DefinedOrUnknownSVal TypedValueRegion::getExtent(SValBuilder &svalBuilder) const {
ASTContext &Ctx = svalBuilder.getContext();
QualType T = getDesugaredValueType(Ctx);
if (isa<VariableArrayType>(T))
return nonloc::SymbolVal(svalBuilder.getSymbolManager().getExtentSymbol(this));
if (isa<IncompleteArrayType>(T))
return UnknownVal();
CharUnits size = Ctx.getTypeSizeInChars(T);
QualType sizeTy = svalBuilder.getArrayIndexType();
return svalBuilder.makeIntVal(size.getQuantity(), sizeTy);
}
DefinedOrUnknownSVal FieldRegion::getExtent(SValBuilder &svalBuilder) const {
DefinedOrUnknownSVal Extent = DeclRegion::getExtent(svalBuilder);
// A zero-length array at the end of a struct often stands for dynamically-
// allocated extra memory.
if (Extent.isZeroConstant()) {
QualType T = getDesugaredValueType(svalBuilder.getContext());
if (isa<ConstantArrayType>(T))
return UnknownVal();
}
return Extent;
}
/// Compute a raw byte offset from a base region. Used for array bounds
/// checking.
RegionRawOffsetV2 RegionRawOffsetV2::computeOffset(ProgramStateRef state,
SValBuilder &svalBuilder,
SVal location)
{
const MemRegion *region = location.getAsRegion();
SVal offset = UndefinedVal();
while (region) {
switch (region->getKind()) {
default: {
if (const SubRegion *subReg = dyn_cast<SubRegion>(region)) {
offset = getValue(offset, svalBuilder);
if (!offset.isUnknownOrUndef())
return RegionRawOffsetV2(subReg, offset);
}
return RegionRawOffsetV2();
}
case MemRegion::ElementRegionKind: {
const ElementRegion *elemReg = cast<ElementRegion>(region);
SVal index = elemReg->getIndex();
if (!isa<NonLoc>(index))
return RegionRawOffsetV2();
QualType elemType = elemReg->getElementType();
// If the element is an incomplete type, go no further.
ASTContext &astContext = svalBuilder.getContext();
if (!IsCompleteType(astContext, elemType))
return RegionRawOffsetV2();
// Update the offset.
offset = addValue(state,
getValue(offset, svalBuilder),
scaleValue(state,
cast<NonLoc>(index),
astContext.getTypeSizeInChars(elemType),
svalBuilder),
svalBuilder);
if (offset.isUnknownOrUndef())
return RegionRawOffsetV2();
region = elemReg->getSuperRegion();
continue;
}
}
}
return RegionRawOffsetV2();
}
