumReservedValues), Name);
   1600   }
   1601 
   1602   CallInst *CreateCall(Value *Callee, ArrayRef<Value *> Args = None,
   1603                        const Twine &Name = "", MDNode *FPMathTag = nullptr) {
   1604     PointerType *PTy = cast<PointerType>(Callee->getType());
   1605     FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
   1606     return CreateCall(FTy, Callee, Args, Name, FPMathTag);
   1607   }
   1608 
   1609   CallInst *CreateCall(FunctionType *FTy, Value *Callee,
   1610                        ArrayRef<Value *> Args, const Twine &Name = "",
   1611                        MDNode *FPMathTag = nullptr) {
   1612     CallInst *CI = CallInst::Create(FTy, Callee, Args, DefaultOperandBundles);
   1613     if (isa<FPMathOperator>(CI))
   1614       CI = cast<CallInst>(AddFPMathAttributes(CI, FPMathTag, FMF));
   1615     return Insert(CI, Name);
   1616   }
   1617 
   1618   CallInst *CreateCall(Value *Callee, ArrayRef<Value *> Args,
   1619                        ArrayRef<OperandBundleDef> OpBundles,
   1620                        const Twine &Name = "", MDNode *FPMathTag = nullptr) {
   1621     CallInst *CI = CallInst::Create(Callee, Args, OpBundles);
   1622     if (isa<FPMathOperator>(CI))
   1623       CI = cast<CallInst>(AddFPMathAttributes(CI, FPMathTag, FMF));
   1624     return Insert(CI, Name);
   1625   }
   1626 
   1627   CallInst *CreateCall(Function *Callee, ArrayRef<Value *> Args,
   1628                        const Twine &Name = "", MDNode *FPMathTag = nullptr) {
   1629     return CreateCall(Callee->getFunctionType(), Callee, Args, Name, FPMathTag);
   1630   }
   1631 
   1632   Value *CreateSelect(Value *C, Value *True, Value *False,
   1633                       const Twine &Name = "", Instruction *MDFrom = nullptr) {
   1634     if (Constant *CC = dyn_cast<Constant>(C))
   1635       if (Constant *TC = dyn_cast<Constant>(True))
   1636         if (Constant *FC = dyn_cast<Constant>(False))
   1637           return Insert(Folder.CreateSelect(CC, TC, FC), Name);
   1638 
   1639     SelectInst *Sel = SelectInst::Create(C, True, False);
   1640     if (MDFrom) {
   1641       MDNode *Prof = MDFrom->getMetadata(LLVMContext::MD_prof);
   1642       MDNode *Unpred = MDFrom->getMetadata(LLVMContext::MD_unpredictable);
   1643       Sel = addBranchMetadata(Sel, Prof, Unpred);
   1644     }
   1645     return Insert(Sel, Name);
   1646   }
   1647 
   1648   VAArgInst *CreateVAArg(Value *List, Type *Ty, const Twine &Name = "") {
   1649     return Insert(new VAArgInst(List, Ty), Name);
   1650   }
   1651 
   1652   Value *CreateExtractElement(Value *Vec, Value *Idx,
   1653                               const Twine &Name = "") {
   1654     if (Constant *VC = dyn_cast<Constant>(Vec))
   1655       if (Constant *IC = dyn_cast<Constant>(Idx))
   1656         return Insert(Folder.CreateExtractElement(VC, IC), Name);
   1657     return Insert(ExtractElementInst::Create(Vec, Idx), Name);
   1658   }
   1659 
   1660   Value *CreateExtractElement(Value *Vec, uint64_t Idx,
   1661                               const Twine &Name = "") {
   1662     return CreateExtractElement(Vec, getInt64(Idx), Name);
   1663   }
   1664 
   1665   Value *CreateInsertElement(Value *Vec, Value *NewElt, Value *Idx,
   1666                              const Twine &Name = "") {
   1667     if (Constant *VC = dyn_cast<Constant>(Vec))
   1668       if (Constant *NC = dyn_cast<Constant>(NewElt))
   1669         if (Constant *IC = dyn_cast<Constant>(Idx))
   1670           return Insert(Folder.CreateInsertElement(VC, NC, IC), Name);
   1671     return Insert(InsertElementInst::Create(Vec, NewElt, Idx), Name);
   1672   }
   1673 
   1674   Value *CreateInsertElement(Value *Vec, Value *NewElt, uint64_t Idx,
   1675                              const Twine &Name = "") {
   1676     return CreateInsertElement(Vec, NewElt, getInt64(Idx), Name);
