diff options
| -rw-r--r-- | lib/VMCore/AutoUpgrade.cpp | 147 |
1 files changed, 113 insertions, 34 deletions
diff --git a/lib/VMCore/AutoUpgrade.cpp b/lib/VMCore/AutoUpgrade.cpp index 7b0b34ed89..2c327660d4 100644 --- a/lib/VMCore/AutoUpgrade.cpp +++ b/lib/VMCore/AutoUpgrade.cpp @@ -387,10 +387,9 @@ void llvm::UpgradeExceptionHandling(Module *M) { Type *SelTy = Type::getInt32Ty(Context); Type *LPadSlotTy = StructType::get(ExnTy, SelTy, NULL); - // This map stores the slots where the exception object and selector value are - // stored within a function. - SmallPtrSet<Instruction*, 32> DeadInsts; - DenseMap<Function*, std::pair<Value*, Value*> > FnToLPadSlotMap; + // This map links the invoke instruction with the eh.exception and eh.selector + // calls associated with it. + DenseMap<InvokeInst*, std::pair<Value*, Value*> > InvokeToIntrinsicsMap; for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) { Function &F = *I; @@ -401,47 +400,127 @@ void llvm::UpgradeExceptionHandling(Module *M) { InvokeInst *Inst = dyn_cast<InvokeInst>(BB->getTerminator()); if (!Inst) continue; BasicBlock *UnwindDest = Inst->getUnwindDest(); - if (UnwindDest->isLandingPad()) continue; // All ready converted. - - // Store the exception object and selector value in the entry block. - Value *ExnSlot = 0; - Value *SelSlot = 0; - if (!FnToLPadSlotMap[&F].first) { - BasicBlock *Entry = &F.front(); - ExnSlot = new AllocaInst(ExnTy, "exn", Entry->getTerminator()); - SelSlot = new AllocaInst(SelTy, "sel", Entry->getTerminator()); - FnToLPadSlotMap[&F] = std::make_pair(ExnSlot, SelSlot); - } else { - ExnSlot = FnToLPadSlotMap[&F].first; - SelSlot = FnToLPadSlotMap[&F].second; - } - - // We're in an unwind block. Try to find the eh.exception and eh.selector - // calls. - IRBuilder<> Builder(Context); - Builder.SetInsertPoint(UnwindDest, UnwindDest->getFirstNonPHI()); + if (UnwindDest->isLandingPad()) continue; // Already converted. SmallPtrSet<BasicBlock*, 8> Visited; CallInst *Exn = 0; CallInst *Sel = 0; FindExnAndSelIntrinsics(UnwindDest, Exn, Sel, Visited); assert(Exn && Sel && "Cannot find eh.exception and eh.selector calls!"); + InvokeToIntrinsicsMap[Inst] = std::make_pair(Exn, Sel); + } + } + + // This map stores the slots where the exception object and selector value are + // stored within a function. + DenseMap<Function*, std::pair<Value*, Value*> > FnToLPadSlotMap; + + // This maps the old intrinsic calls (eh.exception & eh.selector) to the new + // landingpad instruction(s). + DenseMap<std::pair<CallInst*, CallInst*>, + SmallVector<std::pair<Value*, Value*>, 8> > OldExnToNewExnMap; + + SmallPtrSet<Instruction*, 32> DeadInsts; + for (DenseMap<InvokeInst*, std::pair<Value*, Value*> >::iterator + I = InvokeToIntrinsicsMap.begin(), E = InvokeToIntrinsicsMap.end(); + I != E; ++I) { + InvokeInst *Invoke = I->first; + BasicBlock *UnwindDest = Invoke->getUnwindDest(); + Function *F = UnwindDest->getParent(); + std::pair<Value*, Value*> EHIntrinsics = I->second; + CallInst *Exn = cast<CallInst>(EHIntrinsics.first); + CallInst *Sel = cast<CallInst>(EHIntrinsics.second); + + // Store the exception object and selector value in the entry block. + Value *ExnSlot = 0; + Value *SelSlot = 0; + if (!FnToLPadSlotMap[F].first) { + BasicBlock *Entry = &F->front(); + ExnSlot = new AllocaInst(ExnTy, "exn", Entry->getTerminator()); + SelSlot = new