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      1 //===-- Instructions.cpp - Implement the LLVM instructions ----------------===//
      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 implements all of the non-inline methods for the LLVM instruction
     11 // classes.
     12 //
     13 //===----------------------------------------------------------------------===//
     14 
     15 #include "llvm/IR/Instructions.h"
     16 #include "LLVMContextImpl.h"
     17 #include "llvm/IR/CallSite.h"
     18 #include "llvm/IR/ConstantRange.h"
     19 #include "llvm/IR/Constants.h"
     20 #include "llvm/IR/DataLayout.h"
     21 #include "llvm/IR/DerivedTypes.h"
     22 #include "llvm/IR/Function.h"
     23 #include "llvm/IR/Module.h"
     24 #include "llvm/IR/Operator.h"
     25 #include "llvm/Support/ErrorHandling.h"
     26 #include "llvm/Support/MathExtras.h"
     27 using namespace llvm;
     28 
     29 //===----------------------------------------------------------------------===//
     30 //                            CallSite Class
     31 //===----------------------------------------------------------------------===//
     32 
     33 User::op_iterator CallSite::getCallee() const {
     34   Instruction *II(getInstruction());
     35   return isCall()
     36     ? cast<CallInst>(II)->op_end() - 1 // Skip Callee
     37     : cast<InvokeInst>(II)->op_end() - 3; // Skip BB, BB, Callee
     38 }
     39 
     40 //===----------------------------------------------------------------------===//
     41 //                            TerminatorInst Class
     42 //===----------------------------------------------------------------------===//
     43 
     44 // Out of line virtual method, so the vtable, etc has a home.
     45 TerminatorInst::~TerminatorInst() {
     46 }
     47 
     48 //===----------------------------------------------------------------------===//
     49 //                           UnaryInstruction Class
     50 //===----------------------------------------------------------------------===//
     51 
     52 // Out of line virtual method, so the vtable, etc has a home.
     53 UnaryInstruction::~UnaryInstruction() {
     54 }
     55 
     56 //===----------------------------------------------------------------------===//
     57 //                              SelectInst Class
     58 //===----------------------------------------------------------------------===//
     59 
     60 /// areInvalidOperands - Return a string if the specified operands are invalid
     61 /// for a select operation, otherwise return null.
     62 const char *SelectInst::areInvalidOperands(Value *Op0, Value *Op1, Value *Op2) {
     63   if (Op1->getType() != Op2->getType())
     64     return "both values to select must have same type";
     65 
     66   if (VectorType *VT = dyn_cast<VectorType>(Op0->getType())) {
     67     // Vector select.
     68     if (VT->getElementType() != Type::getInt1Ty(Op0->getContext()))
     69       return "vector select condition element type must be i1";
     70     VectorType *ET = dyn_cast<VectorType>(Op1->getType());
     71     if (!ET)
     72       return "selected values for vector select must be vectors";
     73     if (ET->getNumElements() != VT->getNumElements())
     74       return "vector select requires selected vectors to have "
     75                    "the same vector length as select condition";
     76   } else if (Op0->getType() != Type::getInt1Ty(Op0->getContext())) {
     77     return "select condition must be i1 or <n x i1>";
     78   }
     79   return nullptr;
     80 }
     81 
     82 
     83 //===----------------------------------------------------------------------===//
     84 //                               PHINode Class
     85 //===----------------------------------------------------------------------===//
     86 
     87 PHINode::PHINode(const PHINode &PN)
     88   : Instruction(PN.getType(), Instruction::PHI,
     89                 allocHungoffUses(PN.getNumOperands()), PN.getNumOperands()),
     90     ReservedSpace(PN.getNumOperands()) {
     91   std::copy(PN.op_begin(), PN.op_end(), op_begin());
     92   std::copy(PN.block_begin(), PN.block_end(), block_begin());
     93   SubclassOptionalData = PN.SubclassOptionalData;
     94 }
     95 
     96 PHINode::~PHINode() {
     97   dropHungoffUses();
     98 }
     99 
    100 Use *PHINode::allocHungoffUses(unsigned N) const {
    101   // Allocate the array of Uses of the incoming values, followed by a pointer
    102   // (with bottom bit set) to the User, followed by the array of pointers to
    103   // the incoming basic blocks.
    104   size_t size = N * sizeof(Use) + sizeof(Use::UserRef)
    105     + N * sizeof(BasicBlock*);
    106   Use *Begin = static_cast<Use*>(::operator new(size));
    107   Use *End = Begin + N;
    108   (void) new(End) Use::UserRef(const_cast<PHINode*>(this), 1);
    109   return Use::initTags(Begin, End);
    110 }
    111 
    112 // removeIncomingValue - Remove an incoming value.  This is useful if a
    113 // predecessor basic block is deleted.
    114 Value *PHINode::removeIncomingValue(unsigned Idx, bool DeletePHIIfEmpty) {
    115   Value *Removed = getIncomingValue(Idx);
    116 
    117   // Move everything after this operand down.
    118   //
    119   // FIXME: we could just swap with the end of the list, then erase.  However,
    120   // clients might not expect this to happen.  The code as it is thrashes the
    121   // use/def lists, which is kinda lame.
    122   std::copy(op_begin() + Idx + 1, op_end(), op_begin() + Idx);
    123   std::copy(block_begin() + Idx + 1, block_end(), block_begin() + Idx);
    124 
    125   // Nuke the last value.
    126   Op<-1>().set(nullptr);
    127   --NumOperands;
    128 
    129   // If the PHI node is dead, because it has zero entries, nuke it now.
    130   if (getNumOperands() == 0 && DeletePHIIfEmpty) {
    131     // If anyone is using this PHI, make them use a dummy value instead...
    132     replaceAllUsesWith(UndefValue::get(getType()));
    133     eraseFromParent();
    134   }
    135   return Removed;
    136 }
    137 
    138 /// growOperands - grow operands - This grows the operand list in response
    139 /// to a push_back style of operation.  This grows the number of ops by 1.5
    140 /// times.
    141 ///
    142 void PHINode::growOperands() {
    143   unsigned e = getNumOperands();
    144   unsigned NumOps = e + e / 2;
    145   if (NumOps < 2) NumOps = 2;      // 2 op PHI nodes are VERY common.
    146 
    147   Use *OldOps = op_begin();
    148   BasicBlock **OldBlocks = block_begin();
    149 
    150   ReservedSpace = NumOps;
    151   OperandList = allocHungoffUses(ReservedSpace);
    152 
    153   std::copy(OldOps, OldOps + e, op_begin());
    154   std::copy(OldBlocks, OldBlocks + e, block_begin());
    155 
    156   Use::zap(OldOps, OldOps + e, true);
    157 }
    158 
    159 /// hasConstantValue - If the specified PHI node always merges together the same
    160 /// value, return the value, otherwise return null.
    161 Value *PHINode::hasConstantValue() const {
    162   // Exploit the fact that phi nodes always have at least one entry.
    163   Value *ConstantValue = getIncomingValue(0);
    164   for (unsigned i = 1, e = getNumIncomingValues(); i != e; ++i)
    165     if (getIncomingValue(i) != ConstantValue && getIncomingValue(i) != this) {
    166       if (ConstantValue != this)
    167         return nullptr; // Incoming values not all the same.
    168        // The case where the first value is this PHI.
    169       ConstantValue = getIncomingValue(i);
    170     }
    171   if (ConstantValue == this)
    172     return UndefValue::get(getType());
    173   return ConstantValue;
    174 }
    175 
    176 //===----------------------------------------------------------------------===//
    177 //                       LandingPadInst Implementation
    178 //===----------------------------------------------------------------------===//
    179 
    180 LandingPadInst::LandingPadInst(Type *RetTy, Value *PersonalityFn,
    181                                unsigned NumReservedValues, const Twine &NameStr,
    182                                Instruction *InsertBefore)
    183   : Instruction(RetTy, Instruction::LandingPad, nullptr, 0, InsertBefore) {
    184   init(PersonalityFn, 1 + NumReservedValues, NameStr);
    185 }
    186 
    187 LandingPadInst::LandingPadInst(Type *RetTy, Value *PersonalityFn,
    188                                unsigned NumReservedValues, const Twine &NameStr,
    189                                BasicBlock *InsertAtEnd)
    190   : Instruction(RetTy, Instruction::LandingPad, nullptr, 0, InsertAtEnd) {
    191   init(PersonalityFn, 1 + NumReservedValues, NameStr);
    192 }
    193 
    194 LandingPadInst::LandingPadInst(const LandingPadInst &LP)
    195   : Instruction(LP.getType(), Instruction::LandingPad,
    196                 allocHungoffUses(LP.getNumOperands()), LP.getNumOperands()),
    197     ReservedSpace(LP.getNumOperands()) {
    198   Use *OL = OperandList, *InOL = LP.OperandList;
    199   for (unsigned I = 0, E = ReservedSpace; I != E; ++I)
    200     OL[I] = InOL[I];
    201 
    202   setCleanup(LP.isCleanup());
    203 }
    204 
    205 LandingPadInst::~LandingPadInst() {
    206   dropHungoffUses();
    207 }
    208 
    209 LandingPadInst *LandingPadInst::Create(Type *RetTy, Value *PersonalityFn,
    210                                        unsigned NumReservedClauses,
    211                                        const Twine &NameStr,
    212                                        Instruction *InsertBefore) {
    213   return new LandingPadInst(RetTy, PersonalityFn, NumReservedClauses, NameStr,
    214                             InsertBefore);
    215 }
    216 
    217 LandingPadInst *LandingPadInst::Create(Type *RetTy, Value *PersonalityFn,
    218                                        unsigned NumReservedClauses,
    219                                        const Twine &NameStr,
    220                                        BasicBlock *InsertAtEnd) {
    221   return new LandingPadInst(RetTy, PersonalityFn, NumReservedClauses, NameStr,
    222                             InsertAtEnd);
    223 }
    224 
    225 void LandingPadInst::init(Value *PersFn, unsigned NumReservedValues,
    226                           const Twine &NameStr) {
    227   ReservedSpace = NumReservedValues;
    228   NumOperands = 1;
    229   OperandList = allocHungoffUses(ReservedSpace);
    230   OperandList[0] = PersFn;
    231   setName(NameStr);
    232   setCleanup(false);
    233 }
    234 
    235 /// growOperands - grow operands - This grows the operand list in response to a
    236 /// push_back style of operation. This grows the number of ops by 2 times.
    237 void LandingPadInst::growOperands(unsigned Size) {
    238   unsigned e = getNumOperands();
    239   if (ReservedSpace >= e + Size) return;
    240   ReservedSpace = (e + Size / 2) * 2;
    241 
    242   Use *NewOps = allocHungoffUses(ReservedSpace);
    243   Use *OldOps = OperandList;
    244   for (unsigned i = 0; i != e; ++i)
    245       NewOps[i] = OldOps[i];
    246 
    247   OperandList = NewOps;
    248   Use::zap(OldOps, OldOps + e, true);
    249 }
    250 
    251 void LandingPadInst::addClause(Constant *Val) {
    252   unsigned OpNo = getNumOperands();
    253   growOperands(1);
    254   assert(OpNo < ReservedSpace && "Growing didn't work!");
    255   ++NumOperands;
    256   OperandList[OpNo] = Val;
    257 }
    258 
    259 //===----------------------------------------------------------------------===//
    260 //                        CallInst Implementation
    261 //===----------------------------------------------------------------------===//
    262 
    263 CallInst::~CallInst() {
    264 }
    265 
    266 void CallInst::init(Value *Func, ArrayRef<Value *> Args, const Twine &NameStr) {
    267   assert(NumOperands == Args.size() + 1 && "NumOperands not set up?");
    268   Op<-1>() = Func;
    269 
    270 #ifndef NDEBUG
    271   FunctionType *FTy =
    272     cast<FunctionType>(cast<PointerType>(Func->getType())->getElementType());
    273 
    274   assert((Args.size() == FTy->getNumParams() ||
    275           (FTy->isVarArg() && Args.size() > FTy->getNumParams())) &&
    276          "Calling a function with bad signature!");
    277 
    278   for (unsigned i = 0; i != Args.size(); ++i)
    279     assert((i >= FTy->getNumParams() ||
    280             FTy->getParamType(i) == Args[i]->getType()) &&
    281            "Calling a function with a bad signature!");
    282 #endif
    283 
    284   std::copy(Args.begin(), Args.end(), op_begin());
    285   setName(NameStr);
    286 }
    287 
    288 void CallInst::init(Value *Func, const Twine &NameStr) {
    289   assert(NumOperands == 1 && "NumOperands not set up?");
    290   Op<-1>() = Func;
    291 
    292 #ifndef NDEBUG
    293   FunctionType *FTy =
    294     cast<FunctionType>(cast<PointerType>(Func->getType())->getElementType());
    295 
    296   assert(FTy->getNumParams() == 0 && "Calling a function with bad signature");
    297 #endif
    298 
    299   setName(NameStr);
    300 }
    301 
    302 CallInst::CallInst(Value *Func, const Twine &Name,
    303                    Instruction *InsertBefore)
    304   : Instruction(cast<FunctionType>(cast<PointerType>(Func->getType())
    305                                    ->getElementType())->getReturnType(),
    306                 Instruction::Call,
    307                 OperandTraits<CallInst>::op_end(this) - 1,
    308                 1, InsertBefore) {
    309   init(Func, Name);
    310 }
    311 
    312 CallInst::CallInst(Value *Func, const Twine &Name,
    313                    BasicBlock *InsertAtEnd)
    314   : Instruction(cast<FunctionType>(cast<PointerType>(Func->getType())
    315                                    ->getElementType())->getReturnType(),
    316                 Instruction::Call,
    317                 OperandTraits<CallInst>::op_end(this) - 1,
    318                 1, InsertAtEnd) {
    319   init(Func, Name);
    320 }
    321 
    322 CallInst::CallInst(const CallInst &CI)
    323   : Instruction(CI.getType(), Instruction::Call,
    324                 OperandTraits<CallInst>::op_end(this) - CI.getNumOperands(),
    325                 CI.getNumOperands()) {
    326   setAttributes(CI.getAttributes());
    327   setTailCallKind(CI.getTailCallKind());
    328   setCallingConv(CI.getCallingConv());
    329 
    330   std::copy(CI.op_begin(), CI.op_end(), op_begin());
    331   SubclassOptionalData = CI.SubclassOptionalData;
    332 }
    333 
    334 void CallInst::addAttribute(unsigned i, Attribute::AttrKind attr) {
    335   AttributeSet PAL = getAttributes();
    336   PAL = PAL.addAttribute(getContext(), i, attr);
    337   setAttributes(PAL);
    338 }
    339 
    340 void CallInst::removeAttribute(unsigned i, Attribute attr) {
    341   AttributeSet PAL = getAttributes();
    342   AttrBuilder B(attr);
    343   LLVMContext &Context = getContext();
    344   PAL = PAL.removeAttributes(Context, i,
    345                              AttributeSet::get(Context, i, B));
    346   setAttributes(PAL);
    347 }
    348 
    349 bool CallInst::hasFnAttrImpl(Attribute::AttrKind A) const {
    350   if (AttributeList.hasAttribute(AttributeSet::FunctionIndex, A))
    351     return true;
    352   if (const Function *F = getCalledFunction())
    353     return F->getAttributes().hasAttribute(AttributeSet::FunctionIndex, A);
    354   return false;
    355 }
    356 
    357 bool CallInst::paramHasAttr(unsigned i, Attribute::AttrKind A) const {
    358   if (AttributeList.hasAttribute(i, A))
    359     return true;
    360   if (const Function *F = getCalledFunction())
    361     return F->getAttributes().hasAttribute(i, A);
    362   return false;
    363 }
    364 
    365 /// IsConstantOne - Return true only if val is constant int 1
    366 static bool IsConstantOne(Value *val) {
    367   assert(val && "IsConstantOne does not work with NULL val");
    368   return isa<ConstantInt>(val) && cast<ConstantInt>(val)->isOne();
    369 }
    370 
    371 static Instruction *createMalloc(Instruction *InsertBefore,
    372                                  BasicBlock *InsertAtEnd, Type *IntPtrTy,
    373                                  Type *AllocTy, Value *AllocSize,
    374                                  Value *ArraySize, Function *MallocF,
    375                                  const Twine &Name) {
    376   assert(((!InsertBefore && InsertAtEnd) || (InsertBefore && !InsertAtEnd)) &&
    377          "createMalloc needs either InsertBefore or InsertAtEnd");
    378 
    379   // malloc(type) becomes:
    380   //       bitcast (i8* malloc(typeSize)) to type*
    381   // malloc(type, arraySize) becomes:
    382   //       bitcast (i8 *malloc(typeSize*arraySize)) to type*
    383   if (!ArraySize)
    384     ArraySize = ConstantInt::get(IntPtrTy, 1);
    385   else if (ArraySize->getType() != IntPtrTy) {
    386     if (InsertBefore)
    387       ArraySize = CastInst::CreateIntegerCast(ArraySize, IntPtrTy, false,
    388                                               "", InsertBefore);
    389     else
    390       ArraySize = CastInst::CreateIntegerCast(ArraySize, IntPtrTy, false,
    391                                               "", InsertAtEnd);
    392   }
    393 
    394   if (!IsConstantOne(ArraySize)) {
    395     if (IsConstantOne(AllocSize)) {
    396       AllocSize = ArraySize;         // Operand * 1 = Operand
    397     } else if (Constant *CO = dyn_cast<Constant>(ArraySize)) {
    398       Constant *Scale = ConstantExpr::getIntegerCast(CO, IntPtrTy,
    399                                                      false /*ZExt*/);
    400       // Malloc arg is constant product of type size and array size
    401       AllocSize = ConstantExpr::getMul(Scale, cast<Constant>(AllocSize));
    402     } else {
    403       // Multiply type size by the array size...
    404       if (InsertBefore)
    405         AllocSize = BinaryOperator::CreateMul(ArraySize, AllocSize,
    406                                               "mallocsize", InsertBefore);
    407       else
    408         AllocSize = BinaryOperator::CreateMul(ArraySize, AllocSize,
    409                                               "mallocsize", InsertAtEnd);
    410     }
    411   }
    412 
    413   assert(AllocSize->getType() == IntPtrTy && "malloc arg is wrong size");
    414   // Create the call to Malloc.
    415   BasicBlock* BB = InsertBefore ? InsertBefore->getParent() : InsertAtEnd;
    416   Module* M = BB->getParent()->getParent();
    417   Type *BPTy = Type::getInt8PtrTy(BB->getContext());
    418   Value *MallocFunc = MallocF;
    419   if (!MallocFunc)
    420     // prototype malloc as "void *malloc(size_t)"
    421     MallocFunc = M->getOrInsertFunction("malloc", BPTy, IntPtrTy, NULL);
    422   PointerType *AllocPtrType = PointerType::getUnqual(AllocTy);
    423   CallInst *MCall = nullptr;
    424   Instruction *Result = nullptr;
    425   if (InsertBefore) {
    426     MCall = CallInst::Create(MallocFunc, AllocSize, "malloccall", InsertBefore);
    427     Result = MCall;
    428     if (Result->getType() != AllocPtrType)
    429       // Create a cast instruction to convert to the right type...
    430       Result = new BitCastInst(MCall, AllocPtrType, Name, InsertBefore);
    431   } else {
    432     MCall = CallInst::Create(MallocFunc, AllocSize, "malloccall");
    433     Result = MCall;
    434     if (Result->getType() != AllocPtrType) {
    435       InsertAtEnd->getInstList().push_back(MCall);
    436       // Create a cast instruction to convert to the right type...
    437       Result = new BitCastInst(MCall, AllocPtrType, Name);
    438     }
    439   }
    440   MCall->setTailCall();
    441   if (Function *F = dyn_cast<Function>(MallocFunc)) {
    442     MCall->setCallingConv(F->getCallingConv());
    443     if (!F->doesNotAlias(0)) F->setDoesNotAlias(0);
    444   }
    445   assert(!MCall->getType()->isVoidTy() && "Malloc has void return type");
    446 
    447   return Result;
    448 }
    449 
    450 /// CreateMalloc - Generate the IR for a call to malloc:
    451 /// 1. Compute the malloc call's argument as the specified type's size,
    452 ///    possibly multiplied by the array size if the array size is not
    453 ///    constant 1.
    454 /// 2. Call malloc with that argument.
    455 /// 3. Bitcast the result of the malloc call to the specified type.
    456 Instruction *CallInst::CreateMalloc(Instruction *InsertBefore,
    457                                     Type *IntPtrTy, Type *AllocTy,
    458                                     Value *AllocSize, Value *ArraySize,
    459                                     Function * MallocF,
    460                                     const Twine &Name) {
    461   return createMalloc(InsertBefore, nullptr, IntPtrTy, AllocTy, AllocSize,
    462                       ArraySize, MallocF, Name);
    463 }
    464 
    465 /// CreateMalloc - Generate the IR for a call to malloc:
    466 /// 1. Compute the malloc call's argument as the specified type's size,
    467 ///    possibly multiplied by the array size if the array size is not
    468 ///    constant 1.
    469 /// 2. Call malloc with that argument.
    470 /// 3. Bitcast the result of the malloc call to the specified type.
    471 /// Note: This function does not add the bitcast to the basic block, that is the
    472 /// responsibility of the caller.
