[llvm] [IR] Add helper `CmpPredicate::dropSameSign` (PR #134071)

[Ramkumar Ramachandra via llvm-commits]

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@@ -41,6 +41,10 @@ class CmpPredicate {
   /// Query samesign information, for optimizations.
   bool hasSameSign() const { return HasSameSign; }
 
+  /// Drops samesign information. This is used when the samesign information
+  /// should be dropped explicitly.
+  CmpInst::Predicate withoutSameSign() const { return Pred; }
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artagnon wrote:

I don't think this is a problem in practice, as we already have things like SmallVector::drop_front().

https://github.com/llvm/llvm-project/pull/134071