[RegionInfo] Remove unused and broken function splitBlock

Summary:
It always makes NewBB the entry of the region instead of OldBB. This breaks if there are edges from inside the region to OldBB. OldBB is moved out of the region and hence there are exiting edges to OldBB and the region's exit block, contradicting the single-exit condition for regions.

The only use from Polly is going to be removed, hence I propose to remove the function completely.

Reviewers: grosser

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11873

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@245092 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Analysis/RegionInfo.h b/include/llvm/Analysis/RegionInfo.h
index 8d1739a..4988386 100644 (file)
--- a/include/llvm/Analysis/RegionInfo.h
+++ b/include/llvm/Analysis/RegionInfo.h
@@ -800,12 +800,6 @@ public:
 
   RegionT *getTopLevelRegion() const { return TopLevelRegion; }
 
-  /// @brief Update RegionInfo after a basic block was split.
-  ///
-  /// @param NewBB The basic block that was created before OldBB.
-  /// @param OldBB The old basic block.
-  void splitBlock(BlockT *NewBB, BlockT *OldBB);
-
   /// @brief Clear the Node Cache for all Regions.
   ///
   /// @see Region::clearNodeCache()

diff --git a/include/llvm/Analysis/RegionInfoImpl.h b/include/llvm/Analysis/RegionInfoImpl.h
index a5157a9..0598068 100644 (file)
--- a/include/llvm/Analysis/RegionInfoImpl.h
+++ b/include/llvm/Analysis/RegionInfoImpl.h
@@ -911,20 +911,6 @@ RegionInfoBase<Tr>::getCommonRegion(SmallVectorImpl<BlockT *> &BBs) const {
 }
 
 template <class Tr>
-void RegionInfoBase<Tr>::splitBlock(BlockT *NewBB, BlockT *OldBB) {
-  RegionT *R = getRegionFor(OldBB);
-
-  setRegionFor(NewBB, R);
-
-  while (R->getEntry() == OldBB && !R->isTopLevelRegion()) {
-    R->replaceEntry(NewBB);
-    R = R->getParent();
-  }
-
-  setRegionFor(OldBB, R);
-}
-
-template <class Tr>
 void RegionInfoBase<Tr>::calculate(FuncT &F) {
   typedef typename std::add_pointer<FuncT>::type FuncPtrT;