    473 Instruction *CallInst::CreateMalloc(BasicBlock *InsertAtEnd,
    474                                     Type *IntPtrTy, Type *AllocTy,
    475                                     Value *AllocSize, Value *ArraySize,
    476                                     Function *MallocF, const Twine &Name) {
    477   return createMalloc(nullptr, InsertAtEnd, IntPtrTy, AllocTy, AllocSize,
    478                       ArraySize, MallocF, Name);
    479 }
    480 
    481 static Instruction* createFree(Value* Source, Instruction *InsertBefore,
    482                                BasicBlock *InsertAtEnd) {
    483   assert(((!InsertBefore && InsertAtEnd) || (InsertBefore && !InsertAtEnd)) &&
    484          "createFree needs either InsertBefore or InsertAtEnd");
    485   assert(Source->getType()->isPointerTy() &&
    486          "Can not free something of nonpointer type!");
    487 
    488   BasicBlock* BB = InsertBefore ? InsertBefore->getParent() : InsertAtEnd;
    489   Module* M = BB->getParent()->getParent();
    490 
    491   Type *VoidTy = Type::getVoidTy(M->getContext());
    492   Type *IntPtrTy = Type::getInt8PtrTy(M->getContext());
    493   // prototype free as "void free(void*)"
    494   Value *FreeFunc = M->getOrInsertFunction("free", VoidTy, IntPtrTy, NULL);
    495   CallInst* Result = nullptr;
    496   Value *PtrCast = Source;
    497   if (InsertBefore) {
    498     if (Source->getType() != IntPtrTy)
    499       PtrCast = new BitCastInst(Source, IntPtrTy, "", InsertBefore);
    500     Result = CallInst::Create(FreeFunc, PtrCast, "", InsertBefore);
    501   } else {
    502     if (Source->getType() != IntPtrTy)
    503       PtrCast = new BitCastInst(Source, IntPtrTy, "", InsertAtEnd);
    504     Result = CallInst::Create(FreeFunc, PtrCast, "");
    505   }
    506   Result->setTailCall();
    507   if (Function *F = dyn_cast<Function>(FreeFunc))
    508     Result->setCallingConv(F->getCallingConv());
    509 
    510   return Result;
    511 }
    512 
    513 /// CreateFree - Generate the IR for a call to the builtin free function.
    514 Instruction * CallInst::CreateFree(Value* Source, Instruction *InsertBefore) {
    515   return createFree(Source, InsertBefore, nullptr);
    516 }
    517 
    518 /// CreateFree - Generate the IR for a call to the builtin free function.
    519 /// Note: This function does not add the call to the basic block, that is the
    520 /// responsibility of the caller.
    521 Instruction* CallInst::CreateFree(Value* Source, BasicBlock *InsertAtEnd) {
    522   Instruction* FreeCall = createFree(Source, nullptr, InsertAtEnd);
    523   assert(FreeCall && "CreateFree did not create a CallInst");
    524   return FreeCall;
    525 }
    526 
    527 //===----------------------------------------------------------------------===//
    528 //                        InvokeInst Implementation
    529 //===----------------------------------------------------------------------===//
    530 
    531 void InvokeInst::init(Value *Fn, BasicBlock *IfNormal, BasicBlock *IfException,
    532                       ArrayRef<Value *> Args, const Twine &NameStr) {
    533   assert(NumOperands == 3 + Args.size() && "NumOperands not set up?");
    534   Op<-3>() = Fn;
    535   Op<-2>() = IfNormal;
    536   Op<-1>() = IfException;
    537 
    538 #ifndef NDEBUG
    539   FunctionType *FTy =
    540     cast<FunctionType>(cast<PointerType>(Fn->getType())->getElementType());
    541 
    542   assert(((Args.size() == FTy->getNumParams()) ||
    543           (FTy->isVarArg() && Args.size() > FTy->getNumParams())) &&
    544          "Invoking a function with bad signature");
    545 
    546   for (unsigned i = 0, e = Args.size(); i != e; i++)
    547     assert((i >= FTy->getNumParams() ||
    548             FTy->getParamType(i) == Args[i]->getType()) &&
    549            "Invoking a function with a bad signature!");
    550 #endif
    551 
    552   std::copy(Args.begin(), Args.end(), op_begin());
    553   setName(NameStr);
    554 }
    555 
    556 InvokeInst::InvokeInst(const InvokeInst &II)
    557   : TerminatorInst(II.getType(), Instruction::Invoke,
    558                    OperandTraits<InvokeInst>::op_end(this)
    559                    - II.getNumOperands(),
    560                    II.getNumOperands()) {
    561   setAttributes(II.getAttributes());
    562   setCallingConv(II.getCallingConv());
    563   std::copy(II.op_begin(), II.op_end(), op_begin());
    564   SubclassOptionalData = II.SubclassOptionalData;
    565 }
    566 
    567 BasicBlock *InvokeInst::getSuccessorV(unsigned idx) const {
    568   return getSuccessor(idx);
    569 }
    570 unsigned InvokeInst::getNumSuccessorsV() const {
    571   return getNumSuccessors();
    572 }
    573 void InvokeInst::setSuccessorV(unsigned idx, BasicBlock *B) {
    574   return setSuccessor(idx, B);
    575 }
    576 
    577 bool InvokeInst::hasFnAttrImpl(Attribute::AttrKind A) const {
    578   if (AttributeList.hasAttribute(AttributeSet::FunctionIndex, A))
    579     return true;
    580   if (const Function *F = getCalledFunction())
    581     return F->getAttributes().hasAttribute(AttributeSet::FunctionIndex, A);
    582   return false;
    583 }
    584 
    585 bool InvokeInst::paramHasAttr(unsigned i, Attribute::AttrKind A) const {
    586   if (AttributeList.hasAttribute(i, A))
    587     return true;
    588   if (const Function *F = getCalledFunction())
    589     return F->getAttributes().hasAttribute(i, A);
    590   return false;
    591 }
    592 
    593 void InvokeInst::addAttribute(unsigned i, Attribute::AttrKind attr) {
    594   AttributeSet PAL = getAttributes();
    595   PAL = PAL.addAttribute(getContext(), i, attr);
    596   setAttributes(PAL);
    597 }
    598 
    599 void InvokeInst::removeAttribute(unsigned i, Attribute attr) {
    600   AttributeSet PAL = getAttributes();
    601   AttrBuilder B(attr);
    602   PAL = PAL.removeAttributes(getContext(), i,
    603                              AttributeSet::get(getContext(), i, B));
    604   setAttributes(PAL);
    605 }
    606 
    607 LandingPadInst *InvokeInst::getLandingPadInst() const {
    608   return cast<LandingPadInst>(getUnwindDest()->getFirstNonPHI());
    609 }
    610 
    611 //===----------------------------------------------------------------------===//
    612 //                        ReturnInst Implementation
    613 //===----------------------------------------------------------------------===//
    614 
    615 ReturnInst::ReturnInst(const ReturnInst &RI)
    616   : TerminatorInst(Type::getVoidTy(RI.getContext()), Instruction::Ret,
    617                    OperandTraits<ReturnInst>::op_end(this) -
    618                      RI.getNumOperands(),
    619                    RI.getNumOperands()) {
    620   if (RI.getNumOperands())
    621     Op<0>() = RI.Op<0>();
    622   SubclassOptionalData = RI.SubclassOptionalData;
    623 }
    624 
    625 ReturnInst::ReturnInst(LLVMContext &C, Value *retVal, Instruction *InsertBefore)
    626   : TerminatorInst(Type::getVoidTy(C), Instruction::Ret,
    627                    OperandTraits<ReturnInst>::op_end(this) - !!retVal, !!retVal,
    628                    InsertBefore) {
    629   if (retVal)
    630     Op<0>() = retVal;
    631 }
    632 ReturnInst::ReturnInst(LLVMContext &C, Value *retVal, BasicBlock *InsertAtEnd)
    633   : TerminatorInst(Type::getVoidTy(C), Instruction::Ret,
    634                    OperandTraits<ReturnInst>::op_end(this) - !!retVal, !!retVal,
    635                    InsertAtEnd) {
    636   if (retVal)
    637     Op<0>() = retVal;
    638 }
    639 ReturnInst::ReturnInst(LLVMContext &Context, BasicBlock *InsertAtEnd)
    640   : TerminatorInst(Type::getVoidTy(Context), Instruction::Ret,
    641                    OperandTraits<ReturnInst>::op_end(this), 0, InsertAtEnd) {
    642 }
    643 
    644 unsigned ReturnInst::getNumSuccessorsV() const {
    645   return getNumSuccessors();
    646 }
    647 
    648 /// Out-of-line ReturnInst method, put here so the C++ compiler can choose to
    649 /// emit the vtable for the class in this translation unit.
    650 void ReturnInst::setSuccessorV(unsigned idx, BasicBlock *NewSucc) {
    651   llvm_unreachable("ReturnInst has no successors!");
    652 }
    653 
    654 BasicBlock *ReturnInst::getSuccessorV(unsigned idx) const {
    655   llvm_unreachable("ReturnInst has no successors!");
    656 }
    657 
    658 ReturnInst::~ReturnInst() {
    659 }
    660 
    661 //===----------------------------------------------------------------------===//
    662 //                        ResumeInst Implementation
    663 //===----------------------------------------------------------------------===//
    664 
    665 ResumeInst::ResumeInst(const ResumeInst &RI)
    666   : TerminatorInst(Type::getVoidTy(RI.getContext()), Instruction::Resume,
    667                    OperandTraits<ResumeInst>::op_begin(this), 1) {
    668   Op<0>() = RI.Op<0>();
    669 }
    670 
    671 ResumeInst::ResumeInst(Value *Exn, Instruction *InsertBefore)
    672   : TerminatorInst(Type::getVoidTy(Exn->getContext()), Instruction::Resume,
    673                    OperandTraits<ResumeInst>::op_begin(this), 1, InsertBefore) {
    674   Op<0>() = Exn;
    675 }
    676 
    677 ResumeInst::ResumeInst(Value *Exn, BasicBlock *InsertAtEnd)
    678   : TerminatorInst(Type::getVoidTy(Exn->getContext()), Instruction::Resume,
    679                    OperandTraits<ResumeInst>::op_begin(this), 1, InsertAtEnd) {
    680   Op<0>() = Exn;
    681 }
    682 
    683 unsigned ResumeInst::getNumSuccessorsV() const {
    684   return getNumSuccessors();
    685 }
    686 
    687 void ResumeInst::setSuccessorV(unsigned idx, BasicBlock *NewSucc) {
    688   llvm_unreachable("ResumeInst has no successors!");
    689 }
    690 
    691 BasicBlock *ResumeInst::getSuccessorV(unsigned idx) const {
    692   llvm_unreachable("ResumeInst has no successors!");
    693 }
    694 
    695 //===----------------------------------------------------------------------===//
    696 //                      UnreachableInst Implementation
    697 //===----------------------------------------------------------------------===//
    698 
    699 UnreachableInst::UnreachableInst(LLVMContext &Context,
    700                                  Instruction *InsertBefore)
    701   : TerminatorInst(Type::getVoidTy(Context), Instruction::Unreachable,
    702                    nullptr, 0, InsertBefore) {
    703 }
    704 UnreachableInst::UnreachableInst(LLVMContext &Context, BasicBlock *InsertAtEnd)
    705   : TerminatorInst(Type::getVoidTy(Context), Instruction::Unreachable,
    706                    nullptr, 0, InsertAtEnd) {
    707 }
    708 
    709 unsigned UnreachableInst::getNumSuccessorsV() const {
    710   return getNumSuccessors();
    711 }
    712 
    713 void UnreachableInst::setSuccessorV(unsigned idx, BasicBlock *NewSucc) {
    714   llvm_unreachable("UnreachableInst has no successors!");
    715 }
    716 
    717 BasicBlock *UnreachableInst::getSuccessorV(unsigned idx) const {
    718   llvm_unreachable("UnreachableInst has no successors!");
    719 }
    720 
    721 //===----------------------------------------------------------------------===//
    722 //                        BranchInst Implementation
    723 //===----------------------------------------------------------------------===//
    724 
    725 void BranchInst::AssertOK() {
    726   if (isConditional())
    727     assert(getCondition()->getType()->isIntegerTy(1) &&
    728            "May only branch on boolean predicates!");
    729 }
    730 
    731 BranchInst::BranchInst(BasicBlock *IfTrue, Instruction *InsertBefore)
    732   : TerminatorInst(Type::getVoidTy(IfTrue->getContext()), Instruction::Br,
    733                    OperandTraits<BranchInst>::op_end(this) - 1,
    734                    1, InsertBefore) {
    735   assert(IfTrue && "Branch destination may not be null!");
    736   Op<-1>() = IfTrue;
    737 }
    738 BranchInst::BranchInst(BasicBlock *IfTrue, BasicBlock *IfFalse, Value *Cond,
    739                        Instruction *InsertBefore)
    740   : TerminatorInst(Type::getVoidTy(IfTrue->getContext()), Instruction::Br,
    741                    OperandTraits<BranchInst>::op_end(this) - 3,
    742                    3, InsertBefore) {
    743   Op<-1>() = IfTrue;
    744   Op<-2>() = IfFalse;
    745   Op<-3>() = Cond;
    746 #ifndef NDEBUG
    747   AssertOK();
    748 #endif
    749 }
    750 
    751 BranchInst::BranchInst(BasicBlock *IfTrue, BasicBlock *InsertAtEnd)
    752   : TerminatorInst(Type::getVoidTy(IfTrue->getContext()), Instruction::Br,
    753                    OperandTraits<BranchInst>::op_end(this) - 1,
    754                    1, InsertAtEnd) {
    755   assert(IfTrue && "Branch destination may not be null!");
    756   Op<-1>() = IfTrue;
    757 }
    758 
    759 BranchInst::BranchInst(BasicBlock *IfTrue, BasicBlock *IfFalse, Value *Cond,
    760            BasicBlock *InsertAtEnd)
    761   : TerminatorInst(Type::getVoidTy(IfTrue->getContext()), Instruction::Br,
    762                    OperandTraits<BranchInst>::op_end(this) - 3,
    763                    3, InsertAtEnd) {
    764   Op<-1>() = IfTrue;
    765   Op<-2>() = IfFalse;
    766   Op<-3>() = Cond;
    767 #ifndef NDEBUG
    768   AssertOK();
    769 #endif
    770 }
    771 
    772 
    773 BranchInst::BranchInst(const BranchInst &BI) :
    774   TerminatorInst(Type::getVoidTy(BI.getContext()), Instruction::Br,
    775                  OperandTraits<BranchInst>::op_end(this) - BI.getNumOperands(),
    776                  BI.getNumOperands()) {
    777   Op<-1>() = BI.Op<-1>();
    778   if (BI.getNumOperands() != 1) {
    779     assert(BI.getNumOperands() == 3 && "BR can have 1 or 3 operands!");
    780     Op<-3>() = BI.Op<-3>();
    781     Op<-2>() = BI.Op<-2>();
    782   }
    783   SubclassOptionalData = BI.SubclassOptionalData;
    784 }
    785 
    786 void BranchInst::swapSuccessors() {
    787   assert(isConditional() &&
    788          "Cannot swap successors of an unconditional branch");
    789   Op<-1>().swap(Op<-2>());
    790 
    791   // Update profile metadata if present and it matches our structural
    792   // expectations.
    793   MDNode *ProfileData = getMetadata(LLVMContext::MD_prof);
    794   if (!ProfileData || ProfileData->getNumOperands() != 3)
    795     return;
    796 
    797   // The first operand is the name. Fetch them backwards and build a new one.
    798   Value *Ops[] = {
    799     ProfileData->getOperand(0),
    800     ProfileData->getOperand(2),
    801     ProfileData->getOperand(1)
    802   };
    803   setMetadata(LLVMContext::MD_prof,
    804               MDNode::get(ProfileData->getContext(), Ops));
    805 }
    806 
    807 BasicBlock *BranchInst::getSuccessorV(unsigned idx) const {
    808   return getSuccessor(idx);
    809 }
    810 unsigned BranchInst::getNumSuccessorsV() const {
    811   return getNumSuccessors();
    812 }
    813 void BranchInst::setSuccessorV(unsigned idx, BasicBlock *B) {
    814   setSuccessor(idx, B);
    815 }
    816 
    817 
    818 //===----------------------------------------------------------------------===//
    819 //                        AllocaInst Implementation
    820 //===----------------------------------------------------------------------===//
    821 
    822 static Value *getAISize(LLVMContext &Context, Value *Amt) {
    823   if (!Amt)
    824     Amt = ConstantInt::get(Type::getInt32Ty(Context), 1);
    825   else {
    826     assert(!isa<BasicBlock>(Amt) &&
    827            "Passed basic block into allocation size parameter! Use other ctor");
    828     assert(Amt->getType()->isIntegerTy() &&
    829            "Allocation array size is not an integer!");
    830   }
    831   return Amt;
    832 }
    833 
    834 AllocaInst::AllocaInst(Type *Ty, Value *ArraySize,
    835                        const Twine &Name, Instruction *InsertBefore)
    836   : UnaryInstruction(PointerType::getUnqual(Ty), Alloca,
    837                      getAISize(Ty->getContext(), ArraySize), InsertBefore) {
    838   setAlignment(0);
    839   assert(!Ty->isVoidTy() && "Cannot allocate void!");
    840   setName(Name);
    841 }
    842 
    843 AllocaInst::AllocaInst(Type *Ty, Value *ArraySize,
    844                        const Twine &Name, BasicBlock *InsertAtEnd)
    845   : UnaryInstruction(PointerType::getUnqual(Ty), Alloca,
    846                      getAISize(Ty->getContext(), ArraySize), InsertAtEnd) {
    847   setAlignment(0);
    848   assert(!Ty->isVoidTy() && "Cannot allocate void!");
    849   setName(Name);
    850 }
    851 
    852 AllocaInst::AllocaInst(Type *Ty, const Twine &Name,
    853                        Instruction *InsertBefore)
    854   : UnaryInstruction(PointerType::getUnqual(Ty), Alloca,
    855                      getAISize(Ty->getContext(), nullptr), InsertBefore) {
    856   setAlignment(0);
    857   assert(!Ty->isVoidTy() && "Cannot allocate void!");
    858   setName(Name);
    859 }
    860 
    861 AllocaInst::AllocaInst(Type *Ty, const Twine &Name,
    862                        BasicBlock *InsertAtEnd)
    863   : UnaryInstruction(PointerType::getUnqual(Ty), Alloca,
    864                      getAISize(Ty->getContext(), nullptr), InsertAtEnd) {
    865   setAlignment(0);
    866   assert(!Ty->isVoidTy() && "Cannot allocate void!");
    867   setName(Name);
    868 }
    869 
    870 AllocaInst::AllocaInst(Type *Ty, Value *ArraySize, unsigned Align,
    871                        const Twine &Name, Instruction *InsertBefore)
    872   : UnaryInstruction(PointerType::getUnqual(Ty), Alloca,
    873                      getAISize(Ty->getContext(), ArraySize), InsertBefore) {
    874   setAlignment(Align);
    875   assert(!Ty->isVoidTy() && "Cannot allocate void!");
    876   setName(Name);
    877 }
    878 
    879 AllocaInst::AllocaInst(Type *Ty, Value *ArraySize, unsigned Align,
    880                        const Twine &Name, BasicBlock *InsertAtEnd)
    881   : UnaryInstruction(PointerType::getUnqual(Ty), Alloca,
    882                      getAISize(Ty->getContext(), ArraySize), InsertAtEnd) {
    883   setAlignment(Align);
    884   assert(!Ty->isVoidTy() && "Cannot allocate void!");
    885   setName(Name);
    886 }
    887 
    888 // Out of line virtual method, so the vtable, etc has a home.
    889 AllocaInst::~AllocaInst() {
    890 }
    891 
    892 void AllocaInst::setAlignment(unsigned Align) {
    893   assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
    894   assert(Align <= MaximumAlignment &&
    895          "Alignment is greater than MaximumAlignment!");
    896   setInstructionSubclassData((getSubclassDataFromInstruction() & ~31) |
    897                              (Log2_32(Align) + 1));
    898   assert(getAlignment() == Align && "Alignment representation error!");
    899 }
    900 
    901 bool AllocaInst::isArrayAllocation() const {
    902   if (ConstantInt *CI = dyn_cast<ConstantInt>(getOperand(0)))
    903     return !CI->isOne();
    904   return true;
    905 }
    906 
    907 Type *AllocaInst::getAllocatedType() const {
    908   return getType()->getElementType();
    909 }
    910 
    911 /// isStaticAlloca - Return true if this alloca is in the entry block of the
    912 /// function and is a constant size.  If so, the code generator will fold it
    913 /// into the prolog/epilog code, so it is basically free.
    914 bool AllocaInst::isStaticAlloca() const {
    915   // Must be constant size.
    916   if (!isa<ConstantInt>(getArraySize())) return false;
    917 
    918   // Must be in the entry block.
