================
@@ -2018,9 +2018,42 @@ bool GVNPass::performLoopLoadPRE(LoadInst *Load,
   if (LoadPtr->canBeFreed())
     return false;
 
-  // TODO: Support critical edge splitting if blocker has more than 1 
successor.
+  // The reload is inserted at the end of the chosen in-loop block so its value
+  // reaches the header along the path back to the latch. If that block has
+  // multiple successors, inserting there would also run the load on paths that
+  // leave the loop. Split the critical edge to the unique in-loop successor so
+  // the reload only runs on the path that feeds the header.
+  BasicBlock *InsertBlock = LoopBlock;
+  if (LoopBlock->getTerminator()->getNumSuccessors() != 1) {
+    if (isa<IndirectBrInst>(LoopBlock->getTerminator()))
+      return false;
----------------
antoniofrighetto wrote:

Isn't this already checked in SplitKnownCriticalEdge()?

https://github.com/llvm/llvm-project/pull/206694
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