void
CodeGenRegister::addSubRegsPreOrder(SetVector<CodeGenRegister*> &OSet) const {
assert(SubRegsComplete && "Must precompute sub-registers");
std::vector<Record*> Indices = TheDef->getValueAsListOfDefs("SubRegIndices");
for (unsigned i = 0, e = Indices.size(); i != e; ++i) {
CodeGenRegister *SR = SubRegs.find(Indices[i])->second;
if (OSet.insert(SR))
SR->addSubRegsPreOrder(OSet);
}
}
BitVector CodeGenRegBank::computeCoveredRegisters(ArrayRef<Record*> Regs) {
SetVector<const CodeGenRegister*> Set;
// First add Regs with all sub-registers.
for (unsigned i = 0, e = Regs.size(); i != e; ++i) {
CodeGenRegister *Reg = getReg(Regs[i]);
if (Set.insert(Reg))
// Reg is new, add all sub-registers.
// The pre-ordering is not important here.
Reg->addSubRegsPreOrder(Set, *this);
}
// Second, find all super-registers that are completely covered by the set.
for (unsigned i = 0; i != Set.size(); ++i) {
const CodeGenRegister::SuperRegList &SR = Set[i]->getSuperRegs();
for (unsigned j = 0, e = SR.size(); j != e; ++j) {
const CodeGenRegister *Super = SR[j];
if (!Super->CoveredBySubRegs || Set.count(Super))
continue;
// This new super-register is covered by its sub-registers.
bool AllSubsInSet = true;
const CodeGenRegister::SubRegMap &SRM = Super->getSubRegs();
for (CodeGenRegister::SubRegMap::const_iterator I = SRM.begin(),
E = SRM.end(); I != E; ++I)
if (!Set.count(I->second)) {
AllSubsInSet = false;
break;
}
// All sub-registers in Set, add Super as well.
// We will visit Super later to recheck its super-registers.
if (AllSubsInSet)
Set.insert(Super);
}
}
// Convert to BitVector.
BitVector BV(Registers.size() + 1);
for (unsigned i = 0, e = Set.size(); i != e; ++i)
BV.set(Set[i]->EnumValue);
return BV;
}
