本文整理汇总了C++中TargetData::getTypeSize方法的典型用法代码示例。如果您正苦于以下问题:C++ TargetData::getTypeSize方法的具体用法?C++ TargetData::getTypeSize怎么用?C++ TargetData::getTypeSize使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类TargetData
的用法示例。
在下文中一共展示了TargetData::getTypeSize方法的5个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: MallocConvertibleToType
// Peephole Malloc instructions: we take a look at the use chain of the
// malloc instruction, and try to find out if the following conditions hold:
// 1. The malloc is of the form: 'malloc [sbyte], uint <constant>'
// 2. The only users of the malloc are cast & add instructions
// 3. Of the cast instructions, there is only one destination pointer type
// [RTy] where the size of the pointed to object is equal to the number
// of bytes allocated.
//
// If these conditions hold, we convert the malloc to allocate an [RTy]
// element. TODO: This comment is out of date WRT arrays
//
static bool MallocConvertibleToType(MallocInst *MI, const Type *Ty,
ValueTypeCache &CTMap,
const TargetData &TD) {
if (!isa<PointerType>(Ty)) return false; // Malloc always returns pointers
// Deal with the type to allocate, not the pointer type...
Ty = cast<PointerType>(Ty)->getElementType();
if (!Ty->isSized()) return false; // Can only alloc something with a size
// Analyze the number of bytes allocated...
ExprType Expr = ClassifyExpr(MI->getArraySize());
// Get information about the base datatype being allocated, before & after
int ReqTypeSize = TD.getTypeSize(Ty);
if (ReqTypeSize == 0) return false;
unsigned OldTypeSize = TD.getTypeSize(MI->getType()->getElementType());
// Must have a scale or offset to analyze it...
if (!Expr.Offset && !Expr.Scale && OldTypeSize == 1) return false;
// Get the offset and scale of the allocation...
int64_t OffsetVal = Expr.Offset ? getConstantValue(Expr.Offset) : 0;
int64_t ScaleVal = Expr.Scale ? getConstantValue(Expr.Scale) :(Expr.Var != 0);
// The old type might not be of unit size, take old size into consideration
// here...
int64_t Offset = OffsetVal * OldTypeSize;
int64_t Scale = ScaleVal * OldTypeSize;
// In order to be successful, both the scale and the offset must be a multiple
// of the requested data type's size.
//
if (Offset/ReqTypeSize*ReqTypeSize != Offset ||
Scale/ReqTypeSize*ReqTypeSize != Scale)
return false; // Nope.
return true;
}
示例2: IsConstantOffsetFromGlobal
/// IsConstantOffsetFromGlobal - If this constant is actually a constant offset
/// from a global, return the global and the constant. Because of
/// constantexprs, this function is recursive.
static bool IsConstantOffsetFromGlobal(Constant *C, GlobalValue *&GV,
int64_t &Offset, const TargetData &TD) {
// Trivial case, constant is the global.
if ((GV = dyn_cast<GlobalValue>(C))) {
Offset = 0;
return true;
}
// Otherwise, if this isn't a constant expr, bail out.
ConstantExpr *CE = dyn_cast<ConstantExpr>(C);
if (!CE) return false;
// Look through ptr->int and ptr->ptr casts.
if (CE->getOpcode() == Instruction::PtrToInt ||
CE->getOpcode() == Instruction::BitCast)
return IsConstantOffsetFromGlobal(CE->getOperand(0), GV, Offset, TD);
// i32* getelementptr ([5 x i32]* @a, i32 0, i32 5)
if (CE->getOpcode() == Instruction::GetElementPtr) {
// Cannot compute this if the element type of the pointer is missing size
// info.
if (!cast<PointerType>(CE->getOperand(0)->getType())->getElementType()->isSized())
return false;
// If the base isn't a global+constant, we aren't either.
if (!IsConstantOffsetFromGlobal(CE->getOperand(0), GV, Offset, TD))
return false;
// Otherwise, add any offset that our operands provide.
gep_type_iterator GTI = gep_type_begin(CE);
for (unsigned i = 1, e = CE->getNumOperands(); i != e; ++i, ++GTI) {
ConstantInt *CI = dyn_cast<ConstantInt>(CE->getOperand(i));
if (!CI) return false; // Index isn't a simple constant?
if (CI->getZExtValue() == 0) continue; // Not adding anything.