   1677   }
   1678 
   1679   Value *CreateShuffleVector(Value *V1, Value *V2, Value *Mask,
   1680                              const Twine &Name = "") {
   1681     if (Constant *V1C = dyn_cast<Constant>(V1))
   1682       if (Constant *V2C = dyn_cast<Constant>(V2))
   1683         if (Constant *MC = dyn_cast<Constant>(Mask))
   1684           return Insert(Folder.CreateShuffleVector(V1C, V2C, MC), Name);
   1685     return Insert(new ShuffleVectorInst(V1, V2, Mask), Name);
   1686   }
   1687 
   1688   Value *CreateShuffleVector(Value *V1, Value *V2, ArrayRef<uint32_t> IntMask,
   1689                              const Twine &Name = "") {
   1690     Value *Mask = ConstantDataVector::get(Context, IntMask);
   1691     return CreateShuffleVector(V1, V2, Mask, Name);
   1692   }
   1693 
   1694   Value *CreateExtractValue(Value *Agg,
   1695                             ArrayRef<unsigned> Idxs,
   1696                             const Twine &Name = "") {
   1697     if (Constant *AggC = dyn_cast<Constant>(Agg))
   1698       return Insert(Folder.CreateExtractValue(AggC, Idxs), Name);
   1699     return Insert(ExtractValueInst::Create(Agg, Idxs), Name);
   1700   }
   1701 
   1702   Value *CreateInsertValue(Value *Agg, Value *Val,
   1703                            ArrayRef<unsigned> Idxs,
   1704                            const Twine &Name = "") {
   1705     if (Constant *AggC = dyn_cast<Constant>(Agg))
   1706       if (Constant *ValC = dyn_cast<Constant>(Val))
   1707         return Insert(Folder.CreateInsertValue(AggC, ValC, Idxs), Name);
   1708     return Insert(InsertValueInst::Create(Agg, Val, Idxs), Name);
   1709   }
   1710 
   1711   LandingPadInst *CreateLandingPad(Type *Ty, unsigned NumClauses,
   1712                                    const Twine &Name = "") {
   1713     return Insert(LandingPadInst::Create(Ty, NumClauses), Name);
   1714   }
   1715 
   1716   //===--------------------------------------------------------------------===//
   1717   // Utility creation methods
   1718   //===--------------------------------------------------------------------===//
   1719 
   1720   /// \brief Return an i1 value testing if \p Arg is null.
   1721   Value *CreateIsNull(Value *Arg, const Twine &Name = "") {
   1722     return CreateICmpEQ(Arg, Constant::getNullValue(Arg->getType()),
   1723                         Name);
   1724   }
   1725 
   1726   /// \brief Return an i1 value testing if \p Arg is not null.
   1727   Value *CreateIsNotNull(Value *Arg, const Twine &Name = "") {
   1728     return CreateICmpNE(Arg, Constant::getNullValue(Arg->getType()),
   1729                         Name);
   1730   }
   1731 
   1732   /// \brief Return the i64 difference between two pointer values, dividing out
   1733   /// the size of the pointed-to objects.
   1734   ///
   1735   /// This is intended to implement C-style pointer subtraction. As such, the
   1736   /// pointers must be appropriately aligned for their element types and
   1737   /// pointing into the same object.
   1738   Value *CreatePtrDiff(Value *LHS, Value *RHS, const Twine &Name = "") {
   1739     assert(LHS->getType() == RHS->getType() &&
   1740            "Pointer subtraction operand types must match!");
   1741     PointerType *ArgType = cast<PointerType>(LHS->getType());
   1742     Value *LHS_int = CreatePtrToInt(LHS, Type::getInt64Ty(Context));
   1743     Value *RHS_int = CreatePtrToInt(RHS, Type::getInt64Ty(Context));
   1744     Value *Difference = CreateSub(LHS_int, RHS_int);
   1745     return CreateExactSDiv(Difference,
   1746                            ConstantExpr::getSizeOf(ArgType->getElementType()),
   1747                            Name);
   1748   }
   1749 
   1750   /// \brief Create an invariant.group.barrier intrinsic call, that stops
   1751   /// optimizer to propagate equality using invariant.group metadata.
