Revert "Ensure SplitEdge to return the new block between the two given blocks"

This reverts commit cf638d793c489632bbcf0ee0fbf9d0f8c76e1f48.

1 files changed, 2 insertions, 50 deletions

diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 14795d4..85d1be1 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -510,7 +510,7 @@ BasicBlock *llvm::SplitEdge(BasicBlock *BB, BasicBlock *Succ, DominatorTree *DT,
     // block.
     assert(SP == BB && "CFG broken");
     SP = nullptr;
-    return SplitBlock(Succ, &Succ->front(), DT, LI, MSSAU, "", /*Before=*/true);
+    return SplitBlock(Succ, &Succ->front(), DT, LI, MSSAU);
   }
 
   // Otherwise, if BB has a single successor, split it at the bottom of the
@@ -537,10 +537,7 @@ llvm::SplitAllCriticalEdges(Function &F,
 
 BasicBlock *llvm::SplitBlock(BasicBlock *Old, Instruction *SplitPt,
                              DominatorTree *DT, LoopInfo *LI,
-                             MemorySSAUpdater *MSSAU, const Twine &BBName,
-                             bool Before) {
-  if (Before)
-    return splitBlockBefore(Old, SplitPt, DT, LI, MSSAU, BBName);
+                             MemorySSAUpdater *MSSAU, const Twine &BBName) {
   BasicBlock::iterator SplitIt = SplitPt->getIterator();
   while (isa<PHINode>(SplitIt) || SplitIt->isEHPad())
     ++SplitIt;
@@ -572,51 +569,6 @@ BasicBlock *llvm::SplitBlock(BasicBlock *Old, Instruction *SplitPt,
   return New;
 }
 
-BasicBlock *llvm::splitBlockBefore(BasicBlock *Old, Instruction *SplitPt,
-                                   DominatorTree *DT, LoopInfo *LI,
-                                   MemorySSAUpdater *MSSAU,
-                                   const Twine &BBName) {
-
-  BasicBlock::iterator SplitIt = SplitPt->getIterator();
-  while (isa<PHINode>(SplitIt) || SplitIt->isEHPad())
-    ++SplitIt;
-  std::string Name = BBName.str();
-  BasicBlock *New = Old->splitBasicBlock(
-      SplitIt, Name.empty() ? Old->getName() + ".split" : Name,
-      /* Before=*/true);
-
-  // The new block lives in whichever loop the old one did. This preserves
-  // LCSSA as well, because we force the split point to be after any PHI nodes.
-  if (LI)
-    if (Loop *L = LI->getLoopFor(Old))
-      L->addBasicBlockToLoop(New, *LI);
-
-  if (DT) {
-    DomTreeUpdater DTU(DT, DomTreeUpdater::UpdateStrategy::Lazy);
-    SmallVector<DominatorTree::UpdateType, 8> DTUpdates;
-    // New dominates Old. The predecessor nodes of the Old node dominate
-    // New node.
-    DTUpdates.push_back({DominatorTree::Insert, New, Old});
-    for (BasicBlock *Pred : predecessors(New))
-      if (DT->getNode(Pred)) {
-        DTUpdates.push_back({DominatorTree::Insert, Pred, New});
-        DTUpdates.push_back({DominatorTree::Delete, Pred, Old});
-      }
-
-    DTU.applyUpdates(DTUpdates);
-    DTU.flush();
-
-    // Move MemoryAccesses still tracked in Old, but part of New now.
-    // Update accesses in successor blocks accordingly.
-    if (MSSAU) {
-      MSSAU->applyUpdates(DTUpdates, *DT);
-      if (VerifyMemorySSA)
-        MSSAU->getMemorySSA()->verifyMemorySSA();
-    }
-  }
-  return New;
-}
-
 /// Update DominatorTree, LoopInfo, and LCCSA analysis information.
 static void UpdateAnalysisInformation(BasicBlock *OldBB, BasicBlock *NewBB,
                                       ArrayRef<BasicBlock *> Preds,