- // If this is an MSVC-style personality function, we need to split the landing
- // pad into several BBs.
- const BasicBlock *LLVMBB = MBB->getBasicBlock();
- const LandingPadInst *LPadInst = LLVMBB->getLandingPadInst();
- MF->getMMI().addPersonality(
- MBB, cast<Function>(LPadInst->getPersonalityFn()->stripPointerCasts()));
- if (MF->getMMI().getPersonalityType() == EHPersonality::MSVC_Win64SEH) {
- // Make virtual registers and a series of labels that fill in values for the
- // clauses.
- auto &RI = MF->getRegInfo();
- FuncInfo->ExceptionSelectorVirtReg = RI.createVirtualRegister(PtrRC);
-
- // Get all invoke BBs that will unwind into the clause BBs.
- SmallVector<MachineBasicBlock *, 4> InvokeBBs(MBB->pred_begin(),
- MBB->pred_end());
-
- // Emit separate machine basic blocks with separate labels for each clause
- // before the main landing pad block.
- MachineInstrBuilder SelectorPHI = BuildMI(
- *MBB, MBB->begin(), SDB->getCurDebugLoc(), TII->get(TargetOpcode::PHI),
- FuncInfo->ExceptionSelectorVirtReg);
- for (unsigned I = 0, E = LPadInst->getNumClauses(); I != E; ++I) {
- // Skip filter clauses, we can't implement them yet.
- if (LPadInst->isFilter(I))
- continue;
-
- MachineBasicBlock *ClauseBB = MF->CreateMachineBasicBlock(LLVMBB);
- MF->insert(MBB, ClauseBB);
-
- // Add the edge from the invoke to the clause.
- for (MachineBasicBlock *InvokeBB : InvokeBBs)
- InvokeBB->addSuccessor(ClauseBB);
-
- // Mark the clause as a landing pad or MI passes will delete it.
- ClauseBB->setIsLandingPad();
-
- GlobalValue *ClauseGV = ExtractTypeInfo(LPadInst->getClause(I));
-
- // Start the BB with a label.
- MCSymbol *ClauseLabel = MF->getMMI().addClauseForLandingPad(MBB);
- BuildMI(*ClauseBB, ClauseBB->begin(), SDB->getCurDebugLoc(), II)
- .addSym(ClauseLabel);
-
- // Construct a simple BB that defines a register with the typeid constant.
- FuncInfo->MBB = ClauseBB;
- FuncInfo->InsertPt = ClauseBB->end();
- unsigned VReg = SDB->visitLandingPadClauseBB(ClauseGV, MBB);
- CurDAG->setRoot(SDB->getRoot());
- SDB->clear();
- CodeGenAndEmitDAG();
-
- // Add the typeid virtual register to the phi in the main landing pad.
- SelectorPHI.addReg(VReg).addMBB(ClauseBB);
- }
-
- // Remove the edge from the invoke to the lpad.
- for (MachineBasicBlock *InvokeBB : InvokeBBs)
- InvokeBB->removeSuccessor(MBB);
-
- // Restore FuncInfo back to its previous state and select the main landing
- // pad block.
- FuncInfo->MBB = MBB;
- FuncInfo->InsertPt = MBB->end();
- return;
- }
-