    919   const BasicBlock *Parent = getParent();
    920   return Parent == &Parent->getParent()->front() && !isUsedWithInAlloca();
    921 }
    922 
    923 //===----------------------------------------------------------------------===//
    924 //                           LoadInst Implementation
    925 //===----------------------------------------------------------------------===//
    926 
    927 void LoadInst::AssertOK() {
    928   assert(getOperand(0)->getType()->isPointerTy() &&
    929          "Ptr must have pointer type.");
    930   assert(!(isAtomic() && getAlignment() == 0) &&
    931          "Alignment required for atomic load");
    932 }
    933 
    934 LoadInst::LoadInst(Value *Ptr, const Twine &Name, Instruction *InsertBef)
    935   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
    936                      Load, Ptr, InsertBef) {
    937   setVolatile(false);
    938   setAlignment(0);
    939   setAtomic(NotAtomic);
    940   AssertOK();
    941   setName(Name);
    942 }
    943 
    944 LoadInst::LoadInst(Value *Ptr, const Twine &Name, BasicBlock *InsertAE)
    945   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
    946                      Load, Ptr, InsertAE) {
    947   setVolatile(false);
    948   setAlignment(0);
    949   setAtomic(NotAtomic);
    950   AssertOK();
    951   setName(Name);
    952 }
    953 
    954 LoadInst::LoadInst(Value *Ptr, const Twine &Name, bool isVolatile,
    955                    Instruction *InsertBef)
    956   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
    957                      Load, Ptr, InsertBef) {
    958   setVolatile(isVolatile);
    959   setAlignment(0);
    960   setAtomic(NotAtomic);
    961   AssertOK();
    962   setName(Name);
    963 }
    964 
    965 LoadInst::LoadInst(Value *Ptr, const Twine &Name, bool isVolatile,
    966                    BasicBlock *InsertAE)
    967   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
    968                      Load, Ptr, InsertAE) {
    969   setVolatile(isVolatile);
    970   setAlignment(0);
    971   setAtomic(NotAtomic);
    972   AssertOK();
    973   setName(Name);
    974 }
    975 
    976 LoadInst::LoadInst(Value *Ptr, const Twine &Name, bool isVolatile,
    977                    unsigned Align, Instruction *InsertBef)
    978   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
    979                      Load, Ptr, InsertBef) {
    980   setVolatile(isVolatile);
    981   setAlignment(Align);
    982   setAtomic(NotAtomic);
    983   AssertOK();
    984   setName(Name);
    985 }
    986 
    987 LoadInst::LoadInst(Value *Ptr, const Twine &Name, bool isVolatile,
    988                    unsigned Align, BasicBlock *InsertAE)
    989   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
    990                      Load, Ptr, InsertAE) {
    991   setVolatile(isVolatile);
    992   setAlignment(Align);
    993   setAtomic(NotAtomic);
    994   AssertOK();
    995   setName(Name);
    996 }
    997 
    998 LoadInst::LoadInst(Value *Ptr, const Twine &Name, bool isVolatile,
    999                    unsigned Align, AtomicOrdering Order,
   1000                    SynchronizationScope SynchScope,
   1001                    Instruction *InsertBef)
   1002   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
   1003                      Load, Ptr, InsertBef) {
   1004   setVolatile(isVolatile);
   1005   setAlignment(Align);
   1006   setAtomic(Order, SynchScope);
   1007   AssertOK();
   1008   setName(Name);
   1009 }
   1010 
   1011 LoadInst::LoadInst(Value *Ptr, const Twine &Name, bool isVolatile,
   1012                    unsigned Align, AtomicOrdering Order,
   1013                    SynchronizationScope SynchScope,
   1014                    BasicBlock *InsertAE)
   1015   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
   1016                      Load, Ptr, InsertAE) {
   1017   setVolatile(isVolatile);
   1018   setAlignment(Align);
   1019   setAtomic(Order, SynchScope);
   1020   AssertOK();
   1021   setName(Name);
   1022 }
   1023 
   1024 LoadInst::LoadInst(Value *Ptr, const char *Name, Instruction *InsertBef)
   1025   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
   1026                      Load, Ptr, InsertBef) {
   1027   setVolatile(false);
   1028   setAlignment(0);
   1029   setAtomic(NotAtomic);
   1030   AssertOK();
   1031   if (Name && Name[0]) setName(Name);
   1032 }
   1033 
   1034 LoadInst::LoadInst(Value *Ptr, const char *Name, BasicBlock *InsertAE)
   1035   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
   1036                      Load, Ptr, InsertAE) {
   1037   setVolatile(false);
   1038   setAlignment(0);
   1039   setAtomic(NotAtomic);
   1040   AssertOK();
   1041   if (Name && Name[0]) setName(Name);
   1042 }
   1043 
   1044 LoadInst::LoadInst(Value *Ptr, const char *Name, bool isVolatile,
   1045                    Instruction *InsertBef)
   1046 : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
   1047                    Load, Ptr, InsertBef) {
   1048   setVolatile(isVolatile);
   1049   setAlignment(0);
   1050   setAtomic(NotAtomic);
   1051   AssertOK();
   1052   if (Name && Name[0]) setName(Name);
   1053 }
   1054 
   1055 LoadInst::LoadInst(Value *Ptr, const char *Name, bool isVolatile,
   1056                    BasicBlock *InsertAE)
   1057   : UnaryInstruction(cast<PointerType>(Ptr->getType())->getElementType(),
   1058                      Load, Ptr, InsertAE) {
   1059   setVolatile(isVolatile);
   1060   setAlignment(0);
   1061   setAtomic(NotAtomic);
   1062   AssertOK();
   1063   if (Name && Name[0]) setName(Name);
   1064 }
   1065 
   1066 void LoadInst::setAlignment(unsigned Align) {
   1067   assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
   1068   assert(Align <= MaximumAlignment &&
   1069          "Alignment is greater than MaximumAlignment!");
   1070   setInstructionSubclassData((getSubclassDataFromInstruction() & ~(31 << 1)) |
   1071                              ((Log2_32(Align)+1)<<1));
   1072   assert(getAlignment() == Align && "Alignment representation error!");
   1073 }
   1074 
   1075 //===----------------------------------------------------------------------===//
   1076 //                           StoreInst Implementation
   1077 //===----------------------------------------------------------------------===//
   1078 
   1079 void StoreInst::AssertOK() {
   1080   assert(getOperand(0) && getOperand(1) && "Both operands must be non-null!");
   1081   assert(getOperand(1)->getType()->isPointerTy() &&
   1082          "Ptr must have pointer type!");
   1083   assert(getOperand(0)->getType() ==
   1084                  cast<PointerType>(getOperand(1)->getType())->getElementType()
   1085          && "Ptr must be a pointer to Val type!");
   1086   assert(!(isAtomic() && getAlignment() == 0) &&
   1087          "Alignment required for atomic store");
   1088 }
   1089 
   1090 
   1091 StoreInst::StoreInst(Value *val, Value *addr, Instruction *InsertBefore)
   1092   : Instruction(Type::getVoidTy(val->getContext()), Store,
   1093                 OperandTraits<StoreInst>::op_begin(this),
   1094                 OperandTraits<StoreInst>::operands(this),
   1095                 InsertBefore) {
   1096   Op<0>() = val;
   1097   Op<1>() = addr;
   1098   setVolatile(false);
   1099   setAlignment(0);
   1100   setAtomic(NotAtomic);
   1101   AssertOK();
   1102 }
   1103 
   1104 StoreInst::StoreInst(Value *val, Value *addr, BasicBlock *InsertAtEnd)
   1105   : Instruction(Type::getVoidTy(val->getContext()), Store,
   1106                 OperandTraits<StoreInst>::op_begin(this),
   1107                 OperandTraits<StoreInst>::operands(this),
   1108                 InsertAtEnd) {
   1109   Op<0>() = val;
   1110   Op<1>() = addr;
   1111   setVolatile(false);
   1112   setAlignment(0);
   1113   setAtomic(NotAtomic);
   1114   AssertOK();
   1115 }
   1116 
   1117 StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile,
   1118                      Instruction *InsertBefore)
   1119   : Instruction(Type::getVoidTy(val->getContext()), Store,
   1120                 OperandTraits<StoreInst>::op_begin(this),
   1121                 OperandTraits<StoreInst>::operands(this),
   1122                 InsertBefore) {
   1123   Op<0>() = val;
   1124   Op<1>() = addr;
   1125   setVolatile(isVolatile);
   1126   setAlignment(0);
   1127   setAtomic(NotAtomic);
   1128   AssertOK();
   1129 }
   1130 
   1131 StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile,
   1132                      unsigned Align, Instruction *InsertBefore)
   1133   : Instruction(Type::getVoidTy(val->getContext()), Store,
   1134                 OperandTraits<StoreInst>::op_begin(this),
   1135                 OperandTraits<StoreInst>::operands(this),
   1136                 InsertBefore) {
   1137   Op<0>() = val;
   1138   Op<1>() = addr;
   1139   setVolatile(isVolatile);
   1140   setAlignment(Align);
   1141   setAtomic(NotAtomic);
   1142   AssertOK();
   1143 }
   1144 
   1145 StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile,
   1146                      unsigned Align, AtomicOrdering Order,
   1147                      SynchronizationScope SynchScope,
   1148                      Instruction *InsertBefore)
   1149   : Instruction(Type::getVoidTy(val->getContext()), Store,
   1150                 OperandTraits<StoreInst>::op_begin(this),
   1151                 OperandTraits<StoreInst>::operands(this),
   1152                 InsertBefore) {
   1153   Op<0>() = val;
   1154   Op<1>() = addr;
   1155   setVolatile(isVolatile);
   1156   setAlignment(Align);
   1157   setAtomic(Order, SynchScope);
   1158   AssertOK();
   1159 }
   1160 
   1161 StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile,
   1162                      BasicBlock *InsertAtEnd)
   1163   : Instruction(Type::getVoidTy(val->getContext()), Store,
   1164                 OperandTraits<StoreInst>::op_begin(this),
   1165                 OperandTraits<StoreInst>::operands(this),
   1166                 InsertAtEnd) {
   1167   Op<0>() = val;
   1168   Op<1>() = addr;
   1169   setVolatile(isVolatile);
   1170   setAlignment(0);
   1171   setAtomic(NotAtomic);
   1172   AssertOK();
   1173 }
   1174 
   1175 StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile,
   1176                      unsigned Align, BasicBlock *InsertAtEnd)
   1177   : Instruction(Type::getVoidTy(val->getContext()), Store,
   1178                 OperandTraits<StoreInst>::op_begin(this),
   1179                 OperandTraits<StoreInst>::operands(this),
   1180                 InsertAtEnd) {
   1181   Op<0>() = val;
   1182   Op<1>() = addr;
   1183   setVolatile(isVolatile);
   1184   setAlignment(Align);
   1185   setAtomic(NotAtomic);
   1186   AssertOK();
   1187 }
   1188 
   1189 StoreInst::StoreInst(Value *val, Value *addr, bool isVolatile,
   1190                      unsigned Align, AtomicOrdering Order,
   1191                      SynchronizationScope SynchScope,
   1192                      BasicBlock *InsertAtEnd)
   1193   : Instruction(Type::getVoidTy(val->getContext()), Store,
   1194                 OperandTraits<StoreInst>::op_begin(this),
   1195                 OperandTraits<StoreInst>::operands(this),
   1196                 InsertAtEnd) {
   1197   Op<0>() = val;
   1198   Op<1>() = addr;
   1199   setVolatile(isVolatile);
   1200   setAlignment(Align);
   1201   setAtomic(Order, SynchScope);
   1202   AssertOK();
   1203 }
   1204 
   1205 void StoreInst::setAlignment(unsigned Align) {
   1206   assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
   1207   assert(Align <= MaximumAlignment &&
   1208          "Alignment is greater than MaximumAlignment!");
   1209   setInstructionSubclassData((getSubclassDataFromInstruction() & ~(31 << 1)) |
   1210                              ((Log2_32(Align)+1) << 1));
   1211   assert(getAlignment() == Align && "Alignment representation error!");
   1212 }
   1213 
   1214 //===----------------------------------------------------------------------===//
   1215 //                       AtomicCmpXchgInst Implementation
   1216 //===----------------------------------------------------------------------===//
   1217 
   1218 void AtomicCmpXchgInst::Init(Value *Ptr, Value *Cmp, Value *NewVal,
   1219                              AtomicOrdering SuccessOrdering,
   1220                              AtomicOrdering FailureOrdering,
   1221                              SynchronizationScope SynchScope) {
   1222   Op<0>() = Ptr;
   1223   Op<1>() = Cmp;
   1224   Op<2>() = NewVal;
   1225   setSuccessOrdering(SuccessOrdering);
   1226   setFailureOrdering(FailureOrdering);
   1227   setSynchScope(SynchScope);
   1228 
   1229   assert(getOperand(0) && getOperand(1) && getOperand(2) &&
   1230          "All operands must be non-null!");
   1231   assert(getOperand(0)->getType()->isPointerTy() &&
   1232          "Ptr must have pointer type!");
   1233   assert(getOperand(1)->getType() ==
   1234                  cast<PointerType>(getOperand(0)->getType())->getElementType()
   1235          && "Ptr must be a pointer to Cmp type!");
   1236   assert(getOperand(2)->getType() ==
   1237                  cast<PointerType>(getOperand(0)->getType())->getElementType()
   1238          && "Ptr must be a pointer to NewVal type!");
   1239   assert(SuccessOrdering != NotAtomic &&
   1240          "AtomicCmpXchg instructions must be atomic!");
   1241   assert(FailureOrdering != NotAtomic &&
   1242          "AtomicCmpXchg instructions must be atomic!");
   1243   assert(SuccessOrdering >= FailureOrdering &&
   1244          "AtomicCmpXchg success ordering must be at least as strong as fail");
   1245   assert(FailureOrdering != Release && FailureOrdering != AcquireRelease &&
   1246          "AtomicCmpXchg failure ordering cannot include release semantics");
   1247 }
   1248 
   1249 AtomicCmpXchgInst::AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal,
   1250                                      AtomicOrdering SuccessOrdering,
   1251                                      AtomicOrdering FailureOrdering,
   1252                                      SynchronizationScope SynchScope,
   1253                                      Instruction *InsertBefore)
   1254     : Instruction(
   1255           StructType::get(Cmp->getType(), Type::getInt1Ty(Cmp->getContext()),
   1256                           nullptr),
   1257           AtomicCmpXchg, OperandTraits<AtomicCmpXchgInst>::op_begin(this),
   1258           OperandTraits<AtomicCmpXchgInst>::operands(this), InsertBefore) {
   1259   Init(Ptr, Cmp, NewVal, SuccessOrdering, FailureOrdering, SynchScope);
   1260 }
   1261 
   1262 AtomicCmpXchgInst::AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal,
   1263                                      AtomicOrdering SuccessOrdering,
   1264                                      AtomicOrdering FailureOrdering,
   1265                                      SynchronizationScope SynchScope,
   1266                                      BasicBlock *InsertAtEnd)
   1267     : Instruction(
   1268           StructType::get(Cmp->getType(), Type::getInt1Ty(Cmp->getContext()),
   1269                           nullptr),
   1270           AtomicCmpXchg, OperandTraits<AtomicCmpXchgInst>::op_begin(this),
   1271           OperandTraits<AtomicCmpXchgInst>::operands(this), InsertAtEnd) {
   1272   Init(Ptr, Cmp, NewVal, SuccessOrdering, FailureOrdering, SynchScope);
   1273 }
   1274 
   1275 //===----------------------------------------------------------------------===//
   1276 //                       AtomicRMWInst Implementation
   1277 //===----------------------------------------------------------------------===//
   1278 
   1279 void AtomicRMWInst::Init(BinOp Operation, Value *Ptr, Value *Val,
   1280                          AtomicOrdering Ordering,
   1281                          SynchronizationScope SynchScope) {
   1282   Op<0>() = Ptr;
   1283   Op<1>() = Val;
   1284   setOperation(Operation);
   1285   setOrdering(Ordering);
   1286   setSynchScope(SynchScope);
   1287 
   1288   assert(getOperand(0) && getOperand(1) &&
   1289          "All operands must be non-null!");
   1290   assert(getOperand(0)->getType()->isPointerTy() &&
   1291          "Ptr must have pointer type!");
   1292   assert(getOperand(1)->getType() ==
   1293          cast<PointerType>(getOperand(0)->getType())->getElementType()
   1294          && "Ptr must be a pointer to Val type!");
   1295   assert(Ordering != NotAtomic &&
   1296          "AtomicRMW instructions must be atomic!");
   1297 }
   1298 
   1299 AtomicRMWInst::AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val,
   1300                              AtomicOrdering Ordering,
   1301                              SynchronizationScope SynchScope,
   1302                              Instruction *InsertBefore)
   1303   : Instruction(Val->getType(), AtomicRMW,
   1304                 OperandTraits<AtomicRMWInst>::op_begin(this),
   1305                 OperandTraits<AtomicRMWInst>::operands(this),
   1306                 InsertBefore) {
   1307   Init(Operation, Ptr, Val, Ordering, SynchScope);
   1308 }
   1309 
   1310 AtomicRMWInst::AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val,
   1311                              AtomicOrdering Ordering,
   1312                              SynchronizationScope SynchScope,
   1313                              BasicBlock *InsertAtEnd)
   1314   : Instruction(Val->getType(), AtomicRMW,
   1315                 OperandTraits<AtomicRMWInst>::op_begin(this),
   1316                 OperandTraits<AtomicRMWInst>::operands(this),
   1317                 InsertAtEnd) {
   1318   Init(Operation, Ptr, Val, Ordering, SynchScope);
   1319 }
   1320 
   1321 //===----------------------------------------------------------------------===//
   1322 //                       FenceInst Implementation
   1323 //===----------------------------------------------------------------------===//
   1324 
   1325 FenceInst::FenceInst(LLVMContext &C, AtomicOrdering Ordering,
   1326                      SynchronizationScope SynchScope,
   1327                      Instruction *InsertBefore)
   1328   : Instruction(Type::getVoidTy(C), Fence, nullptr, 0, InsertBefore) {
   1329   setOrdering(Ordering);
   1330   setSynchScope(SynchScope);
   1331 }
   1332 
   1333 FenceInst::FenceInst(LLVMContext &C, AtomicOrdering Ordering,
   1334                      SynchronizationScope SynchScope,
   1335                      BasicBlock *InsertAtEnd)
   1336   : Instruction(Type::getVoidTy(C), Fence, nullptr, 0, InsertAtEnd) {
   1337   setOrdering(Ordering);
   1338   setSynchScope(SynchScope);
   1339 }
   1340 
   1341 //===----------------------------------------------------------------------===//
   1342 //                       GetElementPtrInst Implementation
   1343 //===----------------------------------------------------------------------===//
   1344 
   1345 void GetElementPtrInst::init(Value *Ptr, ArrayRef<Value *> IdxList,
   1346                              const Twine &Name) {
   1347   assert(NumOperands == 1 + IdxList.size() && "NumOperands not initialized?");
   1348   OperandList[0] = Ptr;
   1349   std::copy(IdxList.begin(), IdxList.end(), op_begin() + 1);
   1350   setName(Name);
   1351 }
   1352 
   1353 GetElementPtrInst::GetElementPtrInst(const GetElementPtrInst &GEPI)
   1354   : Instruction(GEPI.getType(), GetElementPtr,
   1355                 OperandTraits<GetElementPtrInst>::op_end(this)
   1356                 - GEPI.getNumOperands(),
   1357                 GEPI.getNumOperands()) {
   1358   std::copy(GEPI.op_begin(), GEPI.op_end(), op_begin());
   1359   SubclassOptionalData = GEPI.SubclassOptionalData;
   1360 }
   1361 
   1362 /// getIndexedType - Returns the type of the element that would be accessed with
   1363 /// a gep instruction with the specified parameters.
   1364 ///
   1365 /// The Idxs pointer should point to a continuous piece of memory containing the
   1366 /// indices, either as Value* or uint64_t.
   1367 ///
   1368 /// A null type is returned if the indices are invalid for the specified
   1369 /// pointer type.
   1370 ///
   1371 template <typename IndexTy>
   1372 static Type *getIndexedTypeInternal(Type *Ptr, ArrayRef<IndexTy> IdxList) {
   1373   PointerType *PTy = dyn_cast<PointerType>(Ptr->getScalarType());
   1374   if (!PTy) return nullptr;   // Type isn't a pointer type!
   1375   Type *Agg = PTy->getElementType();
   1376 
   1377   // Handle the special case of the empty set index set, which is always valid.
   1378   if (IdxList.empty())
   1379     return Agg;
   1380 
   1381   // If there is at least one index, the top level type must be sized, otherwise
   1382   // it cannot be 'stepped over'.
   1383   if (!Agg->isSized())
   1384     return nullptr;
   1385 
   1386   unsigned CurIdx = 1;
   1387   for (; CurIdx != IdxList.size(); ++CurIdx) {
   1388     CompositeType *CT = dyn_cast<CompositeType>(Agg);
   1389     if (!CT || CT->isPointerTy()) return nullptr;
   1390     IndexTy Index = IdxList[CurIdx];
   1391     if (!CT->indexValid(Index)) return nullptr;
   1392     Agg = CT->getTypeAtIndex(Index);
   1393   }
   1394   return CurIdx == IdxList.size() ? Agg : nullptr;
   1395 }
   1396 
   1397 Type *GetElementPtrInst::getIndexedType(Type *Ptr, ArrayRef<Value *> IdxList) {
   1398   return getIndexedTypeInternal(Ptr, IdxList);
   1399 }
   1400 
   1401 Type *GetElementPtrInst::getIndexedType(Type *Ptr,
   1402                                         ArrayRef<Constant *> IdxList) {
   1403   return getIndexedTypeInternal(Ptr, IdxList);
   1404 }
   1405 
   1406 Type *GetElementPtrInst::getIndexedType(Type *Ptr, ArrayRef<uint64_t> IdxList) {
   1407   return getIndexedTypeInternal(Ptr, IdxList);
   1408 }
   1409 
   1410 /// hasAllZeroIndices - Return true if all of the indices of this GEP are
   1411 /// zeros.  If so, the result pointer and the first operand have the same
   1412 /// value, just potentially different types.
   1413 bool GetElementPtrInst::hasAllZeroIndices() const {
   1414   for (unsigned i = 1, e = getNumOperands(); i != e; ++i) {
   1415     if (ConstantInt *CI = dyn_cast<ConstantInt>(getOperand(i))) {
   1416       if (!CI->isZero()) return false;
   1417     } else {
   1418       return false;
   1419     }
   1420   }
   1421   return true;
   1422 }
   1423 
   1424 /// hasAllConstantIndices - Return true if all of the indices of this GEP are
   1425 /// constant integers.  If so, the result pointer and the first operand have
   1426 /// a constant offset between them.
   1427 bool GetElementPtrInst::hasAllConstantIndices() const {
   1428   for (unsigned i = 1, e = getNumOperands(); i != e; ++i) {
   1429     if (!isa<ConstantInt>(getOperand(i)))
   1430       return false;
   1431   }
   1432   return true;
   1433 }
   1434 
   1435 void GetElementPtrInst::setIsInBounds(bool B) {
   1436   cast<GEPOperator>(this)->setIsInBounds(B);
   1437 }
   1438 
   1439 bool GetElementPtrInst::isInBounds() const {
   1440   return cast<GEPOperator>(this)->isInBounds();
   1441 }
   1442 
   1443 bool GetElementPtrInst::accumulateConstantOffset(const DataLayout &DL,
   1444                                                  APInt &Offset) const {
   1445   // Delegate to the generic GEPOperator implementation.
