diff --git a/llvm/lib/CodeGen/BranchFolding.cpp b/llvm/lib/CodeGen/BranchFolding.cpp index 8093b29791e2..53cf0aabb9f9 100644 --- a/llvm/lib/CodeGen/BranchFolding.cpp +++ b/llvm/lib/CodeGen/BranchFolding.cpp @@ -675,6 +675,9 @@ bool BranchFolder::OptimizeBranches(MachineFunction &MF) { /// CFG to be inserted. If we have proven that MBB can only branch to DestA and /// DestB, remove any other MBB successors from the CFG. DestA and DestB can /// be null. +/// Besides DestA and DestB, retain other edges leading to LandingPads (currently +/// there can be only one; we don't check or require that here). +/// Note it is possible that DestA and/or DestB are LandingPads. static bool CorrectExtraCFGEdges(MachineBasicBlock &MBB, MachineBasicBlock *DestA, MachineBasicBlock *DestB, @@ -700,25 +703,19 @@ static bool CorrectExtraCFGEdges(MachineBasicBlock &MBB, } MachineBasicBlock::succ_iterator SI = MBB.succ_begin(); - bool foundPad = false; + MachineBasicBlock *OrigDestA = DestA, *OrigDestB = DestB; while (SI != MBB.succ_end()) { if (*SI == DestA && DestA == DestB) { DestA = DestB = 0; - if ((*SI)->isLandingPad()) - foundPad = true; ++SI; } else if (*SI == DestA) { DestA = 0; - if ((*SI)->isLandingPad()) - foundPad = true; ++SI; } else if (*SI == DestB) { DestB = 0; - if ((*SI)->isLandingPad()) - foundPad = true; ++SI; - } else if ((*SI)->isLandingPad() && !foundPad) { - foundPad = true; + } else if ((*SI)->isLandingPad() && + *SI!=OrigDestA && *SI!=OrigDestB) { ++SI; } else { // Otherwise, this is a superfluous edge, remove it.