Teach SplitBlockPredecessors how to handle landingpad blocks.

Patch by: Igor Laevsky <igor@azulsystems.com>

"Currently SplitBlockPredecessors generates incorrect code in case if basic block we are going to split has a landingpad. Also seems like it is fairly common case among it's users to conditionally call either SplitBlockPredecessors or SplitLandingPadPredecessors. Because of this I think it is reasonable to add this condition directly into SplitBlockPredecessors."

Differential Revision: http://reviews.llvm.org/D7157

llvm-svn: 227390

1 files changed, 3 insertions, 10 deletions

diff --git a/llvm/lib/Transforms/Scalar/LoopUnswitch.cpp b/llvm/lib/Transforms/Scalar/LoopUnswitch.cpp
index 6bf8affcb2f..c78462f1d3f 100644
--- a/llvm/lib/Transforms/Scalar/LoopUnswitch.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopUnswitch.cpp
@@ -769,16 +769,9 @@ void LoopUnswitch::SplitExitEdges(Loop *L,
 
     // Although SplitBlockPredecessors doesn't preserve loop-simplify in
     // general, if we call it on all predecessors of all exits then it does.
-    if (!ExitBlock->isLandingPad()) {
-      SplitBlockPredecessors(ExitBlock, Preds, ".us-lcssa",
-                             /*AliasAnalysis*/ nullptr, DT, LI,
-                             /*PreserveLCSSA*/ true);
-    } else {
-      SmallVector<BasicBlock*, 2> NewBBs;
-      SplitLandingPadPredecessors(ExitBlock, Preds, ".us-lcssa", ".us-lcssa",
-                                  NewBBs, /*AliasAnalysis*/ nullptr, DT, LI,
-                                  /*PreserveLCSSA*/ true);
-    }
+    SplitBlockPredecessors(ExitBlock, Preds, ".us-lcssa",
+                           /*AliasAnalysis*/ nullptr, DT, LI,
+                           /*PreserveLCSSA*/ true);
   }
 }