[llvm] [SimplifyCFG] Handle that first matched eq cond in if chain can be Extra condition. (PR #154007)

[Yingwei Zheng via llvm-commits]

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@@ -581,8 +592,14 @@ struct ConstantComparesGatherer {
   /// Try to set the current value used for the comparison, it succeeds only if
   /// it wasn't set before or if the new value is the same as the old one
   bool setValueOnce(Value *NewVal) {
-    if (CompValue && CompValue != NewVal)
+    if (IgnoreFirstMatch && NewVal) {
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dtcxzyw wrote:

NewVal is non-null.

https://github.com/llvm/llvm-project/pull/154007