Filter callbr insts from critical edge splitting

Similarly to how splitting predecessors with an indirectbr isn't handled
in the generic way, we also shouldn't split callbrs, for similar
reasons.

(cherry picked from commit 2fe457690da0fc38bc7f9f1d0aee2ba6a6a16ada)

2 files changed, 4 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Scalar/LICM.cpp b/llvm/lib/Transforms/Scalar/LICM.cpp
index 8c33045c238..eb023d49b0a 100644
--- a/llvm/lib/Transforms/Scalar/LICM.cpp
+++ b/llvm/lib/Transforms/Scalar/LICM.cpp
@@ -1537,7 +1537,8 @@ static bool canSplitPredecessors(PHINode *PN, LoopSafetyInfo *SafetyInfo) {
     return false;
   for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
     BasicBlock *BBPred = *PI;
-    if (isa<IndirectBrInst>(BBPred->getTerminator()))
+    if (isa<IndirectBrInst>(BBPred->getTerminator()) ||
+        isa<CallBrInst>(BBPred->getTerminator()))
       return false;
   }
   return true;
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index c9eb4abfa21..9a7379e27ed 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -505,7 +505,8 @@ llvm::SplitAllCriticalEdges(Function &F,
   unsigned NumBroken = 0;
   for (BasicBlock &BB : F) {
     Instruction *TI = BB.getTerminator();
-    if (TI->getNumSuccessors() > 1 && !isa<IndirectBrInst>(TI))
+    if (TI->getNumSuccessors() > 1 && !isa<IndirectBrInst>(TI) &&
+        !isa<CallBrInst>(TI))
       for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
         if (SplitCriticalEdge(TI, i, Options))
           ++NumBroken;