<< FuncInfo->PHINodesToUpdate[i].first
<< ", " << FuncInfo->PHINodesToUpdate[i].second << ")\n");
+ const bool MustUpdatePHINodes = SDB->SwitchCases.empty() &&
+ SDB->JTCases.empty() &&
+ SDB->BitTestCases.empty();
+
// Next, now that we know what the last MBB the LLVM BB expanded is, update
// PHI nodes in successors.
- for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i) {
- MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[i].first);
- assert(PHI->isPHI() &&
- "This is not a machine PHI node that we are updating!");
- if (!FuncInfo->MBB->isSuccessor(PHI->getParent()))
- continue;
- PHI.addReg(FuncInfo->PHINodesToUpdate[i].second).addMBB(FuncInfo->MBB);
+ if (MustUpdatePHINodes) {
+ for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i) {
+ MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[i].first);
+ assert(PHI->isPHI() &&
+ "This is not a machine PHI node that we are updating!");
+ if (!FuncInfo->MBB->isSuccessor(PHI->getParent()))
+ continue;
+ PHI.addReg(FuncInfo->PHINodesToUpdate[i].second).addMBB(FuncInfo->MBB);
+ }
}
// Handle stack protector.
SDB->SPDescriptor.resetPerBBState();
}
+ // If we updated PHI Nodes, return early.
+ if (MustUpdatePHINodes)
+ return;
+
for (unsigned i = 0, e = SDB->BitTestCases.size(); i != e; ++i) {
// Lower header first, if it wasn't already lowered
if (!SDB->BitTestCases[i].Emitted) {
}
SDB->JTCases.clear();
+ // If the switch block involved a branch to one of the actual successors, we
+ // need to update PHI nodes in that block.
+ for (unsigned i = 0, e = FuncInfo->PHINodesToUpdate.size(); i != e; ++i) {
+ MachineInstrBuilder PHI(*MF, FuncInfo->PHINodesToUpdate[i].first);
+ assert(PHI->isPHI() &&
+ "This is not a machine PHI node that we are updating!");
+ if (FuncInfo->MBB->isSuccessor(PHI->getParent()))
+ PHI.addReg(FuncInfo->PHINodesToUpdate[i].second).addMBB(FuncInfo->MBB);
+ }
+
// If we generated any switch lowering information, build and codegen any
// additional DAGs necessary.
for (unsigned i = 0, e = SDB->SwitchCases.size(); i != e; ++i) {