AnalyzeBranch modifies the bb, but we don't want to modify a bb with

eh edges. Swap the order of the checks to avoid it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132806 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Rafael Espindola 2011-06-09 21:43:25 +00:00
parent c2e9a50dfb
commit a899b22310

View File

@ -541,13 +541,13 @@ TailDuplicatePass::TailDuplicate(MachineBasicBlock *TailBB, MachineFunction &MF,
MachineBasicBlock *PredTBB, *PredFBB;
SmallVector<MachineOperand, 4> PredCond;
// EH edges are ignored by AnalyzeBranch.
if (PredBB->succ_size() != 1)
continue;
if (TII->AnalyzeBranch(*PredBB, PredTBB, PredFBB, PredCond, true))
continue;
if (!PredCond.empty())
continue;
// EH edges are ignored by AnalyzeBranch.
if (PredBB->succ_size() != 1)
continue;
// Don't duplicate into a fall-through predecessor (at least for now).
if (PredBB->isLayoutSuccessor(TailBB) && PredBB->canFallThrough())
continue;
@ -603,12 +603,11 @@ TailDuplicatePass::TailDuplicate(MachineBasicBlock *TailBB, MachineFunction &MF,
MachineBasicBlock *PrevBB = prior(MachineFunction::iterator(TailBB));
MachineBasicBlock *PriorTBB = 0, *PriorFBB = 0;
SmallVector<MachineOperand, 4> PriorCond;
bool PriorUnAnalyzable =
TII->AnalyzeBranch(*PrevBB, PriorTBB, PriorFBB, PriorCond, true);
// This has to check PrevBB->succ_size() because EH edges are ignored by
// AnalyzeBranch.
if (!PriorUnAnalyzable && PriorCond.empty() && !PriorTBB &&
TailBB->pred_size() == 1 && PrevBB->succ_size() == 1 &&
if (PrevBB->succ_size() == 1 &&
!TII->AnalyzeBranch(*PrevBB, PriorTBB, PriorFBB, PriorCond, true) &&
PriorCond.empty() && !PriorTBB && TailBB->pred_size() == 1 &&
!TailBB->hasAddressTaken()) {
DEBUG(dbgs() << "\nMerging into block: " << *PrevBB
<< "From MBB: " << *TailBB);