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
diff --git a/lib/CodeGen/TailDuplication.cpp b/lib/CodeGen/TailDuplication.cpp
index 5fe3cb0..93acd58 100644
--- a/lib/CodeGen/TailDuplication.cpp
+++ b/lib/CodeGen/TailDuplication.cpp
@@ -541,13 +541,13 @@
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 @@
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);