   1446   return cast<GEPOperator>(this)->accumulateConstantOffset(DL, Offset);
   1447 }
   1448 
   1449 //===----------------------------------------------------------------------===//
   1450 //                           ExtractElementInst Implementation
   1451 //===----------------------------------------------------------------------===//
   1452 
   1453 ExtractElementInst::ExtractElementInst(Value *Val, Value *Index,
   1454                                        const Twine &Name,
   1455                                        Instruction *InsertBef)
   1456   : Instruction(cast<VectorType>(Val->getType())->getElementType(),
   1457                 ExtractElement,
   1458                 OperandTraits<ExtractElementInst>::op_begin(this),
   1459                 2, InsertBef) {
   1460   assert(isValidOperands(Val, Index) &&
   1461          "Invalid extractelement instruction operands!");
   1462   Op<0>() = Val;
   1463   Op<1>() = Index;
   1464   setName(Name);
   1465 }
   1466 
   1467 ExtractElementInst::ExtractElementInst(Value *Val, Value *Index,
   1468                                        const Twine &Name,
   1469                                        BasicBlock *InsertAE)
   1470   : Instruction(cast<VectorType>(Val->getType())->getElementType(),
   1471                 ExtractElement,
   1472                 OperandTraits<ExtractElementInst>::op_begin(this),
   1473                 2, InsertAE) {
   1474   assert(isValidOperands(Val, Index) &&
   1475          "Invalid extractelement instruction operands!");
   1476 
   1477   Op<0>() = Val;
   1478   Op<1>() = Index;
   1479   setName(Name);
   1480 }
   1481 
   1482 
   1483 bool ExtractElementInst::isValidOperands(const Value *Val, const Value *Index) {
   1484   if (!Val->getType()->isVectorTy() || !Index->getType()->isIntegerTy())
   1485     return false;
   1486   return true;
   1487 }
   1488 
   1489 
   1490 //===----------------------------------------------------------------------===//
   1491 //                           InsertElementInst Implementation
   1492 //===----------------------------------------------------------------------===//
   1493 
   1494 InsertElementInst::InsertElementInst(Value *Vec, Value *Elt, Value *Index,
   1495                                      const Twine &Name,
   1496                                      Instruction *InsertBef)
   1497   : Instruction(Vec->getType(), InsertElement,
   1498                 OperandTraits<InsertElementInst>::op_begin(this),
   1499                 3, InsertBef) {
   1500   assert(isValidOperands(Vec, Elt, Index) &&
   1501          "Invalid insertelement instruction operands!");
   1502   Op<0>() = Vec;
   1503   Op<1>() = Elt;
   1504   Op<2>() = Index;
   1505   setName(Name);
   1506 }
   1507 
   1508 InsertElementInst::InsertElementInst(Value *Vec, Value *Elt, Value *Index,
   1509                                      const Twine &Name,
   1510                                      BasicBlock *InsertAE)
   1511   : Instruction(Vec->getType(), InsertElement,
   1512                 OperandTraits<InsertElementInst>::op_begin(this),
   1513                 3, InsertAE) {
   1514   assert(isValidOperands(Vec, Elt, Index) &&
   1515          "Invalid insertelement instruction operands!");
   1516 
   1517   Op<0>() = Vec;
   1518   Op<1>() = Elt;
   1519   Op<2>() = Index;
   1520   setName(Name);
   1521 }
   1522 
   1523 bool InsertElementInst::isValidOperands(const Value *Vec, const Value *Elt,
   1524                                         const Value *Index) {
   1525   if (!Vec->getType()->isVectorTy())
   1526     return false;   // First operand of insertelement must be vector type.
   1527 
   1528   if (Elt->getType() != cast<VectorType>(Vec->getType())->getElementType())
   1529     return false;// Second operand of insertelement must be vector element type.
   1530 
   1531   if (!Index->getType()->isIntegerTy())
   1532     return false;  // Third operand of insertelement must be i32.
   1533   return true;
   1534 }
   1535 
   1536 
   1537 //===----------------------------------------------------------------------===//
   1538 //                      ShuffleVectorInst Implementation
   1539 //===----------------------------------------------------------------------===//
   1540 
   1541 ShuffleVectorInst::ShuffleVectorInst(Value *V1, Value *V2, Value *Mask,
   1542                                      const Twine &Name,
   1543                                      Instruction *InsertBefore)
   1544 : Instruction(VectorType::get(cast<VectorType>(V1->getType())->getElementType(),
   1545                 cast<VectorType>(Mask->getType())->getNumElements()),
   1546               ShuffleVector,
   1547               OperandTraits<ShuffleVectorInst>::op_begin(this),
   1548               OperandTraits<ShuffleVectorInst>::operands(this),
   1549               InsertBefore) {
   1550   assert(isValidOperands(V1, V2, Mask) &&
   1551          "Invalid shuffle vector instruction operands!");
   1552   Op<0>() = V1;
   1553   Op<1>() = V2;
   1554   Op<2>() = Mask;
   1555   setName(Name);
   1556 }
   1557 
   1558 ShuffleVectorInst::ShuffleVectorInst(Value *V1, Value *V2, Value *Mask,
   1559                                      const Twine &Name,
   1560                                      BasicBlock *InsertAtEnd)
   1561 : Instruction(VectorType::get(cast<VectorType>(V1->getType())->getElementType(),
   1562                 cast<VectorType>(Mask->getType())->getNumElements()),
   1563               ShuffleVector,
   1564               OperandTraits<ShuffleVectorInst>::op_begin(this),
   1565               OperandTraits<ShuffleVectorInst>::operands(this),
   1566               InsertAtEnd) {
   1567   assert(isValidOperands(V1, V2, Mask) &&
   1568          "Invalid shuffle vector instruction operands!");
   1569 
   1570   Op<0>() = V1;
   1571   Op<1>() = V2;
   1572   Op<2>() = Mask;
   1573   setName(Name);
   1574 }
   1575 
   1576 bool ShuffleVectorInst::isValidOperands(const Value *V1, const Value *V2,
   1577                                         const Value *Mask) {
   1578   // V1 and V2 must be vectors of the same type.
   1579   if (!V1->getType()->isVectorTy() || V1->getType() != V2->getType())
   1580     return false;
   1581 
   1582   // Mask must be vector of i32.
   1583   VectorType *MaskTy = dyn_cast<VectorType>(Mask->getType());
   1584   if (!MaskTy || !MaskTy->getElementType()->isIntegerTy(32))
   1585     return false;
   1586 
   1587   // Check to see if Mask is valid.
   1588   if (isa<UndefValue>(Mask) || isa<ConstantAggregateZero>(Mask))
   1589     return true;
   1590 
   1591   if (const ConstantVector *MV = dyn_cast<ConstantVector>(Mask)) {
   1592     unsigned V1Size = cast<VectorType>(V1->getType())->getNumElements();
   1593     for (Value *Op : MV->operands()) {
   1594       if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
   1595         if (CI->uge(V1Size*2))
   1596           return false;
   1597       } else if (!isa<UndefValue>(Op)) {
   1598         return false;
   1599       }
   1600     }
   1601     return true;
   1602   }
   1603 
   1604   if (const ConstantDataSequential *CDS =
   1605         dyn_cast<ConstantDataSequential>(Mask)) {
   1606     unsigned V1Size = cast<VectorType>(V1->getType())->getNumElements();
   1607     for (unsigned i = 0, e = MaskTy->getNumElements(); i != e; ++i)
   1608       if (CDS->getElementAsInteger(i) >= V1Size*2)
   1609         return false;
   1610     return true;
   1611   }
   1612 
   1613   // The bitcode reader can create a place holder for a forward reference
   1614   // used as the shuffle mask. When this occurs, the shuffle mask will
   1615   // fall into this case and fail. To avoid this error, do this bit of
   1616   // ugliness to allow such a mask pass.
   1617   if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(Mask))
   1618     if (CE->getOpcode() == Instruction::UserOp1)
   1619       return true;
   1620 
   1621   return false;
   1622 }
   1623 
   1624 /// getMaskValue - Return the index from the shuffle mask for the specified
   1625 /// output result.  This is either -1 if the element is undef or a number less
   1626 /// than 2*numelements.
   1627 int ShuffleVectorInst::getMaskValue(Constant *Mask, unsigned i) {
   1628   assert(i < Mask->getType()->getVectorNumElements() && "Index out of range");
   1629   if (ConstantDataSequential *CDS =dyn_cast<ConstantDataSequential>(Mask))
   1630     return CDS->getElementAsInteger(i);
   1631   Constant *C = Mask->getAggregateElement(i);
   1632   if (isa<UndefValue>(C))
   1633     return -1;
   1634   return cast<ConstantInt>(C)->getZExtValue();
   1635 }
   1636 
   1637 /// getShuffleMask - Return the full mask for this instruction, where each
   1638 /// element is the element number and undef's are returned as -1.
   1639 void ShuffleVectorInst::getShuffleMask(Constant *Mask,
   1640                                        SmallVectorImpl<int> &Result) {
   1641   unsigned NumElts = Mask->getType()->getVectorNumElements();
   1642 
   1643   if (ConstantDataSequential *CDS=dyn_cast<ConstantDataSequential>(Mask)) {
   1644     for (unsigned i = 0; i != NumElts; ++i)
   1645       Result.push_back(CDS->getElementAsInteger(i));
   1646     return;
   1647   }
   1648   for (unsigned i = 0; i != NumElts; ++i) {
   1649     Constant *C = Mask->getAggregateElement(i);
   1650     Result.push_back(isa<UndefValue>(C) ? -1 :
   1651                      cast<ConstantInt>(C)->getZExtValue());
   1652   }
   1653 }
   1654 
   1655 
   1656 //===----------------------------------------------------------------------===//
   1657 //                             InsertValueInst Class
   1658 //===----------------------------------------------------------------------===//
   1659 
   1660 void InsertValueInst::init(Value *Agg, Value *Val, ArrayRef<unsigned> Idxs,
   1661                            const Twine &Name) {
   1662   assert(NumOperands == 2 && "NumOperands not initialized?");
   1663 
   1664   // There's no fundamental reason why we require at least one index
   1665   // (other than weirdness with &*IdxBegin being invalid; see
   1666   // getelementptr's init routine for example). But there's no
   1667   // present need to support it.
   1668   assert(Idxs.size() > 0 && "InsertValueInst must have at least one index");
   1669 
   1670   assert(ExtractValueInst::getIndexedType(Agg->getType(), Idxs) ==
   1671          Val->getType() && "Inserted value must match indexed type!");
   1672   Op<0>() = Agg;
   1673   Op<1>() = Val;
   1674 
   1675   Indices.append(Idxs.begin(), Idxs.end());
   1676   setName(Name);
   1677 }
   1678 
   1679 InsertValueInst::InsertValueInst(const InsertValueInst &IVI)
   1680   : Instruction(IVI.getType(), InsertValue,
   1681                 OperandTraits<InsertValueInst>::op_begin(this), 2),
   1682     Indices(IVI.Indices) {
   1683   Op<0>() = IVI.getOperand(0);
   1684   Op<1>() = IVI.getOperand(1);
   1685   SubclassOptionalData = IVI.SubclassOptionalData;
   1686 }
   1687 
   1688 //===----------------------------------------------------------------------===//
   1689 //                             ExtractValueInst Class
   1690 //===----------------------------------------------------------------------===//
   1691 
   1692 void ExtractValueInst::init(ArrayRef<unsigned> Idxs, const Twine &Name) {
   1693   assert(NumOperands == 1 && "NumOperands not initialized?");
   1694 
   1695   // There's no fundamental reason why we require at least one index.
   1696   // But there's no present need to support it.
   1697   assert(Idxs.size() > 0 && "ExtractValueInst must have at least one index");
   1698 
   1699   Indices.append(Idxs.begin(), Idxs.end());
   1700   setName(Name);
   1701 }
   1702 
   1703 ExtractValueInst::ExtractValueInst(const ExtractValueInst &EVI)
   1704   : UnaryInstruction(EVI.getType(), ExtractValue, EVI.getOperand(0)),
   1705     Indices(EVI.Indices) {
   1706   SubclassOptionalData = EVI.SubclassOptionalData;
   1707 }
   1708 
   1709 // getIndexedType - Returns the type of the element that would be extracted
   1710 // with an extractvalue instruction with the specified parameters.
   1711 //
   1712 // A null type is returned if the indices are invalid for the specified
   1713 // pointer type.
   1714 //
   1715 Type *ExtractValueInst::getIndexedType(Type *Agg,
   1716                                        ArrayRef<unsigned> Idxs) {
   1717   for (unsigned Index : Idxs) {
   1718     // We can't use CompositeType::indexValid(Index) here.
   1719     // indexValid() always returns true for arrays because getelementptr allows
   1720     // out-of-bounds indices. Since we don't allow those for extractvalue and
   1721     // insertvalue we need to check array indexing manually.
   1722     // Since the only other types we can index into are struct types it's just
   1723     // as easy to check those manually as well.
   1724     if (ArrayType *AT = dyn_cast<ArrayType>(Agg)) {
   1725       if (Index >= AT->getNumElements())
   1726         return nullptr;
   1727     } else if (StructType *ST = dyn_cast<StructType>(Agg)) {
   1728       if (Index >= ST->getNumElements())
   1729         return nullptr;
   1730     } else {
   1731       // Not a valid type to index into.
   1732       return nullptr;
   1733     }
   1734 
   1735     Agg = cast<CompositeType>(Agg)->getTypeAtIndex(Index);
   1736   }
   1737   return const_cast<Type*>(Agg);
   1738 }
   1739 
   1740 //===----------------------------------------------------------------------===//
   1741 //                             BinaryOperator Class
   1742 //===----------------------------------------------------------------------===//
   1743 
   1744 BinaryOperator::BinaryOperator(BinaryOps iType, Value *S1, Value *S2,
   1745                                Type *Ty, const Twine &Name,
   1746                                Instruction *InsertBefore)
   1747   : Instruction(Ty, iType,
   1748                 OperandTraits<BinaryOperator>::op_begin(this),
   1749                 OperandTraits<BinaryOperator>::operands(this),
   1750                 InsertBefore) {
   1751   Op<0>() = S1;
   1752   Op<1>() = S2;
   1753   init(iType);
   1754   setName(Name);
   1755 }
   1756 
   1757 BinaryOperator::BinaryOperator(BinaryOps iType, Value *S1, Value *S2,
   1758                                Type *Ty, const Twine &Name,
   1759                                BasicBlock *InsertAtEnd)
   1760   : Instruction(Ty, iType,
   1761                 OperandTraits<BinaryOperator>::op_begin(this),
   1762                 OperandTraits<BinaryOperator>::operands(this),
   1763                 InsertAtEnd) {
   1764   Op<0>() = S1;
   1765   Op<1>() = S2;
   1766   init(iType);
   1767   setName(Name);
   1768 }
   1769 
   1770 
   1771 void BinaryOperator::init(BinaryOps iType) {
   1772   Value *LHS = getOperand(0), *RHS = getOperand(1);
   1773   (void)LHS; (void)RHS; // Silence warnings.
   1774   assert(LHS->getType() == RHS->getType() &&
   1775          "Binary operator operand types must match!");
   1776 #ifndef NDEBUG
   1777   switch (iType) {
   1778   case Add: case Sub:
   1779   case Mul:
   1780     assert(getType() == LHS->getType() &&
   1781            "Arithmetic operation should return same type as operands!");
   1782     assert(getType()->isIntOrIntVectorTy() &&
   1783            "Tried to create an integer operation on a non-integer type!");
   1784     break;
   1785   case FAdd: case FSub:
   1786   case FMul:
   1787     assert(getType() == LHS->getType() &&
   1788            "Arithmetic operation should return same type as operands!");
   1789     assert(getType()->isFPOrFPVectorTy() &&
   1790            "Tried to create a floating-point operation on a "
   1791            "non-floating-point type!");
   1792     break;
   1793   case UDiv:
   1794   case SDiv:
   1795     assert(getType() == LHS->getType() &&
   1796            "Arithmetic operation should return same type as operands!");
   1797     assert((getType()->isIntegerTy() || (getType()->isVectorTy() &&
   1798             cast<VectorType>(getType())->getElementType()->isIntegerTy())) &&
   1799            "Incorrect operand type (not integer) for S/UDIV");
   1800     break;
   1801   case FDiv:
   1802     assert(getType() == LHS->getType() &&
   1803            "Arithmetic operation should return same type as operands!");
   1804     assert(getType()->isFPOrFPVectorTy() &&
   1805            "Incorrect operand type (not floating point) for FDIV");
   1806     break;
   1807   case URem:
   1808   case SRem:
   1809     assert(getType() == LHS->getType() &&
   1810            "Arithmetic operation should return same type as operands!");
   1811     assert((getType()->isIntegerTy() || (getType()->isVectorTy() &&
   1812             cast<VectorType>(getType())->getElementType()->isIntegerTy())) &&
   1813            "Incorrect operand type (not integer) for S/UREM");
   1814     break;
   1815   case FRem:
   1816     assert(getType() == LHS->getType() &&
   1817            "Arithmetic operation should return same type as operands!");
   1818     assert(getType()->isFPOrFPVectorTy() &&
   1819            "Incorrect operand type (not floating point) for FREM");
   1820     break;
   1821   case Shl:
   1822   case LShr:
   1823   case AShr:
   1824     assert(getType() == LHS->getType() &&
   1825            "Shift operation should return same type as operands!");
   1826     assert((getType()->isIntegerTy() ||
   1827             (getType()->isVectorTy() &&
   1828              cast<VectorType>(getType())->getElementType()->isIntegerTy())) &&
   1829            "Tried to create a shift operation on a non-integral type!");
   1830     break;
   1831   case And: case Or:
   1832   case Xor:
   1833     assert(getType() == LHS->getType() &&
   1834            "Logical operation should return same type as operands!");
   1835     assert((getType()->isIntegerTy() ||
   1836             (getType()->isVectorTy() &&
   1837              cast<VectorType>(getType())->getElementType()->isIntegerTy())) &&
   1838            "Tried to create a logical operation on a non-integral type!");
   1839     break;
   1840   default:
   1841     break;
   1842   }
   1843 #endif
   1844 }
   1845 
   1846 BinaryOperator *BinaryOperator::Create(BinaryOps Op, Value *S1, Value *S2,
   1847                                        const Twine &Name,
   1848                                        Instruction *InsertBefore) {
   1849   assert(S1->getType() == S2->getType() &&
   1850          "Cannot create binary operator with two operands of differing type!");
   1851   return new BinaryOperator(Op, S1, S2, S1->getType(), Name, InsertBefore);
   1852 }
   1853 
   1854 BinaryOperator *BinaryOperator::Create(BinaryOps Op, Value *S1, Value *S2,
   1855                                        const Twine &Name,
   1856                                        BasicBlock *InsertAtEnd) {
   1857   BinaryOperator *Res = Create(Op, S1, S2, Name);
   1858   InsertAtEnd->getInstList().push_back(Res);
   1859   return Res;
   1860 }
   1861 
   1862 BinaryOperator *BinaryOperator::CreateNeg(Value *Op, const Twine &Name,
   1863                                           Instruction *InsertBefore) {
   1864   Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
   1865   return new BinaryOperator(Instruction::Sub,
   1866                             zero, Op,
   1867                             Op->getType(), Name, InsertBefore);
   1868 }
   1869 
   1870 BinaryOperator *BinaryOperator::CreateNeg(Value *Op, const Twine &Name,
   1871                                           BasicBlock *InsertAtEnd) {
   1872   Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
   1873   return new BinaryOperator(Instruction::Sub,
   1874                             zero, Op,
   1875                             Op->getType(), Name, InsertAtEnd);
   1876 }
   1877 
   1878 BinaryOperator *BinaryOperator::CreateNSWNeg(Value *Op, const Twine &Name,
   1879                                              Instruction *InsertBefore) {
   1880   Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
   1881   return BinaryOperator::CreateNSWSub(zero, Op, Name, InsertBefore);
   1882 }
   1883 
   1884 BinaryOperator *BinaryOperator::CreateNSWNeg(Value *Op, const Twine &Name,
   1885                                              BasicBlock *InsertAtEnd) {
   1886   Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
   1887   return BinaryOperator::CreateNSWSub(zero, Op, Name, InsertAtEnd);
   1888 }
   1889 
   1890 BinaryOperator *BinaryOperator::CreateNUWNeg(Value *Op, const Twine &Name,
   1891                                              Instruction *InsertBefore) {
   1892   Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
   1893   return BinaryOperator::CreateNUWSub(zero, Op, Name, InsertBefore);
   1894 }
   1895 
   1896 BinaryOperator *BinaryOperator::CreateNUWNeg(Value *Op, const Twine &Name,
   1897                                              BasicBlock *InsertAtEnd) {
   1898   Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
   1899   return BinaryOperator::CreateNUWSub(zero, Op, Name, InsertAtEnd);
   1900 }
   1901 
   1902 BinaryOperator *BinaryOperator::CreateFNeg(Value *Op, const Twine &Name,
   1903                                            Instruction *InsertBefore) {
   1904   Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
   1905   return new BinaryOperator(Instruction::FSub, zero, Op,
   1906                             Op->getType(), Name, InsertBefore);
   1907 }
   1908 
   1909 BinaryOperator *BinaryOperator::CreateFNeg(Value *Op, const Twine &Name,
   1910                                            BasicBlock *InsertAtEnd) {
   1911   Value *zero = ConstantFP::getZeroValueForNegation(Op->getType());
   1912   return new BinaryOperator(Instruction::FSub, zero, Op,
   1913                             Op->getType(), Name, InsertAtEnd);
   1914 }
   1915 
   1916 BinaryOperator *BinaryOperator::CreateNot(Value *Op, const Twine &Name,
   1917                                           Instruction *InsertBefore) {
   1918   Constant *C = Constant::getAllOnesValue(Op->getType());
   1919   return new BinaryOperator(Instruction::Xor, Op, C,
   1920                             Op->getType(), Name, InsertBefore);
   1921 }
   1922 
   1923 BinaryOperator *BinaryOperator::CreateNot(Value *Op, const Twine &Name,
   1924                                           BasicBlock *InsertAtEnd) {
   1925   Constant *AllOnes = Constant::getAllOnesValue(Op->getType());
   1926   return new BinaryOperator(Instruction::Xor, Op, AllOnes,
   1927                             Op->getType(), Name, InsertAtEnd);
   1928 }
   1929 
   1930 
   1931 // isConstantAllOnes - Helper function for several functions below
   1932 static inline bool isConstantAllOnes(const Value *V) {
   1933   if (const Constant *C = dyn_cast<Constant>(V))
   1934     return C->isAllOnesValue();
   1935   return false;
   1936 }
   1937 
   1938 bool BinaryOperator::isNeg(const Value *V) {
   1939   if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(V))
   1940     if (Bop->getOpcode() == Instruction::Sub)
   1941       if (Constant* C = dyn_cast<Constant>(Bop->getOperand(0)))
   1942         return C->isNegativeZeroValue();
   1943   return false;
   1944 }
   1945 
   1946 bool BinaryOperator::isFNeg(const Value *V, bool IgnoreZeroSign) {
   1947   if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(V))
   1948     if (Bop->getOpcode() == Instruction::FSub)
   1949       if (Constant* C = dyn_cast<Constant>(Bop->getOperand(0))) {
   1950         if (!IgnoreZeroSign)
   1951           IgnoreZeroSign = cast<Instruction>(V)->hasNoSignedZeros();
   1952         return !IgnoreZeroSign ? C->isNegativeZeroValue() : C->isZeroValue();
   1953       }
   1954   return false;
   1955 }
   1956 
   1957 bool BinaryOperator::isNot(const Value *V) {
   1958   if (const BinaryOperator *Bop = dyn_cast<BinaryOperator>(V))
   1959     return (Bop->getOpcode() == Instruction::Xor &&
   1960             (isConstantAllOnes(Bop->getOperand(1)) ||
   1961              isConstantAllOnes(Bop->getOperand(0))));
   1962   return false;
   1963 }
   1964 
   1965 Value *BinaryOperator::getNegArgument(Value *BinOp) {
   1966   return cast<BinaryOperator>(BinOp)->getOperand(1);
   1967 }
   1968 
   1969 const Value *BinaryOperator::getNegArgument(const Value *BinOp) {
   1970   return getNegArgument(const_cast<Value*>(BinOp));
   1971 }
   1972 
   1973 Value *BinaryOperator::getFNegArgument(Value *BinOp) {
   1974   return cast<BinaryOperator>(BinOp)->getOperand(1);
   1975 }
   1976 
   1977 const Value *BinaryOperator::getFNegArgument(const Value *BinOp) {
   1978   return getFNegArgument(const_cast<Value*>(BinOp));
   1979 }
   1980 
   1981 Value *BinaryOperator::getNotArgument(Value *BinOp) {
   1982   assert(isNot(BinOp) && "getNotArgument on non-'not' instruction!");
   1983   BinaryOperator *BO = cast<BinaryOperator>(BinOp);
   1984   Value *Op0 = BO->getOperand(0);
   1985   Value *Op1 = BO->getOperand(1);
   1986   if (isConstantAllOnes(Op0)) return Op1;
   1987 
   1988   assert(isConstantAllOnes(Op1));
   1989   return Op0;
   1990 }
   1991 
   1992 const Value *BinaryOperator::getNotArgument(const Value *BinOp) {
   1993   return getNotArgument(const_cast<Value*>(BinOp));
   1994 }
   1995 
   1996 
   1997 // swapOperands - Exchange the two operands to this instruction.  This
   1998 // instruction is safe to use on any binary instruction and does not
   1999 // modify the semantics of the instruction.  If the instruction is
   2000 // order dependent (SetLT f.e.) the opcode is changed.
