SILValue BlockState::reduceValuesAtEndOfBlock(RLEContext &Ctx, LSLocation &L) {
// First, collect current available locations and their corresponding values
// into a map.
LSLocationValueMap Values;
LSLocationList Locs;
LSLocation::expand(L, &BB->getModule(), Locs, Ctx.getTE());
// Find the values that this basic block defines and the locations which
// we do not have a concrete value in the current basic block.
ValueTableMap &OTM = getForwardValOut();
for (unsigned i = 0; i < Locs.size(); ++i) {
Values[Locs[i]] = Ctx.getValue(OTM[Ctx.getLocationBit(Locs[i])]);
}
// Second, reduce the available values into a single SILValue we can use to
// forward.
SILValue TheForwardingValue;
TheForwardingValue = LSValue::reduce(L, &BB->getModule(), Values,
BB->getTerminator(), Ctx.getTE());
/// Return the forwarding value.
return TheForwardingValue;
}
BlockState::ValueState BlockState::getValueStateAtEndOfBlock(RLEContext &Ctx,
LSLocation &L) {
// Find number of covering value and concrete values for the locations
// expanded from the given location.
unsigned CSCount = 0, CTCount = 0;
LSLocationList Locs;
LSLocation::expand(L, &BB->getModule(), Locs, Ctx.getTE());
ValueTableMap &OTM = getForwardValOut();
for (auto &X : Locs) {
LSValue &V = Ctx.getValue(OTM[Ctx.getLocationBit(X)]);
if (V.isCoveringValue()) {
++CSCount;
continue;
}
++CTCount;
}
if (CSCount == Locs.size())
return ValueState::CoverValues;
if (CTCount == Locs.size())
return ValueState::ConcreteValues;
return ValueState::CoverAndConcreteValues;
}