lib/VMCore/iMemory.cpp

   1 //===-- iMemory.cpp - Implement Memory instructions --------------*- C++ -*--=//
   2 //
   3 // This file implements the various memory related classes defined in iMemory.h
   4 //
   5 //===----------------------------------------------------------------------===//
   6
   7 #include "llvm/iMemory.h"
   8 #include "llvm/Constants.h"
   9 #include "llvm/DerivedTypes.h"
  10
  11 static inline const Type *checkType(const Type *Ty) {
  12   assert(Ty && "Invalid indices for type!");
  13   return Ty;
  14 }
  15
  16 AllocationInst::AllocationInst(const Type *Ty, Value *ArraySize, unsigned iTy,
  17                                const std::string &Name)
  18   : Instruction(Ty, iTy, Name) {
  19   assert(isa<PointerType>(Ty) && "Can't allocate a non pointer type!");
  20
  21   // ArraySize defaults to 1.
  22   if (!ArraySize) ArraySize = ConstantUInt::get(Type::UIntTy, 1);
  23
  24   Operands.reserve(1);
  25   assert(ArraySize->getType() == Type::UIntTy &&
  26          "Malloc/Allocation array size != UIntTy!");
  27
  28   Operands.push_back(Use(ArraySize, this));
  29 }
  30
  31 bool AllocationInst::isArrayAllocation() const {
  32   return getNumOperands() == 1 &&
  33          getOperand(0) != ConstantUInt::get(Type::UIntTy, 1);
  34 }
  35
  36 const Type *AllocationInst::getAllocatedType() const {
  37   return getType()->getElementType();
  38 }
  39
  40
  41 //===----------------------------------------------------------------------===//
  42 //                           LoadInst Implementation
  43 //===----------------------------------------------------------------------===//
  44
  45 LoadInst::LoadInst(Value *Ptr, const std::string &Name)
  46   : Instruction(cast<PointerType>(Ptr->getType())->getElementType(),
  47                 Load, Name) {
  48   Operands.reserve(1);
  49   Operands.push_back(Use(Ptr, this));
  50 }
  51
  52
  53 //===----------------------------------------------------------------------===//
  54 //                           StoreInst Implementation
  55 //===----------------------------------------------------------------------===//
  56
  57 StoreInst::StoreInst(Value *Val, Value *Ptr)
  58   : Instruction(Type::VoidTy, Store, "") {
  59
  60   Operands.reserve(2);
  61   Operands.push_back(Use(Val, this));
  62   Operands.push_back(Use(Ptr, this));
  63 }
  64
  65
  66 //===----------------------------------------------------------------------===//
  67 //                       GetElementPtrInst Implementation
  68 //===----------------------------------------------------------------------===//
  69
  70 GetElementPtrInst::GetElementPtrInst(Value *Ptr, const std::vector<Value*> &Idx,
  71                                      const std::string &Name)
  72   : Instruction(PointerType::get(checkType(getIndexedType(Ptr->getType(),
  73                                                             Idx, true))),
  74                   GetElementPtr, Name) {
  75   assert(getIndexedType(Ptr->getType(), Idx, true) && "gep operands invalid!");
  76   Operands.reserve(1+Idx.size());
  77   Operands.push_back(Use(Ptr, this));
  78
  79   for (unsigned i = 0, E = Idx.size(); i != E; ++i)
  80     Operands.push_back(Use(Idx[i], this));
  81 }
  82
  83 // getIndexedType - Returns the type of the element that would be loaded with
  84 // a load instruction with the specified parameters.
  85 //
  86 // A null type is returned if the indices are invalid for the specified
  87 // pointer type.
  88 //
  89 const Type* GetElementPtrInst::getIndexedType(const Type *Ptr,
  90                                               const std::vector<Value*> &Idx,
  91                                               bool AllowCompositeLeaf) {
  92   if (!isa<PointerType>(Ptr)) return 0;   // Type isn't a pointer type!
  93
  94   // Handle the special case of the empty set index set...
  95   if (Idx.empty()) return cast<PointerType>(Ptr)->getElementType();
  96
  97   unsigned CurIDX = 0;
  98   while (const CompositeType *CT = dyn_cast<CompositeType>(Ptr)) {
  99     if (Idx.size() == CurIDX) {
 100       if (AllowCompositeLeaf || CT->isFirstClassType()) return Ptr;
 101       return 0;   // Can't load a whole structure or array!?!?
 102     }
 103
 104     Value *Index = Idx[CurIDX++];
 105     if (!CT->indexValid(Index)) return 0;
 106     Ptr = CT->getTypeAtIndex(Index);
 107   }
 108   return CurIDX == Idx.size() ? Ptr : 0;
 109 }
 110
 111
 112 //===----------------------------------------------------------------------===//
 113 //                             FreeInst Implementation
 114 //===----------------------------------------------------------------------===//
 115
 116 FreeInst::FreeInst(Value *Ptr) : Instruction(Type::VoidTy, Free, "") {
 117   assert(isa<PointerType>(Ptr->getType()) && "Can't free nonpointer!");
 118   Operands.reserve(1);
 119   Operands.push_back(Use(Ptr, this));
 120 }
 121