   2001 //
   2002 bool BinaryOperator::swapOperands() {
   2003   if (!isCommutative())
   2004     return true; // Can't commute operands
   2005   Op<0>().swap(Op<1>());
   2006   return false;
   2007 }
   2008 
   2009 void BinaryOperator::setHasNoUnsignedWrap(bool b) {
   2010   cast<OverflowingBinaryOperator>(this)->setHasNoUnsignedWrap(b);
   2011 }
   2012 
   2013 void BinaryOperator::setHasNoSignedWrap(bool b) {
   2014   cast<OverflowingBinaryOperator>(this)->setHasNoSignedWrap(b);
   2015 }
   2016 
   2017 void BinaryOperator::setIsExact(bool b) {
   2018   cast<PossiblyExactOperator>(this)->setIsExact(b);
   2019 }
   2020 
   2021 bool BinaryOperator::hasNoUnsignedWrap() const {
   2022   return cast<OverflowingBinaryOperator>(this)->hasNoUnsignedWrap();
   2023 }
   2024 
   2025 bool BinaryOperator::hasNoSignedWrap() const {
   2026   return cast<OverflowingBinaryOperator>(this)->hasNoSignedWrap();
   2027 }
   2028 
   2029 bool BinaryOperator::isExact() const {
   2030   return cast<PossiblyExactOperator>(this)->isExact();
   2031 }
   2032 
   2033 //===----------------------------------------------------------------------===//
   2034 //                             FPMathOperator Class
   2035 //===----------------------------------------------------------------------===//
   2036 
   2037 /// getFPAccuracy - Get the maximum error permitted by this operation in ULPs.
   2038 /// An accuracy of 0.0 means that the operation should be performed with the
   2039 /// default precision.
   2040 float FPMathOperator::getFPAccuracy() const {
   2041   const MDNode *MD =
   2042     cast<Instruction>(this)->getMetadata(LLVMContext::MD_fpmath);
   2043   if (!MD)
   2044     return 0.0;
   2045   ConstantFP *Accuracy = cast<ConstantFP>(MD->getOperand(0));
   2046   return Accuracy->getValueAPF().convertToFloat();
   2047 }
   2048 
   2049 
   2050 //===----------------------------------------------------------------------===//
   2051 //                                CastInst Class
   2052 //===----------------------------------------------------------------------===//
   2053 
   2054 void CastInst::anchor() {}
   2055 
   2056 // Just determine if this cast only deals with integral->integral conversion.
   2057 bool CastInst::isIntegerCast() const {
   2058   switch (getOpcode()) {
   2059     default: return false;
   2060     case Instruction::ZExt:
   2061     case Instruction::SExt:
   2062     case Instruction::Trunc:
   2063       return true;
   2064     case Instruction::BitCast:
   2065       return getOperand(0)->getType()->isIntegerTy() &&
   2066         getType()->isIntegerTy();
   2067   }
   2068 }
   2069 
   2070 bool CastInst::isLosslessCast() const {
   2071   // Only BitCast can be lossless, exit fast if we're not BitCast
   2072   if (getOpcode() != Instruction::BitCast)
   2073     return false;
   2074 
   2075   // Identity cast is always lossless
   2076   Type* SrcTy = getOperand(0)->getType();
   2077   Type* DstTy = getType();
   2078   if (SrcTy == DstTy)
   2079     return true;
   2080 
   2081   // Pointer to pointer is always lossless.
   2082   if (SrcTy->isPointerTy())
   2083     return DstTy->isPointerTy();
   2084   return false;  // Other types have no identity values
   2085 }
   2086 
   2087 /// This function determines if the CastInst does not require any bits to be
   2088 /// changed in order to effect the cast. Essentially, it identifies cases where
   2089 /// no code gen is necessary for the cast, hence the name no-op cast.  For
   2090 /// example, the following are all no-op casts:
   2091 /// # bitcast i32* %x to i8*
   2092 /// # bitcast <2 x i32> %x to <4 x i16>
   2093 /// # ptrtoint i32* %x to i32     ; on 32-bit plaforms only
   2094 /// @brief Determine if the described cast is a no-op.
   2095 bool CastInst::isNoopCast(Instruction::CastOps Opcode,
   2096                           Type *SrcTy,
   2097                           Type *DestTy,
   2098                           Type *IntPtrTy) {
   2099   switch (Opcode) {
   2100     default: llvm_unreachable("Invalid CastOp");
   2101     case Instruction::Trunc:
   2102     case Instruction::ZExt:
   2103     case Instruction::SExt:
   2104     case Instruction::FPTrunc:
   2105     case Instruction::FPExt:
   2106     case Instruction::UIToFP:
   2107     case Instruction::SIToFP:
   2108     case Instruction::FPToUI:
   2109     case Instruction::FPToSI:
   2110     case Instruction::AddrSpaceCast:
   2111       // TODO: Target informations may give a more accurate answer here.
   2112       return false;
   2113     case Instruction::BitCast:
   2114       return true;  // BitCast never modifies bits.
   2115     case Instruction::PtrToInt:
   2116       return IntPtrTy->getScalarSizeInBits() ==
   2117              DestTy->getScalarSizeInBits();
   2118     case Instruction::IntToPtr:
   2119       return IntPtrTy->getScalarSizeInBits() ==
   2120              SrcTy->getScalarSizeInBits();
   2121   }
   2122 }
   2123 
   2124 /// @brief Determine if a cast is a no-op.
   2125 bool CastInst::isNoopCast(Type *IntPtrTy) const {
   2126   return isNoopCast(getOpcode(), getOperand(0)->getType(), getType(), IntPtrTy);
   2127 }
   2128 
   2129 bool CastInst::isNoopCast(const DataLayout *DL) const {
   2130   if (!DL) {
   2131     // Assume maximum pointer size.
   2132     return isNoopCast(Type::getInt64Ty(getContext()));
   2133   }
   2134 
   2135   Type *PtrOpTy = nullptr;
   2136   if (getOpcode() == Instruction::PtrToInt)
   2137     PtrOpTy = getOperand(0)->getType();
   2138   else if (getOpcode() == Instruction::IntToPtr)
   2139     PtrOpTy = getType();
   2140 
   2141   Type *IntPtrTy = PtrOpTy
   2142                  ? DL->getIntPtrType(PtrOpTy)
   2143                  : DL->getIntPtrType(getContext(), 0);
   2144 
   2145   return isNoopCast(getOpcode(), getOperand(0)->getType(), getType(), IntPtrTy);
   2146 }
   2147 
   2148 /// This function determines if a pair of casts can be eliminated and what
   2149 /// opcode should be used in the elimination. This assumes that there are two
   2150 /// instructions like this:
   2151 /// *  %F = firstOpcode SrcTy %x to MidTy
   2152 /// *  %S = secondOpcode MidTy %F to DstTy
   2153 /// The function returns a resultOpcode so these two casts can be replaced with:
   2154 /// *  %Replacement = resultOpcode %SrcTy %x to DstTy
   2155 /// If no such cast is permited, the function returns 0.
   2156 unsigned CastInst::isEliminableCastPair(
   2157   Instruction::CastOps firstOp, Instruction::CastOps secondOp,
   2158   Type *SrcTy, Type *MidTy, Type *DstTy, Type *SrcIntPtrTy, Type *MidIntPtrTy,
   2159   Type *DstIntPtrTy) {
   2160   // Define the 144 possibilities for these two cast instructions. The values
   2161   // in this matrix determine what to do in a given situation and select the
   2162   // case in the switch below.  The rows correspond to firstOp, the columns
   2163   // correspond to secondOp.  In looking at the table below, keep in  mind
   2164   // the following cast properties:
   2165   //
   2166   //          Size Compare       Source               Destination
   2167   // Operator  Src ? Size   Type       Sign         Type       Sign
   2168   // -------- ------------ -------------------   ---------------------
   2169   // TRUNC         >       Integer      Any        Integral     Any
   2170   // ZEXT          <       Integral   Unsigned     Integer      Any
   2171   // SEXT          <       Integral    Signed      Integer      Any
   2172   // FPTOUI       n/a      FloatPt      n/a        Integral   Unsigned
   2173   // FPTOSI       n/a      FloatPt      n/a        Integral    Signed
   2174   // UITOFP       n/a      Integral   Unsigned     FloatPt      n/a
   2175   // SITOFP       n/a      Integral    Signed      FloatPt      n/a
   2176   // FPTRUNC       >       FloatPt      n/a        FloatPt      n/a
   2177   // FPEXT         <       FloatPt      n/a        FloatPt      n/a
   2178   // PTRTOINT     n/a      Pointer      n/a        Integral   Unsigned
   2179   // INTTOPTR     n/a      Integral   Unsigned     Pointer      n/a
   2180   // BITCAST       =       FirstClass   n/a       FirstClass    n/a
   2181   // ADDRSPCST    n/a      Pointer      n/a        Pointer      n/a
   2182   //
   2183   // NOTE: some transforms are safe, but we consider them to be non-profitable.
   2184   // For example, we could merge "fptoui double to i32" + "zext i32 to i64",
   2185   // into "fptoui double to i64", but this loses information about the range
   2186   // of the produced value (we no longer know the top-part is all zeros).
   2187   // Further this conversion is often much more expensive for typical hardware,
   2188   // and causes issues when building libgcc.  We disallow fptosi+sext for the
   2189   // same reason.
   2190   const unsigned numCastOps =
   2191     Instruction::CastOpsEnd - Instruction::CastOpsBegin;
   2192   static const uint8_t CastResults[numCastOps][numCastOps] = {
   2193     // T        F  F  U  S  F  F  P  I  B  A  -+
   2194     // R  Z  S  P  P  I  I  T  P  2  N  T  S   |
   2195     // U  E  E  2  2  2  2  R  E  I  T  C  C   +- secondOp
   2196     // N  X  X  U  S  F  F  N  X  N  2  V  V   |
   2197     // C  T  T  I  I  P  P  C  T  T  P  T  T  -+
   2198     {  1, 0, 0,99,99, 0, 0,99,99,99, 0, 3, 0}, // Trunc         -+
   2199     {  8, 1, 9,99,99, 2, 0,99,99,99, 2, 3, 0}, // ZExt           |
   2200     {  8, 0, 1,99,99, 0, 2,99,99,99, 0, 3, 0}, // SExt           |
   2201     {  0, 0, 0,99,99, 0, 0,99,99,99, 0, 3, 0}, // FPToUI         |
   2202     {  0, 0, 0,99,99, 0, 0,99,99,99, 0, 3, 0}, // FPToSI         |
   2203     { 99,99,99, 0, 0,99,99, 0, 0,99,99, 4, 0}, // UIToFP         +- firstOp
   2204     { 99,99,99, 0, 0,99,99, 0, 0,99,99, 4, 0}, // SIToFP         |
   2205     { 99,99,99, 0, 0,99,99, 1, 0,99,99, 4, 0}, // FPTrunc        |
   2206     { 99,99,99, 2, 2,99,99,10, 2,99,99, 4, 0}, // FPExt          |
   2207     {  1, 0, 0,99,99, 0, 0,99,99,99, 7, 3, 0}, // PtrToInt       |
   2208     { 99,99,99,99,99,99,99,99,99,11,99,15, 0}, // IntToPtr       |
   2209     {  5, 5, 5, 6, 6, 5, 5, 6, 6,16, 5, 1,14}, // BitCast        |
   2210     {  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,13,12}, // AddrSpaceCast -+
   2211   };
   2212 
   2213   // If either of the casts are a bitcast from scalar to vector, disallow the
   2214   // merging. However, bitcast of A->B->A are allowed.
   2215   bool isFirstBitcast  = (firstOp == Instruction::BitCast);
   2216   bool isSecondBitcast = (secondOp == Instruction::BitCast);
   2217   bool chainedBitcast  = (SrcTy == DstTy && isFirstBitcast && isSecondBitcast);
   2218 
   2219   // Check if any of the bitcasts convert scalars<->vectors.
   2220   if ((isFirstBitcast  && isa<VectorType>(SrcTy) != isa<VectorType>(MidTy)) ||
   2221       (isSecondBitcast && isa<VectorType>(MidTy) != isa<VectorType>(DstTy)))
   2222     // Unless we are bitcasing to the original type, disallow optimizations.
   2223     if (!chainedBitcast) return 0;
   2224 
   2225   int ElimCase = CastResults[firstOp-Instruction::CastOpsBegin]
   2226                             [secondOp-Instruction::CastOpsBegin];
   2227   switch (ElimCase) {
   2228     case 0:
   2229       // Categorically disallowed.
   2230       return 0;
   2231     case 1:
   2232       // Allowed, use first cast's opcode.
   2233       return firstOp;
   2234     case 2:
   2235       // Allowed, use second cast's opcode.
   2236       return secondOp;
   2237     case 3:
   2238       // No-op cast in second op implies firstOp as long as the DestTy
   2239       // is integer and we are not converting between a vector and a
   2240       // non-vector type.
   2241       if (!SrcTy->isVectorTy() && DstTy->isIntegerTy())
   2242         return firstOp;
   2243       return 0;
   2244     case 4:
   2245       // No-op cast in second op implies firstOp as long as the DestTy
   2246       // is floating point.
   2247       if (DstTy->isFloatingPointTy())
   2248         return firstOp;
   2249       return 0;
   2250     case 5:
   2251       // No-op cast in first op implies secondOp as long as the SrcTy
   2252       // is an integer.
   2253       if (SrcTy->isIntegerTy())
   2254         return secondOp;
   2255       return 0;
   2256     case 6:
   2257       // No-op cast in first op implies secondOp as long as the SrcTy
   2258       // is a floating point.
   2259       if (SrcTy->isFloatingPointTy())
   2260         return secondOp;
   2261       return 0;
   2262     case 7: {
   2263       // Cannot simplify if address spaces are different!
   2264       if (SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace())
   2265         return 0;
   2266 
   2267       unsigned MidSize = MidTy->getScalarSizeInBits();
   2268       // We can still fold this without knowing the actual sizes as long we
   2269       // know that the intermediate pointer is the largest possible
   2270       // pointer size.
   2271       // FIXME: Is this always true?
   2272       if (MidSize == 64)
   2273         return Instruction::BitCast;
   2274 
   2275       // ptrtoint, inttoptr -> bitcast (ptr -> ptr) if int size is >= ptr size.
   2276       if (!SrcIntPtrTy || DstIntPtrTy != SrcIntPtrTy)
   2277         return 0;
   2278       unsigned PtrSize = SrcIntPtrTy->getScalarSizeInBits();
   2279       if (MidSize >= PtrSize)
   2280         return Instruction::BitCast;
   2281       return 0;
   2282     }
   2283     case 8: {
   2284       // ext, trunc -> bitcast,    if the SrcTy and DstTy are same size
   2285       // ext, trunc -> ext,        if sizeof(SrcTy) < sizeof(DstTy)
   2286       // ext, trunc -> trunc,      if sizeof(SrcTy) > sizeof(DstTy)
   2287       unsigned SrcSize = SrcTy->getScalarSizeInBits();
   2288       unsigned DstSize = DstTy->getScalarSizeInBits();
   2289       if (SrcSize == DstSize)
   2290         return Instruction::BitCast;
   2291       else if (SrcSize < DstSize)
   2292         return firstOp;
   2293       return secondOp;
   2294     }
   2295     case 9:
   2296       // zext, sext -> zext, because sext can't sign extend after zext
   2297       return Instruction::ZExt;
   2298     case 10:
   2299       // fpext followed by ftrunc is allowed if the bit size returned to is
   2300       // the same as the original, in which case its just a bitcast
   2301       if (SrcTy == DstTy)
   2302         return Instruction::BitCast;
   2303       return 0; // If the types are not the same we can't eliminate it.
   2304     case 11: {
   2305       // inttoptr, ptrtoint -> bitcast if SrcSize<=PtrSize and SrcSize==DstSize
   2306       if (!MidIntPtrTy)
   2307         return 0;
   2308       unsigned PtrSize = MidIntPtrTy->getScalarSizeInBits();
   2309       unsigned SrcSize = SrcTy->getScalarSizeInBits();
   2310       unsigned DstSize = DstTy->getScalarSizeInBits();
   2311       if (SrcSize <= PtrSize && SrcSize == DstSize)
   2312         return Instruction::BitCast;
   2313       return 0;
   2314     }
   2315     case 12: {
   2316       // addrspacecast, addrspacecast -> bitcast,       if SrcAS == DstAS
   2317       // addrspacecast, addrspacecast -> addrspacecast, if SrcAS != DstAS
   2318       if (SrcTy->getPointerAddressSpace() != DstTy->getPointerAddressSpace())
   2319         return Instruction::AddrSpaceCast;
   2320       return Instruction::BitCast;
   2321     }
   2322     case 13:
   2323       // FIXME: this state can be merged with (1), but the following assert
   2324       // is useful to check the correcteness of the sequence due to semantic
   2325       // change of bitcast.
   2326       assert(
   2327         SrcTy->isPtrOrPtrVectorTy() &&
   2328         MidTy->isPtrOrPtrVectorTy() &&
   2329         DstTy->isPtrOrPtrVectorTy() &&
   2330         SrcTy->getPointerAddressSpace() != MidTy->getPointerAddressSpace() &&
   2331         MidTy->getPointerAddressSpace() == DstTy->getPointerAddressSpace() &&
   2332         "Illegal addrspacecast, bitcast sequence!");
   2333       // Allowed, use first cast's opcode
   2334       return firstOp;
   2335     case 14:
   2336       // bitcast, addrspacecast -> addrspacecast if the element type of
   2337       // bitcast's source is the same as that of addrspacecast's destination.
   2338       if (SrcTy->getPointerElementType() == DstTy->getPointerElementType())
   2339         return Instruction::AddrSpaceCast;
   2340       return 0;
   2341 
   2342     case 15:
   2343       // FIXME: this state can be merged with (1), but the following assert
   2344       // is useful to check the correcteness of the sequence due to semantic
   2345       // change of bitcast.
   2346       assert(
   2347         SrcTy->isIntOrIntVectorTy() &&
   2348         MidTy->isPtrOrPtrVectorTy() &&
   2349         DstTy->isPtrOrPtrVectorTy() &&
   2350         MidTy->getPointerAddressSpace() == DstTy->getPointerAddressSpace() &&
   2351         "Illegal inttoptr, bitcast sequence!");
   2352       // Allowed, use first cast's opcode
   2353       return firstOp;
   2354     case 16:
   2355       // FIXME: this state can be merged with (2), but the following assert
   2356       // is useful to check the correcteness of the sequence due to semantic
   2357       // change of bitcast.
   2358       assert(
   2359         SrcTy->isPtrOrPtrVectorTy() &&
   2360         MidTy->isPtrOrPtrVectorTy() &&
   2361         DstTy->isIntOrIntVectorTy() &&
   2362         SrcTy->getPointerAddressSpace() == MidTy->getPointerAddressSpace() &&
   2363         "Illegal bitcast, ptrtoint sequence!");
   2364       // Allowed, use second cast's opcode
   2365       return secondOp;
   2366     case 99:
   2367       // Cast combination can't happen (error in input). This is for all cases
   2368       // where the MidTy is not the same for the two cast instructions.
