+FunctionPass *llvm::createDwarfEHPass(const TargetMachine *tm, bool fast) {
+ return new DwarfEHPrepare(tm, fast);
+}
+
+/// HasCatchAllInSelector - Return true if the intrinsic instruction has a
+/// catch-all.
+bool DwarfEHPrepare::HasCatchAllInSelector(IntrinsicInst *II) {
+ if (!EHCatchAllValue) return false;
+
+ unsigned ArgIdx = II->getNumArgOperands() - 1;
+ GlobalVariable *GV = dyn_cast<GlobalVariable>(II->getArgOperand(ArgIdx));
+ return GV == EHCatchAllValue;
+}
+
+/// FindAllCleanupSelectors - Find all eh.selector calls that are clean-ups.
+void DwarfEHPrepare::
+FindAllCleanupSelectors(SmallPtrSet<IntrinsicInst*, 32> &Sels,
+ SmallPtrSet<IntrinsicInst*, 32> &CatchAllSels) {
+ for (Value::use_iterator
+ I = SelectorIntrinsic->use_begin(),
+ E = SelectorIntrinsic->use_end(); I != E; ++I) {
+ IntrinsicInst *II = cast<IntrinsicInst>(*I);
+
+ if (II->getParent()->getParent() != F)
+ continue;
+
+ if (!HasCatchAllInSelector(II))
+ Sels.insert(II);
+ else
+ CatchAllSels.insert(II);
+ }
+}
+
+/// FindAllURoRInvokes - Find all URoR invokes in the function.
+void DwarfEHPrepare::
+FindAllURoRInvokes(SmallPtrSet<InvokeInst*, 32> &URoRInvokes) {
+ for (Value::use_iterator
+ I = URoR->use_begin(),
+ E = URoR->use_end(); I != E; ++I) {
+ if (InvokeInst *II = dyn_cast<InvokeInst>(*I))
+ URoRInvokes.insert(II);
+ }
+}
+
+/// CleanupSelectors - Any remaining eh.selector intrinsic calls which still use
+/// the "llvm.eh.catch.all.value" call need to convert to using its
+/// initializer instead.
+bool DwarfEHPrepare::CleanupSelectors(SmallPtrSet<IntrinsicInst*, 32> &Sels) {
+ if (!EHCatchAllValue) return false;
+
+ if (!SelectorIntrinsic) {
+ SelectorIntrinsic =
+ Intrinsic::getDeclaration(F->getParent(), Intrinsic::eh_selector);
+ if (!SelectorIntrinsic) return false;
+ }
+
+ bool Changed = false;
+ for (SmallPtrSet<IntrinsicInst*, 32>::iterator
+ I = Sels.begin(), E = Sels.end(); I != E; ++I) {
+ IntrinsicInst *Sel = *I;
+
+ // Index of the "llvm.eh.catch.all.value" variable.
+ unsigned OpIdx = Sel->getNumArgOperands() - 1;
+ GlobalVariable *GV = dyn_cast<GlobalVariable>(Sel->getArgOperand(OpIdx));
+ if (GV != EHCatchAllValue) continue;
+ Sel->setArgOperand(OpIdx, EHCatchAllValue->getInitializer());
+ Changed = true;
+ }
+
+ return Changed;
+}
+
+/// FindSelectorAndURoR - Find the eh.selector call associated with the
+/// eh.exception call. And indicate if there is a URoR "invoke" associated with
+/// the eh.exception call. This recursively looks past instructions which don't
+/// change the EH pointer value, like casts or PHI nodes.
+bool
+DwarfEHPrepare::FindSelectorAndURoR(Instruction *Inst, bool &URoRInvoke,
+ SmallPtrSet<IntrinsicInst*, 8> &SelCalls) {
+ SmallPtrSet<PHINode*, 32> SeenPHIs;
+ bool Changed = false;
+
+ restart:
+ for (Value::use_iterator
+ I = Inst->use_begin(), E = Inst->use_end(); I != E; ++I) {
+ Instruction *II = dyn_cast<Instruction>(*I);
+ if (!II || II->getParent()->getParent() != F) continue;
+
+ if (IntrinsicInst *Sel = dyn_cast<IntrinsicInst>(II)) {
+ if (Sel->getIntrinsicID() == Intrinsic::eh_selector)
+ SelCalls.insert(Sel);
+ } else if (InvokeInst *Invoke = dyn_cast<InvokeInst>(II)) {
+ if (Invoke->getCalledFunction() == URoR)
+ URoRInvoke = true;
+ } else if (CastInst *CI = dyn_cast<CastInst>(II)) {
+ Changed |= FindSelectorAndURoR(CI, URoRInvoke, SelCalls);
+ } else if (StoreInst *SI = dyn_cast<StoreInst>(II)) {
+ if (!PromoteStoreInst(SI)) continue;
+ Changed = true;
+ SeenPHIs.clear();
+ goto restart; // Uses may have changed, restart loop.
+ } else if (PHINode *PN = dyn_cast<PHINode>(II)) {
+ if (SeenPHIs.insert(PN))
+ // Don't process a PHI node more than once.
+ Changed |= FindSelectorAndURoR(PN, URoRInvoke, SelCalls);
+ }
+ }
+
+ return Changed;
+}
+
+/// HandleURoRInvokes - Handle invokes of "_Unwind_Resume_or_Rethrow" calls. The
+/// "unwind" part of these invokes jump to a landing pad within the current
+/// function. This is a candidate to merge the selector associated with the URoR
+/// invoke with the one from the URoR's landing pad.