   1752   /// If Ptr type is different from i8*, it's casted to i8* before call
   1753   /// and casted back to Ptr type after call.
   1754   Value *CreateInvariantGroupBarrier(Value *Ptr) {
   1755     Module *M = BB->getParent()->getParent();
   1756     Function *FnInvariantGroupBarrier = Intrinsic::getDeclaration(M,
   1757             Intrinsic::invariant_group_barrier);
   1758 
   1759     Type *ArgumentAndReturnType = FnInvariantGroupBarrier->getReturnType();
   1760     assert(ArgumentAndReturnType ==
   1761         FnInvariantGroupBarrier->getFunctionType()->getParamType(0) &&
   1762         "InvariantGroupBarrier should take and return the same type");
   1763     Type *PtrType = Ptr->getType();
   1764 
   1765     bool PtrTypeConversionNeeded = PtrType != ArgumentAndReturnType;
   1766     if (PtrTypeConversionNeeded)
   1767       Ptr = CreateBitCast(Ptr, ArgumentAndReturnType);
   1768 
   1769     CallInst *Fn = CreateCall(FnInvariantGroupBarrier, {Ptr});
   1770 
   1771     if (PtrTypeConversionNeeded)
   1772       return CreateBitCast(Fn, PtrType);
   1773     return Fn;
   1774   }
   1775 
   1776   /// \brief Return a vector value that contains \arg V broadcasted to \p
   1777   /// NumElts elements.
   1778   Value *CreateVectorSplat(unsigned NumElts, Value *V, const Twine &Name = "") {
   1779     assert(NumElts > 0 && "Cannot splat to an empty vector!");
   1780 
   1781     // First insert it into an undef vector so we can shuffle it.
   1782     Type *I32Ty = getInt32Ty();
   1783     Value *Undef = UndefValue::get(VectorType::get(V->getType(), NumElts));
   1784     V = CreateInsertElement(Undef, V, ConstantInt::get(I32Ty, 0),
   1785                             Name + ".splatinsert");
   1786 
   1787     // Shuffle the value across the desired number of elements.
   1788     Value *Zeros = ConstantAggregateZero::get(VectorType::get(I32Ty, NumElts));
   1789     return CreateShuffleVector(V, Undef, Zeros, Name + ".splat");
   1790   }
   1791 
   1792   /// \brief Return a value that has been extracted from a larger integer type.
   1793   Value *CreateExtractInteger(const DataLayout &DL, Value *From,
   1794                               IntegerType *ExtractedTy, uint64_t Offset,
   1795                               const Twine &Name) {
   1796     IntegerType *IntTy = cast<IntegerType>(From->getType());
   1797     assert(DL.getTypeStoreSize(ExtractedTy) + Offset <=
   1798                DL.getTypeStoreSize(IntTy) &&
   1799            "Element extends past full value");
   1800     uint64_t ShAmt = 8 * Offset;
   1801     Value *V = From;
   1802     if (DL.isBigEndian())
   1803       ShAmt = 8 * (DL.getTypeStoreSize(IntTy) -
   1804                    DL.getTypeStoreSize(ExtractedTy) - Offset);
   1805     if (ShAmt) {
   1806       V = CreateLShr(V, ShAmt, Name + ".shift");
   1807     }
   1808     assert(ExtractedTy->getBitWidth() <= IntTy->getBitWidth() &&
   1809            "Cannot extract to a larger integer!");
   1810     if (ExtractedTy != IntTy) {
   1811       V = CreateTrunc(V, ExtractedTy, Name + ".trunc");
   1812     }
   1813     return V;
   1814   }
   1815 
   1816 private:
   1817   /// \brief Helper function that creates an assume intrinsic call that
   1818   /// represents an alignment assumption on the provided Ptr, Mask, Type
   1819   /// and Offset.