   2369       llvm_unreachable("Invalid Cast Combination");
   2370     default:
   2371       llvm_unreachable("Error in CastResults table!!!");
   2372   }
   2373 }
   2374 
   2375 CastInst *CastInst::Create(Instruction::CastOps op, Value *S, Type *Ty,
   2376   const Twine &Name, Instruction *InsertBefore) {
   2377   assert(castIsValid(op, S, Ty) && "Invalid cast!");
   2378   // Construct and return the appropriate CastInst subclass
   2379   switch (op) {
   2380   case Trunc:         return new TruncInst         (S, Ty, Name, InsertBefore);
   2381   case ZExt:          return new ZExtInst          (S, Ty, Name, InsertBefore);
   2382   case SExt:          return new SExtInst          (S, Ty, Name, InsertBefore);
   2383   case FPTrunc:       return new FPTruncInst       (S, Ty, Name, InsertBefore);
   2384   case FPExt:         return new FPExtInst         (S, Ty, Name, InsertBefore);
   2385   case UIToFP:        return new UIToFPInst        (S, Ty, Name, InsertBefore);
   2386   case SIToFP:        return new SIToFPInst        (S, Ty, Name, InsertBefore);
   2387   case FPToUI:        return new FPToUIInst        (S, Ty, Name, InsertBefore);
   2388   case FPToSI:        return new FPToSIInst        (S, Ty, Name, InsertBefore);
   2389   case PtrToInt:      return new PtrToIntInst      (S, Ty, Name, InsertBefore);
   2390   case IntToPtr:      return new IntToPtrInst      (S, Ty, Name, InsertBefore);
   2391   case BitCast:       return new BitCastInst       (S, Ty, Name, InsertBefore);
   2392   case AddrSpaceCast: return new AddrSpaceCastInst (S, Ty, Name, InsertBefore);
   2393   default: llvm_unreachable("Invalid opcode provided");
   2394   }
   2395 }
   2396 
   2397 CastInst *CastInst::Create(Instruction::CastOps op, Value *S, Type *Ty,
   2398   const Twine &Name, BasicBlock *InsertAtEnd) {
   2399   assert(castIsValid(op, S, Ty) && "Invalid cast!");
   2400   // Construct and return the appropriate CastInst subclass
   2401   switch (op) {
   2402   case Trunc:         return new TruncInst         (S, Ty, Name, InsertAtEnd);
   2403   case ZExt:          return new ZExtInst          (S, Ty, Name, InsertAtEnd);
   2404   case SExt:          return new SExtInst          (S, Ty, Name, InsertAtEnd);
   2405   case FPTrunc:       return new FPTruncInst       (S, Ty, Name, InsertAtEnd);
   2406   case FPExt:         return new FPExtInst         (S, Ty, Name, InsertAtEnd);
   2407   case UIToFP:        return new UIToFPInst        (S, Ty, Name, InsertAtEnd);
   2408   case SIToFP:        return new SIToFPInst        (S, Ty, Name, InsertAtEnd);
   2409   case FPToUI:        return new FPToUIInst        (S, Ty, Name, InsertAtEnd);
   2410   case FPToSI:        return new FPToSIInst        (S, Ty, Name, InsertAtEnd);
   2411   case PtrToInt:      return new PtrToIntInst      (S, Ty, Name, InsertAtEnd);
   2412   case IntToPtr:      return new IntToPtrInst      (S, Ty, Name, InsertAtEnd);
   2413   case BitCast:       return new BitCastInst       (S, Ty, Name, InsertAtEnd);
   2414   case AddrSpaceCast: return new AddrSpaceCastInst (S, Ty, Name, InsertAtEnd);
   2415   default: llvm_unreachable("Invalid opcode provided");
   2416   }
   2417 }
   2418 
   2419 CastInst *CastInst::CreateZExtOrBitCast(Value *S, Type *Ty,
   2420                                         const Twine &Name,
   2421                                         Instruction *InsertBefore) {
   2422   if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
   2423     return Create(Instruction::BitCast, S, Ty, Name, InsertBefore);
   2424   return Create(Instruction::ZExt, S, Ty, Name, InsertBefore);
   2425 }
   2426 
   2427 CastInst *CastInst::CreateZExtOrBitCast(Value *S, Type *Ty,
   2428                                         const Twine &Name,
   2429                                         BasicBlock *InsertAtEnd) {
   2430   if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
   2431     return Create(Instruction::BitCast, S, Ty, Name, InsertAtEnd);
   2432   return Create(Instruction::ZExt, S, Ty, Name, InsertAtEnd);
   2433 }
   2434 
   2435 CastInst *CastInst::CreateSExtOrBitCast(Value *S, Type *Ty,
   2436                                         const Twine &Name,
   2437                                         Instruction *InsertBefore) {
   2438   if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
   2439     return Create(Instruction::BitCast, S, Ty, Name, InsertBefore);
   2440   return Create(Instruction::SExt, S, Ty, Name, InsertBefore);
   2441 }
   2442 
   2443 CastInst *CastInst::CreateSExtOrBitCast(Value *S, Type *Ty,
   2444                                         const Twine &Name,
   2445                                         BasicBlock *InsertAtEnd) {
   2446   if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
   2447     return Create(Instruction::BitCast, S, Ty, Name, InsertAtEnd);
   2448   return Create(Instruction::SExt, S, Ty, Name, InsertAtEnd);
   2449 }
   2450 
   2451 CastInst *CastInst::CreateTruncOrBitCast(Value *S, Type *Ty,
   2452                                          const Twine &Name,
   2453                                          Instruction *InsertBefore) {
   2454   if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
   2455     return Create(Instruction::BitCast, S, Ty, Name, InsertBefore);
   2456   return Create(Instruction::Trunc, S, Ty, Name, InsertBefore);
   2457 }
   2458 
   2459 CastInst *CastInst::CreateTruncOrBitCast(Value *S, Type *Ty,
   2460                                          const Twine &Name,
   2461                                          BasicBlock *InsertAtEnd) {
   2462   if (S->getType()->getScalarSizeInBits() == Ty->getScalarSizeInBits())
   2463     return Create(Instruction::BitCast, S, Ty, Name, InsertAtEnd);
   2464   return Create(Instruction::Trunc, S, Ty, Name, InsertAtEnd);
   2465 }
   2466 
   2467 CastInst *CastInst::CreatePointerCast(Value *S, Type *Ty,
   2468                                       const Twine &Name,
   2469                                       BasicBlock *InsertAtEnd) {
   2470   assert(S->getType()->isPtrOrPtrVectorTy() && "Invalid cast");
   2471   assert((Ty->isIntOrIntVectorTy() || Ty->isPtrOrPtrVectorTy()) &&
   2472          "Invalid cast");
   2473   assert(Ty->isVectorTy() == S->getType()->isVectorTy() && "Invalid cast");
   2474   assert((!Ty->isVectorTy() ||
   2475           Ty->getVectorNumElements() == S->getType()->getVectorNumElements()) &&
   2476          "Invalid cast");
   2477 
   2478   if (Ty->isIntOrIntVectorTy())
   2479     return Create(Instruction::PtrToInt, S, Ty, Name, InsertAtEnd);
   2480 
   2481   Type *STy = S->getType();
   2482   if (STy->getPointerAddressSpace() != Ty->getPointerAddressSpace())
   2483     return Create(Instruction::AddrSpaceCast, S, Ty, Name, InsertAtEnd);
   2484 
   2485   return Create(Instruction::BitCast, S, Ty, Name, InsertAtEnd);
   2486 }
   2487 
   2488 /// @brief Create a BitCast or a PtrToInt cast instruction
   2489 CastInst *CastInst::CreatePointerCast(Value *S, Type *Ty,
   2490                                       const Twine &Name,
   2491                                       Instruction *InsertBefore) {
   2492   assert(S->getType()->isPtrOrPtrVectorTy() && "Invalid cast");
   2493   assert((Ty->isIntOrIntVectorTy() || Ty->isPtrOrPtrVectorTy()) &&
   2494          "Invalid cast");
   2495   assert(Ty->isVectorTy() == S->getType()->isVectorTy() && "Invalid cast");
   2496   assert((!Ty->isVectorTy() ||
   2497           Ty->getVectorNumElements() == S->getType()->getVectorNumElements()) &&
   2498          "Invalid cast");
   2499 
   2500   if (Ty->isIntOrIntVectorTy())
   2501     return Create(Instruction::PtrToInt, S, Ty, Name, InsertBefore);
   2502 
   2503   Type *STy = S->getType();
   2504   if (STy->getPointerAddressSpace() != Ty->getPointerAddressSpace())
   2505     return Create(Instruction::AddrSpaceCast, S, Ty, Name, InsertBefore);
   2506 
   2507   return Create(Instruction::BitCast, S, Ty, Name, InsertBefore);
   2508 }
   2509 
   2510 CastInst *CastInst::CreateIntegerCast(Value *C, Type *Ty,
   2511                                       bool isSigned, const Twine &Name,
   2512                                       Instruction *InsertBefore) {
   2513   assert(C->getType()->isIntOrIntVectorTy() && Ty->isIntOrIntVectorTy() &&
   2514          "Invalid integer cast");
   2515   unsigned SrcBits = C->getType()->getScalarSizeInBits();
   2516   unsigned DstBits = Ty->getScalarSizeInBits();
   2517   Instruction::CastOps opcode =
   2518     (SrcBits == DstBits ? Instruction::BitCast :
   2519      (SrcBits > DstBits ? Instruction::Trunc :
   2520       (isSigned ? Instruction::SExt : Instruction::ZExt)));
   2521   return Create(opcode, C, Ty, Name, InsertBefore);
   2522 }
   2523 
   2524 CastInst *CastInst::CreateIntegerCast(Value *C, Type *Ty,
   2525                                       bool isSigned, const Twine &Name,
   2526                                       BasicBlock *InsertAtEnd) {
   2527   assert(C->getType()->isIntOrIntVectorTy() && Ty->isIntOrIntVectorTy() &&
   2528          "Invalid cast");
   2529   unsigned SrcBits = C->getType()->getScalarSizeInBits();
   2530   unsigned DstBits = Ty->getScalarSizeInBits();
   2531   Instruction::CastOps opcode =
   2532     (SrcBits == DstBits ? Instruction::BitCast :
   2533      (SrcBits > DstBits ? Instruction::Trunc :
   2534       (isSigned ? Instruction::SExt : Instruction::ZExt)));
   2535   return Create(opcode, C, Ty, Name, InsertAtEnd);
   2536 }
   2537 
   2538 CastInst *CastInst::CreateFPCast(Value *C, Type *Ty,
   2539                                  const Twine &Name,
   2540                                  Instruction *InsertBefore) {
   2541   assert(C->getType()->isFPOrFPVectorTy() && Ty->isFPOrFPVectorTy() &&
   2542          "Invalid cast");
   2543   unsigned SrcBits = C->getType()->getScalarSizeInBits();
   2544   unsigned DstBits = Ty->getScalarSizeInBits();
   2545   Instruction::CastOps opcode =
   2546     (SrcBits == DstBits ? Instruction::BitCast :
   2547      (SrcBits > DstBits ? Instruction::FPTrunc : Instruction::FPExt));
   2548   return Create(opcode, C, Ty, Name, InsertBefore);
   2549 }
   2550 
   2551 CastInst *CastInst::CreateFPCast(Value *C, Type *Ty,
   2552                                  const Twine &Name,
   2553                                  BasicBlock *InsertAtEnd) {
   2554   assert(C->getType()->isFPOrFPVectorTy() && Ty->isFPOrFPVectorTy() &&
   2555          "Invalid cast");
   2556   unsigned SrcBits = C->getType()->getScalarSizeInBits();
   2557   unsigned DstBits = Ty->getScalarSizeInBits();
   2558   Instruction::CastOps opcode =
   2559     (SrcBits == DstBits ? Instruction::BitCast :
   2560      (SrcBits > DstBits ? Instruction::FPTrunc : Instruction::FPExt));
   2561   return Create(opcode, C, Ty, Name, InsertAtEnd);
   2562 }
   2563 
   2564 // Check whether it is valid to call getCastOpcode for these types.
   2565 // This routine must be kept in sync with getCastOpcode.
   2566 bool CastInst::isCastable(Type *SrcTy, Type *DestTy) {
   2567   if (!SrcTy->isFirstClassType() || !DestTy->isFirstClassType())
   2568     return false;
   2569 
   2570   if (SrcTy == DestTy)
   2571     return true;
   2572 
   2573   if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcTy))
   2574     if (VectorType *DestVecTy = dyn_cast<VectorType>(DestTy))
   2575       if (SrcVecTy->getNumElements() == DestVecTy->getNumElements()) {
   2576         // An element by element cast.  Valid if casting the elements is valid.
   2577         SrcTy = SrcVecTy->getElementType();
   2578         DestTy = DestVecTy->getElementType();
   2579       }
   2580 
   2581   // Get the bit sizes, we'll need these
   2582   unsigned SrcBits = SrcTy->getPrimitiveSizeInBits();   // 0 for ptr
   2583   unsigned DestBits = DestTy->getPrimitiveSizeInBits(); // 0 for ptr
   2584 
   2585   // Run through the possibilities ...
   2586   if (DestTy->isIntegerTy()) {               // Casting to integral
   2587     if (SrcTy->isIntegerTy()) {                // Casting from integral
   2588         return true;
   2589     } else if (SrcTy->isFloatingPointTy()) {   // Casting from floating pt
   2590       return true;
   2591     } else if (SrcTy->isVectorTy()) {          // Casting from vector
   2592       return DestBits == SrcBits;
   2593     } else {                                   // Casting from something else
   2594       return SrcTy->isPointerTy();
   2595     }
   2596   } else if (DestTy->isFloatingPointTy()) {  // Casting to floating pt
   2597     if (SrcTy->isIntegerTy()) {                // Casting from integral
   2598       return true;
   2599     } else if (SrcTy->isFloatingPointTy()) {   // Casting from floating pt
   2600       return true;
   2601     } else if (SrcTy->isVectorTy()) {          // Casting from vector
   2602       return DestBits == SrcBits;
   2603     } else {                                   // Casting from something else
   2604       return false;
   2605     }
   2606   } else if (DestTy->isVectorTy()) {         // Casting to vector
   2607     return DestBits == SrcBits;
   2608   } else if (DestTy->isPointerTy()) {        // Casting to pointer
   2609     if (SrcTy->isPointerTy()) {                // Casting from pointer
   2610       return true;
   2611     } else if (SrcTy->isIntegerTy()) {         // Casting from integral
   2612       return true;
   2613     } else {                                   // Casting from something else
   2614       return false;
   2615     }
   2616   } else if (DestTy->isX86_MMXTy()) {
   2617     if (SrcTy->isVectorTy()) {
   2618       return DestBits == SrcBits;       // 64-bit vector to MMX
   2619     } else {
   2620       return false;
   2621     }
   2622   } else {                                   // Casting to something else
   2623     return false;
   2624   }
   2625 }
   2626 
   2627 bool CastInst::isBitCastable(Type *SrcTy, Type *DestTy) {
   2628   if (!SrcTy->isFirstClassType() || !DestTy->isFirstClassType())
   2629     return false;
   2630 
   2631   if (SrcTy == DestTy)
   2632     return true;
   2633 
   2634   if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcTy)) {
   2635     if (VectorType *DestVecTy = dyn_cast<VectorType>(DestTy)) {
   2636       if (SrcVecTy->getNumElements() == DestVecTy->getNumElements()) {
   2637         // An element by element cast. Valid if casting the elements is valid.
   2638         SrcTy = SrcVecTy->getElementType();
   2639         DestTy = DestVecTy->getElementType();
   2640       }
   2641     }
   2642   }
   2643 
   2644   if (PointerType *DestPtrTy = dyn_cast<PointerType>(DestTy)) {
   2645     if (PointerType *SrcPtrTy = dyn_cast<PointerType>(SrcTy)) {
   2646       return SrcPtrTy->getAddressSpace() == DestPtrTy->getAddressSpace();
   2647     }
   2648   }
   2649 
   2650   unsigned SrcBits = SrcTy->getPrimitiveSizeInBits();   // 0 for ptr
   2651   unsigned DestBits = DestTy->getPrimitiveSizeInBits(); // 0 for ptr
   2652 
   2653   // Could still have vectors of pointers if the number of elements doesn't
   2654   // match
   2655   if (SrcBits == 0 || DestBits == 0)
   2656     return false;
   2657 
   2658   if (SrcBits != DestBits)
   2659     return false;
   2660 
   2661   if (DestTy->isX86_MMXTy() || SrcTy->isX86_MMXTy())
   2662     return false;
   2663 
   2664   return true;
   2665 }
   2666 
   2667 // Provide a way to get a "cast" where the cast opcode is inferred from the
   2668 // types and size of the operand. This, basically, is a parallel of the
   2669 // logic in the castIsValid function below.  This axiom should hold:
   2670 //   castIsValid( getCastOpcode(Val, Ty), Val, Ty)
   2671 // should not assert in castIsValid. In other words, this produces a "correct"
   2672 // casting opcode for the arguments passed to it.
   2673 // This routine must be kept in sync with isCastable.
   2674 Instruction::CastOps
   2675 CastInst::getCastOpcode(
   2676   const Value *Src, bool SrcIsSigned, Type *DestTy, bool DestIsSigned) {
   2677   Type *SrcTy = Src->getType();
   2678 
   2679   assert(SrcTy->isFirstClassType() && DestTy->isFirstClassType() &&
   2680          "Only first class types are castable!");
   2681 
   2682   if (SrcTy == DestTy)
   2683     return BitCast;
   2684 
   2685   // FIXME: Check address space sizes here
   2686   if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcTy))
   2687     if (VectorType *DestVecTy = dyn_cast<VectorType>(DestTy))
   2688       if (SrcVecTy->getNumElements() == DestVecTy->getNumElements()) {
   2689         // An element by element cast.  Find the appropriate opcode based on the
   2690         // element types.
   2691         SrcTy = SrcVecTy->getElementType();
   2692         DestTy = DestVecTy->getElementType();
   2693       }
   2694 
   2695   // Get the bit sizes, we'll need these
   2696   unsigned SrcBits = SrcTy->getPrimitiveSizeInBits();   // 0 for ptr
   2697   unsigned DestBits = DestTy->getPrimitiveSizeInBits(); // 0 for ptr
   2698 
   2699   // Run through the possibilities ...
   2700   if (DestTy->isIntegerTy()) {                      // Casting to integral
   2701     if (SrcTy->isIntegerTy()) {                     // Casting from integral
   2702       if (DestBits < SrcBits)
   2703         return Trunc;                               // int -> smaller int
   2704       else if (DestBits > SrcBits) {                // its an extension
   2705         if (SrcIsSigned)
   2706           return SExt;                              // signed -> SEXT
   2707         else
   2708           return ZExt;                              // unsigned -> ZEXT
   2709       } else {
   2710         return BitCast;                             // Same size, No-op cast
   2711       }
   2712     } else if (SrcTy->isFloatingPointTy()) {        // Casting from floating pt
   2713       if (DestIsSigned)
   2714         return FPToSI;                              // FP -> sint
   2715       else
   2716         return FPToUI;                              // FP -> uint
   2717     } else if (SrcTy->isVectorTy()) {
   2718       assert(DestBits == SrcBits &&
   2719              "Casting vector to integer of different width");
   2720       return BitCast;                             // Same size, no-op cast
   2721     } else {
   2722       assert(SrcTy->isPointerTy() &&
   2723              "Casting from a value that is not first-class type");
   2724       return PtrToInt;                              // ptr -> int
   2725     }
   2726   } else if (DestTy->isFloatingPointTy()) {         // Casting to floating pt
   2727     if (SrcTy->isIntegerTy()) {                     // Casting from integral
   2728       if (SrcIsSigned)
   2729         return SIToFP;                              // sint -> FP
   2730       else
   2731         return UIToFP;                              // uint -> FP
   2732     } else if (SrcTy->isFloatingPointTy()) {        // Casting from floating pt
   2733       if (DestBits < SrcBits) {
   2734         return FPTrunc;                             // FP -> smaller FP
   2735       } else if (DestBits > SrcBits) {
   2736         return FPExt;                               // FP -> larger FP
   2737       } else  {
   2738         return BitCast;                             // same size, no-op cast
   2739       }
   2740     } else if (SrcTy->isVectorTy()) {
   2741       assert(DestBits == SrcBits &&
   2742              "Casting vector to floating point of different width");
   2743       return BitCast;                             // same size, no-op cast
   2744     }
   2745     llvm_unreachable("Casting pointer or non-first class to float");
   2746   } else if (DestTy->isVectorTy()) {
   2747     assert(DestBits == SrcBits &&
   2748            "Illegal cast to vector (wrong type or size)");
   2749     return BitCast;
   2750   } else if (DestTy->isPointerTy()) {
   2751     if (SrcTy->isPointerTy()) {
   2752       if (DestTy->getPointerAddressSpace() != SrcTy->getPointerAddressSpace())
   2753         return AddrSpaceCast;
   2754       return BitCast;                               // ptr -> ptr
   2755     } else if (SrcTy->isIntegerTy()) {
   2756       return IntToPtr;                              // int -> ptr
   2757     }
   2758     llvm_unreachable("Casting pointer to other than pointer or int");
   2759   } else if (DestTy->isX86_MMXTy()) {
   2760     if (SrcTy->isVectorTy()) {
   2761       assert(DestBits == SrcBits && "Casting vector of wrong width to X86_MMX");
   2762       return BitCast;                               // 64-bit vector to MMX
   2763     }
   2764     llvm_unreachable("Illegal cast to X86_MMX");
   2765   }
   2766   llvm_unreachable("Casting to type that is not first-class");
   2767 }
   2768 
   2769 //===----------------------------------------------------------------------===//
   2770 //                    CastInst SubClass Constructors
   2771 //===----------------------------------------------------------------------===//
   2772 
   2773 /// Check that the construction parameters for a CastInst are correct. This
   2774 /// could be broken out into the separate constructors but it is useful to have
   2775 /// it in one place and to eliminate the redundant code for getting the sizes
   2776 /// of the types involved.
   2777 bool
   2778 CastInst::castIsValid(Instruction::CastOps op, Value *S, Type *DstTy) {
   2779 
   2780   // Check for type sanity on the arguments
   2781   Type *SrcTy = S->getType();
   2782 
   2783   // If this is a cast to the same type then it's trivially true.
