Revert commit 142891. Takumi bisected the tablegen miscompiles
down to this commit. Original commit message:
An MBB which branches to an EH landing pad shouldn't be considered for tail merging.
In SjLj EH, the jump to the landing pad is not done explicitly through a branch
statement. The EH landing pad is added as a successor to the throwing
BB. Because of that however, the branch folding pass could mistakenly think that
it could merge the throwing BB with another BB. This isn't safe to do.
<rdar://problem/10334833>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142920 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/BranchFolding.cpp b/lib/CodeGen/BranchFolding.cpp
index 2c39f64..75288b0 100644
--- a/lib/CodeGen/BranchFolding.cpp
+++ b/lib/CodeGen/BranchFolding.cpp
@@ -913,8 +913,7 @@
// reinsert conditional branch only, for now
TII->InsertBranch(*PBB, (TBB == IBB) ? FBB : TBB, 0, NewCond, dl);
}
- if (!PBB->getLandingPadSuccessor())
- MergePotentials.push_back(MergePotentialsElt(HashEndOfMBB(PBB),*P));
+ MergePotentials.push_back(MergePotentialsElt(HashEndOfMBB(PBB), *P));
}
}
// If this is a large problem, avoid visiting the same basic blocks