if (const StructType *ST = dyn_cast<StructType>(*GTI)) {
// N = N + Offset
Offset += TD.getStructLayout(ST)->getElementOffset(CI->getZExtValue());
} else {
const SequentialType *SQT = cast<SequentialType>(*GTI);
Offset += TD.getTypeSize(SQT->getElementType())*CI->getSExtValue();
}
}
return true;
}
return false;
}
示例3: ConvertOperandToType
//.........这里部分代码省略.........
const Type *ValTy = cast<PointerType>(NewTy)->getElementType();
Value *SrcPtr = NewVal;
if (isa<StructType>(ValTy)) {
std::vector<Value*> Indices;
Indices.push_back(Constant::getNullValue(Type::UIntTy));
unsigned Offset = 0;
ValTy = getStructOffsetType(ValTy, Offset, Indices, TD, false);
assert(Offset == 0 && ValTy);
// Insert the GEP instruction before this store.
SrcPtr = new GetElementPtrInst(SrcPtr, Indices,
SrcPtr->getName()+".idx", I);
}
Res = new StoreInst(Constant::getNullValue(ValTy), SrcPtr);
VMC.ExprMap[I] = Res;
Res->setOperand(0, ConvertExpressionToType(I->getOperand(0),
ValTy, VMC, TD));
}
break;
}
case Instruction::GetElementPtr: {
// Convert a one index getelementptr into just about anything that is
// desired.
//
BasicBlock::iterator It = I;
const Type *OldElTy = cast<PointerType>(I->getType())->getElementType();
unsigned DataSize = TD.getTypeSize(OldElTy);
Value *Index = I->getOperand(1);
if (DataSize != 1) {
// Insert a multiply of the old element type is not a unit size...
Value *CST;
if (Index->getType()->isSigned())
CST = ConstantSInt::get(Index->getType(), DataSize);
else
CST = ConstantUInt::get(Index->getType(), DataSize);
Index = BinaryOperator::create(Instruction::Mul, Index, CST, "scale", It);
}
// Perform the conversion now...
//
std::vector<Value*> Indices;
const Type *ElTy = ConvertibleToGEP(NewVal->getType(),Index,Indices,TD,&It);
assert(ElTy != 0 && "GEP Conversion Failure!");
Res = new GetElementPtrInst(NewVal, Indices, Name);
assert(Res->getType() == PointerType::get(ElTy) &&
"ConvertibleToGet failed!");
}
#if 0
if (I->getType() == PointerType::get(Type::SByteTy)) {
// Convert a getelementptr sbyte * %reg111, uint 16 freely back to
// anything that is a pointer type...
//
BasicBlock::iterator It = I;
// Check to see if the second argument is an expression that can
// be converted to the appropriate size... if so, allow it.
//
示例4: OperandConvertibleToType
//.........这里部分代码省略.........
}
case Instruction::Shr:
if (Ty->isSigned() != V->getType()->isSigned()) return false;
// FALL THROUGH
case Instruction::Shl:
if (I->getOperand(1) == V) return false; // Cannot change shift amount type
if (!Ty->isInteger()) return false;
return ValueConvertibleToType(I, Ty, CTMap, TD);
case Instruction::Free:
assert(I->getOperand(0) == V);
return isa<PointerType>(Ty); // Free can free any pointer type!
case Instruction::Load:
// Cannot convert the types of any subscripts...
if (I->getOperand(0) != V) return false;
if (const PointerType *PT = dyn_cast<PointerType>(Ty)) {
LoadInst *LI = cast<LoadInst>(I);
const Type *LoadedTy = PT->getElementType();
// They could be loading the first element of a composite type...
if (const CompositeType *CT = dyn_cast<CompositeType>(LoadedTy)) {
unsigned Offset = 0; // No offset, get first leaf.
std::vector<Value*> Indices; // Discarded...
LoadedTy = getStructOffsetType(CT, Offset, Indices, TD, false);
assert(Offset == 0 && "Offset changed from zero???");
}
if (!LoadedTy->isFirstClassType())
return false;
if (TD.getTypeSize(LoadedTy) != TD.getTypeSize(LI->getType()))
return false;
return ValueConvertibleToType(LI, LoadedTy, CTMap, TD);
}
return false;
case Instruction::Store: {
StoreInst *SI = cast<StoreInst>(I);
if (V == I->getOperand(0)) {
ValueTypeCache::iterator CTMI = CTMap.find(I->getOperand(1));
if (CTMI != CTMap.end()) { // Operand #1 is in the table already?
