Turns out AnalyzeBranch can modify the mbb being analyzed. This is a nasty
suprise to some callers, e.g. register coalescer. For now, add an parameter
that tells AnalyzeBranch whether it's safe to modify the mbb. A better
solution is out there, but I don't have time to deal with it right now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64124 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Mips/MipsInstrInfo.cpp b/lib/Target/Mips/MipsInstrInfo.cpp
index daff538..758e9be 100644
--- a/lib/Target/Mips/MipsInstrInfo.cpp
+++ b/lib/Target/Mips/MipsInstrInfo.cpp
@@ -453,7 +453,8 @@
bool MipsInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
- SmallVectorImpl<MachineOperand> &Cond) const
+ SmallVectorImpl<MachineOperand> &Cond,
+ bool AllowModify) const
{
// If the block has no terminators, it just falls into the block after it.
MachineBasicBlock::iterator I = MBB.end();
@@ -525,7 +526,8 @@
if ((SecondLastOpc == Mips::J) && (LastOpc == Mips::J)) {
TBB = SecondLastInst->getOperand(0).getMBB();
I = LastInst;
- I->eraseFromParent();
+ if (AllowModify)
+ I->eraseFromParent();
return false;
}