diff --git a/llvm/lib/CodeGen/MachineVerifier.cpp b/llvm/lib/CodeGen/MachineVerifier.cpp --- a/llvm/lib/CodeGen/MachineVerifier.cpp +++ b/llvm/lib/CodeGen/MachineVerifier.cpp @@ -81,6 +81,11 @@ using namespace llvm; +static cl::opt VerifierStrictLivein( + "machine-verifier-strict-livein", cl::Hidden, + cl::desc("Enable strict verification of basic block live-ins"), + cl::init(false)); + namespace { struct MachineVerifier { @@ -2434,19 +2439,36 @@ // that the register is in regsLiveOut of each predecessor block. Since // this must come from a definition in the predecesssor or its live-in // list, this will catch a live-through case where the predecessor does not - // have the register in its live-in list. This currently only checks - // registers that have no aliases, are not allocatable and are not - // reserved, which could mean a condition code register for instance. - if (MRI->tracksLiveness()) - for (const auto &MBB : *MF) + // have the register in its live-in list. + if (MRI->tracksLiveness()) { + for (const auto &MBB : *MF) { + if (MBB.isEHPad()) + continue; for (MachineBasicBlock::RegisterMaskPair P : MBB.liveins()) { MCPhysReg LiveInReg = P.PhysReg; + + // We don't track liveness for reserved registers. + if (isReserved(LiveInReg)) + continue; + + // Strict checking of allocatable/aliased registers is controlled by + // a flag to deal with regression test failures. bool hasAliases = MCRegAliasIterator(LiveInReg, TRI, false).isValid(); - if (hasAliases || isAllocatable(LiveInReg) || isReserved(LiveInReg)) + if (!VerifierStrictLivein && (hasAliases || isAllocatable(LiveInReg))) continue; + for (const MachineBasicBlock *Pred : MBB.predecessors()) { BBInfo &PInfo = MBBInfoMap[Pred]; - if (!PInfo.regsLiveOut.count(LiveInReg)) { + MCRegAliasIterator AliasingRegs(LiveInReg, TRI, true); + bool FoundPred = false; + while (AliasingRegs.isValid()) { + if (PInfo.regsLiveOut.count(*AliasingRegs)) { + FoundPred = true; + break; + } + ++AliasingRegs; + } + if (!FoundPred) { report("Live in register not found to be live out from predecessor.", &MBB); errs() << TRI->getName(LiveInReg) @@ -2455,6 +2477,8 @@ } } } + } + } for (auto CSInfo : MF->getCallSitesInfo()) if (!CSInfo.first->isCall())