Temporarily revert r134057: "Let simplify cfg simplify bb with only debug and
lifetime intrinsics" due to buildbot failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134071 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp
index 0046945..b1dd733 100644
--- a/lib/Transforms/Utils/Local.cpp
+++ b/lib/Transforms/Utils/Local.cpp
@@ -536,9 +536,9 @@
/// TryToSimplifyUncondBranchFromEmptyBlock - BB is known to contain an
/// unconditional branch, and contains no instructions other than PHI nodes,
-/// potential side-effect free intrinsics and the branch. If possible,
-/// eliminate BB by rewriting all the predecessors to branch to the successor
-/// block and return true. If we can't transform, return false.
+/// potential debug intrinsics and the branch. If possible, eliminate BB by
+/// rewriting all the predecessors to branch to the successor block and return
+/// true. If we can't transform, return false.
bool llvm::TryToSimplifyUncondBranchFromEmptyBlock(BasicBlock *BB) {
assert(BB != &BB->getParent()->getEntryBlock() &&
"TryToSimplifyUncondBranchFromEmptyBlock called on entry block!");
@@ -613,15 +613,13 @@
}
}
- if (Succ->getSinglePredecessor()) {
- // BB is the only predecessor of Succ, so Succ will end up with exactly
- // the same predecessors BB had.
-
- // Copy over any phi, debug or lifetime instruction.
- BB->getTerminator()->eraseFromParent();
- Succ->getInstList().splice(Succ->begin(), BB->getInstList());
- } else {
- while (PHINode *PN = dyn_cast<PHINode>(&BB->front())) {
+ while (PHINode *PN = dyn_cast<PHINode>(&BB->front())) {
+ if (Succ->getSinglePredecessor()) {
+ // BB is the only predecessor of Succ, so Succ will end up with exactly
+ // the same predecessors BB had.
+ Succ->getInstList().splice(Succ->begin(),
+ BB->getInstList(), BB->begin());
+ } else {
// We explicitly check for such uses in CanPropagatePredecessorsForPHIs.
assert(PN->use_empty() && "There shouldn't be any uses here!");
PN->eraseFromParent();