   2784   if (SrcTy == DstTy)
   2785     return true;
   2786 
   2787   if (!SrcTy->isFirstClassType() || !DstTy->isFirstClassType() ||
   2788       SrcTy->isAggregateType() || DstTy->isAggregateType())
   2789     return false;
   2790 
   2791   // Get the size of the types in bits, we'll need this later
   2792   unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
   2793   unsigned DstBitSize = DstTy->getScalarSizeInBits();
   2794 
   2795   // If these are vector types, get the lengths of the vectors (using zero for
   2796   // scalar types means that checking that vector lengths match also checks that
   2797   // scalars are not being converted to vectors or vectors to scalars).
   2798   unsigned SrcLength = SrcTy->isVectorTy() ?
   2799     cast<VectorType>(SrcTy)->getNumElements() : 0;
   2800   unsigned DstLength = DstTy->isVectorTy() ?
   2801     cast<VectorType>(DstTy)->getNumElements() : 0;
   2802 
   2803   // Switch on the opcode provided
   2804   switch (op) {
   2805   default: return false; // This is an input error
   2806   case Instruction::Trunc:
   2807     return SrcTy->isIntOrIntVectorTy() && DstTy->isIntOrIntVectorTy() &&
   2808       SrcLength == DstLength && SrcBitSize > DstBitSize;
   2809   case Instruction::ZExt:
   2810     return SrcTy->isIntOrIntVectorTy() && DstTy->isIntOrIntVectorTy() &&
   2811       SrcLength == DstLength && SrcBitSize < DstBitSize;
   2812   case Instruction::SExt:
   2813     return SrcTy->isIntOrIntVectorTy() && DstTy->isIntOrIntVectorTy() &&
   2814       SrcLength == DstLength && SrcBitSize < DstBitSize;
   2815   case Instruction::FPTrunc:
   2816     return SrcTy->isFPOrFPVectorTy() && DstTy->isFPOrFPVectorTy() &&
   2817       SrcLength == DstLength && SrcBitSize > DstBitSize;
   2818   case Instruction::FPExt:
   2819     return SrcTy->isFPOrFPVectorTy() && DstTy->isFPOrFPVectorTy() &&
   2820       SrcLength == DstLength && SrcBitSize < DstBitSize;
   2821   case Instruction::UIToFP:
   2822   case Instruction::SIToFP:
   2823     return SrcTy->isIntOrIntVectorTy() && DstTy->isFPOrFPVectorTy() &&
   2824       SrcLength == DstLength;
   2825   case Instruction::FPToUI:
   2826   case Instruction::FPToSI:
   2827     return SrcTy->isFPOrFPVectorTy() && DstTy->isIntOrIntVectorTy() &&
   2828       SrcLength == DstLength;
   2829   case Instruction::PtrToInt:
   2830     if (isa<VectorType>(SrcTy) != isa<VectorType>(DstTy))
   2831       return false;
   2832     if (VectorType *VT = dyn_cast<VectorType>(SrcTy))
   2833       if (VT->getNumElements() != cast<VectorType>(DstTy)->getNumElements())
   2834         return false;
   2835     return SrcTy->getScalarType()->isPointerTy() &&
   2836            DstTy->getScalarType()->isIntegerTy();
   2837   case Instruction::IntToPtr:
   2838     if (isa<VectorType>(SrcTy) != isa<VectorType>(DstTy))
   2839       return false;
   2840     if (VectorType *VT = dyn_cast<VectorType>(SrcTy))
   2841       if (VT->getNumElements() != cast<VectorType>(DstTy)->getNumElements())
   2842         return false;
   2843     return SrcTy->getScalarType()->isIntegerTy() &&
   2844            DstTy->getScalarType()->isPointerTy();
   2845   case Instruction::BitCast: {
   2846     PointerType *SrcPtrTy = dyn_cast<PointerType>(SrcTy->getScalarType());
   2847     PointerType *DstPtrTy = dyn_cast<PointerType>(DstTy->getScalarType());
   2848 
   2849     // BitCast implies a no-op cast of type only. No bits change.
   2850     // However, you can't cast pointers to anything but pointers.
   2851     if (!SrcPtrTy != !DstPtrTy)
   2852       return false;
   2853 
   2854     // For non-pointer cases, the cast is okay if the source and destination bit
   2855     // widths are identical.
   2856     if (!SrcPtrTy)
   2857       return SrcTy->getPrimitiveSizeInBits() == DstTy->getPrimitiveSizeInBits();
   2858 
   2859     // If both are pointers then the address spaces must match.
   2860     if (SrcPtrTy->getAddressSpace() != DstPtrTy->getAddressSpace())
   2861       return false;
   2862 
   2863     // A vector of pointers must have the same number of elements.
   2864     if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcTy)) {
   2865       if (VectorType *DstVecTy = dyn_cast<VectorType>(DstTy))
   2866         return (SrcVecTy->getNumElements() == DstVecTy->getNumElements());
   2867 
   2868       return false;
   2869     }
   2870 
   2871     return true;
   2872   }
   2873   case Instruction::AddrSpaceCast: {
   2874     PointerType *SrcPtrTy = dyn_cast<PointerType>(SrcTy->getScalarType());
   2875     if (!SrcPtrTy)
   2876       return false;
   2877 
   2878     PointerType *DstPtrTy = dyn_cast<PointerType>(DstTy->getScalarType());
   2879     if (!DstPtrTy)
   2880       return false;
   2881 
   2882     if (SrcPtrTy->getAddressSpace() == DstPtrTy->getAddressSpace())
   2883       return false;
   2884 
   2885     if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcTy)) {
   2886       if (VectorType *DstVecTy = dyn_cast<VectorType>(DstTy))
   2887         return (SrcVecTy->getNumElements() == DstVecTy->getNumElements());
   2888 
   2889       return false;
   2890     }
   2891 
   2892     return true;
   2893   }
   2894   }
   2895 }
   2896 
   2897 TruncInst::TruncInst(
   2898   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   2899 ) : CastInst(Ty, Trunc, S, Name, InsertBefore) {
   2900   assert(castIsValid(getOpcode(), S, Ty) && "Illegal Trunc");
   2901 }
   2902 
   2903 TruncInst::TruncInst(
   2904   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   2905 ) : CastInst(Ty, Trunc, S, Name, InsertAtEnd) {
   2906   assert(castIsValid(getOpcode(), S, Ty) && "Illegal Trunc");
   2907 }
   2908 
   2909 ZExtInst::ZExtInst(
   2910   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   2911 )  : CastInst(Ty, ZExt, S, Name, InsertBefore) {
   2912   assert(castIsValid(getOpcode(), S, Ty) && "Illegal ZExt");
   2913 }
   2914 
   2915 ZExtInst::ZExtInst(
   2916   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   2917 )  : CastInst(Ty, ZExt, S, Name, InsertAtEnd) {
   2918   assert(castIsValid(getOpcode(), S, Ty) && "Illegal ZExt");
   2919 }
   2920 SExtInst::SExtInst(
   2921   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   2922 ) : CastInst(Ty, SExt, S, Name, InsertBefore) {
   2923   assert(castIsValid(getOpcode(), S, Ty) && "Illegal SExt");
   2924 }
   2925 
   2926 SExtInst::SExtInst(
   2927   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   2928 )  : CastInst(Ty, SExt, S, Name, InsertAtEnd) {
   2929   assert(castIsValid(getOpcode(), S, Ty) && "Illegal SExt");
   2930 }
   2931 
   2932 FPTruncInst::FPTruncInst(
   2933   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   2934 ) : CastInst(Ty, FPTrunc, S, Name, InsertBefore) {
   2935   assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPTrunc");
   2936 }
   2937 
   2938 FPTruncInst::FPTruncInst(
   2939   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   2940 ) : CastInst(Ty, FPTrunc, S, Name, InsertAtEnd) {
   2941   assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPTrunc");
   2942 }
   2943 
   2944 FPExtInst::FPExtInst(
   2945   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   2946 ) : CastInst(Ty, FPExt, S, Name, InsertBefore) {
   2947   assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPExt");
   2948 }
   2949 
   2950 FPExtInst::FPExtInst(
   2951   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   2952 ) : CastInst(Ty, FPExt, S, Name, InsertAtEnd) {
   2953   assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPExt");
   2954 }
   2955 
   2956 UIToFPInst::UIToFPInst(
   2957   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   2958 ) : CastInst(Ty, UIToFP, S, Name, InsertBefore) {
   2959   assert(castIsValid(getOpcode(), S, Ty) && "Illegal UIToFP");
   2960 }
   2961 
   2962 UIToFPInst::UIToFPInst(
   2963   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   2964 ) : CastInst(Ty, UIToFP, S, Name, InsertAtEnd) {
   2965   assert(castIsValid(getOpcode(), S, Ty) && "Illegal UIToFP");
   2966 }
   2967 
   2968 SIToFPInst::SIToFPInst(
   2969   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   2970 ) : CastInst(Ty, SIToFP, S, Name, InsertBefore) {
   2971   assert(castIsValid(getOpcode(), S, Ty) && "Illegal SIToFP");
   2972 }
   2973 
   2974 SIToFPInst::SIToFPInst(
   2975   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   2976 ) : CastInst(Ty, SIToFP, S, Name, InsertAtEnd) {
   2977   assert(castIsValid(getOpcode(), S, Ty) && "Illegal SIToFP");
   2978 }
   2979 
   2980 FPToUIInst::FPToUIInst(
   2981   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   2982 ) : CastInst(Ty, FPToUI, S, Name, InsertBefore) {
   2983   assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPToUI");
   2984 }
   2985 
   2986 FPToUIInst::FPToUIInst(
   2987   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   2988 ) : CastInst(Ty, FPToUI, S, Name, InsertAtEnd) {
   2989   assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPToUI");
   2990 }
   2991 
   2992 FPToSIInst::FPToSIInst(
   2993   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   2994 ) : CastInst(Ty, FPToSI, S, Name, InsertBefore) {
   2995   assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPToSI");
   2996 }
   2997 
   2998 FPToSIInst::FPToSIInst(
   2999   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   3000 ) : CastInst(Ty, FPToSI, S, Name, InsertAtEnd) {
   3001   assert(castIsValid(getOpcode(), S, Ty) && "Illegal FPToSI");
   3002 }
   3003 
   3004 PtrToIntInst::PtrToIntInst(
   3005   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   3006 ) : CastInst(Ty, PtrToInt, S, Name, InsertBefore) {
   3007   assert(castIsValid(getOpcode(), S, Ty) && "Illegal PtrToInt");
   3008 }
   3009 
   3010 PtrToIntInst::PtrToIntInst(
   3011   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   3012 ) : CastInst(Ty, PtrToInt, S, Name, InsertAtEnd) {
   3013   assert(castIsValid(getOpcode(), S, Ty) && "Illegal PtrToInt");
   3014 }
   3015 
   3016 IntToPtrInst::IntToPtrInst(
   3017   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   3018 ) : CastInst(Ty, IntToPtr, S, Name, InsertBefore) {
   3019   assert(castIsValid(getOpcode(), S, Ty) && "Illegal IntToPtr");
   3020 }
   3021 
   3022 IntToPtrInst::IntToPtrInst(
   3023   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   3024 ) : CastInst(Ty, IntToPtr, S, Name, InsertAtEnd) {
   3025   assert(castIsValid(getOpcode(), S, Ty) && "Illegal IntToPtr");
   3026 }
   3027 
   3028 BitCastInst::BitCastInst(
   3029   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   3030 ) : CastInst(Ty, BitCast, S, Name, InsertBefore) {
   3031   assert(castIsValid(getOpcode(), S, Ty) && "Illegal BitCast");
   3032 }
   3033 
   3034 BitCastInst::BitCastInst(
   3035   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   3036 ) : CastInst(Ty, BitCast, S, Name, InsertAtEnd) {
   3037   assert(castIsValid(getOpcode(), S, Ty) && "Illegal BitCast");
   3038 }
   3039 
   3040 AddrSpaceCastInst::AddrSpaceCastInst(
   3041   Value *S, Type *Ty, const Twine &Name, Instruction *InsertBefore
   3042 ) : CastInst(Ty, AddrSpaceCast, S, Name, InsertBefore) {
   3043   assert(castIsValid(getOpcode(), S, Ty) && "Illegal AddrSpaceCast");
   3044 }
   3045 
   3046 AddrSpaceCastInst::AddrSpaceCastInst(
   3047   Value *S, Type *Ty, const Twine &Name, BasicBlock *InsertAtEnd
   3048 ) : CastInst(Ty, AddrSpaceCast, S, Name, InsertAtEnd) {
   3049   assert(castIsValid(getOpcode(), S, Ty) && "Illegal AddrSpaceCast");
   3050 }
   3051 
   3052 //===----------------------------------------------------------------------===//
   3053 //                               CmpInst Classes
   3054 //===----------------------------------------------------------------------===//
   3055 
   3056 void CmpInst::anchor() {}
   3057 
   3058 CmpInst::CmpInst(Type *ty, OtherOps op, unsigned short predicate,
   3059                  Value *LHS, Value *RHS, const Twine &Name,
   3060                  Instruction *InsertBefore)
   3061   : Instruction(ty, op,
   3062                 OperandTraits<CmpInst>::op_begin(this),
   3063                 OperandTraits<CmpInst>::operands(this),
   3064                 InsertBefore) {
   3065     Op<0>() = LHS;
   3066     Op<1>() = RHS;
   3067   setPredicate((Predicate)predicate);
   3068   setName(Name);
   3069 }
   3070 
   3071 CmpInst::CmpInst(Type *ty, OtherOps op, unsigned short predicate,
   3072                  Value *LHS, Value *RHS, const Twine &Name,
   3073                  BasicBlock *InsertAtEnd)
   3074   : Instruction(ty, op,
   3075                 OperandTraits<CmpInst>::op_begin(this),
   3076                 OperandTraits<CmpInst>::operands(this),
   3077                 InsertAtEnd) {
   3078   Op<0>() = LHS;
   3079   Op<1>() = RHS;
   3080   setPredicate((Predicate)predicate);
   3081   setName(Name);
   3082 }
   3083 
   3084 CmpInst *
   3085 CmpInst::Create(OtherOps Op, unsigned short predicate,
   3086                 Value *S1, Value *S2,
   3087                 const Twine &Name, Instruction *InsertBefore) {
   3088   if (Op == Instruction::ICmp) {
   3089     if (InsertBefore)
   3090       return new ICmpInst(InsertBefore, CmpInst::Predicate(predicate),
   3091                           S1, S2, Name);
   3092     else
   3093       return new ICmpInst(CmpInst::Predicate(predicate),
   3094                           S1, S2, Name);
   3095   }
   3096 
   3097   if (InsertBefore)
   3098     return new FCmpInst(InsertBefore, CmpInst::Predicate(predicate),
   3099                         S1, S2, Name);
   3100   else
   3101     return new FCmpInst(CmpInst::Predicate(predicate),
   3102                         S1, S2, Name);
   3103 }
   3104 
   3105 CmpInst *
   3106 CmpInst::Create(OtherOps Op, unsigned short predicate, Value *S1, Value *S2,
   3107                 const Twine &Name, BasicBlock *InsertAtEnd) {
   3108   if (Op == Instruction::ICmp) {
   3109     return new ICmpInst(*InsertAtEnd, CmpInst::Predicate(predicate),
   3110                         S1, S2, Name);
   3111   }
   3112   return new FCmpInst(*InsertAtEnd, CmpInst::Predicate(predicate),
   3113                       S1, S2, Name);
   3114 }
   3115 
   3116 void CmpInst::swapOperands() {
   3117   if (ICmpInst *IC = dyn_cast<ICmpInst>(this))
   3118     IC->swapOperands();
   3119   else
   3120     cast<FCmpInst>(this)->swapOperands();
   3121 }
   3122 
   3123 bool CmpInst::isCommutative() const {
   3124   if (const ICmpInst *IC = dyn_cast<ICmpInst>(this))
   3125     return IC->isCommutative();
   3126   return cast<FCmpInst>(this)->isCommutative();
   3127 }
   3128 
   3129 bool CmpInst::isEquality() const {
   3130   if (const ICmpInst *IC = dyn_cast<ICmpInst>(this))
   3131     return IC->isEquality();
   3132   return cast<FCmpInst>(this)->isEquality();
   3133 }
   3134 
   3135 
   3136 CmpInst::Predicate CmpInst::getInversePredicate(Predicate pred) {
   3137   switch (pred) {
   3138     default: llvm_unreachable("Unknown cmp predicate!");
   3139     case ICMP_EQ: return ICMP_NE;
   3140     case ICMP_NE: return ICMP_EQ;
   3141     case ICMP_UGT: return ICMP_ULE;
   3142     case ICMP_ULT: return ICMP_UGE;
   3143     case ICMP_UGE: return ICMP_ULT;
   3144     case ICMP_ULE: return ICMP_UGT;
   3145     case ICMP_SGT: return ICMP_SLE;
   3146     case ICMP_SLT: return ICMP_SGE;
   3147     case ICMP_SGE: return ICMP_SLT;
   3148     case ICMP_SLE: return ICMP_SGT;
   3149 
   3150     case FCMP_OEQ: return FCMP_UNE;
   3151     case FCMP_ONE: return FCMP_UEQ;
   3152     case FCMP_OGT: return FCMP_ULE;
   3153     case FCMP_OLT: return FCMP_UGE;
   3154     case FCMP_OGE: return FCMP_ULT;
   3155     case FCMP_OLE: return FCMP_UGT;
   3156     case FCMP_UEQ: return FCMP_ONE;
   3157     case FCMP_UNE: return FCMP_OEQ;
   3158     case FCMP_UGT: return FCMP_OLE;
   3159     case FCMP_ULT: return FCMP_OGE;
   3160     case FCMP_UGE: return FCMP_OLT;
   3161     case FCMP_ULE: return FCMP_OGT;
   3162     case FCMP_ORD: return FCMP_UNO;
   3163     case FCMP_UNO: return FCMP_ORD;
   3164     case FCMP_TRUE: return FCMP_FALSE;
   3165     case FCMP_FALSE: return FCMP_TRUE;
   3166   }
   3167 }
   3168 
   3169 ICmpInst::Predicate ICmpInst::getSignedPredicate(Predicate pred) {
   3170   switch (pred) {
   3171     default: llvm_unreachable("Unknown icmp predicate!");
   3172     case ICMP_EQ: case ICMP_NE:
   3173     case ICMP_SGT: case ICMP_SLT: case ICMP_SGE: case ICMP_SLE:
   3174        return pred;
   3175     case ICMP_UGT: return ICMP_SGT;
   3176     case ICMP_ULT: return ICMP_SLT;
   3177     case ICMP_UGE: return ICMP_SGE;
   3178     case ICMP_ULE: return ICMP_SLE;
   3179   }
   3180 }
   3181 
   3182 ICmpInst::Predicate ICmpInst::getUnsignedPredicate(Predicate pred) {
   3183   switch (pred) {
   3184     default: llvm_unreachable("Unknown icmp predicate!");
   3185     case ICMP_EQ: case ICMP_NE:
   3186     case ICMP_UGT: case ICMP_ULT: case ICMP_UGE: case ICMP_ULE:
   3187        return pred;
   3188     case ICMP_SGT: return ICMP_UGT;
   3189     case ICMP_SLT: return ICMP_ULT;
   3190     case ICMP_SGE: return ICMP_UGE;
   3191     case ICMP_SLE: return ICMP_ULE;
   3192   }
   3193 }
   3194 
   3195 /// Initialize a set of values that all satisfy the condition with C.
   3196 ///
   3197 ConstantRange
   3198 ICmpInst::makeConstantRange(Predicate pred, const APInt &C) {
   3199   APInt Lower(C);
   3200   APInt Upper(C);
   3201   uint32_t BitWidth = C.getBitWidth();
   3202   switch (pred) {
   3203   default: llvm_unreachable("Invalid ICmp opcode to ConstantRange ctor!");
   3204   case ICmpInst::ICMP_EQ: ++Upper; break;
   3205   case ICmpInst::ICMP_NE: ++Lower; break;
   3206   case ICmpInst::ICMP_ULT:
   3207     Lower = APInt::getMinValue(BitWidth);
   3208     // Check for an empty-set condition.
   3209     if (Lower == Upper)
   3210       return ConstantRange(BitWidth, /*isFullSet=*/false);
   3211     break;
   3212   case ICmpInst::ICMP_SLT:
   3213     Lower = APInt::getSignedMinValue(BitWidth);
   3214     // Check for an empty-set condition.
   3215     if (Lower == Upper)
   3216       return ConstantRange(BitWidth, /*isFullSet=*/false);
   3217     break;
   3218   case ICmpInst::ICMP_UGT:
   3219     ++Lower; Upper = APInt::getMinValue(BitWidth);        // Min = Next(Max)
   3220     // Check for an empty-set condition.
   3221     if (Lower == Upper)
   3222       return ConstantRange(BitWidth, /*isFullSet=*/false);
   3223     break;
   3224   case ICmpInst::ICMP_SGT:
   3225     ++Lower; Upper = APInt::getSignedMinValue(BitWidth);  // Min = Next(Max)
   3226     // Check for an empty-set condition.
   3227     if (Lower == Upper)
   3228       return ConstantRange(BitWidth, /*isFullSet=*/false);
   3229     break;
   3230   case ICmpInst::ICMP_ULE:
   3231     Lower = APInt::getMinValue(BitWidth); ++Upper;
   3232     // Check for a full-set condition.
   3233     if (Lower == Upper)
   3234       return ConstantRange(BitWidth, /*isFullSet=*/true);
   3235     break;
   3236   case ICmpInst::ICMP_SLE:
   3237     Lower = APInt::getSignedMinValue(BitWidth); ++Upper;
   3238     // Check for a full-set condition.
   3239     if (Lower == Upper)
   3240       return ConstantRange(BitWidth, /*isFullSet=*/true);
   3241     break;
   3242   case ICmpInst::ICMP_UGE:
   3243     Upper = APInt::getMinValue(BitWidth);        // Min = Next(Max)
   3244     // Check for a full-set condition.
