[llvm] [BasicBlockUtils] Remove redundant llvm.dbg instructions after blocks to reduce compile time (PR #89069)

[Florian Hahn via llvm-commits]

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@@ -333,6 +333,10 @@ bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, DomTreeUpdater *DTU,
   // Finally, erase the old block and update dominator info.
   DeleteDeadBlock(BB, DTU);
 
+  // Remove redundant "llvm.dbg" instrunctions after blocks merged.
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fhahn wrote:

nit: after blocks have been merged

https://github.com/llvm/llvm-project/pull/89069