AllocaInst(SelTy, "sel", Entry->getTerminator()); + FnToLPadSlotMap[F] = std::make_pair(ExnSlot, SelSlot); + } else { + ExnSlot = FnToLPadSlotMap[F].first; + SelSlot = FnToLPadSlotMap[F].second; + } - Value *PersFn = Sel->getArgOperand(1); - LandingPadInst *LPI = Builder.CreateLandingPad(LPadSlotTy, PersFn, 0); - Value *LPExn = Builder.CreateExtractValue(LPI, 0); - Value *LPSel = Builder.CreateExtractValue(LPI, 1); - Builder.CreateStore(LPExn, ExnSlot); - Builder.CreateStore(LPSel, SelSlot); + if (!UnwindDest->getSinglePredecessor()) { + // The unwind destination doesn't have a single predecessor. Create an + // unwind destination which has only one predecessor. + BasicBlock *NewBB = BasicBlock::Create(Context, "new.lpad", + UnwindDest->getParent()); + BranchInst::Create(UnwindDest, NewBB); + Invoke->setUnwindDest(NewBB); + + // Fix up any PHIs in the original unwind destination block. + for (BasicBlock::iterator + II = UnwindDest->begin(); isa<PHINode>(II); ++II) { + PHINode *PN = cast<PHINode>(II); + int Idx = PN->getBasicBlockIndex(Invoke->getParent()); + if (Idx == -1) continue; + PN->setIncomingBlock(Idx, NewBB); + } - TransferClausesToLandingPadInst(LPI, Sel); + UnwindDest = NewBB; + } - Exn->replaceAllUsesWith(LPExn); - Sel->replaceAllUsesWith(LPSel); + IRBuilder<> Builder(Context); + Builder.SetInsertPoint(UnwindDest, UnwindDest->getFirstInsertionPt()); - DeadInsts.insert(Exn); - DeadInsts.insert(Sel); + Value *PersFn = Sel->getArgOperand(1); + LandingPadInst *LPI = Builder.CreateLandingPad(LPadSlotTy, PersFn, 0); + Value *LPExn = Builder.CreateExtractValue(LPI, 0); + Value *LPSel = Builder.CreateExtractValue(LPI, 1); + Builder.CreateStore(LPExn, ExnSlot); + Builder.CreateStore(LPSel, SelSlot); + + TransferClausesToLandingPadInst(LPI, Sel); + + OldExnToNewExnMap[std::make_pair(Exn, Sel)]. + push_back(std::make_pair(LPExn, LPSel)); + + DeadInsts.insert(Exn); + DeadInsts.insert(Sel); + } + + // Replace the old intrinsic calls with the new (possibly PHI'ed) values. + for (DenseMap<std::pair<CallInst*, CallInst*>, + SmallVector<std::pair<Value*, Value*>, 8> >::iterator + I = OldExnToNewExnMap.begin(), E = OldExnToNewExnMap.end(); + I != E; ++I) { + std::pair<CallInst*, CallInst*> OldExnSel = I->first; + CallInst *Exn = OldExnSel.first; + CallInst *Sel = OldExnSel.second; + SmallVector<std::pair<Value*, Value*>, 8> &LPExnSel = I->second; + unsigned Size = LPExnSel.size(); + Value *LPExn = LPExnSel[0].first; + Value *LPSel = LPExnSel[0].second; + + if (Size != 1) { + BasicBlock *Parent = Exn->getParent(); + IRBuilder<> Builder(Context); + Builder.SetInsertPoint(Parent, Parent->getFirstInsertionPt()); + + PHINode *PN = Builder.CreatePHI(Exn->getType(), Size, "exn.phi"); + for (SmallVector<std::pair<Value*, Value*>, 8>::iterator + II = LPExnSel.begin(), IE = LPExnSel.end(); II != IE; ++II) + PN->addIncoming(II->first, cast<Instruction>(II->first)->getParent()); + + LPExn = PN; + + Parent = Sel->getParent(); + Builder.SetInsertPoint(Parent, Parent->getFirstInsertionPt()); + + PN = Builder.CreatePHI(Sel->getType(), Size, "sel.phi"); + for (SmallVector<std::pair<Value*, Value*>, 8>::iterator + II = LPExnSel.begin(), IE = LPExnSel.end(); II != IE; ++II) + PN->addIncoming(II->second, cast<Instruction>(II->second)->getParent()); + + LPSel = PN; } + + Exn->replaceAllUsesWith(LPExn); + Sel->replaceAllUsesWith(LPSel); } // Remove the dead instructions. |