[llvm] [SelectionDAG][X86] Preserve unpredictable metadata for conditional branches in SelectionDAG, as well as JCCs generated by X86 backend. (PR #102101)

[Phoebe Wang via llvm-commits]

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@@ -137,29 +137,34 @@ struct CaseBlock {
   SDLoc DL;
   DebugLoc DbgLoc;
 
-  // Branch weights.
+  // Branch weights and predictability.
   BranchProbability TrueProb, FalseProb;
+  bool IsUnpredictable;
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phoebewang wrote:

Where this get used?

https://github.com/llvm/llvm-project/pull/102101