// If so, check to see if it's Ty*, or, more importantly, if it is a
// pointer to a structure where the first element is a Ty... this code
// is necessary because we might be trying to change the source and
// destination type of the store (they might be related) and the dest
// pointer type might be a pointer to structure. Below we allow pointer
// to structures where the 0th element is compatible with the value,
// now we have to support the symmetrical part of this.
//
const Type *ElTy = cast<PointerType>(CTMI->second)->getElementType();
// Already a pointer to what we want? Trivially accept...
if (ElTy == Ty) return true;
// Tricky case now, if the destination is a pointer to structure,
// obviously the source is not allowed to be a structure (cannot copy
// a whole structure at a time), so the level raiser must be trying to
// store into the first field. Check for this and allow it now:
//
if (const StructType *SElTy = dyn_cast<StructType>(ElTy)) {
unsigned Offset = 0;
示例5: ExpressionConvertibleToType
//.........这里部分代码省略.........
//
GetElementPtrInst *GEP = cast<GetElementPtrInst>(I);
const PointerType *PTy = dyn_cast<PointerType>(Ty);
if (!PTy) return false; // GEP must always return a pointer...
const Type *PVTy = PTy->getElementType();
// Check to see if there are zero elements that we can remove from the
// index array. If there are, check to see if removing them causes us to
// get to the right type...
//
std::vector<Value*> Indices(GEP->idx_begin(), GEP->idx_end());
const Type *BaseType = GEP->getPointerOperand()->getType();
const Type *ElTy = 0;
while (!Indices.empty() &&
Indices.back() == Constant::getNullValue(Indices.back()->getType())){
Indices.pop_back();
ElTy = GetElementPtrInst::getIndexedType(BaseType, Indices, true);
if (ElTy == PVTy)
break; // Found a match!!
ElTy = 0;
}
if (ElTy) break; // Found a number of zeros we can strip off!
// Otherwise, we can convert a GEP from one form to the other iff the
// current gep is of the form 'getelementptr sbyte*, long N
// and we could convert this to an appropriate GEP for the new type.
//
if (GEP->getNumOperands() == 2 &&
GEP->getType() == PointerType::get(Type::SByteTy)) {
// Do not Check to see if our incoming pointer can be converted
// to be a ptr to an array of the right type... because in more cases than
// not, it is simply not analyzable because of pointer/array
// discrepancies. To fix this, we will insert a cast before the GEP.
//
// Check to see if 'N' is an expression that can be converted to
// the appropriate size... if so, allow it.
//
std::vector<Value*> Indices;
const Type *ElTy = ConvertibleToGEP(PTy, I->getOperand(1), Indices, TD);
if (ElTy == PVTy) {
if (!ExpressionConvertibleToType(I->getOperand(0),
PointerType::get(ElTy), CTMap, TD))
return false; // Can't continue, ExConToTy might have polluted set!
break;
}
}
// Otherwise, it could be that we have something like this:
// getelementptr [[sbyte] *] * %reg115, long %reg138 ; [sbyte]**
// and want to convert it into something like this:
// getelemenptr [[int] *] * %reg115, long %reg138 ; [int]**
//
if (GEP->getNumOperands() == 2 &&
PTy->getElementType()->isSized() &&
TD.getTypeSize(PTy->getElementType()) ==
TD.getTypeSize(GEP->getType()->getElementType())) {
const PointerType *NewSrcTy = PointerType::get(PVTy);
if (!ExpressionConvertibleToType(I->getOperand(0), NewSrcTy, CTMap, TD))
return false;
break;
}
return false; // No match, maybe next time.
}
case Instruction::Call: {
if (isa<Function>(I->getOperand(0)))
return false; // Don't even try to change direct calls.
// If this is a function pointer, we can convert the return type if we can
// convert the source function pointer.
//
const PointerType *PT = cast<PointerType>(I->getOperand(0)->getType());
const FunctionType *FT = cast<FunctionType>(PT->getElementType());
std::vector<const Type *> ArgTys(FT->param_begin(), FT->param_end());
const FunctionType *NewTy =
FunctionType::get(Ty, ArgTys, FT->isVarArg());
if (!ExpressionConvertibleToType(I->getOperand(0),
PointerType::get(NewTy), CTMap, TD))
return false;
break;
}
default:
return false;
}
// Expressions are only convertible if all of the users of the expression can
// have this value converted. This makes use of the map to avoid infinite
// recursion.
//
for (Value::use_iterator It = I->use_begin(), E = I->use_end(); It != E; ++It)
if (!OperandConvertibleToType(*It, I, Ty, CTMap, TD))
return false;
return true;
}