void llvm::addLandingPadInfo(const LandingPadInst &I, MachineBasicBlock &MBB) {
MachineFunction &MF = *MBB.getParent();
if (const auto *PF = dyn_cast<Function>(
I.getParent()->getParent()->getPersonalityFn()->stripPointerCasts()))
MF.getMMI().addPersonality(PF);
if (I.isCleanup())
MF.addCleanup(&MBB);
// FIXME: New EH - Add the clauses in reverse order. This isn't 100% correct,
// but we need to do it this way because of how the DWARF EH emitter
// processes the clauses.
for (unsigned i = I.getNumClauses(); i != 0; --i) {
Value *Val = I.getClause(i - 1);
if (I.isCatch(i - 1)) {
MF.addCatchTypeInfo(&MBB,
dyn_cast<GlobalValue>(Val->stripPointerCasts()));
} else {
// Add filters in a list.
Constant *CVal = cast<Constant>(Val);
SmallVector<const GlobalValue *, 4> FilterList;
for (User::op_iterator II = CVal->op_begin(), IE = CVal->op_end();
II != IE; ++II)
FilterList.push_back(cast<GlobalValue>((*II)->stripPointerCasts()));
MF.addFilterTypeInfo(&MBB, FilterList);
}
}
}
/// Once all constants are read, this method bulk resolves any forward
/// references. The idea behind this is that we sometimes get constants (such
/// as large arrays) which reference *many* forward ref constants. Replacing
/// each of these causes a lot of thrashing when building/reuniquing the
/// constant. Instead of doing this, we look at all the uses and rewrite all
/// the place holders at once for any constant that uses a placeholder.
void BitcodeReaderValueList::resolveConstantForwardRefs() {
// Sort the values by-pointer so that they are efficient to look up with a
// binary search.
llvm::sort(ResolveConstants);
SmallVector<Constant *, 64> NewOps;
while (!ResolveConstants.empty()) {
Value *RealVal = operator[](ResolveConstants.back().second);
Constant *Placeholder = ResolveConstants.back().first;
ResolveConstants.pop_back();
// Loop over all users of the placeholder, updating them to reference the
// new value. If they reference more than one placeholder, update them all
// at once.
while (!Placeholder->use_empty()) {
auto UI = Placeholder->user_begin();
User *U = *UI;
// If the using object isn't uniqued, just update the operands. This
// handles instructions and initializers for global variables.
if (!isa<Constant>(U) || isa<GlobalValue>(U)) {
UI.getUse().set(RealVal);
continue;
}
// Otherwise, we have a constant that uses the placeholder. Replace that
// constant with a new constant that has *all* placeholder uses updated.
Constant *UserC = cast<Constant>(U);
for (User::op_iterator I = UserC->op_begin(), E = UserC->op_end(); I != E;
++I) {
Value *NewOp;
if (!isa<ConstantPlaceHolder>(*I)) {
// Not a placeholder reference.
NewOp = *I;
} else if (*I == Placeholder) {
// Common case is that it just references this one placeholder.
NewOp = RealVal;
} else {
// Otherwise, look up the placeholder in ResolveConstants.
ResolveConstantsTy::iterator It = llvm::lower_bound(
ResolveConstants,
std::pair<Constant *, unsigned>(cast<Constant>(*I), 0));
assert(It != ResolveConstants.end() && It->first == *I);
NewOp = operator[](It->second);
}
NewOps.push_back(cast<Constant>(NewOp));
}
// Make the new constant.
Constant *NewC;
if (ConstantArray *UserCA = dyn_cast<ConstantArray>(UserC)) {
NewC = ConstantArray::get(UserCA->getType(), NewOps);
} else if (ConstantStruct *UserCS = dyn_cast<ConstantStruct>(UserC)) {
NewC = ConstantStruct::get(UserCS->getType(), NewOps);
} else if (isa<ConstantVector>(UserC)) {
NewC = ConstantVector::get(NewOps);
} else {
assert(isa<ConstantExpr>(UserC) && "Must be a ConstantExpr.");
NewC = cast<ConstantExpr>(UserC)->getWithOperands(NewOps);
}
UserC->replaceAllUsesWith(NewC);
UserC->destroyConstant();
NewOps.clear();
}
// Update all ValueHandles, they should be the only users at this point.
Placeholder->replaceAllUsesWith(RealVal);
Placeholder->deleteValue();
}
}
