/// Given an RValue of aggregate type, compute the values of the elements by
/// emitting a series of tuple_element instructions.
static void getScalarizedElements(SILValue V,
SmallVectorImpl<SILValue> &ElementVals,
SILLocation Loc, SILBuilder &B) {
TupleType *TT = V->getType().castTo<TupleType>();
for (auto Index : indices(TT->getElements())) {
ElementVals.push_back(B.emitTupleExtract(Loc, V, Index));
}
}
/// Given an aggregate value and an access path, extract the value indicated by
/// the path.
static SILValue ExtractSubElement(SILValue Val, unsigned SubElementNumber,
SILBuilder &B, SILLocation Loc) {
SILType ValTy = Val.getType();
// Extract tuple elements.
if (auto TT = ValTy.getAs<TupleType>()) {
for (unsigned EltNo : indices(TT.getElementTypes())) {
// Keep track of what subelement is being referenced.
SILType EltTy = ValTy.getTupleElementType(EltNo);
unsigned NumSubElt = getNumSubElements(EltTy, B.getModule());
if (SubElementNumber < NumSubElt) {
Val = B.emitTupleExtract(Loc, Val, EltNo, EltTy);
return ExtractSubElement(Val, SubElementNumber, B, Loc);
}
SubElementNumber -= NumSubElt;
}
llvm_unreachable("Didn't find field");
}
// Extract struct elements.
if (auto *SD = getFullyReferenceableStruct(ValTy)) {
for (auto *D : SD->getStoredProperties()) {
auto fieldType = ValTy.getFieldType(D, B.getModule());
unsigned NumSubElt = getNumSubElements(fieldType, B.getModule());
if (SubElementNumber < NumSubElt) {
Val = B.emitStructExtract(Loc, Val, D);
return ExtractSubElement(Val, SubElementNumber, B, Loc);
}
SubElementNumber -= NumSubElt;
}
llvm_unreachable("Didn't find field");
}
// Otherwise, we're down to a scalar.
assert(SubElementNumber == 0 && "Miscalculation indexing subelements");
return Val;
}