   3245     if (Lower == Upper)
   3246       return ConstantRange(BitWidth, /*isFullSet=*/true);
   3247     break;
   3248   case ICmpInst::ICMP_SGE:
   3249     Upper = APInt::getSignedMinValue(BitWidth);  // Min = Next(Max)
   3250     // Check for a full-set condition.
   3251     if (Lower == Upper)
   3252       return ConstantRange(BitWidth, /*isFullSet=*/true);
   3253     break;
   3254   }
   3255   return ConstantRange(Lower, Upper);
   3256 }
   3257 
   3258 CmpInst::Predicate CmpInst::getSwappedPredicate(Predicate pred) {
   3259   switch (pred) {
   3260     default: llvm_unreachable("Unknown cmp predicate!");
   3261     case ICMP_EQ: case ICMP_NE:
   3262       return pred;
   3263     case ICMP_SGT: return ICMP_SLT;
   3264     case ICMP_SLT: return ICMP_SGT;
   3265     case ICMP_SGE: return ICMP_SLE;
   3266     case ICMP_SLE: return ICMP_SGE;
   3267     case ICMP_UGT: return ICMP_ULT;
   3268     case ICMP_ULT: return ICMP_UGT;
   3269     case ICMP_UGE: return ICMP_ULE;
   3270     case ICMP_ULE: return ICMP_UGE;
   3271 
   3272     case FCMP_FALSE: case FCMP_TRUE:
   3273     case FCMP_OEQ: case FCMP_ONE:
   3274     case FCMP_UEQ: case FCMP_UNE:
   3275     case FCMP_ORD: case FCMP_UNO:
   3276       return pred;
   3277     case FCMP_OGT: return FCMP_OLT;
   3278     case FCMP_OLT: return FCMP_OGT;
   3279     case FCMP_OGE: return FCMP_OLE;
   3280     case FCMP_OLE: return FCMP_OGE;
   3281     case FCMP_UGT: return FCMP_ULT;
   3282     case FCMP_ULT: return FCMP_UGT;
   3283     case FCMP_UGE: return FCMP_ULE;
   3284     case FCMP_ULE: return FCMP_UGE;
   3285   }
   3286 }
   3287 
   3288 bool CmpInst::isUnsigned(unsigned short predicate) {
   3289   switch (predicate) {
   3290     default: return false;
   3291     case ICmpInst::ICMP_ULT: case ICmpInst::ICMP_ULE: case ICmpInst::ICMP_UGT:
   3292     case ICmpInst::ICMP_UGE: return true;
   3293   }
   3294 }
   3295 
   3296 bool CmpInst::isSigned(unsigned short predicate) {
   3297   switch (predicate) {
   3298     default: return false;
   3299     case ICmpInst::ICMP_SLT: case ICmpInst::ICMP_SLE: case ICmpInst::ICMP_SGT:
   3300     case ICmpInst::ICMP_SGE: return true;
   3301   }
   3302 }
   3303 
   3304 bool CmpInst::isOrdered(unsigned short predicate) {
   3305   switch (predicate) {
   3306     default: return false;
   3307     case FCmpInst::FCMP_OEQ: case FCmpInst::FCMP_ONE: case FCmpInst::FCMP_OGT:
   3308     case FCmpInst::FCMP_OLT: case FCmpInst::FCMP_OGE: case FCmpInst::FCMP_OLE:
   3309     case FCmpInst::FCMP_ORD: return true;
   3310   }
   3311 }
   3312 
   3313 bool CmpInst::isUnordered(unsigned short predicate) {
   3314   switch (predicate) {
   3315     default: return false;
   3316     case FCmpInst::FCMP_UEQ: case FCmpInst::FCMP_UNE: case FCmpInst::FCMP_UGT:
   3317     case FCmpInst::FCMP_ULT: case FCmpInst::FCMP_UGE: case FCmpInst::FCMP_ULE:
   3318     case FCmpInst::FCMP_UNO: return true;
   3319   }
   3320 }
   3321 
   3322 bool CmpInst::isTrueWhenEqual(unsigned short predicate) {
   3323   switch(predicate) {
   3324     default: return false;
   3325     case ICMP_EQ:   case ICMP_UGE: case ICMP_ULE: case ICMP_SGE: case ICMP_SLE:
   3326     case FCMP_TRUE: case FCMP_UEQ: case FCMP_UGE: case FCMP_ULE: return true;
   3327   }
   3328 }
   3329 
   3330 bool CmpInst::isFalseWhenEqual(unsigned short predicate) {
   3331   switch(predicate) {
   3332   case ICMP_NE:    case ICMP_UGT: case ICMP_ULT: case ICMP_SGT: case ICMP_SLT:
   3333   case FCMP_FALSE: case FCMP_ONE: case FCMP_OGT: case FCMP_OLT: return true;
   3334   default: return false;
   3335   }
   3336 }
   3337 
   3338 
   3339 //===----------------------------------------------------------------------===//
   3340 //                        SwitchInst Implementation
   3341 //===----------------------------------------------------------------------===//
   3342 
   3343 void SwitchInst::init(Value *Value, BasicBlock *Default, unsigned NumReserved) {
   3344   assert(Value && Default && NumReserved);
   3345   ReservedSpace = NumReserved;
   3346   NumOperands = 2;
   3347   OperandList = allocHungoffUses(ReservedSpace);
   3348 
   3349   OperandList[0] = Value;
   3350   OperandList[1] = Default;
   3351 }
   3352 
   3353 /// SwitchInst ctor - Create a new switch instruction, specifying a value to
   3354 /// switch on and a default destination.  The number of additional cases can
   3355 /// be specified here to make memory allocation more efficient.  This
   3356 /// constructor can also autoinsert before another instruction.
   3357 SwitchInst::SwitchInst(Value *Value, BasicBlock *Default, unsigned NumCases,
   3358                        Instruction *InsertBefore)
   3359   : TerminatorInst(Type::getVoidTy(Value->getContext()), Instruction::Switch,
   3360                    nullptr, 0, InsertBefore) {
   3361   init(Value, Default, 2+NumCases*2);
   3362 }
   3363 
   3364 /// SwitchInst ctor - Create a new switch instruction, specifying a value to
   3365 /// switch on and a default destination.  The number of additional cases can
   3366 /// be specified here to make memory allocation more efficient.  This
   3367 /// constructor also autoinserts at the end of the specified BasicBlock.
   3368 SwitchInst::SwitchInst(Value *Value, BasicBlock *Default, unsigned NumCases,
   3369                        BasicBlock *InsertAtEnd)
   3370   : TerminatorInst(Type::getVoidTy(Value->getContext()), Instruction::Switch,
   3371                    nullptr, 0, InsertAtEnd) {
   3372   init(Value, Default, 2+NumCases*2);
   3373 }
   3374 
   3375 SwitchInst::SwitchInst(const SwitchInst &SI)
   3376   : TerminatorInst(SI.getType(), Instruction::Switch, nullptr, 0) {
   3377   init(SI.getCondition(), SI.getDefaultDest(), SI.getNumOperands());
   3378   NumOperands = SI.getNumOperands();
   3379   Use *OL = OperandList, *InOL = SI.OperandList;
   3380   for (unsigned i = 2, E = SI.getNumOperands(); i != E; i += 2) {
   3381     OL[i] = InOL[i];
   3382     OL[i+1] = InOL[i+1];
   3383   }
   3384   SubclassOptionalData = SI.SubclassOptionalData;
   3385 }
   3386 
   3387 SwitchInst::~SwitchInst() {
   3388   dropHungoffUses();
   3389 }
   3390 
   3391 
   3392 /// addCase - Add an entry to the switch instruction...
   3393 ///
   3394 void SwitchInst::addCase(ConstantInt *OnVal, BasicBlock *Dest) {
   3395   unsigned NewCaseIdx = getNumCases();
   3396   unsigned OpNo = NumOperands;
   3397   if (OpNo+2 > ReservedSpace)
   3398     growOperands();  // Get more space!
   3399   // Initialize some new operands.
   3400   assert(OpNo+1 < ReservedSpace && "Growing didn't work!");
   3401   NumOperands = OpNo+2;
   3402   CaseIt Case(this, NewCaseIdx);
   3403   Case.setValue(OnVal);
   3404   Case.setSuccessor(Dest);
   3405 }
   3406 
   3407 /// removeCase - This method removes the specified case and its successor
   3408 /// from the switch instruction.
   3409 void SwitchInst::removeCase(CaseIt i) {
   3410   unsigned idx = i.getCaseIndex();
   3411 
   3412   assert(2 + idx*2 < getNumOperands() && "Case index out of range!!!");
   3413 
   3414   unsigned NumOps = getNumOperands();
   3415   Use *OL = OperandList;
   3416 
   3417   // Overwrite this case with the end of the list.
   3418   if (2 + (idx + 1) * 2 != NumOps) {
   3419     OL[2 + idx * 2] = OL[NumOps - 2];
   3420     OL[2 + idx * 2 + 1] = OL[NumOps - 1];
   3421   }
   3422 
   3423   // Nuke the last value.
   3424   OL[NumOps-2].set(nullptr);
   3425   OL[NumOps-2+1].set(nullptr);
   3426   NumOperands = NumOps-2;
   3427 }
   3428 
   3429 /// growOperands - grow operands - This grows the operand list in response
   3430 /// to a push_back style of operation.  This grows the number of ops by 3 times.
   3431 ///
   3432 void SwitchInst::growOperands() {
   3433   unsigned e = getNumOperands();
   3434   unsigned NumOps = e*3;
   3435 
   3436   ReservedSpace = NumOps;
   3437   Use *NewOps = allocHungoffUses(NumOps);
   3438   Use *OldOps = OperandList;
   3439   for (unsigned i = 0; i != e; ++i) {
   3440       NewOps[i] = OldOps[i];
   3441   }
   3442   OperandList = NewOps;
   3443   Use::zap(OldOps, OldOps + e, true);
   3444 }
   3445 
   3446 
   3447 BasicBlock *SwitchInst::getSuccessorV(unsigned idx) const {
   3448   return getSuccessor(idx);
   3449 }
   3450 unsigned SwitchInst::getNumSuccessorsV() const {
   3451   return getNumSuccessors();
   3452 }
   3453 void SwitchInst::setSuccessorV(unsigned idx, BasicBlock *B) {
   3454   setSuccessor(idx, B);
   3455 }
   3456 
   3457 //===----------------------------------------------------------------------===//
   3458 //                        IndirectBrInst Implementation
   3459 //===----------------------------------------------------------------------===//
   3460 
   3461 void IndirectBrInst::init(Value *Address, unsigned NumDests) {
   3462   assert(Address && Address->getType()->isPointerTy() &&
   3463          "Address of indirectbr must be a pointer");
   3464   ReservedSpace = 1+NumDests;
   3465   NumOperands = 1;
   3466   OperandList = allocHungoffUses(ReservedSpace);
   3467 
   3468   OperandList[0] = Address;
   3469 }
   3470 
   3471 
   3472 /// growOperands - grow operands - This grows the operand list in response
   3473 /// to a push_back style of operation.  This grows the number of ops by 2 times.
   3474 ///
   3475 void IndirectBrInst::growOperands() {
   3476   unsigned e = getNumOperands();
   3477   unsigned NumOps = e*2;
   3478 
   3479   ReservedSpace = NumOps;
   3480   Use *NewOps = allocHungoffUses(NumOps);
   3481   Use *OldOps = OperandList;
   3482   for (unsigned i = 0; i != e; ++i)
   3483     NewOps[i] = OldOps[i];
   3484   OperandList = NewOps;
   3485   Use::zap(OldOps, OldOps + e, true);
   3486 }
   3487 
   3488 IndirectBrInst::IndirectBrInst(Value *Address, unsigned NumCases,
   3489                                Instruction *InsertBefore)
   3490 : TerminatorInst(Type::getVoidTy(Address->getContext()),Instruction::IndirectBr,
   3491                  nullptr, 0, InsertBefore) {
   3492   init(Address, NumCases);
   3493 }
   3494 
   3495 IndirectBrInst::IndirectBrInst(Value *Address, unsigned NumCases,
   3496                                BasicBlock *InsertAtEnd)
   3497 : TerminatorInst(Type::getVoidTy(Address->getContext()),Instruction::IndirectBr,
   3498                  nullptr, 0, InsertAtEnd) {
   3499   init(Address, NumCases);
   3500 }
   3501 
   3502 IndirectBrInst::IndirectBrInst(const IndirectBrInst &IBI)
   3503   : TerminatorInst(Type::getVoidTy(IBI.getContext()), Instruction::IndirectBr,
   3504                    allocHungoffUses(IBI.getNumOperands()),
   3505                    IBI.getNumOperands()) {
   3506   Use *OL = OperandList, *InOL = IBI.OperandList;
   3507   for (unsigned i = 0, E = IBI.getNumOperands(); i != E; ++i)
   3508     OL[i] = InOL[i];
   3509   SubclassOptionalData = IBI.SubclassOptionalData;
   3510 }
   3511 
   3512 IndirectBrInst::~IndirectBrInst() {
   3513   dropHungoffUses();
   3514 }
   3515 
   3516 /// addDestination - Add a destination.
   3517 ///
   3518 void IndirectBrInst::addDestination(BasicBlock *DestBB) {
   3519   unsigned OpNo = NumOperands;
   3520   if (OpNo+1 > ReservedSpace)
   3521     growOperands();  // Get more space!
   3522   // Initialize some new operands.
   3523   assert(OpNo < ReservedSpace && "Growing didn't work!");
   3524   NumOperands = OpNo+1;
   3525   OperandList[OpNo] = DestBB;
   3526 }
   3527 
   3528 /// removeDestination - This method removes the specified successor from the
   3529 /// indirectbr instruction.
   3530 void IndirectBrInst::removeDestination(unsigned idx) {
   3531   assert(idx < getNumOperands()-1 && "Successor index out of range!");
   3532 
   3533   unsigned NumOps = getNumOperands();
   3534   Use *OL = OperandList;
   3535 
   3536   // Replace this value with the last one.
   3537   OL[idx+1] = OL[NumOps-1];
   3538 
   3539   // Nuke the last value.
   3540   OL[NumOps-1].set(nullptr);
   3541   NumOperands = NumOps-1;
   3542 }
   3543 
   3544 BasicBlock *IndirectBrInst::getSuccessorV(unsigned idx) const {
   3545   return getSuccessor(idx);
   3546 }
   3547 unsigned IndirectBrInst::getNumSuccessorsV() const {
   3548   return getNumSuccessors();
   3549 }
   3550 void IndirectBrInst::setSuccessorV(unsigned idx, BasicBlock *B) {
   3551   setSuccessor(idx, B);
   3552 }
   3553 
   3554 //===----------------------------------------------------------------------===//
   3555 //                           clone_impl() implementations
   3556 //===----------------------------------------------------------------------===//
   3557 
   3558 // Define these methods here so vtables don't get emitted into every translation
   3559 // unit that uses these classes.
   3560 
   3561 GetElementPtrInst *GetElementPtrInst::clone_impl() const {
   3562   return new (getNumOperands()) GetElementPtrInst(*this);
   3563 }
   3564 
   3565 BinaryOperator *BinaryOperator::clone_impl() const {
   3566   return Create(getOpcode(), Op<0>(), Op<1>());
   3567 }
   3568 
   3569 FCmpInst* FCmpInst::clone_impl() const {
   3570   return new FCmpInst(getPredicate(), Op<0>(), Op<1>());
   3571 }
   3572 
   3573 ICmpInst* ICmpInst::clone_impl() const {
   3574   return new ICmpInst(getPredicate(), Op<0>(), Op<1>());
   3575 }
   3576 
   3577 ExtractValueInst *ExtractValueInst::clone_impl() const {
   3578   return new ExtractValueInst(*this);
   3579 }
   3580 
   3581 InsertValueInst *InsertValueInst::clone_impl() const {
   3582   return new InsertValueInst(*this);
   3583 }
   3584 
   3585 AllocaInst *AllocaInst::clone_impl() const {
   3586   AllocaInst *Result = new AllocaInst(getAllocatedType(),
   3587                                       (Value *)getOperand(0), getAlignment());
   3588   Result->setUsedWithInAlloca(isUsedWithInAlloca());
   3589   return Result;
   3590 }
   3591 
   3592 LoadInst *LoadInst::clone_impl() const {
   3593   return new LoadInst(getOperand(0), Twine(), isVolatile(),
   3594                       getAlignment(), getOrdering(), getSynchScope());
   3595 }
   3596 
   3597 StoreInst *StoreInst::clone_impl() const {
   3598   return new StoreInst(getOperand(0), getOperand(1), isVolatile(),
   3599                        getAlignment(), getOrdering(), getSynchScope());
   3600 
   3601 }
   3602 
   3603 AtomicCmpXchgInst *AtomicCmpXchgInst::clone_impl() const {
   3604   AtomicCmpXchgInst *Result =
   3605     new AtomicCmpXchgInst(getOperand(0), getOperand(1), getOperand(2),
   3606                           getSuccessOrdering(), getFailureOrdering(),
   3607                           getSynchScope());
   3608   Result->setVolatile(isVolatile());
   3609   Result->setWeak(isWeak());
   3610   return Result;
   3611 }
   3612 
   3613 AtomicRMWInst *AtomicRMWInst::clone_impl() const {
   3614   AtomicRMWInst *Result =
   3615     new AtomicRMWInst(getOperation(),getOperand(0), getOperand(1),
   3616                       getOrdering(), getSynchScope());
   3617   Result->setVolatile(isVolatile());
   3618   return Result;
   3619 }
   3620 
   3621 FenceInst *FenceInst::clone_impl() const {
   3622   return new FenceInst(getContext(), getOrdering(), getSynchScope());
   3623 }
   3624 
   3625 TruncInst *TruncInst::clone_impl() const {
   3626   return new TruncInst(getOperand(0), getType());
   3627 }
   3628 
   3629 ZExtInst *ZExtInst::clone_impl() const {
   3630   return new ZExtInst(getOperand(0), getType());
   3631 }
   3632 
   3633 SExtInst *SExtInst::clone_impl() const {
   3634   return new SExtInst(getOperand(0), getType());
   3635 }
   3636 
   3637 FPTruncInst *FPTruncInst::clone_impl() const {
   3638   return new FPTruncInst(getOperand(0), getType());
   3639 }
   3640 
   3641 FPExtInst *FPExtInst::clone_impl() const {
   3642   return new FPExtInst(getOperand(0), getType());
   3643 }
   3644 
   3645 UIToFPInst *UIToFPInst::clone_impl() const {
   3646   return new UIToFPInst(getOperand(0), getType());
   3647 }
   3648 
   3649 SIToFPInst *SIToFPInst::clone_impl() const {
   3650   return new SIToFPInst(getOperand(0), getType());
   3651 }
   3652 
   3653 FPToUIInst *FPToUIInst::clone_impl() const {
   3654   return new FPToUIInst(getOperand(0), getType());
   3655 }
   3656 
   3657 FPToSIInst *FPToSIInst::clone_impl() const {
   3658   return new FPToSIInst(getOperand(0), getType());
   3659 }
   3660 
   3661 PtrToIntInst *PtrToIntInst::clone_impl() const {
   3662   return new PtrToIntInst(getOperand(0), getType());
   3663 }
   3664 
   3665 IntToPtrInst *IntToPtrInst::clone_impl() const {
   3666   return new IntToPtrInst(getOperand(0), getType());
   3667 }
   3668 
   3669 BitCastInst *BitCastInst::clone_impl() const {
   3670   return new BitCastInst(getOperand(0), getType());
   3671 }
   3672 
   3673 AddrSpaceCastInst *AddrSpaceCastInst::clone_impl() const {
   3674   return new AddrSpaceCastInst(getOperand(0), getType());
   3675 }
   3676 
   3677 CallInst *CallInst::clone_impl() const {
   3678   return  new(getNumOperands()) CallInst(*this);
   3679 }
   3680 
   3681 SelectInst *SelectInst::clone_impl() const {
   3682   return SelectInst::Create(getOperand(0), getOperand(1), getOperand(2));
   3683 }
   3684 
   3685 VAArgInst *VAArgInst::clone_impl() const {
   3686   return new VAArgInst(getOperand(0), getType());
   3687 }
   3688 
   3689 ExtractElementInst *ExtractElementInst::clone_impl() const {
   3690   return ExtractElementInst::Create(getOperand(0), getOperand(1));
   3691 }
   3692 
   3693 InsertElementInst *InsertElementInst::clone_impl() const {
   3694   return InsertElementInst::Create(getOperand(0), getOperand(1), getOperand(2));
   3695 }
   3696 
   3697 ShuffleVectorInst *ShuffleVectorInst::clone_impl() const {
   3698   return new ShuffleVectorInst(getOperand(0), getOperand(1), getOperand(2));
   3699 }
   3700 
   3701 PHINode *PHINode::clone_impl() const {
   3702   return new PHINode(*this);
   3703 }
   3704 
   3705 LandingPadInst *LandingPadInst::clone_impl() const {
   3706   return new LandingPadInst(*this);
   3707 }
   3708 
   3709 ReturnInst *ReturnInst::clone_impl() const {
   3710   return new(getNumOperands()) ReturnInst(*this);
   3711 }
   3712 
   3713 BranchInst *BranchInst::clone_impl() const {
   3714   return new(getNumOperands()) BranchInst(*this);
   3715 }
   3716 
   3717 SwitchInst *SwitchInst::clone_impl() const {
   3718   return new SwitchInst(*this);
   3719 }
   3720 
   3721 IndirectBrInst *IndirectBrInst::clone_impl() const {
   3722   return new IndirectBrInst(*this);
   3723 }
   3724 
   3725 
   3726 InvokeInst *InvokeInst::clone_impl() const {
   3727   return new(getNumOperands()) InvokeInst(*this);
   3728 }
   3729 
   3730 ResumeInst *ResumeInst::clone_impl() const {
   3731   return new(1) ResumeInst(*this);
   3732 }
   3733 
   3734 UnreachableInst *UnreachableInst::clone_impl() const {
   3735   LLVMContext &Context = getContext();
   3736   return new UnreachableInst(Context);
   3737 }
   3738