   1820   CallInst *CreateAlignmentAssumptionHelper(const DataLayout &DL,
   1821                                             Value *PtrValue, Value *Mask,
   1822                                             Type *IntPtrTy,
   1823                                             Value *OffsetValue) {
   1824     Value *PtrIntValue = CreatePtrToInt(PtrValue, IntPtrTy, "ptrint");
   1825 
   1826     if (OffsetValue) {
   1827       bool IsOffsetZero = false;
   1828       if (ConstantInt *CI = dyn_cast<ConstantInt>(OffsetValue))
   1829         IsOffsetZero = CI->isZero();
   1830 
   1831       if (!IsOffsetZero) {
   1832         if (OffsetValue->getType() != IntPtrTy)
   1833           OffsetValue = CreateIntCast(OffsetValue, IntPtrTy, /*isSigned*/ true,
   1834                                       "offsetcast");
   1835         PtrIntValue = CreateSub(PtrIntValue, OffsetValue, "offsetptr");
   1836       }
   1837     }
   1838 
   1839     Value *Zero = ConstantInt::get(IntPtrTy, 0);
   1840     Value *MaskedPtr = CreateAnd(PtrIntValue, Mask, "maskedptr");
   1841     Value *InvCond = CreateICmpEQ(MaskedPtr, Zero, "maskcond");
   1842     return CreateAssumption(InvCond);
   1843   }
   1844 
   1845 public:
   1846   /// \brief Create an assume intrinsic call that represents an alignment
   1847   /// assumption on the provided pointer.
   1848   ///
   1849   /// An optional offset can be provided, and if it is provided, the offset
   1850   /// must be subtracted from the provided pointer to get the pointer with the
   1851   /// specified alignment.
   1852   CallInst *CreateAlignmentAssumption(const DataLayout &DL, Value *PtrValue,
   1853                                       unsigned Alignment,
   1854                                       Value *OffsetValue = nullptr) {
   1855     assert(isa<PointerType>(PtrValue->getType()) &&
   1856            "trying to create an alignment assumption on a non-pointer?");
   1857     PointerType *PtrTy = cast<PointerType>(PtrValue->getType());
   1858     Type *IntPtrTy = getIntPtrTy(DL, PtrTy->getAddressSpace());
   1859 
   1860     Value *Mask = ConstantInt::get(IntPtrTy, Alignment > 0 ? Alignment - 1 : 0);
   1861     return CreateAlignmentAssumptionHelper(DL, PtrValue, Mask, IntPtrTy,
   1862                                            OffsetValue);
   1863   }
   1864   //
   1865   /// \brief Create an assume intrinsic call that represents an alignment
   1866   /// assumption on the provided pointer.
   1867   ///
   1868   /// An optional offset can be provided, and if it is provided, the offset
   1869   /// must be subtracted from the provided pointer to get the pointer with the
   1870   /// specified alignment.
   1871   ///
   1872   /// This overload handles the condition where the Alignment is dependent
   1873   /// on an existing value rather than a static value.
   1874   CallInst *CreateAlignmentAssumption(const DataLayout &DL, Value *PtrValue,
   1875                                       Value *Alignment,
   1876                                       Value *OffsetValue = nullptr) {
   1877     assert(isa<PointerType>(PtrValue->getType()) &&
   1878            "trying to create an alignment assumption on a non-pointer?");
   1879     PointerType *PtrTy = cast<PointerType>(PtrValue->getType());
   1880     Type *IntPtrTy = getIntPtrTy(DL, PtrTy->getAddressSpace());
   1881 
   1882     if (Alignment->getType() != IntPtrTy)
   1883       Alignment = CreateIntCast(Alignment, IntPtrTy, /*isSigned*/ true,
   1884                                 "alignmentcast");
   1885     Value *IsPositive =
   1886         CreateICmp(CmpInst::ICMP_SGT, Alignment,
   1887                    ConstantInt::get(Alignment->getType(), 0), "ispositive");
   1888     Value *PositiveMask =
   1889         CreateSub(Alignment, ConstantInt::get(IntPtrTy, 1), "positivemask");
   1890     Value *Mask = CreateSelect(IsPositive, PositiveMask,
   1891                                ConstantInt::get(IntPtrTy, 0), "mask");
   1892 
   1893     return CreateAlignmentAssumptionHelper(DL, PtrValue, Mask, IntPtrTy,
   1894                                            OffsetValue);
   1895   }
   1896 };
   1897 
   1898 // Create wrappers for C Binding types (see CBindingWrapping.h).
   1899 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(IRBuilder<>, LLVMBuilderRef)
   1900 
   1901 } // end namespace llvm
   1902 
   1903 #endif // LLVM_IR_IRBUILDER_H
   1904