diff --git a/lib/CodeGen/PHIElimination.cpp b/lib/CodeGen/PHIElimination.cpp index b3802ed6725..53ab8b03ee7 100644 --- a/lib/CodeGen/PHIElimination.cpp +++ b/lib/CodeGen/PHIElimination.cpp @@ -439,21 +439,21 @@ MachineBasicBlock *PHIElimination::SplitCriticalEdge(MachineBasicBlock *A, ++NumSplits; MachineBasicBlock *NMBB = MF->CreateMachineBasicBlock(); - MF->push_back(NMBB); + MF->insert(next(MachineFunction::iterator(A)), NMBB); DEBUG(errs() << "PHIElimination splitting critical edge:" " BB#" << A->getNumber() << " -- BB#" << NMBB->getNumber() << " -- BB#" << B->getNumber() << '\n'); A->ReplaceUsesOfBlockWith(B, NMBB); - // If A may fall through to B, we may have to insert a branch. - if (A->isLayoutSuccessor(B)) - A->updateTerminator(); + A->updateTerminator(); - // Insert unconditional "jump B" instruction in NMBB. + // Insert unconditional "jump B" instruction in NMBB if necessary. NMBB->addSuccessor(B); - Cond.clear(); - MF->getTarget().getInstrInfo()->InsertBranch(*NMBB, B, NULL, Cond); + if (!NMBB->isLayoutSuccessor(B)) { + Cond.clear(); + MF->getTarget().getInstrInfo()->InsertBranch(*NMBB, B, NULL, Cond); + } // Fix PHI nodes in B so they refer to NMBB instead of A for (MachineBasicBlock::iterator i = B->begin(), e = B->end();