+bool DwarfEHPrepare::HandleURoRInvokes() {
+ if (!EHCatchAllValue) {
+ EHCatchAllValue =
+ F->getParent()->getNamedGlobal("llvm.eh.catch.all.value");
+ if (!EHCatchAllValue) return false;
+ }
+
+ if (!SelectorIntrinsic) {
+ SelectorIntrinsic =
+ Intrinsic::getDeclaration(F->getParent(), Intrinsic::eh_selector);
+ if (!SelectorIntrinsic) return false;
+ }
+
+ SmallPtrSet<IntrinsicInst*, 32> Sels;
+ SmallPtrSet<IntrinsicInst*, 32> CatchAllSels;
+ FindAllCleanupSelectors(Sels, CatchAllSels);
+
+ if (!DT)
+ // We require DominatorTree information.
+ return CleanupSelectors(CatchAllSels);
+
+ if (!URoR) {
+ URoR = F->getParent()->getFunction("_Unwind_Resume_or_Rethrow");
+ if (!URoR) return CleanupSelectors(CatchAllSels);
+ }
+
+ SmallPtrSet<InvokeInst*, 32> URoRInvokes;
+ FindAllURoRInvokes(URoRInvokes);
+
+ SmallPtrSet<IntrinsicInst*, 32> SelsToConvert;
+
+ for (SmallPtrSet<IntrinsicInst*, 32>::iterator
+ SI = Sels.begin(), SE = Sels.end(); SI != SE; ++SI) {
+ const BasicBlock *SelBB = (*SI)->getParent();
+ for (SmallPtrSet<InvokeInst*, 32>::iterator
+ UI = URoRInvokes.begin(), UE = URoRInvokes.end(); UI != UE; ++UI) {
+ const BasicBlock *URoRBB = (*UI)->getParent();
+ if (DT->dominates(SelBB, URoRBB)) {
+ SelsToConvert.insert(*SI);
+ break;
+ }
+ }
+ }
+
+ bool Changed = false;
+
+ if (Sels.size() != SelsToConvert.size()) {
+ // If we haven't been able to convert all of the clean-up selectors, then
+ // loop through the slow way to see if they still need to be converted.
+ if (!ExceptionValueIntrinsic) {
+ ExceptionValueIntrinsic =
+ Intrinsic::getDeclaration(F->getParent(), Intrinsic::eh_exception);
+ if (!ExceptionValueIntrinsic)
+ return CleanupSelectors(CatchAllSels);
+ }
+
+ for (Value::use_iterator
+ I = ExceptionValueIntrinsic->use_begin(),
+ E = ExceptionValueIntrinsic->use_end(); I != E; ++I) {
+ IntrinsicInst *EHPtr = dyn_cast<IntrinsicInst>(*I);
+ if (!EHPtr || EHPtr->getParent()->getParent() != F) continue;
+
+ Changed |= PromoteEHPtrStore(EHPtr);
+
+ bool URoRInvoke = false;
+ SmallPtrSet<IntrinsicInst*, 8> SelCalls;
+ Changed |= FindSelectorAndURoR(EHPtr, URoRInvoke, SelCalls);
+
+ if (URoRInvoke) {
+ // This EH pointer is being used by an invoke of an URoR instruction and
+ // an eh.selector intrinsic call. If the eh.selector is a 'clean-up', we
+ // need to convert it to a 'catch-all'.
+ for (SmallPtrSet<IntrinsicInst*, 8>::iterator
+ SI = SelCalls.begin(), SE = SelCalls.end(); SI != SE; ++SI)
+ if (!HasCatchAllInSelector(*SI))
+ SelsToConvert.insert(*SI);
+ }
+ }
+ }
+
+ if (!SelsToConvert.empty()) {
+ // Convert all clean-up eh.selectors, which are associated with "invokes" of
+ // URoR calls, into catch-all eh.selectors.
+ Changed = true;
+
+ for (SmallPtrSet<IntrinsicInst*, 8>::iterator
+ SI = SelsToConvert.begin(), SE = SelsToConvert.end();
+ SI != SE; ++SI) {
+ IntrinsicInst *II = *SI;
+
+ // Use the exception object pointer and the personality function
+ // from the original selector.
+ CallSite CS(II);
+ IntrinsicInst::op_iterator I = CS.arg_begin();
+ IntrinsicInst::op_iterator E = CS.arg_end();
+ IntrinsicInst::op_iterator B = prior(E);
+
+ // Exclude last argument if it is an integer.
+ if (isa<ConstantInt>(B)) E = B;
+
+ // Add exception object pointer (front).
+ // Add personality function (next).
+ // Add in any filter IDs (rest).
+ SmallVector<Value*, 8> Args(I, E);
+
+ Args.push_back(EHCatchAllValue->getInitializer()); // Catch-all indicator.
+
+ CallInst *NewSelector =
+ CallInst::Create(SelectorIntrinsic, Args.begin(), Args.end(),
+ "eh.sel.catch.all", II);
+
+ NewSelector->setTailCall(II->isTailCall());
+ NewSelector->setAttributes(II->getAttributes());
+ NewSelector->setCallingConv(II->getCallingConv());
+
+ II->replaceAllUsesWith(NewSelector);
+ II->eraseFromParent();
+ }
+ }
+
+ Changed |= CleanupSelectors(CatchAllSels);
+ return Changed;