[llvm] [NFC] Reduce copies created of ConstantRange when getting ConstantRangeAttributes. (PR #90335)

[Andreas Jonson via llvm-commits]

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@@ -2199,8 +2199,8 @@ class CallBase : public Instruction {
   FPClassTest getParamNoFPClass(unsigned i) const;
 
   /// If this return value has a range attribute, return the value range of the
-  /// argument. Otherwise, std::nullopt is returned.
-  std::optional<ConstantRange> getRange() const;
+  /// argument. Otherwise, nullptr is returned.
+  const ConstantRange *getRange() const;
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andjo403 wrote:

ok you was thinking that the intersection was done in the body of this function. But is it interesting to return the intersection shall not only the smallest of the ranges be returned feels like some thing is wrong if the the call do not contain the same range or a subrange of the declaration

https://github.com/llvm/llvm-project/pull/90335