[llvm] [Local] Move OverflowTracking to Local.h, move logic to helpers (NFC) (PR #140403)

[Yingwei Zheng via llvm-commits]

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@@ -556,6 +556,27 @@ Value *invertCondition(Value *Condition);
 /// function, explicitly materialize the maximal set in the IR.
 bool inferAttributesFromOthers(Function &F);
 
+//===----------------------------------------------------------------------===//
+//  Helpers to track and update flags on instructions.
+//
+
+struct OverflowTracking {
+  bool HasNUW = true;
+  bool HasNSW = true;
+  bool AllKnownNonNegative = true;
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dtcxzyw wrote:

Please add a comment indicating that the user is responsible for updating `AllKnownNonNegative` and `AllKnownNonZero`.


https://github.com/llvm/llvm-project/pull/140403