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
   9 static inline const Type *checkType(const Type *Ty) {
  10   assert(Ty && "Invalid indices for type!");
  11   return Ty;
  12 }
  13
  14 //===----------------------------------------------------------------------===//
  15 //                        MemAccessInst Implementation
  16 //===----------------------------------------------------------------------===//
  17
  18 // getIndexedType - Returns the type of the element that would be loaded with
  19 // a load instruction with the specified parameters.
  20 //
  21 // A null type is returned if the indices are invalid for the specified
  22 // pointer type.
  23 //
  24 const Type* MemAccessInst::getIndexedType(const Type *Ptr,
  25                                           const std::vector<Value*> &Idx,
  26                                           bool AllowCompositeLeaf = false) {
  27   if (!Ptr->isPointerType()) return 0;   // Type isn't a pointer type!
  28
  29   // Handle the special case of the empty set index set...
  30   if (Idx.empty()) return cast<PointerType>(Ptr)->getElementType();
  31
  32   unsigned CurIDX = 0;
  33   while (const CompositeType *CT = dyn_cast<CompositeType>(Ptr)) {
  34     if (Idx.size() == CurIDX) {
  35       if (AllowCompositeLeaf || CT->isFirstClassType()) return Ptr;
  36       return 0;   // Can't load a whole structure or array!?!?
  37     }
  38
  39     Value *Index = Idx[CurIDX++];
  40     if (!CT->indexValid(Index)) return 0;
  41     Ptr = CT->getTypeAtIndex(Index);
  42   }
  43   return CurIDX == Idx.size() ? Ptr : 0;
  44 }
  45
  46
  47 //===----------------------------------------------------------------------===//
  48 //                           LoadInst Implementation
  49 //===----------------------------------------------------------------------===//
  50
  51 LoadInst::LoadInst(Value *Ptr, const std::vector<Value*> &Idx,
  52                    const std::string &Name = "")
  53   : MemAccessInst(checkType(getIndexedType(Ptr->getType(), Idx)), Load, Name) {
  54   assert(getIndexedType(Ptr->getType(), Idx) && "Load operands invalid!");
  55   Operands.reserve(1+Idx.size());
  56   Operands.push_back(Use(Ptr, this));
  57
  58   for (unsigned i = 0, E = Idx.size(); i != E; ++i)
  59     Operands.push_back(Use(Idx[i], this));
  60
  61 }
  62
  63 LoadInst::LoadInst(Value *Ptr, const std::string &Name = "")
  64   : MemAccessInst(cast<PointerType>(Ptr->getType())->getElementType(),
  65                   Load, Name) {
  66   Operands.reserve(1);
  67   Operands.push_back(Use(Ptr, this));
  68 }
  69
  70
  71 //===----------------------------------------------------------------------===//
  72 //                           StoreInst Implementation
  73 //===----------------------------------------------------------------------===//
  74
  75 StoreInst::StoreInst(Value *Val, Value *Ptr, const std::vector<Value*> &Idx,
  76                      const std::string &Name = "")
  77   : MemAccessInst(Type::VoidTy, Store, Name) {
  78   assert(getIndexedType(Ptr->getType(), Idx) && "Store operands invalid!");
  79
  80   Operands.reserve(2+Idx.size());
  81   Operands.push_back(Use(Val, this));
  82   Operands.push_back(Use(Ptr, this));
  83
  84   for (unsigned i = 0, E = Idx.size(); i != E; ++i)
  85     Operands.push_back(Use(Idx[i], this));
  86 }
  87
  88 StoreInst::StoreInst(Value *Val, Value *Ptr, const std::string &Name = "")
  89   : MemAccessInst(Type::VoidTy, Store, Name) {
  90
  91   Operands.reserve(2);
  92   Operands.push_back(Use(Val, this));
  93   Operands.push_back(Use(Ptr, this));
  94 }
  95
  96
  97 //===----------------------------------------------------------------------===//
  98 //                       GetElementPtrInst Implementation
  99 //===----------------------------------------------------------------------===//
 100
 101 GetElementPtrInst::GetElementPtrInst(Value *Ptr, const std::vector<Value*> &Idx,
 102                                      const std::string &Name = "")
 103   : MemAccessInst(PointerType::get(checkType(getIndexedType(Ptr->getType(),
 104                                                             Idx, true))),
 105                   GetElementPtr, Name) {
 106   assert(getIndexedType(Ptr->getType(), Idx, true) && "gep operands invalid!");
 107   Operands.reserve(1+Idx.size());
 108   Operands.push_back(Use(Ptr, this));
 109
 110   for (unsigned i = 0, E = Idx.size(); i != E; ++i)
 111     Operands.push_back(Use(Idx[i], this));
 112 }
 113
 114 bool GetElementPtrInst::isStructSelector() const {
 115   return ((PointerType*)Operands[0]->getType())->getElementType()->isStructType();
 116 }